Sample records for accelerated hypofractionated radiotherapy

  1. High-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine and carboplatin chemotherapy in locally advanced non-small-cell lung cancer: a feasibility study.

    PubMed

    Liu, Yue-E; Lin, Qiang; Meng, Fan-Jie; Chen, Xue-Ji; Ren, Xiao-Cang; Cao, Bin; Wang, Na; Zong, Jie; Peng, Yu; Ku, Ya-Jun; Chen, Yan

    2013-08-11

    Increasing the radiotherapy dose can result in improved local control for non-small-cell lung cancer (NSCLC) and can thereby improve survival. Accelerated hypofractionated radiotherapy can expose tumors to a high dose of radiation in a short period of time, but the optimal treatment regimen remains unclear. The purpose of this study was to evaluate the feasibility of utilizing high-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine (NVB) and carboplatin (CBP) chemotherapy for the treatment of local advanced NSCLC. Untreated patients with unresectable stage IIIA/IIIB NSCLC or patients with a recurrence of NSCLC received accelerated hypofractionated three-dimensional conformal radiotherapy. The total dose was greater than or equal to 60 Gy. The accelerated hypofractionated radiotherapy was conducted once daily at 3 Gy/fraction with 5 fractions per week, and the radiotherapy was completed in 5 weeks. In addition to radiotherapy, the patients also received at least 1 cycle of a concurrent two-drug chemotherapy regimen of NVB and CBP. A total of 26 patients (19 previously untreated cases and 7 cases of recurrent disease) received 60Gy-75Gy radiotherapy with concurrent chemotherapy. All of the patients underwent evaluations for toxicity and preliminary therapeutic efficacy. There were no treatment-related deaths within the entire patient group. The major acute adverse reactions were radiation esophagitis (88.5%) and radiation pneumonitis (42.3%). The percentages of grade III acute radiation esophagitis and grade III radiation pneumonitis were 15.4% and 7.7%, respectively. Hematological toxicities were common and did not significantly affect the implementation of chemoradiotherapy after supportive treatment. Two patients received high dose of 75 Gy had grade III late esophageal toxicity, and none had grade IV and above. Grade III and above late lung toxicity did not occur. High-dose accelerated

  2. High-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine and carboplatin chemotherapy in locally advanced non-small-cell lung cancer: a feasibility study

    PubMed Central

    2013-01-01

    Background Increasing the radiotherapy dose can result in improved local control for non-small-cell lung cancer (NSCLC) and can thereby improve survival. Accelerated hypofractionated radiotherapy can expose tumors to a high dose of radiation in a short period of time, but the optimal treatment regimen remains unclear. The purpose of this study was to evaluate the feasibility of utilizing high-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine (NVB) and carboplatin (CBP) chemotherapy for the treatment of local advanced NSCLC. Methods Untreated patients with unresectable stage IIIA/IIIB NSCLC or patients with a recurrence of NSCLC received accelerated hypofractionated three-dimensional conformal radiotherapy. The total dose was greater than or equal to 60 Gy. The accelerated hypofractionated radiotherapy was conducted once daily at 3 Gy/fraction with 5 fractions per week, and the radiotherapy was completed in 5 weeks. In addition to radiotherapy, the patients also received at least 1 cycle of a concurrent two-drug chemotherapy regimen of NVB and CBP. Results A total of 26 patients (19 previously untreated cases and 7 cases of recurrent disease) received 60Gy-75Gy radiotherapy with concurrent chemotherapy. All of the patients underwent evaluations for toxicity and preliminary therapeutic efficacy. There were no treatment-related deaths within the entire patient group. The major acute adverse reactions were radiation esophagitis (88.5%) and radiation pneumonitis (42.3%). The percentages of grade III acute radiation esophagitis and grade III radiation pneumonitis were 15.4% and 7.7%, respectively. Hematological toxicities were common and did not significantly affect the implementation of chemoradiotherapy after supportive treatment. Two patients received high dose of 75 Gy had grade III late esophageal toxicity, and none had grade IV and above. Grade III and above late lung toxicity did not occur

  3. Management of Mediastinal Relapse after Treatment with Stereotactic Body Radiotherapy or Accelerated Hypofractionated Radiotherapy for Stage I/II Non–Small-Cell Lung Cancer

    PubMed Central

    Kilburn, Jeremy M.; Lester, Scott C.; Lucas, John T.; Soike, Michael H.; Blackstock, A. William; Kearns, William T.; Hinson, William H.; Miller, Antonius A.; Petty, William J.; Munley, Michael T.; Urbanic, James J.

    2014-01-01

    Purpose/Objective(s) Regional failures occur in up to 15% of patients treated with stereotactic body radiotherapy (SBRT) for stage I/II lung cancer. This report focuses on the management of the unique scenario of isolated regional failures. Methods Patients treated initially with SBRT or accelerated hypo-fractionated radiotherapy were screened for curative intent treatment of isolated mediastinal failures (IMFs). Local control, regional control, progression-free survival, and distant control were estimated from the date of salvage treatment using the Kaplan–Meier method. Results Among 160 patients treated from 2002 to 2012, 12 suffered IMF and were amenable to salvage treatment. The median interval between treatments was 16 months (2–57 mo). Median salvage dose was 66 Gy (60–70 Gy). With a median follow-up of 10 months, the median overall survival was 15 months (95% confidence interval, 5.8–37 mo). When estimated from original treatment, the median overall survival was 38 months (95% confidence interval, 17–71 mo). No subsequent regional failures occurred. Distant failure was the predominant mode of relapse following salvage for IMF with a 2-year distant control rate of 38%. At the time of this analysis, three patients have died without recurrence while four are alive and no evidence of disease. High-grade toxicity was uncommon. Conclusions To our knowledge, this is first analysis of salvage mediastinal radiation after SBRT or accelerated hypofractionated radiotherapy in lung cancer. Outcomes appear similar to stage III disease at presentation. Distant failures were common, suggesting a role for concurrent or sequential chemotherapy. A standard full course of external beam radiotherapy is advisable in this unique clinical scenario. PMID:24736084

  4. Dose-per-fraction escalation of accelerated hypofractionated three-dimensional conformal radiotherapy in locally advanced non-small cell lung cancer.

    PubMed

    Kepka, Lucyna; Tyc-Szczepaniak, Dobromira; Bujko, Krzysztof

    2009-07-01

    To determine the efficacy of accelerated hypofractionated three-dimensional conformal radiotherapy (3D-CRT) with dose-per-fraction escalation for treatment of stage III non-small cell lung cancer (NSCLC). Between 2001 and 2007, 173 patients with stage III NSCLC were treated using accelerated 3D-CRT and the simultaneous boost technique. Initially, the total dose of 56.7 Gy (including 39.9 Gy to the elective area) was delivered over 4 weeks in fractions of 2.7 Gy (1.9 Gy to the elective area). The dose-per-fraction escalation study commenced after the outcomes of 70 patients had been evaluated. The dose per fraction was increased from 2.7 through 2.8 Gy (level 1 escalation) to 2.9 Gy (level 2 escalation); the total dose increased, respectively, from 56.7 Gy through 58.8 Gy to 60.9 Gy. The dose to the elective area and the overall treatment time remained unchanged. Fit patients received two to three courses of chemotherapy before radiotherapy. The 2- and 3-year overall survival rates were 32 and 19%, respectively (median survival = 17 months). Of the patients, 7% had grade III acute esophageal toxicity and 6% had grade III or greater late pulmonary toxicity. Two of the nine patients who received the level 2 escalation (60.9 Gy) died of pulmonary toxicity. The study was terminated at a dose of 58.8 Gy and this schema was adopted as the institutional policy for treatment of stage III NSCLC. Although dose escalation with accelerated hypofractionated 3D-CRT was limited, the results and toxicity profiles obtained using this technique are promising.

  5. Stereotactic Radiosurgery and Hypofractionated Radiotherapy for Glioblastoma.

    PubMed

    Shah, Jennifer L; Li, Gordon; Shaffer, Jenny L; Azoulay, Melissa I; Gibbs, Iris C; Nagpal, Seema; Soltys, Scott G

    2018-01-01

    Glioblastoma is the most common primary brain tumor in adults. Standard therapy depends on patient age and performance status but principally involves surgical resection followed by a 6-wk course of radiation therapy given concurrently with temozolomide chemotherapy. Despite such treatment, prognosis remains poor, with a median survival of 16 mo. Challenges in achieving local control, maintaining quality of life, and limiting toxicity plague treatment strategies for this disease. Radiotherapy dose intensification through hypofractionation and stereotactic radiosurgery is a promising strategy that has been explored to meet these challenges. We review the use of hypofractionated radiotherapy and stereotactic radiosurgery for patients with newly diagnosed and recurrent glioblastoma. Copyright © 2017 by the Congress of Neurological Surgeons.

  6. High dose hypofractionated frameless volumetric modulated arc radiotherapy is a feasible method for treating canine trigeminal nerve sheath tumors.

    PubMed

    Dolera, Mario; Malfassi, Luca; Marcarini, Silvia; Mazza, Giovanni; Carrara, Nancy; Pavesi, Simone; Sala, Massimo; Finesso, Sara; Urso, Gaetano

    2018-06-08

    The aim of this prospective pilot study was to evaluate the feasibility and effectiveness of curative intent high dose hypofractionated frameless volumetric modulated arc radiotherapy for treatment of canine trigeminal peripheral nerve sheath tumors. Client-owned dogs with a presumptive imaging-based diagnosis of trigeminal peripheral nerve sheath tumor were recruited for the study during the period of February 2010 to December 2013. Seven dogs were enrolled and treated with high dose hypofractionated volumetric modulated arc radiotherapy delivered by a 6 MV linear accelerator equipped with a micro-multileaf beam collimator. The plans were computed using a Monte Carlo algorithm with a prescription dose of 37 Gy delivered in five fractions on alternate days. Overall survival was estimated using a Kaplan-Meier curve analysis. Magnetic resonance imaging (MRI) follow-up examinations revealed complete response in one dog, partial response in four dogs, and stable disease in two dogs. Median overall survival was 952 days with a 95% confidence interval of 543-1361 days. Volumetric modulated arc radiotherapy was demonstrated to be feasible and effective for trigeminal peripheral nerve sheath tumor treatment in this sample of dogs. The technique required few sedations and spared organs at risk. Even though larger studies are required, these preliminary results supported the use of high dose hypofractionated volumetric modulated arc radiotherapy as an alternative to other treatment modalities. © 2018 American College of Veterinary Radiology.

  7. [Hypofractionation and radiotherapy: "the eternal return"].

    PubMed

    Cosset, J-M; Mornex, F; Eschwège, F

    2013-10-01

    Hypofractionation is not a new idea in radiotherapy. The use of a few high-dose fractions has been proposed by some pioneers of our specialty in the early years of the 20th century. Hypofractionation then reappeared several times in the next decades, based on successive radiobiological concepts, a number of them having been shown to be wrong. The nominal single dose (NSD), for example, so fashionable in the 1970's, dramatically underestimated the late toxicity of the high-dose fractions. Consequently, the NSD was directly responsible for a significant increase of the incidence and of the severity of late complications in large cohorts of patients. The linear-quadratic model (LQ) unequivocally improved our understanding of fractionation sensitivity, but one has to keep in mind its limitations, both in the areas of low and high doses per fraction. For more than a decade, prostate cancer has been the subject of fierce discussions about its sensitivity to fractionation. A number of studies have suggested an unusually low (for a malignant tumor) alpha/beta ratio. However, the available data do not allow a precise evaluation of this ratio; "very low" (1.5 Gy), with an advantage of hypofractionation in terms of local control? Or simply "low" (3-4 Gy), only allowing a reduction of the total number of fractions (with a dose adequately reduced)? While waiting for complementary data, it is advised to remain very careful when modifying the classical schemes towards hypofractionation. Copyright © 2013. Published by Elsevier SAS.

  8. Dose constraints for moderate hypofractionated radiotherapy for prostate cancer: The French genito-urinary group (GETUG) recommendations.

    PubMed

    Langrand-Escure, J; de Crevoisier, R; Llagostera, C; Créhange, G; Delaroche, G; Lafond, C; Bonin, C; Bideault, F; Sargos, P; Belhomme, S; Pasquier, D; Latorzeff, I; Supiot, S; Hennequin, C

    2018-04-01

    Considering recent phase III trials results, moderate hypofractionated radiotherapy can be considered as a standard treatment for low and intermediate risk prostate cancer management. This assessment call for a framework allowing homogeneous and reproducible practices in the different centers using this radiotherapy schedule. The French Genito-Urinary Group (GETUG) provides here recommendations for daily practice of moderate hypofractionated radiotherapy for prostate cancer, with indications, dose, fractionation, pre-treatment planning, volume of interest delineation (target volume and organs at risk) and margins, dose constraints and radiotherapy techniques. Copyright © 2018. Published by Elsevier SAS.

  9. Efficacy of hypofractionated radiotherapy for nasal tumours in 38 dogs (2005-2008).

    PubMed

    Fujiwara, A; Kobayashi, T; Kazato, Y; Yayoshi, N; Fujita, M

    2013-02-01

    To evaluate the efficacy of hypofractionated radiotherapy for canine nasal tumours, including the improvement in clinical signs, rate of complications and assessment of prognostic factors. Medical records of 38 dogs with malignant nasal tumours were reviewed, and those treated with a weekly schedule of hypofractionated radiotherapy were included in the study. Acute and late side effects were defined as complications noted either within 1 month or after 6 months of irradiation, respectively. Progression-free interval and overall survival were calculated using the Kaplan-Meier method. Log-rank test and Cox proportional hazard model were also performed. Clinical signs improved in 30 of 36 dogs. Acute complications were seen in 28 of 36 dogs and were considered manageable. Late complications were observed in 17 of 30 dogs that survived 6 months or longer, but severe side effects were not observed. The median progression-free interval and overall survival was 245 days (95% CI: 127-512 days) and 512 days (95% CI: 203-820 days), respectively. Age, breed and presence of dyspnoea were negatively correlated with overall survival. These results suggest that hypofractionated radiotherapy could be a viable option for the treatment of nasal tumours in dogs that are not candidates for conventional multi-fractionated radiotherapy. © 2013 British Small Animal Veterinary Association.

  10. Radiobiology of hypofractionated stereotactic radiotherapy: what are the optimal fractionation schedules?

    PubMed Central

    Shibamoto, Yuta; Miyakawa, Akifumi; Otsuka, Shinya; Iwata, Hiromitsu

    2016-01-01

    In hypofractionated stereotactic radiotherapy (SRT), high doses per fraction are usually used and the dose delivery pattern is different from that of conventional radiation. The daily dose is usually given intermittently over a longer time compared with conventional radiotherapy. During prolonged radiation delivery, sublethal damage repair takes place, leading to the decreased effect of radiation. In in vivo tumors, however, this decrease in effect may be counterbalanced by rapid reoxygenation. Another issue related to hypofractionated SRT is the mathematical model for dose evaluation and conversion. The linear–quadratic (LQ) model and biologically effective dose (BED) have been suggested to be incorrect when used for hypofractionation. The LQ model overestimates the effect of high fractional doses of radiation. BED is particularly incorrect when used for tumor responses in vivo, since it does not take reoxygenation into account. Correction of the errors, estimated at 5–20%, associated with the use of BED is necessary when it is used for SRT. High fractional doses have been reported to exhibit effects against tumor vasculature and enhance host immunity, leading to increased antitumor effects. This may be an interesting topic that should be further investigated. Radioresistance of hypoxic tumor cells is more problematic in hypofractionated SRT, so trials of hypoxia-targeted agents are encouraged in the future. In this review, the radiobiological characteristics of hypofractionated SRT are summarized, and based on the considerations, we would like to recommend 60 Gy in eight fractions delivered three times a week for lung tumors larger than 2 cm in diameter. PMID:27006380

  11. Phase II Study to Assess the Efficacy of Hypofractionated Stereotactic Radiotherapy in Patients With Large Cavernous Sinus Hemangiomas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang Xin; Liu Xiaoxia; Mei Guanghai

    Purpose: Cavernous sinus hemangioma is a rare vascular tumor. The direct microsurgical approach usually results in massive hemorrhage. Although radiosurgery plays an important role in managing cavernous sinus hemangiomas as a treatment alternative to microsurgery, the potential for increased toxicity with single-session treatment of large tumors is a concern. The purpose of this study was to assess the efficacy of hypofractionated stereotactic radiotherapy in patients with large cavernous sinus hemangiomas. Methods: Fourteen patients with large (volume >20 cm{sup 3}) cavernous sinus hemangiomas were enrolled in a prospective Phase II study between December 2007 and December 2010. The hypofractionated stereotactic radiotherapymore » dose was 21 Gy delivered in 3 fractions. Results: After a mean follow-up of 15 months (range, 6-36 months), the magnetic resonance images showed a mean of 77% tumor volume reduction (range, 44-99%). Among the 6 patients with cranial nerve impairments before hypofractionated stereotactic radiotherapy, 1 achieved symptomatic complete resolution and 5 had improvement. No radiotherapy-related complications were observed during follow-up. Conclusion: Our current experience, though preliminary, substantiates the role of hypofractionated stereotactic radiotherapy for large cavernous sinus hemangiomas. Although a longer and more extensive follow-up is needed, hypofractionated stereotactic radiotherapy of 21 Gy delivered in 3 fractions is effective in reducing the tumor volume without causing any new deficits and can be considered as a treatment modality for large cavernous sinus hemangiomas.« less

  12. Effect of image-guided hypofractionated stereotactic radiotherapy on peripheral non-small-cell lung cancer

    PubMed Central

    Wang, Shu-wen; Ren, Juan; Yan, Yan-li; Xue, Chao-fan; Tan, Li; Ma, Xiao-wei

    2016-01-01

    The objective of this study was to compare the effects of image-guided hypofractionated radiotherapy and conventional fractionated radiotherapy on non-small-cell lung cancer (NSCLC). Fifty stage- and age-matched cases with NSCLC were randomly divided into two groups (A and B). There were 23 cases in group A and 27 cases in group B. Image-guided radiotherapy (IGRT) and stereotactic radiotherapy were conjugately applied to the patients in group A. Group A patients underwent hypofractionated radiotherapy (6–8 Gy/time) three times per week, with a total dose of 64–66 Gy; group B received conventional fractionated radiotherapy, with a total dose of 68–70 Gy five times per week. In group A, 1-year and 2-year local failure survival rate and 1-year local failure-free survival rate were significantly higher than in group B (P<0.05). The local failure rate (P<0.05) and distant metastasis rate (P>0.05) were lower in group A than in group B. The overall survival rate of group A was significantly higher than that of group B (P=0.03), and the survival rate at 1 year was 87% vs 63%, (P<0.05). The median survival time of group A was longer than that of group B. There was no significant difference in the incidence of complications between the two groups (P>0.05). Compared with conventional fractionated radiation therapy, image-guided hypofractionated stereotactic radiotherapy in NSCLC received better treatment efficacy and showed good tolerability. PMID:27574441

  13. Accelerated hypofractionated three-dimensional conformal radiation therapy (3 Gy/fraction) combined with concurrent chemotherapy for patients with unresectable stage III non-small cell lung cancer: preliminary results of an early terminated phase II trial.

    PubMed

    Ren, Xiao-Cang; Wang, Quan-Yu; Zhang, Rui; Chen, Xue-Ji; Wang, Na; Liu, Yue-E; Zong, Jie; Guo, Zhi-Jun; Wang, Dong-Ying; Lin, Qiang

    2016-04-23

    Increasing the biological effective dose (BED) of radiotherapy for non-small cell lung cancer (NSCLC) can increase local control rates and improve overall survival. Compared with conventional fractionated radiotherapy, accelerated hypofractionated radiotherapy can yield higher BED, shorten the total treatment time, and theoretically obtain better efficacy. However, currently, there is no optimal hypofractionated radiotherapy regimen. Based on phase I trial results, we performed this phase II trial to further evaluate the safety and preliminary efficacy of accelerated hypofractionated three-dimensional conformal radiation therapy(3-DCRT) combined with concurrent chemotherapy for patients with unresectable stage III NSCLC. Patients with previously untreated unresectable stage III NSCLC received 3-DCRT with a total dose of 69 Gy, delivered at 3 Gy per fraction, once daily, five fractions per week, completed within 4.6 weeks. At the same time, platinum doublet chemotherapy was applied. After 12 patients were enrolled in the group, the trial was terminated early. There were five cases of grade III radiation esophagitis, of which four cases completed the radiation doses of 51 Gy, 51 Gy, 54 Gy, and 66 Gy, and one case had 16 days of radiation interruption. The incidence of grade III acute esophagitis in patients receiving an irradiation dose per fraction ≥2.7 Gy on the esophagus was 83.3% (5/6). The incidence of symptomatic grade III radiation pneumonitis among the seven patients who completed 69 Gy according to the plan was 28.6% (2/7). The median local control (LC) and overall survival (OS) were not achieved; the 1-year LC rate was 59.3%, and the 1-year OS rate was 78.6%. For unresectable stage III NSCLC, the accelerated hypofractionated radiotherapy with a total dose of 69 Gy (3 Gy/f) combined with concurrent chemotherapy might result in severe radiation esophagitis and pneumonitis to severely affect the completion of the radiotherapy. Therefore, we considered that

  14. Early hypofractionated salvage radiotherapy for postprostatectomy biochemical recurrence.

    PubMed

    Kruser, Tim J; Jarrard, David F; Graf, Andrew K; Hedican, Sean P; Paolone, David R; Wegenke, John D; Liu, Glenn; Geye, Heather M; Ritter, Mark A

    2011-06-15

    Postprostatectomy adjuvant or salvage radiotherapy, when using standard fractionation, requires 6.5 to 8 weeks of treatment. The authors report on the safety and efficacy of an expedited radiotherapy course for salvage prostate radiotherapy. A total of 108 consecutive patients were treated with salvage radiation therapy to 65 grays (Gy) in 26 fractions of 2.5 Gy. Median follow-up was 32.4 months. Median presalvage prostate-specific antigen (PSA) was 0.44 (range, 0.05-9.50). Eighteen (17%) patients received androgen deprivation after surgery or concurrently with radiation. The actuarial freedom from biochemical failure for the entire group at 4 years was 67% ± 5.3%. An identical 67% control rate was seen at 5 years for the first 50 enrolled patients, whose median follow-up was longer at 43 months. One acute grade 3 genitourinary toxicity occurred, with no acute grade 3 gastrointestinal and no late grade 3 toxicities observed. On univariate analysis, higher Gleason score (P = .006), PSA doubling time ≤12 months (P = .03), perineural invasion (P = .06), and negative margins (P = .06) showed association with unsuccessful salvage. On multivariate analysis, higher Gleason score (P = .057) and negative margins (P = .088) retained an association with biochemical failure. Hypofractionated radiotherapy (65 Gy in 2.5 Gy fractions in about 5 weeks) reduces the length of treatment by from 1-½ to 3 weeks relative to other treatment schedules commonly used, produces low rates of toxicity, and demonstrates encouraging efficacy at 4 to 5 years. Hypofractionation may provide a convenient, resource-efficient, and well-tolerated salvage approach for the estimated 20,000 to 35,000 US men per year experiencing biochemical recurrence after prostatectomy. Copyright © 2010 American Cancer Society.

  15. A feasibility study of treatment verification using EPID cine images for hypofractionated lung radiotherapy

    NASA Astrophysics Data System (ADS)

    Tang, Xiaoli; Lin, Tong; Jiang, Steve

    2009-09-01

    We propose a novel approach for potential online treatment verification using cine EPID (electronic portal imaging device) images for hypofractionated lung radiotherapy based on a machine learning algorithm. Hypofractionated radiotherapy requires high precision. It is essential to effectively monitor the target to ensure that the tumor is within the beam aperture. We modeled the treatment verification problem as a two-class classification problem and applied an artificial neural network (ANN) to classify the cine EPID images acquired during the treatment into corresponding classes—with the tumor inside or outside of the beam aperture. Training samples were generated for the ANN using digitally reconstructed radiographs (DRRs) with artificially added shifts in the tumor location—to simulate cine EPID images with different tumor locations. Principal component analysis (PCA) was used to reduce the dimensionality of the training samples and cine EPID images acquired during the treatment. The proposed treatment verification algorithm was tested on five hypofractionated lung patients in a retrospective fashion. On average, our proposed algorithm achieved a 98.0% classification accuracy, a 97.6% recall rate and a 99.7% precision rate. This work was first presented at the Seventh International Conference on Machine Learning and Applications, San Diego, CA, USA, 11-13 December 2008.

  16. Tumor Control Outcomes After Hypofractionated and Single-Dose Stereotactic Image-Guided Intensity-Modulated Radiotherapy for Extracranial Metastases From Renal Cell Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zelefsky, Michael J., E-mail: zelefskm@mskcc.org; Greco, Carlo; Motzer, Robert

    2012-04-01

    Purpose: To report tumor local progression-free outcomes after treatment with single-dose, image-guided, intensity-modulated radiotherapy and hypofractionated regimens for extracranial metastases from renal cell primary tumors. Patients and Methods: Between 2004 and 2010, 105 lesions from renal cell carcinoma were treated with either single-dose, image-guided, intensity-modulated radiotherapy to a prescription dose of 18-24 Gy (median, 24) or hypofractionation (three or five fractions) with a prescription dose of 20-30 Gy. The median follow-up was 12 months (range, 1-48). Results: The overall 3-year actuarial local progression-free survival for all lesions was 44%. The 3-year local progression-free survival for those who received a highmore » single-dose (24 Gy; n = 45), a low single-dose (<24 Gy; n = 14), or hypofractionation regimens (n = 46) was 88%, 21%, and 17%, respectively (high single dose vs. low single dose, p = .001; high single dose vs. hypofractionation, p < .001). Multivariate analysis revealed the following variables were significant predictors of improved local progression-free survival: 24 Gy dose compared with a lower dose (p = .009) and a single dose vs. hypofractionation (p = .008). Conclusion: High single-dose, image-guided, intensity-modulated radiotherapy is a noninvasive procedure resulting in high probability of local tumor control for metastatic renal cell cancer generally considered radioresistant according to the classic radiobiologic ranking.« less

  17. Initial Results of Hypofractionated Carbon Ion Radiotherapy for Cholangiocarcinoma.

    PubMed

    Abe, Takanori; Shibuya, Kei; Koyama, Yoshinori; Okamoto, Masahiko; Kiyohara, Hiroki; Katoh, Hiroyuki; Shimada, Hirohumi; Kuwano, Hiroyuki; Ohno, Tatsuya; Nakano, Takashi

    2016-06-01

    To report initial results of hypofractionated carbon ion radiotherapy (C-ion RT) for cholangiocarcinoma. Data regarding seven patients with cholangiocarcinoma treated by C-ion RT were analyzed. Prescribed doses were 52.8 Gy [relative biological effectiveness (RBE)] or 60.0 Gy (RBE) in four fractions for intrahepatic cases and 12 fractions for hilar hepatic/close to gastro-intestinal tract cases. Local control and overall survival were evaluated and toxicity was graded using Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up period was 16 months. There were two patients with stage I cancer, one with stage II, one with stage III, and three with stage IVA. Local control was achieved in five out of seven patients (71%) and survival was maintained in six out of seven patients (86%). There were no occurrences of acute or late toxicity of grade 3 or higher. Initial results show that hypofractionated C-ion RT appears to be tolerated and effective for cholangiocarcinoma. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  18. Image Fusion for Radiosurgery, Neurosurgery and Hypofractionated Radiotherapy.

    PubMed

    Inoue, Hiroshi K; Nakajima, Atsushi; Sato, Hiro; Noda, Shin-Ei; Saitoh, Jun-Ichi; Suzuki, Yoshiyuki

    2015-03-01

    Precise target detection is essential for radiosurgery, neurosurgery and hypofractionated radiotherapy because treatment results and complication rates are related to accuracy of the target definition. In skull base tumors and tumors around the optic pathways, exact anatomical evaluation of cranial nerves are important to avoid adverse effects on these structures close to lesions. Three-dimensional analyses of structures obtained with MR heavy T2-images and image fusion with CT thin-sliced sections are desirable to evaluate fine structures during radiosurgery and microsurgery. In vascular lesions, angiography is most important for evaluations of whole structures from feeder to drainer, shunt, blood flow and risk factors of bleeding. However, exact sites and surrounding structures in the brain are not shown on angiography. True image fusions of angiography, MR images and CT on axial planes are ideal for precise target definition. In malignant tumors, especially recurrent head and neck tumors, biologically active areas of recurrent tumors are main targets of radiosurgery. PET scan is useful for quantitative evaluation of recurrences. However, the examination is not always available at the time of radiosurgery. Image fusion of MR diffusion images with CT is always available during radiosurgery and useful for the detection of recurrent lesions. All images are fused and registered on thin sliced CT sections and exactly demarcated targets are planned for treatment. Follow-up images are also able to register on this CT. Exact target changes, including volume, are possible in this fusion system. The purpose of this review is to describe the usefulness of image fusion for 1) skull base, 2) vascular, 3) recurrent target detection, and 4) follow-up analyses in radiosurgery, neurosurgery and hypofractionated radiotherapy.

  19. Image Fusion for Radiosurgery, Neurosurgery and Hypofractionated Radiotherapy

    PubMed Central

    Nakajima, Atsushi; Sato, Hiro; Noda, Shin-ei; Saitoh, Jun-ichi; Suzuki, Yoshiyuki

    2015-01-01

    Precise target detection is essential for radiosurgery, neurosurgery and hypofractionated radiotherapy because treatment results and complication rates are related to accuracy of the target definition. In skull base tumors and tumors around the optic pathways, exact anatomical evaluation of cranial nerves are important to avoid adverse effects on these structures close to lesions. Three-dimensional analyses of structures obtained with MR heavy T2-images and image fusion with CT thin-sliced sections are desirable to evaluate fine structures during radiosurgery and microsurgery. In vascular lesions, angiography is most important for evaluations of whole structures from feeder to drainer, shunt, blood flow and risk factors of bleeding. However, exact sites and surrounding structures in the brain are not shown on angiography. True image fusions of angiography, MR images and CT on axial planes are ideal for precise target definition. In malignant tumors, especially recurrent head and neck tumors, biologically active areas of recurrent tumors are main targets of radiosurgery. PET scan is useful for quantitative evaluation of recurrences. However, the examination is not always available at the time of radiosurgery. Image fusion of MR diffusion images with CT is always available during radiosurgery and useful for the detection of recurrent lesions. All images are fused and registered on thin sliced CT sections and exactly demarcated targets are planned for treatment. Follow-up images are also able to register on this CT. Exact target changes, including volume, are possible in this fusion system. The purpose of this review is to describe the usefulness of image fusion for 1) skull base, 2) vascular, 3) recurrent target detection, and 4) follow-up analyses in radiosurgery, neurosurgery and hypofractionated radiotherapy. PMID:26180676

  20. Hypofractionated accelerated radiotherapy (HART) with concurrent and adjuvant temozolomide in newly diagnosed glioblastoma: a phase II randomized trial (HART-GBM trial).

    PubMed

    Mallick, Supriya; Kunhiparambath, Haresh; Gupta, Subhash; Benson, Rony; Sharma, Seema; Laviraj, M A; Upadhyay, Ashish Datt; Julka, Pramod Kumar; Sharma, Dayanand; Rath, Goura Kishor

    2018-06-23

    Maximal safe surgical resection followed by adjuvant chemoradiation has been standard for newly diagnosed glioblastoma multiforme (GBM). Hypofractionated accelerated radiotherapy (HART) has the potential to improve outcome as it reduces the overall treatment time and increases the biological effective dose. Between October 2011 and July 2017, a total of 89 newly diagnosed GBM patients were randomized to conventional fractionated radiotherapy (CRT) or HART. Radiotherapy was delivered in all patients with a three-dimensional conformal radiotherapy technique in CRT arm (60 Gy in 30 fractions over 6 weeks @ 2 Gy/per fraction) or simultaneous integrated boost intensity modulated radiotherapy in HART arm (60 Gy in 20 fractions over 4 weeks @ 3 Gy/per fraction to high-risk planning target volume (PTV) and 50 Gy in 20 fractions over 4 weeks @ 2.5 Gy/per fraction to low-risk PTV). The primary endpoint of the trial was overall survival (OS). After a median follow-up of 11.4 months (Range: 2.9-42.5 months), 26 patients died and 39 patients had progression of the disease. Median OS for the entire cohort was 23.4 months. Median OS in the CRT and HART arms were 18.07 months (95% CI 14.52-NR) and 25.18 months (95% CI 12.89-NR) respectively, p = 0.3. Median progression free survival (PFS) for the entire cohort was 13.5 months (Range: 11.7-15.7 months). In multivariate analysis patients younger than 40 years of age, patients with a gross total resection of tumor and a mutated IDH-1 had significantly better OS. PFS was significantly better for patients with a gross total resection of tumor and a mutated IDH-1. All patients included in the trial completed the planned course of radiation. Only two patients required hospital admission for features of raised intracranial tension. One patient in the HART arm required treatment interruption. HART is comparable to CRT in terms of survival outcome. HART arm had no excess treatment interruption and minimal toxicity. Dose

  1. The use of hypofractionated intensity-modulated irradiation in the treatment of glioblastoma multiforme: preliminary results of a prospective trial.

    PubMed

    Sultanem, Khalil; Patrocinio, Horacio; Lambert, Christine; Corns, Robert; Leblanc, Richard; Parker, William; Shenouda, George; Souhami, Luis

    2004-01-01

    Despite major advances in treatment modalities, the prognosis of patients with glioblastoma multiforme (GBM) remains poor. Exploring hypofractionated regimens to replace the standard 6-week radiotherapy schedule is an attractive strategy as an attempt to prevent accelerated tumor cell repopulation. There is equally interest in dose escalation to the gross tumor volume where the majority of failures occur. We report our preliminary results using hypofractionated intensity-modulated accelerated radiotherapy regimen in the treatment of patients with GBM. Between July 1998 and December 2001, 25 patients with histologically proven diagnosis of GBM, Karnofsky performance status > or =60, and a postoperative tumor volume < or =110 cm3 were treated with a hypofractionated accelerated course of radiotherapy. The gross tumor volume (GTV) was defined as the contrast-enhancing lesion on the postoperative MRI T1-weighted images with the latter fused with computed tomography images for treatment planning. The planning target volume was defined as GTV + 1.5-cm margin. Using forward-planning intensity modulation (step-and-shoot technique), 60 Gy in 20 daily fractions of 3 Gy each were given to the GTV, whereas the planning target volume received a minimum of 40 Gy in 20 fractions of 2 Gy each at its periphery. Treatments were delivered over a 4-week period using 5 daily fractions per week. Dose was prescribed at the isocenter (ICRU point). Three beam angles were used in all of the cases. Treatments were well tolerated. Acute toxicity was limited to increased brain edema during radiotherapy in 2 patients who were on tapering doses of corticosteroids. This was corrected by increasing the steroid dose. At a median follow-up of 8.8 months, no late toxicity was observed. One patient experienced visual loss at 9 months after completion of treatment. MRI suggested nonspecific changes to the optic chiasm. On review of the treatment plan, the total dose to the optic chiasm was confirmed to

  2. Retrospective study of canine nasal tumor treated with hypofractionated radiotherapy.

    PubMed

    Maruo, Takuya; Shida, Takuo; Fukuyama, Yasuhiro; Hosaka, Soshi; Noda, Masashi; Ito, Tetsuro; Sugiyama, Hiroki; Ishikawa, Takeshi; Madarame, Hiroo

    2011-02-01

    The object of this study was to evaluate hypofractionated multiportal field and two-portion (rostral and caudal portions divided by the eyelid) radiation therapy for canine nasal tumors. Sixty-three dogs underwent multiportal hypofractionated radiation therapy. The radiation field was divided into rostral and caudal portions by the eyelid. Treatments were performed four times for 57 dogs. The median irradiation dose/fraction was 8 Gy (range, 5-10 Gy); the median total dose was 32 Gy (10-40 Gy). Improvement of clinical symptoms was achieved in 53 (84.1%) of 63 cases. Median survival time was 197 days (range, 2-1,080 days). Median survival times with and without destruction of the cribriform plate before radiotherapy were 163 and 219 days, respectively. There was no significant difference between them. No other factors were related to survival according to a univariate analysis. All radiation side effects, except one, were grade I according to the VRTOG classification. It was not necessary to treat any dogs for skin side effects. One dog (1.6%) developed an oronasal fistula 1 year after completion of radiation therapy. This radiation protocol may be useful in reducing radiation side effects in dogs with cribriform plate destruction.

  3. Local Tumor Control, Visual Acuity, and Survival After Hypofractionated Stereotactic Photon Radiotherapy of Choroidal Melanoma in 212 Patients Treated Between 1997 and 2007

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dunavoelgyi, Roman; Dieckmann, Karin, E-mail: karin.dieckmann@meduniwien.ac.at; Gleiss, Andreas

    2011-09-01

    Purpose: To evaluate long-term local tumor control, visual acuity, and survival after hypofractionated linear accelerator-based stereotactic photon radiotherapy in patients with choroidal melanoma. Methods and Materials: Between 1997 and 2007, 212 patients with choroidal melanoma unsuitable for ruthenium-106 brachytherapy or local resection were treated stereotactically at a linear accelerator with 6-MV photon beams at the Medical University of Vienna in five fractions over 7 days. Twenty-four patients received a total dose of 70 Gy (five fractions of 14 Gy), 158 a total dose of 60 Gy (five fractions of 12 Gy) and 30 patients a total dose of 50 Gymore » (five fractions of 10 Gy) applied on the 80% isodose. Ophthalmologic examinations were performed at baseline and every 3 months in the first 2 years, every 6 months until 5 years, and once a year thereafter until 10 years after radiotherapy. Assessment of visual acuity, routine ophthalmologic examinations, and measurement of tumor base dimension and height using standardized A-scan and B-scan echography were done at each visit. Funduscopy and fluorescein angiography were done when necessary to document tumor response. Results: Median tumor height and volume decreased from 4.8 mm and 270.7 mm{sup 3} at baseline to 2.6 mm and 86.6 mm{sup 3} at the last individual follow-up, respectively (p < 0.001, p < 0.001). Median visual acuity decreased from 0.55 at baseline to hand motion at the last individual follow-up (p < 0.001). Local tumor control was 95.9% after 5 years and 92.6% after 10 years. Thirty-two patients developed metastatic disease, and 22 of these patients died during the follow-up period. Conclusion: Hypofractionated stereotactic photon radiotherapy with 70 to 50 Gy delivered in five fractions in 7 days is sufficient to achieve excellent local tumor control in patients with malignant melanoma of the choroid. Disease outcome and vision are comparable to those achieved with proton beam radiotherapy

  4. Toxicity Assessment of Pelvic Intensity-Modulated Radiotherapy With Hypofractionated Simultaneous Integrated Boost to Prostate for Intermediate- and High-Risk Prostate Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCammon, Robert; Rusthoven, Kyle E.; Kavanagh, Brian

    Purpose: To evaluate the toxicity of pelvic intensity-modulated radiotherapy (IMRT) with hypofractionated simultaneous integrated boost (SIB) to the prostate for patients with intermediate- to high-risk prostate cancer. Methods and Materials: A retrospective toxicity analysis was performed in 30 consecutive patients treated definitively with pelvic SIB-IMRT, all of whom also received androgen suppression. The IMRT plans were designed to deliver 70 Gy in 28 fractions (2.5 Gy/fraction) to the prostate while simultaneously delivering 50.4 Gy in 28 fractions (1.8 Gy/fraction) to the pelvic lymph nodes. The National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0, was used to scoremore » toxicity. Results: The most common acute Grade 2 events were cystitis (36.7%) and urinary frequency/urgency (26.7%). At a median follow-up of 24 months, late toxicity exceeding Grade 2 in severity was uncommon, with two Grade 3 events and one Grade 4 event. Grade 2 or greater acute bowel toxicity was associated with signficantly greater bowel volume receiving {>=}25 Gy (p = .04); Grade 2 or greater late bowel toxicity was associated with a higher bowel maximal dose (p = .04) and volume receiving {>=}50 Gy (p = .02). Acute or late bladder and rectal toxicity did not correlate with any of the dosimetric parameters examined. Conclusion: Pelvic IMRT with SIB to the prostate was well tolerated in this series, with low rates of Grade 3 or greater acute and late toxicity. SIB-IMRT combines pelvic radiotherapy and hypofractionation to the primary site and offers an accelerated approach to treating intermediate- to high-risk disease. Additional follow-up is necessary to fully define the long-term toxicity after hypofractionated, whole pelvic treatment combined with androgen suppression.« less

  5. Salvage Treatment With Hypofractionated Radiotherapy in Patients With Recurrent Small Hepatocellular Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bae, Sun Hyun; Park, Hee Chul, E-mail: rophc@skku.edu; Lim, Do Hoon

    2012-03-15

    Purpose: To investigate the rates of tumor response and local control in patients with recurrent small hepatocellular carcinoma (HCC) treated with hypofractionated radiotherapy (RT) as a salvage treatment and to evaluate treatment-related toxicities. Methods and Materials: Between 2006 and 2009, a total of 20 patients with recurrent small HCC were treated with hypofractionated RT after the failure of previous treatment. The eligibility criteria for hypofractionated RT were as follows: 1) HCC less than 5 cm, 2) HCC not adjacent to critical organs, 3) HCC without portal vein tumor thrombosis, and 4) less than 15% of normal liver volume that wouldmore » be irradiated with 50% of prescribed dose. The RT dose was 50 Gy in 10 fractions. The tumor response was determined by CT scans performed 3 months after the end of RT. Results: The median follow-up period after RT was 22 months. The overall survival rates at 1 and 2 years were 100% and 87.9%, respectively. Complete response (CR) was achieved in seven of 20 lesions (35%) evaluated by CT scans performed 3 months after the end of RT. In-field local control was achieved in 85% of patients. Fourteen patients (70%) developed intra-hepatic metastases. Six patients developed grade 1 nausea or anorexia during RT, and two patients had progression of ascites after RT. There was no grade 3 or greater treatment-related toxicities. Conclusions: The current study showed a favorable outcome with respect to hypofractionated RT for small HCC. Partial liver irradiation with 50 Gy in 10 fractions is considered tolerable without severe complications.« less

  6. Hypo-fractionated stereotactic radiotherapy of five fractions with linear accelerator for vestibular schwannomas: A systematic review and meta-analysis.

    PubMed

    Nguyen, Thien; Duong, Courtney; Sheppard, John P; Lee, Seung Jin; Kishan, Amar U; Lee, Percy; Tenn, Stephen; Chin, Robert; Kaprealian, Tania B; Yang, Isaac

    2018-03-01

    Vestibular schwannomas (VS) are benign tumors stemming from the eighth cranial nerve. Treatment options for VS include conservative management, microsurgery, stereotactic radiosurgery, and fractionated radiotherapy. Though microsurgery has been the standard of care for larger lesions, hypo-fractionated stereotactic radiotherapy (hypo-FSRT) is an emerging modality. However, its clinical efficacy and safety have yet to be established. We conducted a systematic review and meta-analysis of manuscripts indexed in PubMed, Scopus, Web of Science, Embase, and Cochrane databases reporting outcomes of VS cases treated with hypo-FSRT. Five studies representing a total of 228 patients were identified. Across studies, the pooled rates of tumor control, hearing, facial nerve, and trigeminal nerve preservation were 95%, 37%, 97%, and 98%. No instances of malignant induction were observed at median follow-up of 34.8 months. Complications included trigeminal neuropathy (n = 3), maxillary paresthesia (n = 1), neuralgia (n = 1), vestibular dysfunction (n = 1), radionecrosis (n = 1), and hydrocephalus (n = 1). Hypo-FSRT may be another useful approach to manage VS, but studies with extended follow-up times are required to establish long-term safety. Copyright © 2018. Published by Elsevier B.V.

  7. Hypofractionated Radiotherapy Is Superior to Conventional Fractionation in an Orthotopic Model of Anaplastic Thyroid Cancer.

    PubMed

    Oweida, Ayman; Phan, Andy; Vancourt, Benjamin; Robin, Tyler; Hararah, Mohammad K; Bhatia, Shilpa; Milner, Dallin; Lennon, Shelby; Pike, Laura; Raben, David; Haugen, Bryan; Pozdeyev, Nikita; Schweppe, Rebecca; Karam, Sana D

    2018-06-01

    Anaplastic thyroid cancer (ATC) is an aggressive and highly lethal disease with poor outcomes and resistance to therapy. Despite multimodality treatment, including radiation therapy and chemotherapy, response rates remain <15%, with a median time to progression of less than three months. Recent advances in radiotherapy (RT) delivery and gene-expression profiling may help guide patient selection for personalized therapy. The purpose of this study was to characterize the response to radiation in a panel of ATC cell lines and to test alternative RT fractionation schedules for overcoming radioresistance. The cellular response to radiation was characterized based on clonogenic assays. Radiation response was correlated with microarray gene-expression data. Hypofractionated and conventional RT was tested in an orthotopic ATC tumor model, and tumor growth was assayed locally and distantly with in vivo and ex vivo bioluminescence imaging. A spectrum of radiosensitivities was observed in ATC cell lines. Radioresistant cell lines had higher levels of CXCR4 compared to radiosensitive cell lines. Compared to conventionally fractionated RT, hypofractionated RT resulted in significantly improved tumor growth delay, decreased regional and distant metastases, and improved overall survival. The findings demonstrate the heterogeneity of response to radiation in ATC tumors and the superiority of hypofractionated RT in improving local control, metastatic spread, and survival in preclinical models. These data support the design of clinical trials targeting radioresistant pathways in combination with hypofractionated RT.

  8. Use of hypofractionated post-mastectomy radiotherapy reduces health costs by over $2000 per patient: An Australian perspective.

    PubMed

    Mortimer, Joshua W; McLachlan, Craig S; Hansen, Carmen J; Assareh, Hassan; Last, Andrew; McKay, Michael J; Shakespeare, Thomas P

    2016-02-01

    The most recent clinical practice guidelines released by Cancer Australia draw attention to unanswered questions concerning the health economic considerations associated with hypofractionated radiotherapy. This study aimed to quantify and compare the healthcare costs at a regional Australian radiotherapy institute with respect to conventionally fractionated post-mastectomy radiotherapy (Cf-PMRT) versus hypofractionated post-mastectomy radiotherapy (Hf-PMRT) administration. Medical records of 196 patients treated with post-mastectomy radiotherapy at the NSW North Coast Cancer Institute from February 2008 to June 2014 were retrospectively reviewed. Australian Medicare item numbers billed for patients receiving either Cf-PMRT of 50 Gy in 25 daily fractions or Hf-PMRT of 40.05 Gy in 15 daily fractions were calculated. Decision tree analysis was used to model costs. Independent-samples t-tests and Mann-Whitney U-tests were used to compare crude average costs for Cf-PMRT and Hf-PMRT and determine which treatment components accounted for any differences. Hf-PMRT, with or without irradiation to the regional lymph nodes, was associated with significantly reduced Medicare costs ($5613 AUD per patient for Hf-PMRT vs $8272 AUD per patient for Cf-PMRT; P < 0.001). Savings associated with Hf-PMRT ranged from $1353 (22.1%) for patients receiving no regional irradiation to $2898 (32.0%) for patients receiving both axillary and supraclavicular therapy. Hf-PMRT results in a significant reduction in the financial costs associated with treating breast cancer patients in a regional Australian setting when compared with Cf-PMRT. © 2015 The Royal Australian and New Zealand College of Radiologists.

  9. New techniques for assessing response after hypofractionated radiotherapy for lung cancer

    PubMed Central

    Mattonen, Sarah A.; Huang, Kitty; Ward, Aaron D.; Senan, Suresh

    2014-01-01

    Hypofractionated radiotherapy (HFRT) is an effective and increasingly-used treatment for early stage non-small cell lung cancer (NSCLC). Stereotactic ablative radiotherapy (SABR) is a form of HFRT and delivers biologically effective doses (BEDs) in excess of 100 Gy10 in 3-8 fractions. Excellent long-term outcomes have been reported; however, response assessment following SABR is complicated as radiation induced lung injury can appear similar to a recurring tumor on CT. Current approaches to scoring treatment responses include Response Evaluation Criteria in Solid Tumors (RECIST) and positron emission tomography (PET), both of which appear to have a limited role in detecting recurrences following SABR. Novel approaches to assess response are required, but new techniques should be easily standardized across centers, cost effective, with sensitivity and specificity that improves on current CT and PET approaches. This review examines potential novel approaches, focusing on the emerging field of quantitative image feature analysis, to distinguish recurrence from fibrosis after SABR. PMID:24688782

  10. Hypofractionated radiation therapy for prostate cancer: The McGill University Health Center experience.

    PubMed

    Barbosa Neto, O; Souhami, L; Faria, S

    2015-10-01

    In 2002, at the McGill University Health Centre, we began a program of hypofractionated radiotherapy for patients with low risk prostate cancer as an alternative to conventionally fractionated radiotherapy. Our initial hypofractionation regimen was 66 Gy given in 22 fractions, prescribed to the isocenter, delivered with 3D-conformal radiotherapy plan. The clinical target volume was the prostate gland and the planning target volume consisted of the clinical target volume plus a 7-mm margin in all directions. Hormonal therapy was not given to any patient. The long-term results for this group of patients confirmed the feasibility, good tolerance and excellent disease control of the regimen with the extra-benefit of being convenient to both patients and the health system by shortening treatment duration. The outcomes of this approach stimulated us to use hypofractionation in patients with intermediate-risk. Analysis of 100 intermediate-risk patients receiving our hypofractionated radiotherapy regimen (no hormones) shows, at median follow-up of 75 months, 8-year biochemical recurrence free and cancer specific survival rates of 90% and 95%, respectively, with acceptable toxicity. Our technique changed from 3D to intensity modulated radiotherapy with the dose adjusted to 60 Gy in 20 fractions. Lastly, we have expanded the program to high-risk patients where IMRT treatments are given to the pelvic nodes (44 Gy in 20 fractions) with a simultaneous integrated boost delivery to the prostate (60 Gy in the same 20 fractions). Our long-term results have shown that moderate hypofractionated radiotherapy for prostate cancer is safe and provides good tumor control comparable to high-dose conventionally fractionated radiotherapy. This hypofractionated regimen has been routinely used in our institution. Copyright © 2015 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  11. Norm- and hypo-fractionated radiotherapy is capable of activating human dendritic cells.

    PubMed

    Kulzer, Lorenz; Rubner, Yvonne; Deloch, Lisa; Allgäuer, Andrea; Frey, Benjamin; Fietkau, Rainer; Dörrie, Jan; Schaft, Niels; Gaipl, Udo S

    2014-10-01

    Despite the transient immunosuppressive properties of local radiotherapy (RT), this classical treatment modality of solid tumors is capable of inducing immunostimulatory forms of tumor-cell death. The resulting 'immunotoxicity' in the tumor, but not in healthy tissues, may finally lead to immune-mediated destruction of the tumor. However, little is known about the best irradiation scheme in this setting. This study examines the immunological effects of differently irradiated human colorectal tumor cells on human monocyte-derived dendritic cells (DC). Human SW480 tumor cells were irradiated with a norm-fractionation scheme (5 × 2 Gy), a hypo-fractionated protocol (3 × 5 Gy), and with a high single irradiation dose (radiosurgery; 1 × 15 Gy). Subsequently, human immature DC (iDC) were co-incubated with supernatants (SN) of these differently treated tumor cells. Afterwards, DC were analyzed regarding the expression of maturation markers, the release of cytokines, and the potential to stimulate CD4(+) T-cells. The co-incubation of iDC with SN of tumor cells exposed to norm- or hypo-fractionated RT resulted in a significantly increased secretion of the immune activating cytokines IL-12p70, IL-8, IL-6, and TNFα, compared to iDC co-incubated with SN of tumor cells that received a high single irradiation dose or were not irradiated. In addition, DC-maturation markers CD80, CD83, and CD25 were also exclusively elevated after co-incubation with the SN of fractionated irradiated tumor cells. Furthermore, the SN of tumor cells that were irradiated with norm- or hypo-fractionated RT triggered iDC to stimulate CD4(+) T-cells not only in an allogenic, but also in an antigen-specific manner like mature DC. Collectively, these results demonstrate that norm- and hypo-fractionated RT induces a fast human colorectal tumor-cell death with immunogenic potential that can trigger DC maturation and activation in vitro. Such findings may contribute to the improvement of

  12. [Clinical experience in image-guided ultra-conformal hypofractionated radiotherapy in case of metastatic diseases at the University of Pécs].

    PubMed

    László, Zoltán; Boronkai, Árpád; Lõcsei, Zoltán; Kalincsák, Judit; Szappanos, Szabolcs; Farkas, Róbert; Al Farhat, Yousuf; Sebestyén, Zsolt; Sebestyén, Klára; Kovács, Péter; Csapó, László; Mangel, László

    2015-06-01

    With the development of radiation therapy technology, the utilization of more accurate patient fixation, inclusion of PET/CT image fusion into treatment planning, 3D image-guided radiotherapy, and intensity-modulated dynamic arc irradiation, the application of hypofractionated stereotactic radiotherapy can be extended to specified extracranial target volumes, and so even to the treatment of various metastases. Between October 2012 and August 2014 in our institute we performed extracranial, hypofractionated, image-többguided radiotherapy with RapidArc system for six cases, and 3D conformal multifield technique for one patient with Novalis TX system in case of different few-numbered and slow-growing metastases. For the precise definition of the target volumes we employed PET/CT during the treatment planning procedure. Octreotid scan was applied in one carcinoid tumour patient. Considering the localisation of the metastases and the predictable motion of the organs, we applied 5 to 20 mm safety margin during the contouring procedure. The average treatment volume was 312 cm3. With 2.5-3 Gy fraction doses we delivered 39-45 Gy total dose, and the treatment duration was 2.5 to 3 weeks. The image guidance was carried out via ExacTrac, and kV-Cone Beam CT equipment based on an online protocol, therefore localisation differences were corrected before every single treatment. The patients tolerated the treatments well without major (Gr>2) side effects. Total or near total regression of the metastases was observed at subsequent control examinations in all cases (the median follow-up time was 5 months). According to our first experience, extracranial, imageguided hypofractionated radiotherapy is well-tolerated by patients and can be effectively applied in the treatment of slow-growing and few-numbered metastases.

  13. Comparison of Local Recurrence Among Early Breast Cancer Patients Treated With Electron Intraoperative Radiotherapy vs Hypofractionated Photon Radiotherapy an Observational Study.

    PubMed

    Guenzi, Marina; Bonzano, Elisabetta; Corvò, Renzo; Merolla, Francesca; Pastorino, Alice; Cavagnetto, Francesca; Garelli, Stefania; Cutolo, Carlo Alberto; Friedman, Daniele; Belgioia, Liliana

    2018-01-01

    To evaluate local recurrence (LR) in women with early breast cancer (BC) who underwent intraoperative radiation therapy with electrons particles (IORT-E) or adjuvant hypofractionated external radiotherapy (HYPOFX). We retrospectively analyzed 470 patients with early BC treated at our center from September 2009 to December 2012. 235 women were treated with breast-conserving surgery and immediate IORT-E (21 Gy/1 fraction) while 235 patients underwent wide excision followed by hypofractionated whole-breast irradiation. Radiotherapy modality was chosen according to an individualized decision based on tumor features, stage, technical feasibility, age, and acceptance to be enrolled in the IORT-E group. After a median follow-up of 6 years, we observed 8 (3.4%) and 1 (0.42%) LR in the IORT-E and in the HYPOFX group ( p  = 0.02), respectively. The two groups differed in the prevalence of clinical characteristics ( p  < 0.05): age, tumor size, surgical margins, receptors, ki67, and histology. 4 and 1 woman in the IORT-E and HYPOFX group died of BC, respectively ( p  = 0.167). OS and DFS hazard ratio [HR] were 2.14 (95% IC, 1.10-4.15) and 2.09 (95% IC, 1.17-3.73), respectively. Our comparison showed that IORT-E and HYPOFX are two effective radiotherapy modalities after conservative surgery in early BC. However, at 6 years a significant higher rate of LR occurred in patients submitted to IORT-E with respect to HYPOFX. This finding may be correlated to some subsets of patients who, depending on the biological characteristics of the BC, may be less suitable to IORT-E.

  14. Ten-year results of accelerated hypofractionated adjuvant whole-breast radiation with concomitant boost to the lumpectomy cavity after conserving surgery for early breast cancer.

    PubMed

    Cante, Domenico; Petrucci, Edoardo; Sciacero, Piera; Piva, Cristina; Ferrario, Silvia; Bagnera, Silvia; Patania, Sebastiano; Mondini, Guido; Pasquino, Massimo; Casanova Borca, Valeria; Vellani, Giorgio; La Porta, Maria Rosa; Franco, Pierfrancesco

    2017-09-01

    Accelerated hypofractionated whole-breast radiotherapy (WBRT) is considered a standard therapeutic option for early breast cancer (EBC) in the postoperative setting after breast conservation (BCS). A boost to the lumpectomy cavity may further increase local control. We herein report on the 10-year results of a series of EBC patients treated after BCS with hypofractionated WBRT with a concomitant photon boost to the surgical bed over 4 weeks. Between 2005 and 2007, 178 EBC patients were treated with a basic course of radiotherapy consisting of 45 Gy to the whole breast in 20 fractions (2.25 Gy daily) with an additional boost dose of 0.25 Gy delivered concomitantly to the lumpectomy cavity, for an additional dose of 5 Gy. Median follow-up period was 117 months. At 10-year, overall, cancer-specific, disease-free survival and local control were 92.2% (95% CI 88.7-93.4%), 99.2% (95% CI 96.7-99.7%), 95.5% (95% CI 91.2-97.2%) and 97.3% (95% CI 94.5-98.9%), respectively. Only eight patients recurred. Four in-breast recurrences, two axillary node relapses and two metastatic localizations were observed. Fourteen patients died during the observation period due to other causes while breast cancer-related deaths were eight. At last follow-up, ≥G2 fibrosis and telangiectasia were seen in 7% and 5% of patients. No major lung and heart toxicities were observed. Cosmetic results were excellent/good in 87.8% of patients and fair/poor in 12.2%. Hypofractionated WBRT with concomitant boost to the lumpectomy cavity after BCS in EBC led to consistent clinical results at 10 years. Hence, it can be considered a valid treatment option in this setting.

  15. Rationale, conduct, and outcome using hypofractionated radiotherapy in prostate cancer

    PubMed Central

    Ritter, Mark

    2008-01-01

    Hypofractionated radiation therapy for prostate cancer has become of increasing interest with the recognition of a potential improvement in therapeutic ratio with treatments delivered in larger-sized fractions. In addition, the associated reduction in fraction number produces attractive cost and patient convenience advantages as well. A still limited but growing number of hypofractionation trials have reported acceptable short-term levels of toxicity and biochemical control, but most have insufficient follow-up to assure the long-term safety and efficacy of this approach. This situation will improve as many currently active trials mature, particularly several high value randomized trials. In contrast, extreme hypofractionation, with schedules delivering only on the order of 5 fractions, is truly in its infancy for prostate cancer, with extremely limited tolerance and efficacy information currently available. Several uncertainties in the radiobiology of hypofractionation mitigate for an organized, cautious investigational approach. The fractionation response (α/β ratio) of prostate cancers and, for that matter, late responding normal tissues, has yet to be rigorously defined. Additionally, the linear quadratic (LQ) model used in the design of hypofractionation schedules is subject to its own uncertainties, particularly with respect to the upper limit of fraction sizes for which it remains valid. Contemporary dose escalated radiation therapy is already highly effective, making it imperative that ongoing and future studies of hypofractionation be carried out in carefully designed, randomized clinical trials. Clinical validation permitting, the adaptation of hypofractionation as a standard of care could profoundly influence future management of localized prostate cancer. PMID:18725112

  16. MO-FG-BRA-05: Dosimetric and Radiobiological Validation of Respiratory Gating in Conventional and Hypofractionated Radiotherapy of the Lung: Effect of Dose, Dose Rate, Gating Window and Breathing Pattern

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cervino, L; Soultan, D; Pettersson, N

    2016-06-15

    Purpose: to evaluate the dosimetric and radiobiological consequences from having different gating windows, dose rates, and breathing patterns in gated VMAT lung radiotherapy. Methods: A novel 3D-printed moving phantom with central high and peripheral low tracer uptake regions was 4D FDG-PET/CT-scanned using ideal, patient-specific regular, and irregular breathing patterns. A scan of the stationary phantom was obtained as a reference. Target volumes corresponding to different uptake regions were delineated. Simultaneous integrated boost (SIB) 6 MV VMAT plans were produced for conventional and hypofractionated radiotherapy, using 30–70 and 100% cycle gating scenarios. Prescribed doses were 200 cGy with SIB to 240more » cGy to high uptake volume for conventional, and 800 with SIB to 900 cGy for hypofractionated plans. Dose rates of 600 MU/min (conventional and hypofractionated) and flattening filter free 1400 MU/min (hypofractionated) were used. Ion chamber measurements were performed to verify delivered doses. Vials with A549 cells placed in locations matching ion chamber measurements were irradiated using the same plans to measure clonogenic survival. Differences in survival for the different doses, dose rates, gating windows, and breathing patterns were analyzed. Results: Ion chamber measurements agreed within 3% of the planned dose, for all locations, breathing patterns and gating windows. Cell survival depended on dose alone, and not on gating window, breathing pattern, MU rate, or delivery time. The surviving fraction varied from approximately 40% at 2Gy to 1% for 9 Gy and was within statistical uncertainty relative to that observed for the stationary phantom. Conclusions: Use of gated VMAT in PET-driven SIB radiotherapy was validated using ion chamber measurements and cell survival assays for conventional and hypofractionated radiotherapy.« less

  17. Hypofractionated Radiotherapy for Complicated Bone Metastases in Patients with Poor Performance Status: A Phase II International Trial.

    PubMed

    Silva, Mauricio F; Marta, Gustavo N; Lisboa, Felipe P C; Watte, Guilherme; Trippa, Fabio; Maranzano, Ernesto; da Motta, Neiro W; Popovic, Marko; Ha, Tuan; Burmeister, Bryan; Chow, Edward

    2017-06-01

    Purpose To evaluate the efficacy and safety of hypofractionated radiotherapy (16 Gy in 2 fractions, 1 week apart) in patients with complicated bone metastases and poor performance status. Methods A prospective single-arm phase II clinical trial was conducted from July 2014 to May 2016. The primary endpoint was pain response as defined in the International Consensus on Palliative Radiotherapy Endpoints. Secondary endpoints included quality of life as measured by quality of life questionnaire (QLQ) PAL-15 and QLQ-BM22 European Organisation for Research and Treatment of Cancer guidelines, pain flare, adverse events, re-irradiation, and skeletal complications. Results Fifty patients were enrolled. There were 23 men with a median age of 58 years (range 26-86). Of the 50 patients, 38 had an extraosseous soft tissue component, 18 needed postsurgical radiation, 3 had neuropathic pain, and 3 had an impending fracture in a weight-bearing bone. At 2 months, 33 patients were alive (66%). Four (12.5%) had a complete response and 12 (37.5%) had a partial response. A statistically significant improvement was seen in the functional interference (p = 0.01) and psychosocial aspects (p = 0.03) of the BM22. No patient had spinal cord compression. One patient required surgery for pathologic fracture, and another re-irradiation. Conclusions Hypofractionated radiotherapy (16 Gy in 2 fractions of 8 Gy 1 week apart) achieved satisfactory pain relief and safety results in patients with complicated bone metastases and poor performance status.

  18. Radiogenic Side Effects After Hypofractionated Stereotactic Photon Radiotherapy of Choroidal Melanoma in 212 Patients Treated Between 1997 and 2007

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dunavoelgyi, Roman; Dieckmann, Karin; Gleiss, Andreas

    2012-05-01

    Purpose: To evaluate side effects of hypofractionated stereotactic photon radiotherapy for patients with choroidal melanoma. Patients and Methods: Two hundred and twelve patients with choroidal melanoma unsuitable for ruthenium-106 brachytherapy or local resection were treated stereotactically at the Medical University of Vienna between 1997 and 2007 with a Linac with 6-MV photon beams in five fractions with 10, 12, or 14 Gy per fraction. Examinations for radiogenic side effects were performed at baseline and every 3 months in the first 2 years, then every 6 months until 5 years and then once a year thereafter until 10 years after radiotherapy.more » Adverse side effects were assessed using slit-lamp examination, funduscopy, gonioscopy, tonometry, and, if necessary, fundus photography and fluorescein angiography. Evaluations of incidence of side effects are based on an actuarial analysis. Results: One hundred and eighty-nine (89.2%) and 168 (79.2%) of the tumors were within 3 mm of the macula and the optic disc, respectively. The five most common radiotherapy side effects were retinopathy and optic neuropathy (114 cases and 107 cases, respectively), cataract development (87 cases), neovascular glaucoma (46 cases), and corneal epithelium defects (41 cases). In total, 33.6%, 38.5%, 51.2%, 75.5%, and 77.6% of the patients were free of any radiation retinopathy, optic neuropathy, cataract, neovascular glaucoma, or corneal epithelium defects 5 years after radiotherapy, respectively. Conclusion: In centrally located choroidal melanoma hypofractionated stereotactic photon radiotherapy shows a low to moderate rate of adverse long-term side effects comparable with those after proton beam radiotherapy. Future fractionation schemes should seek to further reduce adverse side effects rate while maintaining excellent local tumor control.« less

  19. Quality of Life After Hypofractionated Concomitant Intensity-Modulated Radiotherapy Boost for High-Risk Prostate Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quon, Harvey; Department of Radiation Oncology, University of Toronto, Toronto, ON; Cheung, Patrick C.F., E-mail: patrick.cheung@sunnybrook.ca

    Purpose: To evaluate the change in health-related quality of life (QOL) of patients with high-risk prostate cancer treated using hypofractionated radiotherapy combined with long-term androgen deprivation therapy. Methods and Materials: A prospective Phase I-II study enrolled patients with any of the following: clinical Stage T3 disease, prostate-specific antigen level {>=}20 ng/mL, or Gleason score 8-10. Radiotherapy consisted of 45 Gy (1.8 Gy per fraction) to the pelvic lymph nodes with a concomitant 22.5 Gy intensity-modulated radiotherapy boost to the prostate, for a total of 67.5 Gy (2.7 Gy per fraction) in 25 fractions over 5 weeks. Daily image guidance wasmore » performed using three gold seed fiducials. Quality of life was measured using the Expanded Prostate Cancer Index Composite (EPIC), a validated tool that assesses four primary domains (urinary, bowel, sexual, and hormonal). Results: From 2004 to 2007, 97 patients were treated. Median follow-up was 39 months. Compared with baseline, at 24 months there was no statistically significant change in the mean urinary domain score (p = 0.99), whereas there were decreases in the bowel (p < 0.01), sexual (p < 0.01), and hormonal (p < 0.01) domains. The proportion of patients reporting a clinically significant difference in EPIC urinary, bowel, sexual, and hormonal scores at 24 months was 27%, 31%, 55%, and 60%, respectively. However, moderate and severe distress related to these symptoms was minimal, with increases of only 3% and 5% in the urinary and bowel domains, respectively. Conclusions: Hypofractionated radiotherapy combined with long-term androgen deprivation therapy was well tolerated. Although there were modest rates of clinically significant patient-reported urinary and bowel toxicity, most of this caused only mild distress, and moderate and severe effects on QOL were limited. Additional follow-up is ongoing to characterize long-term QOL.« less

  20. Hypofractionated stereotactic radiotherapy in combination with bevacizumab or fotemustine for patients with progressive malignant gliomas.

    PubMed

    Minniti, Giuseppe; Agolli, Linda; Falco, Teresa; Scaringi, Claudia; Lanzetta, Gaetano; Caporello, Paola; Osti, Mattia Falchetto; Esposito, Vincenzo; Enrici, Riccardo Maurizi

    2015-05-01

    To evaluate the efficacy of hypofractionated stereotactic radiotherapy performed as reirradiation in combination with fotemustine or bevacizumab as salvage treatment in patients with recurrent malignant glioma. Between May 2006 and December 2013, 54 patients with recurrent malignant glioma received hypofractionated stereotactic radiotherapy (HSRT, 25 Gy in 5-Gy fractions) plus either fotemustine or bevacizumab at University of Rome Sapienza, Sant'Andrea Hospital. All patients had Karnofsky performance score (KPS) ≥ 60 and were previously treated with standard chemoradiotherapy. Forty-two patients had a GBM and 12 patients had an anaplastic astrocytoma (AA). The median overall survival (OS) time and 12-month OS rates after HSRT was 11 months and 30 % for patients treated with HSRT plus bevacizumab and 8.3 months and 5 % for those treated with HSRT plus fotemustine (p = 0.01). Median PFS times were 4 and 6 months for patients treated with HSRT plus fotemustine or bevacizumab, respectively (p = 0.01). KPS > 70 (p = 0.04), AA histology, and the treatment with bevacizumab were independent favourable prognostic factors for OS. In general, both treatments were well tolerated with relatively low treatment-related toxicity. HSRT combined with bevacizumab or fotemustine may represent a feasible treatment option for patients with progressive malignant gliomas, although most of the tumors recur in a few months. Efficacy of bevacizumab or alkylating agents in combination with different radiation schedules needs to be evaluated in prospective studies.

  1. Tumor Control Outcomes Following Hypofractionated and Single-Dose Stereotactic Image-Guided Intensity-Modulated Radiotherapy for Extracranial Metastases from Renal Cell Carcinoma

    PubMed Central

    Zelefsky, Michael J; Greco, Carlo; Motzer, Robert; Magsanoc, Juan Martin; Pei, Xin; Lovelock, Michael; Mechalakos, Jim; Zatcky, Joan; Fuks, Zvi; Yamada, Yoshiya

    2014-01-01

    Purpose To report tumor local progression-free outcomes following treatment with single-dose image-guided intensity-modulated radiotherapy (SD-IGRT) and hypofractionated regimens for extracranial metastases from renal cell primary tumors. Methods and Materials Between 2004 and 2010, a total of 105 lesions from renal cell carcinomas were treated with either SD-IGRT to prescription doses of 18–24 Gy (median, 24 Gy) or hypofractionation (3 or 5 fractions) with prescription doses ranging between 20 and 30 Gy. The median follow-up was 12 months (range, 1–48 months). Results The overall 3-year actuarial local progression-free survival (LPFS) for all lesions was 44%. The 3-year LPFS for those who received high single-dose (24 Gy; n = 45), low single-dose (< 24 Gy; n = 14), and hypofractionation regimens (n = 46) were 88%, 21%, and 17%, respectively (high single dose versus low single dose, p = 0.001; high single dose versus hypofractionation, p < 0.001). Multivariate analysis revealed the following variables as significant predictors of improved LPFS: dose of 24 Gy compared with lower dose (p = 0.009), and single dose versus hypofractionation (p = 0.008). Conclusion High-dose SD-IGRT is a non-invasive procedure resulting in high probability of local tumor control for metastatic renal cell cancers, generally considered radioresistant according to classical radiobiological ranking. PMID:21596489

  2. Radical-intent hypofractionated radiotherapy for locally advanced non-small-cell lung cancer: a systematic review of the literature.

    PubMed

    Kaster, Tyler S; Yaremko, Brian; Palma, David A; Rodrigues, George B

    2015-03-01

    To identify survival and toxicity characteristics associated with radical-intent hypofractionated radiotherapy for the treatment of stage III non-small-cell lung cancer (NSCLC). Relevant studies were identified from a systematic PubMed search of articles published between January 1990 and January 2014. All studies were peer reviewed and included both retrospective and prospective studies of NSCLC patients being treated with radical hypofractionated radiotherapy. Data on overall survival (OS) and toxicity were extracted from each of the studies where available. Of 685 studies initially identified by the search, a total of 33 studies were found to be relevant and were included in this systematic review. The number of fractions ranged from 15 to 35, the dose per fraction ranged from 2.3 to 3.5 Gy, and the delivered dose ranged from 45.0 to 85.5 Gy. Fifteen of the studies included concurrent chemotherapy, while 18 did not. OS was found to be associated with tumor biological effective dose, with the Pearson correlation coefficient ranging from 0.34 to 0.48. For both concurrent and nonconcurrent chemoradiotherapy acute pulmonary, late esophageal and late pulmonary incidences of toxicity ranged from 1.2% to 12.2%, but had 95% confidence intervals that included zero. The greatest incidence of toxicity was acute esophageal toxicity at 14.9% (95% confidence interval, 0.7%, 29.1%). There is a moderate linear relationship between biological effective dose and OS, and greater acute esophageal toxicity with concurrent chemotherapy. Improving outcomes in stage III NSCLC may involve some form of hypofractionation in the context of systemic concurrent therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Hypofractionated conformal irradiation of patients with malignant glioma.

    PubMed

    Aboziada, Mohamed A; Abo-Kresha, Ahmed E

    2012-09-01

    The aim of the study is to evaluate the effect of a conformal irradiation in short fractionation scheme of 49.5Gy in 15 fractions in an overall time of 3 weeks, in terms of overall survival (OAS) and progression free survival (PFS) rates in brain glioma patients. A prospective study was conducted on 54 brain glioma patients and was carried out in the Radiation Oncology Department, South Egypt Cancer Institute, Assiut University during the period from April 2006 till June 2009. Patients were treated by hypofractionated conformal irradiation (49.5 Gy/15 fractions/3 weeks). The median follow up was 23 months (range: 9-39 months). Two-year OAS and PFS rates were 68% and 60%, respectively. In univariate analysis, age >50 years, poor performance status [Karnofasky score of ≥40-≤70%], poor neuroperformance status of score III, high-grade tumor [glioblastoma multiforme], and biopsy were all associated with statistically significant reduction in OAS and PFS rates. Multivariate analysis, showed that age >50 years and glioblastoma pathology were the only independent prognostic factors that were associated with poor OAS (p=0.003 and p=0.004, respectively), and PFS (p=0.027 and p=0.011, respectively). Hypofractionated conformal radiotherapy was as effective as the conventional radiotherapy, with time sparing for patients, and for radiation oncology centers. Hypofractionated radiotherapy may be considered the radiotherapy regimen of choice in clinical practice for patients with gliomas. Copyright © 2012. Published by Elsevier B.V.

  4. Definitive hypofractionated radiotherapy for early glottic carcinoma: experience of 55Gy in 20 fractions.

    PubMed

    Ermiş, Ekin; Teo, Mark; Dyker, Karen E; Fosker, Chris; Sen, Mehmet; Prestwich, Robin Jd

    2015-09-23

    A wide variety of fractionation schedules have been employed for the treatment of early glottic cancer. The aim is to report our 10-year experience of using hypofractionated radiotherapy with 55Gy in 20 fractions at 2.75Gy per fraction. Patients treated between 2004 and 2013 with definitive radiotherapy to a dose of 55Gy in 20 fractions over 4 weeks for T1/2 N0 squamous cell carcinoma of the glottis were retrospectively identified. Patients with prior therapeutic minor surgery (eg. laser stripping, cordotomy) were included. The probabilities of local control, ultimate local control (including salvage surgery), regional control, cause specific survival (CSS) and overall survival (OS) were calculated. One hundred thirty-two patients were identified. Median age was 65 years (range 33-89). Median follow up was 72 months (range 7-124). 50 (38 %), 18 (14 %) and 64 (48 %) of patients had T1a, T1b and T2 disease respectively. Five year local control and ultimate local control rates were: overall - 85.6 % and 97.3 % respectively, T1a - 91.8 % and 100 %, T1b - 81.6 and 93.8 %, and T2 - 80.9 % and 95.8 %. Five year regional control, CSS and OS rates were 95.4 %, 95.7 % and 78.8 % respectively. There were no significant associations of covariates (e.g. T-stage, extent of laryngeal extension, histological grade) with local control on univariate analysis. Only increasing age and transglottic extension in T2 disease were significantly associated with overall survival (both p <0.01). Second primary cancers developed in 17 % of patients. 13 (9.8 %) of patients required enteral tube feeding support during radiotherapy; no patients required long term enteral nutrition. One patient required a tracheostomy due to a non-functioning larynx on long term follow up. Hypofractionated radiation therapy with a dose of 55Gy in 20 fractions for early stage glottic cancer provides high rates of local control with acceptable toxicity.

  5. Hypofractionated Palliative Radiotherapy with Concurrent Radiosensitizing Chemotherapy for Advanced Head and Neck Cancer Using the "QUAD-SHOT Regimen".

    PubMed

    Gamez, Mauricio E; Agarwal, Manuj; Hu, Kenneth S; Lukens, John N; Harrison, Louis B

    2017-02-01

    To analyze the outcomes using the hypofractionated palliative radiotherapy regimen "QUAD-Shot" with concurrent radiosensitizing chemotherapy for advanced head and neck cancer. We analyzed twenty-one patients with newly-diagnosed or recurrent head and neck cancer treated with palliative hypofractionated concurrent chemoradiation using the QUAD-Shot regimen. All patients received at least one cycle of RT, with sixteen patients (76%) completing all three cycles. 85.7 % of patients had objective response to therapy with five patients (23.8%) demonstrating complete response (CR) and thirteen patients (61.9%) demonstrating partial response (PR). Palliation of symptoms was achieved in all (100%) of the sixteen patients that completed the three cycles. Median overall survival and median progression-free survival were 7 and 4 months, respectively. QUAD-Shot palliative radiation therapy coupled with radiosensitizing chemotherapy is efficacious and well-tolerated in patients with newly-diagnosed or recurrent head and neck cancer not amenable to curative therapy. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  6. Under-reported dosimetry errors due to interplay effects during VMAT dose delivery in extreme hypofractionated stereotactic radiotherapy.

    PubMed

    Gauer, Tobias; Sothmann, Thilo; Blanck, Oliver; Petersen, Cordula; Werner, René

    2018-06-01

    Radiotherapy of extracranial metastases changed from normofractioned 3D CRT to extreme hypofractionated stereotactic treatment using VMAT beam techniques. Random interaction between tumour motion and dynamically changing beam parameters might result in underdosage of the CTV even for an appropriately dimensioned ITV (interplay effect). This study presents a clinical scenario of extreme hypofractionated stereotactic treatment and analyses the impact of interplay effects on CTV dose coverage. For a thoracic/abdominal phantom with an integrated high-resolution detector array placed on a 4D motion platform, dual-arc treatment plans with homogenous target coverage were created using a common VMAT technique and delivered in a single fraction. CTV underdosage through interplay effects was investigated by comparing dose measurements with and without tumour motion during plan delivery. Our study agrees with previous works that pointed out insignificant interplay effects on target coverage for very regular tumour motion patterns like simple sinusoidal motion. However, we identified and illustrated scenarios that are likely to result in a clinically relevant CTV underdosage. For tumour motion with abnormal variability, target coverage quantified by the CTV area receiving more than 98% of the prescribed dose decreased to 78% compared to 100% at static dose measurement. This study is further proof of considerable influence of interplay effects on VMAT dose delivery in stereotactic radiotherapy. For selected conditions of an exemplary scenario, interplay effects and related motion-induced target underdosage primarily occurred in tumour motion pattern with increased motion variability and VMAT plan delivery using complex MLC dose modulation.

  7. Hypofractionated stereotactic photon radiotherapy of posteriorly located choroidal melanoma with five fractions at ten Gy--clinical results after six years of experience.

    PubMed

    Dunavoelgyi, Roman; Zehetmayer, Martin; Gleiss, Andreas; Geitzenauer, Wolfgang; Kircher, Karl; Georg, Dietmar; Schmidt-Erfurth, Ursula; Poetter, Richard; Dieckmann, Karin

    2013-08-01

    To evaluate long-term safety and efficacy of hypofractionated stereotactic photon radiotherapy with 5 five fractions at 10 Gy each in patients with centrally located choroidal melanoma. Ninety-one patients with centrally located choroidal melanoma were treated stereotactically at a linear accelerator with 6 MV photon beams with 5 fractions at 10 Gy each. Examinations were performed at baseline and every 3 months in the first 2 years, then every 6 months until 5 years and yearly thereafter. Median follow-up was 37.8 months (IQR 19.2-49.9). They included visual acuity assessment, routine ophthalmological examinations with fundoscopy, echography for measurement of tumor dimensions, medical examinations and, if necessary, fluorescein angiography. Initial tumor base diameters, height and volume were 11.20mm (IQR 9.10-13.70), 9.80 mm (IQR 7.80-11.70), 4.53 mm (IQR 3.33-6.43) and 253.8mm(3) (IQR 127.5-477.0). Local tumor control and eye retention rates were 97.7% and 86.4% after 5 years, respectively. Eight patients developed metastatic disease and 3 of them died due to metastatic disease during the follow-up period. Median visual acuity decreased from 0.67 initially to 0.05 at the last individual follow-up (p<0.001). The most common toxicities (any grade) were radiation retinopathy (n=39), optic neuropathy (n=32), radiogenic cataract (n=21), neovascular glaucoma (n=15) and dry eye syndrome (n=10). The 5 year probabilities to remain free of these side effects (any grade) were 26.0%, 45.4%, 55.4%, 72.6% and 80.5%, respectively. The most important prognostic factors for toxicities were the largest tumor base diameter, tumor height and tumor distance to the optic disk. Hypofractionated stereotactic photon radiotherapy with a total dose of 50 Gy delivered in 5 fractions is a highly effective treatment option in patients with centrally located choroidal melanoma and has a moderate toxicity profile. Copyright © 2013. Published by Elsevier Ireland Ltd.

  8. COX-2 expression and outcome in canine nasal carcinomas treated with hypofractionated radiotherapy.

    PubMed

    Belshaw, Z; Constantio-Casas, F; Brearley, M J; Dunning, M D; Holmes, M A; Dobson, J M

    2011-06-01

    The expression of cyclooxygenase isoform 2 (COX-2) in canine nasal carcinomas has been well documented. COX-2 expression has proven to be a prognostic factor in several human tumours. The aims of this study were to assess the correlation between immunohistochemical COX-2 expression and prognosis using rhinoscopic biopsies from 42 dogs with nasal carcinomas treated with hypofractionated radiotherapy, and to establish a replicable COX-2 scoring system. Ninety per cent of sections evaluated were COX-2 positive with a mean score of 6.6 (median 8.0; range 0-12). Neither COX-2 expression nor tumour type had a significant correlation with survival. There are likely to be many as yet unidentified variants which contribute to length of survival in dogs with nasal carcinomas. Immunohistochemical COX-2 expression appears unlikely to be of prognostic significance for canine nasal carcinoma. © 2010 Blackwell Publishing Ltd.

  9. Hypofractionated Whole-Brain Radiotherapy for Multiple Brain Metastases From Transitional Cell Carcinoma of the Bladder

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rades, Dirk, E-mail: Rades.Dirk@gmx.ne; Department of Radiation Oncology, University of Hamburg; Meyners, Thekla

    2010-10-01

    Purpose: Brain metastases in bladder cancer patients are extremely rare. Most patients with multiple lesions receive longer-course whole-brain radiotherapy (WBRT) with 10 x 3 Gy/2 weeks or 20 x 2 Gy/4 weeks. Because its radiosensitivity is relatively low, metastases from bladder cancer may be treated better with hypofractionated radiotherapy. This study compared short-course hypofractionated WBRT (5 x 4 Gy/1 week) to longer-course WBRT. Methods and Materials: Data for 33 patients receiving WBRT alone for multiple brain metastases from transitional cell bladder carcinoma were retrospectively analyzed. Short-course WBRT with 5 x 4 Gy (n = 12 patients) was compared to longer-coursemore » WBRT with 10 x 3 Gy/20 x 2 Gy (n = 21 patients) for overall survival (OS) and local (intracerebral) control (LC). Five additional potential prognostic factors were investigated: age, gender, Karnofsky performance score (KPS), number of brain metastases, and extracranial metastases. The Bonferroni correction for multiple tests was used to adjust the p values derived from the multivariate analysis. p values of <0.025 were considered significant. Results: At 6 months, OS was 42% after 5 x 4 Gy and 24% after 10 x 3/20 x 2 Gy (p = 0.31). On univariate analysis, improved OS was associated with less than four brain metastases (p = 0.021) and almost associated with a lack of extracranial metastases (p = 0.057). On multivariate analysis, both factors were not significant. At 6 months, LC was 83% after 5 x 4 Gy and 27% after 10 x 3/20 x 2 Gy (p = 0.035). Improved LC was almost associated with a KPS of {>=}70 (p = 0.051). On multivariate analysis, WBRT regimen was almost significant (p = 0.036). KPS showed a trend (p = 0.07). Conclusions: Short-course WBRT with 5 x 4 Gy should be seriously considered for most patients with multiple brain metastases from bladder cancer, as it resulted in improved LC.« less

  10. Different rectal toxicity tolerance with and without simultaneous conventionally-fractionated pelvic lymph node treatment in patients receiving hypofractionated prostate radiotherapy.

    PubMed

    McDonald, Andrew M; Baker, Christopher B; Popple, Richard A; Shekar, Kiran; Yang, Eddy S; Jacob, Rojymon; Cardan, Rex; Kim, Robert Y; Fiveash, John B

    2014-06-03

    To investigate added morbidity associated with the addition of pelvic elective nodal irradiation (ENI) to hypofractionated radiotherapy to the prostate. Two-hundred twelve patients, treated with hypofractionated radiotherapy to the prostate between 2004 and 2011, met the inclusion criteria for the analysis. All patients received 70 Gy to the prostate delivered over 28 fractions and 103 (49%) received ENI consisting of 50.4 Gy to the pelvic lymphatics delivered simultaneously in 1.8 Gy fractions. The mean dose-volume histograms were compared between the two subgroups defined by use of ENI, and various dose-volume parameters were analyzed for effect on late lower gastrointestinal (GI) and genitourinary (GU) toxicity. Acute grade 2 lower GI toxicity occurred in 38 (37%) patients receiving ENI versus 19 (17%) in those who did not (p = 0.001). The Kaplan-Meier estimate of grade ≥ 2 lower GI toxicity at 3 years was 15.3% for patients receiving ENI versus 5.3% for those who did not (p = 0.026). Each rectal isodose volume was increased for patients receiving ENI up to 50 Gy (p ≤ 0.021 for each 5 Gy increment). Across all patients, the absolute V70 of the rectum was the only predictor of late GI toxicity. When subgroups, defined by the use of ENI, were analyzed separately, rectal V70 was only predictive of late GI toxicity for patients who received ENI. For patients receiving ENI, V70 > 3 cc was associated with an increased risk of late GI events. Elective nodal irradiation increases the rates of acute and late GI toxicity when delivered simultaneously with hypofractioanted prostate radiotherapy. The use of ENI appears to sensitize the rectum to hot spots, therefore we recommend added caution to minimize the volume of rectum receiving 100% of the prescription dose in these patients.

  11. Long-term mortality from cardiac causes after adjuvant hypofractionated vs. conventional radiotherapy for localized left-sided breast cancer.

    PubMed

    Chan, Elisa K; Woods, Ryan; Virani, Sean; Speers, Caroline; Wai, Elaine S; Nichol, Alan; McBride, Mary L; Tyldesley, Scott

    2015-01-01

    Ongoing concern remains regarding cardiac injury with hypofractionated whole breast/chest-wall radiotherapy (HF-WBI) compared to conventional radiotherapy (CF-WBI) in left-sided breast cancer patients. The purpose was to determine if cardiac mortality increases with HF-WBI relative to CF-WBI. Between 1990 and 1998, 5334 women with early-stage breast cancer received post-operative radiotherapy to the breast/chest wall alone. A population-based database recorded baseline patient, tumor and treatment factors. Baseline cardiovascular risk factors were identified from hospital administrative records. A propensity-score model balanced risk factors between radiotherapy groups. Cause of death was coded as breast cancer, cardiac or other cause. Cumulative mortality from each cause after radiotherapy was estimated using a competing risk approach. For left-sided cases, median follow-up was 14.2 years. 485 women received CF-WBI, 2221 women received HF-WBI. There was no difference in 15-year mortality from cardiac causes: 4.8% with HF-WBI and 4.2% with CF-WBI (p=0.74), even after propensity-score adjustment (p=0.45). There was no difference in breast cancer mortality or other cause mortality. For right-sided cases, there was no difference in mortality for the three causes of death. At 15-years follow-up, cardiac mortality is not statistically different among left-sided breast cancer patients treated with HF-WBI or CF-WBI. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Different rectal toxicity tolerance with and without simultaneous conventionally-fractionated pelvic lymph node treatment in patients receiving hypofractionated prostate radiotherapy

    PubMed Central

    2014-01-01

    Purpose To investigate added morbidity associated with the addition of pelvic elective nodal irradiation (ENI) to hypofractionated radiotherapy to the prostate. Methods and materials Two-hundred twelve patients, treated with hypofractionated radiotherapy to the prostate between 2004 and 2011, met the inclusion criteria for the analysis. All patients received 70 Gy to the prostate delivered over 28 fractions and 103 (49%) received ENI consisting of 50.4 Gy to the pelvic lymphatics delivered simultaneously in 1.8 Gy fractions. The mean dose-volume histograms were compared between the two subgroups defined by use of ENI, and various dose-volume parameters were analyzed for effect on late lower gastrointestinal (GI) and genitourinary (GU) toxicity. Results Acute grade 2 lower GI toxicity occurred in 38 (37%) patients receiving ENI versus 19 (17%) in those who did not (p = 0.001). The Kaplan-Meier estimate of grade ≥ 2 lower GI toxicity at 3 years was 15.3% for patients receiving ENI versus 5.3% for those who did not (p = 0.026). Each rectal isodose volume was increased for patients receiving ENI up to 50 Gy (p ≤ 0.021 for each 5 Gy increment). Across all patients, the absolute V70 of the rectum was the only predictor of late GI toxicity. When subgroups, defined by the use of ENI, were analyzed separately, rectal V70 was only predictive of late GI toxicity for patients who received ENI. For patients receiving ENI, V70 > 3 cc was associated with an increased risk of late GI events. Conclusions Elective nodal irradiation increases the rates of acute and late GI toxicity when delivered simultaneously with hypofractioanted prostate radiotherapy. The use of ENI appears to sensitize the rectum to hot spots, therefore we recommend added caution to minimize the volume of rectum receiving 100% of the prescription dose in these patients. PMID:24893842

  13. Hypofractionated stereotactic radiotherapy combined with topotecan in recurrent malignant glioma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wurm, Reinhard E.; Kuczer, David A.; Schlenger, Lorenz

    Purpose: To assess hypofractionated stereotactic radiotherapy (H-SRT) with concurrent topotecan in patients with recurrent malignant glioma. Methods and Materials: Between February 1998 and December 2001, 25 patients with recurrent malignant glioma were treated in a phase I-II study (8 females and 17 males; median age, 45 years; range, 11-66 years; median Karnofsky performance status, 80%, range, 50-100%; median Mini Mental Standard Examination score, 25 points; range, 10-30 points). Of the 25 patients, 20% had World Health Organization Grade III and 80% World Health Organization Grade IV glioma. All patients had been treated previously by external beam radiotherapy with 54.4 Gymore » in 34 fractions twice daily, at least 6 h apart, within 3.5 weeks or 60 Gy in 30 fractions within 6 weeks. In addition, 84% had already received at least one chemotherapy regimen for recurrence. The median H-SRT dose at the 80% isodose was 25 Gy, and the maximal dose was 30 Gy delivered in five to six fractions on consecutive days. Topotecan (1.1 mg/m{sup 2}/d) was given as a continuous i.v. infusion during H-SRT. Depending on the toxicity and compliance, patients received an additional 48 topotecan courses. Results: For all patients, the actuarial median progression-free survival was 10.5 months (range, 1.4-47.8 months), the median functional survival was 12.6 months (range, 1.6-49.5 months), and the median overall survival was 14.5 months (range, 3-56.4 months). Twelve percent of patients developed presumed adverse radiation effects (Radiation Therapy Oncology Group Grade 2). According to the Common Toxicity Criteria, version 2.0, no topotecan-related Grade 4 toxicity was noted. Grade 3 neutropenia was documented after 14 and Grade 3 thrombopenia after 12 courses. Conclusion: H-SRT with topotecan is feasible and well-tolerated in patients with recurrent high-grade glioma and results in similar survival compared with other repeat treatment modalities.« less

  14. A Phase I Study of Hypofractionated Carbon-ion Radiotherapy for Stage III Non-small Cell Lung Cancer.

    PubMed

    Saitoh, Jun-Ichi; Shirai, Katsuyuki; Abe, Takanori; Kubo, Nobuteru; Ebara, Takeshi; Ohno, Tatsuya; Minato, Koichi; Saito, Ryusei; Yamada, Masanobu; Nakano, Takashi

    2018-02-01

    The aim of this study was to assess the feasibility and safety of hypofractionated carbon-ion radiotherapy (C-ion RT) in patients with stage III non-small cell lung cancer (NSCLC). Patients with untreated, histologically proven, unresectable stage III NSCLC and not candidates for chemotherapy were included in this study. C-ion RT was planned and administered with 4 Gy (relative biological effectiveness (RBE)) in daily fractions for a total dose of 64 Gy (RBE) without combined chemotherapy. Dose-limiting toxicity (DLT) was defined as suspension of C-ion RT treatment for 2 weeks due to ≥ grade 2 pneumonitis, or any other ≥ grade 3 adverse event, or as any ≥ grade 4 adverse event within 3 months from the start of treatment. Six patients were treated between June 2013 and December 2014. The planned full dose of C-ion RT (64 Gy (RBE)) was completed in all patients. No patient developed DLT, and no patient experienced toxicities of ≥grade 3 severity. The overall response rate was 100%, and local tumor control was achieved in all patients during the survival period. Hypofractionated C-ion RT of patients with stage III NSCLC was feasible and well tolerated. Although the number of patients in this study was small, the results support further investigations to confirm the long-term therapeutic efficacy of this treatment. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  15. Acute toxicity and its dosimetric correlates for high-risk prostate cancer treated with moderately hypofractionated radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arunsingh, Moses; Mallick, Indranil, E-mail: imallick@gmail.com; Prasath, Sriram

    Aims: To report the acute toxicity and the dosimetric correlates after moderately hypofractionated radiotherapy for localized prostate cancer. Methods: A total of 101 patients with localized prostate cancer were treated with image-guided intensity-modulated radiation therapy. Patients were treated to 65 Gy/25 Fr/5 weeks (n = 18), or 60 Gy/20 Fr/4 weeks (n = 83). Most (82.2%) had high-risk or pelvic node-positive disease. Acute toxicity was assessed using Radiation Therapy Oncology Group (RTOG) acute morbidity scoring criteria. Dose thresholds for acute rectal and bladder toxicity were identified. Results: The incidence of acute grade 2 GI toxicity was 20.8%, and grade 2more » genitourinary (GU) toxicity was 6.9%. No Grade 3 to 4 toxicity occurred. Small bowel toxicity was uncommon (Gr 2 = 4%). The 2 Gy equivalent doses (EQD2) to the rectum and bladder (α/β = 3) calculated showed that the absolute doses were more consistent predictors of acute toxicities than the relative volumes. Those with grade 2 or more GI symptoms had significantly higher V{sub EQD2-60} {sub Gy} (13.2 vs 9.9 cc, p = 0.007) and V{sub EQD2-50} {sub Gy} (20.6 vs 15.4 cc, p = 0.005). Those with grade 2 or more GU symptoms had significantly higher V{sub EQD2-70} {sub Gy} (30.4 vs 18.4 cc, p = 0.001) and V{sub EQD2-65} {sub Gy} (44.0 vs 28.8 cc, p = 0.001). The optimal cutoff value for predicting grade 2 acute proctitis, for V{sub EQD2-60} {sub Gy} was 9.7 cc and for V{sub EQD2-50} {sub Gy} was 15.9 cc. For grade 2 GU symptoms, the threshold values were 23.6 cc for V{sub EQD2-70} {sub Gy} and 38.1 cc for V{sub EQD2-65} {sub Gy}. Conclusions: Hypofractionated radiotherapy for prostate cancer is well tolerated and associated with manageable acute side effects. The absolute dose-volume parameters of rectum and bladder predict for acute toxicities.« less

  16. Hypofractionated accelerated CT-guided interstitial ¹⁹²Ir-HDR-Brachytherapy as re-irradiation in inoperable recurrent cervical lymphadenopathy from head and neck cancer.

    PubMed

    Tselis, Nikolaos; Ratka, Markus; Vogt, Hans-Georg; Kolotas, Christos; Baghi, Mehran; Baltas, Dimos; Fountzilas, George; Georgoulias, Vassilios; Ackermann, Hanns; Zamboglou, Nikolaos

    2011-01-01

    Despite significant improvements in the treatment of head and neck cancer (HNC), lymph node recurrences remain a clinical challenge after primary radiotherapy. The value of interstitial (IRT) brachytherapy (BRT) for control of lymph node recurrence remains unclear. In order to clarify its role a retrospective review was undertaken on the value of computed tomography (CT)-guided IRT high-dose-rate (HDR)-BRT in isolated recurrent disease from HNC. From 2000 to 2007, 74 patients were treated for inoperable recurrent cervical lymphadenopathy. All patients had previously been treated with radical radiotherapy or chemoradiation with or without surgery. The HDR-BRT delivered a median salvage dose of 30.0 Gy (range, 12.0-36.0 Gy) in twice-daily fractions of 2.0-5.0 Gy in 71 patients and of 30.0 Gy (range, 10.0-36.0 Gy) in once-daily fractions of 6.0-10.0 Gy in three patients. The overall and disease-free survival rates at one, two and three years were 42%, 19%, 6%, and 42%, 37% and 19%, respectively. The local control probability at one, two and three years was 67% at all three time points. Grade III-IV complications occurred in 13% of patients. In patients with inoperable recurrent neck disease from HNC, hypofractionated accelerated CT-guided IRT-HDR-BRT can play an important role in providing palliation and tumor control. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  17. Moderately hypofractionated conformal radiation treatment of thoracic esophageal carcinoma.

    PubMed

    Ma, Jin-Bo; Wei, Lin; Chen, Er-Cheng; Qin, Guang; Song, Yi-Peng; Chen, Xiang-Ming; Hao, Chuan-Guo

    2012-01-01

    To prospectively assess the efficacy and safety of moderately hypofractionated conformal radiotherapy in patients with thoracic esophageal cancer. From Sept. 2002 to Oct. 2005, 150 eligible patients with T2-4N0-1M0 stage thoracic esophageal squamous cell cancers were enrolled to receive either conventional fractionated radiation (CFR) or moderately hypofractionated radiation (MHR) with a three- dimensional conformal radiation technique. Of the total, 74 received moderately hypofractionated radiation with total dose of 54-60 Gy/18-20 fractions for 3.5-4 weeks in the MHR arm, and 76 received conventional radiation with total dose of 60 Gy/30 fractions for 6 weeks in the CFR arm. Concurrent chemotherapy comprised of paclitaxel and cisplatin. Safety was evaluated, and local control and overall survival rates were calculated. Statistically significant differences between the CFR versus MHR arms were observed in local/regional failure rate (47.3% v 27.0%, P=0.034) and the percentage of patients with persistent local disease (26.3% v 10.8%, P=0.012). But 3 and 5-year overall survival rates (43.2%, 38.8% v 38.2%, 28.0%, respectively) were not different between the two arms (P=0.268). There were no significant differences in the incidences of grade 3 or higher acute toxicities (66.3% v 50.0%) and late complications rates (27.0% v 22.4%) between the MHR and CFR arms. Moderately hypofractionated, three-dimensional radiation treatment could improve the local control rate of esophageal cancer and potentially increase patient survival.

  18. [Hypofractionated whole breast irradiation (WBRT): Results and indications].

    PubMed

    Cutuli, B

    2016-10-01

    Breast irradiation after breast-conserving surgery is essential for maximizing local control and overall survival. The increase of breast cancer (BC) incidence, constraints of classical five weeks (w) radiation regimens and scarcity of radiotherapy units have led to test short hypofractionated WBRT schemes. One pilot study and three prospective randomized trials have tested various hypofractionated regimens of WBRT. About 7000 patients were included and follow-up ranged from 5 to 12 years. The conclusion of these trials is similar, showing local control and toxicity equivalent to these of the standard regimens. Three schemes are now clearly validated: 42.5Gy/16fr/3w, 40Gy/15fr/3w, or 42Gy/13fr/5w. However, the majority of included patients had favorable prognostic factors, were treated to the breast only and the boost dose, when indicated, was delivered with a standard fractionation. Therefore, we recommend the regimens preferentially in patients treated to the breast only, and without nodal involvement. These studies did not evaluate the addition of a boost dose with a hypofractionated scheme. If a boost is to be given, a standard fractionation should be used. Particular care should be taken to avoid heterogeneities leading to high fraction doses to organs at risk (lung and heart). Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  19. WE-F-304-00: Outcomes of Hypofractionated Treatments - Results of the WGSBRT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe andmore » effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear

  20. WE-F-304-03: Optic Nerve/Chiasm Hypofractionated SRS/SRT Dose Tolerance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Milano, M.

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe andmore » effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear

  1. Hypofractionated Radiation Therapy for Breast Ductal Carcinoma In Situ

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hathout, Lara; Hijal, Tarek; Théberge, Valérie

    2013-12-01

    Purpose: Conventional radiation therapy (RT) administered in 25 fractions after breast-conserving surgery (BCS) is the standard treatment for ductal carcinoma in situ (DCIS) of the breast. Although accelerated hypofractionated regimens in 16 fractions have been shown to be equivalent to conventional RT for invasive breast cancer, few studies have reported results of using hypofractionated RT in DCIS. Methods and Materials: In this multicenter collaborative effort, we retrospectively reviewed the records of all women with DCIS at 3 institutions treated with BCS followed by hypofractionated whole-breast RT (WBRT) delivered in 16 fractions. Results: Between 2003 and 2010, 440 patients with DCISmore » underwent BCS followed by hypofractionated WBRT in 16 fractions for a total dose of 42.5 Gy (2.66 Gy per fraction). Boost RT to the surgical bed was given to 125 patients (28%) at a median dose of 10 Gy in 4 fractions (2.5 Gy per fraction). After a median follow-up time of 4.4 years, 14 patients had an ipsilateral local relapse, resulting in a local recurrence-free survival of 97% at 5 years. Positive surgical margins, high nuclear grade, age less than 50 years, and a premenopausal status were all statistically associated with an increased occurrence of local recurrence. Tumor hormone receptor status, use of adjuvant hormonal therapy, and administration of additional boost RT did not have an impact on local control in our cohort. On multivariate analysis, positive margins, premenopausal status, and nuclear grade 3 tumors had a statistically significant worse local control rate. Conclusions: Hypofractionated RT using 42.5 Gy in 16 fractions provides excellent local control for patients with DCIS undergoing BCS.« less

  2. Sci—Thur AM: YIS - 02: Radiogenomic Modeling of Normal Tissue Toxicities in Prostate Cancer Patients Receiving Hypofractionated Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Coates, J; Jeyaseelan, K; Ybarra, N

    2014-08-15

    Inter-patient radiation sensitivity variability has recently been shown to have a genetic component. This genetic component may play a key role in explaining the fluctuating rates of radiation-induced toxicities (RITs). Single nucleotide polymorphisms (SNPs) have thus far yielded inconsistent results in delineating RITs while copy number variations (CNVs) have not yet been investigated for such purposes. We explore a radiogenomic modeling approach to investigate the association of CNVs and SNPs, along with clinical and dosimetric variables, in radiation induced rectal bleeding (RB) and erectile dysfunction (ED) in prostate cancer patients treated with curative hypofractionated irradiation. A cohort of 62 prostatemore » cancer patients who underwent hypofractionated radiotherapy (66 Gy in 22 fractions) between 2002 to 2010 were retrospectively genotyped for CNV and SNP rs5489 in the xrcc1 DNA repair gene. Late toxicity rates for RB grade 2 and 3 and grade 3 alone were 29.0% and 12.9%, respectively. ED toxicity was found to be 62.9%. Radiogenomic model performance was evaluated using receiver operating characteristic area under the curve (AUC) and resampling by cross-validation. Binary variables were evaluated using Chi-squared contingency table analysis and multivariate models by Spearman's rank correlation coefficient (rs). Ten patients were found to have three copies of xrcc1 CNV (RB: χ{sup 2}=14.6, p<0.001 and ED: χ{sup 2}=4.88, p=0.0272) and twelve had heterozygous rs25489 SNP (RB: χ{sup 2}=0.278, p=0.599 and ED: χ{sup 2}=0.112, p=0.732). Radiogenomic modeling yielded significant, cross-validated NTCP models for RB (AUC=0.665) and ED (AUC=0.754). These results indicate that CNVs may be potential predictive biomarkers of both late ED and RB.« less

  3. Hypofractionated Proton Boost Combined with External Beam Radiotherapy for Treatment of Localized Prostate Cancer

    PubMed Central

    Johansson, Silvia; Åström, Lennart; Sandin, Fredrik; Isacsson, Ulf; Montelius, Anders; Turesson, Ingela

    2012-01-01

    Proton boost of 20 Gy in daily 5 Gy fractions followed by external beam radiotherapy (EBRT) of 50 Gy in daily 2 Gy fractions were given to 278 patients with prostate cancer with T1b to T4N0M0 disease. Fifty-three percent of the patients received neoadjuvant androgen deprivation therapy (N-ADT). The medium followup was 57 months. The 5-year PSA progression-free survival was 100%, 95%, and 74% for low-, intermediate-, and high-risk patients, respectively. The toxicity evaluation was supported by a patient-reported questionnaire before every consultant visit. Cumulative probability and actuarial prevalence of genitourinary (GU) and gastrointestinal (GI) toxicities are presented according to the RTOG classification. N-ADT did not influence curability. Mild pretreatment GU-symptoms were found to be a strong predictive factor for GU-toxicity attributable to treatment. The actuarial prevalence declined over 3 to 5 years for both GU and GI toxicities, indicating slow resolution of epithelial damage to the genitourinary and gastrointestinal tract. Bladder toxicities rather than gastrointestinal toxicities seem to be dose limiting. More than 5-year followup is necessary to reveal any sign of true progressive late side effects of the given treatment. Hypofractionated proton-boost combined with EBRT is associated with excellent curability of localized PC and acceptable frequencies of treatment toxicity. PMID:22848840

  4. Hypofractionated Stereotactic Radiotherapy in Five Daily Fractions for Post-Operative Surgical Cavities in Brain Metastases Patients with and without Prior Whole Brain Radiation

    PubMed Central

    Al-Omair, Ameen; Soliman, Hany; Xu, Wei; Karotki, Aliaksandr; Mainprize, Todd; Phan, Nicolas; Das, Sunit; Keith, Julia; Yeung, Robert; Perry, James; Tsao, May; Sahgal, Arjun

    2013-01-01

    Our purpose was to report efficacy of hypofractionated cavity stereotactic radiotherapy (HCSRT) in patients with and without prior whole brain radiotherapy (WBRT). 32 surgical cavities in 30 patients (20 patients/21 cavities had no prior WBRT and 10 patients/11 cavities had prior WBRT) were treated with image-guided linac stereotactic radiotherapy. 7 of the 10 prior WBRT patients had “resistant” local disease given prior surgery, post-operative WBRT and a re-operation, followed by salvage HCSRT. The clinical target volume was the post-surgical cavity, and a 2-mm margin applied as planning target volume. The median total dose was 30 Gy (range: 25-37.5 Gy) in 5 fractions. In the no prior and prior WBRT cohorts, the median follow-up was 9.7 months (range: 3.0-23.6) and 15.3 months (range: 2.9-39.7), the median survival was 23.6 months and 39.7 months, and the 1-year cavity local recurrence progression-free survival (LRFS) was 79 and 100%, respectively. At 18 months the LRFS dropped to 29% in the prior WBRT cohort. Grade 3 radiation necrosis occurred in 3 prior WBRT patients. We report favorable outcomes with HCSRT, and well selected patients with prior WBRT and “resistant” disease may have an extended survival favoring aggressive salvage HCSRT at a moderate risk of radiation necrosis. PMID:23617283

  5. Hypofractionated stereotactic radiotherapy in five daily fractions for post-operative surgical cavities in brain metastases patients with and without prior whole brain radiation.

    PubMed

    Al-Omair, Ameen; Soliman, Hany; Xu, Wei; Karotki, Aliaksandr; Mainprize, Todd; Phan, Nicolas; Das, Sunit; Keith, Julia; Yeung, Robert; Perry, James; Tsao, May; Sahgal, Arjun

    2013-12-01

    Our purpose was to report efficacy of hypofractionated cavity stereotactic radiotherapy (HCSRT) in patients with and without prior whole brain radiotherapy (WBRT). 32 surgical cavities in 30 patients (20 patients/21 cavities had no prior WBRT and 10 patients/11 cavities had prior WBRT) were treated with image-guided linac stereotactic radiotherapy. 7 of the 10 prior WBRT patients had "resistant" local disease given prior surgery, post-operative WBRT and a re-operation, followed by salvage HCSRT. The clinical target volume was the post-surgical cavity, and a 2-mm margin applied as planning target volume. The median total dose was 30 Gy (range: 25-37.5 Gy) in 5 fractions. In the no prior and prior WBRT cohorts, the median follow-up was 9.7 months (range: 3.0-23.6) and 15.3 months (range: 2.9-39.7), the median survival was 23.6 months and 39.7 months, and the 1-year cavity local recurrence progression- free survival (LRFS) was 79 and 100%, respectively. At 18 months the LRFS dropped to 29% in the prior WBRT cohort. Grade 3 radiation necrosis occurred in 3 prior WBRT patients. We report favorable outcomes with HCSRT, and well selected patients with prior WBRT and "resistant" disease may have an extended survival favoring aggressive salvage HCSRT at a moderate risk of radiation necrosis.

  6. Clinical experience with image-guided radiotherapy in an accelerated partial breast intensity-modulated radiotherapy protocol.

    PubMed

    Leonard, Charles E; Tallhamer, Michael; Johnson, Tim; Hunter, Kari; Howell, Kathryn; Kercher, Jane; Widener, Jodi; Kaske, Terese; Paul, Devchand; Sedlacek, Scot; Carter, Dennis L

    2010-02-01

    To explore the feasibility of fiducial markers for the use of image-guided radiotherapy (IGRT) in an accelerated partial breast intensity modulated radiotherapy protocol. Nineteen patients consented to an institutional review board approved protocol of accelerated partial breast intensity-modulated radiotherapy with fiducial marker placement and treatment with IGRT. Patients (1 patient with bilateral breast cancer; 20 total breasts) underwent ultrasound guided implantation of three 1.2- x 3-mm gold markers placed around the surgical cavity. For each patient, table shifts (inferior/superior, right/left lateral, and anterior/posterior) and minimum, maximum, mean error with standard deviation were recorded for each of the 10 BID treatments. The dose contribution of daily orthogonal films was also examined. All IGRT patients underwent successful marker placement. In all, 200 IGRT treatment sessions were performed. The average vector displacement was 4 mm (range, 2-7 mm). The average superior/inferior shift was 2 mm (range, 0-5 mm), the average lateral shift was 2 mm (range, 1-4 mm), and the average anterior/posterior shift was 3 mm (range, 1 5 mm). This study shows that the use of IGRT can be successfully used in an accelerated partial breast intensity-modulated radiotherapy protocol. The authors believe that this technique has increased daily treatment accuracy and permitted reduction in the margin added to the clinical target volume to form the planning target volume. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Volumetric Modulated Arc-Based Hypofractionated Stereotactic Radiotherapy for the Treatment of Selected Intracranial Arteriovenous Malformations: Dosimetric Report and Early Clinical Experience

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Subramanian, Sai; Srinivas, Chilukuri; Ramalingam, K.

    2012-03-01

    Purpose: To evaluate, with a dosimetric and clinical feasibility study, RapidArc (a volumetric modulated arc technique) for hypofractionated stereotactic radiotherapy treatment of large arteriovenous malformations (AVMs). Methods and Materials: Nine patients were subject to multimodality imaging (magnetic resonance, computed tomography, and digital subtraction angiography) to determine nidus and target volumes, as well as involved organs at risk (optical structures, inner ear, brain stem). Plans for multiple intensity-modulated arcs with a single isocenter were optimized for a fractionation of 25 Gy in 5 fractions. All plans were optimized for 6-MV photon beams. Dose-volume histograms were analyzed to assess plan quality. Deliverymore » parameters were reported to appraise technical features of RapidArc, and pretreatment quality assurance measurements were carried out to report on quality of delivery. Results: Average size of AVM nidus was 26.2 cm{sup 3}, and RapidArc plans provided complete target coverage with minimal overdosage (V{sub 100%} = 100% and V{sub 110%} < 1%) and excellent homogeneity (<6%). Organs at risk were highly spared. The D{sub 1%} to chiasm, eyes, lenses, optic nerves, and brainstem (mean {+-} SD) was 6.4 {+-} 8.3, 1.9 {+-} 3.8, 2.3 {+-} 2.2, 0.7 {+-} 0.9, 4.4 {+-} 7.2, 12.2 {+-} 9.6 Gy, respectively. Conformity index (CI{sub 95%}) was 2.2 {+-} 0.1. The number of monitor units per gray was 277 {+-} 45, total beam-on time was 2.5 {+-} 0.3 min. Planning vs. delivery {gamma} pass rate was 98.3% {+-} 0.9%. None of the patients developed acute toxicity. With a median follow-up of 9 months, 3 patients presented with deterioration of symptoms and were found to have postradiation changes but responded symptomatically to steroids. These patients continue to do well on follow-up. One patient developed headache and seizures, which was attributed to intracranial bleed, confirmed on imaging. Conclusion: Hypofractionated stereotactic radiotherapy can be

  8. Transformation of Physical DVHs to Radiobiologically Equivalent Ones in Hypofractionated Radiotherapy Analyzing Dosimetric and Clinical Parameters: A Practical Approach for Routine Clinical Practice in Radiation Oncology

    PubMed Central

    Thrapsanioti, Zoi; Karanasiou, Irene; Platoni, Kalliopi; Efstathopoulos, Efstathios P.; Matsopoulos, George; Dilvoi, Maria; Patatoukas, George; Chaldeopoulos, Demetrios; Kelekis, Nikolaos; Kouloulias, Vassilis

    2013-01-01

    Purpose. The purpose of this study was to transform DVHs from physical to radiobiological ones as well as to evaluate their reliability by correlations of dosimetric and clinical parameters for 50 patients with prostate cancer and 50 patients with breast cancer, who were submitted to Hypofractionated Radiotherapy. Methods and Materials. To achieve this transformation, we used both the linear-quadratic model (LQ model) and the Niemierko model. The outcome of radiobiological DVHs was correlated with acute toxicity score according to EORTC/RTOG criteria. Results. Concerning the prostate radiotherapy, there was a significant correlation between RTOG acute rectal toxicity and D 50 (P < 0.001) and V 60 (P = 0.001) dosimetric parameters, calculated for α/β = 10 Gy. Moreover, concerning the breast radiotherapy there was a significant correlation between RTOG skin toxicity and V ≥60 dosimetric parameter, calculated for both α/β = 2.3 Gy (P < 0.001) and α/β = 10 Gy (P < 0.001). The new tool seems reliable and user-friendly. Conclusions. Our proposed model seems user-friendly. Its reliability in terms of agreement with the presented acute radiation induced toxicity was satisfactory. However, more patients are needed to extract safe conclusions. PMID:24348743

  9. A phase 1 dose-escalation study of the oral histone deacetylase inhibitor abexinostat in combination with standard hypofractionated radiotherapy in advanced solid tumors

    PubMed Central

    Deutsch, Eric; Moyal, Elizabeth Cohen-Jonathan; Gregorc, Vanesa; Zucali, Paolo Andrea; Menard, Jean; Soria, Jean-Charles; Kloos, Ioana; Hsu, Jeff; Luan, Ying; Liu, Emily; Vezan, Remus; Graef, Thorsten; Rivera, Sofia

    2017-01-01

    Current treatments for advanced solid tumors tend to be only palliative. Although radiotherapy is administered with a curative intent, radioresistance and dose-limiting toxicities pose limitations to treatment. Abexinostat, an oral pan-histone deacetylase inhibitor, demonstrated enhanced sensitivity to radiation in various solid tumor cell lines. We conducted an exploratory, phase 1, dose-escalation study of abexinostat in combination with standard hypofractionated radiotherapy in patients with advanced solid tumors treated in a palliative setting. Among 58 treated patients, the median age was 61.5 years (range, 20-82); 47% of the patients had M1 stage disease, and 95% had received previous chemotherapy alone or chemotherapy in combination with surgery and/or radiotherapy. The recommended phase 2 dose was determined to be 90 mg/m2 (140 mg). Of the 51 patients evaluable for response, best overall response was 8% (1 complete response [CR], 3 partial responses [PRs]), and best loco-regional response was 12% (1 CR and 5 PRs) at a median follow-up of 16 weeks. Of note, patients with target or non-target brain lesions showed encouraging responses, with 1 patient achieving a best loco-regional response of CR. Treatment-emergent grade ≥3 adverse events (AEs) were few, with most common being thrombocytopenia (17%), lymphopenia (12%), and hypokalemia (7%). Six patients (10%) discontinued treatment due to AEs. No grade ≥3 prolongation of the QTc interval was observed, with no treatment discontinuations due to this AE. Oral abexinostat combined with radiotherapy was well tolerated in patients with advanced solid tumors. The combination may have potential for treatment of patients with brain lesions. PMID:28915584

  10. WE-FG-BRA-03: Oxygen Interplay in Hypofractionated Radiotherapy: A Hidden Opportunity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kissick, M; Campos, D; Desai, V

    2016-06-15

    Purpose: Local oxygen during a radiotherapy fraction has been shown to change over a full range of the oxygen enhancement ratio (OER) during the same time scale as the treatment fraction. Interplay with local oxygen is then likely a concern, especially for hypofractionation. Our experiments that show a strong role for metabolic dynamics suggesting one could manipulate this interplay for more efficacious treatments. Methods: Two published experiments are presented with the same human head and neck cancer cell line (UM-SCC-22B). One is a cell-specific in vitro prompt response to a 10 Gy dose of orthovotage radiation using fluorescence lifetime imagingmore » (FLIM), benchmarked with a Seahorse assay. The other in vivo study uses autocorrelation analysis with blood oxygen level dependent magnetic resonance imaging (MRI-BOLD) on xenografts. In vivo results are verified with diffuse optics using spectra fitting and photoacoustic measurements. All these measurements are at high time resolution: sampling is one per minute. Results: Interplay happens when the radiosensitivity modulates at the same time scale as the radiation. These results show dynamics at these time scales. 1. The dominant time scale of the acute hypoxia in cell line xenografts is shown to be on the order of minutes to tens of minutes: similar to a metabolic oscillation known as the ‘glycolytic oscillator.’ 2. The radiation dose itself alters metabolism within minutes to tens of minutes also. Conclusion: These results vary with cell type. There is a possibility that special timing and dose levels could be used for radiation. Gating could be used for maximal oxygen during treatment. There is an analogy to the interplay discussions with tumor motion, except that an oxygen interplay could more likely be patient-specific at a more fundamental level.« less

  11. Revised Modelling of the Addition of Synchronous Chemotherapy to Radiotherapy in Squamous Cell Carcinoma of the Head and Neck-A Low α/β?

    PubMed

    Best, James; Fong, Charles; Benghiat, Helen; Mehanna, Hisham; Glaholm, John; Hartley, Andrew

    2018-06-13

    Background: The effect of synchronous chemotherapy in squamous cell carcinoma of the head and neck (SCCHN) has been modelled as additional Biologically Effective Dose (BED) or as a prolonged tumour cell turnover time during accelerated repopulation. Such models may not accurately predict the local control seen when hypofractionated accelerated radiotherapy is used with synchronous chemotherapy. Methods: For the purposes of this study three isoeffect relationships were assumed: Firstly, from the RTOG 0129 trial, synchronous cisplatin chemotherapy with 70 Gy in 35 fractions over 46 days results in equivalent local control to synchronous cisplatin chemotherapy with 36 Gy in 18# followed by 36 Gy in 24# (2# per day) over a total of 39 days. Secondly, in line with primary local control outcomes from the PET-Neck study, synchronous cisplatin chemotherapy with 70 Gy in 35# over 46 days results in equivalent local control to synchronous cisplatin chemotherapy delivered with 65 Gy in 30# over 39 days. Thirdly, from meta-analysis data, 70 Gy in 35# over 46 days with synchronous cisplatin results in equivalent local control to 84 Gy in 70# over 46 days delivered without synchronous chemotherapy. Using the linear quadratic equation the above isoeffect relationships were expressed algebraically to determine values of α , α/β , and k for SCCHN when treated with synchronous cisplatin using standard parameters for the radiotherapy alone schedule ( α = 0.3 Gy −1 , α/β = 10 Gy, and k = 0.42 Gy 10 day −1 ). Results: The values derived for α/β , α and k were 2 Gy, 0.20 and 0.21 Gy −1 , and 0.65 and 0.71 Gy₂day −1 . Conclusions: Within the limitations of the assumptions made, this model suggests that accelerated repopulation may remain a significant factor when synchronous chemotherapy is delivered with radiotherapy in SCCHN. The finding of a low α/β for SCCHN treated with cisplatin suggests a

  12. Hypofractionated Volumetric Modulated Arc Radiotherapy with simultaneous Elective Nodal Irradiation is feasible in prostate cancer patients: A single institution experience.

    PubMed

    Hegazy, Mohamed W; Mahmood, Rana I; Al Otaibi, Mohammed F; Khalil, Ehab M

    2016-06-01

    To assess feasibility, toxicity and biochemical relapse-free survival (b-RFS) for a group of organ confined (OC) Saudi prostate cancer patients treated by hypo-fractionated Volumetric Modulated Arc Radiation Therapy (VMAT) Simultaneous Integrated Boost (SIB) Elective Nodal Irradiation (ENI) whole pelvic radiotherapy (WPRT). Between March 2009 and January 2014, 29 OC prostate cancer patients; median age 64years, PS 0-1 were treated in King Faisal Specialist Hospital - Riyadh, Kingdom of Saudi Arabia using VMAT-SIB-ENI-WPRT, to a total dose of 70Gy in 28 fractions. Twenty Four patients (83%) were treated with neo-adjuvant; concurrent androgen deprivation therapy (ADT). Median follow-up (FU) was 42months (range: 18-72months). The 3-year actuarial b-RFS for low/intermediate and high risk groups were 100%, and 48%, respectively (p=0.09) with a median FU period of 34months (range: 14-53months). Gleason Score (p=0.02), and pretreatment PSA (p=0.01) were predictive for biochemical failure on univariate analysis; with no observed prostate cancer-related deaths. Grade 2 acute/late GI and GU toxicities were 28%/0% and 17%/10% respectively with no reported grade 3/4 toxicities. Four (50%) out of the 8 patients with baseline partial potency, retained sexual function on long term follow-up. Hypo-fractionation dose escalation VMAT-SIB-ENI-WPRT using 2 arcs is a feasible technique for intermediate/high risk OC prostate cancer patients, with acceptable rates of acute/late toxicities, much favorable planning target volume (PTV) coverage, and shorter overall treatment time. Prospective randomized controlled trials are encouraged to confirm its equivalence to other fractionation schemes. Copyright © 2016 National Cancer Institute, Cairo University. Production and hosting by Elsevier B.V. All rights reserved.

  13. A Phase I Dose Escalation Study of Hypofractionated IMRT Field-in-Field Boost for Newly Diagnosed Glioblastoma Multiforme

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Monjazeb, Arta M., E-mail: arta.monjazeb@ucdmc.ucdavis.edu; Ayala, Deandra; Jensen, Courtney

    2012-02-01

    Objectives: To describe the results of a Phase I dose escalation trial for newly diagnosed glioblastoma multiforme (GBM) using a hypofractionated concurrent intensity-modulated radiotherapy (IMRT) boost. Methods: Twenty-one patients were enrolled between April 1999 and August 2003. Radiotherapy consisted of daily fractions of 1.8 Gy with a concurrent boost of 0.7 Gy (total 2.5 Gy daily) to a total dose of 70, 75, or 80 Gy. Concurrent chemotherapy was not permitted. Seven patients were enrolled at each dose and dose limiting toxicities were defined as irreversible Grade 3 or any Grade 4-5 acute neurotoxicity attributable to radiotherapy. Results: All patientsmore » experienced Grade 1 or 2 acute toxicities. Acutely, 8 patients experienced Grade 3 and 1 patient experienced Grade 3 and 4 toxicities. Of these, only two reversible cases of otitis media were attributable to radiotherapy. No dose-limiting toxicities were encountered. Only 2 patients experienced Grade 3 delayed toxicity and there was no delayed Grade 4 toxicity. Eleven patients requiring repeat resection or biopsy were found to have viable tumor and radiation changes with no cases of radionecrosis alone. Median overall and progression-free survival for this cohort were 13.6 and 6.5 months, respectively. One- and 2-year survival rates were 57% and 19%. At recurrence, 15 patients received chemotherapy, 9 underwent resection, and 5 received radiotherapy. Conclusions: Using a hypofractionated concurrent IMRT boost, we were able to safely treat patients to 80 Gy without any dose-limiting toxicity. Given that local failure still remains the predominant pattern for GBM patients, a trial of dose escalation with IMRT and temozolomide is warranted.« less

  14. Choosing Wisely? Patterns and Correlates of the Use of Hypofractionated Whole-Breast Radiation Therapy in the State of Michigan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jagsi, Reshma, E-mail: rjagsi@med.umich.edu; Griffith, Kent A.; Heimburger, David

    Purpose: Given evidence from randomized trials that have established the non-inferiority of more convenient and less costly courses of hypofractionated radiotherapy to the whole breast in selected breast cancer patients who receive lumpectomy, we sought to investigate the use of hypofractionated radiation therapy and factors associated with its use in a consortium of radiation oncology practices in Michigan. We sought to determine the extent to which variation in use occurs at the physician or practice level versus the extent to which use reflects individualization based on potentially relevant patient characteristics (such as habitus, age, chemotherapy receipt, or laterality). Methods andmore » Materials: We evaluated associations between receipt of hypofractionated radiation therapy and various patient, provider, and practice characteristics in a multilevel model. Results: Of 1477 patients who received lumpectomy and whole-breast radiation therapy and were registered by the Michigan Radiation Oncology Quality Consortium (MROQC) from October 2011 to December 2013, 913 had T1-2, N0 breast cancer. Of these 913, 283 (31%) received hypofractionated radiation therapy. Among the 13 practices, hypofractionated radiation therapy use ranged from 2% to 80%. On multilevel analysis, 51% of the variation in the rate of hypofractionation was attributable to the practice level, 21% to the provider level, and 28% to the patient level. On multivariable analysis, hypofractionation was more likely in patients who were older (odds ratio [OR] 2.16 for age ≥50 years, P=.007), less likely in those with larger body habitus (OR 0.52 if separation between tangent entry and exit ≥25 cm, P=.002), and more likely without chemotherapy receipt (OR 3.82, P<.001). Hypofractionation use was not higher in the last 6 months analyzed: 79 of 252 (31%) from June 2013 to December 2013 and 204 of 661 (31%) from October 2011 to May 2013 (P=.9). Conclusions: Hypofractionated regimens of whole

  15. SU-E-T-776: Use of Quality Metrics for a New Hypo-Fractionated Pre-Surgical Mesothelioma Protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richardson, S; Mehta, V

    Purpose: The “SMART” (Surgery for Mesothelioma After Radiation Therapy) approach involves hypo-fractionated radiotherapy of the lung pleura to 25Gy over 5 days followed by surgical resection within 7. Early clinical results suggest that this approach is very promising, but also logistically challenging due to the multidisciplinary involvement. Due to the compressed schedule, high dose, and shortened planning time, the delivery of the planned doses were monitored for safety with quality metric software. Methods: Hypo-fractionated IMRT treatment plans were developed for all patients and exported to Quality Reports™ software. Plan quality metrics or PQMs™ were created to calculate an objective scoringmore » function for each plan. This allows for an objective assessment of the quality of the plan and a benchmark for plan improvement for subsequent patients. The priorities of various components were incorporated based on similar hypo-fractionated protocols such as lung SBRT treatments. Results: Five patients have been treated at our institution using this approach. The plans were developed, QA performed, and ready within 5 days of simulation. Plan Quality metrics utilized in scoring included doses to OAR and target coverage. All patients tolerated treatment well and proceeded to surgery as scheduled. Reported toxicity included grade 1 nausea (n=1), grade 1 esophagitis (n=1), grade 2 fatigue (n=3). One patient had recurrent fluid accumulation following surgery. No patients experienced any pulmonary toxicity prior to surgery. Conclusion: An accelerated course of pre-operative high dose radiation for mesothelioma is an innovative and promising new protocol. Without historical data, one must proceed cautiously and monitor the data carefully. The development of quality metrics and scoring functions for these treatments allows us to benchmark our plans and monitor improvement. If subsequent toxicities occur, these will be easy to investigate and incorporate into

  16. [Clinical experience of carbon ion radiotherapy for malignant tumors].

    PubMed

    Ishikawa, Hitoshi; Tsuji, Hiroshi; Tsujii, Hirohiko

    2006-04-01

    The carbon ion (C-ion) beams provide unique advantageous biological and physical properties in radiotherapy (RT) for malignant tumors. C-ion beams have a high relative biological effectiveness (RBE) resulting from the high linear energy transfer (LET). In terms of their physical characteristics, C-ion beams exhibit a spread-out Bragg peak (SOBP) and make for a better dose distribution of the target volume by specified beam modulations. Between June 1994 and August 2005, a total of 2,371 patients with malignant tumors were registered in phase I/II dose-escalation studies and clinical phase II trials using C-ion beams generated at Heavy Ion Medical Accelerator in Chiba (HIMAC). In the initial dose-escalation studies, grade 3 or more late rectal complications had developed in some patients. However, the adverse effects were resolved because of the use of appropriate dose levels and modification of the radiation technique. C-ion beams can carry out hypofractionated radiotherapy with a large fraction dose and reduce the overall treatment times compared with conventional radiotherapy. They can also achieve better local tumor control even for radio-resistant tumors such as malignant melanoma, hepatocellular carcinoma and bone and soft tissue sarcomas with minimal morbidity to the normal surrounding tissues.

  17. Post-radiotherapy hypothyroidism in dogs treated for thyroid carcinomas.

    PubMed

    Amores-Fuster, I; Cripps, P; Blackwood, L

    2017-03-01

    Hypothyroidism is a common adverse event after head and neck radiotherapy in human medicine, but uncommonly reported in canine patients. Records of 21 dogs with histologically or cytologically confirmed thyroid carcinoma receiving definitive or hypofractionated radiotherapy were reviewed. Nine cases received 48 Gy in 12 fractions, 10 received 36 Gy in 4 fractions and 2 received 32 Gy in 4 fractions. Seventeen cases had radiotherapy in a post-operative setting. Ten cases developed hypothyroidism (47.6%) after radiotherapy. The development of hypothyroidism was not associated with the radiotherapy protocol used. Median time to diagnosis of hypothyroidism was 6 months (range, 1-13 months). Hypothyroidism is a common side effect following radiotherapy for thyroid carcinomas. Monitoring of thyroid function following radiotherapy is recommended. No specific risk factors have been identified. © 2015 John Wiley & Sons Ltd.

  18. Phantom-to-clinic development of hypofractionated stereotactic body radiotherapy for early-stage glottic laryngeal cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ding, Chuxiong; Chun, Stephen G.; Sumer, Baran D.

    The purpose of this study was to commission and clinically test a robotic stereotactic delivery system (CyberKnife, Sunnyvale, CA) to treat early-stage glottic laryngeal cancer. We enrolled 15 patients with cTis-T2N0M0 carcinoma of the glottic larynx onto an institutional review board (IRB)-approved clinical trial. Stereotactic body radiotherapy (SBRT) plans prescribed 45 Gy/10 fractions to the involved hemilarynx. SBRT dosimetry was compared with (1) standard carotid-sparing laryngeal intensity-modulated radiation therapy (IMRT) and (2) selective hemilaryngeal IMRT. Our results demonstrate that SBRT plans improved sparing of the contralateral arytenoid (mean 20.0 Gy reduction, p <0.001), ipsilateral carotid D{sub max} (mean 20.6 Gy reduction, p <0.001), contralateral carotidmore » D{sub max} (mean 28.1 Gy reduction, p <0.001), and thyroid D{sub mean} (mean 15.0 Gy reduction, p <0.001) relative to carotid-sparing IMRT. SBRT also modestly improved dose sparing to the contralateral arytenoid (mean 4.8 Gy reduction, p = 0.13) and spinal cord D{sub max} (mean 4.9 Gy reduction, p = 0.015) relative to selective hemilaryngeal IMRT plans. This “phantom-to-clinic” feasibility study confirmed that hypofractionated SBRT treatment for early-stage laryngeal cancer can potentially spare dose to adjacent normal tissues relative to current IMRT standards. Clinical efficacy and toxicity correlates continue to be collected through an ongoing prospective trial.« less

  19. Phase I/II study of hypofractioned radiation with three-dimensional conformal radiotherapy for clinical T3-4N0-1M0 stage esophageal carcinoma.

    PubMed

    Song, Y-P; Ma, J-B; Hu, L-K; Zhou, W; Chen, E-C; Zhang, W

    2011-02-01

    Compared to conventional fractionated-dose radiotherapy, high hypofractionated-dose radiotherapy could yield tumoricidal effects. However, few clinical trials of hypofractionated radiotherapy in loco-regionally advanced incurable esophageal cancer at present have yet been performed. The purpose of the current study was to evaluate the efficacy and toxicity of hypofractioned radiation with three-dimensional conformal radiotherapy for clinical T3-4N0-1M0 stage esophageal carcinoma. From September 2003 to December 2005, 45 patients with locally advanced esophageal carcinoma were grouped and received three-dimensional conformal hypofractioned radiotherapy (3D-CRT) whose fractionated dose was gradually increase per group. Radiotherapy was administered to a total dose of from 50 to 54 Gy (fractionated dose of from 3.0 to 6.0 Gy, 3 times weekly), over a 3-4 week period. And patients received 4 cycles chemotherapy. The median follow-up period for survivors was 38 months. Treatment tolerance rate was 78.8% with daily dose of from 3 to 5 Gy. There are 21.2% patients occurring Grade ≥ 3 acute toxicities. But patients couldn't tolerate daily dose of 6 Gy (55.6%). The 1-year, 2-year and 3-year local control rates were 62%, 49% and 39% respectively. And the 1-year, 2-year and 3-year overall survival rates were 34%, 21% and 9% respectively. The median overall survival time was 17 months. At the time of following up, 13 patients (31.0%) had occurred esophageal late complications, with mainly esophageal perforation, hemorrhage or stenosis, including initial stenosis aggravation. Therefore hypofractionated irradiation was thought to be feasible for clinical T3-4N0-1M0 stage esophageal carcinoma. And daily dose of ≤5 Gy was comparatively suitable in hypofractionated irradiation for esophageal carcinoma, and the patients tolerated well. But further research was in need also.

  20. Use of hydrogel spacer for improved rectal dose-sparing in patients undergoing radical radiotherapy for localized prostate cancer: First Canadian experience

    PubMed Central

    Berlin, Alejandro; Di Tomasso, Anne; Ballantyne, Heather; Patterson, Susan; Lam, Tony; Sundaramurthy, Aravind; Helou, Joelle; Bayley, Andrew; Chung, Peter

    2017-01-01

    We describe the initial experience using a hydrogel spacer (SpaceOAR) to separate the prostate-rectum interspace in patients planned to undergo radical hypofractionated, image-guided, intensity-modulated radiotherapy (IG-IMRT). We depict and discuss the impact of SpaceOAR in the context of hypofractionated IG-IMRT, and the particular considerations for its applications in the Canadian setting. PMID:29257741

  1. Hypofractionated Image-guided Radiation Therapy (3Gy/fraction) in Patients Affected by Inoperable Advanced-stage Non-small Cell Lung Cancer After Long-term Follow-up.

    PubMed

    Agolli, Linda; Valeriani, Maurizio; Bracci, Stefano; Nicosia, Luca; DE Sanctis, Vitaliana; Enrici, Riccardo Maurizi; Osti, Mattia Falchetto

    2015-10-01

    We conducted long-term follow-up analysis of the outcomes for patients affected by advanced-stage non-small cell lung cancer (NSCLC) treated with hypofractionated radiotherapy (RT). Sixty patients with advanced-stage NSCLC (IIIA-IV) treated with hypofractionated radiotherapy (60Gy/20 fractions) were analyzed. Radiation was delivered using an image-guided RT technique to verify the correct position. Toxicities were graded according to the Common Toxicity Criteria for Adverse Effects v4.0 scale. Overall, six patients achieved a complete response and 46 patients had a partial response (tumor response rate 86%). After a median follow-up of 30 months, locoregional progression occurred in 23 patients and distant progression occurred in 38. The 1-year and 2-years overall survival were 57% and 40%, respectively. The 1-year and 2-years progression-free survival (PFS) were 47.1% and 33.5%, respectively. The median duration of OS and PFS was 13 months and 12 months, respectively. The 2-year local PFS and metastases-free survival (MFS) were 53% and 40.3%, respectively. On univariate analysis, the T-size (≥5 cm), and type of response to RT (non-response/progressive disease) were significantly associated with worse OS. Type of response was identified as significant prognostic factors for PFS (p<0.01) local PFS (p=0.015) and MFS (p<0.01). Acute grade 3 esophagitis and pneumonitis occurred in three patients (5%) and four patients (6%), respectively. Late grade 3 esophagitis and pneumonitis occurred in 2% (one patient) and 3% (two patients), respectively. No patient experienced grade 4 acute or late RT-related toxicities. Hypofractionated RT offers good disease control for patients with advanced-stage NSCLC with acceptable toxicity rates. Phase III randomized trials are necessary to compare hypofractionated RT with conventional RT. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  2. A neutron track etch detector for electron linear accelerators in radiotherapy

    PubMed Central

    Vukovic, Branko; Faj, Dario; Poje, Marina; Varga, Maja; Radolic, Vanja; Miklavcic, Igor; Ivkovic, Ana; Planinic, Josip

    2010-01-01

    Background Electron linear accelerators in medical radiotherapy have replaced cobalt and caesium sources of radiation. However, medical accelerators with photon energies over 10 MeV generate undesired fast neutron contamination in a therapeutic X-ray photon beam. Photons with energies above 10 MeV can interact with the atomic nucleus of a high-Z material, of which the target and the head of an accelerator consist, and lead to the neutron ejection. Results and conclusions. Our neutron dosimeter, composed of the LR-115 track etch detector and boron foil BN-1 converter, was calibrated on thermal neutrons generated in the nuclear reactor of the Josef Stefan Institute (Slovenia), and applied to dosimetry of undesirable neutrons in photon radiotherapy by the linear accelerator 15 MV Siemens Mevatron. Having considered a high dependence of a cross-section between neutron and boron on neutron energy, and broad neutron spectrum in a photon beam, as well as outside the entrance door to maze of the Mevatron, we developed a method for determining the effective neutron detector response. A neutron dose rate in the photon beam was measured to be 1.96 Sv/h. Outside the Mevatron room the neutron dose rate was 0.62 μSv/h. PACS: 87.52. Ga; 87.53.St; 29.40.Wk. PMID:22933893

  3. Stereotactic radiosurgery versus stereotactic radiotherapy for patients with vestibular schwannoma: a Leksell Gamma Knife Society 2000 debate.

    PubMed

    Linskey, M E

    2000-12-01

    By definition, the term "radiosurgery" refers to the delivery of a therapeutic radiation dose in a single fraction, not simply the use of stereotaxy. Multiple-fraction delivery is better termed "stereotactic radiotherapy." There are compelling radiobiological principles supporting the biological superiority of single-fraction radiation for achieving an optimal therapeutic response for the slowly proliferating, late-responding, tissue of a schwannoma. It is axiomatic that complication avoidance requires precise three-dimensional conformality between treatment and tumor volumes. This degree of conformality can only be achieved through complex multiisocenter planning. Alternative radiosurgery devices are generally limited to delivering one to four isocenters in a single treatment session. Although they can reproduce dose plans similar in conformality to early gamma knife dose plans by using a similar number of isocenters, they cannot reproduce the conformality of modern gamma knife plans based on magnetic resonance image-targeted localization and five to 30 isocenters. A disturbing trend is developing in which institutions without nongamma knife radiosurgery (GKS) centers are championing and/or shifting to hypofractionated stereotactic radiotherapy for vestibular schwannomas. This trend appears to be driven by a desire to reduce complication rates to compete with modern GKS results by using complex multiisocenter planning. Aggressive advertising and marketing from some of these centers even paradoxically suggests biological superiority of hypofractionation approaches over single-dose radiosurgery for vestibular schwannomas. At the same time these centers continue to use the term radiosurgery to describe their hypofractionated radiotherapy approach in an apparent effort to benefit from a GKS "halo effect." It must be reemphasized that as neurosurgeons our primary duty is to achieve permanent tumor control for our patients and not to eliminate complications at the

  4. Stereotactic radiosurgery versus stereotactic radiotherapy for patients with vestibular schwannoma: a Leksell Gamma Knife Society 2000 debate.

    PubMed

    Linskey, Mark E

    2013-12-01

    By definition, the term "radiosurgery" refers to the delivery of a therapeutic radiation dose in a single fraction, not simply the use of stereotaxy. Multiple-fraction delivery is better termed "stereotactic radiotherapy." There are compelling radiobiological principles supporting the biological superiority of single-fraction radiation for achieving an optimal therapeutic response for the slowly proliferating, late-responding, tissue of a schwannoma. It is axiomatic that complication avoidance requires precise three-dimensional conformality between treatment and tumor volumes. This degree of conformality can only be achieved through complex multiisocenter planning. Alternative radiosurgery devices are generally limited to delivering one to four isocenters in a single treatment session. Although they can reproduce dose plans similar in conformality to early gamma knife dose plans by using a similar number of isocenters, they cannot reproduce the conformality of modern gamma knife plans based on magnetic resonance image--targeted localization and five to 30 isocenters. A disturbing trend is developing in which institutions without nongamma knife radiosurgery (GKS) centers are championing and/or shifting to hypofractionated stereotactic radiotherapy for vestibular schwannomas. This trend appears to be driven by a desire to reduce complication rates to compete with modern GKS results by using complex multiisocenter planning. Aggressive advertising and marketing from some of these centers even paradoxically suggests biological superiority of hypofractionation approaches over single-dose radiosurgery for vestibular schwannomas. At the same time these centers continue to use the term radiosurgery to describe their hypofractionated radiotherapy approach in an apparent effort to benefit from a GKS "halo effect." It must be reemphasized that as neurosurgeons our primary duty is to achieve permanent tumor control for our patients and not to eliminate complications at the

  5. Projected Improvements in Accelerated Partial Breast Irradiation Using a Novel Breast Stereotactic Radiotherapy Device: A Dosimetric Analysis.

    PubMed

    Snider, James W; Mutaf, Yildirim; Nichols, Elizabeth; Hall, Andrea; Vadnais, Patrick; Regine, William F; Feigenberg, Steven J

    2017-01-01

    Accelerated partial breast irradiation has caused higher than expected rates of poor cosmesis. At our institution, a novel breast stereotactic radiotherapy device has demonstrated dosimetric distributions similar to those in brachytherapy. This study analyzed comparative dose distributions achieved with the device and intensity-modulated radiation therapy accelerated partial breast irradiation. Nine patients underwent computed tomography simulation in the prone position using device-specific immobilization on an institutional review board-approved protocol. Accelerated partial breast irradiation target volumes (planning target volume_10mm) were created per the National Surgical Adjuvant Breast and Bowel Project B-39 protocol. Additional breast stereotactic radiotherapy volumes using smaller margins (planning target volume_3mm) were created based on improved immobilization. Intensity-modulated radiation therapy and breast stereotactic radiotherapy accelerated partial breast irradiation plans were separately generated for appropriate volumes. Plans were evaluated based on established dosimetric surrogates of poor cosmetic outcomes. Wilcoxon rank sum tests were utilized to contrast volumes of critical structures receiving a percentage of total dose ( Vx). The breast stereotactic radiotherapy device consistently reduced dose to all normal structures with equivalent target coverage. The ipsilateral breast V20-100 was significantly reduced ( P < .05) using planning target volume_10mm, with substantial further reductions when targeting planning target volume_3mm. Doses to the chest wall, ipsilateral lung, and breast skin were also significantly lessened. The breast stereotactic radiotherapy device's uniform dosimetric improvements over intensity-modulated accelerated partial breast irradiation in this series indicate a potential to improve outcomes. Clinical trials investigating this benefit have begun accrual.

  6. Breast-Conserving Treatment in the Elderly: Long-Term Results of Adjuvant Hypofractionated and Normofractionated Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kirova, Youlia M.; Campana, Francois; Savignoni, Alexia

    2009-09-01

    Purpose: To evaluate the long-term cause-specific survival (CSS), locoregional recurrence-free survival (LRFS), and metastases-free survival (MFS) in elderly breast cancer patients receiving adjuvant normofractionated (NF) or hypofractionated (HF) radiotherapy (RT). Methods and Materials: Between 1995 and 1999, 367 women aged {>=}70 years with nonmetastatic Stage T1 or T2 tumors were treated by breast-conserving surgery and adjuvant RT at the Institut Curie. They underwent wide tumor excision with or without lymph node dissection followed by RT. They received either a NF-RT schedule, which delivered a total dose of 50 Gy (25 fractions, 5 fractions weekly) to the whole breast, followed bymore » a boost to the tumor bed when indicated, or a HF-RT schedule, which delivered a total dose of 32.5 Gy (five fractions of 6.5 Gy, once weekly) with no subsequent boost. The HF-RT schedule was indicated for the more elderly patients. Results: A total of 317 patients were in the NF-RT group, with 50 in the HF-RT group. The median follow-up was 93 months (range, 9-140). The 5- and 7-year CSS, LRFS, and MFS rates were similar in both groups. The 5-year NF-RT and HF-RT rate was 96% and 95% for CSS, 95% and 94% for LRFS, and 94% and 95% for MFS, respectively. The 7-year NF-RT and HF-RT rate was 93% and 87% for CSS, 93% and 91% for LRFS, and 92% and 93% for MFS, respectively. Conclusion: According to the findings from this retrospective study, the HF-RT schedule is an acceptable alternative to NF-RT for elderly patients. However, large-scale prospective randomized trials are needed to confirm these results.« less

  7. External-beam Co-60 radiotherapy for canine nasal tumors: a comparison of survival by treatment protocol.

    PubMed

    Yoon, J H; Feeney, D A; Jessen, C R; Walter, P A

    2008-02-01

    A retrospective analysis of survival times in dogs with intranasal tumors was performed comparing those treated using hypofractionated or full course Co-60 radiotherapy protocols alone or with surgical adjuvant therapy and those receiving no radiation treatment. One hundred thirty-nine dogs presented to the University of Minnesota Veterinary Medical Center for treatment of histologically-confirmed nasal neoplasia between July 1983 and October 2001 met the criteria for review. Statistically analyzed parameters included age at diagnosis, tumor histologic classification, fractionation schedule (number of treatments, and number of treatment days/week) (classified as hypofractionated if 2 or less treatments/week); calculated minimum tumor dose/fraction; calculated total minimum tumor dose (classified as hypofractionated if less than 37 Gy in six or fewer fractions); number of radiotherapy portals, a treatment gap of more than 7 days in a full course (3-5 treatments/week, 3-3.5 week treatment time) radiotherapy protocol, the influence of eye shields on survival following single portal DV fields, the survey radiographic extent of the disease, and the presence or absence of cytoreductive surgery. There was a significant relationship only between protocols using 3 or more treatments/week and at least 37 Gy cumulative minimum tumor dose and survival. However, there was no significant relationship between either total minimum tumor dose or dose/fraction and survival and there were no significant relationships between survival and any of the other variables analyzed including tumor histologic type.

  8. Hypofractionation for Prostate Cancer

    PubMed Central

    Ritter, Mark; Forman, Jeffrey; Kupelian, Patrick; Lawton, Colleen; Petereit, Daniel

    2011-01-01

    Hypofractionation for prostate cancer was originally carried out in the pursuit of efficiency and convenience, but has now attracted greatly renewed interest based upon a hypothesis that prostate cancers have a higher sensitivity to fraction size, reflected in a low α/β ratio, then do late responding organs at risk such as the rectum or bladder. Tumor control and acceptable toxicity outcomes from several hypofractionation or brachytherapy analyses do in fact support an α/β ratio for prostate cancer that is low, perhaps even lower that that for the normal organs that ordinarily constrain the delivery of radiation therapy. However, many of these studies lack sufficient patient numbers and follow-up, are clouded by dose inhomogeneity issues in the case of brachytherapy, or delivered effective doses that were too low by contemporary standards. Thus, the clinical efficacy of the approach has yet to be fully validated. However, a number of newer prospective trials, some randomized, are underway or have reached accrual await sufficient follow-up for analysis. These studies, which cover a wide range of doses per fraction, should ultimately be capable of validating the utility of prostate hypofractionation and the models that predict its effects. With hypofractionation’s significant potential for therapeutic gain, cost savings and improved patient convenience, the future management of localized prostate cancer could be profoundly altered in the process. PMID:19197165

  9. Hypofractionated radiation therapy for prostate cancer: biologic and technical considerations

    PubMed Central

    Sanfilippo, Nicholas J; Cooper, Benjamin T

    2014-01-01

    The optimal radiation schedule for the curative treatment of prostate cancer is not known. The dose-response of tumors and normal tissues to fractionated irradiation can be described according to a parameter called the alpha-beta ratio (α/β). In the past several years numerous reports have been published that suggest that the alpha-beta ratio for prostate cancer may be quite low; between 1 and 3. If this hypothesis is true, then a radiation therapy schedule that employs less frequent and larger fractions, termed hypofractionation, may be more efficacious. Multiple randomized trials have been conducted comparing moderate (less than 5 Gy/day) hypofractionated radiation therapy and standard radiation therapy in men with prostate cancer. In the majority of these studies the moderate hypofractionated arm had equivalent efficacy with a similar or improved side effect profile. One area to use caution may be in patients with compromised (IPSS > 12) urinary function at baseline due to an increase in urinary toxicity observed in patients treated with hypofractionated radiation in one study. Extreme hypofractionation (greater than or equal to 5 Gy/day), is currently being compared in a randomized trial. Early prospectively collected data from multiple institutions demonstrates efficacy and toxicity that compares favorably with historical controls. The cost savings from hypofractionation could be profound on a national level and only increases the necessity of testing hypofractionated treatment schedules. Long term data and future trials will help radiation oncologists determine the ideal fractionation scheme based on cost, efficacy, and toxicity. PMID:25606574

  10. A systematic review of hypofractionation for primary management of prostate cancer.

    PubMed

    Koontz, Bridget F; Bossi, Alberto; Cozzarini, Cesare; Wiegel, Thomas; D'Amico, Anthony

    2015-10-01

    Technological advances in radiation therapy delivery have permitted the use of high-dose-per-fraction radiation therapy (RT) for early-stage prostate cancer (PCa). Level 1 evidence supporting the safety and efficacy of hypofractionated RT is evolving as this modality becomes more widely utilized and refined. To perform a systematic review of the current evidence on the safety and efficacy of hypofractionated RT for early-stage PCa and to provide in-context recommendations for current application of this technology. Embase, PubMed, and Scopus electronic databases were queried for English-language articles from January 1990 through June 2014. Prospective studies with a minimum of 50 patients were included. Separate consideration was made for studies involving moderate hypofractionation (doses of 2.5-4Gy per fraction) and extreme hypofractionation (5-10Gy in 4-7 fractions). Six relatively small superiority designed randomized trials of standard fractionation versus moderate hypofractionation in predominantly low- and intermediate-risk PCa have been published with follow-up ranging from 4 to 8 yr, noting similar biochemical control (5-yr freedom from biochemical failure in modern studies is >80% for low-risk and intermediate-risk patients) and late grade ≥2 genitourinary and gastrointestinal toxicities (between 2% and 20%). Noninferiority studies are pending. In prospective phase 2 studies, extreme hypofractionation has promising 2- to 5-yr biochemical control rates of >90% for low-risk patients. Results from a randomized trial are expected in 2015. Moderate hypofractionation has 5-yr data to date establishing safety compared with standard fractionation, but 10-yr outcomes and longer follow-up are needed to establish noninferiority for clinical effectiveness. Extreme hypofractionation is promising but as yet requires reporting of randomized data prior to application outside of a clinical protocol. Hypofractionation for prostate cancer delivers relatively high doses

  11. WE-G-BRD-09: Novel MRI Compatible Electron Accelerator for MRI-Linac Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whelan, B; Keall, P; Gierman, S

    Purpose: MRI guided radiotherapy is a rapidly growing field; however current linacs are not designed to operate in MRI fringe fields. As such, current MRI- Linac systems require magnetic shielding, impairing MR image quality and system flexibility. Here, we present a bespoke electron accelerator concept with robust operation in in-line magnetic fields. Methods: For in-line MRI-Linac systems, electron gun performance is the major constraint on accelerator performance. To overcome this, we propose placing a cathode directly within the first accelerating cavity. Such a configuration is used extensively in high energy particle physics, but not previously for radiotherapy. Benchmarked computational modellingmore » (CST, Darmstadt, Germany) was employed to design and assess a 5.5 cell side coupled accelerator with a temperature limited thermionic cathode in the first accelerating cell. This simulation was coupled to magnetic fields from a 1T MRI model to assess robustness in magnetic fields for Source to Isocenter Distance between 1 and 2 meters. Performance was compared to a conventional electron gun based system in the same magnetic field. Results: A temperature limited cathode (work function 1.8eV, temperature 1245K, emission constant 60A/K/cm{sup 2}) will emit a mean current density of 24mA/mm{sup 2} (Richardson’s Law). We modeled a circular cathode with radius 2mm and mean current 300mA. Capture efficiency of the device was 43%, resulting in target current of 130 mA. The electron beam had a FWHM of 0.2mm, and mean energy of 5.9MeV (interquartile spread of 0.1MeV). Such an electron beam is suitable for radiotherapy, comparing favourably to conventional systems. This model was robust to operation the MRI fringe field, with a maximum current loss of 6% compared to 85% for the conventional system. Conclusion: The bespoke electron accelerator is robust to operation in in-line magnetic fields. This will enable MRI-Linacs with no accelerator magnetic shielding, and

  12. Short-course radiotherapy in elderly patients with glioblastoma: feasibility and efficacy of results from a single centre.

    PubMed

    Fariselli, L; Pinzi, V; Milanesi, I; Silvani, A; Marchetti, M; Farinotti, M; Salmaggi, A

    2013-06-01

    The incidence of glioblastoma (GBM) in the elderly population is currently increasing, with a peak seen between 65 and 84 years. The optimal treatment in terms of both efficacy and quality of life still remains a relevant and debated issue today. The purpose of our study was to evaluate the feasibility of short-course hypofractionated accelerated radiotherapy (HART) in GBM patients aged over 70 years and with a good Karnofsky performance score (KPS). A review of medical records at the "Istituto Neurologico C. Besta" was undertaken; patients aged ≥ 70 years who had undergone adjuvant HART for GBM between January 2000 and January 2004 were included in the study. HART was administered to a total dose of 45 Gy, 2.5 Gy/fraction, in three daily fractions for three consecutive days/cycle fractions each, delivered in two cycles (split 15 days). A total of 33 patients were evaluable for the current analysis. Median follow-up was 10 months. According to CTCAE (version 3.0) criteria, none of the patients developed radiation-induced neurological status deterioration or necrosis. KPS evaluation after HART was found to be stable in 73 % of patients, improved in 24 %, and worse in 3 %. The median overall survival time of the entire study population was 8 months (range 2-24). Our findings suggest that a hypofractionated accelerated schedule can be a safe and effective option in the treatment of GBM in the elderly.

  13. On the Detectability of Acoustic Waves Induced Following Irradiation by a Radiotherapy Linear Accelerator.

    PubMed

    Hickling, Susannah; Leger, Pierre; El Naqa, Issam

    2016-02-11

    Irradiating an object with a megavoltage photon beam generated by a clinical radiotherapy linear accelerator (linac) induces acoustic waves through the photoacoustic effect. The detection and characterization of such acoustic waves has potential applications in radiation therapy dosimetry. The purpose of this work was to gain insight into the properties of such acoustic waves by simulating and experimentally detecting them in a well-defined system consisting of a metal block suspended in a water tank. A novel simulation workflow was developed by combining radiotherapy Monte Carlo and acoustic wave transport simulation techniques. Different set-up parameters such as photon beam energy, metal block depth, metal block width, and metal block material were varied, and the simulated and experimental acoustic waveforms showed the same relative amplitude trends and frequency variations for such setup changes. The simulation platform developed in this work can easily be extended to other irradiation situations, and will be an invaluable tool for developing a radiotherapy dosimetry system based on the detection of the acoustic waves induced following linear accelerator irradiation.

  14. Dose characteristics of in-house-built collimators for stereotactic radiotherapy with a linear accelerator.

    PubMed

    Norrgård, F S; Sipilä, P M; Kulmala, J A; Minn, H R

    1998-06-01

    Dose characteristics of a stereotactic radiotherapy unit based on a standard Varian Clinac 4/100 4 MV linear accelerator, in-house-built Lipowitz collimators and the SMART stereotactic radiotherapy treatment planning software have been determined. Beam collimation is constituted from the standard collimators of the linear accelerator and a tertiary collimation consisting of a replaceable divergent Lipowitz collimator. Four collimators with isocentre diameters of 15, 25, 35 and 45 mm, respectively, were constructed. Beam characteristics were measured in air, acrylic or water with ionization chamber, photon diode, electron diode, diamond detector and film. Monte Carlo simulation was also applied. The radiation leakage under the collimators was less than 1% at 50 mm depth in water. Specific beam characteristics for each collimator were imported to SMART and dose planning with five non-coplanar converging 140 degrees arcs separated by 36 degrees angles was performed for treatment of a RANDO phantom. Dose verification was made with TLD and radiochromic film. The in-house-built collimators were found to be suitable for stereotactic radiotherapy and patient treatments with this system are in progress.

  15. Can Drugs Enhance Hypofractionated Radiotherapy? A Novel Method of Modeling Radiosensitization Using In Vitro Data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ohri, Nitin; Dicker, Adam P.; Lawrence, Yaacov Richard, E-mail: yaacovla@gmail.com

    2012-05-01

    Purpose: Hypofractionated radiotherapy (hRT) is being explored for a number of malignancies. The potential benefit of giving concurrent chemotherapy with hRT is not known. We sought to predict the effects of combined modality treatments by using mathematical models derived from laboratory data. Methods and Materials: Data from 26 published clonogenic survival assays for cancer cell lines with and without the use of radiosensitizing chemotherapy were collected. The first three data points of the RT arm of each assay were used to derive parameters for the linear quadratic (LQ) model, the multitarget (MT) model, and the generalized linear quadratic (gLQ) model.more » For each assay and model, the difference between the predicted and observed surviving fractions at the highest tested RT dose was calculated. The gLQ model was fitted to all the data from each RT cell survival assay, and the biologically equivalent doses in 2-Gy fractions (EQD2s) of clinically relevant hRT regimens were calculated. The increase in cell kill conferred by the addition of chemotherapy was used to estimate the EQD2 of hRT along with a radiosensitizing agent. For comparison, this was repeated using conventionally fractionated RT regimens. Results: At a mean RT dose of 8.0 Gy, the average errors for the LQ, MT, and gLQ models were 1.63, 0.83, and 0.56 log units, respectively, favoring the gLQ model (p < 0.05). Radiosensitizing chemotherapy increased the EQD2 of hRT schedules by an average of 28% to 82%, depending on disease site. This increase was similar to the gains predicted for the addition of chemotherapy to conventionally fractionated RT. Conclusions: Based on published in vitro assays, the gLQ equation is superior to the LQ and MT models in predicting cell kill at high doses of RT. Modeling exercises demonstrate that significant increases in biologically equivalent dose may be achieved with the addition of radiosensitizing agents to hRT. Clinical study of this approach is warranted.« less

  16. Hypofractionated Irradiation Has Immune Stimulatory Potential and Induces a Timely Restricted Infiltration of Immune Cells in Colon Cancer Tumors

    PubMed Central

    Frey, Benjamin; Rückert, Michael; Weber, Julia; Mayr, Xaver; Derer, Anja; Lotter, Michael; Bert, Christoph; Rödel, Franz; Fietkau, Rainer; Gaipl, Udo S.

    2017-01-01

    In addition to locally controlling the tumor, hypofractionated radiotherapy (RT) particularly aims to activate immune cells in the RT-modified microenvironment. Therefore, we examined whether hypofractionated RT can activate dendritic cells (DCs), induce immune cell infiltration in tumors, and how the chronology of immune cell migration into tumors occurs to gain knowledge for future definition of radiation breaks and inclusion of immunotherapy. Colorectal cancer treatments offer only limited survival benefit, and immunobiological principles for additional therapies need to be explored with preclinical models. The impact of hypofractionated RT on CT26 colon cancer tumor cell death, migration of DCs toward supernatants (SN) of tumor cells, and activation of DCs by SN were analyzed. The subcutaneous tumor of a BALB/c-CT26 mouse model was locally irradiated with 2 × 5 Gy, the tumor volume was monitored, and the infiltration of immune cells in the tumor was determined by flow cytometry daily. Hypofractionated RT induced a mixture of apoptotic and necrotic CT26 cells, which is known to be in particular immunogenic. DCs that migrated toward SN of CT26 cells particularly upregulated the activation markers CD80 and CD86 when in contact with SN of irradiated tumor cells. After hypofractionated RT, the tumor outgrowth was significantly retarded and in the irradiated tumors an increased infiltration of macrophages (CD11bhigh/F4-80+) and DCs (MHC-II+), but only between day 5 and 10 after the first irradiation, takes place. While CD4+ T cells migrated into non-irradiated and irradiated tumors, CD8+ T cells were only found in tumors that had been irradiated and they were highly increased at day 8 after the first irradiation. Myeloid-derived suppressor cells and regulatory T cells show regular turnover in irradiated and non-irradiated tumors. Tumor cell-specific anti-IgM antibodies were enhanced in the serum of animals with irradiated tumors. We conclude that

  17. Canadian Phase III Randomized Trial of Stereotactic Body Radiotherapy Versus Conventionally Hypofractionated Radiotherapy for Stage I, Medically Inoperable Non-Small-Cell Lung Cancer - Rationale and Protocol Design for the Ontario Clinical Oncology Group (OCOG)-LUSTRE Trial.

    PubMed

    Swaminath, Anand; Wierzbicki, Marcin; Parpia, Sameer; Wright, James R; Tsakiridis, Theodoros K; Okawara, Gordon S; Kundapur, Vijayananda; Bujold, Alexis; Ahmed, Naseer; Hirmiz, Khalid; Kurien, Elizabeth; Filion, Edith; Gabos, Zsolt; Faria, Sergio; Louie, Alexander V; Owen, Timothy; Wai, Elaine; Ramchandar, Kevin; Chan, Elisa K; Julian, Jim; Cline, Kathryn; Whelan, Timothy J

    2017-03-01

    We describe a Canadian phase III randomized controlled trial of stereotactic body radiotherapy (SBRT) versus conventionally hypofractionated radiotherapy (CRT) for the treatment of stage I medically inoperable non-small-cell lung cancer (OCOG-LUSTRE Trial). Eligible patients are randomized in a 2:1 fashion to either SBRT (48 Gy in 4 fractions for peripherally located lesions; 60 Gy in 8 fractions for centrally located lesions) or CRT (60 Gy in 15 fractions). The primary outcome of the study is 3-year local control, which we hypothesize will improve from 75% with CRT to 87.5% with SBRT. With 85% power to detect a difference of this magnitude (hazard ratio = 0.46), a 2-sided α = 0.05 and a 2:1 randomization, we require a sample size of 324 patients (216 SBRT, 108 CRT). Important secondary outcomes include overall survival, disease-free survival, toxicity, radiation-related treatment death, quality of life, and cost-effectiveness. A robust radiation therapy quality assurance program has been established to assure consistent and high quality SBRT and CRT delivery. Despite widespread interest and adoption of SBRT, there still remains a concern regarding long-term control and risks of toxicity (particularly in patients with centrally located lesions). The OCOG-LUSTRE study is the only randomized phase III trial testing SBRT in a medically inoperable population, and the results of this trial will attempt to prove that the benefits of SBRT outweigh the potential risks. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Monte Carlo radiotherapy simulations of accelerated repopulation and reoxygenation for hypoxic head and neck cancer

    PubMed Central

    Harriss-Phillips, W M; Bezak, E; Yeoh, E K

    2011-01-01

    Objective A temporal Monte Carlo tumour growth and radiotherapy effect model (HYP-RT) simulating hypoxia in head and neck cancer has been developed and used to analyse parameters influencing cell kill during conventionally fractionated radiotherapy. The model was designed to simulate individual cell division up to 108 cells, while incorporating radiobiological effects, including accelerated repopulation and reoxygenation during treatment. Method Reoxygenation of hypoxic tumours has been modelled using randomised increments of oxygen to tumour cells after each treatment fraction. The process of accelerated repopulation has been modelled by increasing the symmetrical stem cell division probability. Both phenomena were onset immediately or after a number of weeks of simulated treatment. Results The extra dose required to control (total cell kill) hypoxic vs oxic tumours was 15–25% (8–20 Gy for 5×2 Gy per week) depending on the timing of accelerated repopulation onset. Reoxygenation of hypoxic tumours resulted in resensitisation and reduction in total dose required by approximately 10%, depending on the time of onset. When modelled simultaneously, accelerated repopulation and reoxygenation affected cell kill in hypoxic tumours in a similar manner to when the phenomena were modelled individually; however, the degree was altered, with non-additive results. Simulation results were in good agreement with standard linear quadratic theory; however, differed for more complex comparisons where hypoxia, reoxygenation as well as accelerated repopulation effects were considered. Conclusion Simulations have quantitatively confirmed the need for patient individualisation in radiotherapy for hypoxic head and neck tumours, and have shown the benefits of modelling complex and dynamic processes using Monte Carlo methods. PMID:21933980

  19. Clinical benefits of new immobilization system for hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma by helical tomotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Yong; Zhou, Yong-Kang; Chen, Yi-Xing

    Objective: A comprehensive clinical evaluation was conducted, assessing the Body Pro-Lok immobilization and positioning system to facilitate hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma (HCC), using helical tomotherapy to improve treatment precision. Methods: Clinical applications of the Body Pro-Lok system were investigated (as above) in terms of interfractional and intrafractional setup errors and compressive abdominal breath control. To assess interfractional setup errors, a total of 42 patients who were given 5 to 20 fractions of helical tomotherapy for intrahepatic HCC were analyzed. Overall, 15 patients were immobilized using simple vacuum cushion (group A), and the Body Pro-Lok system was used inmore » 27 patients (group B), performing megavoltage computed tomography (MVCT) scans 196 times and 435 times, respectively. Pretreatment MVCT scans were registered to the planning kilovoltage computed tomography (KVCT) for error determination, and group comparisons were made. To establish intrafractional setup errors, 17 patients with intrahepatic HCC were selected at random for immobilization by Body Pro-Lok system, undergoing MVCT scans after helical tomotherapy every week. A total of 46 MVCT re-scans were analyzed for this purpose. In researching breath control, 12 patients, randomly selected, were immobilized by Body Pro-Lok system and subjected to 2-phase 4-dimensional CT (4DCT) scans, with compressive abdominal control or in freely breathing states, respectively. Respiratory-induced liver motion was then compared. Results: Mean interfractional setup errors were as follows: (1) group A: X, 2.97 ± 2.47 mm; Y, 4.85 ± 4.04 mm; and Z, 3.77 ± 3.21 mm; pitch, 0.66 ± 0.62°; roll, 1.09 ± 1.06°; and yaw, 0.85 ± 0.82°; and (2) group B: X, 2.23 ± 1.79 mm; Y, 4.10 ± 3.36 mm; and Z, 1.67 ± 1.91 mm; pitch, 0.45 ± 0.38°; roll, 0.77 ± 0.63°; and yaw, 0.52 ± 0.49°. Between-group differences were statistically significant in 6

  20. Hypofractionated Prostate Radiotherapy with or without Conventionally Fractionated Nodal Irradiation: Clinical Toxicity Observations and Retrospective Daily Dosimetry.

    PubMed

    McDonald, Andrew M; Bishop, Justin M; Jacob, Rojymon; Dobelbower, Michael C; Kim, Robert Y; Yang, Eddy S; Smith, Heather; Wu, Xingen; Fiveash, John B

    2012-01-01

    Purpose. To evaluate toxicity associated with the addition of elective nodal irradiation (ENI) to a hypofractionated regimen for the treatment of prostate cancer. Methods and Materials. Fifty-seven patients received pelvic image-guided IMRT to 50.4 Gy in 28 fractions with a hypofractionated simultaneous boost to the prostate to 70 Gy. Thirty-one patients received prostate-only treatment to 70 Gy in 28 fractions. Results. Median followup was 41.1 months. Early grade ≥2 urinary toxicity rates were 49% (28 of 57) for patients receiving ENI and 58% (18 of 31) for those not (P = 0.61). Early grade ≥2 rectal toxicity rates were 40% (23 of 57) and 23% (7 of 31), respectively (P = 0.09). The addition of ENI resulted in a 21% actuarial rate of late grade ≥2 rectal toxicity at 4 years, compared to 0% for patients treated to the prostate only (P = 0.02). Retrospective daily dosimetry of patients experiencing late rectal toxicity revealed an average increase of 2.67% of the rectal volume receiving 70 Gy compared to the original plan. Conclusions. The addition of ENI resulted in an increased risk of late rectal toxicity. Grade ≥2 late rectal toxicity was associated with worse daily rectal dosimetry compared to the treatment plan.

  1. Adoption of Hypofractionated Radiation Therapy for Breast Cancer After Publication of Randomized Trials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jagsi, Reshma, E-mail: rjagsi@med.umich.edu; Falchook, Aaron D.; Hendrix, Laura H.

    2014-12-01

    Purpose: Large randomized trials have established the noninferiority of shorter courses of “hypofractionated” radiation therapy (RT) to the whole breast compared to conventional courses using smaller daily doses in the adjuvant treatment of selected breast cancer patients undergoing lumpectomy. Hypofractionation is more convenient and less costly. Therefore, we sought to determine uptake of hypofractionated breast RT over time. Methods and Materials: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database, we identified 16,096 women with node-negative breast cancer and 4269 with ductal carcinoma in situ (DCIS) who received lumpectomy followed by more than 12 fractions of RT between 2004 andmore » 2010. Based on Medicare claims, we determined the number of RT treatments given and grouped patients into those receiving hypofractionation (13-24) or those receiving conventional fractionation (≥25). We also determined RT technique (intensity modulated RT or not) using Medicare claims. We evaluated patterns and correlates of hypofractionation receipt using bivariate and multivariable analyses. Results: Hypofractionation use was similar in patients with DCIS and those with invasive disease. Overall, the use of hypofractionation increased from 3.8% in 2006 to 5.4% in 2007, to 9.4% in 2008, and to 13.6% in 2009 and 2010. Multivariable analysis showed increased use of hypofractionation in recent years and in patients with older age, smaller tumors, increased comorbidity, higher regional education, and Western SEER regions. However, even in patients over the age of 80, the hypofractionation rate in 2009 to 2010 was only 25%. Use of intensity modulated RT (IMRT) also increased over time (from 9.4% in 2004 to 22.7% in 2009-2010) and did not vary significantly between patients receiving hypofractionation and those receiving traditional fractionation. Conclusions: Hypofractionation use increased among low-risk older US breast cancer patients with

  2. A novel electron accelerator for MRI-Linac radiotherapy.

    PubMed

    Whelan, Brendan; Gierman, Stephen; Holloway, Lois; Schmerge, John; Keall, Paul; Fahrig, Rebecca

    2016-03-01

    MRI guided radiotherapy is a rapidly growing field; however, current electron accelerators are not designed to operate in the magnetic fringe fields of MRI scanners. As such, current MRI-Linac systems require magnetic shielding, which can degrade MR image quality and limit system flexibility. The purpose of this work was to develop and test a novel medical electron accelerator concept which is inherently robust to operation within magnetic fields for in-line MRI-Linac systems. Computational simulations were utilized to model the accelerator, including the thermionic emission process, the electromagnetic fields within the accelerating structure, and resulting particle trajectories through these fields. The spatial and energy characteristics of the electron beam were quantified at the accelerator target and compared to published data for conventional accelerators. The model was then coupled to the fields from a simulated 1 T superconducting magnet and solved for cathode to isocenter distances between 1.0 and 2.4 m; the impact on the electron beam was quantified. For the zero field solution, the average current at the target was 146.3 mA, with a median energy of 5.8 MeV (interquartile spread of 0.1 MeV), and a spot size diameter of 1.5 mm full-width-tenth-maximum. Such an electron beam is suitable for therapy, comparing favorably to published data for conventional systems. The simulated accelerator showed increased robustness to operation in in-line magnetic fields, with a maximum current loss of 3% compared to 85% for a conventional system in the same magnetic fields. Computational simulations suggest that replacing conventional DC electron sources with a RF based source could be used to develop medical electron accelerators which are robust to operation in in-line magnetic fields. This would enable the development of MRI-Linac systems with no magnetic shielding around the Linac and reduce the requirements for optimization of magnetic fringe field, simplify design of

  3. A novel electron accelerator for MRI-Linac radiotherapy

    PubMed Central

    Whelan, Brendan; Gierman, Stephen; Holloway, Lois; Schmerge, John; Keall, Paul; Fahrig, Rebecca

    2016-01-01

    Purpose: MRI guided radiotherapy is a rapidly growing field; however, current electron accelerators are not designed to operate in the magnetic fringe fields of MRI scanners. As such, current MRI-Linac systems require magnetic shielding, which can degrade MR image quality and limit system flexibility. The purpose of this work was to develop and test a novel medical electron accelerator concept which is inherently robust to operation within magnetic fields for in-line MRI-Linac systems. Methods: Computational simulations were utilized to model the accelerator, including the thermionic emission process, the electromagnetic fields within the accelerating structure, and resulting particle trajectories through these fields. The spatial and energy characteristics of the electron beam were quantified at the accelerator target and compared to published data for conventional accelerators. The model was then coupled to the fields from a simulated 1 T superconducting magnet and solved for cathode to isocenter distances between 1.0 and 2.4 m; the impact on the electron beam was quantified. Results: For the zero field solution, the average current at the target was 146.3 mA, with a median energy of 5.8 MeV (interquartile spread of 0.1 MeV), and a spot size diameter of 1.5 mm full-width-tenth-maximum. Such an electron beam is suitable for therapy, comparing favorably to published data for conventional systems. The simulated accelerator showed increased robustness to operation in in-line magnetic fields, with a maximum current loss of 3% compared to 85% for a conventional system in the same magnetic fields. Conclusions: Computational simulations suggest that replacing conventional DC electron sources with a RF based source could be used to develop medical electron accelerators which are robust to operation in in-line magnetic fields. This would enable the development of MRI-Linac systems with no magnetic shielding around the Linac and reduce the requirements for optimization of

  4. Radiotherapy of Ductal Carcinoma In Situ

    PubMed Central

    Krug, David; Souchon, Rainer

    2015-01-01

    Summary Ductal carcinoma in situ (DCIS) is a heterogeneous disease in both its biology and clinical course. In the past, recurrence rates after breast-conserving surgery have been as high as 30% after 10 years. The introduction of mammography screening and advances in imaging have led to an increase in the detection of DCIS. The focus of this review is on the role of radiotherapy in the multidisciplinary treatment, including current developments in hypofractionation and boost delivery, and attempts to define low-risk subsets of DCIS for which the need for adjuvant radiation is repeatedly questioned. PMID:26600762

  5. Optimizing radiotherapy protocols using computer automata to model tumour cell death as a function of oxygen diffusion processes.

    PubMed

    Paul-Gilloteaux, Perrine; Potiron, Vincent; Delpon, Grégory; Supiot, Stéphane; Chiavassa, Sophie; Paris, François; Costes, Sylvain V

    2017-05-23

    The concept of hypofractionation is gaining momentum in radiation oncology centres, enabled by recent advances in radiotherapy apparatus. The gain of efficacy of this innovative treatment must be defined. We present a computer model based on translational murine data for in silico testing and optimization of various radiotherapy protocols with respect to tumour resistance and the microenvironment heterogeneity. This model combines automata approaches with image processing algorithms to simulate the cellular response of tumours exposed to ionizing radiation, modelling the alteration of oxygen permeabilization in blood vessels against repeated doses, and introducing mitotic catastrophe (as opposed to arbitrary delayed cell-death) as a means of modelling radiation-induced cell death. Published data describing cell death in vitro as well as tumour oxygenation in vivo are used to inform parameters. Our model is validated by comparing simulations to in vivo data obtained from the radiation treatment of mice transplanted with human prostate tumours. We then predict the efficacy of untested hypofractionation protocols, hypothesizing that tumour control can be optimized by adjusting daily radiation dosage as a function of the degree of hypoxia in the tumour environment. Further biological refinement of this tool will permit the rapid development of more sophisticated strategies for radiotherapy.

  6. Radiotherapy after surgical resection for head and neck mucosal melanoma.

    PubMed

    Wu, Abraham J; Gomez, Jennifer; Zhung, Joanne E; Chan, Kelvin; Gomez, Daniel R; Wolden, Suzanne L; Zelefsky, Michael J; Wolchok, Jedd D; Carvajal, Richard D; Chapman, Paul B; Wong, Richard J; Shaha, Ashok R; Kraus, Dennis H; Shah, Jatin P; Lee, Nancy Y

    2010-06-01

    To present our single-institution experience with postoperative radiotherapy for mucosal melanoma of the head and neck. Between 1992 and 2007, 27 patients with mucosal melanoma of the head and neck underwent surgical resection followed by postoperative radiotherapy. Median age was 68 years (range: 45-89 years). Sites included were sinonasal in 24 patients, oral cavity in 2, and oropharynx in 1. All but 2 patients had stage I disease. Twenty-two patients received hypofractionated radiation. Radiation techniques were intensity-modulated radiation therapy in 13, 3-dimensional conformal in 4, and conventional in 10. The median follow-up for living patients was 45 months (range: 24-122 months). The 3- and 5-year estimates of local progression-free, loco-regional progression-free, distant metastasis-free, and overall survival were: 47% and 35%; 34% and 22%; 30% and 24%; and 40% and 33%, respectively. Median time to local failure and distant metastasis was 32 and 14 months, respectively. Acute toxicities included 19% with grade 2 or higher mucositis. No late complications related to the optic structures were seen. Modern radiotherapeutic techniques including intensity-modulated radiation therapy appear feasible and well-tolerated in the postoperative treatment of head and neck mucosal melanoma. Unusual or serious late complications have not been observed despite extensive use of hypofractionated regimens. However, rates of local and distant failure remain high.

  7. Small animal radiotherapy research platforms

    NASA Astrophysics Data System (ADS)

    Verhaegen, Frank; Granton, Patrick; Tryggestad, Erik

    2011-06-01

    Advances in conformal radiation therapy and advancements in pre-clinical radiotherapy research have recently stimulated the development of precise micro-irradiators for small animals such as mice and rats. These devices are often kilovolt x-ray radiation sources combined with high-resolution CT imaging equipment for image guidance, as the latter allows precise and accurate beam positioning. This is similar to modern human radiotherapy practice. These devices are considered a major step forward compared to the current standard of animal experimentation in cancer radiobiology research. The availability of this novel equipment enables a wide variety of pre-clinical experiments on the synergy of radiation with other therapies, complex radiation schemes, sub-target boost studies, hypofractionated radiotherapy, contrast-enhanced radiotherapy and studies of relative biological effectiveness, to name just a few examples. In this review we discuss the required irradiation and imaging capabilities of small animal radiation research platforms. We describe the need for improved small animal radiotherapy research and highlight pioneering efforts, some of which led recently to commercially available prototypes. From this, it will be clear that much further development is still needed, on both the irradiation side and imaging side. We discuss at length the need for improved treatment planning tools for small animal platforms, and the current lack of a standard therein. Finally, we mention some recent experimental work using the early animal radiation research platforms, and the potential they offer for advancing radiobiology research.

  8. Choosing wisely after publication of level I evidence in breast cancer radiotherapy.

    PubMed

    Niska, Joshua R; Keole, Sameer R; Pockaj, Barbara A; Halyard, Michele Y; Patel, Samir H; Northfelt, Donald W; Gray, Richard J; Wasif, Nabil; Vargas, Carlos E; Wong, William W

    2018-01-01

    Recent trials in early-stage breast cancer support hypofractionated whole-breast radiotherapy (WBRT) as part of breast-conserving therapy (BCT). Evidence also suggests that radiotherapy (RT) omission may be reasonable for some patients over 70 years. Among radiation-delivery techniques, intensity-modulated RT (IMRT) is more expensive than 3-dimensional conformal RT (3DCRT). Based on this evidence, in 2013, the American Society for Radiation Oncology (ASTRO) recommended hypofractionated schedules for women aged ≥50 years with early-stage breast cancer and avoiding routine use of IMRT for WBRT. To assess response to level I evidence and adherence to ASTRO recommendations, we evaluated the pattern of RT use for early-stage breast cancer at our National Comprehensive Cancer Network institution from 2006 to 2008 and 2011 to 2013 and compared the results with national trends. Data from a prospective database were extracted to include patients treated with BCT, aged ≥50 years, with histologic findings of invasive ductal carcinoma, stage T1-T2N0M0, estrogen receptor-positive, and HER2 normal. We retrospectively reviewed the medical records and estimated costs based on 2016 Hospital Outpatient Prospective Payment System (technical fees) and Medicare Physician Fee Schedule (professional fees). Among 55 cases from 2006 to 2008, treatment regimens were 11% hypofractionated, 69% traditional schedule, and 20% RT omission (29% of patients were aged >70 years). Among 83 cases from 2011 to 2013, treatment regimens were 54% hypofractionated, 19% traditional schedule, and 27% RT omission (48% of patients were aged >70 years). 3DCRT was used for all WBRT treatments. Direct medical cost estimates were as follows: 15 fractions 3DCRT, $7,197.87; 15 fractions IMRT, $11,232.33; 25 fractions 3DCRT, $9,731.39; and 25 fractions IMRT, $16,877.45. Despite apparent resistance to shorter radiation schedules in the United States, we demonstrate that rapid practice change in response to level I

  9. Stereotactic hypofractionated radiotherapy in stage I (T1-2 N0 M0) non-small-cell lung cancer (NSCLC).

    PubMed

    Zimmermann, Frank B; Geinitz, Hans; Schill, Sabine; Thamm, Reinhard; Nieder, Carsten; Schratzenstaller, Ulrich; Molls, Michael

    2006-01-01

    Stereotactic Radiotherapy has the potential to produce high local control rates with low risk of severe lung toxicity. From December 2000 to January 2006, 68 inoperable patients (median age 76 years) with stage I NSCLC received definitive hSRT. A mean total dose of 37.5 Gy (24-40 Gy; 60%-isodose) in 3-5 fractions was applied. Immobilisation was carried out by means of a vacuum couch and low pressure foil (Medical Intelligence, Schwab München, Germany). Staging procedures were thoracic and abdominal CT-scan, FDG-PET and CT or MRI of the brain in all patients. Clinical target volume was the tumor as seen in lung windowing of CT and in FDG-PET. Organ movements (6-22 mm) and patient positioning in the couch (3-12 mm) were added as safety margin for the definition of the planning target volume (PTV), that was enclosed by the 60%-isodose. We observed four (6%) local tumor recurrences, resulting in an actuarial local tumor control rate of 96%, 88% and 88% after 1, 2 and 3 year follow-up. Nineteen patients died, with eight patients due to cancer (12%), two to local tumor progression alone. Cancer-specific survival is 96%, 82% and 73% at 1, 2 and 3 years. Eleven patients died from comorbidities, making a 53% overall 3-year survival. Fifty five percent of the patients were affected by mild acute and subacute side effects, with only 3% experiencing pneumonitis III degrees . Late effects were pneumonitis III degrees in 1%, rib fractures in 3%, and benign pleural effusion in 2 patients. Hypofractionated SRT is safe even in elderly patients with stage I NSCLC and significantly reduced lung capacity. It leads to high local control rates and should be offered to patients not amenable for curative resection.

  10. Current role of modern radiotherapy techniques in the management of breast cancer

    PubMed Central

    Ozyigit, Gokhan; Gultekin, Melis

    2014-01-01

    Breast cancer is the most common type of malignancy in females. Advances in systemic therapies and radiotherapy (RT) provided long survival rates in breast cancer patients. RT has a major role in the management of breast cancer. During the past 15 years several developments took place in the field of imaging and irradiation techniques, intensity modulated RT, hypofractionation and partial-breast irradiation. Currently, improvements in the RT technology allow us a subsequent decrease in the treatment-related complications such as fibrosis and long-term cardiac toxicity while improving the loco-regional control rates and cosmetic results. Thus, it is crucial that modern radiotherapy techniques should be carried out with maximum care and efficiency. Several randomized trials provided evidence for the feasibility of modern radiotherapy techniques in the management of breast cancer. However, the role of modern radiotherapy techniques in the management of breast cancer will continue to be defined by the mature results of randomized trials. Current review will provide an up-to-date evidence based data on the role of modern radiotherapy techniques in the management of breast cancer. PMID:25114857

  11. Hyperfractionated Accelerated Radiotherapy (HART) for Anaplastic Thyroid Carcinoma: Toxicity and Survival Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dandekar, Prasad; Harmer, Clive; Barbachano, Yolanda

    2009-06-01

    Purpose: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive cancers, and the current protocol of hyperfractionated accelerated radiotherapy was initiated to improve survival while limiting toxicities. Methods and Materials: All patients with ATC from 1991 to 2002 were accrued and received megavoltage radiotherapy from the mastoid processes to the carina up to 60 Gy in twice-daily fractions of 1.8 and 2 Gy, 6 hours apart. Results: Thirty-one patients were accrued with a median age of 69 years, and 55% were women. Debulking was performed in 26%, and total thyroidectomy, in 6%, whereas 68% received radical radiotherapy alone. Localmore » control data were available for 27 patients: 22% had a complete response, 26% had a partial response, 15% showed progressive disease, and 37% showed static disease. Median overall survival for all 31 patients was 70 days (95% confidence interval, 40-99). There was no significant difference in median survival between patients younger (70 days) and older than 70 years (42 days), between men (70 days) and women (49days), and between patients receiving postoperative radiotherapy (77 days) and radical radiotherapy alone (35 days). Grade III or higher skin erythema was seen in 56% patients; desquamation in 21%; dysphagia in 74%; and esophagitis in 79%. Conclusion: The current protocol failed to offer a significant survival benefit, was associated with severe toxicities, and thus was discontinued. There is a suggestion that younger patients with operable disease have longer survival, but this would require a larger study to confirm it.« less

  12. Hypofractionated high-energy proton-beam irradiation is an alternative treatment for WHO grade I meningiomas.

    PubMed

    Vlachogiannis, Pavlos; Gudjonsson, Olafur; Montelius, Anders; Grusell, Erik; Isacsson, Ulf; Nilsson, Kristina; Blomquist, Erik

    2017-12-01

    Radiation treatment is commonly employed in the treatment of meningiomas. The aim of this study was to evaluate the effectiveness and safety of hypofractionated high-energy proton therapy as adjuvant or primary treatment for WHO grade I meningiomas. A total of 170 patients who received irradiation with protons for grade I meningiomas between 1994 and 2007 were included in the study. The majority of the tumours were located at the skull base (n = 155). Eighty-four patients were treated post subtotal resection, 42 at tumour relapse and 44 with upfront radiotherapy after diagnosis based on the typical radiological image. Irradiation was given in a hypofractionated fashion (3-8 fractions, usually 5 or 6 Gy) with a mean dose of 21.9 Gy (range, 14-46 Gy). All patients were planned for follow-up with clinical controls and magnetic resonance imaging scans at 6 months and 1, 2, 3, 5, 7 and 10 years after treatment. The median follow-up time was 84 months. Age, gender, tumour location, Simpson resection grade and target volume were assessed as possible prognostic factors for post-irradiation tumour progression and radiation related complications. The actuarial 5- and 10-year progression-free survival rates were 93% and 85% respectively. Overall mortality rate was 13.5%, while disease-specific mortality was 1.7% (3/170 patients). Older patients and patients with tumours located in the middle cranial fossa had a lower risk for tumour progression. Radiation-related complications were seen in 16 patients (9.4%), with pituitary insufficiency being the most common. Tumour location in the anterior cranial fossa was the only factor that significantly increased the risk of complications. Hypofractionated proton-beam radiation therapy may be used particularly in the treatment of larger World Health Organisation grade I meningiomas not amenable to total surgical resection. Treatment is associated with high rates of long-term tumour growth control and acceptable risk for

  13. Breast interest group faculty of radiation oncology: Australian and New Zealand patterns of practice survey on breast radiotherapy.

    PubMed

    Nguyen, Kimberley; Mackenzie, Penny; Allen, Angela; Dreosti, Marcus; Morgia, Marita; Zissiadis, Yvonne; Lamoury, Gilian; Windsor, Apsara

    2017-08-01

    This patterns of practice study was conducted on behalf of the RANZCR Breast Interest Group in order to document current radiotherapy practices for breast cancer in Australia and New Zealand. The survey identifies variations and highlights potential contentious aspects of radiotherapy management of breast cancer. A fifty-eight question survey was disseminated via the Survey Monkey digital platform to 388 Radiation Oncologists in Australia and New Zealand. In total, 156 responses were received and collated. Areas of notable consensus among respondents included hypofractionation (77.3% of respondents would 'always' or 'sometimes' consider hypofractionation in the management of ductal carcinoma in-situ and 99.3% in early invasive breast cancer); margin status in early breast cancer (73.8% believe a clear inked margin is sufficient and does not require further surgery) and use of bolus in post-mastectomy radiotherapy (PMRT) (91.1% of participants use bolus in PMRT). Areas with a wider degree of variability amongst respondents included regional nodal irradiation and components of radiotherapy planning and delivery (examples include the technique used for delivery of boost and frequency of bolus application for PMRT). The results of these patterns of practice survey informs radiation oncologists in Australia and New Zealand of the current clinical practices being implemented by their peers. The survey identifies areas of consensus and contention, the latter of which may lead to a development of research trials and/or educational activities to address these areas of uncertainty. © 2016 The Royal Australian and New Zealand College of Radiologists.

  14. Stereotactic body radiotherapy for lung cancer: how much does it really cost?

    PubMed

    Lievens, Yolande; Obyn, Caroline; Mertens, Anne-Sophie; Van Halewyck, Dries; Hulstaert, Frank

    2015-03-01

    Despite the lack of randomized evidence, stereotactic body radiotherapy (SBRT) is being accepted as superior to conventional radiotherapy for patients with T1-2N0 non-small-cell lung cancer in the periphery of the lung and unfit or unwilling to undergo surgery. To introduce SBRT in a system of coverage with evidence development, a correct financing had to be determined. A time-driven activity-based costing model for radiotherapy was developed. Resource cost calculation of all radiotherapy treatments, standard and innovative, was conducted in 10 Belgian radiotherapy centers in the second half of 2012. The average cost of lung SBRT across the 10 centers (6221&OV0556;) is in the range of the average costs of standard fractionated 3D-conformal radiotherapy (5919&OV0556;) and intensity-modulated radiotherapy (7379&OV0556;) for lung cancer. Hypofractionated 3D-conformal radiotherapy and intensity-modulated radiotherapy schemes are less costly (3993&OV0556; respectively 4730&OV0556;). The SBRT cost increases with the number of fractions and is highly dependent of personnel and equipment use. SBRT cost varies more by centre than conventional radiotherapy cost, reflecting different technologies, stages in the learning curve and a lack of clear guidance in this field. Time-driven activity-based costing of radiotherapy is feasible in a multicentre setup, resulting in real-life resource costs that can form the basis for correct reimbursement schemes, supporting an early yet controlled introduction of innovative radiotherapy techniques in clinical practice.

  15. Role of radiotherapy fractionation in head and neck cancers (MARCH): an updated meta-analysis

    PubMed Central

    Lacas, Benjamin; Bourhis, Jean; Overgaard, Jens; Zhang, Qiang; Gregoire, Vincent; Nankivell, Matthew; Zackrisson, Bjorn; Szutkowski, Zbigniew; Suwiński, Rafał; Poulsen, Michael; O’Sullivan, Brian; Corvo, Renzo; Laskar, Sarbani Ghosh; Fallai, Carlo; Yamazaki, Hideya; Dobrowsky, Werner; Cho, Kwan Ho; Garden, Adam S; Langendijk, Johannes A; Viegas, Celia Maria Pais; Hay, John; Lotayef, Mohamed; Parmar, Mahesh K B; Auperin, Anne; van Herpen, Carla; Maingon, Philippe; Trotti, Andy M; Grau, Cai; Pignon, Jean-Pierre; Blanchard, Pierre

    2017-01-01

    Summary Background The Meta-Analysis of Radiotherapy in squamous cell Carcinomas of Head and neck (MARCH) showed that altered fractionation radiotherapy is associated with improved overall and progression-free survival compared with conventional radiotherapy, with hyperfractionated radiotherapy showing the greatest benefit. This update aims to confirm and explain the superiority of hyperfractionated radiotherapy over other altered fractionation radiotherapy regimens and to assess the benefit of altered fractionation within the context of concomitant chemotherapy with the inclusion of new trials. Methods For this updated meta-analysis, we searched bibliography databases, trials registries, and meeting proceedings for published or unpublished randomised trials done between Jan 1, 2009, and July 15, 2015, comparing primary or postoperative conventional fractionation radiotherapy versus altered fractionation radiotherapy (comparison 1) or conventional fractionation radiotherapy plus concomitant chemotherapy versus altered fractionation radiotherapy alone (comparison 2). Eligible trials had to start randomisation on or after Jan 1, 1970, and completed accrual before Dec 31, 2010; had to have been randomised in a way that precluded prior knowledge of treatment assignment; and had to include patients with non-metastatic squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx undergoing first-line curative treatment. Trials including a non-conventional radiotherapy control group, investigating hypofractionated radiotherapy, or including mostly nasopharyngeal carcinomas were excluded. Trials were grouped in three types of altered fractionation: hyperfractionated, moderately accelerated, and very accelerated. Individual patient data were collected and combined with a fixed-effects model based on the intention-to-treat principle. The primary endpoint was overall survival. Findings Comparison 1 (conventional fractionation radiotherapy vs altered

  16. Visual Outcome in Meningiomas Around Anterior Visual Pathways Treated With Linear Accelerator Fractionated Stereotactic Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stiebel-Kalish, Hadas, E-mail: kalishhadas@gmail.com; Sackler School of Medicine, Tel Aviv University, Tel Aviv; Reich, Ehud

    Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems. The purpose of our study was to describe a case series of AVP meningiomas treated with linear accelerator fractionated stereotactic radiotherapy (FSRT) using the multiple, noncoplanar, dynamic conformal rotation paradigm and to compare the success and complication rates with those reported for other techniques. Patients and Methods: We included all patients with AVP meningiomas followed up atmore » our neuro-ophthalmology unit for a minimum of 12 months after FSRT. We compared the details of the neuro-ophthalmologic examinations and tumor size before and after FSRT and at the end of follow-up. Results: Of 87 patients with AVP meningiomas, 17 had been referred for FSRT. Of the 17 patients, 16 completed >12 months of follow-up (mean 39). Of the 16 patients, 11 had undergone surgery before FSRT and 5 had undergone FSRT as first-line management. Tumor control was achieved in 14 of the 16 patients, with three meningiomas shrinking in size after RT. Two meningiomas progressed, one in an area that was outside the radiation field. The visual function had improved in 6 or stabilized in 8 of the 16 patients (88%) and worsened in 2 (12%). Conclusions: Linear accelerator fractionated RT using the multiple noncoplanar dynamic rotation conformal paradigm can be offered to patients with meningiomas that threaten the anterior visual pathways as an adjunct to surgery or as first-line treatment, with results comparable to those reported for other stereotactic RT techniques.« less

  17. Hypofractionated stereotactic radiation therapy in three to five fractions for vestibular schwannoma.

    PubMed

    Morimoto, Masahiro; Yoshioka, Yasuo; Kotsuma, Tadayuki; Adachi, Kana; Shiomi, Hiroya; Suzuki, Osamu; Seo, Yuji; Koizumi, Masahiko; Kagawa, Naoki; Kinoshita, Manabu; Hashimoto, Naoya; Ogawa, Kazuhiko

    2013-08-01

    To retrospectively examine the outcomes of hypofractionated stereotactic radiation therapy in three to five fractions for vestibular schwannomas. Twenty-five patients with 26 vestibular schwannomas were treated with hypofractionated stereotactic radiation therapy using a CyberKnife. The vestibular schwannomas of 5 patients were associated with type II neurofibromatosis. The median follow-up time was 80 months (range: 6-167); the median planning target volume was 2.6 cm(3) (0.3-15.4); and the median prescribed dose (≥D90) was 21 Gy in three fractions (18-25 Gy in three to five fractions). Progression was defined as ≥2 mm 3-dimensional post-treatment tumor enlargement excluding transient expansion. Progression or any death was counted as an event in progression-free survival rates, whereas only progression was counted in progression-free rates. The 7-year progression-free survival and progression-free rates were 78 and 95%, respectively. Late adverse events (≥3 months) with grades based on Common Terminology Criteria for Adverse Events, v4.03 were observed in 6 patients: Grade 3 hydrocephalus in one patient, Grade 2 facial nerve disorders in two and Grade 1-2 tinnitus in three. In total, 12 out of 25 patients maintained pure tone averages ≤50 dB before hypofractionated stereotactic radiation therapy, and 6 of these 12 patients (50%) maintained pure tone averages at this level at the final audiometric follow-up after hypofractionated stereotactic radiation therapy. However, gradient deterioration of pure tone average was observed in 11 of these 12 patients. The mean pure tone averages before hypofractionated stereotactic radiation therapy and at the final follow-up for the aforementioned 12 patients were 29.8 and 57.1 dB, respectively. Treating vestibular schwannomas with hypofractionated stereotactic radiation therapy in three to five fractions may prevent tumor progression with tolerable toxicity. However, gradient deterioration of pure tone average was

  18. Accelerated partial breast irradiation using robotic radiotherapy: a dosimetric comparison with tomotherapy and three-dimensional conformal radiotherapy.

    PubMed

    Rault, Erwann; Lacornerie, Thomas; Dang, Hong-Phuong; Crop, Frederik; Lartigau, Eric; Reynaert, Nick; Pasquier, David

    2016-02-27

    Accelerated partial breast irradiation (APBI) is a new breast treatment modality aiming to reduce treatment time using hypo fractionation. Compared to conventional whole breast irradiation that takes 5 to 6 weeks, APBI is reported to induce worse cosmetic outcomes both when using three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT). These late normal tissue effects may be attributed to the dose volume effect because a large portion of the non-target breast tissue volume (NTBTV) receives a high dose. In the context of APBI, non-coplanar beams could spare the NTBTV more efficiently. This study evaluates the dosimetric benefit of using the Cyberknife (CK) for APBI in comparison to IMRT (Tomotherapy) and three dimensional conformal radiotherapy (3D-CRT). The possibility of using surgical clips, implanted during surgery, to track target movements is investigated first. A phantom of a female thorax was designed in-house using the measurements of 20 patients. Surgical clips of different sizes were inserted inside the breast. A treatment plan was delivered to the mobile and immobile phantom. The motion compensation accuracy was evaluated using three radiochromic films inserted inside the breast. Three dimensional conformal radiotherapy (3D-CRT), Tomotherapy (TOMO) and CK treatment plans were calculated for 10 consecutive patients who received APBI in Lille. To ensure a fair comparison of the three techniques, margins applied to the CTV were set to 10 mm. However, a second CK plan was prepared using 3 mm margins to evaluate the benefits of motion compensation. Only the larger clips (VITALITEC Medium-Large) could be tracked inside the larger breast (all gamma indices below 1 for 1 % of the maximum dose and 1 mm). All techniques meet the guidelines defined in the NSABP/RTOG and SHARE protocols. As the applied dose volume constraints are very strong, insignificant dosimetric differences exist between techniques regarding the PTV

  19. P13.11USAGE OF CYBER KNIFE HYPOFRACTIONATED RADIOSURGERY IN HIGH GRADE GLIOMAS COMPLEX TREATMENT

    PubMed Central

    Glavatskyi, O.; Buryk, V.M.; Kardash, K.A.; Pylypas, O.P.; Chebotaryova, T.I.

    2014-01-01

    INTRODUCTION: A complex approach to the treatment of malignant brain tumors includes maximum surgical resection, radiotherapy and chemotherapy. The purpose of the current study is to review retrospectively the ability of Cyber Knife (“Accuray Incorporated”, Sunnyvale, CA, USA) radiosurgery to provide local tumor control of newly diagnosed or recurrent malignant brain tumors. MATERIAL AND METHOD: 26 patients with malignant brain tumors (glioblastoma multiform (GBM) - 14 patients, anaplastic astrocytoma (AA) - 12 patients) were treated in 2012-2013 with Cyber Knife stereotactic radiosurgery. Before radiosurgery 8 patients had complete removal of the tumor, 9 patients had subtotal resection and 9 patients had biopsy. 17 patients received adjuvant chemotherapy with temozolomide according to the different treatment protocols. 9 patients who were previously irradiated received re-irradiation. In all patients CT, MRI, PET (native, enhanced, CT-perfusion, MRI-diffusion (DWI) studies) before and after treatment were performed with (3, 6, 12, 18 month follow up). The volume of tumors ranged from 10-12 cm3 to 101,1 cm3. The maximum mean dose of irradiation applied was 36.99 Gy (ranged from 21,3 Gy to 48,8 Gy). 3-6 fractions of hypofractionated treatment were used. RESULTS: At this stage of the study, we assessed the absence of complications after stereotactic hypofractionated radiosurgery. Objective survival evaluation has being performed in 12-24 months after radiosurgical treatment. A significant decrease in the number and severity of seizures was seen in 7 patients out of 21 (33 %). 18 patients (64%) had regression of limb weakness. In case of biopsy 7 of 9 tumors (78 %) showed a decrease in volume. In patients with clinical deterioration (3 patients) repeated surgical treatment was performed. All of them had signs of post-irradiation necrosis and pathomorphosis in tumor tissue. Median overall survival and progression free survival were 17 months and 11 months

  20. Targeted Alpha Therapy: The US DOE Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy

    NASA Astrophysics Data System (ADS)

    John, Kevin

    2017-01-01

    Targeted radiotherapy is an emerging discipline of cancer therapy that exploits the biochemical differences between normal cells and cancer cells to selectively deliver a lethal dose of radiation to cancer cells, while leaving healthy cells relatively unperturbed. A broad overview of targeted alpha therapy including isotope production methods, and associated isotope production facility needs, will be provided. A more general overview of the US Department of Energy Isotope Program's Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy will also be presented focusing on the accelerator-production of 225Ac and final product isolation methodologies for medical applications.

  1. Oesophagus side effects related to the treatment of oesophageal cancer or radiotherapy of other thoracic malignancies.

    PubMed

    Adebahr, Sonja; Schimek-Jasch, Tanja; Nestle, Ursula; Brunner, Thomas B

    2016-08-01

    The oesophagus as a serial organ located in the central chest is frequent subject to "incidental" dose application in radiotherapy for several thoracic malignancies including oesophageal cancer itself. Especially due to the radiosensitive mucosa severe radiotherapy induced sequelae can occur, acute oesophagitis and strictures as late toxicity being the most frequent side-effects. In this review we focus on oesophageal side effects derived from treatment of gastrointestinal cancer and secondly provide an overview on oesophageal toxicity from conventional and stereotactic fractionated radiotherapy to the thoracic area in general. Available data on pathogenesis, frequency, onset, and severity of oesophageal side effects are summarized. Whereas for conventional radiotherapy the associations of applied doses to certain volumes of the oesophagus are well described, the tolerance dose to the mediastinal structures for hypofractionated therapy is unknown. The review provides available attempts to predict the risk of oesophageal side effects from dosimetric parameters of SBRT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. SU-F-J-130: Margin Determination for Hypofractionated Partial Breast Irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Geady, C; Keller, B; Hahn, E

    2016-06-15

    Purpose: To determine the Planning Target Volume (PTV) margin for Hypofractionated Partial Breast Irradiation (HPBI) using the van Herk formalism (M=2.5∑+0.7σ). HPBI is a novel technique intended to provide local control in breast cancer patients not eligible for surgical resection, using 40 Gy in 5 fractions prescribed to the gross disease. Methods: Setup uncertainties were quantified through retrospective analysis of cone-beam computed tomography (CBCT) data sets, collected prior to (prefraction) and after (postfraction) treatment delivery. During simulation and treatment, patients were immobilized using a wing board and an evacuated bag. Prefraction CBCT was rigidly registered to planning 4-dimensional computed tomographymore » (4DCT) using the chest wall and tumor, and translational couch shifts were applied as needed. This clinical workflow was faithfully reproduced in Pinnacle (Philips Medical Systems) to yield residual setup and intrafractional error through translational shifts and rigid registrations (ribs and sternum) of prefraction CBCT to 4DCT and postfraction CBCT to prefraction CBCT, respectively. All ten patients included in this investigation were medically inoperable; the median age was 84 (range, 52–100) years. Results: Systematic (and random) setup uncertainties (in mm) detected for the left-right, craniocaudal and anteroposterior directions were 0.4 (1.5), 0.8 (1.8) and 0.4 (1.0); net uncertainty was determined to be 0.7 (1.5). Rotations >2° in any axis occurred on 8/72 (11.1%) registrations. Conclusion: Preliminary results suggest a non-uniform setup margin (in mm) of 2.2, 3.3 and 1.7 for the left-right, craniocaudal and anteroposterior directions is required for HPBI, given its immobilization techniques and online setup verification protocol. This investigation is ongoing, though published results from similar studies are consistent with the above findings. Determination of margins in breast radiotherapy is a paradigm shift, but a

  3. [Practice evolution of hypofractionation in breast radiation therapy and medical impact].

    PubMed

    Dupin, C; Vilotte, F; Lagarde, P; Petit, A; Breton-Callu, C

    2016-06-01

    Whole breast irradiation after conservative surgery is the standard treatment for invasive breast cancer. Randomized studies indicate that hypofractionation can be equivalent for selected patients. This study focuses on fractionation practice evolution in a single centre, and analyses the economic impact of practice modification. All prescriptions for invasive breast cancer between January 2010 and June 2014 were analyzed. Female patients 60 years or older, pN0 were considered for the economic study. Patients included in clinical trials or patient with high-grade tumours were excluded from the hypofractionation practice study, because physician could not choose fractionation. We used data from the Medical public health system to calculate cost per fraction and transportation cost. Two thousand thirty one patients were treated; 399 were eligible for the economic study (20%) and 282 for the practice study (14%). Treatment with 25 fractions decreased from 90% to 16% in the first half of 2014. Meanwhile, treatment with 15 or 16 fractions increased from 6% in 2010 to 68% in the first half of 2014. Hypofractionated treatment proportion was 100% with 42.5Gy in 16 fractions in 2010 and 100% 40Gy in 15 fractions in 2014, according to long-term follow-up publication of START trials. Treatment with five fractions remained stable around 7% (4 to 16%), reserved for patients over 80 years (P<0.0001). Based on data from 3451 fractions in 2013, transport cost was calculated at 62 € per fraction, in addition to a 170.77 € reimbursement per fraction, giving a cost per fraction of 232.77 €. Practice change led to an increase of hypofractionation in recent years. Hypofractionation may be currently prescribed and may concern 20% of patients. This practice evolution is beneficial for patients and the public health system. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  4. Fiducial marker guided prostate radiotherapy: a review

    PubMed Central

    Jain, Suneil; Hounsell, Alan R; O'Sullivan, Joe M

    2016-01-01

    Image-guided radiotherapy (IGRT) is an essential tool in the accurate delivery of modern radiotherapy techniques. Prostate radiotherapy positioned using skin marks or bony anatomy may be adequate for delivering a relatively homogeneous whole-pelvic radiotherapy dose, but these surrogates are not reliable when using reduced margins, dose escalation or hypofractionated stereotactic radiotherapy. Fiducial markers (FMs) for prostate IGRT have been in use since the 1990s. They require surgical implantation and provide a surrogate for the position of the prostate gland. A variety of FMs are available and they can be used in a number of ways. This review aimed to establish the evidence for using prostate FMs in terms of feasibility, implantation procedures, types of FMs used, FM migration, imaging modalities used and the clinical impact of FMs. A search strategy was defined and a literature search was carried out in Medline. Inclusion and exclusion criteria were applied, which resulted in 50 articles being included in this review. The evidence demonstrates that FMs provide a more accurate surrogate for the position of the prostate than either external skin marks or bony anatomy. A combination of FM alignment and soft-tissue analysis is currently the most effective and widely available approach to ensuring accuracy in prostate IGRT. FM implantation is safe and well tolerated. FM migration is possible but minimal. Standardization of all techniques and procedures in relation to the use of prostate FMs is required. Finally, a clinical trial investigating a non-surgical alternative to prostate FMs is introduced. PMID:27585736

  5. Whole-Pelvic Nodal Radiation Therapy in the Context of Hypofractionation for High-Risk Prostate Cancer Patients: A Step Forward

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kaidar-Person, Orit; Roach, Mack; Créhange, Gilles, E-mail: gcrehange@cgfl.fr

    2013-07-15

    Given the low α/β ratio of prostate cancer, prostate hypofractionation has been tested through numerous clinical studies. There is a growing body of literature suggesting that with high conformal radiation therapy and even with more sophisticated radiation techniques, such as high-dose-rate brachytherapy or image-guided intensity modulated radiation therapy, morbidity associated with shortening overall treatment time with higher doses per fraction remains low when compared with protracted conventional radiation therapy to the prostate only. In high-risk prostate cancer patients, there is accumulating evidence that either dose escalation to the prostate or hypofractionation may improve outcome. Nevertheless, selected patients who have amore » high risk of lymph node involvement may benefit from whole-pelvic radiation therapy (WPRT). Although combining WPRT with hypofractionated prostate radiation therapy is feasible, it remains investigational. By combining modern advances in radiation oncology (high-dose-rate prostate brachytherapy, intensity modulated radiation therapy with an improved image guidance for soft-tissue sparing), it is hypothesized that WPRT could take advantage of recent results from hypofractionation trials. Moreover, the results from hypofractionation trials raise questions as to whether hypofractionation to pelvic lymph nodes with a high risk of occult involvement might improve the outcomes in WPRT. Although investigational, this review discusses the challenging idea of WPRT in the context of hypofractionation for patients with high-risk prostate cancer.« less

  6. Geographic Disparity in the Use of Hypofractionated Radiation Therapy Among Elderly Women Undergoing Breast Conservation for Invasive Breast Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gillespie, Erin F.; Matsuno, Rayna K.; Xu, Beibei

    Purpose: To evaluate geographic heterogeneity in the delivery of hypofractionated radiation therapy (RT) for breast cancer among Medicare beneficiaries across the United States. Methods and Materials: We identified 190,193 patients from the Centers for Medicare and Medicaid Services Chronic Conditions Warehouse. The study included patients aged >65 years diagnosed with invasive breast cancer treated with breast conservation surgery followed by radiation diagnosed between 2000 and 2012. We analyzed data by hospital referral region based on patient residency ZIP code. The proportion of women who received hypofractionated RT within each region was analyzed over the study period. Multivariable logistic regression models identified predictors ofmore » hypofractionated RT. Results: Over the entire study period we found substantial geographic heterogeneity in the use of hypofractionated RT. The proportion of women receiving hypofractionated breast RT in individual hospital referral regions varied from 0% to 61%. We found no correlation between the use of hypofractionated RT and urban/rural setting or general geographic region. The proportion of hypofractionated RT increased in regions with higher density of radiation oncologists, as well as lower total Medicare reimbursements. Conclusions: This study demonstrates substantial geographic heterogeneity in the use of hypofractionated RT among elderly women with invasive breast cancer treated with lumpectomy in the United States. This heterogeneity persists despite clinical data from multiple randomized trials proving efficacy and safety compared with standard fractionation, and highlights possible inefficiency in health care delivery.« less

  7. Comparison of proton beam radiotherapy and hyper-fractionated accelerated chemoradiotherapy for locally advanced pancreatic cancer.

    PubMed

    Maemura, Kosei; Mataki, Yuko; Kurahara, Hiroshi; Kawasaki, Yota; Iino, Satoshi; Sakoda, Masahiko; Ueno, Shinichi; Arimura, Takeshi; Higashi, Ryutaro; Yoshiura, Takashi; Shinchi, Hiroyuki; Natsugoe, Shoji

    We compared the clinical outcomes of proton beam radiotherapy (PBRT) and those of conventional chemoradiotherapy via hyper-fractionated acceleration radiotherapy (HART) after induction chemotherapy in patients with locally advanced pancreatic cancer (LAPC). Twenty-five consecutive patients with LAPC received induction chemotherapy comprising gemcitabine and S-1 before radiotherapy. Of these, 15 and 10 were enrolled in the HART and PBRT groups, respectively. Moderate hematological toxicities were observed only in the HART group, whereas two patients in the PBRT group developed duodenal ulcers. All patients underwent scheduled radiotherapy, with overall disease control rates of 93% and 80% in the HART and PBRT groups, respectively. Local progression was observed in 60% and 40% of patients in the HART and PBRT groups, respectively. However, there was no statistical significance between the two groups regarding the median time to progression (15.4 months in both) and the median overall survival (23.4 v.s. 22.3 months). PBRT was feasible and tolerable, and scheduled protocols could be completed with careful attention to gastrointestinal ulcers. Despite the lower incidence of local recurrence, PBRT did not yield obvious progression control and survival benefits relative to conventional chemoradiotherapy. Copyright © 2017 IAP and EPC. Published by Elsevier B.V. All rights reserved.

  8. Technical Note: Introduction of variance component analysis to setup error analysis in radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matsuo, Yukinori, E-mail: ymatsuo@kuhp.kyoto-u.ac.

    Purpose: The purpose of this technical note is to introduce variance component analysis to the estimation of systematic and random components in setup error of radiotherapy. Methods: Balanced data according to the one-factor random effect model were assumed. Results: Analysis-of-variance (ANOVA)-based computation was applied to estimate the values and their confidence intervals (CIs) for systematic and random errors and the population mean of setup errors. The conventional method overestimates systematic error, especially in hypofractionated settings. The CI for systematic error becomes much wider than that for random error. The ANOVA-based estimation can be extended to a multifactor model considering multiplemore » causes of setup errors (e.g., interpatient, interfraction, and intrafraction). Conclusions: Variance component analysis may lead to novel applications to setup error analysis in radiotherapy.« less

  9. Phase I Study of Accelerated Conformal Radiotherapy for Stage I Non–Small-Cell Lung Cancer in Patients With Pulmonary Dysfunction: CALGB 39904

    PubMed Central

    Bogart, Jeffrey A.; Hodgson, Lydia; Seagren, Stephen L.; Blackstock, A. William; Wang, Xiaofei; Lenox, Robert; Turrisi, Andrew T.; Reilly, John; Gajra, Ajeet; Vokes, Everett E.; Green, Mark R.

    2010-01-01

    Purpose The optimal treatment for medically inoperable stage I non–small-cell lung cancer (NSCLC) has not been defined. Patients and Methods Cancer and Leukemia Group B trial 39904 prospectively assessed accelerated, once-daily, three-dimensional radiotherapy for early-stage NSCLC. The primary objectives were to define the maximally accelerated course of conformal radiotherapy and to describe the short-term and long-term toxicity of therapy. Entry was limited to patients with clinical stage T1N0 or T2N0 NSCLC (< 4 cm) and pulmonary dysfunction. The nominal total radiotherapy dose remained at 70 Gy, while the number of daily fractions in each successive cohort was reduced. Results Thirty-nine eligible patients were accrued (eight patients each on cohorts 1 to 4 and seven patients on cohort 5) between January 2001 and July 2005. One grade 3 nonhematologic toxicity was observed in both cohort 3 (dyspnea) and cohort 4 (pain). The major response rate was 77%. After a median follow-up time of 53 months, the actuarial median survival time of all eligible patients was 38.5 months. Local relapse was observed in three patients. Conclusion Accelerated conformal radiotherapy was well tolerated in a high-risk population with clinical stage I NSCLC. Outcomes are comparable to prospective reports of alternative therapies, including stereotactic body radiation therapy and limited resection, with less apparent severe toxicity. Further investigation of this approach is warranted. PMID:19933904

  10. Outcome of accelerated radiotherapy alone or accelerated radiotherapy followed by exenteration of the nasal cavity in dogs with intranasal neoplasia: 53 cases (1990-2002).

    PubMed

    Adams, William M; Bjorling, Dale E; McAnulty, Jonathan E; Green, Eric M; Forrest, Lisa J; Vail, David M

    2005-09-15

    To compare long-term results of radiotherapy alone versus radiotherapy followed by exenteration of the nasal cavity in dogs with malignant intranasal neoplasia. Retrospective study. 53 dogs with malignant intranasal neoplasia. All dogs underwent radiotherapy consisting of administration of 10 fractions of 4.2 Gy each on consecutive weekdays. For dogs in the surgery group (n=13), follow-up computed tomography was performed, and dogs were scheduled for surgery if persistent or recurrent tumor was seen. Perioperative complications for dogs that underwent surgery included hemorrhage requiring transfusion (2 dogs) and subcutaneous emphysema (8). Rhinitis and osteomyelitis-osteonecrosis occurred significantly more frequently in dogs in the radiotherapy and surgery group (9 and 4 dogs, respectively) than in dogs in the radiotherapy-only group (4 and 3 dogs, respectively). Two- and 3-year survival rates were 44% and 24%, respectively, for dogs in the radiotherapy group and 69% and 58%, respectively, for dogs in the surgery group. Overall median survival time for dogs in the radiotherapy and surgery group (477 months) was significantly longer than time for dogs in the radiotherapy-only group (19.7 months). Results suggest that exenteration of the nasal cavity significantly prolongs survival time in dogs with intranasal neoplasia that have undergone radiotherapy. Exenteration after radiotherapy may increase the risk of chronic complications.

  11. The Impact of Radiation Oncologists on the Early Adoption of Hypofractionated Radiation Therapy for Early-Stage Breast Cancer.

    PubMed

    Boero, Isabel J; Gillespie, Erin F; Hou, Jiayi; Paravati, Anthony J; Kim, Ellen; Einck, John P; Yashar, Catheryn; Mell, Loren K; Murphy, James D

    2017-03-01

    Despite multiple randomized trials showing the efficacy of hypofractionated radiation therapy in early-stage breast cancer, the United States has been slow to adopt this treatment. The goal of this study was to evaluate the impact of individual radiation oncologists on the early adoption of hypofractionated radiation therapy for early-stage breast cancer. We identified 22,233 Medicare beneficiaries with localized breast cancer that was diagnosed from 2004 to 2011 who underwent breast-conserving surgery with adjuvant radiation. Multilevel, multivariable logistic models clustered by radiation oncologist and geographic practice area were used to determine the impact of the provider and geographic region on the likelihood of receiving hypofractionated compared with standard fractionated radiation therapy while controlling for a patient's clinical and demographic covariates. Odds ratios (OR) describe the impact of demographic or clinical covariates, and the median OR (MOR) describes the relative impact of the individual radiation oncologist and geographic region on the likelihood of undergoing hypofractionated radiation therapy. Among the entire cohort, 2333 women (10.4%) were treated with hypofractionated radiation therapy, with unadjusted rates ranging from 0.0% in the bottom quintile of radiation oncologists to 30.4% in the top quintile. Multivariable analysis found that the individual radiation oncologist (MOR 3.08) had a greater impact on the use of hypofractionation than did geographic region (MOR 2.10) or clinical and demographic variables. The impact of the provider increased from the year 2004 to 2005 (MOR 2.82) to the year 2010 to 2011 (MOR 3.16) despite the publication of long-term randomized trial results in early 2010. Male physician and radiation oncologists treating the highest volume of breast cancer patients were less likely to perform hypofractionation (P<.05). The individual radiation oncologist strongly influenced the likelihood of a patient

  12. MO-G-BRF-06: Radiotherapy and Prompt Oxygen Dynamics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kissick, M; Campos, D; Adamson, E

    Purpose: Adaptive radiotherapy requires a knowledge of the changing local tumor oxygen concentrations for times on the order of the treatment time, a time scale far shorter than cell death and proliferation. This knowledge will be needed to guide hypofractionated radiotherapy. Methods: A diffuse optical probe system was developed to spatially average over the whole interior of athymic Sprague Dawley nude mouse xenografts of human head and neck cancers. The blood volume and hemoglobin saturation was measured in real time. The quantities were measured with spectral fitting before and after 10 Gy of radiation is applied. An MRI BOLD scanmore » is acquired before and after 10 Gy that measures regional changes in R2* which is inversely proportional to oxygen availability. Simulations were performed to fit the blood oxygen dynamics and infer changes in hypoxia within the tumor. Results: The optical probe measured nearly constant blood volume and a significant drop in hemoglobin saturation of about 30% after 10 Gy over the time scale of less than 30 minutes. The averaged R2* within the tumor volume increased by 15% after the 10 Gy dose, which is consistent with the optical results. The simulations and experiments support likely dynamic metabolic changes and/or fast vasoconstrictive signals are occurring that change the oxygen concentrations significantly, but not cell death or proliferation. Conclusion: Significant oxygen changes were observed to occur within 30 minutes, coinciding with the treatment time scale. This dynamic is very important for patient specific adaptive therapy. For hypofractionated therapy, the local instantaneous oxygen content is likely the most important variable to control. The invention of a bedside device for the purpose of measuring the instantaneous response to large radiation doses would be an important step to future improvements in outcome.« less

  13. 11C choline PET guided salvage radiotherapy with volumetric modulation arc therapy and hypofractionation for recurrent prostate cancer after HIFU failure: preliminary results of tolerability and acute toxicity.

    PubMed

    Alongi, Filippo; Liardo, Rocco L E; Iftode, Cristina; Lopci, Egesta; Villa, Elisa; Comito, Tiziana; Tozzi, Angelo; Navarria, Pierina; Ascolese, Anna M; Mancosu, Pietro; Tomatis, Stefano; Bellorofonte, Carlo; Arturo, Chiti; Scorsetti, Marta

    2014-10-01

    The purpose of this work was to evaluate tolerance, feasibility and acute toxicity in patients undergoing salvage radiotherapy after high-intensity focused ultrasound (HIFU) failure. From 2005 to 2011 a total of 15 patients were treated with HIFU as primary radical treatment. Between July 2011 and February 2013, all 15 patients presented biochemical relapse after HIFU and 11C choline PET documenting intrapostatic-only failure. Salvage EBRT was performed with moderate hypofractionation schedule in 28 fractions with volumetric modulation arc therapy (VMAT). Genito-urinary (GU) and rectal and bowel toxicity were scored by common terminology criteria for adverse events version 4 (CTCAE V.4) scale. Biochemical response was assessed by ASTRO Phoenix criteria. Median age of patients was 67 years (range: 53-85). The median Gleason score was 7 (range: 6-9). The median prostate specific antigen (PSA) at the time of biochemical relapse after HIFU was 5.2 ng/mL (range: 2-64.2). Seven of the 15 patients received androgen deprivation therapy (ADT) started after HIFU failure, interrupted before 11C choline PET and radiotherapy. Median prescribed dose was 71.4 Gy (range: 71.4-74.2 Gy) in 28 fractions. No radiation related major upper gastrointestinal (GI), rectal and GU toxicity were experienced. GU, acute grade 1 and grade 2 toxicities were recorded in 7/15 and 4/15 respectively; bowel acute grade 1 and grade 2 toxicities in 4/15 and 1/15; rectal acute grade 1 and grade 2 toxicities in 3/15 and 2/15 respectively. No grade 3 or greater acute or late toxicities occurred. Biochemical control was assessed in 12/15 (80%) patients. With a median follow up of 12 months, three out of 15 patients, with biochemical relapse, showed lymph-nodal recurrence. Our early clinical results and biochemical data confirm the feasibility and show a good tolerance of the 11C choline PET guided salvage radiation therapy after HIFU failure. The findings of low acute toxicity is encouraging, but longer

  14. [Task sharing with radiotherapy technicians in image-guided radiotherapy].

    PubMed

    Diaz, O; Lorchel, F; Revault, C; Mornex, F

    2013-10-01

    The development of accelerators with on-board imaging systems now allows better target volumes reset at the time of irradiation (image-guided radiotherapy [IGRT]). However, these technological advances in the control of repositioning led to a multiplication of tasks for each actor in radiotherapy and increase the time available for the treatment, whether for radiotherapy technicians or radiation oncologists. As there is currently no explicit regulatory framework governing the use of IGRT, some institutional experiments show that a transfer is possible between radiation oncologists and radiotherapy technicians for on-line verification of image positioning. Initial training for every technical and drafting procedures within institutions will improve audit quality by reducing interindividual variability. Copyright © 2013. Published by Elsevier SAS.

  15. 4D radiobiological modelling of the interplay effect in conventionally and hypofractionated lung tumour IMRT.

    PubMed

    Selvaraj, J; Uzan, J; Baker, C; Nahum, A

    2015-01-01

    To study the impact of the interplay between respiration-induced tumour motion and multileaf collimator leaf movements in intensity-modulated radiotherapy (IMRT) as a function of number of fractions, dose rate on population mean tumour control probability ([Formula: see text]) using an in-house developed dose model. Delivered dose was accumulated in a voxel-by-voxel basis inclusive of tumour motion over the course of treatment. The effect of interplay on dose and [Formula: see text] was studied for conventionally and hypofractionated treatments using digital imaging and communications in medicine data sets. Moreover, the effect of dose rate on interplay was also studied for single-fraction treatments. Simulations were repeated several times to obtain [Formula: see text] for each plan. The average variation observed in mean dose to the target volumes were -0.76% ± 0.36% for the 20-fraction treatment and -0.26% ± 0.68% and -1.05% ± 0.98% for the three- and single-fraction treatments, respectively. For the 20-fraction treatment, the drop in [Formula: see text] was -1.05% ± 0.39%, whereas for the three- and single-fraction treatments, it was -2.80% ± 1.68% and -4.00% ± 2.84%, respectively. By reducing the dose rate from 600 to 300 MU min(-1) for the single-fraction treatments, the drop in [Formula: see text] was reduced by approximately 1.5%. The effect of interplay on [Formula: see text] is negligible for conventionally fractionated treatments, whereas considerable drop in [Formula: see text] is observed for the three- and single-fraction treatments. Reduced dose rate could be used in hypofractionated treatments to reduce the interplay effect. A novel in silico dose model is presented to determine the impact of interplay effect in IMRT treatments on [Formula: see text].

  16. 4D radiobiological modelling of the interplay effect in conventionally and hypofractionated lung tumour IMRT

    PubMed Central

    Uzan, J; Baker, C; Nahum, A

    2015-01-01

    Objective: To study the impact of the interplay between respiration-induced tumour motion and multileaf collimator leaf movements in intensity-modulated radiotherapy (IMRT) as a function of number of fractions, dose rate on population mean tumour control probability () using an in-house developed dose model. Methods: Delivered dose was accumulated in a voxel-by-voxel basis inclusive of tumour motion over the course of treatment. The effect of interplay on dose and was studied for conventionally and hypofractionated treatments using digital imaging and communications in medicine data sets. Moreover, the effect of dose rate on interplay was also studied for single-fraction treatments. Simulations were repeated several times to obtain for each plan. Results: The average variation observed in mean dose to the target volumes were −0.76% ± 0.36% for the 20-fraction treatment and −0.26% ± 0.68% and −1.05% ± 0.98% for the three- and single-fraction treatments, respectively. For the 20-fraction treatment, the drop in was −1.05% ± 0.39%, whereas for the three- and single-fraction treatments, it was −2.80% ± 1.68% and −4.00% ± 2.84%, respectively. By reducing the dose rate from 600 to 300 MU min−1 for the single-fraction treatments, the drop in was reduced by approximately 1.5%. Conclusion: The effect of interplay on is negligible for conventionally fractionated treatments, whereas considerable drop in is observed for the three- and single-fraction treatments. Reduced dose rate could be used in hypofractionated treatments to reduce the interplay effect. Advances in knowledge: A novel in silico dose model is presented to determine the impact of interplay effect in IMRT treatments on . PMID:25251400

  17. The Pattern of Use of Hypofractionated Radiation Therapy for Early-Stage Breast Cancer in New South Wales, Australia, 2008 to 2012

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Delaney, Geoff P., E-mail: Geoff.delaney@swsahs.nsw.gov.au; Collaboration for Cancer Outcomes Research and Evaluation, University of New South Wales, Sydney; Ingham Health and Medical Research Institute, Sydney

    Purpose: Increasing phase 3 evidence has been published about the safety and efficacy of hypofractionated radiation therapy, in comparison with standard fractionation, in early-stage, node-negative breast cancer. However, uptake of hypofractionation has not been universal. The aim of this study was to investigate the hypofractionation regimen variations in practice across public radiation oncology facilities in New South Wales (NSW). Methods and Materials: Patients with early breast cancer registered in the NSW Clinical Cancer Registry who received radiation therapy for early-stage breast cancer in a publicly funded radiation therapy department between 2008 and 2012 were identified. Data extracted and analyzed includedmore » dose and fractionation type, patient age at first fraction, address (for geocoding), year of diagnosis, year of treatment, laterality, and department of treatment. A logistic regression model was used to identify factors associated with fractionation type. Results: Of the 5880 patients fulfilling the study criteria, 3209 patients (55%) received standard fractionation and 2671 patients (45%) received hypofractionation. Overall, the use of hypofractionation increased from 37% in 2008 to 48% in 2012 (range, 7%-94% across departments). Treatment facility and the radiation oncologist prescribing the treatment were the strongest independent predictors of hypofractionation. Weaker associations were also found for age, tumor site laterality, year of treatment, and distance to facility. Conclusions: Hypofractionated regimens of whole breast radiation therapy have been variably administered in the adjuvant setting in NSW despite the publication of long-term trial results and consensus guidelines. Some factors that predict the use of hypofractionation are not based on guideline recommendations, including lower rates of left-sided treatment and increasing distance from a treatment facility.« less

  18. Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rasmussen, Rune, E-mail: rune333@gmail.com; Claesson, Magnus; Stangerup, Sven-Eric

    2012-08-01

    Objective: To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hearing preservation was also investigated. Methods and Materials: Forty-two patients receiving FSRT between 1997 and 2008 with a minimum follow-up of 2 years were included. All patients received 54 Gy in 27-30 fractions during 5.5-6.0 weeks. Clinical and audiometry data were collected prospectively. From a 'wait-and-scan' group, 409 patients were selected as control subjects, matched by initial audiometric parameters. Radiation dosemore » to the cochlea was measured using the original treatment plan and then related to changes in acoustic parameters. Results: Actuarial 2-, 4-, and 10-year tumor control rates were 100%, 91.5%, and 85.0%, respectively. Twenty-one patients had serviceable hearing before FSRT, 8 of whom (38%) retained serviceable hearing at 2 years after FSRT. No patients retained serviceable hearing after 10 years. At 2 years, hearing preservation rates in the control group were 1.8 times higher compared with the group receiving FSRT (P=.007). Radiation dose to the cochlea was significantly correlated to deterioration of the speech reception threshold (P=.03) but not to discrimination loss. Conclusion: FSRT accelerates the naturally occurring hearing loss in patients with vestibular schwannoma. Our findings, using fractionation of radiotherapy, parallel results using single-dose radiation. The radiation dose to the cochlea is correlated to hearing loss measured as the speech reception threshold.« less

  19. Big Data Analytics for Prostate Radiotherapy.

    PubMed

    Coates, James; Souhami, Luis; El Naqa, Issam

    2016-01-01

    Radiation therapy is a first-line treatment option for localized prostate cancer and radiation-induced normal tissue damage are often the main limiting factor for modern radiotherapy regimens. Conversely, under-dosing of target volumes in an attempt to spare adjacent healthy tissues limits the likelihood of achieving local, long-term control. Thus, the ability to generate personalized data-driven risk profiles for radiotherapy outcomes would provide valuable prognostic information to help guide both clinicians and patients alike. Big data applied to radiation oncology promises to deliver better understanding of outcomes by harvesting and integrating heterogeneous data types, including patient-specific clinical parameters, treatment-related dose-volume metrics, and biological risk factors. When taken together, such variables make up the basis for a multi-dimensional space (the "RadoncSpace") in which the presented modeling techniques search in order to identify significant predictors. Herein, we review outcome modeling and big data-mining techniques for both tumor control and radiotherapy-induced normal tissue effects. We apply many of the presented modeling approaches onto a cohort of hypofractionated prostate cancer patients taking into account different data types and a large heterogeneous mix of physical and biological parameters. Cross-validation techniques are also reviewed for the refinement of the proposed framework architecture and checking individual model performance. We conclude by considering advanced modeling techniques that borrow concepts from big data analytics, such as machine learning and artificial intelligence, before discussing the potential future impact of systems radiobiology approaches.

  20. Big Data Analytics for Prostate Radiotherapy

    PubMed Central

    Coates, James; Souhami, Luis; El Naqa, Issam

    2016-01-01

    Radiation therapy is a first-line treatment option for localized prostate cancer and radiation-induced normal tissue damage are often the main limiting factor for modern radiotherapy regimens. Conversely, under-dosing of target volumes in an attempt to spare adjacent healthy tissues limits the likelihood of achieving local, long-term control. Thus, the ability to generate personalized data-driven risk profiles for radiotherapy outcomes would provide valuable prognostic information to help guide both clinicians and patients alike. Big data applied to radiation oncology promises to deliver better understanding of outcomes by harvesting and integrating heterogeneous data types, including patient-specific clinical parameters, treatment-related dose–volume metrics, and biological risk factors. When taken together, such variables make up the basis for a multi-dimensional space (the “RadoncSpace”) in which the presented modeling techniques search in order to identify significant predictors. Herein, we review outcome modeling and big data-mining techniques for both tumor control and radiotherapy-induced normal tissue effects. We apply many of the presented modeling approaches onto a cohort of hypofractionated prostate cancer patients taking into account different data types and a large heterogeneous mix of physical and biological parameters. Cross-validation techniques are also reviewed for the refinement of the proposed framework architecture and checking individual model performance. We conclude by considering advanced modeling techniques that borrow concepts from big data analytics, such as machine learning and artificial intelligence, before discussing the potential future impact of systems radiobiology approaches. PMID:27379211

  1. Hippocampal-Sparing Whole-Brain Radiotherapy: A 'How-To' Technique Using Helical Tomotherapy and Linear Accelerator-Based Intensity-Modulated Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gondi, Vinai; Tolakanahalli, Ranjini; Mehta, Minesh P.

    2010-11-15

    Purpose: Sparing the hippocampus during cranial irradiation poses important technical challenges with respect to contouring and treatment planning. Herein we report our preliminary experience with whole-brain radiotherapy using hippocampal sparing for patients with brain metastases. Methods and Materials: Five anonymous patients previously treated with whole-brain radiotherapy with hippocampal sparing were reviewed. The hippocampus was contoured, and hippocampal avoidance regions were created using a 5-mm volumetric expansion around the hippocampus. Helical tomotherapy and linear accelerator (LINAC)-based intensity-modulated radiotherapy (IMRT) treatment plans were generated for a prescription dose of 30 Gy in 10 fractions. Results: On average, the hippocampal avoidance volume wasmore » 3.3 cm{sup 3}, occupying 2.1% of the whole-brain planned target volume. Helical tomotherapy spared the hippocampus, with a median dose of 5.5 Gy and maximum dose of 12.8 Gy. LINAC-based IMRT spared the hippocampus, with a median dose of 7.8 Gy and maximum dose of 15.3 Gy. On a per-fraction basis, mean dose to the hippocampus (normalized to 2-Gy fractions) was reduced by 87% to 0.49 Gy{sub 2} using helical tomotherapy and by 81% to 0.73 Gy{sub 2} using LINAC-based IMRT. Target coverage and homogeneity was acceptable with both IMRT modalities, with differences largely attributed to more rapid dose fall-off with helical tomotherapy. Conclusion: Modern IMRT techniques allow for sparing of the hippocampus with acceptable target coverage and homogeneity. Based on compelling preclinical evidence, a Phase II cooperative group trial has been developed to test the postulated neurocognitive benefit.« less

  2. Image Guided Hypofractionated Postprostatectomy Intensity Modulated Radiation Therapy for Prostate Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewis, Stephen L.; Patel, Pretesh; Song, Haijun

    2016-03-01

    Purpose: Hypofractionated radiation therapy (RT) has promising long-term biochemical relapse-free survival (bRFS) with comparable toxicity for definitive treatment of prostate cancer. However, data reporting outcomes after adjuvant and salvage postprostatectomy hypofractionated RT are sparse. Therefore, we report the toxicity and clinical outcomes after postprostatectomy hypofractionated RT. Methods and Materials: From a prospectively maintained database, men receiving image guided hypofractionated intensity modulated RT (HIMRT) with 2.5-Gy fractions constituted our study population. Androgen deprivation therapy was used at the discretion of the radiation oncologist. Acute toxicities were graded according to the Common Terminology Criteria for Adverse Events version 4.0. Late toxicities weremore » scored using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scale. Biochemical recurrence was defined as an increase of 0.1 in prostate-specific antigen (PSA) from posttreatment nadir or an increase in PSA despite treatment. The Kaplan-Meier method was used for the time-to-event outcomes. Results: Between April 2008 and April 2012, 56 men received postoperative HIMRT. The median follow-up time was 48 months (range, 21-67 months). Thirty percent had pre-RT PSA <0.1; the median pre-RT detectable PSA was 0.32 ng/mL. The median RT dose was 65 Gy (range, 57.5-65 Gy). Ten patients received neoadjuvant and concurrent hormone therapy. Posttreatment acute urinary toxicity was limited. There was no acute grade 3 toxicity. Late genitourinary (GU) toxicity of any grade was noted in 52% of patients, 40% of whom had pre-RT urinary incontinence. The 4-year actuarial rate of late grade 3 GU toxicity (exclusively gross hematuria) was 28% (95% confidence interval [CI], 16%-41%). Most grade 3 GU toxicity resolved; only 7% had persistent grade ≥3 toxicity at the last follow-up visit. Fourteen patients experienced biochemical

  3. Rectal Bleeding After High-Dose-Rate Brachytherapy Combined With Hypofractionated External-Beam Radiotherapy for Localized Prostate Cancer: The Relationship Between Dose-Volume Histogram Parameters and the Occurrence Rate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Okamoto, Masahiko, E-mail: masaoka@showa.gunma-u.ac.jp; Ishikawa, Hitoshi; Ebara, Takeshi

    2012-02-01

    Purpose: To determine the predictive risk factors for Grade 2 or worse rectal bleeding after high-dose-rate brachytherapy (HDR-BT) combined with hypofractionated external-beam radiotherapy (EBRT) for prostate cancer using dose-volume histogram analysis. Methods and Materials: The records of 216 patients treated with HDR-BT combined with EBRT were analyzed. The treatment protocols for HDR-BT were 5 Gy Multiplication-Sign five times in 3 days or 7 Gy Multiplication-Sign three, 10.5 Gy Multiplication-Sign two, or 9 Gy Multiplication-Sign two in 2 days. The EBRT doses ranged from 45 to 51 Gy with a fractional dose of 3 Gy. Results: In 20 patients Grade 2more » or worse rectal bleeding developed, and the cumulative incidence rate was 9% at 5 years. By converting the HDR-BT and EBRT radiation doses into biologic effective doses (BED), the BED{sub 3} at rectal volumes of 5% and 10% in the patients who experienced bleeding were significantly higher than those in the remaining 196 patients. Univariate analysis showed that a higher rectal BED{sub 3-5%} and the use of fewer needles in brachytherapy were correlated with the incidence of bleeding, but BED{sub 3-5%} was found to be the only significant factor on multivariate analysis. Conclusions: The radiation dose delivered to small rectal lesions as 5% is important for predicting Grade 2 or worse rectal bleeding after HDR-BT combined with EBRT for prostate cancer.« less

  4. Hypofractionated whole breast radiation and partial breast radiation for early-stage breast cancers: an update on progress.

    PubMed

    McCormick, Beryl

    2012-09-01

    This article provides an update of recent progress using partial breast irradiation (PBI) for the treatment of early-stage breast cancer, rather than whole breast radiotherapy (WBRT), which is the standard of care. Several large, prospective, randomized trials are nearing target accrual or have been completed, including the NSABP/RTOG trial, the Milan-based intraoperative radiation trial, and the international TARGIT trial, and the status of each is discussed. The American Society for Radiation Oncology has also published a consensus statement to guide the use of PBI until some of the phase III trials are more mature. Finally, several articles have appeared recently, reporting unexpected adverse effects of PBI in small series, and this information is reviewed. Several recent prospective trials of WBRT are also discussed, with the theme of comparing the standard 25 fractions to a shortened, hypofractionated trial arm delivering equivalent doses of WBRT in approximately 15 treatments, another radiation strategy for a shortened course of treatment after breast-conserving surgery.

  5. Radiotherapy and "new" drugs-new side effects?

    PubMed Central

    2011-01-01

    Background and purpose Targeted drugs have augmented the cancer treatment armamentarium. Based on the molecular specificity, it was initially believed that these drugs had significantly less side effects. However, currently it is accepted that all of these agents have their specific side effects. Based on the given multimodal approach, special emphasis has to be placed on putative interactions of conventional cytostatic drugs, targeted agents and other modalities. The interaction of targeted drugs with radiation harbours special risks, since the awareness for interactions and even synergistic toxicities is lacking. At present, only limited is data available regarding combinations of targeted drugs and radiotherapy. This review gives an overview on the current knowledge on such combined treatments. Materials and methods Using the following MESH headings and combinations of these terms pubmed database was searched: Radiotherapy AND cetuximab/trastuzumab/panitumumab/nimotuzumab, bevacizumab, sunitinib/sorafenib/lapatinib/gefitinib/erlotinib/sirolimus, thalidomide/lenalidomide as well as erythropoietin. For citation crosscheck the ISI web of science database was used employing the same search terms. Results Several classes of targeted substances may be distinguished: Small molecules including kinase inhibitors and specific inhibitors, antibodies, and anti-angiogenic agents. Combination of these agents with radiotherapy may lead to specific toxicities or negatively influence the efficacy of RT. Though there is only little information on the interaction of molecular targeted radiation and radiotherapy in clinical settings, several critical incidents are reported. Conclusions The addition of molecular targeted drugs to conventional radiotherapy outside of approved regimens or clinical trials warrants a careful consideration especially when used in conjunction in hypo-fractionated regimens. Clinical trials are urgently needed in order to address the open question in regard

  6. Dose-Fractionation Sensitivity of Prostate Cancer Deduced From Radiotherapy Outcomes of 5,969 Patients in Seven International Institutional Datasets: {alpha}/{beta} = 1.4 (0.9-2.2) Gy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miralbell, Raymond, E-mail: Raymond.Miralbell@hcuge.ch; Institut Oncologic Teknon, Barcelona; Roberts, Stephen A.

    2012-01-01

    Purpose: There are reports of a high sensitivity of prostate cancer to radiotherapy dose fractionation, and this has prompted several trials of hypofractionation schedules. It remains unclear whether hypofractionation will provide a significant therapeutic benefit in the treatment of prostate cancer, and whether there are different fractionation sensitivities for different stages of disease. In order to address this, multiple primary datasets have been collected for analysis. Methods and Materials: Seven datasets were assembled from institutions worldwide. A total of 5969 patients were treated using external beams with or without androgen deprivation (AD). Standard fractionation (1.8-2.0 Gy per fraction) was usedmore » for 40% of the patients, and hypofractionation (2.5-6.7 Gy per fraction) for the remainder. The overall treatment time ranged from 1 to 8 weeks. Low-risk patients comprised 23% of the total, intermediate-risk 44%, and high-risk 33%. Direct analysis of the primary data for tumor control at 5 years was undertaken, using the Phoenix criterion of biochemical relapse-free survival, in order to calculate values in the linear-quadratic equation of k (natural log of the effective target cell number), {alpha} (dose-response slope using very low doses per fraction), and the ratio {alpha}/{beta} that characterizes dose-fractionation sensitivity. Results: There was no significant difference between the {alpha}/{beta} value for the three risk groups, and the value of {alpha}/{beta} for the pooled data was 1.4 (95% CI = 0.9-2.2) Gy. Androgen deprivation improved the bNED outcome index by about 5% for all risk groups, but did not affect the {alpha}/{beta} value. Conclusions: The overall {alpha}/{beta} value was consistently low, unaffected by AD deprivation, and lower than the appropriate values for late normal-tissue morbidity. Hence the fractionation sensitivity differential (tumor/normal tissue) favors the use of hypofractionated radiotherapy schedules for all

  7. Reproducibility of patient positioning for fractionated extracranial stereotactic radiotherapy using a double-vacuum technique.

    PubMed

    Nevinny-Stickel, Meinhard; Sweeney, Reinhart A; Bale, Reto J; Posch, Andrea; Auberger, Thomas; Lukas, Peter

    2004-02-01

    Precise reproducible patient positioning is a prerequisite for conformal fractionated radiotherapy. A fixation system based on double-vacuum technology is presented which can be used for conventional as well as hypofractionated stereotactic extracranial radiotherapy. To form the actual vacuum mattress, the patient is pressed into the mattress with a vacuum foil which can also be used for daily repositioning and fixation. A stereotactic frame can be positioned over the region of interest on an indexed base plate. Repositioning accuracy was determined by comparing daily, pretreatment, orthogonal portal images to the respective digitally reconstructed radiographs (DRRs) in ten patients with abdominal and pelvic lesions receiving extracranial fractionated (stereotactic) radiotherapy. The three-dimensional (3-D) vectors and 95% confidence intervals (CI) were calculated from the respective deviations in the three axes. Time required for initial mold production and daily repositioning was also determined. The mean 3-D repositioning error (187 fractions) was 2.5 +/- 1.1 mm. The largest single deviation (10 mm) was observed in a patient treated in prone position. Mold production took an average of 15 min (10-30 min). Repositioning times are not necessarily longer than using no positioning aid at all. The presented fixation system allows reliable, flexible and efficient patient positioning for extracranial stereotactic radiotherapy.

  8. Cobalt-60 Machines and Medical Linear Accelerators: Competing Technologies for External Beam Radiotherapy.

    PubMed

    Healy, B J; van der Merwe, D; Christaki, K E; Meghzifene, A

    2017-02-01

    Medical linear accelerators (linacs) and cobalt-60 machines are both mature technologies for external beam radiotherapy. A comparison is made between these two technologies in terms of infrastructure and maintenance, dosimetry, shielding requirements, staffing, costs, security, patient throughput and clinical use. Infrastructure and maintenance are more demanding for linacs due to the complex electric componentry. In dosimetry, a higher beam energy, modulated dose rate and smaller focal spot size mean that it is easier to create an optimised treatment with a linac for conformal dose coverage of the tumour while sparing healthy organs at risk. In shielding, the requirements for a concrete bunker are similar for cobalt-60 machines and linacs but extra shielding and protection from neutrons are required for linacs. Staffing levels can be higher for linacs and more staff training is required for linacs. Life cycle costs are higher for linacs, especially multi-energy linacs. Security is more complex for cobalt-60 machines because of the high activity radioactive source. Patient throughput can be affected by source decay for cobalt-60 machines but poor maintenance and breakdowns can severely affect patient throughput for linacs. In clinical use, more complex treatment techniques are easier to achieve with linacs, and the availability of electron beams on high-energy linacs can be useful for certain treatments. In summary, there is no simple answer to the question of the choice of either cobalt-60 machines or linacs for radiotherapy in low- and middle-income countries. In fact a radiotherapy department with a combination of technologies, including orthovoltage X-ray units, may be an option. Local needs, conditions and resources will have to be factored into any decision on technology taking into account the characteristics of both forms of teletherapy, with the primary goal being the sustainability of the radiotherapy service over the useful lifetime of the equipment

  9. Radiation dose escalation by simultaneous modulated accelerated radiotherapy combined with chemotherapy for esophageal cancer: a phase II study.

    PubMed

    Chen, Jianzhou; Guo, Hong; Zhai, Tiantian; Chang, Daniel; Chen, Zhijian; Huang, Ruihong; Zhang, Wuzhe; Lin, Kun; Guo, Longjia; Zhou, Mingzhen; Li, Dongsheng; Li, Derui; Chen, Chuangzhen

    2016-04-19

    The outcomes for patients with esophageal cancer (EC) underwent standard-dose radical radiotherapy were still disappointing. This phase II study investigated the feasibility, safety and efficacy of radiation dose escalation using simultaneous modulated accelerated radiotherapy (SMART) combined with chemotherapy in 60 EC patients. Radiotherapy consisted of 66Gy at 2.2 Gy/fraction to the gross tumor and 54Gy at 1.8 Gy/fraction to subclinical diseases simultaneously. Chemotherapy including cisplatin and 5fluorouracil were administered to all patients during and after radiotherapy. The data showed that the majority of patients (98.3%) completed the whole course of radiotherapy and concurrent chemotherapy. The most common ≥ grade 3 acute toxicities were neutropenia (16.7%), followed by esophagitis (6.7%) and thrombopenia (5.0%). With a median follow-up of 24 months (5-38) for all patients and 30 months (18-38) for those still alive, 11 patients (18.3%) developed ≥ Grade 3 late toxicities and 2 (3.3%) of them died subsequently due to esophageal hemorrhage. The 1- and 2-year local-regional control, distant metastasis-free survival, disease-free survival and overall survival rates were 87.6% and 78.6%, 86.0% and 80.5%, 75.6% and 64.4%, 86.7% and 72.7%, respectively. SMART combined with concurrent chemotherapy is feasible in EC patients with tolerable acute toxicities. They showed a trend of significant improvements in local-regional control and overall survival. Further follow-up is needed to evaluate the late toxicities.

  10. Comparison between infrared optical and stereoscopic X-ray technologies for patient setup in image guided stereotactic radiotherapy.

    PubMed

    Tagaste, Barbara; Riboldi, Marco; Spadea, Maria F; Bellante, Simone; Baroni, Guido; Cambria, Raffaella; Garibaldi, Cristina; Ciocca, Mario; Catalano, Gianpiero; Alterio, Daniela; Orecchia, Roberto

    2012-04-01

    To compare infrared (IR) optical vs. stereoscopic X-ray technologies for patient setup in image-guided stereotactic radiotherapy. Retrospective data analysis of 233 fractions in 127 patients treated with hypofractionated stereotactic radiotherapy was performed. Patient setup at the linear accelerator was carried out by means of combined IR optical localization and stereoscopic X-ray image fusion in 6 degrees of freedom (6D). Data were analyzed to evaluate the geometric and dosimetric discrepancy between the two patient setup strategies. Differences between IR optical localization and 6D X-ray image fusion parameters were on average within the expected localization accuracy, as limited by CT image resolution (3 mm). A disagreement between the two systems below 1 mm in all directions was measured in patients treated for cranial tumors. In extracranial sites, larger discrepancies and higher variability were observed as a function of the initial patient alignment. The compensation of IR-detected rotational errors resulted in a significantly improved agreement with 6D X-ray image fusion. On the basis of the bony anatomy registrations, the measured differences were found not to be sensitive to patient breathing. The related dosimetric analysis showed that IR-based patient setup caused limited variations in three cases, with 7% maximum dose reduction in the clinical target volume and no dose increase in organs at risk. In conclusion, patient setup driven by IR external surrogates localization in 6D featured comparable accuracy with respect to procedures based on stereoscopic X-ray imaging. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Hypofractionation vs Conventional Radiation Therapy for Newly Diagnosed Diffuse Intrinsic Pontine Glioma: A Matched-Cohort Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Janssens, Geert O., E-mail: g.janssens@rther.umcn.nl; Jansen, Marc H.; Lauwers, Selmer J.

    2013-02-01

    Purpose: Despite conventional radiation therapy, 54 Gy in single doses of 1.8 Gy (54/1.8 Gy) over 6 weeks, most children with diffuse intrinsic pontine glioma (DIPG) will die within 1 year after diagnosis. To reduce patient burden, we investigated the role of hypofractionation radiation therapy given over 3 to 4 weeks. A 1:1 matched-cohort analysis with conventional radiation therapy was performed to assess response and survival. Methods and Materials: Twenty-seven children, aged 3 to 14, were treated according to 1 of 2 hypofractionation regimens over 3 to 4 weeks (39/3 Gy, n=16 or 44.8/2.8 Gy, n=11). All patients had symptomsmore » for {<=}3 months, {>=}2 signs of the neurologic triad (cranial nerve deficit, ataxia, long tract signs), and characteristic features of DIPG on magnetic resonance imaging. Twenty-seven patients fulfilling the same diagnostic criteria and receiving at least 50/1.8 to 2.0 Gy were eligible for the matched-cohort analysis. Results: With hypofractionation radiation therapy, the overall survival at 6, 9, and 12 months was 74%, 44%, and 22%, respectively. Progression-free survival at 3, 6, and 9 months was 77%, 43%, and 12%, respectively. Temporary discontinuation of steroids was observed in 21 of 27 (78%) patients. No significant difference in median overall survival (9.0 vs 9.4 months; P=.84) and time to progression (5.0 vs 7.6 months; P=.24) was observed between hypofractionation vs conventional radiation therapy, respectively. Conclusions: For patients with newly diagnosed DIPG, a hypofractionation regimen, given over 3 to 4 weeks, offers equal overall survival with less treatment burden compared with a conventional regimen of 6 weeks.« less

  12. WE-D-BRE-02: BEST IN PHYSICS (THERAPY) - Radiogenomic Modeling of Normal Tissue Toxicities in Prostate Cancer Patients Receiving Hypofractionated Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Coates, J; Jeyaseelan, K; Ybarra, N

    2014-06-15

    Purpose: It has been realized that inter-patient radiation sensitivity variability is a multifactorial process involving dosimetric, clinical, and genetic factors. Therefore, we explore a new framework to integrate physical, clinical, and biological data denoted as radiogenomic modeling. In demonstrating the feasibility of this work, we investigate the association of genetic variants (copy number variations [CNVs] and single nucleotide polymorphisms [SNPs]) with radiation induced rectal bleeding (RB) and erectile dysfunction (ED) while taking into account dosimetric and clinical variables in prostate cancer patients treated with curative irradiation. Methods: A cohort of 62 prostate cancer patients who underwent hypofractionated radiotherapy (66 Gymore » in 22 fractions) was retrospectively genotyped for CNV and SNP rs25489 in the xrcc1 DNA repair gene. Dosevolume metrics were extracted from treatment plans of 54 patients who had complete dosimetric profiles. Treatment outcomes were considered to be a Result of functional mapping of radiogenomic input variables according to a logit transformation. Model orders were estimated using resampling by leave-one out cross-validation (LOO-CV). Radiogenomic model performance was evaluated using area under the ROC curve (AUC) and LOO-CV. For continuous univariate dosimetric and clinical variables, Spearmans rank coefficients were calculated and p-values reported accordingly. In the case of binary variables, Chi-squared statistics and contingency table calculations were used. Results: Ten patients were found to have three copies of xrcc1 CNV (RB: χ2=14.6 [p<0.001] and ED: χ2=4.88[p=0.0272]) and twelve had heterozygous rs25489 SNP (RB: χ2=0.278[p=0.599] and ED: χ2=0.112[p=0.732]). LOO-CV identified penile bulb D60 as the only significant QUANTEC predictor (rs=0.312 [p=0.0145]) for ED. Radiogenomic modeling yielded statistically significant, cross-validated NTCP models for RB (rs=0.243[p=0.0443], AUC=0.665) and ED (rs=0

  13. Comparison of Radiation-Induced Normal Lung Tissue Density Changes for Patients From Multiple Institutions Receiving Conventional or Hypofractionated Treatments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Diot, Quentin, E-mail: quentin.diot@ucdenver.edu; Marks, Lawrence B.; Bentzen, Soren M.

    Purpose: To quantitatively assess changes in computed tomography (CT)–defined normal lung tissue density after conventional and hypofractionated radiation therapy (RT). Methods and Materials: The pre-RT and post-RT CT scans from 118 and 111 patients receiving conventional and hypofractionated RT, respectively, at 3 institutions were registered to each other and to the 3-dimensional dose distribution to quantify dose-dependent changes in normal lung tissue density. Dose-response curves (DRC) for groups of patients receiving conventional and hypofractionated RT were generated for each institution, and the frequency of density changes >80 Hounsfield Units (HU) was modeled depending on the fractionation type using a Probitmore » model for different follow-up times. Results: For the pooled data from all institutions, there were significant differences in the DRC between the conventional and hypofractionated groups; the respective doses resulting in 50% complication risk (TD{sub 50}) were 62 Gy (95% confidence interval [CI] 57-67) versus 36 Gy (CI 33-39) at <6 months, 48 Gy (CI 46-51) versus 31 Gy (CI 28-33) at 6-12 months, and 47 Gy (CI 45-49) versus 35 Gy (32-37) at >12 months. The corresponding m values (slope of the DRC) were 0.52 (CI 0.46-0.59) versus 0.31 (CI 0.28-0.34) at <6 months, 0.46 (CI 0.42-0.51) versus 0.30 (CI 0.26-0.34) at 6-12 months, and 0.45 (CI 0.42-0.50) versus 0.31 (CI 0.27-0.35) at >12 months (P<.05 for all comparisons). Conclusion: Compared with conventional fractionation, hypofractionation has a lower TD{sub 50} and m value, both suggesting an increased degree of normal tissue density sensitivity with hypofractionation.« less

  14. Radiotherapy using a laser proton accelerator

    NASA Astrophysics Data System (ADS)

    Murakami, Masao; Hishikawa, Yoshio; Miyajima, Satoshi; Okazaki, Yoshiko; Sutherland, Kenneth L.; Abe, Mitsuyuki; Bulanov, Sergei V.; Daido, Hiroyuki; Esirkepov, Timur Zh.; Koga, James; Yamagiwa, Mitsuru; Tajima, Toshiki

    2008-06-01

    Laser acceleration promises innovation in particle beam therapy of cancer where an ultra-compact accelerator system for cancer beam therapy can become affordable to a broad range of patients. This is not feasible without the introduction of a technology that is radically different from the conventional accelerator-based approach. Because of its compactness and other novel characteristics, the laser acceleration method provides many enhanced capabilities

  15. Influence of (11)C-choline PET/CT on radiotherapy planning in prostate cancer.

    PubMed

    López, Escarlata; Lazo, Antonio; Gutiérrez, Antonio; Arregui, Gregorio; Núñez, Isabel; Sacchetti, Antonio

    2015-01-01

    To evaluate the influence of (11)C-choline PET/CT on radiotherapy planning in prostate cancer patients. Precise information on the extension of prostate cancer is crucial for the choice of an appropriate therapeutic strategy. (11)C-choline positron emission tomography ((11)C-choline PET/CT) has two roles in radiation oncology (RT): (1) patient selection for treatment and (2) target volume selection and delineation. In conjunction with high-accuracy techniques, it might offer an opportunity of dose escalation and better tumour control while sparing healthy tissues. We carried out a retrospective study in order to analyse RT planning modification based on (11)C-choline PET/CT in 16 prostate cancer patients. Patients were treated with hypofractionated step-and-shoot Intensity Modulated Radiotherapy (IMRT), or Volumetric Modulated Arc Therapy (VMAT), and a daily cone-beam CT for Image Guided Radiation Therapy (IGRT). All patients underwent a (11)C-choline-PET/CT scan prior to radiotherapy. In 37.5% of cases, a re-delineation and new dose prescription occurred. Data show good preliminary clinical results in terms of biochemical control and toxicity. No gastrointestinal (GI)/genitourinary (GU) grade III toxicities were observed after a median follow-up of 9.5 months. In our experience, concerning the treatment of prostate cancer (PCa), (11)C-choline PET/CT may be helpful in radiotherapy planning, either for dose escalation or exclusion of selected sites.

  16. Accelerated superfractionated radiotherapy for inflammatory breast carcinoma: complete response predicts outcome and allows for breast conservation.

    PubMed

    Arthur, D W; Schmidt-Ullrich, R K; Friedman, R B; Wazer, D E; Kachnic, L A; Amir, C; Bear, H D; Hackney, M H; Smith, T J; Lawrence, W

    1999-05-01

    Chemotherapy and accelerated superfractionated radiotherapy were prospectively applied for inflammatory breast carcinoma with the intent of breast conservation. The efficacy, failure patterns, and patient tolerance utilizing this approach were analyzed. Between 1983 and 1996, 52 patients with inflammatory breast carcinoma presented to the Medical College of Virginia Hospitals of VCU and the New England Medical Center. Thirty-eight of these patients were jointly evaluated in multidisciplinary breast clinics and managed according to a defined prospectively applied treatment policy. Patients received induction chemotherapy, accelerated superfractionated radiotherapy, selected use of mastectomy, and concluded with additional chemotherapy. The majority were treated with 1.5 Gy twice daily to field arrangements covering the entire breast and regional lymphatics. An additional 18-21 Gy was then delivered to the breast and clinically involved nodal regions. Total dose to clinically involved areas was 63-66 Gy. Following chemoradiotherapy, patients were evaluated with physical examination, mammogram, and fine needle aspiration x 3. Mastectomy was reserved for those patients with evidence of persistent or progressive disease in the involved breast. All patients received additional chemotherapy. Median age was 51 years. Median follow-up was 23.9 months (6-86) months. The breast preservation rate at the time of last follow-up was 74%. The treated breast or chest wall as the first site of failure occurred in only 13%, and the ultimate local control rate with the selected use of mastectomy was 74%. Ten patients underwent mastectomy, 2 of which had pathologically negative specimens despite a clinically palpable residual mass. Response to chemotherapy was predictive of treatment outcome. Of the 15 patients achieving a complete response, 87% remain locoregionally controlled without the use of mastectomy. Five-year overall survival for complete responders was 68%. This is in

  17. Partial breast radiotherapy with simple teletherapy techniques.

    PubMed

    Fekete, Gábor; Újhidy, Dóra; Együd, Zsófia; Kiscsatári, Laura; Marosi, Gusztáv; Kahán, Zsuzsanna; Varga, Zoltán

    2015-01-01

    A prospective pilot study of partial breast irradiation (PBI) with conventional vs hypofractionated schedules was set out. The study aimed to determine efficacy, acute and late side effects, and the preference of photon vs electron irradiation based on individual features. Patients were enrolled according to internationally accepted guidelines on PBI. Conformal radiotherapy plans were generated with both photon and electron beams, and the preferred technique based on dose homogeneity and the radiation exposure of healthy tissues was applied. For electron dose verification, a special phantom was constructed. Patients were randomized for fractionation schedules of 25 × 2 vs 13 × 3Gy. Skin and breast changes were registered at the time of and ≥1 year after the completion of radiotherapy. Dose homogeneity was better with photons. If the tumor bed was located in the inner quadrants, electron beam gave superior results regarding conformity and sparing of organ at risk (OAR). If the tumor was situated in the lateral quadrants, conformity was better with photons. A depth of the tumor bed ≥3.0cm predicted the superiority of photon irradiation (odds ratio [OR] = 23.6, 95% CI: 5.2 to 107.5, p < 0.001) with >90% sensitivity and specificity. After a median follow-up of 39 months, among 72 irradiated cases, 1 local relapse out of the tumor bed was detected. Acute radiodermatitis of grade I to II, hyperpigmentation, and telangiectasia developed ≥1 year after radiotherapy, exclusively after electron beam radiotherapy. The choice of electrons or photons for PBI should be based on tumor bed location; the used methods are efficient and feasible. Copyright © 2015 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  18. Chest wall toxicity after hypofractionated proton beam therapy for liver malignancies.

    PubMed

    Yeung, Rosanna; Bowen, Stephen R; Chapman, Tobias R; MacLennan, Grayden T; Apisarnthanarax, Smith

    2017-12-24

    Normal liver-sparing with proton beam therapy (PBT) allows for dose escalation in the treatment of liver malignancies, but it may result in high doses to the chest wall (CW). CW toxicity (CWT) data after PBT for liver malignancies are limited, with most published reports describing toxicity after a combination of hypofractionated proton and photon radiation therapy. We examined the incidence and associated factors for CWT after hypofractionated PBT for liver malignancies. We retrospectively reviewed the charts of 37 consecutive patients with liver malignancies (30 hepatocellular carcinoma, 6 intrahepatic cholangiocarcinoma, and 1 metastasis) treated with hypofractionated PBT. CWT was scored using Common Terminology Criteria for Adverse Events, version 4. Receiver-operating characteristic curves were used to identify patient and dosimetric factors associated with CWT and to determine optimal dose-volume histogram parameters/cutoffs. Cox regression univariate analysis was used to associate factors to time-dependent onset of CWT. Thirty-nine liver lesions were treated with a median dose of 60 GyE (range, 35-67.5) in 15 fractions (range, 13-20). Median follow-up was 11 months (range, 2-44). Grade ≥2 and 3 CW pain occurred in 7 (19%) and 4 (11%) patients, respectively. Median time to onset of pain was 6 months (range, 1-14). No patients had radiographic rib fracture. On univariate analysis, CW equivalent 2 Gy dose with an α/β = 3 Gy (EQD2 α/β=3 ), V57 >20 cm 3 (hazard ratio [HR], 2.7; P = .004), V63 >17 cm 3 (HR, 2.7; P = .003), and V78 >8 cm 3 (HR, 2.6; P = .003) had the strongest association with grade ≥2 CW pain, as did tumor dose of >75 Gy EQD2 α/β=10 (HR, 8.7; P = .03). No other patient factors were associated with CWT. CWT after hypofractionated PBT for liver malignancies is clinically relevant. For a 15-fraction regimen, V47 >20 cm 3 , V50 >17 cm 3 , and V58 >8 cm 3 were associated with higher rates of CWT. Further investigation of PBT techniques to

  19. Patient-reported urinary incontinence after radiotherapy for prostate cancer: Quantifying the dose-effect.

    PubMed

    Cozzarini, Cesare; Rancati, Tiziana; Palorini, Federica; Avuzzi, Barbara; Garibaldi, Elisabetta; Balestrini, Damiano; Cante, Domenico; Munoz, Fernando; Franco, Pierfrancesco; Girelli, Giuseppe; Sini, Carla; Vavassori, Vittorio; Valdagni, Riccardo; Fiorino, Claudio

    2017-10-01

    Urinary incontinence following radiotherapy (RT) for prostate cancer (PCa) has a relevant impact on patient's quality of life. The aim of the study was to assess the unknown dose-effect relationship for late patient-reported urinary incontinence (LPRUI). Patients were enrolled within the multi-centric study DUE01. Clinical and dosimetry data including the prescribed 2Gy equivalent dose (EQD2) were prospectively collected. LPRUI was evaluated through the ICIQ-SF questionnaire filled in by the patients at RT start/end and therefore every 6months. Patients were treated with conventional (74-80Gy, 1.8-2Gy/fr) or moderately hypo-fractionated RT (65-75.2Gy, 2.2-2.7Gy/fr) in 5 fractions/week with intensity-modulated radiotherapy. Six different end-points of 3-year LPRUI, including or not patient's perception (respectively, subjective and objective end-points), were considered. Multivariable logistic models were developed for each end-point. Data of 298 patients were analyzed. The incidence of the most severe end-point (ICIQ-SF>12) was 5.1%. EQD2 calculated with alpha-beta=0.8Gy showed the best performance in fitting data: the risk of LPRUI markedly increased for EQD2>80Gy. Previous abdominal/pelvic surgery and previous TURP were the clinical factors more significantly predictive of LPRUI. Models showed excellent performances in terms of goodness-of-fit and calibration, confirmed by bootstrap-based internal validation. When included in the analyses, baseline symptoms were a major predictor for 5 out of six end-points. LPRUI after RT for PCa dramatically depends on EQD2 and few clinical factors. Results are consistent with a larger than expected impact of moderate hypo-fractionation on the risk of LPRUI. As expected, baseline symptoms, as captured by ICIQ-SF, are associated to an increased risk of LPRUI. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Low-dose radiosurgery or hypofractionated stereotactic radiotherapy as treatment option in refractory epilepsy due to epileptogenic lesions in eloquent areas - Preliminary report of feasibility and safety.

    PubMed

    Boström, Jan P; Delev, Daniel; Quesada, Carlos; Widman, Guido; Vatter, Hartmut; Elger, Christian E; Surges, Rainer

    2016-03-01

    The eradication of epileptogenic lesions (e.g. focal cortical dysplasia) can be used for treatment of drug-resistant focal epilepsy, but in highly eloquent cortex areas it can also lead to a permanent neurological deficit. In such cases the neuromodulation effect of low-dose high-precision irradiation of circumscribed lesions may represent an alternative therapy. A total of 10 patients with eloquent localized lesions causing pharmacoresistant focal epilepsy were prospectively identified. After informed consent, six patients agreed and were treated with risk adapted low-dose radiosurgery (SRS) or hypofractionated stereotactic radiotherapy (hfSRT). Comprehensive data concerning treatment modalities and outcome after short-term follow up (mean=16.3 months) were prospectively collected and evaluated. From the six patients, two patients were treated with hfSRT (marginal dose 36 Gy) and four with SRS (marginal dose 13 Gy). Clinical target volume (CTV) ranged from 0.70 ccm to 4.32 ccm. The short-term follow-up ranged from 6 to 27 months. There were no side effects or neurological deficits after treatment. At last available follow-up two patients were seizure-free, one of them being off antiepileptic drugs. The seizure frequency improved in one and remained unchanged in three patients. Treatment of eloquent localized epileptogenic lesions by SRS and hfSRT showed no adverse events and an acceptable seizure outcome in this small prospective patient series. The relatively short-term follow-up comprises one of the study's drawbacks and therefore a longer follow-up should be awaited in order to evaluate the neuromodulation effect of the treatment. These preliminary results may however justify the initiation of a larger prospective trial investigating whether focused low-dose stereotactic irradiation could be an option for lesions in eloquent brain areas. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  1. A comparison between cobalt and linear accelerator-based treatment plans for conformal and intensity-modulated radiotherapy.

    PubMed

    Adams, E J; Warrington, A P

    2008-04-01

    The simplicity of cobalt units gives them the advantage of reduced maintenance, running costs and downtime when compared with linear accelerators. However, treatments carried out on such units are typically limited to simple techniques. This study has explored the use of cobalt beams for conformal and intensity-modulated radiotherapy (IMRT). Six patients, covering a range of treatment sites, were planned using both X-ray photons (6/10 MV) and cobalt-60 gamma rays (1.17 and 1.33 MeV). A range of conformal and IMRT techniques were considered, as appropriate. Conformal plans created using cobalt beams for small breast, meningioma and parotid cases were found to compare well with those created using X-ray photons. By using additional fields, acceptable conformal plans were also created for oesophagus and prostate cases. IMRT plans were found to be of comparable quality for meningioma, parotid and thyroid cases on the basis of dose-volume histogram analysis. We conclude that it is possible to plan high-quality radical radiotherapy treatments for cobalt units. A well-designed beam blocking/compensation system would be required to enable a practical and efficient alternative to multileaf collimator (MLC)-based linac treatments to be offered. If cobalt units were to have such features incorporated into them, they could offer considerable benefits to the radiotherapy community.

  2. Hypofractionated IMRT of the Prostate Bed After Radical Prostatectomy: Acute Toxicity in the PRIAMOS-1 Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Katayama, Sonja, E-mail: sonja.katayama@med.uni-heidelberg.de; Striecker, Thorbjoern; Kessel, Kerstin

    Purpose: Hypofractionated radiation therapy as primary treatment for prostate cancer is currently being investigated in large phase 3 trials. However, there are few data on postoperative hypofractionation. The Radiation therapy for the Prostate Bed With or Without the Pelvic Lymph Nodes (PRIAMOS 1) trial was initiated as a prospective phase 2 trial to assess treatment safety and toxicity of a hypofractionated intensity modulated radiation therapy (IMRT) of the prostate bed. Methods and Materials: From February to September 2012, 40 patients with indications for adjuvant or salvage radiation therapy were enrolled. One patient dropped out before treatment. Patients received 54 Gy inmore » 18 fractions to the prostate bed with IMRT and daily image guidance. Gastrointestinal (GI) and genitourinary (GU) toxicities (according to National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0) were recorded weekly during treatment and 10 weeks after radiation therapy. Results: Overall acute toxicity was favorable, with no recorded adverse events grade ≥3. Acute GI toxicity rates were 56.4% (grade 1) and 17.9% (grade 2). Acute GU toxicity was recorded in 35.9% of patients (maximum grade 1). Urinary stress incontinence was not influenced by radiation therapy. The incidence of grade 1 urinary urge incontinence increased from 2.6% before to 23.1% 10 weeks after therapy, but grade 2 urge incontinence remained unchanged. Conclusions: Postoperative hypofractionated IMRT of the prostate bed is tolerated well, with no severe acute side effects.« less

  3. Feasibility and efficacy of helical intensity-modulated radiotherapy for stage III non-small cell lung cancer in comparison with conventionally fractionated 3D-CRT.

    PubMed

    He, Jian; Huang, Yan; Chen, Yixing; Shi, Shiming; Ye, Luxi; Hu, Yong; Zhang, Jianying; Zeng, Zhaochong

    2016-05-01

    The standard treatment for stage III non-small-cell lung cancer (NSCLC) is still 60 Gy in conventional fractions combined with concurrent chemotherapy; however, the resulting local controls are disappointing. The aim of this study was to compare and assess the feasibility and efficacy of hypofractionated chemoradiotherapy using helical tomotherapy (HT) with conventional fractionation as opposed to using three-dimensional conformal radiotherapy (3D-CRT) for stage III NSCLC. Sixty-nine patients with stage III (AJCC 7th edition) NSCLC who underwent definitive radiation treatment at our institution between July 2011 and November 2013 were reviewed and analyzed retrospectively. A dose of 60 Gy in 20 fractions was delivered in the HT group (n=34), whereas 60 Gy in 30 fractions in the 3D-CRT group (n=35). Primary endpoints were toxicity, overall response rate, overall survival (OS) and progression-free survival (PFS). The median follow-up period was 26.4 months. V20 (P=0.005), V30 (P=0.001), V40 (P=0.004), mean lung dose (P=0.000) and max dose of spinal cord (P=0.005) were significantly lower in the HT group than in the 3D-CRT group. There was no significant difference in the incidences of acute radiation pneumonitis (RP) ≥ grade 2 between the two groups, whereas the incidences of acute radiation esophagitis ≥ grade 2 were significantly lower in the HT group than in the 3D-CRT group (P=0.027). Two-year overall response rate was significantly higher in the HT group than in the 3D-CRT group (P=0.015). One- and 2-year OS rates were significantly higher in the HT group (95.0% and 68.7%, respectively) than in the 3D-CRT group (85.5% and 47.6%, respectively; P=0.0236). One- and 2-year PFS rates were significantly higher in the HT group (57.8% and 26.3%, respectively) than in the 3D-CRT group (32.7% and 11.4%, respectively; P=0.0351). Univariate analysis indicated that performance status (PS), T stage and radiotherapy technique were significant prognostic factors for both OS

  4. [Stereotactic radiotherapy and radiosurgery in treatment of patients with intracranial schwannomas].

    PubMed

    Zolotova, S V; Golanov, A V; Kotel'nikova, T M; Soboleva, O I; Gorlachev, G E; Fil'chenkova, N A; Nikonova, N G; Kapitanov, D N; Makhmudov, U B; Shimanskiĭ, V N; Arutiunov, N V; Pronin, I N

    2010-01-01

    Aim of this study is to assess the role of stereotactic radiosurgery (SRS) and radiotherapy (SRT) in management of cranial nerves schwannomas by analysis of tumor control, clinical response and variables affecting treatment outcomes. Between April 2005 and January 2009 patients with schwannomas of VIII (63), V (14) and caudal nerves (2) were treated in Burdenko Moscow Neurosurgical Institute using linear accelerator. Mean age was 49 years (13-82). In 42 cases radiation treatment was preceded by surgical resection. 13 patients had type I or II neurofibromatosis. Mean volume of the tumor was 3.9 cm3 (0.5-14.4 cm3) and 13.4 cm3 (2.8-41.3 cm3) for SRS and SRT, respectively. Mean SRS dose was 12 Gy (10.8-14.4 Gy) for vestibular schwannomas and 15 Gy (13.2-18 Gy) for schwannomas of other nerves. In hypofractionated SRT the dose of 35 Gy was delivered in 7 fractions or 30 Gy in 6 fractions. In cases of classical fractioning total dose of 50-60 Gy was divided into daily fractions of 1.8-2.0 Gy. Radiographic tumor control rate reached 97.5% at the last follow-up. 5 patients experienced trigeminal dysfunction, it was transient in 3 cases and persistent in 2. Permanent decline in House-Brackmann facial nerve scale developed in 2 of 79 patients. After treatment effective hearing (class I-II) was preserved in 7 of 9 patients (67%) who had same level of hearing before SRS. Linear accelerator-based stereotactic radiation treatment provides long-term tumor control associated with high rates of preservation of neurological functions. No further tumor surgery was necessary in 100% of cases with solitary tumors with a minimal follow-up of 5 years.

  5. Reporting combined outcomes with Trifecta and survival, continence, and potency (SCP) classification in 337 patients with prostate cancer treated with image-guided hypofractionated radiotherapy.

    PubMed

    Jereczek-Fossa, Barbara A; Zerini, Dario; Fodor, Cristiana; Santoro, Luigi; Maucieri, Andrea; Gerardi, Marianna A; Vischioni, Barbara; Cambria, Raffaella; Garibaldi, Cristina; Cattani, Federica; Vavassori, Andrea; Matei, Deliu V; Musi, Gennaro; De Cobelli, Ottavio; Orecchia, Roberto

    2014-12-01

    To report the image-guided hypofractionated radiotherapy (hypo-IGRT) outcome for patients with localised prostate cancer according to the new outcome models Trifecta (cancer control, urinary continence, and sexual potency) and SCP (failure-free survival, continence and potency). Between August 2006 and January 2011, 337 patients with cT1-T2N0M0 prostate cancer (median age 73 years) were eligible for a prospective longitudinal study on hypo-IGRT (70.2 Gy/26 fractions) in our Department. Patients completed four questionnaires before treatment, and during follow-up: the International Index of Erectile Function-5 (IIEF-5), the International Prostate Symptom Score (IPSS), and the European Organization for Research and Treatment of Cancer prostate-cancer-specific Quality of Life Questionnaires (QLQ) QLQ-PR25 and QLQ-C30. Baseline and follow-up patient data were analysed according to the Trifecta and SCP outcome models. Cancer control, continence and potency were defined respectively as no evidence of disease, score 1 or 2 for item 36 of the QLQ-PR25 questionnaire, and total score of >16 on the IIEF-5 questionnaire. Patients receiving androgen-deprivation therapy (ADT) at any time were excluded. Trifecta criteria at baseline were met in 72 patients (42% of all ADT-free patients with completed questionnaires). Both at 12 and 24 months after hypo-IGRT, 57% of the Trifecta patients at baseline were still meeting the Trifecta criteria (both oncological and functional success according to the SCP model). The main reason for failing the Trifecta criteria during follow-up was erectile dysfunction: in 18 patients after 6 months follow-up, in 12 patients after 12 months follow-up, and in eight patients after 24 months. Actuarial 2-year Trifecta failure-free survival rate was 44% (95% confidence interval 27-60%). In multivariate analysis no predictors of Trifecta failure were identified. Missing questionnaires was the main limitation of the study. The Trifecta and SCP

  6. Phase 2 Study of Accelerated Hypofractionated Thoracic Radiation Therapy and Concurrent Chemotherapy in Patients With Limited-Stage Small-Cell Lung Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xia, Bing; Department of Radiation Oncology, Hangzhou Cancer Hospital, Hangzhou; Hong, Ling-Zhi

    Purpose: To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting. Methods and Materials: Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 tomore » 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate. Results: Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation. Conclusion: Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC.« less

  7. Randomized phase III trial of concurrent chemoradiotherapy vs accelerated hyperfractionation radiotherapy in locally advanced head and neck cancer

    PubMed Central

    Chitapanarux, Imjai; Tharavichitkul, Ekkasit; Kamnerdsupaphon, Pimkhuan; Pukanhapan, Nantaka; Vongtama, Roy

    2013-01-01

    The aim of this study was to compare the efficacy and safety of concurrent chemoradiotherapy (CCRT) vs accelerated hyperfractionation with concomitant boost (CCB) as a primary treatment for patients with Stage III–IV squamous cell carcinoma of head and neck (SCCHN). A total of 85 non-metastatic advanced SCCHN patients were accrued from January 2003 to December 2007. Of these, 48 and 37 patients received CCRT and CCB, respectively. The patients were randomized to receive either three cycles of carboplatin and 5-fluorouracil plus conventional radiotherapy (CCRT, 66 Gy in 6.5 weeks) or hybrid accelerated radiotherapy (CCB, 70 Gy in 6 weeks). The primary endpoint was determined by locoregional control rate. The secondary endpoints were overall survival and toxicity. With a median follow-up of 43 months (range, 3–102), the 5-year locoregional control rate was 69.6% in the CCRT arm vs 55.0% in the CCB arm (P = 0.184). The 5-year overall survival rate was marginally significantly different (P = 0.05): 76.1% in the CCRT arm vs 63.5% in the CCB arm. Radiotherapy treatment interruptions of more than three days were 60.4% and 40.5% in the CCRT arm and CCB arm, respectively. The median total treatment time was 55.5 days in the CCRT arm and 49 days in the CCB arm. The rate of Grade 3–4 acute mucositis was significantly higher in the CCB arm (67.6% vs 41.7%, P = 0.01), but no high grade hematologic toxicities were found in the CCB arm (27.2% vs 0%). CCRT has shown a trend of improving outcome over CCB irradiation in locoregionally advanced head and neck cancer. PMID:23740894

  8. SU-C-17A-07: The Development of An MR Accelerator-Enabled Planning-To-Delivery Technique for Stereotactic Palliative Radiotherapy Treatment of Spinal Metastases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoogcarspel, S J; Kontaxis, C; Velden, J M van der

    2014-06-01

    Purpose: To develop an MR accelerator-enabled online planning-todelivery technique for stereotactic palliative radiotherapy treatment of spinal metastases. The technical challenges include; automated stereotactic treatment planning, online MR-based dose calculation and MR guidance during treatment. Methods: Using the CT data of 20 patients previously treated at our institution, a class solution for automated treatment planning for spinal bone metastases was created. For accurate dose simulation right before treatment, we fused geometrically correct online MR data with pretreatment CT data of the target volume (TV). For target tracking during treatment, a dynamic T2-weighted TSE MR sequence was developed. An in house developedmore » GPU based IMRT optimization and dose calculation algorithm was used for fast treatment planning and simulation. An automatically generated treatment plan developed with this treatment planning system was irradiated on a clinical 6 MV linear accelerator and evaluated using a Delta4 dosimeter. Results: The automated treatment planning method yielded clinically viable plans for all patients. The MR-CT fusion based dose calculation accuracy was within 2% as compared to calculations performed with original CT data. The dynamic T2-weighted TSE MR Sequence was able to provide an update of the anatomical location of the TV every 10 seconds. Dose calculation and optimization of the automatically generated treatment plans using only one GPU took on average 8 minutes. The Delta4 measurement of the irradiated plan agreed with the dose calculation with a 3%/3mm gamma pass rate of 86.4%. Conclusions: The development of an MR accelerator-enabled planning-todelivery technique for stereotactic palliative radiotherapy treatment of spinal metastases was presented. Future work will involve developing an intrafraction motion adaptation strategy, MR-only dose calculation, radiotherapy quality-assurance in a magnetic field, and streamlining the entire

  9. Hypofractionation Results in Reduced Tumor Cell Kill Compared to Conventional Fractionation for Tumors With Regions of Hypoxia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carlson, David J., E-mail: david.j.carlson@yale.ed; Yale University School of Medicine, Department of Therapeutic Radiology, New Haven, CT; Keall, Paul J.

    2011-03-15

    Purpose: Tumor hypoxia has been observed in many human cancers and is associated with treatment failure in radiation therapy. The purpose of this study is to quantify the effect of different radiation fractionation schemes on tumor cell killing, assuming a realistic distribution of tumor oxygenation. Methods and Materials: A probability density function for the partial pressure of oxygen in a tumor cell population is quantified as a function of radial distance from the capillary wall. Corresponding hypoxia reduction factors for cell killing are determined. The surviving fraction of a tumor consisting of maximally resistant cells, cells at intermediate levels ofmore » hypoxia, and normoxic cells is calculated as a function of dose per fraction for an equivalent tumor biological effective dose under normoxic conditions. Results: Increasing hypoxia as a function of distance from blood vessels results in a decrease in tumor cell killing for a typical radiotherapy fractionation scheme by a factor of 10{sup 5} over a distance of 130 {mu}m. For head-and-neck cancer and prostate cancer, the fraction of tumor clonogens killed over a full treatment course decreases by up to a factor of {approx}10{sup 3} as the dose per fraction is increased from 2 to 24 Gy and from 2 to 18 Gy, respectively. Conclusions: Hypofractionation of a radiotherapy regimen can result in a significant decrease in tumor cell killing compared to standard fractionation as a result of tumor hypoxia. There is a potential for large errors when calculating alternate fractionations using formalisms that do not account for tumor hypoxia.« less

  10. Accelerated Radiotherapy, Carbogen, and Nicotinamide (ARCON) in the Treatment of Advanced Bladder Cancer: Mature Results of a Phase II Nonrandomized Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoskin, Peter; Marie Curie Research Wing, Mount Vernon Hospital, Northwood, Middx; Rojas, Ana Ph.D.

    2009-04-01

    Purpose: We previously showed that accelerated radiotherapy combined with carbogen and nicotinamide (ARCON) was an effective approach to use in the radical treatment of patients with advanced bladder carcinoma. Interim analysis from this Phase II study showed that it achieved a high level of locoregional control and overall survival (OS) and an acceptable level of adverse events. Methods and Materials: From 1994 to 2000, a total of 105 consecutive patients with high-grade superficial or muscle-invasive bladder carcinoma were given accelerated radiotherapy (50-55 Gy in 4 weeks) with carbogen alone or ARCON. End points of the study were OS, disease-specific, andmore » local regional relapse-free survival, and for late adverse events, urinary (altered urination frequency, incontinence, hematuria, and urgency) and bowel dysfunction (stool frequency and blood loss). Results: At 5 and 10 years, local regional relapse-free survival rates were 44% after ARCON excluding the effect of salvage treatment and 62% after ARCON including the effect of salvage treatment (p = 0.04). Five- and 10-year rates were 35% and 27% for OS and 47% and 46% for disease-specific survival. The highest actuarial rate for Grade 3 or worse late urinary or bowel dysfunction was observed for altered urinary frequency (44% of patients had urinary events every 1 hour or less) and stool frequency of four or more events (26% at 5 years). Conclusions: Historic comparisons with other studies indicate no evidence of an increase in severe or worse adverse events and good permanent control of bladder disease after ARCON radiotherapy.« less

  11. [Current status and potential perspectives in classical radiotherapy technology].

    PubMed

    Dabić-Stanković, Kata M; Stanković, Jovan B; Radosević-Jelić, Ljiljana M

    2004-01-01

    After purchase of radiotherapy equipment in 2003, classic radiation therapy in Serbia will reach the highest world level. In order to define the highest standards in radiation technology, we analyzed the current status and potential perspectives of radiation therapy. An analysis of present situation in the USA, assumed as the most developed in the world, was done. Available data, collected in the last 3 years (equipment assortment, therapy modalities, workload and manpower) for 284 radiotherapy centers, out of potential 2050, were analyzed. Results were presented as crude percentage and matched to point current status. The analysis showed that CLINAC accelerators are the most popular (82.7%), as well as, ADAC (43.7%) and Focus (CMS) (27.4%) systems for therapy planning. Movement towards virtual simulation is evident (59.3%), although classic "simulation" is not fully eliminated from the radiotherapy chain. The most popular brachytherapy afterloader is Microselectron HDR (71%). About 64.4% centers use IMPAC communication/verification/record system that seems more open than Varis. All centers practice modern radiotherapy modalities and techniques (CPRT, IMRT, SRS/SRT, TBI, IORT, IVBHRT, HDR BHRT, etc.). CT and MRI availability is out of question, but PET is available in 3% of centers, however this percentage is rapidly growing. Up to 350 new patients per year are treated by one accelerator (about 35 pts. a day). Centers are relatively small and utilize 2-3 accelerators on average. Average FTE staffing norm is 4 radiation oncologists, 2-3 medical radiotherapy physicists, about 3 certified medical dosimetrists and about 6 radiotherapy technologists. In the past 5 years relative stagnation in classic radiotherapy has been observed. In spite of substantial investments in technology and consequent improvements, as well as wide introduction of computers in radiotherapy, radiotherapy results have not changed significantly. Vendor developement strategies do not point that

  12. Effect of external shielding for neutrons during radiotherapy for prostate cancer, considering the 2300 CD linear accelerator and voxel phantom

    NASA Astrophysics Data System (ADS)

    Thalhofer, J. L.; Roque, H. S.; Rebello, W. F.; Correa, S. A.; Silva, A. X.; Souza, E. M.; Batita, D. V. S.; Sandrini, E. S.

    2014-02-01

    Photoneutron production occurs when high energy photons, greater than 6.7 MeV, interact with linear accelerator head structures. In Brazil, the National Cancer Institute, one of the centers of reference in cancer treatment, uses radiation at 4 angles (0°, 90°, 180° and 270°) as treatment protocol for prostate cancer. With the objective of minimizing the dose deposited in the patient due to photoneutrons, this study simulated radiotherapy treatment using MCNPX, considering the most realistic environment; simulating the radiotherapy room, the Linac 2300 head, the MAX phantom and the treatment protocol with the accelerator operating at 18 MV. In an attempt to reduce the dose deposited by photoneutrons, an external shielding was added to the Linac 2300. Results show that the equivalent dose due to photoneutrons deposited in the patient diminished. The biggest reduction was seen in bone structures, such as the tibia and fibula, and mandible, at approximately 75%. Besides that, organs such as the brain, pancreas, small intestine, lungs and thyroid revealed a reduction of approximately 60%. It can be concluded that the shielding developed by our research group is efficient in neutron shielding, reducing the dose for the patient, and thus, the risk of secondary cancer, and increasing patient survival rates.

  13. Long-term Cardiac Mortality After Hypofractionated Radiation Therapy in Breast Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tjessem, Kristin Holm, E-mail: krtjes@ous-hf.no; Johansen, Safora; Malinen, Eirik

    Purpose: To explore very-long-term mortality from ischemic heart disease (IHD) after locoregional radiation therapy of breast cancer (BC) in relation to degree of hypofractionation and other treatment variables. Methods and Materials: Two hypofractionated regimens used for locoregional radiation therapy for BC from 1975 to 1991 were considered. Patients received 4.3 Gy × 2/week (10 fractions; target dose 43 Gy; n=1107) or 2.5 Gy × 5/week (20 fractions; target dose 50 Gy; n=459). To estimate cardiac doses, radiation fields were reconstructed in a planning system. Time to death from IHD was the endpoint, comparing the groups with each other and withmore » age-matched, cancer-free control individuals, modeled with the Cox proportional hazards model. Results: Patients given 4.3 Gy × 10 had an increased risk of dying of IHD compared with both the 2.5 Gy group (hazard ratio [HR] = 2.37; 95% confidence interval [CI]: 1.06-5.32; P=.036) and the control group (HR = 1.59; 95% CI: 1.13-2.23; P=.008). Photon beams for parasternal fields gave an increased risk of dying of IHD compared with electron beams (HR = 2.56; 95% CI: 1.12-5.84; P=.025). Multivariate analysis gave an increased risk for the 4.3-Gy versus 2.5-Gy regimen with borderline significance (HR = 2.90; 95% CI: 0.97-8.79; P=.057) but not for parasternal irradiation. Conclusions: The degree of hypofractionation and parasternal photon beams contributed to increased cardiac mortality in this patient cohort. Differences emerged after 12 to 15 years, indicating the need of more studies with observation time of 2 decades.« less

  14. On the importance of prompt oxygen changes for hypofractionated radiation treatments.

    PubMed

    Kissick, Michael; Campos, David; van der Kogel, Albert; Kimple, Randall

    2013-10-21

    This discussion is motivated by observations of prompt oxygen changes occurring prior to a significant number of cancer cells dying (permanently stopping their metabolic activity) from therapeutic agents like large doses of ionizing radiation. Such changes must be from changes in the vasculature that supplies the tissue or from the metabolic changes in the tissue itself. An adapted linear-quadratic treatment is used to estimate the cell survival variation magnitudes from repair and reoxygenation from a two-fraction treatment in which the second fraction would happen prior to significant cell death from the first fraction, in the large fraction limit. It is clear the effects of oxygen changes are likely to be the most significant factor for hypofractionation because of large radiation doses. It is a larger effect than repair. Optimal dose timing should be determined by the peak oxygen timing. A call is made to prioritize near real time measurements of oxygen dynamics in tumors undergoing hypofractionated treatments in order to make these treatments adaptable and patient-specific.

  15. Critical dose and toxicity index of organs at risk in radiotherapy: Analyzing the calculated effects of modified dose fractionation in non–small cell lung cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pedicini, Piernicola, E-mail: ppiern@libero.it; Strigari, Lidia; Benassi, Marcello

    2014-04-01

    To increase the efficacy of radiotherapy for non–small cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new “toxicity index” (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volumemore » histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V{sub 20} in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC.« less

  16. Synchrotron radiation external beam rotational radiotherapy of breast cancer: proof of principle.

    PubMed

    Di Lillo, Francesca; Mettivier, Giovanni; Castriconi, Roberta; Sarno, Antonio; Stevenson, Andrew W; Hall, Chris J; Häusermann, Daniel; Russo, Paolo

    2018-05-01

    The principle of rotational summation of the absorbed dose for breast cancer treatment with orthovoltage X-ray beams was proposed by J. Boone in 2012. Here, use of X-ray synchrotron radiation for image guided external beam rotational radiotherapy treatment of breast cancer is proposed. Tumor irradiation occurs with the patient in the prone position hosted on a rotating bed, with her breast hanging from a hole in the bed, which rotates around a vertical axis passing through the tumor site. Horizontal collimation of the X-ray beam provides for whole breast or partial breast irradiation, while vertical translation of the bed and successive rotations allow for irradiation of the full tumor volume, with dose rates which permit also hypofractionated treatments. In this work, which follows a previous preliminary report, results are shown of a full series of measurements on polyethylene and acrylic cylindrical phantoms carried out at the Australian Synchrotron, confirmed by Geant4 Monte Carlo simulations, intended to demonstrate the proof of principle of the technique. Dose measurements were carried out with calibrated ion chambers, radiochromic films and thermoluminescence dosimeters. The photon energy investigated was 60 keV. Image guidance may occur with the transmitted beam for contrast-enhanced breast computed tomography. For a horizontal beam collimation of 1.5 cm and rotation around the central axis of a 14 cm-diameter polyethylene phantom, a periphery-to-center dose ratio of 14% was measured. The simulations showed that under the same conditions the dose ratio decreases with increasing photon energy down to 10% at 175 keV. These values are comparable with those achievable with conventional megavoltage radiotherapy of breast cancer with a medical linear accelerator. Dose painting was demonstrated with two off-center `cancer foci' with 1.3 Gy and 0.6 Gy target doses. The use of a radiosensitizing agent for dose enhancement is foreseen.

  17. Differences in health related quality of life in the randomised ARTSCAN study; accelerated vs. conventional radiotherapy for head and neck cancer. A five year follow up.

    PubMed

    Nyqvist, Johanna; Fransson, Per; Laurell, Göran; Hammerlid, Eva; Kjellén, Elisabeth; Franzén, Lars; Söderström, Karin; Wickart-Johansson, Gun; Friesland, Signe; Sjödin, Helena; Brun, Eva; Ask, Anders; Nilsson, Per; Ekberg, Lars; Björk-Eriksson, Thomas; Nyman, Jan; Lödén, Britta; Lewin, Freddi; Reizenstein, Johan; Lundin, Erik; Zackrisson, Björn

    2016-02-01

    Health related quality of life (HRQoL) was assessed in the randomised, prospective ARTSCAN study comparing conventional radiotherapy (CF) with accelerated radiotherapy (AF) for head and neck cancer. 750 patients with squamous cell carcinoma (of any grade and stage) in the oral cavity, oro-, or hypopharynx or larynx (except T1-2, N0 glottic carcinoma) without distant metastases were randomised to either conventional fractionation (2 Gy/day, 5 days/week in 49 days, total dose 68 Gy) or accelerated fractionation (1.1+2.0 Gy/day, 5 days/week in 35 days, total dose 68 Gy). HRQoL was assessed with EORTC QLQ-C30, QLQ-H&N35 and HADS at baseline, at end of radiotherapy (eRT) and at 3 and 6 months and 1, 2 and 5 years after start of treatment. The AF group reported HRQoL was significantly lower at eRT and at 3 months for most symptoms, scales and functions. Few significant differences were noted between the groups at 6 months and 5 years. Scores related to functional oral intake never reached baseline. In comparison to CF, AF has a stronger adverse effect on HRQoL in the acute phase. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. A randomized controlled trial of conventional fraction and late course accelerated hyperfraction three-dimensional conformal radiotherapy for esophageal cancer.

    PubMed

    Wang, Jian-Hua; Lu, Xu-Jing; Zhou, Jian; Wang, Feng

    2012-01-01

    We compared the curative and side-effects in esophageal carcinoma treated by conventional fraction (CF) and late course accelerated hyperfraction (LCAF) three-dimensional conformal radiotherapy. Ninety-eight patients were randomly assigned to two different radiotherapy model groups. Fifty patients were treated using CF three-dimensional conformal radiotherapy at a total dose of 60-68 Gy; 2 Gy/F; 5 fractions/week (median 64 Gy), 48 patients were treated with LCAF (First CF-treated at the dose 40 Gy. Later, LCAF-treated 1.5 Gy/F; 2 fractions/day; 21-27 Gy; a total dose of 61-67 Gy; median 64 Gy). The data showed that the 1-, 2- and 3-year-survival rates in LCAF group were 79.2, 56.3, and 43.8%, compared to 74, 54, and 36% in CF group (P = 0.476). The 1-, 2- and 3-year-local control rates in LCAF group were 81.3, 62.5, and 50%, compared to 78, 58, and 42% in CF group (P = 0.454). In CF group, the incidence of radiation-induced esophagitis was lower than that in LCAF group (72 vs. 93.8%; P = 0.008) and there was no significant difference between rates of radiation-induced pneumonitis in CF and LCAF groups (10 vs. 6.25%; P = 0.498). It was concluded that the 1-, 2- and 3-year-local control and survival rates of esophageal carcinoma patients treated with LCAF were slightly better than CF radiotherapy; however, the radiation side-effects in LCAF group were greater than those in CF group.

  19. Prostate-specific antigen bounce after high-dose-rate prostate brachytherapy and hypofractionated external beam radiotherapy.

    PubMed

    Patel, Nita; Souhami, Luis; Mansure, Jose João; Duclos, Marie; Aprikian, Armen; Faria, Sergio; David, Marc; Cury, Fabio L

    2014-01-01

    To report the frequency, timing, and magnitude of prostate-specific antigen (PSA) bounce (PB) in patients who received high-dose-rate (HDR) brachytherapy (HDRB) plus hypofractionated external beam radiation therapy (HypoRT) and to assess a possible correlation between PB and biochemical failure (BF). Patients with intermediate-risk prostate cancer received 10Gy single-fraction (192)Ir HDRB followed by 50Gy in 20 daily fractions of HypoRT without androgen deprivation therapy. All patients had a minimum 2-year followup. The PB was defined as PSA elevation higher than 0.2ng/mL from previous measurement with subsequent drop to pre-bounce level. The BF was defined as PSA nadir+2ng/mL. A total of 114 patients treated between 2001 and 2009 were eligible for analysis. At a median followup of 66 months, the PB was found in 45 (39%) patients with a median time to bounce of 16 months (range, 3-76 months). The median time to PSA normalization after a PB was 9 months (range, 2-40 months). The median magnitude of PB was 0.45ng/mL (range, 0.2-6.62). The BF occurred in 12 (10.5%) patients of whom three had a PB. Median time to BF was 52.5 months. Four patients (3.5%) in the PB group fit the criteria for BF. The PB is common after HDRB and HypoRT and can occur up to 76 months after treatment. It can rarely fit the criteria for BF. The time to PB is shorter than the time to BF. There is a lower incidence of BF in patients with a PB. An acknowledgment of this phenomenon should be made when interpreting PSA results during followup to prevent unnecessary interventions. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  20. Hypofractionated intensity modulated irradiation for localized prostate cancer, results from a phase I/II feasibility study

    PubMed Central

    Junius, Sara; Haustermans, Karin; Bussels, Barbara; Oyen, Raymond; Vanstraelen, Bianca; Depuydt, Tom; Verstraete, Jan; Joniau, Steven; Van Poppel, Hendrik

    2007-01-01

    Background To assess acute (primary endpoint) and late toxicity, quality of life (QOL), biochemical or clinical failure (secondary endpoints) of a hypofractionated IMRT schedule for prostate cancer (PC). Methods 38 men with localized PC received 66 Gy (2.64 Gy) to prostate,2 Gy to seminal vesicles (50 Gy total) using IMRT. Acute toxicity was evaluated weekly during radiotherapy (RT), at 1–3 months afterwards using RTOG acute scoring system. Late side effects were scored at 6, 9, 12, 16, 20, 24 and 36 months after RT using RTOG/EORTC criteria. Quality of life was assessed by EORTC-C30 questionnaire and PR25 prostate module. Biochemical failure was defined using ASTRO consensus and nadir+2 definition, clinical failure as local, regional or distant relapse. Results None experienced grade III-IV toxicity. 10% had no acute genito-urinary (GU) toxicity, 63% grade I; 26% grade II. Maximum acute gastrointestinal (GI) scores 0, I, II were 37%, 47% and 16%. Maximal acute toxicity was reached weeks 4–5 and resolved within 4 weeks after RT in 82%. Grade II rectal bleeding needing coagulation had a peak incidence of 18% at 16 months after RT but is 0% at 24–36 months. One developed a urethral stricture at 2 years (grade II late GU toxicity) successfully dilated until now. QOL urinary symptom scores reached a peak incidence 1 month after RT but normalized 6 months later. Bowel symptom scores before, at 1–6 months showed similar values but rose slowly 2–3 years after RT. Nadir of sexual symptom scores was reached 1–6 months after RT but improved 2–3 years later as well as physical, cognitive and role functional scales. Emotional, social functional scales were lowest before RT when diagnosis was given but improved later. Two years after RT global health status normalized. Conclusion This hypofractionated IMRT schedule for PC using 25 fractions of 2.64 Gy did not result in severe acute side effects. Until now late urethral, rectal toxicities seemed acceptable as well

  1. [Hippocampus, brainstem and brain dose-volume constraints for fractionated 3-D radiotherapy and for stereotactic radiation therapy: Limits and perspectives].

    PubMed

    Gérard, M; Jumeau, R; Pichon, B; Biau, J; Blais, E; Horion, J; Noël, G

    2017-10-01

    Cerebral radiation-induced toxicities after radiotherapy (RT) of brain tumors are frequent. The protection of organs at risk (OAR) is crucial, especially for brain tumors, to preserve cognition in cancer survivors. Dose constraints of cerebral OAR used in conventional RT, radiosurgery (SRS) and stereotactic radiotherapy (SRT) are debated. In fact, they are based on historical cohorts or calculated with old mathematical models. Values of α/β ratio of cerebral OAR are also controversial leading to misestimate the equivalent dose in 2Gy fractions or the biological equivalent dose, especially during hypofractionated RT. Although recent progresses in medical imaging, the diagnosis of radionecrosis remains difficult. In this article, we propose a large review of dose constraints used for three major cerebral OAR: the brain stem, the hippocampus and the brain. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  2. Overview summary of clinical heavier-ion progress in Japan

    NASA Astrophysics Data System (ADS)

    Matsufuji, N.

    2017-06-01

    Swift ion beams such as carbon has unique characteristics suitable for treating deep-seated tumours. In Japan, carbon-ion radiotherapy was started in 1994 at Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences and more than 10,000 patients have been treated by Aug. 2016. Clinical outcomes show superior efficacy of carbon ions even against radioresistant tumour while keeping the quality of life at high level, and also the usefulness of hypofractionated irradiation down to the completion of the course of lung-cancer treatment in 1 day. During the decades, the improvement of hardware and software technology such as 3D scanning technique, superconducting rotating gantry or biology model have been carried out aiming at further optimized ion-beam radiotherapy as well as reducing the cost of the facility. The developed technology has been transferred to the following facilities. As of 2016, 5 carbon ion radiotherapy facilities are in operation in Japan.

  3. Theory, simulation and experiments for precise deflection control of radiotherapy electron beams.

    PubMed

    Figueroa, R; Leiva, J; Moncada, R; Rojas, L; Santibáñez, M; Valente, M; Velásquez, J; Young, H; Zelada, G; Yáñez, R; Guillen, Y

    2018-03-08

    Conventional radiotherapy is mainly applied by linear accelerators. Although linear accelerators provide dual (electron/photon) radiation beam modalities, both of them are intrinsically produced by a megavoltage electron current. Modern radiotherapy treatment techniques are based on suitable devices inserted or attached to conventional linear accelerators. Thus, precise control of delivered beam becomes a main key issue. This work presents an integral description of electron beam deflection control as required for novel radiotherapy technique based on convergent photon beam production. Theoretical and Monte Carlo approaches were initially used for designing and optimizing device´s components. Then, dedicated instrumentation was developed for experimental verification of electron beam deflection due to the designed magnets. Both Monte Carlo simulations and experimental results support the reliability of electrodynamics models used to predict megavoltage electron beam control. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. [Linear accelerator-based stereotactic radiation treatment of patients with medial middle fossa meningiomas].

    PubMed

    Golanov, A V; Cherekaev, V A; Serova, N K; Pronin, I N; Gorlachev, G E; Kotel'nikova, T M; Podoprigora, A E; Kudriavtseva, P A; Galkin, M V

    2010-01-01

    Medial middle fossa meningiomas are challenging for neurosurgical treatment. Invasion of cranial nerves and vessels leads to high risk of complications after removal of such meningiomas. Currently methods of conformal stereotactic radiation treatment are applied wider and wider for the discussed lesions. During a 3.5-year period 80 patients with medial middle fossa meningiomas were treated in Burdenko Moscow Neurosurgical Institute using linear accelerator "Novalis". In 31 case radiation treatment was preceded by surgical resection. In majority of patients symptoms included cranial nerve dysfunction: oculomotor disturbances in 62.5%, trigeminal impairment--in 37.5%, visual deficit--in 43.8%, facial nerve palsy--in 1.25%. 74 patients underwent radiotherapy with classical fractioning, 2--in hypofractionated mode and 4 received radiosurgery. In cases of classical fractioning mean marginal dose reached 46.3 Gy during 28-33 fractions, in hypofractioning (7 fractions)--31.5 Gy, in radiosurgery--16.25 Gy. Mean follow-up period was 18.4 months (6-42 months). Control of tumor growth was achieved in 97.5% of cases (78 patients): in 42 (52.5%) lesion shrinked, in 36 (45%) stabilization was observed. Clinical examination revealed improvement of visual function in 15 patients (18%) and deterioration in 2 (2.5%). No new neuropathies were found. Stereotactic radiation treatment is the method of choice for medial anterior and middle fossa meningiomas due to effective control of tumor progression and minimal rate of complications.

  5. Combination of longitudinal and circumferential three-dimensional esophageal dose distribution predicts acute esophagitis in hypofractionated reirradiation of patients with non-small-cell lung cancer treated in stereotactic body frame.

    PubMed

    Poltinnikov, Igor M; Fallon, Kevin; Xiao, Yian; Reiff, Jay E; Curran, Walter J; Werner-Wasik, Maria

    2005-07-01

    To evaluate dosimetric predictors of acute esophagitis (AE) and clinical outcome of patients with non-small-cell lung cancer (NSCLC) receiving reirradiation. Seventeen patients with NSCLC received reirradiation to the lung tumors/mediastinum, while immobilized in stereotactic body frame (SBF). CT simulation and hypofractionated three-dimensional radiotherapy were used. Two axial segments of esophagus contours merged together were defined as esophagus disc (ED). For each ED, the percentage (%) of the volume of esophageal circumference treated to % of prescribed dose (PD) was assessed. Number of EDs with 50% or any % of volume (V) of esophageal circumference receiving more than or equal to (>/=) 50%, 80%, and 100% of PD (50% V >/=50% PD; 50% V >/=80% PD; any % V >/=100% PD) were calculated. These dosimetric variables and the length of the esophagus within the radiation therapy (RT) port were correlated with AE using exact Wilcoxon test. A median RT dose was 32 Gy with a median fraction size of 4 Gy. Eleven of 13 patients presenting with pain and/or shortness of breath had complete or partial resolution of symptoms. Median survival time from the start of reirradiation in SBF until death was 5.5 months. AE was observed in 7 patients and resolved within 3 months of RT completion. No Grade 3 or higher events were noticed. The length of the esophagus within RT port did not predict for AE (p = 0.71). However, an increased number of EDs predicted for AE for the following dosimetric variables: 50% V >/=50% PD (p = 0.023), 50% V >/=80% PD (p = 0.047), and any % V >/=100% PD (p = 0.004). Patients with at least 2 EDs receiving >/=100% PD to any % V of circumference had AE compared to those with zero EDs. Reirradiation using hypofractionated three-dimensional radiotherapy and SBF immobilization is an effective strategy for palliation of symptoms in selected patients with recurrent NSCLC. The length of the esophagus in the RT field does not predict for AE. However, an increasing

  6. Challenges in Linear Accelerator Radiotherapy for Chordomas and Chondrosarcomas of the Skull Base: Focus on Complications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hauptman, Jason S., E-mail: jhauptman@mednet.ucla.edu; Barkhoudarian, Garni; Safaee, Michael

    2012-06-01

    Purpose: Intracranial chordomas and chondrosarcomas are histologically low-grade, locally invasive tumors that infiltrate the skull base. Currently, consensus therapy includes surgical resection and adjuvant radiotherapy. Radiation delivery is typically limited by the proximity of these tumors to critical skull base structures. Methods: This is a retrospective review of 13 cases of chordomas and 2 cases of chondroid chondrosarcomas of the skull based treated with linear accelerator stereotactic radiotherapy (SRT, n = 10) or stereotactic radiosurgery (SRS, n = 5). The average time to the most recent follow-up visit was 4.5 years. The tumor characteristics, treatment details, and outcomes were recorded.more » Each radiation plan was reviewed, and the dosage received by the brainstem, optic apparatus, and pituitary was calculated. Results: Of the 10 patients treated with SRT, 6 were found to have unchanged or decreased tumor size as determined from radiographic follow-up. Of the 5 patients treated with SRS, 3 were found to have stable or unchanged tumors at follow-up. The complications included 1 SRT patient who developed endocrinopathy, 2 patients (1 treated with SRS and the other with SRT), who developed cranial neuropathy, and 1 SRS patient who developed visual deficits. Additionally, 1 patient who received both SRS and SRT within 2 years for recurrence experienced transient medial temporal lobe radiation changes that resolved. Conclusions: Where proton beam therapy is unavailable, linear accelerator-based SRT or radiosurgery remains a safe option for adjuvant therapy of chordomas and chondrosarcomas of the skull base. The exposure of the optic apparatus, pituitary stalk, and brainstem must be considered during planning to minimize complications. If the optic apparatus is included in the 80% isodose line, it might be best to fractionate therapy. Exposure of the pituitary stalk should be kept to <30 Gy to minimize endocrine dysfunction. Brainstem exposure should

  7. Accelerated partial breast intensity-modulated radiotherapy in women who have prior breast augmentation.

    PubMed

    Leonard, Charles E; Johnson, Tim; Tallhamer, Michael; Howell, Kathryn; Kercher, Jane; Kaske, Terese; Barke, Lora; Sedlacek, Scot; Hobart, Tracy; Carter, Dennis L

    2011-06-01

    To examine the outcome of breast cancer patients who have prior breast augmentation treated with lumpectomy followed by accelerated partial breast external intensity-modulated radiotherapy (APBIMRT) with image-guided radiotherapy (IGRT). Four patients with previous elective subpectoral breast augmentation were enrolled on this APBIMRT trial. These four patients were treated with 10 equal twice daily 3.85 Gy fractions over 5 consecutive days (total dose of 38.5 Gy) using APBIMRT and IGRT. Patients were assessed for pain and cosmetic outcome (physician and a patient self-assessment). At last follow-up, two patients reported an excellent cosmetic results (at 2 years and at 8 months, respectively), one reported good cosmetic results (at 2 years), and one reported poor cosmetic results (at 20 months). Physicians rated the cosmetic outcomes as excellent in two (CEL; at 2 years and 8 months, respectively), good in one (CEL; at 20 months) and excellent in one (KTH; at 2 years). Three patients reported no breast/chest wall pain (two at 2 years and one at 1 year) and the fourth reported mild pain (at 20 months). The mean percent volume of ipsilateral breast receiving 100%, 75%, 50%, and 25% of the prescribed dose was 7.28%, 17.55%, 24.33%, and 33.1%, respectively. The mean breast, planning target volume (PTV), and implant volumes were 399.88 cc, 43.55 cc, and 313.36 cc, respectively. The mean breast prosthesis/total volume (breast tissue plus prosthesis) ratio was 44.55%. The mean PTV/ipsilateral breast and PTV/total volume ratios were 11.1% and 6.1%, respectively. The results show that a regimen of APBIMRT with IGRT is possible in patients who have prior breast augmentation. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Symptomatic Radiation Pneumonitis After Accelerated Partial Breast Irradiation Using Three-dimensional Conformal Radiotherapy.

    PubMed

    Shikama, Naoto; Kumazaki, Y U; Miyazawa, Kazunari; Miyaura, Kazunori; Kato, Shingo; Nakamura, Naoki; Kawamori, Jiro; Shimizuguchi, Takuya; Saito, Naoko; Saeki, Toshiaki

    2016-05-01

    To examine the relationship between symptomatic radiation pneumonitis and lung dose-volume parameters for patients receiving accelerated partial breast irradiation (APBI) using three dimensional-conformal radiotherapy (3D-CRT). The prescribed radiation dose was 30 Gy in 5 fractions over 10 days. Toxicity was graded according to the Common Terminology Criteria for Adverse Events (version 4.0). Fifty-five patients were enrolled from August 2010 to October 2013 and the median follow-up time was 30 months (range=18-46 months). Three patients (5%) developed grade 2 symptomatic radiation pneumonitis after 3D-CRT APBI. Among 16 patients with ILV10Gy (% ipsilateral lung receiving ≥10 Gy) of 10% or higher, three patients (19%) developed symptomatic radiation pneumonitis. This trend was not observed in any of the patients with ILV10Gy less than 10% (p=0.005). High ILV10Gy might be associated with symptomatic radiation pneumonitis after 3D-CRT APBI. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  9. Comparison of measured electron energy spectra for six matched, radiotherapy accelerators.

    PubMed

    McLaughlin, David J; Hogstrom, Kenneth R; Neck, Daniel W; Gibbons, John P

    2018-05-01

    This study compares energy spectra of the multiple electron beams of individual radiotherapy machines, as well as the sets of spectra across multiple matched machines. Also, energy spectrum metrics are compared with central-axis percent depth-dose (PDD) metrics. A lightweight, permanent magnet spectrometer was used to measure energy spectra for seven electron beams (7-20 MeV) on six matched Elekta Infinity accelerators with the MLCi2 treatment head. PDD measurements in the distal falloff region provided R 50 and R 80-20 metrics in Plastic Water ® , which correlated with energy spectrum metrics, peak mean energy (PME) and full-width at half maximum (FWHM). Visual inspection of energy spectra and their metrics showed whether beams on single machines were properly tuned, i.e., FWHM is expected to increase and peak height decrease monotonically with increased PME. Also, PME spacings are expected to be approximately equal for 7-13 MeV beams (0.5-cm R 90 spacing) and for 13-16 MeV beams (1.0-cm R 90 spacing). Most machines failed these expectations, presumably due to tolerances for initial beam matching (0.05 cm in R 90 ; 0.10 cm in R 80-20 ) and ongoing quality assurance (0.2 cm in R 50 ). Also, comparison of energy spectra or metrics for a single beam energy (six machines) showed outlying spectra. These variations in energy spectra provided ample data spread for correlating PME and FWHM with PDD metrics. Least-squares fits showed that R 50 and R 80-20 varied linearly and supralinearly with PME, respectively; however, both suggested a secondary dependence on FWHM. Hence, PME and FWHM could serve as surrogates for R 50 and R 80-20 for beam tuning by the accelerator engineer, possibly being more sensitive (e.g., 0.1 cm in R 80-20 corresponded to 2.0 MeV in FWHM). Results of this study suggest a lightweight, permanent magnet spectrometer could be a useful beam-tuning instrument for the accelerator engineer to (a) match electron beams prior to beam commissioning

  10. A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

    PubMed Central

    Budach, W; Hehr, T; Budach, V; Belka, C; Dietz, K

    2006-01-01

    Background Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX) to radiotherapy (RT) and to some extent also for the use of hyperfractionated radiation therapy (HFRT) and accelerated radiation therapy (AFRT) in locally advanced squamous cell carcinoma (SCC) of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. Methods Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in <4 weeks) on SCC of the oral cavity, oropharynx, hypopharynx, and larynx published as full paper or in abstract form between 1975 and 2003 were eligible. Trials comparing RT alone with concurrent or alternating chemoradiation (5-fluorouracil (5-FU), cisplatin, carboplatin, mitomycin C) were analyzed according to the employed radiation schedule and the used CHX regimen. Studies comparing conventionally fractionated radiotherapy (CFRT) with either HFRT or AFRT without CHX were separately examined. End point of the meta-analysis was overall survival. Results Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p < 0.001). Separate analyses by cytostatic drug indicate a prolongation of survival of 24.0 months, 16.8 months, 6.7 months, and 4.0 months, respectively, for the simultaneous administration of 5-FU, cisplatin-based, carboplatin-based, and mitomycin C-based CHX to RT (each p < 0.01). Whereas no significant gain in overall survival was observed for AFRT in comparison to CFRT, a substantial prolongation of median survival (14.2 months, p < 0.001) was seen for HFRT compared to CFRT (both without CHX). Conclusion RT combined with simultaneous 5-FU

  11. Application of biological effective dose (BED) to estimate the duration of symptomatic relief and repopulation dose equivalent in palliative radiotherapy and chemotherapy.

    PubMed

    Jones, Bleddyn; Cominos, Matilda; Dale, Roger G

    2003-03-01

    To investigate the potential for mathematic modeling in the assessment of symptom relief in palliative radiotherapy and cytotoxic chemotherapy. The linear quadratic model of radiation effect with the overall treatment time and the daily dose equivalent of repopulation is modified to include the regrowth time after completion of therapy. The predicted times to restore the original tumor volumes after treatment are dependent on the biological effective dose (BED) delivered and the repopulation parameter (K); it is also possible to estimate K values from analysis of palliative treatment response durations. Hypofractionated radiotherapy given at a low total dose may produce long symptom relief in slow-growing tumors because of their low alpha/beta ratios (which confer high fraction sensitivity) and their slow regrowth rates. Cancers that have high alpha/beta ratios (which confer low fraction sensitivity), and that are expected to repopulate rapidly during therapy, are predicted to have short durations of symptom control. The BED concept can be used to estimate the equivalent dose of radiotherapy that will achieve the same duration of symptom relief as palliative chemotherapy. Relatively simple radiobiologic modeling can be used to guide decision-making regarding the choice of the most appropriate palliative schedules and has important implications in the design of radiotherapy or chemotherapy clinical trials. The methods described provide a rationalization for treatment selection in a wide variety of tumors.

  12. Carbon-ion radiotherapy for marginal lymph node recurrences of cervical cancer after definitive radiotherapy: a case report.

    PubMed

    Tamaki, Tomoaki; Ohno, Tatsuya; Kiyohara, Hiroki; Noda, Shin-ei; Ohkubo, Yu; Ando, Ken; Wakatsuki, Masaru; Kato, Shingo; Kamada, Tadashi; Nakano, Takashi

    2013-04-05

    Recurrences of cervical cancer after definitive radiotherapy often occur at common iliac or para-aortic lymph nodes as marginal lymph node recurrences. Patients with these recurrences have a chance of long-term survival by optimal re-treatment with radiotherapy. However, the re-irradiation often overlaps the initial and the secondary radiotherapy fields and can result in increased normal tissue toxicities in the bowels or the stomach. Carbon-ion radiotherapy, a form of particle beam radiotherapy using accelerated carbon ions, offers more conformal and sharp dose distribution than X-ray radiotherapy. Therefore, this approach enables the delivery of high radiation doses to the target while sparing its surrounding normal tissues. Marginal lymph node recurrences in common iliac lymph nodes after radiotherapy were treated successfully by carbon-ion radiotherapy in two patients. These two patients were initially treated with a combination of external beam radiotherapy and intracavitary and interstitial brachytherapy. However, the diseases recurred in the lymph nodes near the border of the initial radiotherapy fields after 22 months and 23 months. Because re-irradiation with X-ray radiotherapy may deliver high doses to a section of the bowels, carbon-ion radiotherapy was selected to treat the lymph node recurrences. A total dose of 48 Gy (RBE) in 12 fractions over 3 weeks was given to the lymph node recurrences, and the tumors disappeared completely with no severe acute toxicities. The two patients showed no evidence of disease for 75 months and 63 months after the initial radiotherapy and for 50 months and 37 months after the carbon-ion radiotherapy, respectively. No severe late adverse effects are observed in these patients. The two presented cases suggest that the highly conformal dose distribution of carbon-ion radiotherapy may be beneficial in the treatment of marginal lymph node recurrences after radiotherapy. In addition, the higher biological effect of carbon

  13. Treatment of advanced canine anal sac adenocarcinoma with hypofractionated radiation therapy: 77 cases (1999-2013).

    PubMed

    McQuown, B; Keyerleber, M A; Rosen, K; McEntee, M C; Burgess, K E

    2017-09-01

    Currently no standard of care exists for advanced, inoperable or metastatic anal sac adenocarcinoma (ASAC). The objective of this retrospective study was to assess the role of hypofractionated radiation therapy (RT) in 77 dogs with measurable ASAC. A total of 38% of dogs experienced a partial response to RT. For dogs presenting with clinical signs related to the tumour, improvement or resolution of signs was noted in 63%. For dogs presenting with hypercalcemia of malignancy, resolution was noted in 31% with RT alone and an additional 46% with radiation, prednisone, and/or bisphosphonates. Median overall survival was 329 days (range: 252-448 days). Median progression free survival was 289 days (range: 224-469). There was no difference in survival based on radiation protocol, use of chemotherapy, previous surgery or advanced stage. Radiation toxicities were mild and infrequent. Hypofractionated RT is well tolerated and is applicable in the treatment of advanced primary, locoregional or metastatic ASAC. © 2016 John Wiley & Sons Ltd.

  14. Hypofractionated Intensity Modulated Radiation Therapy in Combined Modality Treatment for Bladder Preservation in Elderly Patients With Invasive Bladder Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turgeon, Guy-Anne; Souhami, Luis, E-mail: luis.souhami@muhc.mcgill.ca; Cury, Fabio L.

    2014-02-01

    Purpose/Objective(s): To review our experience with bladder-preserving trimodality treatment (TMT) using hypofractionated intensity modulated radiation therapy (IMRT) for the treatment of elderly patients with muscle-invasive bladder cancer. Methods and Materials: Retrospective study of elderly patients treated with TMT using hypofractionated IMRT (50 Gy in 20 fractions) with concomitant weekly radiosensitizing chemotherapy. Eligibility criteria were as follows: age ≥70 years, a proven diagnosis of muscle-invasive transitional cell bladder carcinoma, stage T2-T3N0M0 disease, and receipt of TMT with curative intent. Response rate was assessed by cystoscopic evaluation and bladder biopsy. Results: 24 patients with a median age of 79 years were eligible.more » A complete response was confirmed in 83% of the patients. Of the remaining patients, 1 of them underwent salvage cystectomy, and no disease was found in the bladder on histopathologic assessment. After a median follow-up time of 28 months, of the patients with a complete response, 2 patients had muscle-invasive recurrence, 1 experienced locoregional failure, and 3 experienced distant metastasis. The overall and cancer-specific survival rates at 3 years were 61% and 71%, respectively. Of the surviving patients, 75% have a disease-free and functioning bladder. All patients completed hypofractionated IMRT, and 19 patients tolerated all 4 cycles of chemotherapy. Acute grade 3 gastrointestinal or genitourinary toxicities occurred in only 4% of the patients, and acute grade 3 or 4 hematologic toxicities, liver toxicities, or both were experienced by 17% of the cohort. No patient experienced grade 4 gastrointestinal or genitourinary toxicity. Conclusions: Hypofractionated IMRT with concurrent radiosensitizing chemotherapy appears to be an effective and well-tolerated curative treatment strategy in the elderly population and should be considered for patients who are not candidates for cystectomy or who wish to avoid

  15. Risk of Late Toxicity in Men Receiving Dose-Escalated Hypofractionated Intensity Modulated Prostate Radiation Therapy: Results From a Randomized Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoffman, Karen E., E-mail: khoffman1@mdanderson.org; Voong, K. Ranh; Pugh, Thomas J.

    Objective: To report late toxicity outcomes from a randomized trial comparing conventional and hypofractionated prostate radiation therapy and to identify dosimetric and clinical parameters associated with late toxicity after hypofractionated treatment. Methods and Materials: Men with localized prostate cancer were enrolled in a trial that randomized men to either conventionally fractionated intensity modulated radiation therapy (CIMRT, 75.6 Gy in 1.8-Gy fractions) or to dose-escalated hypofractionated IMRT (HIMRT, 72 Gy in 2.4-Gy fractions). Late (≥90 days after completion of radiation therapy) genitourinary (GU) and gastrointestinal (GI) toxicity were prospectively evaluated and scored according to modified Radiation Therapy Oncology Group criteria. Results: 101 men receivedmore » CIMRT and 102 men received HIMRT. The median age was 68, and the median follow-up time was 6.0 years. Twenty-eight percent had low-risk, 71% had intermediate-risk, and 1% had high-risk disease. There was no difference in late GU toxicity in men treated with CIMRT and HIMRT. The actuarial 5-year grade ≥2 GU toxicity was 16.5% after CIMRT and 15.8% after HIMRT (P=.97). There was a nonsignificant numeric increase in late GI toxicity in men treated with HIMRT compared with men treated with CIMRT. The actuarial 5-year grade ≥2 GI toxicity was 5.1% after CIMRT and 10.0% after HIMRT (P=.11). In men receiving HIMRT, the proportion of rectum receiving 36.9 Gy, 46.2 Gy, 64.6 Gy, and 73.9 Gy was associated with the development of late GI toxicity (P<.05). The 5-year actuarial grade ≥2 GI toxicity was 27.3% in men with R64.6Gy ≥ 20% but only 6.0% in men with R64.6Gy < 20% (P=.016). Conclusions: Dose-escalated IMRT using a moderate hypofractionation regimen (72 Gy in 2.4-Gy fractions) can be delivered safely with limited grade 2 or 3 late toxicity. Minimizing the proportion of rectum that receives moderate and high dose decreases the risk of late rectal toxicity after this

  16. Laser-driven particle acceleration for radiobiology and radiotherapy: where we are and where we are going

    NASA Astrophysics Data System (ADS)

    Giulietti, Antonio

    2017-05-01

    Radiation therapy of tumors progresses continuously and so do devices, sharing a global market of about $ 4 billions, growing at an annual rate exceeding 5%. Most of the progress involves tumor targeting, multi-beam irradiation, reduction of damage on healthy tissues and critical organs, dose fractioning. This fast-evolving scenario is the moving benchmark for the progress of the laser-based accelerators towards clinical uses. As for electrons, both energy and dose requested by radiotherapy are available with plasma accelerators driven by lasers in the power range of tens of TW but several issues have still to be faced before getting a prototype device for clinical tests. They include capability of varying electron energy, stability of the process, reliability for medical users. On the other side hadron therapy, presently applied to a small fraction of cases but within an exponential growth, is a primary option for the future. With such a strong motivation, research on laser-based proton/ion acceleration has been supported in the last decade in order to get performances suitable to clinical standards. None of these performances has been achieved so far with laser techniques. In the meantime a rich crop of data have been obtained in radiobiological experiments performed with beams of particles produced with laser techniques. It is quite significant however that most of the experiments have been performed moving bio samples to laser labs, rather moving laser equipment to bio labs or clinical contexts. This give us the measure that laser community cannot so far provide practical devices usable by non-laser people.

  17. Stereotactic Body Radiotherapy in the Management of Oligometastatic Disease.

    PubMed

    Ahmed, Kamran A; Torres-Roca, Javier F

    2016-01-01

    The treatment of oligometastatic disease has become common as imaging techniques have advanced and the management of systemic disease has improved. Use of highly targeted, hypofractionated regimens of stereotactic body radiotherapy (SBRT) is now a primary management option for patients with oligometastatic disease. The properties of SBRT are summarized and the results of retrospective and prospective studies of SBRT use in the management of oligometastases are reviewed. Future directions of SBRT, including optimizing dose and fractionation schedules, are also discussed. SBRT can deliver highly conformal, dosed radiation treatments for ablative tumors in a few treatment sessions. Phase 1/2 trials and retrospective institutional results support use of SBRT as a treatment option for oligometastatic disease metastasized to the lung, liver, and spine, and SBRT offers adequate toxicity profiles with good rates of local control. Future directions will involve optimizing dose and fractionation schedules for select histologies to improve rates of local control while limiting toxicity to normal structures. SBRT offers an excellent management option for patients with oligometastases. However, additional research is still needed to optimize dose and fractionation schedules.

  18. Clinical outcomes of whole pelvis radiotherapy and stereotactic body radiotherapy boost for intermediate- and high-risk prostate cancer.

    PubMed

    Kim, Hun Jung; Phak, Jeong Hoon; Kim, Woo Chul

    2017-10-01

    We report our experience with Cyberknife to deliver hypofractionated stereotactic body radiotherapy (SBRT) boost combined with whole pelvis radiotherapy (WPRT) to patients with intermediate- to high-risk prostate cancer. From March 2008 to July 2014, 39 patients with newly diagnosed, intermediate- and high-risk (National Comprehensive Cancer Network definition) localized prostate cancer were treated with WPRT and SBRT boost. The whole pelvis dose was 45 Gy (25 fractions of 1.8 Gy) and the SBRT boost dose was 21 Gy (3 fractions of 7 Gy). No one received androgen deprivation therapy before biochemical relapse. The acute and late toxicities were recorded using the Radiation Therapy Oncology Group scale. Prostate-specific antigen (PSA) response was monitored. Thirty-nine patients with a median 53.6 months (range 14-74 months) follow-up were analyzed. The median pretreatment PSA was 15.97 ng/mL. The estimated 5-year biochemical failure (BCF)-free survival was 94.7%. Two BCFs were observed in only high-risk group. The median PSA nadir was 0.30 ng/mL at median 36 months and PSA bounce occurred in 15.4% (n = 6) of patients at median 12 months. No grade 3 acute toxicity was noted. A total of 23% of the patients had grade 2 acute genitourinary (GU) toxicities and 21% had grade 2 acute gastrointestinal (GI) toxicities. At 2 months, most complications had returned to baseline. GU and GI toxicities were observed. WPRT followed by SBRT boost using Cyberknife in intermediate- and high-risk prostate cancer is feasible with minimal toxicity and encouraging BCF-free survival. © 2016 John Wiley & Sons Australia, Ltd.

  19. A TCP model for external beam treatment of intermediate-risk prostate cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Walsh, Sean; Putten, Wil van der

    2013-03-15

    Purpose: Biological models offer the ability to predict clinical outcomes. The authors describe a model to predict the clinical response of intermediate-risk prostate cancer to external beam radiotherapy for a variety of fractionation regimes. Methods: A fully heterogeneous population averaged tumor control probability model was fit to clinical outcome data for hyper, standard, and hypofractionated treatments. The tumor control probability model was then employed to predict the clinical outcome of extreme hypofractionation regimes, as utilized in stereotactic body radiotherapy. Results: The tumor control probability model achieves an excellent level of fit, R{sup 2} value of 0.93 and a root meanmore » squared error of 1.31%, to the clinical outcome data for hyper, standard, and hypofractionated treatments using realistic values for biological input parameters. Residuals Less-Than-Or-Slanted-Equal-To 1.0% are produced by the tumor control probability model when compared to clinical outcome data for stereotactic body radiotherapy. Conclusions: The authors conclude that this tumor control probability model, used with the optimized radiosensitivity values obtained from the fit, is an appropriate mechanistic model for the analysis and evaluation of external beam RT plans with regard to tumor control for these clinical conditions.« less

  20. Supratentorial primitive neuroectodermal tumors (S-PNET) in children: A prospective experience with adjuvant intensive chemotherapy and hyperfractionated accelerated radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Massimino, Maura; Gandola, Lorenza; Spreafico, Filippo

    Purpose: Supratentorial primitive neuroectodermal tumors (S-PNET) are rare and have a grim prognosis, frequently taking an aggressive course with local relapse and metastatic spread. We report the results of a mono-institutional therapeutic trial. Methods and Materials: We enrolled 15 consecutive patients to preradiation chemotherapy (CT) consisting of high-dose methotrexate, high-dose etoposide, high-dose cyclophosphamide, and high-dose carboplatin, craniospinal irradiation (CSI) with hyperfractionated accelerated radiotherapy (HART) plus focal boost, maintenance with vincristine/lomustine or consolidation with high-dose thiotepa followed by autologous stem-cell rescue. Results: Median age was 9 years; 7 were male, 8 female. Site of disease was pineal in 3, elsewhere inmore » 12. Six patients were had no evidence of disease after surgery (NED). Of those with evidence of disease after surgery (ED), 2 had central nervous system spread. Of the 9 ED patients, 2 had complete response (CR) and 2 partial response (PR) after CT, 4 stable disease, and 1 progressive disease. Of the 7 ED patients before radiotherapy, 1 had CR, 4 PR, and 2 minor response, thus obtaining a 44% CR + PR after CT and 71% after HART. Because of rapid progression in 2 of the first 5 patients, high-dose thiotepa was systematically adopted after HART in the subsequent 10 patients. Six of 15 patients relapsed (4 locally, 1 locally with dissemination, 1 with dissemination) a mean of 6 months after starting CT, 2 developed second tumors; 5 of 6 relapsers died at a median of 13 months. Three-year progression-free survival, event-free survival, and overall survival were 54%, 34%, and 61%, respectively. Conclusion: Hyperfractionated accelerated RT was the main tool in obtaining responses in S-PNET; introducing the myeloablative phase improved the prognosis (3/10 vs. 3/5 relapses), though the outcome remained unsatisfactory despite the adoption of this intensive treatment.« less

  1. SU-F-J-124: Reduction in Dosimetric Impact of Motion Using VMAT Compared to IMRT in Hypofractionated Prostate Cancer Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ravindranath, B; Xiong, J; Happersett, L

    2016-06-15

    Purpose: To quantify and compare the dosimetric impact of motion management correction strategies during VMAT and IMRT for hypofractionated prostate treatment. Methods: Two arc VMAT and 9 field IMRT plans were generated for two prostate cancer patients undergoing hypofractionated radiotherapy (7.5Gy × 5 and 8Gy × 5). 212 motion traces were retrospectively extracted from treatment records of prostate cancer patients with implanted Calypso beacons. Dose to the CTV and normal tissues was reconstructed for each trace and plan taking into account the actual treatment delivery time. Following motion correction scenarios were simulated: (1) VMAT plan – (a) No correction, (b)more » correction between arcs, (c) correction every 20 degrees of gantry rotation and (2) IMRT plan - (a) No correction,(b) correction between fields. Two mm action threshold for position correction was assumed. The 5–95% confidence interval (CI) range was extracted from the family of DVHs for each correction scenario. Results: Treatment duration for 8Gy plan (VMAT vs IMRT) was 3 vs 12 mins and for 7.5Gy plan was 3 vs 9 mins. In the absence of correction, the VMAT 5–−95% CI dose spread was, on average, less than the IMRT dose spread by 2% for CTVD95, 9% for rectalwall (RW) D1cc and 9% for bladderwall (BW) D53. Further, VMAT b/w arcs correction strategy reduced the spread about the planned value compared to IMRT b/w fields correction by: 1% for CTVD95, 2.6% for RW1cc and 2% for BWD53. VMAT 20 degree strategy led to greater reduction in dose spread compared to IMRT by: 2% for CTVD95, 4.5% for RW1cc and 6.7% for BWD53. Conclusion: In the absence of a correction strategy, the limited motion during VMAT’s shorter delivery times translates into less motion-induced dosimetric degradation than IMRT. Performing limited periodic motion correction during VMAT can yield excellent conformity to planned values that is superior to IMRT. This work was partially supported by Varian Medical Systems.« less

  2. [Description of latest generation equipment in external radiotherapy].

    PubMed

    Pellejero, S; Lozares, S; Mañeru, F

    2009-01-01

    Both the planning systems and the form of administering radiotherapy have changed radically since the introduction of 3D planning. At present treatment planning based on computerised axial tomography (CAT) images is standard practice in radiotherapy services. In recent years lineal accelerators for medical use have incorporated technology capable of administering intensity modulated radiation beams (IMRT). With this mode distributions of conformed doses are generated that adjust to the three dimensional form of the white volume, providing appropriate coverage and a lower dose to nearby risk organs. The use of IMRT is rapidly spreading amongst radiotherapy centres throughout the world. This growing use of IMRT has focused attention on the need for greater control of the geometric uncertainties in positioning the patient and control of internal movements. To this end, both flat and volumetric image systems have been incorporated into the treatment equipment, making image-guided radiotherapy (IGRT) possible. This article offers a brief description of the latest advances included in the planning and administration of radiotherapy treatment.

  3. β1 integrin- and JNK-dependent tumor growth upon hypofractionated radiation.

    PubMed

    Sayeed, Aejaz; Lu, Huimin; Liu, Qin; Deming, David; Duffy, Alexander; McCue, Peter; Dicker, Adam P; Davis, Roger J; Gabrilovich, Dmitry; Rodeck, Ulrich; Altieri, Dario C; Languino, Lucia R

    2016-08-16

    Radiation therapy is an effective cancer treatment modality although tumors invariably become resistant. Using the transgenic adenocarcinoma of mouse prostate (TRAMP) model system, we report that a hypofractionated radiation schedule (10 Gy/day for 5 consecutive days) effectively blocks prostate tumor growth in wild type (β1wt /TRAMP) mice as well as in mice carrying a conditional ablation of β1 integrins in the prostatic epithelium (β1pc-/- /TRAMP). Since JNK is known to be suppressed by β1 integrins and mediates radiation-induced apoptosis, we tested the effect of SP600125, an inhibitor of c-Jun amino-terminal kinase (JNK) in the TRAMP model system. Our results show that SP600125 negates the effect of radiation on tumor growth in β1pc-/- /TRAMP mice and leads to invasive adenocarcinoma. These effects are associated with increased focal adhesion kinase (FAK) expression and phosphorylation in prostate tumors in β1pc-/- /TRAMP mice. In marked contrast, radiation-induced tumor growth suppression, FAK expression and phosphorylation are not altered by SP600125 treatment of β1wt /TRAMP mice. Furthermore, we have reported earlier that abrogation of insulin-like growth factor receptor (IGF-IR) in prostate cancer cells enhances the sensitivity to radiation. Here we further explore the β1/IGF-IR crosstalk and report that β1 integrins promote cell proliferation partly by enhancing the expression of IGF-IR. In conclusion, we demonstrate that β1 integrin-mediated inhibition of JNK signaling modulates tumor growth rate upon hypofractionated radiation.

  4. Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chapet, Olivier, E-mail: olivier.chapet@chu-lyon.fr; EMR3738, Université Lyon 1, Lyon; Decullier, Evelyne

    Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Eventsmore » version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity.« less

  5. Rectal bleeding after high-dose-rate brachytherapy combined with hypofractionated external-beam radiotherapy for localized prostate cancer: Impact of rectal dose in high-dose-rate brachytherapy on occurrence of grade 2 or worse rectal bleeding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akimoto, Tetsuo; Katoh, Hiroyuki; Kitamoto, Yoshizumi

    2006-06-01

    Purpose: To evaluate the incidence of Grade 2 or worse rectal bleeding after high-dose-rate (HDR) brachytherapy combined with hypofractionated external-beam radiotherapy (EBRT), with special emphasis on the relationship between the incidence of rectal bleeding and the rectal dose from HDR brachytherapy. Methods and Materials: The records of 100 patients who were treated by HDR brachytherapy combined with EBRT for {>=}12 months were analyzed. The fractionation schema for HDR brachytherapy was prospectively changed, and the total radiation dose for EBRT was fixed at 51 Gy. The distribution of the fractionation schema used in the patients was as follows: 5 Gy xmore » 5 in 13 patients; 7 Gy x 3 in 19 patients; and 9 Gy x 2 in 68 patients. Results: Ten patients (10%) developed Grade 2 or worse rectal bleeding. Regarding the correlation with dosimetric factors, no significant differences were found in the average percentage of the entire rectal volume receiving 30%, 50%, 80%, and 90% of the prescribed radiation dose from EBRT between those with bleeding and those without. The average percentage of the entire rectal volume receiving 10%, 30%, 50%, 80%, and 90% of the prescribed radiation dose from HDR brachytherapy in those who developed rectal bleeding was 77.9%, 28.6%, 9.0%, 1.5%, and 0.3%, respectively, and was 69.2%, 22.2%, 6.6%, 0.9%, and 0.4%, respectively, in those without bleeding. The differences in the percentages of the entire rectal volume receiving 10%, 30%, and 50% between those with and without bleeding were statistically significant. Conclusions: The rectal dose from HDR brachytherapy for patients with prostate cancer may have a significant impact on the incidence of Grade 2 or worse rectal bleeding.« less

  6. The influence of simultaneous integrated boost, hypofractionation and oncoplastic surgery on cosmetic outcome and PROMs after breast conserving therapy.

    PubMed

    Lansu, J T P; Essers, M; Voogd, A C; Luiten, E J T; Buijs, C; Groenendaal, N; Poortmans, P M H

    2015-10-01

    We retrospectively investigated the possible influence of a simultaneous integrated boost (SIB), hypofractionation and oncoplastic surgery on cosmetic outcome in 125 patients with stage I-II breast cancer treated with breast conserving therapy (BCT). The boost was given sequentially (55%) or by SIB (45%); fractionation was conventional (83%) or hypofractionated (17%); the surgical technique was a conventional lumpectomy (74%) or an oncoplastic technique (26%). We compared cosmetic results subjectively using a questionnaire independently completed by the patient and by the physician and objectively with the BCCT.core software. Independent-samples T-tests were used to compare outcome in different groups. Patients also completed the EORTC QLQ C30 and BR23. Univariate analyses indicated no significant differences of the cosmetic results (P ≤ 0.05) for the type of boost or fractionation. However, the conventional lumpectomy group scored significantly better than the oncoplastic group in the BCCT.core evaluation, without a significant difference in the subjective cosmetic evaluation. Quality of life outcome was in favour of SIB, hypofractionation and conventional surgery. Our study indicates that the current RT techniques seem to be safe for cosmetic outcome and quality of life. Further investigation is needed to verify the possible negative influence of oncoplastic surgery on the cosmetic outcome and the quality of life as this technique is especially indicated for patients with an unfavourable tumour/breast volume ratio. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Long-Term Outcome and Morbidity After Treatment With Accelerated Radiotherapy and Weekly Cisplatin for Locally Advanced Head-and-Neck Cancer: Results of a Multidisciplinary Late Morbidity Clinic

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ruetten, Heidi, E-mail: h.rutten@rther.umcn.nl; Pop, Lucas A.M.; Janssens, Geert O.R.J.

    2011-11-15

    Purpose: To evaluate the long-term outcome and morbidity after intensified treatment for locally advanced head-and-neck cancer. Methods and Materials: Between May 2003 and December 2007, 77 patients with Stage III to IV head-and-neck cancer were treated with curative intent. Treatment consisted of accelerated radiotherapy to a dose of 68 Gy and concurrent cisplatin. Long-term survivors were invited to a multidisciplinary outpatient clinic for a comprehensive assessment of late morbidity with special emphasis on dysphagia, including radiological evaluation of swallowing function in all patients. Results: Compliance with the treatment protocol was high, with 87% of the patients receiving at least fivemore » cycles of cisplatin and all but 1 patient completing the radiotherapy as planned. The 5-year actuarial disease-free survival and overall survival rates were 40% and 47%, respectively. Locoregional recurrence-free survival at 5 years was 61%. The 5-year actuarial rates of overall late Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) Grade 3 and Grade 4 toxicity were 52% and 25% respectively. Radiologic evaluation after a median follow-up of 44 months demonstrated impaired swallowing in 57% of the patients, including 23% with silent aspiration. Subjective assessment using a systematic scoring system indicated normalcy of diet in only 15.6% of the patients. Conclusion: This regimen of accelerated radiotherapy with weekly cisplatin produced favorable tumor control rates and survival rates while compliance was high. However, comprehensive assessment by a multidisciplinary team of medical and paramedical specialists revealed significant long-term morbidity in the majority of the patients, with dysphagia being a major concern.« less

  8. Radiotherapy in Italy after conservative treatment of early breast cancer. A survey by the Italian Society of Radiation Oncology (AIRO).

    PubMed

    Aristei, Cynthia; Amichetti, Maurizio; Ciocca, Mario; Nardone, Luigia; Bertoni, Filippo; Vidali, Cristiana

    2008-01-01

    The aim of surveys on clinical practice is to stimulate discussion and optimize practice. In this paper the current Italian radiotherapy practice after breast-conserving surgery for early breast cancer is described and adherence to national and international guidelines is assessed. Furthermore, results are compared with an earlier survey in northern Italy and international reports. A multiple-choice questionnaire sent to all 138 Italian radiation oncology centers. 48% of centers responded. Most performed breast-conserving surgery when tumor size was < or =3 cm. All centers routinely performed axillary dissection; 45 carried out sentinel node biopsy followed by axillary dissection when the sentinel node was positive. Most centers re-excised when resection margins were positive. The median interval between surgery and radiotherapy, when chemotherapy was not administered, was 60 days. Adjuvant chemotherapy was preferably administered before radiotherapy. Regional lymph nodes were never irradiated in 10 centers; in all others irradiation depended on the number of positive lymph nodes and/or involvement of axillary fat and/or tumor location in medial quadrants. All centers used standard fractionation; hypofractionated schemes were available in 6. Most centers used 4-6 MV photons. In 59 centers the boost dose of 10 Gy could be increased if margins were not negative. All centers ensured patient setup reproducibility. Treatment planning was computerized in 59 centers. The irradiation dose was prescribed at the ICRU point in 56 centers and portal films were made in 54 centers. Intraoperative radiotherapy was used in 4 centers: for partial breast irradiation in 1 and for boost administration in 3 centers. Although the quality of radiotherapy delivery has improved in Italy in recent years, approaches that do not conform to international standards persist.

  9. Stromal-epithelial dynamics in response to fractionated radiotherapy

    NASA Astrophysics Data System (ADS)

    Qayyum, Muqeem Abdul

    Radiotherapy is central to the management of a number of human cancers, either as an adjuvant or primary treatment modality. The principal objective in irradiating tumors is to permanently inhibit their proliferative ability. More than half of all malignancies are primarily treated with radiation, but the heterotypic nature of tumor cells greatly complicates their response to radiotherapy. The need for reliable parameters to predict tumor and normal tissue response to radiation is therefore a prime concern of clinical oncology. Post-operative radiotherapy has commonly been used for early stage breast cancer to treat residual disease. There is continued debate as to what might be the proper dose per fraction as well as the total dose of radiation that needs to be prescribed to prevent disease recurrence. Countries outside the US have adopted increased dose fractionation (i.e., hypofractionation) schemes for early stage breast cancer as a standard of practice; however there is a lack of confidence in these approaches in the United States. The tumor microenvironment plays a significant role in regulating the progression of carcinomas, although the mechanisms are not entirely clear. The primary objective of this work was to characterize, through mechanobiological and radiobiological modeling, a test bed for radiotherapy fractionation techniques assessment. Our goal is to understand how the tumor microenvironment responds to dose fractionation schemes for Breast Conserving Therapy (BCT). Although carcinomas are the major concern for oncology, in this project, the goal is to understand how the stromal microenvironment influences behavior of the cancer cell populations. By classifying 3-D cellular co-cultures as having a reactive or quiescent stroma using the mechanobiology profile (culture stiffness,cellular activation, differentiation, and proliferation) we aim to differentiate the effectiveness of various fractionation schemes. The benefits of understanding heterotypic

  10. Long-term outcomes of late course accelerated hyper-fractionated radiotherapy for localized esophageal carcinoma in Mainland China: a meta-analysis.

    PubMed

    Zhang, Y W; Chen, L; Bai, Y; Zheng, X

    2011-09-01

    Published data on the long-term survival results of patients with localized esophageal carcinoma receiving late course accelerated hyper-fractionated radiotherapy (LCAF RT) versus conventional fractionated radiotherapy (CF RT) are inconclusive. In order to derive a more precise estimation of the both treatment-regimes, a meta-analysis based on systematic review of published articles was performed. A meta-analysis was performed using trials identified through Pubmed and Chinese national knowledge infrastructure. Results in 5-year survival and 5-year local control were collected from randomized trials comparing LCAF RT with CF RT. Review Manager (The Cochrane Collaboration, Oxford, England) and Stata software (Stata Corporation, College Station, TX, USA) were used for data management. A total of 11 trials were involved in this analysis with 572 cases and 567 controls. Our results showed that LCAF RT, compared with CF RT, significantly improved the 5-year survival (odds ratio [OR]= 2.93, 95% confidence interval [CI]: 2.15-4.00, P < 0.00001) and 5-year local control (OR = 3.96, 95% CI: 2.91-5.38, P < 0.00001). LCAF RT was more therapeutically beneficial than CF RT in the localized esophageal carcinoma. © 2011 Copyright the Authors. Journal compilation © 2011, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

  11. Review on heavy ion radiotherapy facilities and related ion sources (invited)a)

    NASA Astrophysics Data System (ADS)

    Kitagawa, A.; Fujita, T.; Muramatsu, M.; Biri, S.; Drentje, A. G.

    2010-02-01

    Heavy ion radiotherapy awakens worldwide interest recently. The clinical results obtained by the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan have clearly demonstrated the advantages of carbon ion radiotherapy. Presently, there are four facilities for heavy ion radiotherapy in operation, and several new facilities are under construction or being planned. The most common requests for ion sources are a long lifetime and good stability and reproducibility. Sufficient intensity has been achieved by electron cyclotron resonance ion sources at the present facilities.

  12. Randomized Phase III Noninferiority Study Comparing Two Radiotherapy Fractionation Schedules in Patients With Low-Risk Prostate Cancer.

    PubMed

    Lee, W Robert; Dignam, James J; Amin, Mahul B; Bruner, Deborah W; Low, Daniel; Swanson, Gregory P; Shah, Amit B; D'Souza, David P; Michalski, Jeff M; Dayes, Ian S; Seaward, Samantha A; Hall, William A; Nguyen, Paul L; Pisansky, Thomas M; Faria, Sergio L; Chen, Yuhchyau; Koontz, Bridget F; Paulus, Rebecca; Sandler, Howard M

    2016-07-10

    Conventional radiotherapy (C-RT) treatment schedules for patients with prostate cancer typically require 40 to 45 treatments that take place from > 8 to 9 weeks. Preclinical and clinical research suggest that hypofractionation-fewer treatments but at a higher dose per treatment-may produce similar outcomes. This trial was designed to assess whether the efficacy of a hypofractionated radiotherapy (H-RT) treatment schedule is no worse than a C-RT schedule in men with low-risk prostate cancer. A total of 1,115 men with low-risk prostate cancer were randomly assigned 1:1 to C-RT (73.8 Gy in 41 fractions over 8.2 weeks) or to H-RT (70 Gy in 28 fractions over 5.6 weeks). This trial was designed to establish (with 90% power and an α of .05) that treatment with H-RT results in 5-year disease-free survival (DFS) that is not worse than C-RT by more than 7.65% (H-RT/C-RT hazard ratio [HR] < 1.52). A total of 1,092 men were protocol eligible and had follow-up information; 542 patients were assigned to C-RT and 550 to H-RT. Median follow-up was 5.8 years. Baseline characteristics were not different according to treatment assignment. The estimated 5-year DFS was 85.3% (95% CI, 81.9 to 88.1) in the C-RT arm and 86.3% (95% CI, 83.1 to 89.0) in the H-RT arm. The DFS HR was 0.85 (95% CI, 0.64 to 1.14), and the predefined noninferiority criterion that required that DFS outcomes be consistent with HR < 1.52 was met (P < .001). Late grade 2 and 3 GI and genitourinary adverse events were increased (HR, 1.31 to 1.59) in patients who were treated with H-RT. In men with low-risk prostate cancer, the efficacy of 70 Gy in 28 fractions over 5.6 weeks is not inferior to 73.8 Gy in 41 fractions over 8.2 weeks, although an increase in late GI/genitourinary adverse events was observed in patients treated with H-RT. © 2016 by American Society of Clinical Oncology.

  13. Accelerated hyperfractionated intensity-modulated radiotherapy for recurrent/unresectable rectal cancer in patients with previous pelvic irradiation: results of a phase II study.

    PubMed

    Cai, Gang; Zhu, Ji; Hu, Weigang; Zhang, Zhen

    2014-12-11

    This study was conducted to investigate the local effects and toxicity of accelerated hyperfractionated intensity-modulated radiotherapy for recurrent/unresectable rectal cancer in patients with previous pelvic irradiation. Twenty-two patients with recurrent/unresectable rectal cancer who previously received pelvic irradiation were enrolled in our single-center trial between January 2007 and August 2012. Reirradiation was scheduled for up to 39 Gy in 30 fractions using intensity-modulated radiotherapy plans. The dose was delivered via a hyperfractionation schedule of 1.3 Gy twice daily. Patient follow-up was performed by clinical examination, CT/MRI, or PET/CT every 3 months for the first 2 years and every 6 months thereafter. Tumor response was evaluated 1 month after reirradiation by CT/MRI based on the RECIST criteria. Adverse events were assessed using the National Cancer Institute (NCI) common toxicity criteria (version 3.0). The median time from the end of the initial radiation therapy to reirradiation was 30 months (range, 18-93 months). Overall local responses were observed in 9 patients (40.9%). None of the patients achieved a complete response (CR), and 9 patients (40.9%) had a partial response (PR). Thirteen patients failed to achieve a clinical response: 12 (54.5%) presented with stable disease (SD) and 1 (4.5%) with progressive disease (PD). Among all the patients who underwent reirradiation, partial or complete symptomatic relief was achieved in 6 patients (27.3%) and 13 patients (59.1%), respectively. Grade 4 acute toxicity and treatment-related deaths were not observed. The following grade 3 acute toxicities were observed: diarrhea (2 patients, 9.1%), cystitis (1 patient, 4.5%), dermatitis (1 patient, 4.5%), and intestinal obstruction (1 patient, 4.5%). Late toxicity was infrequent. Chronic severe diarrhea, small bowel obstruction, and dysuria were observed in 2 (9.1%), 1 (4.5%) and 2 (9.1%) of the patients, respectively. This study showed that

  14. HEATHER - HElium Ion Accelerator for RadioTHERapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taylor, Jordan; Edgecock, Thomas; Green, Stuart

    2017-05-01

    A non-scaling fixed field alternating gradient (nsFFAG) accelerator is being designed for helium ion therapy. This facility will consist of 2 superconducting rings, treating with helium ions (He²⁺ ) and image with hydrogen ions (H + 2 ). Currently only carbon ions are used to treat cancer, yet there is an increasing interest in the use of lighter ions for therapy. Lighter ions have reduced dose tail beyond the tumour compared to carbon, caused by low Z secondary particles produced via inelastic nuclear reactions. An FFAG approach for helium therapy has never been previously considered. Having demonstrated isochronous acceleration frommore » 0.5 MeV to 900 MeV, we now demonstrate the survival of a realistic beam across both stages.« less

  15. Vrx: a verify-record system for radiotherapy.

    PubMed

    Dickof, P; Morris, P; Getz, D

    1984-01-01

    A system of computer programs has been created to allow the entry of radiotherapy treatment details as defined by the physician, the verification of the machine parameters at every treatment, and the recording of the entire course of treatment. Various utility programs are available to simplify the use and maintenance of the system. The majority of the code is written in FORTRAN-77, the remainder in MACRO-11. The system has been implemented on a PDP 11/60 minicomputer for use with a Mevatron linear accelerator, the implementation required minor hardware changes to the accelerator.

  16. Radiotherapy of oral malignant melanomas in dogs.

    PubMed

    Blackwood, L; Dobson, J M

    1996-07-01

    To evaluate response to radiotherapy in dogs with oral malignant melanomas. Clinical trial. 36 dogs with histologically confirmed oral malignant melanomas. The prescribed radiation dose was 36 Gy given in 4 fractions of 9 Gy at 7-day intervals. The primary radiation source was a linear accelerator. In 25 of 36 dogs, complete remission was achieved, and in 9 dogs, partial remission was achieved. Recurrence of the primary tumor was the cause of euthanasia of 4 dogs. Twenty-one dogs were euthanatized because of metastasis. Radiotherapy was an effective palliative treatment for the primary tumor in dogs with oral malignant melanomas. However, rapid development of metastatic disease remained a major challenge.

  17. Development of an ultrasmall C-band linear accelerator guide for a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head.

    PubMed

    Kamino, Yuichiro; Miura, Sadao; Kokubo, Masaki; Yamashita, Ichiro; Hirai, Etsuro; Hiraoka, Masahiro; Ishikawa, Junzo

    2007-05-01

    We are developing a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head. It is capable of pursuing irradiation and delivering irradiation precisely with the help of an agile moving x-ray head on the gimbals. Requirements for the accelerator guide were established, system design was developed, and detailed design was conducted. An accelerator guide was manufactured and basic beam performance and leakage radiation from the accelerator guide were evaluated at a low pulse repetition rate. The accelerator guide including the electron gun is 38 cm long and weighs about 10 kg. The length of the accelerating structure is 24.4 cm. The accelerating structure is a standing wave type and is composed of the axial-coupled injector section and the side-coupled acceleration cavity section. The injector section is composed of one prebuncher cavity, one buncher cavity, one side-coupled half cavity, and two axial coupling cavities. The acceleration cavity section is composed of eight side-coupled nose reentrant cavities and eight coupling cavities. The electron gun is a diode-type gun with a cerium hexaboride (CeB6) direct heating cathode. The accelerator guide can be operated without any magnetic focusing device. Output beam current was 75 mA with a transmission efficiency of 58%, and the average energy was 5.24 MeV. Beam energy was distributed from 4.95 to 5.6 MeV. The beam profile, measured 88 mm from the beam output hole on the axis of the accelerator guide, was 0.7 mm X 0.9 mm full width at half maximum (FWHM) width. The beam loading line was 5.925 (MeV)-Ib (mA) X 0.00808 (MeV/mA), where Ib is output beam current. The maximum radiation leakage of the accelerator guide at 100 cm from the axis of the accelerator guide was calculated as 0.33 cGy/min at the rated x-ray output of 500 cGy/min from the measured value. This leakage requires no radiation shielding for the accelerator guide itself per IEC 60601-2-1.

  18. Improving Dose Determination Accuracy in Nonstandard Fields of the Varian TrueBeam Accelerator

    NASA Astrophysics Data System (ADS)

    Hyun, Megan A.

    In recent years, the use of flattening-filter-free (FFF) linear accelerators in radiation-based cancer therapy has gained popularity, especially for hypofractionated treatments (high doses of radiation given in few sessions). However, significant challenges to accurate radiation dose determination remain. If physicists cannot accurately determine radiation dose in a clinical setting, cancer patients treated with these new machines will not receive safe, accurate and effective treatment. In this study, an extensive characterization of two commonly used clinical radiation detectors (ionization chambers and diodes) and several potential reference detectors (thermoluminescent dosimeters, plastic scintillation detectors, and alanine pellets) has been performed to investigate their use in these challenging, nonstandard fields. From this characterization, reference detectors were identified for multiple beam sizes, and correction factors were determined to improve dosimetric accuracy for ionization chambers and diodes. A validated computational (Monte Carlo) model of the TrueBeam(TM) accelerator, including FFF beam modes, was also used to calculate these correction factors, which compared favorably to measured results. Small-field corrections of up to 18 % were shown to be necessary for clinical detectors such as microionization chambers. Because the impact of these large effects on treatment delivery is not well known, a treatment planning study was completed using actual hypofractionated brain, spine, and lung treatments that were delivered at the UW Carbone Cancer Center. This study demonstrated that improperly applying these detector correction factors can have a substantial impact on patient treatments. This thesis work has taken important steps toward improving the accuracy of FFF dosimetry through rigorous experimentally and Monte-Carlo-determined correction factors, the validation of an important published protocol (TG-51) for use with FFF reference fields, and a

  19. Dosimetric and geometric evaluation of a hybrid strategy of offline adaptive planning and online image guidance for prostate cancer radiotherapy.

    PubMed

    Liu, Han; Wu, Qiuwen

    2011-08-07

    For prostate cancer patients, online image-guided (IG) radiotherapy has been widely used in clinic to correct the translational inter-fractional motion at each treatment fraction. For uncertainties that cannot be corrected online, such as rotation and deformation of the target volume, margins are still required to be added to the clinical target volume (CTV) for the treatment planning. Offline adaptive radiotherapy has been implemented to optimize the treatment for each individual patient based on the measurements at early stages of treatment process. It has been shown that offline adaptive radiotherapy can effectively reduce the required margin. Recently a hybrid strategy of offline adaptive replanning and online IG was proposed and the geometric evaluation was performed. It was found that the planning margins can further be reduced by 1-2 mm compared to online IG only strategy. The purpose of this study was to investigate the dosimetric benefits of such a hybrid strategy on the target and organs at risk. A total of 420 repeated helical computed tomography scans from 28 patients were included in the study. Both low-risk patients (LRP, CTV = prostate) and intermediate-risk patients (IRP, CTV = prostate + seminal vesicles, SV) were included in the simulation. Two registration methods, based on center-of-mass shift of prostate only and prostate plus SV, were performed for IRP. The intensity-modulated radiotherapy was used in the simulation. Criteria on both cumulative and fractional doses were evaluated. Furthermore, the geometric evaluation was extended to investigate the optimal number of fractions necessary to construct the internal target volume (ITV) for the hybrid strategy. The dosimetric margin improvement was smaller than its geometric counterpart and was in the range of 0-1 mm. The optimal number of fractions necessary for the ITV construction is 2 for LRPs and 3-4 for IRPs in a hypofractionation protocol. A new cumulative index of target volume was proposed

  20. Sci—Fri PM: Dosimetry—06: Commissioning of a 3D patient specific QA system for hypofractionated prostate treatments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rivest, R; Venkataraman, S; McCurdy, B

    The objective of this work is to commission the 6MV-SRS beam model in COMPASS (v2.1, IBA-Dosimetry) and validate its use for patient specific QA of hypofractionated prostate treatments. The COMPASS system consists of a 2D ion chamber array (MatriXX{sup Evolution}), an independent gantry angle sensor and associated software. The system can either directly calculate or reconstruct (using measured detector responses) a 3D dose distribution on the patient CT dataset for plan verification. Beam models are developed and commissioned in the same manner as a beam model is commissioned in a standard treatment planning system. Model validation was initially performed bymore » comparing both COMPASS calculations and reconstructions to measured open field beam data. Next, 10 hypofractionated prostate RapidArc plans were delivered to both the COMPASS system and a phantom with ion chamber and film inserted. COMPASS dose distributions calculated and reconstructed on the phantom CT dataset were compared to the chamber and film measurements. The mean (± standard deviation) difference between COMPASS reconstructed dose and ion chamber measurement was 1.4 ± 1.0%. The maximum discrepancy was 2.6%. Corresponding values for COMPASS calculation were 0.9 ± 0.9% and 2.6%, respectively. The average gamma agreement index (3%/3mm) for COMPAS reconstruction and film was 96.7% and 95.3% when using 70% and 20% dose thresholds, respectively. The corresponding values for COMPASS calculation were 97.1% and 97.1%, respectively. Based on our results, COMPASS can be used for the patient specific QA of hypofractionated prostate treatments delivered with the 6MV-SRS beam.« less

  1. Hypofractionated radiosurgery for intact or resected brain metastases: defining the optimal dose and fractionation.

    PubMed

    Eaton, Bree R; Gebhardt, Brian; Prabhu, Roshan; Shu, Hui-Kuo; Curran, Walter J; Crocker, Ian

    2013-06-07

    Hypofractionated Radiosurgery (HR) is a therapeutic option for delivering partial brain radiotherapy (RT) to large brain metastases or resection cavities otherwise not amenable to single fraction radiosurgery (SRS). The use, safety and efficacy of HR for brain metastases is not well characterized and the optimal RT dose-fractionation schedule is undefined. Forty-two patients treated with HR in 3-5 fractions for 20 (48%) intact and 22 (52%) resected brain metastases with a median maximum dimension of 3.9 cm (0.8-6.4 cm) between May 2008 and August 2011 were reviewed. Twenty-two patients (52%) had received prior radiation therapy. Local (LC), intracranial progression free survival (PFS) and overall survival (OS) are reported and analyzed for relationship to multiple RT variables through Cox-regression analysis. The most common dose-fractionation schedules were 21 Gy in 3 fractions (67%), 24 Gy in 4 fractions (14%) and 30 Gy in 5 fractions (12%). After a median follow-up time of 15 months (range 2-41), local failure occurred in 13 patients (29%) and was a first site of failure in 6 patients (14%). Kaplan-Meier estimates of 1 year LC, intracranial PFS, and OS are: 61% (95% CI 0.53 - 0.70), 55% (95% CI 0.47 - 0.63), and 73% (95% CI 0.65 - 0.79), respectively. Local tumor control was negatively associated with PTV volume (p = 0.007) and was a significant predictor of OS (HR 0.57, 95% CI 0.33 - 0.98, p = 0.04). Symptomatic radiation necrosis occurred in 3 patients (7%). HR is well tolerated in both new and recurrent, previously irradiated intact or resected brain metastases. Local control is negatively associated with PTV volume and a significant predictor of overall survival, suggesting a need for dose escalation when using HR for large intracranial lesions.

  2. Toxicity and outcome of a phase II trial of taxane-based neoadjuvant chemotherapy and 3-dimensional, conformal, accelerated radiotherapy in locally advanced nonsmall cell lung cancer.

    PubMed

    Rojas, Ana M; Lyn, Basil E; Wilson, Elena M; Williams, Frances J; Shah, Nihal; Dickson, Jeanette; Saunders, Michele I

    2006-09-15

    The objective of this study was to evaluate prospectively the acute and late adverse effects of taxane/carboplatin neoadjuvant chemotherapy and 3-dimensional, conformal radiotherapy in patients with locally advanced nonsmall cell lung cancer (NSCLC). Forty-two patients were entered into a nonrandomized Phase II study of continuous, hyperfractionated, accelerated radiotherapy (CHART) week-end less (CHARTWEL) to a dose of 60 grays (Gy). Three cycles of chemotherapy were given over 9 weeks before radiotherapy. Dose escalation with paclitaxel was from 150 mg/m2 to 225 mg/m2. Systemic toxicity to chemotherapy was monitored throughout. Radiation-induced, early, adverse effects were assessed during the first 9 weeks from the start of radiotherapy, and late effects were assessed from 3 months onward. Overall survival, disease-free survival, and locoregional tumor control also were monitored. Twenty percent of patients failed to receive chemotherapy as planned, primarily because of neutropenia. The incidence of Dische Dictionary Grade >or=2 and Grade >or=3 dysphagia was 57.5% and 10%, respectively, with an average duration of 1.2 weeks and 1.5 days, respectively. By 9 weeks, <3% of patients were symptomatic; and, eventually, all acute reactions were healed, and there has been no evidence of consequential damage. At 6 months, the actuarial incidence of moderate-to-severe pneumonitis was 10%. During this time, all patients were free of severe pulmonary complications. Actuarial estimates of Grade >or=2 late lung dysfunction were 3% at 1 year, 10% at 2 years, and remained at this level thereafter. The actuarial 3-year locoregional control and overall survival rates were 54% and 45%, respectively. Neoadjuvant chemotherapy followed by 3-dimensional, conformal CHARTWEL 60-Gy radiotherapy in patients with advanced NSCLC was feasible and was tolerated well. Historic comparisons indicated that locoregional tumor control is not compromised by the use of conformal techniques. (c) 2006

  3. Quantification of intra-fraction motion in breast radiotherapy using supine magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    van Heijst, Tristan C. F.; Philippens, Mariëlle E. P.; Charaghvandi, Ramona K.; den Hartogh, Mariska D.; Lagendijk, Jan J. W.; Desirée van den Bongard, H. J. G.; van Asselen, Bram

    2016-02-01

    In early-stage breast-cancer patients, accelerated partial-breast irradiation techniques (APBI) and hypofractionation are increasingly implemented after breast-conserving surgery (BCS). For a safe and effective radiation therapy (RT), the influence of intra-fraction motion during dose delivery becomes more important as associated fraction durations increase and targets become smaller. Current image-guidance techniques are insufficient to characterize local target movement in high temporal and spatial resolution for extended durations. Magnetic resonance imaging (MRI) can provide high soft-tissue contrast, allow fast imaging, and acquire images during longer periods. The goal of this study was to quantify intra-fraction motion using MRI scans from 21 breast-cancer patients, before and after BCS, in supine RT position, on two time scales. High-temporal 2-dimensional (2D) MRI scans (cine-MRI), acquired every 0.3 s during 2 min, and three 3D MRI scans, acquired over 20 min, were performed. The tumor (bed) and whole breast were delineated on 3D scans and delineations were transferred to the cine-MRI series. Consecutive scans were rigidly registered and delineations were transformed accordingly. Motion in sub-second time-scale (derived from cine-MRI) was generally regular and limited to a median of 2 mm. Infrequently, large deviations were observed, induced by deep inspiration, but these were temporary. Movement on multi-minute scale (derived from 3D MRI) varied more, although medians were restricted to 2.2 mm or lower. Large whole-body displacements (up to 14 mm over 19 min) were sparsely observed. The impact of motion on standard RT techniques is likely small. However, in novel hypofractionated APBI techniques, whole-body shifts may affect adequate RT delivery, given the increasing fraction durations and smaller targets. Motion management may thus be required. For this, on-line MRI guidance could be provided by a hybrid MRI/RT modality, such as the

  4. Assessment of quality of life in patients treated with accelerated radiotherapy for laryngeal and hypopharyngeal carcinomas.

    PubMed

    Allal, A S; Dulguerov, P; Bieri, S; Lehmann, W; Kurtz, J M

    2000-05-01

    This study was conducted to evaluate quality of life (QOL) and functional outcome in patients with carcinomas of the larynx and hypopharynx treated with accelerated radiotherapy (RT). Between January 1991 and September 1996, 21 patients treated with accelerated concomitant boost RT schedule (69.9 Gy in 5. 5 weeks) for laryngeal (n = 10) or hypopharyngeal (n = 11) carcinomas and who remained free of disease at 1-year minimum follow-up were evaluated. The functional outcome was assessed by the subjective Performance Status Scale for Head and Neck cancer (PSSHN) and general QOL by the European Organization for Research and Treatment of Cancer Core QOL questionnaire (EORTC QLQ-C30). The median length of follow-up was 37 months (range, 13 to 75). The PSSHN scores were 89, 84, and 86, respectively, for eating in public, understandability of speech and normalcy of diet (100 = normal function). Significantly lower scores for understandability of speech were observed in patients with advanced and laryngeal carcinomas. Normalcy of diet was affected negatively by the severity of xerostomia. All mean functional scale scores of the EORTC QLQ-C30 module were 20% to 25% below the higher score. Most of these scale scores were significantly affected by the severity of xerostomia. Patients treated with concomitant boost RT for laryngeal and hypopharyngeal carcinomas appear to have similar QOL and functional outcome to those reported for patients treated with conventional or hyperfractionated RT. As expected, many QOL scales were affected by the severity of xero- stomia.

  5. Gradient of γ rays and β particles irradiation’s energy produced by accelerator and its use in radiotherapy of cancer diseases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kastrati, Labinot, E-mail: labinotkastrati82@gmail.com; Nafezi, Gazmend, E-mail: gazmend-nafezi@hotmail.com; Shehi, Gëzim, E-mail: gezimshehi@yahoo.com

    2016-03-25

    The Ionising irradiations used mostly in the treatment of tumoral diseases are: X, γ, β and e irradiations. The discussion will be about radiations, produced in accelerators, with photon energy 6 MV and 15 MV and electron energy from 5 MeV to 15 MeV. Due to the differences between γ and β radiations, their absorbtion in living tissues will be different. It is important to know, the absorption performance before and after the electronic equilibrium. For these purposes, we’ve use the function of dose gradient, for irradiations γ and β. It represents the velocity of dose change as a function of depthmore » in tissue. From skin to maximum dose value, the increase of G-function is more accentuated for γ-rays than for β-particles, while after that the G-function decreasing is less sharp for γ-rays, while for β-particles, it is almost promptly. This fact allow us to use in radiotherapy, not only γ-rays but β-particles, too. The lasts, represents, a much more efficient tool, especially in terms of radiation protection, of health adjacent tissues and organs. Finally, we’ll to discus, about the advantages in terms of radiation protection of both, γ-rays and β-particles used in radiotherapy.« less

  6. The impact of toceranib, piroxicam and thalidomide with or without hypofractionated radiation therapy on clinical outcome in dogs with inflammatory mammary carcinoma.

    PubMed

    Rossi, F; Sabattini, S; Vascellari, M; Marconato, L

    2018-05-27

    In dogs, inflammatory mammary carcinoma is a clinicopathological entity characterized by rapid progression and aggressive behavior from onset of disease. Reported median survival time is short, with no effective treatment options. The aims of this prospective, noncontrolled clinical trial were to investigate outcome variables and safety profile of toceranib, thalidomide and piroxicam with or without hypofractionated radiation therapy in dogs with measurable histologically confirmed inflammatory mammary carcinoma that underwent a complete staging. Eighteen dogs were enrolled: 14 received medical treatment, and 4 were treated with hypofractionated radiation therapy and medical therapy. Overall, median time to progression was 34 days and median survival time was 109 days. In dogs treated with medical therapy, overall response rate was 21%, and clinical benefit rate (CBR) was 64%; median time to progression was 28 days and median survival time was 59 days. In dogs receiving medical therapy and undergoing radiation therapy, overall response rate and clinical benefit rate were 100%, with significantly longer time to progression (156 days) and survival time (180 days). Overall, treatment was well tolerated, with mild gastrointestinal and dermatological adverse events. Although the optimal treatment to this disease remains uncertain, the current approach consisting of systemic anti-angiogenic drugs with or without hypofractionated radiation therapy, provided clinical benefit in a significant proportion of dogs and should, therefore, be further explored. © 2018 John Wiley & Sons Ltd.

  7. Intensified hyperfractionated accelerated radiotherapy limits the additional benefit of simultaneous chemotherapy--results of a multicentric randomized German trial in advanced head-and-neck cancer.

    PubMed

    Staar, S; Rudat, V; Stuetzer, H; Dietz, A; Volling, P; Schroeder, M; Flentje, M; Eckel, H E; Mueller, R P

    2001-08-01

    To demonstrate the efficacy of radiochemotherapy (RCT) as the first choice of treatment for advanced unresectable head-and-neck cancer. To prove an expected benefit of simultaneously given chemotherapy, a two-arm randomized study with hyperfractionated accelerated radiochemotherapy (HF-ACC-RCT) vs. hyperfractionated accelerated radiotherapy (HF-ACC-RT) was initiated. The primary endpoint was 1-year survival with local control (SLC). Patients with Stage III and IV (UICC) unresectable oro- and hypopharyngeal carcinomas were randomized for HF-ACC-RCT with 2 cycles of 5-FU (600 mg/m(2)/day)/carboplatinum (70 mg/m(2)) on days 1--5 and 29--33 (arm A) or HF-ACC-RT alone (arm B). In both arms, there was a second randomization for testing the effect of prophylactically given G-CSF (263 microg, days 15--19) on mucosal toxicity. Total RT dose in both arms was 69.9 Gy in 38 days, with a concomitant boost regimen (weeks 1--3: 1.8 Gy/day, weeks 4 and 5: b.i.d. RT with 1.8 Gy/1.5 Gy). Between July 1995 and May 1999, 263 patients were randomized (median age 56 years; 96% Stage IV tumors, 4% Stage III tumors). This analysis is based on 240 patients: 113 patients with RCT and 127 patients with RT, qualified for protocol and starting treatment. There were 178 oropharyngeal and 62 hypopharyngeal carcinomas. Treatment was tolerable in both arms, with a higher mucosal toxicity after RCT. Restaging showed comparable nonsignificant different CR + PR rates of 92.4% after RCT and 87.9% after RT (p = 0.29). After a median observed time of 22.3 months, l- and 2-year local-regional control (LRC) rates were 69% and 51% after RCT and 58% and 45% after RT (p = 0.14). There was a significantly better 1-year SLC after RCT (58%) compared with RT (44%, p = 0.05). Patients with oropharyngeal carcinomas showed significantly better SLC after RCT (60%) vs. RT (40%, p = 0.01); the smaller group of hypopharyngeal carcinomas had no statistical benefit of RCT (p = 0.84). For both tumor locations

  8. Integer programming for improving radiotherapy treatment efficiency.

    PubMed

    Lv, Ming; Li, Yi; Kou, Bo; Zhou, Zhili

    2017-01-01

    Patients received by radiotherapy departments are diverse and may be diagnosed with different cancers. Therefore, they need different radiotherapy treatment plans and thus have different needs for medical resources. This research aims to explore the best method of scheduling the admission of patients receiving radiotherapy so as to reduce patient loss and maximize the usage efficiency of service resources. A mix integer programming (MIP) model integrated with special features of radiotherapy is constructed. The data used here is based on the historical data collected and we propose an exact method to solve the MIP model. Compared with the traditional First Come First Served (FCFS) method, the new method has boosted patient admission as well as the usage of linear accelerators (LINAC) and beds. The integer programming model can be used to describe the complex problem of scheduling radio-receiving patients, to identify the bottleneck resources that hinder patient admission, and to obtain the optimal LINAC-bed radio under the current data conditions. Different management strategies can be implemented by adjusting the settings of the MIP model. The computational results can serve as a reference for the policy-makers in decision making.

  9. A review of ion sources for medical accelerators (invited)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muramatsu, M.; Kitagawa, A.

    2012-02-15

    There are two major medical applications of ion accelerators. One is a production of short-lived isotopes for radionuclide imaging with positron emission tomography and single photon emission computer tomography. Generally, a combination of a source for negative ions (usually H- and/or D-) and a cyclotron is used; this system is well established and distributed over the world. Other important medical application is charged-particle radiotherapy, where the accelerated ion beam itself is being used for patient treatment. Two distinctly different methods are being applied: either with protons or with heavy-ions (mostly carbon ions). Proton radiotherapy for deep-seated tumors has become widespreadmore » since the 1990s. The energy and intensity are typically over 200 MeV and several 10{sup 10} pps, respectively. Cyclotrons as well as synchrotrons are utilized. The ion source for the cyclotron is generally similar to the type for production of radioisotopes. For a synchrotron, one applies a positive ion source in combination with an injector linac. Carbon ion radiotherapy awakens a worldwide interest. About 6000 cancer patients have already been treated with carbon beams from the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan. These clinical results have clearly verified the advantages of carbon ions. Heidelberg Ion Therapy Center and Gunma University Heavy Ion Medical Center have been successfully launched. Several new facilities are under commissioning or construction. The beam energy is adjusted to the depth of tumors. It is usually between 140 and 430 MeV/u. Although the beam intensity depends on the irradiation method, it is typically several 10{sup 8} or 10{sup 9} pps. Synchrotrons are only utilized for carbon ion radiotherapy. An ECR ion source supplies multi-charged carbon ions for this requirement. Some other medical applications with ion beams attract developer's interests. For example, the several types of

  10. Repeated Positron Emission Tomography-Computed Tomography and Perfusion-Computed Tomography Imaging in Rectal Cancer: Fluorodeoxyglucose Uptake Corresponds With Tumor Perfusion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Janssen, Marco H.M., E-mail: marco.janssen@maastro.nl; Aerts, Hugo J.W.L.; Buijsen, Jeroen

    2012-02-01

    Purpose: The purpose of this study was to analyze both the intratumoral fluorodeoxyglucose (FDG) uptake and perfusion within rectal tumors before and after hypofractionated radiotherapy. Methods and Materials: Rectal cancer patients, referred for preoperative hypofractionated radiotherapy (RT), underwent FDG-positron emission tomography (PET)-computed tomography (CT) and perfusion-CT (pCT) imaging before the start of hypofractionated RT and at the day of the last RT fraction. The pCT-images were analyzed using the extended Kety model, quantifying tumor perfusion with the pharmacokinetic parameters K{sup trans}, v{sub e}, and v{sub p}. The mean and maximum FDG uptake based on the standardized uptake value (SUV) andmore » transfer constant (K{sup trans}) within the tumor were correlated. Also, the tumor was subdivided into eight subregions and for each subregion the mean and maximum SUVs and K{sup trans} values were assessed and correlated. Furthermore, the mean FDG uptake in voxels presenting with the lowest 25% of perfusion was compared with the FDG uptake in the voxels with the 25% highest perfusion. Results: The mean and maximum K{sup trans} values were positively correlated with the corresponding SUVs ({rho} = 0.596, p = 0.001 and {rho} = 0.779, p < 0.001). Also, positive correlations were found for K{sup trans} values and SUVs within the subregions (mean, {rho} = 0.413, p < 0.001; and max, {rho} = 0.540, p < 0.001). The mean FDG uptake in the 25% highest-perfused tumor regions was significantly higher compared with the 25% lowest-perfused regions (10.6% {+-} 5.1%, p = 0.017). During hypofractionated radiotherapy, stable mean (p = 0.379) and maximum (p = 0.280) FDG uptake levels were found, whereas the mean (p = 0.040) and maximum (p = 0.003) K{sup trans} values were found to significantly increase. Conclusion: Highly perfused rectal tumors presented with higher FDG-uptake levels compared with relatively low perfused tumors. Also, intratumor regions with a

  11. Normal tissue toxicity after small field hypofractionated stereotactic body radiation.

    PubMed

    Milano, Michael T; Constine, Louis S; Okunieff, Paul

    2008-10-31

    Stereotactic body radiation (SBRT) is an emerging tool in radiation oncology in which the targeting accuracy is improved via the detection and processing of a three-dimensional coordinate system that is aligned to the target. With improved targeting accuracy, SBRT allows for the minimization of normal tissue volume exposed to high radiation dose as well as the escalation of fractional dose delivery. The goal of SBRT is to minimize toxicity while maximizing tumor control. This review will discuss the basic principles of SBRT, the radiobiology of hypofractionated radiation and the outcome from published clinical trials of SBRT, with a focus on late toxicity after SBRT. While clinical data has shown SBRT to be safe in most circumstances, more data is needed to refine the ideal dose-volume metrics.

  12. An online x-ray based position validation system for prostate hypofractionated radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arumugam, Sankar, E-mail: Sankar.Arumugam@sswahs.nsw.gov.au; Xing, Aitang; Sidhom, Mark

    Purpose: Accurate positioning of the target volume during treatment is paramount for stereotactic body radiation therapy (SBRT). In this work, the authors present the development of an in-house software tool to verify target position with an Elekta-Synergy linear accelerator using kV planar images acquired during treatment delivery. Methods: In-house software, SeedTracker, was developed in MATLAB to perform the following three functions: 1. predict intended seed positions in a planar view perpendicular to any gantry angle, simulating a portal imaging device, from the 3D seed co-ordinates derived from the treatment planning system; 2. autosegment seed positions in kV planar images; andmore » 3. report the position shift based on the seed positions in the projection images. The performance of SeedTracker was verified using a CIRS humanoid phantom (CIRS, VA, USA) implanted with three Civco gold seed markers (Civco, IA, USA) in the prostate. The true positive rate of autosegmentation (TPR{sub seg}) and the accuracy of the software in alerting the user when the isocenter position was outside the tolerance (TPR{sub trig}) were studied. Two-dimensional and 3D static position offsets introduced to the humanoid phantom and 3D dynamic offsets introduced to a gel phantom containing gold seeds were used for evaluation of the system. Results: SeedTracker showed a TPR{sub seg} of 100% in the humanoid phantom for projection images acquired at all angles except in the ranges of 80°–100° and 260°–280° where seeds are obscured by anatomy. This resulted in a TPR{sub trig} of 88% over the entire treatment range for considered 3D static offsets introduced to the phantom. For 2D static offsets where the position offsets were only introduced in the anterior–posterior and lateral directions, the TPR{sub trig} of SeedTracker was limited by both seed detectability and positional offset. SeedTracker showed a false positive trigger in the projection angle range between 130°–170

  13. Quality of radiotherapy services in post-Soviet countries: An IAEA survey.

    PubMed

    Rosenblatt, Eduardo; Fidarova, Elena; Ghosh, Sunita; Zubizarreta, Eduardo; Unterkirhere, Olga; Semikoz, Natalia; Sinaika, Valery; Kim, Viktor; Karamyan, Nerses; Isayev, Isa; Akbarov, Kamal; Lomidze, Darejan; Bondareva, Oksana; Tuzlucov, Piotr; Zardodkhonova, Manzura; Tkachev, Sergey; Kislyakova, Marina; Alimov, Jamshid; Pidlubna, Tetiana; Barton, Michael; Mackillop, William

    2018-04-25

    The quality of radiotherapy services in post-Soviet countries has not yet been studied following a formal methodology. The IAEA conducted a survey using two sets of validated radiation oncology quality indicators (ROIs). Eleven post-Soviet countries were assessed. A coordinator was designated for each country and acted as the liaison between the country and the IAEA. The methodology was a one-time cross-sectional survey using a 58-question tool in Russian. The questionnaire was based on two validated sets of ROIs: for radiotherapy centres, the indicators proposed by Cionini et al., and for data at the country level, the Australasian ROIs. The overall response ratio was 66.3%, but for the Russian Federation, it was 24%. Data were updated on radiotherapy infrastructure and equipment. 256 radiotherapy centres are operating 275 linear accelerators and 337 Cobalt-60 units. 61% of teletherapy machines are older than ten years. Analysis of ROIs revealed significant differences between these countries and radiotherapy practices in the West. Naming, task profile and education programmes of radiotherapy professionals are different than in the West. Most countries need modernization of their radiotherapy infrastructure coupled with adequate staffing numbers and updated education programmes focusing on evidence-based medicine, quality, and safety. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. 30 Years of radiotherapy service in Southern Thailand: workload vs resources.

    PubMed

    Phungrassami, Temsak; Funsian, Amporn; Sriplung, Hutcha

    2013-01-01

    To study the pattern of patient load, personnel and equipment resources from 30-years experience in Southern Thailand. This retrospective study collected secondary data from the Division of Therapeutic Radiology and Oncology and the Songklanagarind Hospital Tumor Registry database, Faculty of Medicine, Prince of Songkla University, during the period of 1982-2012. The number of new patients who had radiation treatment gradually increased from 121 in 1982 to 2,178 in 2011. Shortages of all kinds of personnel were demonstrated as compared to the recommendations, especially in radiotherapy technicians. In 2011, Southern Thailand, with two radiotherapy centers, had 0.44 megavoltage radiotherapy machines (cobalt or linear accelerator) per million of population. This number is suboptimal, but could be managed cost-effectively by prolonging machine operating times during personnel shortages. This study identified a discrepancy between workload and resources in one medical school radiotherapy center in.

  15. Hypofractionated stereotactic radiotherapy (HFSRT) for who grade I anterior clinoid meningiomas (ACM).

    PubMed

    Demiral, Selcuk; Dincoglan, Ferrat; Sager, Omer; Gamsiz, Hakan; Uysal, Bora; Gundem, Esin; Elcim, Yelda; Dirican, Bahar; Beyzadeoglu, Murat

    2016-11-01

    While microsurgical resection plays a central role in the management of ACMs, extensive surgery may be associated with substantial morbidity particularly for tumors in intimate association with critical structures. In this study, we evaluated the use of HFSRT in the management of ACM. A total of 22 patients with ACM were treated using HFSRT. Frameless image guided volumetric modulated arc therapy (VMAT) was performed with a 6 MV linear accelerator (LINAC). The total dose was 25 Gy delivered in five fractions over five consecutive treatment days. Local control (LC) and progression free survival (PFS) rates were calculated using the Kaplan-Meier method. Common Terminology Criteria for Adverse Events, version 4.0 was used in toxicity grading. Out of the total 22 patients, outcomes of 19 patients with at least 36 months of periodic follow-up were assessed. Median patient age was 40 years old (range 24-77 years old). Median follow-up time was 53 months (range 36-63 months). LC and PFS rates were 100 and 89.4 % at 1 and 3 years, respectively. Only two patients (10.5 %) experienced clinical deterioration during the follow-up period. LINAC-based HFSRT offers high rates of LC and PFS for patients with ACMs.

  16. A Phase 2 Trial of Once-Weekly Hypofractionated Breast Irradiation: First Report of Acute Toxicity, Feasibility, and Patient Satisfaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dragun, Anthony E., E-mail: aedrag01@louisville.edu; Quillo, Amy R.; Riley, Elizabeth C.

    2013-03-01

    Purpose: To report on early results of a single-institution phase 2 trial of a 5-fraction, once-weekly radiation therapy regimen for patients undergoing breast-conserving surgery (BCS). Methods and Materials: Patients who underwent BCS for American Joint Committee on Cancer stage 0, I, or II breast cancer with negative surgical margins were eligible to receive whole breast radiation therapy to a dose of 30 Gy in 5 weekly fractions of 6 Gy with or without an additional boost. Elective nodal irradiation was not permitted. There were no restrictions on breast size or the use of cytotoxic chemotherapy for otherwise eligible patients. Patientsmore » were assessed at baseline, treatment completion, and at first posttreatment follow-up to assess acute toxicity (Common Terminology Criteria for Adverse Events, version 3.0) and quality of life (European Organization for Research and Treatment of Cancer QLQ-BR23). Results: Between January and September 2011, 42 eligible patients underwent weekly hypofractionated breast irradiation immediately following BCS (69.0%) or at the conclusion of cytotoxic chemotherapy (31.0%). The rates of grade ≥2 radiation-induced dermatitis, pain, fatigue, and breast edema were 19.0%, 11.9%, 9.5%, and 2.4%, respectively. Only 1 grade 3 toxicity—pain requiring a course of narcotic analgesics—was observed. One patient developed a superficial cellulitis (grade 2), which resolved with the use of oral antibiotics. Patient-reported moderate-to-major breast symptoms (pain, swelling, and skin problems), all decreased from baseline through 1 month, whereas breast sensitivity remained stable over the study period. Conclusions: The tolerance of weekly hypofractionated breast irradiation compares well with recent reports of daily hypofractionated whole-breast irradiation schedules. The regimen appears feasible and cost-effective. Additional follow-up with continued accrual is needed to assess late toxicity, cosmesis, and disease-specific outcomes.« less

  17. Protracted Hypofractionated Radiotherapy for Graves' Ophthalmopathy: A Pilot Study of Clinical and Radiologic Response

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Casimiro de Deus Cardoso, Cejana; Giordani, Adelmo Jose; Borri Wolosker, Angela Maria

    Purpose: To evaluate the clinical and radiologic response of patients with Graves' ophthalmopathy given low-dose orbital radiotherapy (RT) with a protracted fractionation. Methods and Materials: Eighteen patients (36 orbits) received orbital RT with a total dose of 10 Gy, fractionated in 1 Gy once a week over 10 weeks. Of these, 9 patients received steroid therapy as well. Patients were evaluated clinically and radiologically at 6 months after treatment. Clinical response assessment was carried out using three criteria: by physical examination, by a modified clinical activity score, and by a verbal questionnaire considering the 10 most common signs and symptomsmore » of the disease. Radiologic response was assessed by magnetic resonance imaging. Results: Improvement in ocular pain, palpebral edema, visual acuity, and ocular motility was observed in all patients. Significant decrease in symptoms such as tearing (p < 0.001) diplopia (p = 0.008), conjunctival hyperemia (p = 0.002), and ocular grittiness (p = 0.031) also occurred. Magnetic resonance imaging showed decrease in ocular muscle thickness and in the intensity of the T2 sequence signal in the majority of patients. Treatments were well tolerated, and to date no complications from treatment have been observed. There was no statistical difference in clinical and radiologic response between patients receiving RT alone and those receiving RT plus steroid therapy. Conclusion: RT delivered in at a low dose and in a protracted scheme should be considered as a useful therapeutic option for patients with Graves' ophthalmopathy.« less

  18. Long-Term Outcomes From a Prospective Trial of Stereotactic Body Radiotherapy for Low-Risk Prostate Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    King, Christopher R., E-mail: crking@mednet.ucla.edu; Brooks, James D.; Gill, Harcharan

    2012-02-01

    Purpose: Hypofractionated radiotherapy has an intrinsically different normal tissue and tumor radiobiology. The results of a prospective trial of stereotactic body radiotherapy (SBRT) for prostate cancer with long-term patient-reported toxicity and tumor control rates are presented. Methods and Materials: From 2003 through 2009, 67 patients with clinically localized low-risk prostate cancer were enrolled. Treatment consisted of 36.25 Gy in 5 fractions using SBRT with the CyberKnife as the delivery technology. No patient received hormone therapy. Patient self-reported bladder and rectal toxicities were graded on the Radiation Therapy Oncology Group scale (RTOG). Results: Median follow-up was 2.7 years. There were nomore » grade 4 toxicities. Radiation Therapy Oncology Group Grade 3, 2, and 1 bladder toxicities were seen in 3% (2 patients), 5% (3 patients), and 23% (13 patients) respectively. Dysuria exacerbated by urologic instrumentation accounted for both patients with Grade 3 toxicity. Urinary incontinence, complete obstruction, or persistent hematuria was not observed. Rectal Grade 3, 2, and 1 toxicities were seen in 0, 2% (1 patient), and 12.5% (7 patients), respectively. Persistent rectal bleeding was not observed. Low-grade toxicities were substantially less frequent with QOD vs. QD dose regimen (p = 0.001 for gastrointestinal and p = 0.007 for genitourinary). There were two prostate-specific antigen (PSA), biopsy-proven failures with negative metastatic workup. Median PSA at follow-up was 0.5 {+-} 0.72 ng/mL. The 4-year Kaplan-Meier PSA relapse-free survival was 94% (95% confidence interval, 85%-102%). Conclusion: Significant late bladder and rectal toxicities from SBRT for prostate cancer are infrequent. PSA relapse-free survival compares favorably with other definitive treatments. The current evidence supports consideration of stereotactic body radiotherapy among the therapeutic options for localized prostate cancer.« less

  19. Tumor control probability reduction in gated radiotherapy of non-small cell lung cancers: a feasibility study.

    PubMed

    Siochi, R Alfredo; Kim, Yusung; Bhatia, Sudershan

    2014-10-16

    We studied the feasibility of evaluating tumor control probability (TCP) reductions for tumor motion beyond planned gated radiotherapy margins. Tumor motion was determined from cone-beam CT projections acquired for patient setup, intrafraction respiratory traces, and 4D CTs for five non-small cell lung cancer (NSCLC) patients treated with gated radiotherapy. Tumors were subdivided into 1 mm sections whose positions and doses were determined for each beam-on time point. (The dose calculation model was verified with motion phantom measurements.) The calculated dose distributions were used to generate the treatment TCPs for each patient. The plan TCPs were calculated from the treatment planning dose distributions. The treatment TCPs were compared to the plan TCPs for various models and parameters. Calculated doses matched phantom measurements within 0.3% for up to 3 cm of motion. TCP reductions for excess motion greater than 5mm ranged from 1.7% to 11.9%, depending on model parameters, and were as high as 48.6% for model parameters that simulated an individual patient. Repeating the worst case motion for all fractions increased TCP reductions by a factor of 2 to 3, while hypofractionation decreased these reductions by as much as a factor of 3. Treatment motion exceeding gating margins by more than 5 mm can lead to considerable TCP reductions. Appropriate margins for excess motion are recommended, unless applying daily tumor motion verification and adjusting thegating window.

  20. Dosimetric and geometric evaluation of a hybrid strategy of offline adaptive planning and online image guidance for prostate cancer radiotherapy

    PubMed Central

    Liu, Han; Wu, Qiuwen

    2011-01-01

    For prostate cancer patients, online image-guided (IG) radiotherapy has been widely used in clinic to correct the translational inter-fractional motion at each treatment fraction. For uncertainties that cannot be corrected online, such as rotation and deformation of the target volume, margins are still required to be added to the clinical target volume (CTV) for the treatment planning. Offline adaptive radiotherapy has been implemented to optimize the treatment for each individual patient based on the measurements at early stages of treatment process. It has been shown that offline adaptive radiotherapy can effectively reduce the required margin. Recently a hybrid strategy of offline adaptive replanning and online IG was proposed and the geometric evaluation was performed. It was found that the planning margins can be further reduced by 1–2 mm compared to online IG only strategy. The purpose of this study was to investigate the dosimetric benefits of such hybrid strategy on the target and organs at risk (OARs). A total of 420 repeated helical computed tomography (HCT) scans from 28 patients were included in the study. Both low-risk patients (LRP, CTV = prostate) and intermediate-risk patients (IRP, CTV = prostate + seminal vesicles, SV) were included in the simulation. Two registration methods, based on center-of-mass (COM) shift of prostate only and prostate plus SV, were performed for IRP. The intensity modulated radiotherapy (IMRT) was used in the simulation. Criteria on both cumulative dose and fractional doses were evaluated. Furthermore, the geometric evaluation was extended to investigate the optimal number of fractions necessary to construct the internal target volume (ITV) for the hybrid strategy. The dosimetric margin improvement was smaller than its geometric counterpart and was in the range of 0 mm to 1 mm. The optimal number of fractions necessary for the ITV construction is 2 for LRP and 3–4 for IRP in a hypofractionation protocol. A new

  1. Poster — Thur Eve — 28: Enabling trajectory-based radiotherapy on a TrueBeam accelerator with the Eclipse treatment planning system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mullins, J; Asiev, K; DeBlois, F

    2014-08-15

    The TrueBeam linear accelerator platform has a developer's mode which permits the user dynamic control over many of the machine's mechanical and radiation systems. Using this research tool, synchronous couch and gantry motion can be programmed to simulate isocentric treatment with a shortened SAD, with benefits such as smaller projected MLC leaf widths and an increased dose rate. In this work, water tank measurements were used to commission a virtual linear accelerator with an 85 cm SAD in Eclipse, from which several arc-based radiotherapy treatments were generated, including an inverse optimized VMAT delivery. For each plan, the pertinent treatment deliverymore » information was extracted from control points specified in the Eclipse-exported DICOM files using the pydicom package in Python, allowing construction of an XML control file. The dimensions of the jaws and MLC positions, defined for an 85 cm SAD in Eclipse, were scaled for delivery on a conventional SAD linear accelerator, and translational couch motion was added as a function of gantry angle to simulate delivery at 85 cm SAD. Ionization chamber and Gafchromic film measurements were used to compare the radiation delivery to dose calculations in Eclipse. With the exception of the VMAT delivery, ionization chamber measurements agreed within 3.3% of the Eclipse calculations. For the VMAT delivery, the ionization chamber was located in an inhomogeneous region, but gamma evaluation of the Gafchromic film plane resulted in a 94.5% passing rate using criteria of 3 mm/3%. The results indicate that Eclipse calculation infrastructure can be used.« less

  2. Hypo-fractionated radiation, magnetic nanoparticle hyperthermia and a viral immunotherapy treatment of spontaneous canine cancer

    NASA Astrophysics Data System (ADS)

    Hoopes, P. Jack; Moodie, Karen L.; Petryk, Alicia A.; Petryk, James D.; Sechrist, Shawntel; Gladstone, David J.; Steinmetz, Nicole F.; Veliz, Frank A.; Bursey, Alicea A.; Wagner, Robert J.; Rajan, Ashish; Dugat, Danielle; Crary-Burney, Margaret; Fiering, Steven N.

    2017-02-01

    It has recently been shown that cancer treatments such as radiation and hyperthermia, which have conventionally been viewed to have modest immune based anti-cancer effects, may, if used appropriately stimulate a significant and potentially effective local and systemic anti-cancer immune effect (abscopal effect) and improved prognosis. Using eight spontaneous canine cancers (2 oral melanoma, 3 oral amelioblastomas and 1 carcinomas), we have shown that hypofractionated radiation (6 x 6 Gy) and/or magnetic nanoparticle hyperthermia (2 X 43°C / 45 minutes) and/or an immunogenic virus-like nanoparticle (VLP, 2 x 200 μg) are capable of delivering a highly effective cancer treatment that includes an immunogenic component. Two tumors received all three therapeutic modalities, one tumor received radiation and hyperthermia, two tumors received radiation and VLP, and three tumors received only mNP hyperthermia. The treatment regimen is conducted over a 14-day period. All patients tolerated the treatments without complication and have had local and distant tumor responses that significantly exceed responses observed following conventional therapy (surgery and/or radiation). The results suggest that both hypofractionated radiation and hyperthermia have effective immune responses that are enhanced by the intratumoral VLP treatment. Molecular data from these tumors suggest Heat Shock Protein (HSP) 70/90, calreticulin and CD47 are targets that can be exploited to enhance the local and systemic (abscopal effect) immune potential of radiation and hyperthermia cancer treatment.

  3. Radiobiological effectiveness of laser accelerated electrons in comparison to electron beams from a conventional linear accelerator.

    PubMed

    Laschinsky, Lydia; Baumann, Michael; Beyreuther, Elke; Enghardt, Wolfgang; Kaluza, Malte; Karsch, Leonhard; Lessmann, Elisabeth; Naumburger, Doreen; Nicolai, Maria; Richter, Christian; Sauerbrey, Roland; Schlenvoigt, Hans-Peter; Pawelke, Jörg

    2012-01-01

    The notable progress in laser particle acceleration technology promises potential medical application in cancer therapy through compact and cost effective laser devices that are suitable for already existing clinics. Previously, consequences on the radiobiological response by laser driven particle beams characterised by an ultra high peak dose rate have to be investigated. Therefore, tumour and non-malignant cells were irradiated with pulsed laser accelerated electrons at the JETI facility for the comparison with continuous electrons of a conventional therapy LINAC. Dose response curves were measured for the biological endpoints clonogenic survival and residual DNA double strand breaks. The overall results show no significant differences in radiobiological response for in vitro cell experiments between laser accelerated pulsed and clinical used electron beams. These first systematic in vitro cell response studies with precise dosimetry to laser driven electron beams represent a first step toward the long term aim of the application of laser accelerated particles in radiotherapy.

  4. Radiotherapy physics research in the UK: challenges and proposed solutions.

    PubMed

    Mackay, R I; Burnet, N G; Green, S; Illidge, T M; Staffurth, J N

    2012-10-01

    In 2011, the Clinical and Translational Radiotherapy Research Working Group (CTRad) of the National Cancer Research Institute brought together UK radiotherapy physics leaders for a think tank meeting. Following a format that CTRad had previously and successfully used with clinical oncologists, 23 departments were asked to complete a pre-meeting evaluation of their radiotherapy physics research infrastructure and the strengths, weaknesses, opportunities and threats within their own centre. These departments were brought together with the CTRad Executive Group and research funders to discuss the current state of radiotherapy physics research, perceived barriers and possible solutions. In this Commentary, we summarise the submitted materials, presentations and discussions from the meeting and propose an action plan. It is clear that there are challenges in both funding and staffing of radiotherapy physics research. Programme and project funding streams sometimes struggle to cater for physics-led work, and increased representation on research funding bodies would be valuable. Career paths for academic radiotherapy physicists need to be examined and an academic training route identified within Modernising Scientific Careers; the introduction of formal job plans may allow greater protection of research time, and should be considered. Improved access to research facilities, including research linear accelerators, would enhance research activity and pass on developments to patients more quickly; research infrastructure could be benchmarked against centres in the UK and abroad. UK National Health Service departments wishing to undertake radiotherapy research, with its attendant added value for patients, need to develop a strategy with their partner higher education institution, and collaboration between departments may provide enhanced opportunities for funded research.

  5. Split-course, high-dose palliative pelvic radiotherapy for locally progressive hormone-refractory prostate cancer.

    PubMed

    Gogna, Nirdosh Kumar; Baxi, Siddhartha; Hickey, Brigid; Baumann, Kathryn; Burmeister, Elizabeth; Holt, Tanya

    2012-06-01

    Local progression, in patients with hormone-refractory prostate cancer, often causes significant morbidity. Pelvic radiotherapy (RT) provides effective palliation in this setting, with most published studies supporting the use of high-dose regimens. The aim of the present study was to examine the role of split-course hypofractionated RT used at our institution in treating this group of patients. A total of 34 men with locoregionally progressive hormone-refractory prostate cancer, treated with a split course of pelvic RT (45-60 Gy in 18-24 fractions) between 2000 and 2008 were analyzed. The primary endpoints were the response rate and actuarial locoregional progression-free survival. Secondary endpoints included overall survival, compliance, and acute and late toxicity. The median age was 71 years (range, 53-88). Treatment resulted in an overall initial response rate of 91%, a median locoregional progression-free survival of 43 months, and median overall survival of 28 months. Compliance was excellent and no significant late toxicity was reported. The split course pelvic RT described has an acceptable toxicity profile, is effective, and compares well with other high-dose palliative regimens that have been previously reported. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Accelerated hyperfractionated radiotherapy for cervical cancer: multi-institutional prospective study of forum for nuclear cooperation in Asia among eight Asian countries.

    PubMed

    Ohno, Tatsuya; Nakano, Takashi; Kato, Shingo; Koo, Cho Chul; Chansilpa, Yaowalak; Pattaranutaporn, Pittayapoom; Calaguas, Miriam Joy C; de Los Reyes, Rey H; Zhou, Beibei; Zhou, Juying; Susworo, Raden; Supriana, Nana; Dung, To Anh; Ismail, Fuad; Sato, Sinichiro; Suto, Hisao; Kutsutani-Nakamura, Yuzuru; Tsujii, Hirohiko

    2008-04-01

    To evaluate the toxicity and efficacy of accelerated hyperfractionated radiotherapy (RT) for locally advanced cervical cancer. A multi-institutional prospective single-arm study was conducted among eight Asian countries. Between 1999 and 2002, 120 patients (64 with Stage IIB and 56 with Stage IIIB) with squamous cell carcinoma of the cervix were treated with accelerated hyperfractionated RT. External beam RT consisted of 30 Gy to the whole pelvis, 1.5 Gy/fraction twice daily, followed by 20 Gy of pelvic RT with central shielding at a dose of 2-Gy fractions daily. A small bowel displacement device was used with the patient in the prone position. In addition to central shielding RT, intracavitary brachytherapy was started. Acute and late morbidities were graded according to the Radiation Therapy Oncology Group and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. The median overall treatment time was 35 days. The median follow-up time for surviving patients was 4.7 years. The 5-year pelvic control and overall survival rate for all patients was 84% and 70%, respectively. The 5-year pelvic control and overall survival rate was 78% and 69% for tumors > or = 6 cm in diameter, respectively. No treatment-related death occurred. Grade 3-4 late toxicities of the small intestine, large intestine, and bladder were observed in 1, 1, and 2 patients, respectively. The 5-year actuarial rate of Grade 3-4 late toxicity at any site was 5%. The results of our study have shown that accelerated hyperfractionated RT achieved sufficient pelvic control and survival without increasing severe toxicity. This treatment could be feasible in those Asian countries where chemoradiotherapy is not available.

  7. Dose painting to treat single-lobe prostate cancer with hypofractionated high-dose radiation using targeted external beam radiation: Is it feasible?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Amini, Arya; Westerly, David C.; Waxweiler, Timothy V.

    Targeted focal therapy strategies for treating single-lobe prostate cancer are under investigation. In this planning study, we investigate the feasibility of treating a portion of the prostate to full-dose external beam radiation with reduced dose to the opposite lobe, compared with full-dose radiation delivered to the entire gland using hypofractionated radiation. For 10 consecutive patients with low- to intermediate-risk prostate cancer, 2 hypofractionated, single-arc volumetric-modulated arc therapy (VMAT) plans were designed. The first plan (standard hypofractionation regimen [STD]) included the entire prostate gland, treated to 70 Gy delivered in 28 fractions. The second dose painting plan (DP) encompassed the involvedmore » lobe treated to 70 Gy delivered in 28 fractions, whereas the opposing, uninvolved lobe received 50.4 Gy in 28 fractions. Mean dose to the opposing neurovascular bundle (NVB) was considerably lower for DP vs STD, with a mean dose of 53.9 vs 72.3 Gy (p < 0.001). Mean penile bulb dose was 18.6 Gy for DP vs 19.2 Gy for STD (p = 0.880). Mean rectal dose was 21.0 Gy for DP vs 22.8 Gy for STD (p = 0.356). Rectum V{sub 70} (the volume receiving ≥70 Gy) was 2.01% for DP vs 2.74% for STD (p = 0.328). Bladder V{sub 70} was 1.69% for DP vs 2.78% for STD (p = 0.232). Planning target volume (PTV) maximum dose points were 76.5 and 76.3 Gy for DP and STD, respectively (p = 0.760). This study demonstrates the feasibility of using VMAT for partial-lobe prostate radiation in patients with prostate cancer involving 1 lobe. Partial-lobe prostate plans appeared to spare adjacent critical structures including the opposite NVB.« less

  8. Intelligent ePR system for evidence-based research in radiotherapy: proton therapy for prostate cancer.

    PubMed

    Le, Anh H; Liu, Brent; Schulte, Reinhard; Huang, H K

    2011-11-01

    Proton therapy (PT) utilizes high energy particle proton beam to kill cancer cells at the target region for target cancer therapy. Due to the physical properties of the proton beam, PT delivers dose with higher precision and no exit dose compared to conventional radiotherapy. In PT, patient data are distributed among multiple systems, a hindrance to research on efficacy and effectiveness. A data mining method and a treatment plan navigator utilizing the infrastructure and data repository of a PT electronic patient record (ePR) was developed to minimize radiation toxicity and improve outcomes in prostate cancer treatment. MATERIALS/METHOD(S): The workflow of a proton therapy treatment in a radiation oncology department was reviewed, and a clinical data model and data flow were designed. A prototype PT ePR system with DICOM compliance was developed to manage prostate cancer patient images, treatment plans, and related clinical data. The ePR system consists of four main components: (1) Data Gateway; (2) ePR Server; (3) Decision Support Tools; and (4) Visualization and Display Tools. Decision support and visualization tools are currently developed based on DICOM images, DICOM-RT and DICOM-RT-ION objects data from prostate cancer patients treated with hypofractionation protocol proton therapy were used for evaluating ePR system effectiveness. Each patient data set includes a set of computed tomography (CT) DICOM images and four DICOM-RT and RT-ION objects. In addition, clinical outcomes data collected from PT cases were included to establish a knowledge base for outcomes analysis. A data mining search engine and an intelligent treatment plan navigator (ITPN) were developed and integrated with the ePR system. Evaluation was based on a data set of 39 PT patients and a hypothetical patient. The ePR system was able to facilitate the proton therapy workflow. The PT ePR system was feasible for prostate cancer patient treated with hypofractionation protocol in proton therapy

  9. Magnetic resonance imaging for precise radiotherapy of small laboratory animals.

    PubMed

    Frenzel, Thorsten; Kaul, Michael Gerhard; Ernst, Thomas Michael; Salamon, Johannes; Jäckel, Maria; Schumacher, Udo; Krüll, Andreas

    2017-03-01

    Radiotherapy of small laboratory animals (SLA) is often not as precisely applied as in humans. Here we describe the use of a dedicated SLA magnetic resonance imaging (MRI) scanner for precise tumor volumetry, radiotherapy treatment planning, and diagnostic imaging in order to make the experiments more accurate. Different human cancer cells were injected at the lower trunk of pfp/rag2 and SCID mice to allow for local tumor growth. Data from cross sectional MRI scans were transferred to a clinical treatment planning system (TPS) for humans. Manual palpation of the tumor size was compared with calculated tumor size of the TPS and with tumor weight at necropsy. As a feasibility study MRI based treatment plans were calculated for a clinical 6MV linear accelerator using a micro multileaf collimator (μMLC). In addition, diagnostic MRI scans were used to investigate animals which did clinical poorly during the study. MRI is superior in precise tumor volume definition whereas manual palpation underestimates their size. Cross sectional MRI allow for treatment planning so that conformal irradiation of mice with a clinical linear accelerator using a μMLC is in principle feasible. Several internal pathologies were detected during the experiment using the dedicated scanner. MRI is a key technology for precise radiotherapy of SLA. The scanning protocols provided are suited for tumor volumetry, treatment planning, and diagnostic imaging. Copyright © 2016. Published by Elsevier GmbH.

  10. Acute Toxicity Profile and Compliance to Accelerated Radiotherapy Plus Carbogen and Nicotinamide for Clinical Stage T2-4 Laryngeal Cancer: Results of a Phase III Randomized Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Janssens, Geert O., E-mail: g.janssens@rther.umcn.nl; Terhaard, Chris H.; Doornaert, Patricia A.

    2012-02-01

    Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with cT2-4 squamous cell laryngeal cancer were randomized to AR (n = 174) and ARCON (n = 171). Acute toxicity was scored weekly until Week 8 and every 2-4 weeks thereafter. Compliance to carbogen and nicotinamide was reported. Results: Between both treatment arms (AR vs. ARCON) no statistically significant difference was observed for incidence of acute skin reactions (moistmore » desquamation: 56% vs. 58%, p = 0.80), acute mucosal reactions (confluent mucositis: 79% vs. 85%, p = 0.14), and symptoms related to acute mucositis (severe pain on swallowing: 53% vs. 58%, p = 0.37; nasogastric tube feeding: 28% vs. 28%, p = 0.98; narcotic medicines required: 58% vs. 58%, p = 0.97). There was a statistically significant difference in median duration of confluent mucositis in favor of AR (2.0 vs 3.0 weeks, p = 0.01). There was full compliance with carbogen breathing and nicotinamide in 86% and 80% of the patients, with discontinuation in 6% and 12%, respectively. Adjustment of antiemesis prophylaxis was needed in 42% of patients. Conclusion: With the exception of a slight increase in median duration of acute confluent mucositis, the present data reveal a similar acute toxicity profile between both regimens and a good compliance with ARCON for clinical stage T2-4 laryngeal cancers. Treatment outcome and late morbidity will determine the real therapeutic benefit.« less

  11. The effectiveness of a pneumatic compression belt in reducing respiratory motion of abdominal tumors in patients undergoing stereotactic body radiotherapy.

    PubMed

    Lovelock, D Michael; Zatcky, Joan; Goodman, Karyn; Yamada, Yoshiya

    2014-06-01

    Abdominal compression using a pneumatic abdominal compression belt developed in-house has been used to reduce respiratory motion of patients undergoing hypo-fractionated or single fraction stereotactic radio-ablative therapy for abdominal cancers. The clinical objective of belt usage was to reduce the cranial-caudal (CC) respiratory motion of the tumor to 5 mm or less during both CT simulation and treatment. A retrospective analysis was done to determine the effectiveness of the device and associated clinical procedures to reduce the CC respiratory motion of the tumor. 42 patients treated for tumors in the liver (30), adrenal glands (6), pancreas (3) and lymph nodes (3) using high dose hypofractionated radiotherapy between 2004 and the present were eligible for analysis. All patients had 2-3 radiopaque fiducial markers implanted near the tumor prior to simulation, or had clips from prior surgery. Integral to the belt is an inflatable air bladder that is positioned over the abdomen. The pneumatic pressure was set to a level in consultation with the patient. The CC motion was measured fluoroscopically with and without pneumatic pressure. Pneumatic pressure was used at all treatments to reduce to CC motion to that achieved at simulation. The mean CC motion with the belt in place, but no additional air pressure was 11.4 mm with a range of 5-20 mm. With the pressure applied, the mean CC motion was reduced to 4.4 mm with a range of 1-8 mm (P-value < 0.001). The clinical objective of reducing the CC motion of the tumor to a maximum excursion of 5 mm or less was achieved in 93% of cases. The use of a pneumatic compression belt and associated clinical procedures was found to result in a significant and frequently substantial reduction in the CC motion of the tumor.

  12. Permanent-magnet energy spectrometer for electron beams from radiotherapy accelerators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McLaughlin, David J.; Shikhaliev, Polad M.; Matthews, Kenneth L.

    2015-09-15

    Purpose: The purpose of this work was to adapt a lightweight, permanent magnet electron energy spectrometer for the measurement of energy spectra of therapeutic electron beams. Methods: An irradiation geometry and measurement technique were developed for an approximately 0.54-T, permanent dipole magnet spectrometer to produce suitable latent images on computed radiography (CR) phosphor strips. Dual-pinhole electron collimators created a 0.318-cm diameter, approximately parallel beam incident on the spectrometer and an appropriate dose rate at the image plane (CR strip location). X-ray background in the latent image, reduced by a 7.62-cm thick lead block between the pinhole collimators, was removed usingmore » a fitting technique. Theoretical energy-dependent detector response functions (DRFs) were used in an iterative technique to transform CR strip net mean dose profiles into energy spectra on central axis at the entrance to the spectrometer. These spectra were transformed to spectra at 95-cm source to collimator distance (SCD) by correcting for the energy dependence of electron scatter. The spectrometer was calibrated by comparing peak mean positions in the net mean dose profiles, initially to peak mean energies determined from the practical range of central-axis percent depth-dose (%DD) curves, and then to peak mean energies that accounted for how the collimation modified the energy spectra (recalibration). The utility of the spectrometer was demonstrated by measuring the energy spectra for the seven electron beams (7–20 MeV) of an Elekta Infinity radiotherapy accelerator. Results: Plots of DRF illustrated their dependence on energy and position in the imaging plane. Approximately 15 iterations solved for the energy spectra at the spectrometer entrance from the measured net mean dose profiles. Transforming those spectra into ones at 95-cm SCD increased the low energy tail of the spectra, while correspondingly decreasing the peaks and shifting them to

  13. Permanent-magnet energy spectrometer for electron beams from radiotherapy accelerators.

    PubMed

    McLaughlin, David J; Hogstrom, Kenneth R; Carver, Robert L; Gibbons, John P; Shikhaliev, Polad M; Matthews, Kenneth L; Clarke, Taylor; Henderson, Alexander; Liang, Edison P

    2015-09-01

    The purpose of this work was to adapt a lightweight, permanent magnet electron energy spectrometer for the measurement of energy spectra of therapeutic electron beams. An irradiation geometry and measurement technique were developed for an approximately 0.54-T, permanent dipole magnet spectrometer to produce suitable latent images on computed radiography (CR) phosphor strips. Dual-pinhole electron collimators created a 0.318-cm diameter, approximately parallel beam incident on the spectrometer and an appropriate dose rate at the image plane (CR strip location). X-ray background in the latent image, reduced by a 7.62-cm thick lead block between the pinhole collimators, was removed using a fitting technique. Theoretical energy-dependent detector response functions (DRFs) were used in an iterative technique to transform CR strip net mean dose profiles into energy spectra on central axis at the entrance to the spectrometer. These spectra were transformed to spectra at 95-cm source to collimator distance (SCD) by correcting for the energy dependence of electron scatter. The spectrometer was calibrated by comparing peak mean positions in the net mean dose profiles, initially to peak mean energies determined from the practical range of central-axis percent depth-dose (%DD) curves, and then to peak mean energies that accounted for how the collimation modified the energy spectra (recalibration). The utility of the spectrometer was demonstrated by measuring the energy spectra for the seven electron beams (7-20 MeV) of an Elekta Infinity radiotherapy accelerator. Plots of DRF illustrated their dependence on energy and position in the imaging plane. Approximately 15 iterations solved for the energy spectra at the spectrometer entrance from the measured net mean dose profiles. Transforming those spectra into ones at 95-cm SCD increased the low energy tail of the spectra, while correspondingly decreasing the peaks and shifting them to slightly lower energies. Energy calibration

  14. Significance of tumor volume related to peritumoral edema in intracranial meningioma treated with extreme hypofractionated stereotactic radiation therapy in three to five fractions.

    PubMed

    Morimoto, Masahiro; Yoshioka, Yasuo; Shiomi, Hiroya; Isohashi, Fumiaki; Konishi, Koji; Kotsuma, Tadayuki; Fukuda, Shoichi; Kagawa, Naoki; Kinoshita, Manabu; Hashimoto, Naoya; Yoshimine, Toshiki; Koizumi, Masahiko

    2011-05-01

    To investigate the treatment results of intracranial meningiomas treated with hypofractionated stereotactic radiation therapy in three to five fractions. Thirty-one patients (32 lesions) with intracranial meningioma were treated with hypofractionated stereotactic radiation therapy in three to five fractions using CyberKnife. Fifteen lesions were diagnosed as Grade I (World Health Organization classification) by surgical resection and 17 lesions were diagnosed as meningioma based on radiological findings. The median follow-up time was 48 months. The median planning target volume was 6.3 cm(3) (range, 1.4-27.1), and the prescribed dose (D90≤) ranged from 21 to 36 Gy (median, 27.8) administrated in three to five fractions. Five-year overall and progression-free survival rate of all 31 patients with intracranial meningioma was 86 and 83%, respectively. Five-year progression-free rate of all 32 lesions was 87%. Six of the 31 patients (19%) developed marked peritumoral edema, three of whom were asymptomatic and three symptomatic, the latter with late adverse effects of more than or equal to Grade 3. The mean planning target volume of the six lesions with marked peritumoral edema was 15.6 cm(3), and for the remaining 26 lesions without marked peritumoral edema was 7.1 cm(3) (P = 0.004). The threshold diameter of 2.56 cm for meningioma was calculated from the planning target volume (11 cm(3)) and was used as marker of developing peritumoral edema (P = 0.003). Tumor volume is a significant indicative factor for peritumoral edema in intracranial meningioma treated with hypofractionated stereotactic radiation therapy in three to five factions.

  15. HI-CHART: a phase I/II study on the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer.

    PubMed

    De Ruysscher, Dirk; Wanders, Rinus; van Haren, Erik; Hochstenbag, Monique; Geraedts, Wiel; Pitz, Cordula; Simons, Jean; Boersma, Liesbeth; Verschueren, Tom; Minken, Andre; Bentzen, Søren M; Lambin, Philippe

    2008-05-01

    To determine the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer (NSCLC). In a prospective, Phase I/II study, according to the risk for radiation pneumonitis, three risk groups were defined: V(20) <25%, V(20) 25-37%, and V(20) >37%. The dose was administered in three steps from 61.2 Gy/34 fractions/23 days to 64.8 Gy/36 fractions/24 days to 68.40 Gy/38 fractions/25 days (1.8 Gy b.i.d. with 8-h interval), using a three-dimensional conformal technique. Only the mediastinal lymph node areas that were positive on the pretreatment (18)F-deoxy-D-glucose positron emission tomography scan were included in the target volume. The primary endpoint was toxicity. A total of 48 Stage I-IIIB patients were included. In all risk groups, 68.40 Gy/38 fractions/25 days could be administered. Maximal toxicity according to the risk groups was as follows: V(20) <25% (n = 35): 1 Grade 4 (G4) lung and 1 G3 reversible esophageal toxicity; V(20) 35-37% (n = 12): 1 G5 lung and 1 G3 reversible esophageal toxicity. For the whole group, local tumor recurrence occurred in 25% (95% confidence interval 14%-40%) of the patients, with 1 of 48 (2.1%; upper one-sided 95% confidence limit 9.5%) having an isolated nodal recurrence. The median actuarial overall survival was 20 months, with a 2-year survival rate of 36%. High-dose continuous hyperfractionated accelerated radiotherapy up to a dose of 68.40 Gy/38 fractions/25 days (a biologic equivalent of approximately 80 Gy when delivered in conventional fractionation) in patients with inoperable NSCLC and a V(20) up to 37% is feasible.

  16. Hyperfractionated accelerated radiotherapy with concomitant integrated boost of 70-75 Gy in 5 weeks for advanced head and neck cancer. A phase I dose escalation study.

    PubMed

    Cvek, J; Kubes, J; Skacelikova, E; Otahal, B; Kominek, P; Halamka, M; Feltl, D

    2012-08-01

    The present study was performed to evaluate the feasibility of a new, 5-week regimen of 70-75 Gy hyperfractionated accelerated radiotherapy with concomitant integrated boost (HARTCIB) for locally advanced, inoperable head and neck cancer. A total of 39 patients with very advanced, stage IV nonmetastatic head and neck squamous cell carcinoma (median gross tumor volume 72 ml) were included in this phase I dose escalation study. A total of 50 fractions intensity-modulated radiotherapy (IMRT) were administered twice daily over 5 weeks. Prescribed total dose/dose per fraction for planning target volume (PTV(tumor)) were 70 Gy in 1.4 Gy fractions, 72.5 Gy in 1.45 Gy fractions, and 75 Gy in 1.5 Gy fractions for 10, 13, and 16 patients, respectively. Uninvolved lymphatic nodes (PTV(uninvolved)) were irradiated with 55 Gy in 1.1 Gy fractions using the concomitant integrated boost. Acute toxicity was evaluated according to the RTOG/EORTC scale; the incidence of grade 3 mucositis was 51% in the oral cavity/pharynx and 0% in skin and the recovery time was ≤ 9 weeks for all patients. Late toxicity was evaluated in patients in complete remission according to the RTOG/EORTC scale. No grade 3/4 late toxicity was observed. The 1-year locoregional progression-free survival was 50% and overall survival was 55%. HARTCIB (75 Gy in 5 weeks) is feasible for patients deemed unsuitable for chemoradiation. Acute toxicity was lower than predicted from radiobiological models; duration of dysphagia and confluent mucositis were particularly short. Better conformity of radiotherapy allows the use of more intensive altered fractionation schedules compared with older studies. These results suggest that further dose escalation might be possible when highly conformal techniques (e.g., stereotactic radiotherapy) are used.

  17. Radiotherapy physics research in the UK: challenges and proposed solutions

    PubMed Central

    Mackay, R I; Burnet, N G; Green, S; Illidge, T M; Staffurth, J N

    2012-01-01

    In 2011, the Clinical and Translational Radiotherapy Research Working Group (CTRad) of the National Cancer Research Institute brought together UK radiotherapy physics leaders for a think tank meeting. Following a format that CTRad had previously and successfully used with clinical oncologists, 23 departments were asked to complete a pre-meeting evaluation of their radiotherapy physics research infrastructure and the strengths, weaknesses, opportunities and threats within their own centre. These departments were brought together with the CTRad Executive Group and research funders to discuss the current state of radiotherapy physics research, perceived barriers and possible solutions. In this Commentary, we summarise the submitted materials, presentations and discussions from the meeting and propose an action plan. It is clear that there are challenges in both funding and staffing of radiotherapy physics research. Programme and project funding streams sometimes struggle to cater for physics-led work, and increased representation on research funding bodies would be valuable. Career paths for academic radiotherapy physicists need to be examined and an academic training route identified within Modernising Scientific Careers; the introduction of formal job plans may allow greater protection of research time, and should be considered. Improved access to research facilities, including research linear accelerators, would enhance research activity and pass on developments to patients more quickly; research infrastructure could be benchmarked against centres in the UK and abroad. UK National Health Service departments wishing to undertake radiotherapy research, with its attendant added value for patients, need to develop a strategy with their partner higher education institution, and collaboration between departments may provide enhanced opportunities for funded research. PMID:22972972

  18. Recent progress of a superconducting rotating-gantry for carbon-ion radiotherapy

    NASA Astrophysics Data System (ADS)

    Iwata, Y.; Fujimoto, T.; Matsuba, S.; Fujita, T.; Sato, S.; Furukawa, T.; Hara, Y.; Mizushima, K.; Saraya, Y.; Tansho, R.; Saotome, N.; Shirai, T.; Noda, K.

    2017-09-01

    A superconducting rotating-gantry for carbon-ion radiotherapy was developed. This isocentric rotating gantry can transport carbon ions having the maximum kinetic energy of E = 430 MeV/u to an isocenter with irradiation angles of over ±180°, and is further capable of performing three-dimensional raster-scanning irradiation. By using combined-function superconducting magnets, we could design a compact rotating gantry for carbon-ion radiotherapy. Construction of the gantry structure began since early 2014, and the installation of the entire gantry system to the Heavy Ion Medical Accelerator in Chiba (HIMAC) complex was completed by the end of September, 2015. Beam tuning subsequently began since October, 2015, and carbon ions, as accelerated by the HIMAC upper synchrotron, having kinetic energies of between E = 430-48 MeV/u were successfully transported with the rotating gantry to the isocenter. The size and shape of the beam spots at the isocenter is being tuned over various combinations of the beam energies and the gantry angle. We will present the recent progress as well as the current status of the superconducting rotating-gantry.

  19. Phase 2 Trial of Hypofractionated High-Dose Intensity Modulated Radiation Therapy With Concurrent and Adjuvant Temozolomide for Newly Diagnosed Glioblastoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Iuchi, Toshihiko, E-mail: tiuchi@chiba-c.jp; Hatano, Kazuo; Kodama, Takashi

    Purpose/Objectives: To assess the effect and toxicity of hypofractionated high-dose intensity modulated radiation therapy (IMRT) with concurrent and adjuvant temozolomide (TMZ) in 46 patients with newly diagnosed glioblastoma multiforme (GBM). Methods and Materials: All patients underwent postsurgical hypofractionated high-dose IMRT. Three layered planning target volumes (PTVs) were contoured. PTV1 was the surgical cavity and residual tumor on T1-weighted magnetic resonance images with 5-mm margins, PTV2 was the area with 15-mm margins surrounding the PTV1, and PTV3 was the high-intensity area on fluid-attenuated inversion recovery images. Irradiation was performed in 8 fractions at total doses of 68, 40, and 32 Gy formore » PTV1, PTV2, and PTV3, respectively. Concurrent TMZ was given at 75 mg/m{sup 2}/day for 42 consecutive days. Adjuvant TMZ was given at 150 to 200 mg/m{sup 2}/day for 5 days every 28 days. Overall and progression-free survivals were evaluated. Results: No acute IMRT-related toxicity was observed. The dominant posttreatment failure pattern was dissemination. During a median follow-up time of 16.3 months (range, 4.3-80.8 months) for all patients and 23.7 months (range, 12.4-80.8 months) for living patients, the median overall survival was 20.0 months after treatment. Radiation necrosis was diagnosed in 20 patients and was observed not only in the high-dose field but also in the subventricular zone (SVZ). Necrosis in the SVZ was significantly correlated with prolonged survival (hazard ratio, 4.08; P=.007) but caused deterioration in the performance status of long-term survivors. Conclusions: Hypofractionated high-dose IMRT with concurrent and adjuvant TMZ altered the dominant failure pattern from localized to disseminated and prolonged the survival of patients with GBM. Necrosis in the SVZ was associated with better patient survival, but the benefit of radiation to this area remains controversial.« less

  20. Accelerated Hyperfractionated Radiotherapy for Cervical Cancer: Multi-Institutional Prospective Study of Forum for Nuclear Cooperation in Asia Among Eight Asian Countries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ohno, Tatsuya; Nakano, Takashi; Kato, Shingo

    2008-04-01

    Purpose: To evaluate the toxicity and efficacy of accelerated hyperfractionated radiotherapy (RT) for locally advanced cervical cancer. Methods and Materials: A multi-institutional prospective single-arm study was conducted among eight Asian countries. Between 1999 and 2002, 120 patients (64 with Stage IIB and 56 with Stage IIIB) with squamous cell carcinoma of the cervix were treated with accelerated hyperfractionated RT. External beam RT consisted of 30 Gy to the whole pelvis, 1.5 Gy/fraction twice daily, followed by 20 Gy of pelvic RT with central shielding at a dose of 2-Gy fractions daily. A small bowel displacement device was used with themore » patient in the prone position. In addition to central shielding RT, intracavitary brachytherapy was started. Acute and late morbidities were graded according to the Radiation Therapy Oncology Group and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Results: The median overall treatment time was 35 days. The median follow-up time for surviving patients was 4.7 years. The 5-year pelvic control and overall survival rate for all patients was 84% and 70%, respectively. The 5-year pelvic control and overall survival rate was 78% and 69% for tumors {>=}6 cm in diameter, respectively. No treatment-related death occurred. Grade 3-4 late toxicities of the small intestine, large intestine, and bladder were observed in 1, 1, and 2 patients, respectively. The 5-year actuarial rate of Grade 3-4 late toxicity at any site was 5%. Conclusion: The results of our study have shown that accelerated hyperfractionated RT achieved sufficient pelvic control and survival without increasing severe toxicity. This treatment could be feasible in those Asian countries where chemoradiotherapy is not available.« less

  1. The Nano-X Linear Accelerator: A Compact and Economical Cancer Radiotherapy System Incorporating Patient Rotation.

    PubMed

    Eslick, Enid M; Keall, Paul J

    2015-10-01

    Rapid technological improvements in radiotherapy delivery results in improved outcomes to patients, yet current commercial systems with these technologies on board are costly. The aim of this study was to develop a state-of-the-art cancer radiotherapy system that is economical and space efficient fitting with current world demands. The Nano-X system is a compact design that is light weight combining a patient rotation system with a vertical 6 MV fixed beam. In this paper, we present the Nano-X system design configuration, an estimate of the system dimensions and its potential impact on shielding cost reductions. We provide an assessment of implementing such a radiotherapy system clinically, its advantages and disadvantages compared to a compact conventional gantry rotating linac. The Nano-X system has several differentiating features from current radiotherapy systems, it is [1] compact and therefore can fit into small vaults, [2] light weight, and [3] engineering efficient, i.e., it rotates a relatively light component and the main treatment delivery components are not under rotation (e.g., DMLCs). All these features can have an impact on reducing the costs of the system. In terms of shielding requirements, leakage radiation was found to be the dominant contributor to the Nano-X vault and as such no primary shielding was necessary. For a low leakage design, the Nano-X vault footprint and concrete volume required is 17 m2 and 35 m3 respectively, compared to 54 m2 and 102 m3 for a conventional compact linac vault, resulting in decreased costs in shielding. Key issues to be investigated in future work are the possible patient comfort concerns associated with the patient rotation system, as well as the magnitude of deformation and subsequent adaptation requirements. © The Author(s) 2014.

  2. A versatile program for the calculation of linear accelerator room shielding.

    PubMed

    Hassan, Zeinab El-Taher; Farag, Nehad M; Elshemey, Wael M

    2018-03-22

    This work aims at designing a computer program to calculate the necessary amount of shielding for a given or proposed linear accelerator room design in radiotherapy. The program (Shield Calculation in Radiotherapy, SCR) has been developed using Microsoft Visual Basic. It applies the treatment room shielding calculations of NCRP report no. 151 to calculate proper shielding thicknesses for a given linear accelerator treatment room design. The program is composed of six main user-friendly interfaces. The first enables the user to upload their choice of treatment room design and to measure the distances required for shielding calculations. The second interface enables the user to calculate the primary barrier thickness in case of three-dimensional conventional radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT) and total body irradiation (TBI). The third interface calculates the required secondary barrier thickness due to both scattered and leakage radiation. The fourth and fifth interfaces provide a means to calculate the photon dose equivalent for low and high energy radiation, respectively, in door and maze areas. The sixth interface enables the user to calculate the skyshine radiation for photons and neutrons. The SCR program has been successfully validated, precisely reproducing all of the calculated examples presented in NCRP report no. 151 in a simple and fast manner. Moreover, it easily performed the same calculations for a test design that was also calculated manually, and produced the same results. The program includes a new and important feature that is the ability to calculate required treatment room thickness in case of IMRT and TBI. It is characterised by simplicity, precision, data saving, printing and retrieval, in addition to providing a means for uploading and testing any proposed treatment room shielding design. The SCR program provides comprehensive, simple, fast and accurate room shielding calculations in radiotherapy.

  3. Analysis of errors detected in external beam audit dosimetry program at Mexican radiotherapy centers

    NASA Astrophysics Data System (ADS)

    Álvarez-Romero, José T.; Tovar-Muñoz, Víctor M.

    2012-10-01

    Presented and analyzed are the causes of deviation observed in the pilot postal dosimetry audit program to verify the absorbed dose to water Dw in external beams of teletherapy 60Co and/or linear accelerators in Mexican radiotherapy centers, during the years 2007-2011.

  4. Technologies for delivery of proton and ion beams for radiotherapy

    NASA Astrophysics Data System (ADS)

    Owen, Hywel; Holder, David; Alonso, Jose; Mackay, Ranald

    2014-05-01

    Recent developments for the delivery of proton and ion beam therapy have been significant, and a number of technological solutions now exist for the creation and utilisation of these particles for the treatment of cancer. In this paper we review the historical development of particle accelerators used for external beam radiotherapy and discuss the more recent progress towards more capable and cost-effective sources of particles.

  5. Verification of respiratory-gated radiotherapy with new real-time tumour-tracking radiotherapy system using cine EPID images and a log file.

    PubMed

    Shiinoki, Takehiro; Hanazawa, Hideki; Yuasa, Yuki; Fujimoto, Koya; Uehara, Takuya; Shibuya, Keiko

    2017-02-21

    A combined system comprising the TrueBeam linear accelerator and a new real-time tumour-tracking radiotherapy system, SyncTraX, was installed at our institution. The objectives of this study are to develop a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine electronic portal image device (EPID) images and a log file and to verify this treatment in clinical cases. Respiratory-gated radiotherapy was performed using TrueBeam and the SyncTraX system. Cine EPID images and a log file were acquired for a phantom and three patients during the course of the treatment. Digitally reconstructed radiographs (DRRs) were created for each treatment beam using a planning CT set. The cine EPID images, log file, and DRRs were analysed using a developed software. For the phantom case, the accuracy of the proposed method was evaluated to verify the respiratory-gated radiotherapy. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker used as an internal surrogate were calculated to evaluate the gating accuracy and set-up uncertainty in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions. The proposed method achieved high accuracy for the phantom verification. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker were  ⩽3 mm and  ±3 mm in the SI, AP, and LR directions. We proposed a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine EPID images and a log file and showed that this treatment is performed with high accuracy in clinical cases.

  6. Utilization of hypofractionated whole-breast radiation therapy in patients receiving chemotherapy: a National Cancer Database analysis.

    PubMed

    Diwanji, Tejan P; Molitoris, Jason K; Chhabra, Arpit M; Snider, James W; Bentzen, Soren M; Tkaczuk, Katherine H; Rosenblatt, Paula Y; Kesmodel, Susan B; Bellavance, Emily C; Cohen, Randi J; Cheston, Sally B; Nichols, Elizabeth M; Feigenberg, Steven J

    2017-09-01

    Results from four major hypofractionated whole-breast radiotherapy (HF-WBRT) trials have demonstrated equivalence in select patients with early-stage breast cancer when compared with conventionally fractionated WBRT (CF-WBRT). Because relatively little data were available on patients receiving neoadjuvant or adjuvant chemotherapy, consensus guidelines published in 2011 did not endorse the use of HF-WBRT in this population. Our goal is to evaluate trends in utilization of HF-WBRT in patients receiving chemotherapy. We retrospectively analyzed data from 2004 to 2013 in the National Cancer DataBase on breast cancer patients treated with HF-WBRT who met the clinical criteria proposed by consensus guidelines (i.e., age >0 years, T1-2N0, and breast-conserving surgery), regardless of receipt of chemotherapy. We employed logistic regression to delineate and compare clinical and demographic factors associated with utilization of HF-WBRT and CF-WBRT. A total of 56,836 women were treated with chemotherapy and WBRT (without regional nodal irradiation) from 2004 to 2013; 9.0% (n = 5093) were treated with HF-WBRT. Utilization of HF-WBRT increased from 4.6% in 2004 to 18.2% in 2013 (odds ratio [OR] 1.21/year; P < 0.001). Among patients receiving chemotherapy, factors most dramatically associated with increased odds of receiving HF-WBRT on multivariate analysis were academic facilities (OR 2.07; P < 0.001), age >80 (OR 2.58; P < 0.001), west region (OR 1.91; P < 0.001), and distance >50 miles from cancer reporting facility (OR 1.43; P < 0.001). Factors associated with decreased odds of receiving HF-WBRT included white race, income <$48,000, lack of private insurance, T2 versus T1, and higher grade (all P < 0.02). Despite the absence of consensus guideline recommendations, the use of HF-WBRT in patients receiving chemotherapy has increased fourfold (absolute = 13.6%) over the last decade. Increased utilization of HF-WBRT should result in institutional reports

  7. Radiation techniques used in patients with breast cancer: Results of a survey in Spain

    PubMed Central

    Algara, Manuel; Arenas, Meritxell; De las Peñas Eloisa Bayo, Dolores; Muñoz, Julia; Carceller, José Antonio; Salinas, Juan; Moreno, Ferran; Martínez, Francisco; González, Ezequiel; Montero, Ángel

    2012-01-01

    Aim To evaluate the resources and techniques used in the irradiation of patients with breast cancer after lumpectomy or mastectomy and the status of implementation of new techniques and therapeutic schedules in our country. Background The demand for cancer care has increased among the Spanish population, as long as cancer treatment innovations have proliferated. Radiation therapy in breast cancer has evolved exponentially in recent years with the implementation of three-dimensional conformal radiotherapy, intensity modulated radiotherapy, image guided radiotherapy and hypofractionation. Material and Methods An original survey questionnaire was sent to institutions participating in the SEOR-Mama group (GEORM). In total, the standards of practice in 969 patients with breast cancer after surgery were evaluated. Results The response rate was 70% (28/40 centers). In 98.5% of cases 3D conformal treatment was used. All the institutions employed CT-based planning treatment. Boost was performed in 56.4% of patients: electrons in 59.8%, photons in 23.7% and HDR brachytherapy in 8.8%. Fractionation was standard in 93.1% of patients. Supine position was the most frequent. Only 3 centers used prone position. The common organs of risk delimited were: homolateral lung (80.8%) and heart (80.8%). In 84% histograms were used. An 80.8% of the centers used isocentric technique. In 62.5% asymmetric fields were employed. CTV was delimited in 46.2%, PTV in 65% and both in 38.5%. A 65% of the centers checked with portal films. IMRT and hypofractionation were used in 1% and in 5.5% respectively. Conclusion In most of centers, 3D conformal treatment and CT-based planning treatment were used. IMRT and hypofractionation are currently poorly implemented in Spain. PMID:24377012

  8. Cost-effectiveness analysis of intensity-modulated radiation therapy with normal and hypofractionated schemes for the treatment of localised prostate cancer.

    PubMed

    Zemplényi, A T; Kaló, Z; Kovács, G; Farkas, R; Beöthe, T; Bányai, D; Sebestyén, Z; Endrei, D; Boncz, I; Mangel, L

    2018-01-01

    The aim of our analysis was to compare the cost-effectiveness of high-dose intensity-modulated radiation therapy (IMRT) and hypofractionated intensity-modulated radiation therapy (HF-IMRT) versus conventional dose three-dimensional radiation therapy (3DCRT) for the treatment of localised prostate cancer. A Markov model was constructed to calculate the incremental quality-adjusted life years and costs. Transition probabilities, adverse events and utilities were derived from relevant systematic reviews. Microcosting in a large university hospital was applied to calculate cost vectors. The expected mean lifetime cost of patients undergoing 3DCRT, IMRT and HF-IMRT were 7,160 euros, 6,831 euros and 6,019 euros respectively. The expected quality-adjusted life years (QALYs) were 5.753 for 3DCRT, 5.956 for IMRT and 5.957 for HF-IMRT. Compared to 3DCRT, both IMRT and HF-IMRT resulted in more health gains at a lower cost. It can be concluded that high-dose IMRT is not only cost-effective compared to the conventional dose 3DCRT but, when used with a hypofractionation scheme, it has great cost-saving potential for the public payer and may improve access to radiation therapy for patients. © 2016 John Wiley & Sons Ltd.

  9. TU-A-BRD-01: Outcomes of Hypofractionated Treatments - Initial Results of the WGSBRT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, X; Lee, P; Ohri, N

    2014-06-15

    Stereotactic Body Radiation Therapy (SBRT) has emerged in recent decades as a treatment paradigm that is becoming increasingly important in clinical practice. Clinical outcomes data are rapidly accumulating. Although published relations between outcomes and dose distributions are still sparse, the field has progressed to the point where evidence-based normal tissue dose-volume constraints, prescription strategies, and Tumor Control Probability (TCP) and Normal Tissue Complication Probability (NTCP) models can be developed. The Working Group on SBRT (WGSBRT), under the Biological Effects Subcommittee of AAPM, is a group of physicists and physicians working in the area of SBRT. It is currently performing criticalmore » literature reviews to extract and synthesize usable data and to develop guidelines and models to aid with safe and effective treatment. The group is investigating clinically relevant findings from SBRT in six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session of AAPM 2014, interim results are presented on TCP for lung and liver, NTCP for thoracic organs, and radiobiological foundations:• Lung TCP: Detailed modeling of TCP data from 118 published studies on early stage lung SBRT investigates dose response and hypothesized mechanisms to explain the improved outcomes of SBRT. This is presented from the perspective of a physicist, a physician, and a radiobiologist.• Liver TCP: For primary and metastatic liver tumors, individual patient data were extracted from published reports to examine the effects of biologically effective dose on local control.• Thoracic NTCP: Clinically significant SBRT toxicity of lung, rib / chest wall and other structures are evaluated and compared among published clinical data, in terms of risk, risk factors, and safe practice.• Improving the clinical utility of published toxicity reports from SBRT and Hypofractionated treatments. What do we want, and how do we get it

  10. [Role of radiotherapy in stage I testicular seminomas: about 25 cases].

    PubMed

    Aissa, Abdellah; Marnouche, Elamin; Elkacemi, Hanan; Kebdani, Tayeb; Benjaafar, Noureddine

    2016-01-01

    We conducted a retrospective, descriptive study of 25 stage I testicular seminomas to clarify the role of radiotherapy in the management of this disease. Between January 2001 and December 2009, 25 patients with stage I testicular seminoma were treated in the Radiotherapy Department at the National Institute of Oncology in Rabat. Primary orchidectomy was performed via the inguinal route. Initial staging was based on total beta-hCG dosage, alpha-fetoprotein dosage and exploration of superior diaphragmatic and sub-diaphragmatic lymph nodes using tomodensitometry. Adjuvant radiotherapy was delivered using linear accelerator. The median age was 33 years (18-52 years). Testicular tumor involved the right side in 16 patients and the left side in 9 patients. Radiotherapy was delivered to lombo-aortic lymph nodes in 18 patients, lombo-aortic and ipsilateral iliac lymph nodes in 7 patients, using 2 anterior-posterior beams, with delivery of 20-25 Gy in 10-14 fractions. Immediate tolerance was excellent. The average monitoring period was 73 months. Twenty three patients are currently alive in complete remission. One patient developed a pulmonary relapse 22 months after the end of the radiotherapy. One patient was lost to follow-up. Long-term toxicity, especially gastrointestinal toxicity, was not observed. No tumor or secondary hematologic disease was reported. Prophylactic radiotherapy remains the standard adjuvant treatment of stage I seminomas. Immediate tolerance is satisfactory and an increased risk for secondary cancer is negligible compared to the therapeutic benefit. However, strict monitoring and one cycle of carboplatin-based adjuvant chemotherapy are also effective.

  11. Analysis of quality control data of eight modern radiotherapy linear accelerators: the short- and long-term behaviours of the outputs and the reproducibility of quality control measurements

    NASA Astrophysics Data System (ADS)

    Kapanen, Mika; Tenhunen, Mikko; Hämäläinen, Tuomo; Sipilä, Petri; Parkkinen, Ritva; Järvinen, Hannu

    2006-07-01

    Quality control (QC) data of radiotherapy linear accelerators, collected by Helsinki University Central Hospital between the years 2000 and 2004, were analysed. The goal was to provide information for the evaluation and elaboration of QC of accelerator outputs and to propose a method for QC data analysis. Short- and long-term drifts in outputs were quantified by fitting empirical mathematical models to the QC measurements. Normally, long-term drifts were well (<=1%) modelled by either a straight line or a single-exponential function. A drift of 2% occurred in 18 ± 12 months. The shortest drift times of only 2-3 months were observed for some new accelerators just after the commissioning but they stabilized during the first 2-3 years. The short-term reproducibility and the long-term stability of local constancy checks, carried out with a sealed plane parallel ion chamber, were also estimated by fitting empirical models to the QC measurements. The reproducibility was 0.2-0.5% depending on the positioning practice of a device. Long-term instabilities of about 0.3%/month were observed for some checking devices. The reproducibility of local absorbed dose measurements was estimated to be about 0.5%. The proposed empirical model fitting of QC data facilitates the recognition of erroneous QC measurements and abnormal output behaviour, caused by malfunctions, offering a tool to improve dose control.

  12. Descriptive Analysis of Oligometastatic Lesions Treated With Curative-Intent Stereotactic Body Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Milano, Michael T.; Katz, Alan W.; Schell, Michael C.

    Purpose: To characterize oligometastases in patients enrolled on two prospective pilot studies, treating oligometastases with hypofractionated stereotactic body radiotherapy and stereotactic radiosurgery to cranial lesions. Methods and Materials: We describe the characteristics and local control (LC) of 293 lesions in 121 patients with five or fewer metastases treated with stereotactic body radiation and/or cranial stereotactic radiosurgery. For each lesion, the primary cancer site, tumor histology, site of metastasis, gross tumor volume, and prescribed dose were ascertained. The prescribed dose is expressed by the biologically effective dose in 2-Gy fractions (BED2), calculated using the linear quadratic model, assuming an {alpha}/{beta} ratiomore » of 10. Results: Lung lesions were significantly smaller than other lesions in our cohort, whereas liver lesions were significantly larger, possibly reflecting a detection and/or referral bias. The 2-year and 4-year tumor LC rates were 77% and 73% respectively. A larger gross tumor volume was significantly (p < 0.0001) correlated with worse lesion LC. Lesions originating from primary pancreatic, biliary or liver cancer exhibited significantly poorer LC, as did lesions from colorectal cancer. Lesions from breast cancer were better controlled. A higher BED2 did not correlate with improved tumor control. Conclusions: Stereotactic body radiation to aggressively treat oligometastatic lesions results in good local tumor control. Bulkier lesions are more difficult to control and may benefit from dose escalation.« less

  13. Accelerated versus conventional fractionated postoperative radiotherapy for advanced head and neck cancer: results of a multicenter Phase III study.

    PubMed

    Sanguineti, Giuseppe; Richetti, Antonella; Bignardi, Mario; Corvo', Renzo; Gabriele, Pietro; Sormani, Maria Pia; Antognoni, Paolo

    2005-03-01

    To determine whether, in the postoperative setting, accelerated fractionation (AF) radiotherapy (RT) yields a superior locoregional control rate compared with conventional fractionation (CF) RT in locally advanced squamous cell carcinomas of the oral cavity, oropharynx, larynx, or hypopharynx. Patients from four institutions with one or more high-risk features (pT4, positive resection margins, pN >1, perineural/lymphovascular invasion, extracapsular extension, subglottic extension) after surgery were randomly assigned to either RT with one daily session of 2 Gy up to 60 Gy in 6 weeks or AF. Accelerated fractionation consisted of a "biphasic concomitant boost" schedule, with the boost delivered during the first and last weeks of treatment, to deliver 64 Gy in 5 weeks. Informed consent was obtained. The primary endpoint of the study was locoregional control. Analysis was on an intention-to-treat basis. From March 1994 to August 2000, 226 patients were randomized. At a median follow-up of 30.6 months (range, 0-110 months), 2-year locoregional control estimates were 80% +/- 4% for CF and 78% +/- 5% for AF (p = 0.52), and 2-year overall survival estimates were 67% +/- 5% for CF and 64% +/- 5% for AF (p = 0.84). The lack of difference in outcome between the two treatment arms was confirmed by multivariate analysis. However, interaction analysis with median values as cut-offs showed a trend for improved locoregional control for those patients who had a delay in starting RT and who were treated with AF compared with those with a similar delay but who were treated with CF (hazard ratio = 0.5, 95% confidence interval 0.2-1.1). Fifty percent of patients treated with AF developed confluent mucositis, compared with only 27% of those treated with CF (p = 0.006). However, mucositis duration was not different between arms. Although preliminary, actuarial Grade 3+ late toxicity estimates at 2 years were 18% +/- 4% and 27% +/- 6% for CF and AF, respectively (p = 0.10). Accelerated

  14. Impact of conventional fractionated RT to pelvic lymph nodes and dose-escalated hypofractionated RT to prostate gland using IMRT treatment delivery in high-risk prostate cancer

    NASA Astrophysics Data System (ADS)

    Pervez, Nadeem

    Prostate cancer is the most common cancer among Canadian men. The standard treatment in high-risk category is radical radiation, with androgen suppression treatment (AST). Significant disease progression is reported despite this approach. Radiation dose escalation has been shown to improve disease-free survival; however, it results in higher toxicities. Hypofractionated radiation schedules (larger dose each fraction in shorter overall treatment time) are expected to deliver higher biological doses. A hypofractionated scheme was used in this study to escalate radiation doses with AST. Treatment was well tolerated acutely. Early results of self-administered quality of life reported by patients shows a decrease in QOL which is comparable to other treatment schedules. Significant positional variation of the prostate was observed during treatment. Therefore, we suggest daily target verification to avoid a target miss. Initial late effects are reasonable and early treatment outcomes are promising. Longer follow-up is required for full outcomes assessments.

  15. Hypofractionated Dose-Painting Intensity Modulated Radiation Therapy With Chemotherapy for Nasopharyngeal Carcinoma: A Prospective Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bakst, Richard L.; Lee, Nancy; Pfister, David G.

    2011-05-01

    Purpose: To evaluate the feasibility of dose-painting intensity-modulated radiation therapy (DP-IMRT) with a hypofractionated regimen to treat nasopharyngeal carcinoma (NPC) with concomitant toxicity reduction. Methods and Materials: From October 2002 through April 2007, 25 newly diagnosed NPC patients were enrolled in a prospective trial. DP-IMRT was prescribed to deliver 70.2 Gy using 2.34-Gy fractions to the gross tumor volume for the primary and nodal sites while simultaneously delivering 54 Gy in 1.8-Gy fractions to regions at risk of microscopic disease. Patients received concurrent and adjuvant platin-based chemotherapy similar to the Intergroup 0099 trial. Results: Patient and disease characteristics are asmore » follows: median age, 46; 44% Asian; 68% male; 76% World Health Organization III; 20% T1, 52% T2, 16% T3, 12% T4; 20% N0, 36% N1, 36% N2, 8% N3. With median follow-up of 33 months, 3-year local control was 91%, regional control was 91%, freedom from distant metastases was 91%, and overall survival was 89%. The average mean dose to each cochlea was 43 Gy. With median audiogram follow-up of 14 months, only one patient had clinically significant (Grade 3) hearing loss. Twelve percent of patients developed temporal lobe necrosis; one patient required surgical resection. Conclusions: Preliminary findings using a hypofractionated DP-IMRT regimen demonstrated that local control, freedom from distant metastases, and overall survival compared favorably with other series of IMRT and chemotherapy. The highly conformal boost to the tumor bed resulted low rates of severe ototoxicity (Grade 3-4). However, the incidence of in-field brain radiation necrosis indicates that 2.34 Gy per fraction is not safe in this setting.« less

  16. Radiotherapy of Langerhans' Cell Histiocytosis : Results and Implications of a National Patterns-of-Care Study.

    PubMed

    Olschewski, Thomas; Seegenschmiedt, Michael Heinrich

    2006-11-01

    This patterns-of-care study was performed to define the current clinical experience with radiotherapy of Langerhans' cell histiocytosis in adults in Germany and to define open questions resulting from this study. A standardized questionnaire was sent to 198 German radiotherapy institutions. Data about patient characteristics, stage of disease, practice and fractionation of radiotherapy, outcome of therapy, etc. were systematically evaluated. 123 of 198 institutions answered the complete questionnaire (62.1%). Only 23 of the 123 institutions (18.7%) reported experience with radiotherapy of Langerhans' cell histiocytosis of adults. 18 institutions with 98 patients were evaluable. The majority of patients (72 of 98) was treated on a linear accelerator. The median single dose of radiotherapy was 2 Gy, while the median total dose was 24 Gy. 81 of 89 evaluable patients (91%) reached a local control of the treated lesion(s), 69 of those had a complete remission. Eight of 89 patients (9%) developed an in-field recurrence. 87.8% of patients experienced no acute and 97% of patients no late side effects of radiotherapy. Clinical experience with radiotherapy of Langerhans' cell histiocytosis in adults in Germany is still very limited. Nevertheless, the clinical results-with high remission and local control rates-confirm the effectiveness of radiotherapy in the multidisciplinary treatment of this disease. Due to the small number of patients in this study despite higher incidence rates, the knowledge of this disease has to be multiplied in Germany. Future patients should be systematically included into a prospective radiotherapy registry.

  17. Infrastructure and equipment for radiation oncology in the Spanish National Health System: analysis of external beam radiotherapy 2015-2020.

    PubMed

    Rodríguez, A; Algara, M; Monge, D; López-Torrecilla, J; Caballero, F; Morera, R; Escó, R; Pérez-Montero, H; Ferrer, C; Lara, P C

    2018-03-01

    Planning for radiation oncology requires reliable estimates of both demand for radiotherapy and availability of technological resources. This study compares radiotherapy resources in the 17 regions of the decentralised Spanish National Health System (SNHS). The Sociedad Española de Oncología Radioterápica (SEOR) performed a cross-sectional survey of all Spanish radiation oncology services (ROS) in 2015. We collected data on SNHS radiotherapy units, recording the year of installation, specific features of linear accelerators (LINACs) and other treatment units, and radiotherapeutic techniques implemented by region. Any machine over 10 years old or lacking a multileaf collimator or portal imaging system was considered obsolete. We performed a k-means clustering analysis using the Hartigan-Wong method to test associations between the gross domestic regional product (GDRP), the number of LINACs per million population and the percentage of LINACs over 10 years old. The SNHS controls 72 (61%) of the 118 Spanish ROS and has 180 LINACs, or 72.5% of the total public and private resources. The mean rate of LINACs per million population is 3.9 for public ROS, and 42% (n = 75) of the public accelerators were obsolete in 2015: 61 due to age and 14 due to technological capability. There was considerable regional variation in terms of the number and technological capacity of radiotherapy units; correlation between GRDP and resource availability was moderate. Despite improvements, new investments are still needed to replace obsolete units and increase access to modern radiotherapy. Regular analysis of ROS in each Spanish region is the only strategy for monitoring progress in radiotherapy capacity.

  18. Green tea extract (epigallocatechin-3-gallate) reduces efficacy of radiotherapy on prostate cancer cells.

    PubMed

    Thomas, Francis; Holly, Jeff M P; Persad, Rajendra; Bahl, Amit; Perks, Claire M

    2011-08-01

    To assess the influence of epigallocatechin-3-gallate (EGCG) on the efficacy of ionizing radiation on prostate cancer cells because of the increased use of dietary interventions, especially by patients with prostate cancer. Radiotherapy is used to treat localized prostate cancer. Some people consume green tea (EGCG) as a chemopreventive agent against prostate cancer. Green tea can act as an antioxidant and induce superoxide dismutase enzymes, which could scavenge the free oxygen radicals generated by radiotherapy. Prostate cancer cell line DU145 cells were treated with EGCG or radiotherapy, or both. Cell death was assessed using trypan blue cell counting, and apoptosis was confirmed by assessing poly (adenosine phosphate ribose) polymerase cleavage. The antioxidant potential was assessed using Western immunoblotting for manganese superoxide dismutase and copper zinc superoxide dismutase enzymes. Radiotherapy was delivered using a linear accelerator. Cell cycle analysis was performed using flow cytometry. Radiotherapy at 3.5 Gy induced a 5.9-fold increase in apoptosis of DU145 cells. Subapoptotic doses of EGCG (1.5-7.5 μM) significantly reduced ionizing radiation-induced apoptosis (P < .001), with the inhibitory effect of EGCG on ionizing radiation being most effective when added 30 minutes before radiotherapy (P < .001). In addition, when radiotherapy and EGCG were used together, an approximate 1.5-fold increase in manganese superoxide dismutase levels was seen compared with the control and a 2-fold increase compared with radiotherapy alone. Radiotherapy is effective in inducing apoptosis in DU145 cells, but its effect was significantly reduced in the presence of EGCG, and this was associated with an increase in the induction of manganese superoxide dismutase. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Phase 2 Trial of Accelerated, Hypofractionated Whole-Breast Irradiation of 39 Gy in 13 Fractions Followed by a Tumor Bed Boost Sequentially Delivering 9 Gy in 3 Fractions in Early-Stage Breast Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Ja Young; Jung, So-Youn; Lee, Seeyoun

    Purpose: To report a phase 2 trial of accelerated, hypofractionated whole-breast irradiation (AH-WBI) delivered as a daily dose of 3 Gy to the whole breast followed by a tumor bed boost. Methods and Materials: Two hundred seventy-six patients diagnosed with breast cancer (pT1-2 and pN0-1a) who had undergone breast-conserving surgery in which the operative margins were negative were treated with AH-WBI delivered as 39 Gy in 13 fractions of 3 Gy to the whole breast once daily over 5 consecutive working days, and 9 Gy in 3 sequential fractions of 3 Gy to a lumpectomy cavity, all within 3.2 weeks.more » Results: After a median follow-up period of 57 months (range: 27-75 months), the rate of 5-year locoregional recurrence was 1.4% (n=4), whereas that of disease-free survival was 97.4%. No grade 3 skin toxicity was reported during the follow-up period. Qualitative physician cosmetic assessments of good or excellent were noted in 82% of the patients at 2 months after the completion of AH-WBI. The global cosmetic outcome did not worsen over time, and a good or excellent cosmetic outcome was reported in 82% of the patients at 3 years. The mean pretreatment percentage breast retraction assessment was 12.00 (95% confidence interval [CI]: 11.14-12.86). The mean value of percentage breast retraction assessment increased to 13.99 (95% CI: 12.17-15.96) after 1 year and decreased to 13.54 (95% CI: 11.84-15.46) after 3 years but was not significant (P>.05). Conclusions: AH-WBI consisting of 39 Gy in 13 fractions followed by a tumor bed boost sequentially delivering 9 Gy in 3 fractions can be delivered with excellent disease control and tolerable skin toxicity in patients with early-stage breast cancer after breast-conserving surgery.« less

  20. Phase 2 trial of accelerated, hypofractionated whole-breast irradiation of 39 Gy in 13 fractions followed by a tumor bed boost sequentially delivering 9 Gy in 3 fractions in early-stage breast cancer.

    PubMed

    Kim, Ja Young; Jung, So-Youn; Lee, Seeyoun; Kang, Han-Sung; Lee, Eun Sook; Park, In Hae; Lee, Keun Seok; Ro, Jungsil; Lee, Nam Kwon; Shin, Kyung Hwan

    2013-12-01

    To report a phase 2 trial of accelerated, hypofractionated whole-breast irradiation (AH-WBI) delivered as a daily dose of 3 Gy to the whole breast followed by a tumor bed boost. Two hundred seventy-six patients diagnosed with breast cancer (pT1-2 and pN0-1a) who had undergone breast-conserving surgery in which the operative margins were negative were treated with AH-WBI delivered as 39 Gy in 13 fractions of 3 Gy to the whole breast once daily over 5 consecutive working days, and 9 Gy in 3 sequential fractions of 3 Gy to a lumpectomy cavity, all within 3.2 weeks. After a median follow-up period of 57 months (range: 27-75 months), the rate of 5-year locoregional recurrence was 1.4% (n=4), whereas that of disease-free survival was 97.4%. No grade 3 skin toxicity was reported during the follow-up period. Qualitative physician cosmetic assessments of good or excellent were noted in 82% of the patients at 2 months after the completion of AH-WBI. The global cosmetic outcome did not worsen over time, and a good or excellent cosmetic outcome was reported in 82% of the patients at 3 years. The mean pretreatment percentage breast retraction assessment was 12.00 (95% confidence interval [CI]: 11.14-12.86). The mean value of percentage breast retraction assessment increased to 13.99 (95% CI: 12.17-15.96) after 1 year and decreased to 13.54 (95% CI: 11.84-15.46) after 3 years but was not significant (P>.05). AH-WBI consisting of 39 Gy in 13 fractions followed by a tumor bed boost sequentially delivering 9 Gy in 3 fractions can be delivered with excellent disease control and tolerable skin toxicity in patients with early-stage breast cancer after breast-conserving surgery. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Combined treatment of anaplastic thyroid carcinoma with surgery, chemotherapy, and hyperfractionated accelerated external radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    De Crevoisier, Renaud; Baudin, Eric; Bachelot, Anne

    Purpose: To analyze a prospective protocol combining surgery, chemotherapy (CT), and hyperfractionated accelerated radiotherapy (RT) in anaplastic thyroid carcinoma. Methods and materials: Thirty anaplastic thyroid carcinoma patients (mean age, 59 years) were treated during 1990-2000. Tumor extended beyond the capsule gland in 26 patients, with tracheal extension in 8. Lymph node metastases were present in 18 patients and lung metastases in 6. Surgery was performed before RT-CT in 20 patients and afterwards in 4. Two cycles of doxorubicin (60 mg/m{sup 2}) and cisplatin (120 mg/m{sup 2}) were delivered before RT and four cycles after RT. RT consisted of two dailymore » fractions of 1.25 Gy, 5 days per week to a total dose of 40 Gy to the cervical lymph node areas and the superior mediastinum. Results: Acute toxicity (World Health Organization criteria) was Grade 3 or 4 pharyngoesophagitis in 10 patients; Grade 4 neutropenia in 21, with infection in 13; and Grade 3 or 4 anemia and thrombopenia in 8 and 4, respectively. At the end of the treatment, a complete local response was observed in 19 patients. With a median follow-up of 45 months (range, 12-78 months), 7 patients were alive in complete remission, of whom 6 had initially received a complete tumor resection. Overall survival rate at 3 years was 27% (95% confidence interval 10-44%) and median survival 10 months. In multivariate analysis, tracheal extension and macroscopic complete tumor resection were significant factors in overall survival. Death was related to local progression in 5% of patients, to distant metastases in 68%, and to both in 27%. Conclusions: Main toxicity was hematologic. High long-term survival was obtained when RT-CT was given after complete surgery. This protocol avoided local tumor progression, and death was mainly caused by distant metastases.« less

  2. Intraoperative radiotherapy. Literature updating with an overview of results presented at the 6th International Symposium of Intraoperative Radiation Therapy.

    PubMed

    Calvo, F A; Santos, M; Azinovic, I

    1998-01-01

    Intraoperative radiotherapy is a technique that can be integrated into multidisciplinary treatment strategies in oncology. A radiation boost delivered with high energy electron beams can intensify locoregional antitumor therapy in patients undergoing cancer surgery. Intraoperative radiotherapy can increase the therapeutic index of the conventional combination of surgery and radiotherapy by improving the precision of radiation dose location, while decreasing the normal tissue damage in mobile structures and enhancing the biological effect of radiation when combined with surgical debulking. Intraoperative radiotherapy has been extensively investigated in clinical oncology in the last 15 years. Commercially available linear accelerators require minimal changes to be suitable for intraoperative radiotherapy. Its successful implementation in clinical protocols depends on the support given by the single institutions and on a clinical research-oriented mentality. Tumors where intraoperative radiotherapy as a treatment component has shown promising rates of local control include locally advanced rectal, gastric and gynecologic cancer, bone and soft tissue sarcoma. Intraoperative radiotherapy can be applied to brain tumors, head and neck cancer, NSCLC and pancreatic carcinoma.

  3. Verification of respiratory-gated radiotherapy with new real-time tumour-tracking radiotherapy system using cine EPID images and a log file

    NASA Astrophysics Data System (ADS)

    Shiinoki, Takehiro; Hanazawa, Hideki; Yuasa, Yuki; Fujimoto, Koya; Uehara, Takuya; Shibuya, Keiko

    2017-02-01

    A combined system comprising the TrueBeam linear accelerator and a new real-time tumour-tracking radiotherapy system, SyncTraX, was installed at our institution. The objectives of this study are to develop a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine electronic portal image device (EPID) images and a log file and to verify this treatment in clinical cases. Respiratory-gated radiotherapy was performed using TrueBeam and the SyncTraX system. Cine EPID images and a log file were acquired for a phantom and three patients during the course of the treatment. Digitally reconstructed radiographs (DRRs) were created for each treatment beam using a planning CT set. The cine EPID images, log file, and DRRs were analysed using a developed software. For the phantom case, the accuracy of the proposed method was evaluated to verify the respiratory-gated radiotherapy. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker used as an internal surrogate were calculated to evaluate the gating accuracy and set-up uncertainty in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions. The proposed method achieved high accuracy for the phantom verification. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker were  ⩽3 mm and  ±3 mm in the SI, AP, and LR directions. We proposed a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine EPID images and a log file and showed that this treatment is performed with high accuracy in clinical cases. This work was partly presented at the 58th Annual meeting of American Association of Physicists in Medicine.

  4. Germline glutathione S-transferase variants in breast cancer: Relation to diagnosis and cutaneous long-term adverse effects after two fractionation patterns of radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Edvardsen, Hege; Kristensen, Vessela N.; Medical Faculty, University of Oslo, Oslo

    Purpose: To explore whether certain glutathione S-transferase (GST) polymorphisms are associated with an increased risk of breast cancer or the level of radiation-induced adverse effects after two fractionation patterns of adjuvant radiotherapy. Methods and Materials: The prevalence of germline polymorphic variants in GSTM1, GSTP1, and GSTT1 was determined in 272 breast cancer patients and compared with that in a control group of 270 women from the general population with no known history of breast cancer. The genetic variants were determined using multiplex polymerase chain reaction followed by restriction enzyme fragment analysis. In 253 of the patients surveyed for radiotherapy-induced sidemore » effects after a median observation time of 13.7 years (range, 7-22.8 years), the genotypes were related to the long-term effects observed after two fractionation patterns (treatment A, 4.3 Gy in 10 fractions for 156 patients; and treatment B, 2.5 Gy in 20 fractions for 97; both administered within a 5-week period). Results: None of the GST polymorphisms conferred an increased risk of breast cancer, either alone or in combination. Compared with treatment B, treatment A was followed by an increased level of moderate to severe radiation-induced side effects for all the endpoints studied (i.e., degree of telangiectasia, subcutaneous fibrosis and atrophy, lung fibrosis, costal fractures, and pleural thickening; p <0.001 for all endpoints). A significant association was found between the level of pleural thickening and the GSTP1 Ile105Val variant. Conclusion: The results of this study have illustrated the impact of hypofractionation on the level of adverse effects and indicated that the specific alleles of GSTP1, M1, and T1 studied here may be significant in determining the level of adverse effects after radiotherapy.« less

  5. Predicting location of recurrence using FDG, FLT, and Cu-ATSM PET in canine sinonasal tumors treated with radiotherapy

    NASA Astrophysics Data System (ADS)

    Bradshaw, Tyler; Fu, Rau; Bowen, Stephen; Zhu, Jun; Forrest, Lisa; Jeraj, Robert

    2015-07-01

    Dose painting relies on the ability of functional imaging to identify resistant tumor subvolumes to be targeted for additional boosting. This work assessed the ability of FDG, FLT, and Cu-ATSM PET imaging to predict the locations of residual FDG PET in canine tumors following radiotherapy. Nineteen canines with spontaneous sinonasal tumors underwent PET/CT imaging with radiotracers FDG, FLT, and Cu-ATSM prior to hypofractionated radiotherapy. Therapy consisted of 10 fractions of 4.2 Gy to the sinonasal cavity with or without an integrated boost of 0.8 Gy to the GTV. Patients had an additional FLT PET/CT scan after fraction 2, a Cu-ATSM PET/CT scan after fraction 3, and follow-up FDG PET/CT scans after radiotherapy. Following image registration, simple and multiple linear and logistic voxel regressions were performed to assess how well pre- and mid-treatment PET imaging predicted post-treatment FDG uptake. R2 and pseudo R2 were used to assess the goodness of fits. For simple linear regression models, regression coefficients for all pre- and mid-treatment PET images were significantly positive across the population (P < 0.05). However, there was large variability among patients in goodness of fits: R2 ranged from 0.00 to 0.85, with a median of 0.12. Results for logistic regression models were similar. Multiple linear regression models resulted in better fits (median R2 = 0.31), but there was still large variability between patients in R2. The R2 from regression models for different predictor variables were highly correlated across patients (R ≈ 0.8), indicating tumors that were poorly predicted with one tracer were also poorly predicted by other tracers. In conclusion, the high inter-patient variability in goodness of fits indicates that PET was able to predict locations of residual tumor in some patients, but not others. This suggests not all patients would be good candidates for dose painting based on a single biological target.

  6. Predicting location of recurrence using FDG, FLT, and Cu-ATSM PET in canine sinonasal tumors treated with radiotherapy.

    PubMed

    Bradshaw, Tyler; Fu, Rau; Bowen, Stephen; Zhu, Jun; Forrest, Lisa; Jeraj, Robert

    2015-07-07

    Dose painting relies on the ability of functional imaging to identify resistant tumor subvolumes to be targeted for additional boosting. This work assessed the ability of FDG, FLT, and Cu-ATSM PET imaging to predict the locations of residual FDG PET in canine tumors following radiotherapy. Nineteen canines with spontaneous sinonasal tumors underwent PET/CT imaging with radiotracers FDG, FLT, and Cu-ATSM prior to hypofractionated radiotherapy. Therapy consisted of 10 fractions of 4.2 Gy to the sinonasal cavity with or without an integrated boost of 0.8 Gy to the GTV. Patients had an additional FLT PET/CT scan after fraction 2, a Cu-ATSM PET/CT scan after fraction 3, and follow-up FDG PET/CT scans after radiotherapy. Following image registration, simple and multiple linear and logistic voxel regressions were performed to assess how well pre- and mid-treatment PET imaging predicted post-treatment FDG uptake. R(2) and pseudo R(2) were used to assess the goodness of fits. For simple linear regression models, regression coefficients for all pre- and mid-treatment PET images were significantly positive across the population (P < 0.05). However, there was large variability among patients in goodness of fits: R(2) ranged from 0.00 to 0.85, with a median of 0.12. Results for logistic regression models were similar. Multiple linear regression models resulted in better fits (median R(2) = 0.31), but there was still large variability between patients in R(2). The R(2) from regression models for different predictor variables were highly correlated across patients (R ≈ 0.8), indicating tumors that were poorly predicted with one tracer were also poorly predicted by other tracers. In conclusion, the high inter-patient variability in goodness of fits indicates that PET was able to predict locations of residual tumor in some patients, but not others. This suggests not all patients would be good candidates for dose painting based on a single biological target.

  7. A comparison between surgical resection in combination with WBRT or hypofractionated stereotactic irradiation in the treatment of solitary brain metastases.

    PubMed

    Lindvall, Peter; Bergström, Per; Löfroth, Per-Olov; Tommy Bergenheim, A

    2009-09-01

    The standard treatment of solitary brain metastases previously has been tumour resection in combination with whole-brain radiation therapy (WBRT). Stereotactic radiotherapy has emerged as a non-invasive treatment option especially for small brain metastases. We now report our results on resection + WBRT or hypofractionated stereotactic irradiation (HCSRT) in the treatment of solitary brain metastases. Between 1993 and 2004 patients with metastatic cancer and solitary brain metastases were selected for surgical resection + WBRT or HCSRT alone at the Umeå University Hospital. Fifty-nine patients were treated with surgical resection + WBRT (34 male, 25 female, mean age 63.3 years). Forty-seven patients were treated with HCSRT alone (15 male, 32 female, mean age 64.9 years). In patients followed radiologically, 28% treated with resection + WBRT showed a local recurrence after a median time of 8.0 months, whereas there was a lack of local control in 16% in the HCSRT group after a median time of 3.0 months. There was a significantly longer survival time for patients treated with resection + WBRT (median 7.9, mean 12.9 months) compared to HCSRT (median 5.0, mean 7.6 months). Even in patients with a tumour volume <10 cc, there was a significantly longer survival in favour of resection + WBRT (median 8.4, mean 17.4 months) compared to HCSRT (median 5.0, mean 7.9 months). This retrospective and non-randomised study indicates that surgical resection in combination with WBRT may be an option even for small brain metastases suitable for treatment with HCSRT. Since survival and local control following resection + WBRT was at least as favourable as compared to HCSRT alone, tumour location and expected neurological outcome may be the strongest aspect when selecting treatment modality.

  8. Accelerated partial breast irradiation using 3D conformal radiotherapy: toxicity and cosmetic outcome.

    PubMed

    Gatti, M; Ponzone, R; Bresciani, S; Panaia, R; Kubatzki, F; Maggiorotto, F; Di Virgilio, M R; Salatino, A; Baiotto, B; Montemurro, F; Stasi, M; Gabriele, P

    2013-12-01

    The aim of this paper is to analyze the incidence of acute and late toxicity and cosmetic outcome in breast cancer patients submitted to breast conserving surgery and three-dimensional conformal radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI). 84 patients were treated with 3D-CRT for APBI. This technique was assessed in patients with low risk stage I breast cancer enrolled from September 2005 to July 2011. The prescribed dose was 34/38.5 Gy delivered in 10 fractions twice daily over 5 consecutive days. Four to five no-coplanar 6 MV beams were used. In all CT scans Gross Tumor Volume (GTV) was defined around the surgical clips. A 1.5 cm margin was added by defining a Clinical Target Volume (CTV). A margin of 1 cm was added to CTV to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the NSABP/RTOG protocol. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed using the Harvard scale. Median patient age was 66 years (range 51-87). Median follow-up was 36.5 months (range 13-83). The overall incidence of acute skin toxicities was 46.4% for grade 1 and 1% for grade 2. The incidence of late toxicity was 16.7% for grade 1, 2.4% for grade 2 and 3.6% for grade 3. No grade 4 toxicity was observed. The most pronounced grade 2 late toxicity was telangiectasia, developed in three patients. Cosmetics results were excellent for 52%, good for 42%, fair for 5% and poor for 1% of the patients. There was no statistical correlation between toxicity rates and prescribed doses (p = 0.33) or irradiated volume (p = 0.45). APBI using 3D-CRT is technically feasible with very low acute and late toxicity. Long-term results are needed to assess its efficacy in reducing the incidence of breast relapse. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Association between access to accelerated partial breast irradiation and use of adjuvant radiotherapy.

    PubMed

    Wang, Elyn H; Park, Henry S; Rutter, Charles E; Gross, Cary P; Soulos, Pamela R; Yu, James B; Evans, Suzanne B

    2017-02-01

    The current study was performed to determine whether access to facilities performing accelerated partial breast irradiation (APBI) is associated with differences in the use of adjuvant radiotherapy (RT). Using the National Cancer Data Base, the authors performed a retrospective study of women aged ≥50 years who were diagnosed with early-stage breast cancer between 2004 and 2013 and treated with breast-conserving surgery (BCS). Facilities performing APBI in ≥10% of their eligible patients within a given year were defined as APBI facilities whereas those not performing APBI were defined as non-APBI facilities. All other facilities were excluded. The authors identified independent factors associated with RT use using multivariable logistic regression with clustering in the overall sample as well as in subsets of patients with standard-risk invasive cancer, low-risk invasive cancer, and ductal carcinoma in situ. Among 222,544 patients, 76.6% underwent BCS plus RT and 23.4% underwent BCS alone. The likelihood of RT receipt in the overall sample did not appear to differ significantly between APBI and non-APBI facilities (adjusted odds ratio [AOR], 1.02; P = .61). Subgroup multivariable analysis demonstrated that among patients with standard-risk invasive cancer, there was no association between evaluation at an APBI facility and receipt of RT (AOR, 0.98; P = .69). However, patients with low-risk invasive cancer were found to be significantly more likely to receive RT (54.4% vs 59.5%; AOR, 1.22 [P<.001]), whereas patients with ductal carcinoma in situ were less likely to receive RT (56.9% vs 55.3%; AOR, 0.89 [P = .04]) at APBI facilities. Patients who were eligible for observation were more likely to receive RT in APBI facilities but no difference was observed among patients with standard-risk invasive cancer who would most benefit from RT. Cancer 2017;123:502-511. © 2016 American Cancer Society. © 2016 American Cancer Society.

  10. New technologies in radiation therapy: ensuring patient safety, radiation safety and regulatory issues in radiation oncology.

    PubMed

    Amols, Howard I

    2008-11-01

    New technologies such as intensity modulated and image guided radiation therapy, computer controlled linear accelerators, record and verify systems, electronic charts, and digital imaging have revolutionized radiation therapy over the past 10-15 y. Quality assurance (QA) as historically practiced and as recommended in reports such as American Association of Physicists in Medicine Task Groups 40 and 53 needs to be updated to address the increasing complexity and computerization of radiotherapy equipment, and the increased quantity of data defining a treatment plan and treatment delivery. While new technology has reduced the probability of many types of medical events, seeing new types of errors caused by improper use of new technology, communication failures between computers, corrupted or erroneous computer data files, and "software bugs" are now being seen. The increased use of computed tomography, magnetic resonance, and positron emission tomography imaging has become routine for many types of radiotherapy treatment planning, and QA for imaging modalities is beyond the expertise of most radiotherapy physicists. Errors in radiotherapy rarely result solely from hardware failures. More commonly they are a combination of computer and human errors. The increased use of radiosurgery, hypofractionation, more complex intensity modulated treatment plans, image guided radiation therapy, and increasing financial pressures to treat more patients in less time will continue to fuel this reliance on high technology and complex computer software. Clinical practitioners and regulatory agencies are beginning to realize that QA for new technologies is a major challenge and poses dangers different in nature than what are historically familiar.

  11. Three-year outcomes of a once daily fractionation scheme for accelerated partial breast irradiation (APBI) using 3-D conformal radiotherapy (3D-CRT)

    PubMed Central

    Goyal, Sharad; Daroui, Parima; Khan, Atif J; Kearney, Thomas; Kirstein, Laurie; Haffty, Bruce G

    2013-01-01

    The aim of this study was to report 3-year outcomes of toxicity, cosmesis, and local control using a once daily fractionation scheme (49.95 Gy in 3.33 Gy once daily fractions) for accelerated partial breast irradiation (APBI) using three-dimensional conformal radiotherapy (3D-CRT). Between July 2008 and August 2010, women aged ≥40 years with ductal carcinoma in situ or node-negative invasive breast cancer ≤3 cm in diameter, treated with breast-conserving surgery achieving negative margins, were accrued to a prospective study. Women were treated with APBI using 3–5 photon beams, delivering 49.95 Gy over 15 once daily fractions over 3 weeks. Patients were assessed for toxicities, cosmesis, and local control rates before APBI and at specified time points. Thirty-four patients (mean age 60 years) with Tis 0 (n = 9) and T1N0 (n = 25) breast cancer were treated and followed up for an average of 39 months. Only 3% (1/34) patients experienced a grade 3 subcutaneous fibrosis and breast edema and 97% of the patients had good/excellent cosmetic outcome at 3 years. The 3-year rate of ipsilateral breast tumor recurrence (IBTR) was 0% while the rate of contralateral breast events was 6%. The 3-year disease-free survival (DFS), overall survival (OS), and breast cancer-specific survival (BCSS) was 94%, 100%, and 100%, respectively. Our novel accelerated partial breast fractionation scheme of 15 once daily fractions of 3.33 Gy (49.95 Gy total) is a remarkably well-tolerated regimen of 3D-CRT-based APBI. A larger cohort of patients is needed to further ascertain the toxicity of this accelerated partial breast regimen. PMID:24403270

  12. Carbon Beam Radio-Therapy and Research Activities at HIMAC

    NASA Astrophysics Data System (ADS)

    Kanazawa, Mitsutaka

    2007-05-01

    Radio-therapy with carbon ion beam has been carried out since 1994 at HIMAC (Heavy Ion Medical Accelerator in Chiba) in NIRS (National Institute of Radiological Sciences). Now, many types of tumors can be treated with carbon beam with excellent local controls of the tumors. Stimulated with good clinical results, requirement of the dedicated compact facility for carbon beam radio-therapy is increased. To realize this requirement, design study of the facility and the R&D's of the key components in this design are promoted by NIRS. According successful results of these activities, the dedicated compact facility will be realized in Gunma University. In this facility, the established irradiation method is expected to use, which is passive irradiation method with wobbler magnets and ridge filter. In this presentation, above R&D's will be presented together with clinical results and basic research activities at HIMAC.

  13. Short communication: timeline of radiation-induced kidney function loss after stereotactic ablative body radiotherapy of renal cell carcinoma as evaluated by serial (99m)Tc-DMSA SPECT/CT.

    PubMed

    Jackson, Price; Foroudi, Farshad; Pham, Daniel; Hofman, Michael S; Hardcastle, Nicholas; Callahan, Jason; Kron, Tomas; Siva, Shankar

    2014-11-26

    Stereotactic ablative body radiotherapy (SABR) has been proposed as a definitive treatment for patients with inoperable primary renal cell carcinoma. However, there is little documentation detailing the radiobiological effects of hypofractionated radiation on healthy renal tissue. In this study we describe a methodology for assessment of regional change in renal function in response to single fraction SABR of 26 Gy. In a patient with a solitary kidney, detailed follow-up of kidney function post-treatment was determined through 3-dimensional SPECT/CT imaging and (51)Cr-EDTA measurements. Based on measurements of glomerular filtration rate, renal function declined rapidly by 34% at 3 months, plateaued at 43% loss at 12 months, with minimal further decrease to 49% of baseline by 18 months. The pattern of renal functional change in (99m)Tc-DMSA uptake on SPECT/CT imaging correlates with dose delivered. This study demonstrates a dose effect relationship of SABR with loss of kidney function.

  14. Quality management system in radiotherapy in the light of regulations applicable in Poland

    PubMed Central

    2012-01-01

    The need to establish conditions for safe irradiation was noted in Poland back in 1986 in the Atomic Law, but for over 16 years no regulations regarding this aspect were passed. The radiological incident in Bialystok (Poland) in 2001 undeniably accelerated the implementation of new legal regulations. Nevertheless, in the absence of national guidelines until 2002, most health care institutions resorted to the quality management system (QMS) model proposed by the ISO norm 9001:2000. Eventually, practice proved the theory and the aforementioned model was also implemented into Polish acts of law defining basic requirements for QMS in radiotherapy. The aim of this work is to review current national regulations regarding QMS in radiotherapy, in particular those referring to standard procedures, the establishment of a commission for procedures and performance of external and internal clinical audits in oncological radiotherapy, as well as to present the process of their implementation into the practice of health care institutions. PMID:23788867

  15. Tumour regression of uveal melanoma after ruthenium-106 brachytherapy or stereotactic radiotherapy with gamma knife or linear accelerator.

    PubMed

    Georgopoulos, Michael; Zehetmayer, Martin; Ruhswurm, Irene; Toma-Bstaendig, Sabine; Ségur-Eltz, Nikolaus; Sacu, Stefan; Menapace, Rupert

    2003-01-01

    This study assesses differences in relative tumour regression and internal acoustic reflectivity after 3 methods of radiotherapy for uveal melanoma: (1) brachytherapy with ruthenium-106 radioactive plaques (RU), (2) fractionated high-dose gamma knife stereotactic irradiation in 2-3 fractions (GK) or (3) fractionated linear-accelerator-based stereotactic teletherapy in 5 fractions (Linac). Ultrasound measurements of tumour thickness and internal reflectivity were performed with standardised A scan pre-operatively and 3, 6, 9, 12, 18, 24 and 36 months postoperatively. Of 211 patients included in the study, 111 had a complete 3-year follow-up (RU: 41, GK: 37, Linac: 33). Differences in tumour thickness and internal reflectivity were assessed with analysis of variance, and post hoc multiple comparisons were calculated with Tukey's honestly significant difference test. Local tumour control was excellent with all 3 methods (>93%). At 36 months, relative tumour height reduction was 69, 50 and 30% after RU, GK and Linac, respectively. In all 3 treatment groups, internal reflectivity increased from about 30% initially to 60-70% 3 years after treatment. Brachytherapy with ruthenium-106 plaques results in a faster tumour regression as compared to teletherapy with gamma knife or Linac. Internal reflectivity increases comparably in all 3 groups. Besides tumour growth arrest, increasing internal reflectivity is considered as an important factor indicating successful treatment. Copyright 2003 S. Karger AG, Basel

  16. Three-dimensional intrafractional internal target motions in accelerated partial breast irradiation using three-dimensional conformal external beam radiotherapy.

    PubMed

    Hirata, Kimiko; Yoshimura, Michio; Mukumoto, Nobutaka; Nakamura, Mitsuhiro; Inoue, Minoru; Sasaki, Makoto; Fujimoto, Takahiro; Yano, Shinsuke; Nakata, Manabu; Mizowaki, Takashi; Hiraoka, Masahiro

    2017-07-01

    We evaluated three-dimensional intrafractional target motion, divided into respiratory-induced motion and baseline drift, in accelerated partial breast irradiation (APBI). Paired fluoroscopic images were acquired simultaneously using orthogonal kV X-ray imaging systems at pre- and post-treatment for 23 patients who underwent APBI with external beam radiotherapy. The internal target motion was calculated from the surgical clips placed around the tumour cavity. The peak-to-peak respiratory-induced motions ranged from 0.6 to 1.5mm in all directions. A systematic baseline drift of 1.5mm towards the posterior direction and a random baseline drift of 0.3mm in the lateral-medial and cranial-caudal directions were observed. The baseline for an outer tumour cavity drifted towards the lateral and posterior directions, and that for an upper tumour cavity drifted towards the cranial direction. Moderate correlations were observed between the posterior baseline drift and the patients' physical characteristics. The posterior margin for intrafractional uncertainties was larger than 5mm in patients with greater fat thickness due to the baseline drift. The magnitude of the intrafractional motion was not uniform according to the direction, patients' physical characteristics, or tumour cavity location due to the baseline drift. Therefore, the intrafractional systematic movement should be properly managed. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The 1998 Australian external beam radiotherapy survey and IAEA/WHO TLD postal dose quality audit.

    PubMed

    Huntley, R; Izewska, J

    2000-03-01

    The results of an updated Australian survey of external beam radiotherapy centres are presented. Most of the centres provided most of the requested information. The relative caseloads of various linear accelerator photon and electron beams have not changed significantly since the previous survey in 1995. The mean age of Australian LINACs is 7.1 years and that of other radiotherapy machines is 14.7 years. Every Australian radiotherapy centre participated in a special run of the IAEA/WHO TLD postal dose quality audit program, which was provided for Australian centres by the IAEA and WHO in May 1998. The dose quoted by the centres was in nearly every case within 1.5% of the dose assessed by the IAEA. This is within the combined standard uncertainty of the IAEA TLD service (1.8%). The results confirm the accuracy and precision of radiotherapy dosimetry in Australia and the adequate dissemination of the Australian standards from ARL (now ARPANSA) to the centres. The Australian standards have recently been shown to agree with those of other countries to within 0.25% by comparison with the BIPM.

  18. A feasibility study of [sup 252]Cf neutron brachytherapy, cisplatin + 5-FU chemo-adjuvant and accelerated hyperfractionated radiotherapy for advanced cervical cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murayama, Y.; Wierzbicki, J.; Bowen, M.G.

    The purpose was to evaluate the feasibility and toxicity of [sup 252]Cf neutron brachytherapy combined with hyperaccelerated chemoradiotherapy for Stage III and IV cervical cancers. Eleven patients with advanced Stage IIIB-IVA cervical cancers were treated with [sup 252]Cf neutron brachytherapy in an up-front schedule followed by cisplatin (CDDP; 50 mg/m[sup 2]) chemotherapy and hyperfractionated accelerated (1.2 Gy bid) radiotherapy given concurrently with intravenous infusion of 5-Fluorouracil (5-FU) (1000 mg/m[sup 2]/day [times] 4 days) in weeks 1 and 4 with conventional radiation (weeks 2, 3, 5, and 6). Total dose at a paracervical point A isodose surface was 80-85 Gy-eq bymore » external and intracavitary therapy and 60 Gy at the pelvic sidewalls. Patients tolerated the protocol well. There was 91% compliance with the chemotherapy and full compliance with the [sup 252]Cf brachytherapy and the external beam radiotherapy. There were no problems with acute chemo or radiation toxicity. One patient developed a rectovaginal fistula (Grade 3-4 RTOG criteria) but no other patients developed significant late cystitis, proctitis or enteritis. There was complete response (CR) observed in all cases. With mean follow-up to 26 months, local control has been achieved with 90% actuarial 3-year survival with no evidence of disease (NED). [sup 252]Cf neutrons can be combined with cisplatin and 5-FU infusion chemotherapy plus hyperaccelerated chemoradiotherapy without unusual side effects or toxicity and with a high local response and tumor control rate. Further study of [sup 252]Cf neutron-chemoradiotherapy for advanced and bulky cervical cancer are indicated. The authors found chemotherapy was more effective with the improved local tumor control. 18 refs., 2 tabs.« less

  19. Hypofractionated Versus Standard Radiation Therapy With or Without Temozolomide for Older Glioblastoma Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arvold, Nils D.; Tanguturi, Shyam K.; Aizer, Ayal A.

    Purpose: Older patients with newly diagnosed glioblastoma have poor outcomes, and optimal treatment is controversial. Hypofractionated radiation therapy (HRT) is frequently used but has not been compared to patients receiving standard fractionated radiation therapy (SRT) and temozolomide (TMZ). Methods and Materials: We conducted a retrospective analysis of patients ≥65 years of age who received radiation for the treatment of newly diagnosed glioblastoma from 1994 to 2013. The distribution of clinical covariates across various radiation regimens was analyzed for possible selection bias. Survival was calculated using the Kaplan-Meier method. Comparison of hypofractionated radiation (typically, 40 Gy/15 fractions) versus standard fractionation (typically, 60 Gy/30 fractions)more » in the setting of temozolomide was conducted using Cox regression and propensity score analysis. Results: Patients received SRT + TMZ (n=57), SRT (n=35), HRT + TMZ (n=34), or HRT (n=9). Patients receiving HRT were significantly older (median: 79 vs 69 years of age; P<.001) and had worse baseline performance status (P<.001) than those receiving SRT. On multivariate analysis, older age (adjusted hazard ratio [AHR]: 1.06; 95% confidence interval [CI]: 1.01-1.10, P=.01), lower Karnofsky performance status (AHR: 1.02; 95% CI: 1.01-1.03; P=.01), multifocal disease (AHR: 2.11; 95% CI: 1.23-3.61, P=.007), and radiation alone (vs SRT + TMZ; SRT: AHR: 1.72; 95% CI: 1.06-2.79; P=.03; HRT: AHR: 3.92; 95% CI: 1.44-10.60, P=.007) were associated with decreased overall survival. After propensity score adjustment, patients receiving HRT with TMZ had similar overall survival compared with those receiving SRT with TMZ (AHR: 1.10, 95% CI: 0.50-2.4, P=.82). Conclusions: With no randomized data demonstrating equivalence between HRT and SRT in the setting of TMZ for glioblastoma, significant selection bias exists in the implementation of HRT. Controlling for this bias, we observed similar

  20. Health-Related Quality of Life After Single-Fraction High-Dose-Rate Brachytherapy and Hypofractionated External Beam Radiotherapy for Prostate Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morton, Gerard C., E-mail: gerard.morton@sunnybrook.ca; Loblaw, D. Andrew; Chung, Hans

    Purpose: To investigate the change in health-related quality of life for men after high-dose-rate brachytherapy and external beam radiotherapy for prostate cancer and the factors associated with this change. Methods and Materials: Eligible patients had clinically localized intermediate-risk prostate cancer. The patients received high-dose-rate brachytherapy as a single 15-Gy implant, followed by external beam radiotherapy to 37.5 Gy in 15 fractions. The patients were monitored prospectively for toxicity (Common Terminology Criteria for Adverse Events, version 3.0) and health-related quality of life (Expanded Prostate Cancer Index Composite [EPIC]). The proportion of patients developing a clinically significant difference in the EPIC domainmore » score (minimally important difference of >0.5 standard deviation) was determined and correlated with the baseline clinical and dosimetric factors. The study accrued 125 patients, with a median follow-up of 24 months. Results: By 24 months, 23% had Grade 2 urinary toxicity and only 5% had Grade 2 bowel toxicity, with no Grade 3 toxicity. The proportion of patients reporting a significant decrease in EPIC urinary, bowel, sexual, and hormonal domain scores was 53%, 51%, 45%, and 40% at 12 months and 57%, 65%, 51%, and 30% at 24 months, respectively. The proportion with a >1 standard deviation decrease in the EPIC urinary, bowel, sexual, and hormonal domain scores was 38%, 36%, 24%, and 20% at 12 months and 46%, 48%, 19%, and 8% at 24 months, respectively. On multivariate analysis, the dose to 10% of the urethra was associated with a decreasing EPIC urinary domain score (p = .0089) and, less strongly (p = .0312) with a decreasing hormonal domain score. No association was found between the prostate volume, bladder dose, or high-dose volume and urinary health-related quality of life. A high baseline International Index of Erectile Function score was associated (p = .0019) with a decreasing sexual domain score. The optimal

  1. R-IDEAL: A Framework for Systematic Clinical Evaluation of Technical Innovations in Radiation Oncology.

    PubMed

    Verkooijen, Helena M; Kerkmeijer, Linda G W; Fuller, Clifton D; Huddart, Robbert; Faivre-Finn, Corinne; Verheij, Marcel; Mook, Stella; Sahgal, Arjun; Hall, Emma; Schultz, Chris

    2017-01-01

    The pace of innovation in radiation oncology is high and the window of opportunity for evaluation narrow. Financial incentives, industry pressure, and patients' demand for high-tech treatments have led to widespread implementation of innovations before, or even without, robust evidence of improved outcomes has been generated. The standard phase I-IV framework for drug evaluation is not the most efficient and desirable framework for assessment of technological innovations. In order to provide a standard assessment methodology for clinical evaluation of innovations in radiotherapy, we adapted the surgical IDEAL framework to fit the radiation oncology setting. Like surgery, clinical evaluation of innovations in radiation oncology is complicated by continuous technical development, team and operator dependence, and differences in quality control. Contrary to surgery, radiotherapy innovations may be used in various ways, e.g., at different tumor sites and with different aims, such as radiation volume reduction and dose escalation. Also, the effect of radiation treatment can be modeled, allowing better prediction of potential benefits and improved patient selection. Key distinctive features of R-IDEAL include the important role of predicate and modeling studies (Stage 0), randomization at an early stage in the development of the technology, and long-term follow-up for late toxicity. We implemented R-IDEAL for clinical evaluation of a recent innovation in radiation oncology, the MRI-guided linear accelerator (MR-Linac). MR-Linac combines a radiotherapy linear accelerator with a 1.5-T MRI, aiming for improved targeting, dose escalation, and margin reduction, and is expected to increase the use of hypofractionation, improve tumor control, leading to higher cure rates and less toxicity. An international consortium, with participants from seven large cancer institutes from Europe and North America, has adopted the R-IDEAL framework to work toward coordinated, evidence

  2. Protocol for the isotoxic intensity modulated radiotherapy (IMRT) in stage III non-small cell lung cancer (NSCLC): a feasibility study.

    PubMed

    Haslett, Kate; Franks, Kevin; Hanna, Gerard G; Harden, Susan; Hatton, Matthew; Harrow, Stephen; McDonald, Fiona; Ashcroft, Linda; Falk, Sally; Groom, Nicki; Harris, Catherine; McCloskey, Paula; Whitehurst, Philip; Bayman, Neil; Faivre-Finn, Corinne

    2016-04-15

    The majority of stage III patients with non-small cell lung cancer (NSCLC) are unsuitable for concurrent chemoradiotherapy, the non-surgical gold standard of care. As the alternative treatment options of sequential chemoradiotherapy and radiotherapy alone are associated with high local failure rates, various intensification strategies have been employed. There is evidence to suggest that altered fractionation using hyperfractionation, acceleration, dose escalation, and individualisation may be of benefit. The MAASTRO group have pioneered the concept of 'isotoxic' radiotherapy allowing for individualised dose escalation using hyperfractionated accelerated radiotherapy based on predefined normal tissue constraints. This study aims to evaluate whether delivering isotoxic radiotherapy using intensity modulated radiotherapy (IMRT) is achievable. Isotoxic IMRT is a multicentre feasibility study. From June 2014, a total of 35 patients from 7 UK centres, with a proven histological or cytological diagnosis of inoperable NSCLC, unsuitable for concurrent chemoradiotherapy will be recruited. A minimum of 2 cycles of induction chemotherapy is mandated before starting isotoxic radiotherapy. The dose of radiation will be increased until one or more of the organs at risk tolerance or the maximum dose of 79.2 Gy is reached. The primary end point is feasibility, with accrual rates, local control and overall survival our secondary end points. Patients will be followed up for 5 years. The study has received ethical approval (REC reference: 13/NW/0480) from the National Research Ethics Service (NRES) Committee North West-Greater Manchester South. The trial is conducted in accordance with the Declaration of Helsinki and Good Clinical Practice (GCP). The trial results will be published in a peer-reviewed journal and presented internationally. NCT01836692; Pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

  3. Ultrashort courses of adjuvant breast radiotherapy: wave of the future or a fool's errand?

    PubMed

    Khan, Atif J; Dale, Roger G; Arthur, Douglas W; Haffty, Bruce G; Todor, Dorin A; Vicini, Frank A

    2012-04-15

    In accelerated partial breast irradiation (APBI), the most commonly used fractionation schemes include 340 or 385 centigrays delivered in a twice daily administration. A further progression of the APBI literature has been the recent interest in extremely short courses of adjuvant radiotherapy, usually delivered by intraoperative radiotherapy techniques. This newer area of single-fraction radiotherapy approaches remains highly contentious. In particular, the recently reported TARGIT trial has been the subject of both praise and scorn, and a critical examination of the trial data and the underlying hypotheses is warranted. Short-term outcomes of the related Italian ELIOT approach have also been reported. Although the assumptions of linear quadratic formalism are likely to hold true in the range of 2 to 8 grays, equating different schedules beyond this range is problematic. A major problem of current single-fraction approaches is that the treatment doses are chosen empirically, or are based on tolerability, or on the physical dose delivery characteristics of the chosen technology rather than radiobiological rationale. This review article summarizes the current data on ultrashort courses of adjuvant breast radiotherapy and highlights both the promise and the potential pitfalls of the abbreviated treatment. Copyright © 2011 American Cancer Society.

  4. Stereotactic Fractionated Radiotherapy in the Treatment of Juxtapapillary Choroidal Melanoma: The McGill University Experience

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Wassia, Rolina; Dal Pra, Alan; Shun, Kitty

    2011-11-15

    Purpose: To report our experience with linear accelerator-based stereotactic fractionated radiotherapy in the treatment of juxtapapillary choroidal melanoma. Methods and Materials: We performed a retrospective review of 50 consecutive patients diagnosed with juxtapapillary choroidal melanoma and treated with linear accelerator-based stereotactic fractionated radiotherapy between April 2003 and December 2009. Patients with small to medium sized lesions (Collaborative Ocular Melanoma Study classification) located within 2 mm of the optic disc were included. The prescribed radiation dose was 60 Gy in 10 fractions. The primary endpoints included local control, enucleation-free survival, and complication rates. Results: The median follow-up was 29 months (range,more » 1-77 months). There were 31 males and 29 females, with a median age of 69 years (range, 30-92 years). Eighty-four percent of the patients had medium sized lesions, and 16% of patients had small sized lesions. There were four cases of local progression (8%) and three enucleations (6%). Actuarial local control rates at 2 and 5 years were 93% and 86%, respectively. Actuarial enucleation-free survival rates at 2 and 5 years were 94% and 84%, respectively. Actuarial complication rates at 2 and 5 years were 33% and 88%, respectively, for radiation-induced retinopathy; 9.3% and 46.9%, respectively, for dry eye; 12% and 53%, respectively, for cataract; 30% and 90%, respectively, for visual loss [Snellen acuity (decimal equivalent), <0.1]; 11% and 54%, respectively, for optic neuropathy; and 18% and 38%, respectively, for neovascular glaucoma. Conclusions: Linear accelerator-based stereotactic fractionated radiotherapy using 60 Gy in 10 fractions is safe and has an acceptable toxicity profile. It has been shown to be an effective noninvasive treatment for juxtapapillary choroidal melanomas.« less

  5. Minimizing metastatic risk in radiotherapy fractionation schedules

    NASA Astrophysics Data System (ADS)

    Badri, Hamidreza; Ramakrishnan, Jagdish; Leder, Kevin

    2015-11-01

    Metastasis is the process by which cells from a primary tumor disperse and form new tumors at distant anatomical locations. The treatment and prevention of metastatic cancer remains an extremely challenging problem. This work introduces a novel biologically motivated objective function to the radiation optimization community that takes into account metastatic risk instead of the status of the primary tumor. In this work, we consider the problem of developing fractionated irradiation schedules that minimize production of metastatic cancer cells while keeping normal tissue damage below an acceptable level. A dynamic programming framework is utilized to determine the optimal fractionation scheme. We evaluated our approach on a breast cancer case using the heart and the lung as organs-at-risk (OAR). For small tumor α /β values, hypo-fractionated schedules were optimal, which is consistent with standard models. However, for relatively larger α /β values, we found the type of schedule depended on various parameters such as the time when metastatic risk was evaluated, the α /β values of the OARs, and the normal tissue sparing factors. Interestingly, in contrast to standard models, hypo-fractionated and semi-hypo-fractionated schedules (large initial doses with doses tapering off with time) were suggested even with large tumor α/β values. Numerical results indicate the potential for significant reduction in metastatic risk.

  6. Radiotherapy equipment and departments in the European countries: final results from the ESTRO-HERO survey.

    PubMed

    Grau, Cai; Defourny, Noémie; Malicki, Julian; Dunscombe, Peter; Borras, Josep M; Coffey, Mary; Slotman, Ben; Bogusz, Marta; Gasparotto, Chiara; Lievens, Yolande; Kokobobo, Arianit; Sedlmayer, Felix; Slobina, Elena; Feyen, Karen; Hadjieva, Tatiana; Odrazka, Karel; Grau Eriksen, Jesper; Jaal, Jana; Bly, Ritva; Chauvet, Bruno; Willich, Normann; Polgar, Csaba; Johannsson, Jakob; Cunningham, Moya; Magrini, Stefano; Atkocius, Vydmantas; Untereiner, Michel; Pirotta, Martin; Karadjinovic, Vanja; Levernes, Sverre; Sladowski, Krystol; Lurdes Trigo, Maria; Šegedin, Barbara; Rodriguez, Aurora; Lagerlund, Magnus; Pastoors, Bert; Hoskin, Peter; Vaarkamp, Jaap; Cleries Soler, Ramon

    2014-08-01

    Documenting the distribution of radiotherapy departments and the availability of radiotherapy equipment in the European countries is an important part of HERO - the ESTRO Health Economics in Radiation Oncology project. HERO has the overall aim to develop a knowledge base of the provision of radiotherapy in Europe and build a model for health economic evaluation of radiation treatments at the European level. The aim of the current report is to describe the distribution of radiotherapy equipment in European countries. An 84-item questionnaire was sent out to European countries, principally through their national societies. The current report includes a detailed analysis of radiotherapy departments and equipment (questionnaire items 26-29), analyzed in relation to the annual number of treatment courses and the socio-economic status of the countries. The analysis is based on validated responses from 28 of the 40 European countries defined by the European Cancer Observatory (ECO). A large variation between countries was found for most parameters studied. There were 2192 linear accelerators, 96 dedicated stereotactic machines, and 77 cobalt machines reported in the 27 countries where this information was available. A total of 12 countries had at least one cobalt machine in use. There was a median of 0.5 simulator per MV unit (range 0.3-1.5) and 1.4 (range 0.4-4.4) simulators per department. Of the 874 simulators, a total of 654 (75%) were capable of 3D imaging (CT-scanner or CBCT-option). The number of MV machines (cobalt, linear accelerators, and dedicated stereotactic machines) per million inhabitants ranged from 1.4 to 9.5 (median 5.3) and the average number of MV machines per department from 0.9 to 8.2 (median 2.6). The average number of treatment courses per year per MV machine varied from 262 to 1061 (median 419). While 69% of MV units were capable of IMRT only 49% were equipped for image guidance (IGRT). There was a clear relation between socio-economic status, as

  7. Conversion coefficients for determination of dispersed photon dose during radiotherapy: NRUrad input code for MCNP.

    PubMed

    Shahmohammadi Beni, Mehrdad; Ng, C Y P; Krstic, D; Nikezic, D; Yu, K N

    2017-01-01

    Radiotherapy is a common cancer treatment module, where a certain amount of dose will be delivered to the targeted organ. This is achieved usually by photons generated by linear accelerator units. However, radiation scattering within the patient's body and the surrounding environment will lead to dose dispersion to healthy tissues which are not targets of the primary radiation. Determination of the dispersed dose would be important for assessing the risk and biological consequences in different organs or tissues. In the present work, the concept of conversion coefficient (F) of the dispersed dose was developed, in which F = (Dd/Dt), where Dd was the dispersed dose in a non-targeted tissue and Dt is the absorbed dose in the targeted tissue. To quantify Dd and Dt, a comprehensive model was developed using the Monte Carlo N-Particle (MCNP) package to simulate the linear accelerator head, the human phantom, the treatment couch and the radiotherapy treatment room. The present work also demonstrated the feasibility and power of parallel computing through the use of the Message Passing Interface (MPI) version of MCNP5.

  8. Conversion coefficients for determination of dispersed photon dose during radiotherapy: NRUrad input code for MCNP

    PubMed Central

    Krstic, D.; Nikezic, D.

    2017-01-01

    Radiotherapy is a common cancer treatment module, where a certain amount of dose will be delivered to the targeted organ. This is achieved usually by photons generated by linear accelerator units. However, radiation scattering within the patient’s body and the surrounding environment will lead to dose dispersion to healthy tissues which are not targets of the primary radiation. Determination of the dispersed dose would be important for assessing the risk and biological consequences in different organs or tissues. In the present work, the concept of conversion coefficient (F) of the dispersed dose was developed, in which F = (Dd/Dt), where Dd was the dispersed dose in a non-targeted tissue and Dt is the absorbed dose in the targeted tissue. To quantify Dd and Dt, a comprehensive model was developed using the Monte Carlo N-Particle (MCNP) package to simulate the linear accelerator head, the human phantom, the treatment couch and the radiotherapy treatment room. The present work also demonstrated the feasibility and power of parallel computing through the use of the Message Passing Interface (MPI) version of MCNP5. PMID:28362837

  9. Organ doses can be estimated from the computed tomography (CT) dose index for cone-beam CT on radiotherapy equipment.

    PubMed

    Martin, Colin J; Abuhaimed, Abdullah; Sankaralingam, Marimuthu; Metwaly, Mohamed; Gentle, David J

    2016-06-01

    Cone beam computed tomography (CBCT) systems are fitted to radiotherapy linear accelerators and used for patient positioning prior to treatment by image guided radiotherapy (IGRT). Radiotherapists' and radiographers' knowledge of doses to organs from CBCT imaging is limited. The weighted CT dose index for a reference beam of width 20 mm (CTDIw,ref) is displayed on Varian CBCT imaging equipment known as an On-Board Imager (OBI) linked to the Truebeam linear accelerator. This has the potential to provide an indication of organ doses. This knowledge would be helpful for guidance of radiotherapy clinicians preparing treatments. Monte Carlo simulations of imaging protocols for head, thorax and pelvic scans have been performed using EGSnrc/BEAMnrc, EGSnrc/DOSXYZnrc, and ICRP reference computational male and female phantoms to derive the mean absorbed doses to organs and tissues, which have been compared with values for the CTDIw,ref displayed on the CBCT scanner console. Substantial variations in dose were observed between male and female phantoms. Nevertheless, the CTDIw,ref gave doses within  ±21% for the stomach and liver in thorax scans and 2  ×  CTDIw,ref can be used as a measure of doses to breast, lung and oesophagus. The CTDIw,ref could provide indications of doses to the brain for head scans, and the colon for pelvic scans. It is proposed that knowledge of the link between CTDIw for CBCT should be promoted and included in the training of radiotherapy staff.

  10. Enraged about radiotherapy.

    PubMed Central

    Sikora, K.

    1994-01-01

    The use of radiotherapy in treating breast cancer has meant that many women are able to avoid mastectomy, which is both physically and psychologically damaging. The side effects of radiotherapy, however, are given little attention. Many women have developed brachial plexus injury after radiotherapy for breast cancer, often resulting in severe pain and loss of use of the arm. There is no effective treatment for this injury and little help can be offered. In addition, many of the women did not require radiotherapy of nodal areas. A pressure group has been formed to support these women, to establish the right to compensation, and to ensure that radiotherapy regimens given to future patients will not damage the brachial plexus. Images p188-a PMID:8312773

  11. [Heavy charged particles radiotherapy--mainly carbon ion beams].

    PubMed

    Yanagi, Takeshi; Tsuji, Hiroshi; Tsujii, Hirohiko

    2003-12-01

    Carbon ion beams have superior dose distribution allowing selective irradiation to the tumor while minimizing irradiation to the surrounding normal tissues. Furthermore, carbon ions produce an increased density of local energy deposition with high-energy transfer (LET) components, resulting in radiobiological advantages. Stimulated by the favorable results in fast neutrons, helium ions, and neon ions, a clinical trial of carbon ion therapy was begun at the National Institute of Radiological Sciences in 1994. Carbon ions were generated by a medically dedicated accelerator (HIMAC, Heavy Ion Medical Accelerator in Chiba, Japan), which was the world's first heavy ion accelerator complex dedicated to medical use in a hospital environment. In general, patients were selected for treatment when their tumors could not be expected to respond favorably to conventional forms of therapy. A total of 1601 patients were registered in this clinical trial so far. The normal tissue reactions were acceptable, and there were no carbon related deaths. Carbon ion radiotherapy seemed to be a clinically feasible curative treatment modality, and appears to offer improved results not only over conventional X-rays but also even over surgery in some selected carcinomas.

  12. Radiotherapy dosimetry audit: three decades of improving standards and accuracy in UK clinical practice and trials.

    PubMed

    Clark, Catharine H; Aird, Edwin G A; Bolton, Steve; Miles, Elizabeth A; Nisbet, Andrew; Snaith, Julia A D; Thomas, Russell A S; Venables, Karen; Thwaites, David I

    2015-01-01

    Dosimetry audit plays an important role in the development and safety of radiotherapy. National and large scale audits are able to set, maintain and improve standards, as well as having the potential to identify issues which may cause harm to patients. They can support implementation of complex techniques and can facilitate awareness and understanding of any issues which may exist by benchmarking centres with similar equipment. This review examines the development of dosimetry audit in the UK over the past 30 years, including the involvement of the UK in international audits. A summary of audit results is given, with an overview of methodologies employed and lessons learnt. Recent and forthcoming more complex audits are considered, with a focus on future needs including the arrival of proton therapy in the UK and other advanced techniques such as four-dimensional radiotherapy delivery and verification, stereotactic radiotherapy and MR linear accelerators. The work of the main quality assurance and auditing bodies is discussed, including how they are working together to streamline audit and to ensure that all radiotherapy centres are involved. Undertaking regular external audit motivates centres to modernize and develop techniques and provides assurance, not only that radiotherapy is planned and delivered accurately but also that the patient dose delivered is as prescribed.

  13. Radiotherapy dosimetry audit: three decades of improving standards and accuracy in UK clinical practice and trials

    PubMed Central

    Aird, Edwin GA; Bolton, Steve; Miles, Elizabeth A; Nisbet, Andrew; Snaith, Julia AD; Thomas, Russell AS; Venables, Karen; Thwaites, David I

    2015-01-01

    Dosimetry audit plays an important role in the development and safety of radiotherapy. National and large scale audits are able to set, maintain and improve standards, as well as having the potential to identify issues which may cause harm to patients. They can support implementation of complex techniques and can facilitate awareness and understanding of any issues which may exist by benchmarking centres with similar equipment. This review examines the development of dosimetry audit in the UK over the past 30 years, including the involvement of the UK in international audits. A summary of audit results is given, with an overview of methodologies employed and lessons learnt. Recent and forthcoming more complex audits are considered, with a focus on future needs including the arrival of proton therapy in the UK and other advanced techniques such as four-dimensional radiotherapy delivery and verification, stereotactic radiotherapy and MR linear accelerators. The work of the main quality assurance and auditing bodies is discussed, including how they are working together to streamline audit and to ensure that all radiotherapy centres are involved. Undertaking regular external audit motivates centres to modernize and develop techniques and provides assurance, not only that radiotherapy is planned and delivered accurately but also that the patient dose delivered is as prescribed. PMID:26329469

  14. A Preliminary Design Of Application Of Wireless Identification And Sensing Platform On External Beam Radiotherapy

    NASA Astrophysics Data System (ADS)

    Heranudin; Bakhri, S.

    2018-02-01

    A linear accelerator (linac) is widely used as a means of radiotherapy by focusing high-energy photons in the targeted tumor of patient. Incorrectness of the shooting can lead normal tissue surrounding the tumor received unnecessary radiation and become damaged cells. A method is required to minimize the incorrectness that mostly caused by movement of the patient during radiotherapy process. In this paper, the Wireless Identification and Sensing Platform (WISP) architecture was employed to monitor in real time the movement of the patient’s body during radiotherapy process. In general, the WISP is a wearable sensors device that can transmit measurement data wirelessly. In this design, the measurement devices consist of an accelerometer, a barometer and an ionizing radiation sensor. If any changes in the body position which resulted in incorrectness of the shooting, the accelerometer and the barometer will trigger a warning to the linac operator. In addition, the radiation sensor in the WISP will detect unwanted radiation and that can endanger the patient. A wireless feature in this device can ease in implementation. Initial analyses have been performed and showed that the WISP is feasible to be applied on external beam radiotherapy.

  15. Extracranial Facial Nerve Schwannoma Treated by Hypo-fractionated CyberKnife Radiosurgery.

    PubMed

    Sasaki, Ayaka; Miyazaki, Shinichiro; Hori, Tomokatsu

    2016-09-21

    Facial nerve schwannoma is a rare intracranial tumor. Treatment for this benign tumor has been controversial. Here, we report a case of extracranial facial nerve schwannoma treated successfully by hypo-fractionated CyberKnife (Accuray, Sunnyvale, CA) radiosurgery and discuss the efficacy of this treatment. A 34-year-old female noticed a swelling in her right mastoid process. The lesion enlarged over a seven-month period, and she experienced facial spasm on the right side. She was diagnosed with a facial schwannoma via a magnetic resonance imaging (MRI) scan of the head and neck and was told to wait until the facial nerve palsy subsides. She was referred to our hospital for radiation therapy. We planned a fractionated CyberKnife radiosurgery for three consecutive days. After CyberKnife radiosurgery, the mass in the right parotid gradually decreased in size, and the facial nerve palsy disappeared. At her eight-month follow-up, her facial spasm had completely disappeared. There has been no recurrence and the facial nerve function has been normal. We successfully demonstrated the efficacy of CyberKnife radiosurgery as an alternative treatment that also preserves neurofunction for facial nerve schwannomas.

  16. WE-F-304-05: Cranial TCP/NTCP Modeling Insights and Caveats

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    El Naqa, I.

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe andmore » effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear

  17. WE-F-304-04: Radiosurgery for Vestibular Schwannomas: Tumor Control Probability Analyses and Recommended Reporting Standards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Soltys, S.

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe andmore » effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear

  18. WE-F-304-02: Recurrent HNC Treated with SBRT: TCP-Based Outcome Estimates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clump, D.

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe andmore » effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear

  19. WE-F-304-01: Overview of the Working Group On Stereotactic Body Radiation Therapy (WGSBRT)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yorke, E.

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe andmore » effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear

  20. Experimental results and model calculations of excitation functions relevant to the production of specific radioisotopes for metabolic radiotherapy and for pet

    NASA Astrophysics Data System (ADS)

    Menapace, E.; Birattari, C.; Bonardi, M. L.; Groppi, F.

    2004-10-01

    First results are given from the comparison of experimental values and model calculations on accelerator-produced high specific activity radionuclides in no-carrier-added (NCA) form. The relevant radioisotopes are: 64Cu, produced by natZn(d, αxn) and natZn(d,2p) reactions, for simultaneous positron/negatron metabolic radiotherapy and PET imaging; 66Ga high-energy positron emitter (4.2 MeV), produced by natZn(d, xn) reactions, for metabolic radiotherapy and for PET; 186gRe, produced by 186W(p,n) and 186W(d,2n) reactions, for negatron (1.1 MeV) metabolic radiotherapy; 211At/ 211Po, produced by 209Bi( α,2n) reaction (with spike of gamma emitter 210At produced by 209Bi( α,3n) reaction) and 225Ac/ 213Bi/ 213Po, produced by 226Ra(p,2n) reaction, both for high-LET radiotherapy.

  1. Dedicated magnetic resonance imaging in the radiotherapy clinic.

    PubMed

    Karlsson, Mikael; Karlsson, Magnus G; Nyholm, Tufve; Amies, Christopher; Zackrisson, Björn

    2009-06-01

    To introduce a novel technology arrangement in an integrated environment and outline the logistics model needed to incorporate dedicated magnetic resonance (MR) imaging in the radiotherapy workflow. An initial attempt was made to analyze the value and feasibility of MR-only imaging compared to computed tomography (CT) imaging, testing the assumption that MR is a better choice for target and healthy tissue delineation in radiotherapy. A 1.5-T MR unit with a 70-cm-bore size was installed close to a linear accelerator, and a special trolley was developed for transporting patients who were fixated in advance between the MR unit and the accelerator. New MR-based workflow procedures were developed and evaluated. MR-only treatment planning has been facilitated, thus avoiding all registration errors between CT and MR scans, but several new aspects of MR imaging must be considered. Electron density information must be obtained by other methods. Generation of digitally reconstructed radiographs (DRR) for x-ray setup verification is not straight forward, and reliable corrections of geometrical distortions must be applied. The feasibility of MR imaging virtual simulation has been demonstrated, but a key challenge to overcome is correct determination of the skeleton, which is often needed for the traditional approach of beam modeling. The trolley solution allows for a highly precise setup for soft tissue tumors without the invasive handling of radiopaque markers. The new logistics model with an integrated MR unit is efficient and will allow for improved tumor definition and geometrical precision without a significant loss of dosimetric accuracy. The most significant development needed is improved bone imaging.

  2. [Single-dose palliative radiotherapy in inoperable non-small-cell lung carcinoma].

    PubMed

    Scolaro, T; Bacigalupo, A; Giudici, S; Guenzi, M; Vitale, V

    1995-12-01

    The treatment of choice for advanced inoperable non-small cell lung cancer (NSCLC) is radiation therapy. Palliative radiotherapy schedules vary considerably in different centers, but a 30-Gy dose given in ten fractions over two weeks is a typical standard schedule. Our study was aimed at investigating whether a shorter course of only one 10-Gy fraction allows good palliation in the treatment of inoperable NSCLC patients whose main symptoms are related to an intrathoracic lesion. Patients of both sexes and any age, untreated with radiotherapy, with inoperable and histologically or cytologically proved NSCLC were examined. Seventeen patients, too advanced for radical "curative" radiotherapy and whose main symptoms were related to primary intrathoracic lesions, entered the study even though they had metastases. On admission, 76% (13/17) of patients had cough 76% (13/17) dyspnea, 70.7% (12/17) chest pain and 23.6% (4/17) hemoptysis. They received a single dose of 10 Gy, delivered with an 18-Mv linear accelerator via anteroposteriorly opposing portals without spinal cord shielding. Treatment volume usually included the macroscopically detected lesion identified with a CT simulator. Palliation of symptoms was achieved in high rates of patients: 46% for cough, 69% for dyspnea, 83% for pain and 75% for hemoptysis. These results were obtained within one month of treatment. Unfortunately, palliation of symptoms did not last long, decreasing to 42% within two months of the end of treatment and to 32% at three months. Four patients were retreated, one patient three months and three patients two months after the end of radiotherapy. Ten Gy to the target volume were administered as retreatment with spinal cord shielding. Side-effects were mild: nausea in 3 patients (17%), vomiting in one patient (5%) and grade-II dysphagia in two patients were observed and classified according to WHO criteria. Pain increased 24 hours after radiotherapy in five patients. We can conclude that

  3. A Pilot Study of Hypofractionated Stereotactic Radiation Therapy and Sunitinib in Previously Irradiated Patients With Recurrent High-Grade Glioma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wuthrick, Evan J., E-mail: evan.wuthrick@osumc.edu; Curran, Walter J.; Camphausen, Kevin

    Purpose/Objective(s): Angiogenic blockade with irradiation may enhance the therapeutic ratio of radiation therapy (RT) through vascular normalization. We sought to determine the safety and toxicity profile of continuous daily-dosed sunitinib when combined with hypofractionated stereotactic RT (fSRT) for recurrent high-grade gliomas (rHGG). Methods and Materials: Eligible patients had malignant high-grade glioma that recurred or progressed after primary surgery and RT. All patients received a minimum of a 10-day course of fSRT, had World Health Organization performance status of 0 to 1, and a life expectancy of >3 months. During fSRT, sunitinib was administered at 37.5 mg daily. The primary endpoint was acutemore » toxicity, and response was assessed via serial magnetic resonance imaging. Results: Eleven patients with rHGG were enrolled. The fSRT doses delivered ranged from 30 to 42 Gy in 2.5- to 3.75-Gy fractions. The median follow-up time was 40 months. Common acute toxicities included hematologic disorders, fatigue, hypertension, and elevated liver transaminases. Sunitinib and fSRT were well tolerated. One grade 4 mucositis toxicity occurred, and no grade 4 or 5 hypertensive events or intracerebral hemorrhages occurred. One patient had a nearly complete response, and 4 patients had stable disease for >9 months. Two patients (18%) remain alive and progression-free >3 years from enrollment. The 6-month progression-free survival was 45%. Conclusions: Sunitinib at a daily dose of 37.5 mg given concurrently with hypofractionated stereotactic reirradiation for rHGG yields acceptable toxicities and an encouraging 6-month progression-free survival.« less

  4. Hypothyroidism in patients treated with radiotherapy for head and neck carcinoma: standardised long-term follow-up study.

    PubMed

    Alba, J R; Basterra, J; Ferrer, J C; Santonja, F; Zapater, E

    2016-05-01

    Hypothyroidism is a common complication when radiotherapy is part of the treatment for head and neck tumours. This study aimed to show the incidence of hypothyroidism and possible risk factors in these patients. Factors related to the population, tumour, treatment and occurrence of hypothyroidism were analysed in 241 patients diagnosed with head and neck carcinoma. Approximately 53 per cent of patients were diagnosed with radiation-induced hypothyroidism. Its occurrence was related to: tumour location, laryngeal surgery type, neck dissection type, post-operative complications, cervical radiotherapy and radiotherapy unit type (linear particle accelerator or telecobalt therapy technology). Control of thyroid function should be standardised for several years after treatment, particularly in patients with risk factors, such as those treated with telecobalt therapy, those with post-operative complications and for whom the thyroid parenchyma is included in the irradiated area (laryngeal or pharyngeal location and bilateral cervical radiation).

  5. Mild Lung Restriction in Breast Cancer Patients After Hypofractionated and Conventional Radiation Therapy: A 3-Year Follow-Up

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Verbanck, Sylvia, E-mail: sylvia.verbanck@uzbrussel.be; Hanon, Shane; Schuermans, Daniel

    Purpose: To assess the effect of radiation therapy on lung function over the course of 3 years. Methods and Materials: Evolution of restrictive and obstructive lung function parameters was investigated in 108 breast cancer participants in a randomized, controlled trial comparing conventional radiation therapy (CR) and hypofractionated tomotherapy (TT) (age at inclusion ranging 32-81 years). Spirometry, plethysmography, and hemoglobin-corrected diffusing capacity were assessed at baseline and after 3 months and 1, 2, and 3 years. Natural aging was accounted for by considering all lung function parameters in terms of percent predicted values using the most recent reference values for women aged up to 80 years. Results:more » In the patients with negligible history of respiratory disease or smoking (n=77), the greatest rate of functional decline was observed during the initial 3 months, this acute decrease being more marked in the CR versus the TT arm. During the remainder of the 3-year follow-up period, values (in terms of percent predicted) were maintained (diffusing capacity) or continued to decline at a slower rate (forced vital capacity). However, the average decline of the restrictive lung function parameters over a 3-year period did not exceed 9% predicted in either the TT or the CR arm. Obstructive lung function parameters remained unaffected throughout. Including also the 31 patients with a history of respiratory disease or more than 10 pack-years showed a very similar restrictive pattern. Conclusions: In women with breast cancer, both conventional radiation therapy and hypofractionated tomotherapy induce small but consistent restrictive lung patterns over the course of a 3-year period, irrespective of baseline respiratory status or smoking history. The fastest rate of lung function decline generally occurred in the first 3 months.« less

  6. Out-of-field neutron and leakage photon exposures and the associated risk of second cancers in high-energy photon radiotherapy: current status.

    PubMed

    Takam, R; Bezak, E; Marcu, L G; Yeoh, E

    2011-10-01

    Determination and understanding of out-of-field neutron and photon doses in accelerator-based radiotherapy is an important issue since linear accelerators operating at high energies (>10 MV) produce secondary radiations that irradiate parts of the patient's anatomy distal to the target region, potentially resulting in detrimental health effects. This paper provides a compilation of data (technical and clinical) reported in the literature on the measurement and Monte Carlo simulations of peripheral neutron and photon doses produced from high-energy medical linear accelerators and the reported risk and/or incidence of second primary cancer of tissues distal to the target volume. Information in the tables facilitates easier identification of (1) the various methods and measurement techniques used to determine the out-of-field neutron and photon radiations, (2) reported linac-dependent out-of-field doses, and (3) the risk/incidence of second cancers after radiotherapy due to classic and modern treatment methods. Regardless of the measurement technique and type of accelerator, the neutron dose equivalent per unit photon dose ranges from as low as 0.1 mSv/Gy to as high as 20.4 mSv/Gy. This radiation dose potentially contributes to the induction of second primary cancer in normal tissues outside the treated area.

  7. Impact of Adding Concomitant Chemotherapy to Hyperfractionated Accelerated Radiotherapy for Advanced Head-and-Neck Squamous Cell Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nuyts, Sandra; Dirix, Piet; Clement, Paul M.J.

    2009-03-15

    Purpose: To evaluate the feasibility and efficacy of a hyperfractionated accelerated radiotherapy (RT) schedule combined with concomitant chemotherapy (Cx) in patients with locally advanced head-and-neck squamous cell carcinoma. Methods and Materials: Between 2004 and 2007, a total of 90 patients with locoregionally advanced head-and-neck squamous cell carcinoma underwent irradiation according to a hybrid fractionation schedule consisting of 20 fractions of 2 Gy (once daily) followed by 20 fractions of 1.6 Gy (twice daily) to a total dose of 72 Gy. Concomitant Cx (cisplatinum 100 mg/m{sup 2}) was administered at the start of Weeks 1 and 4. Treatment outcome and toxicitymore » were retrospectively compared with a previous patient group (n = 73) treated with the same schedule, but without concomitant Cx, between 2001 and 2004. Results: The locoregional control (LRC) rate was 70% after 2 years. Two-year overall and 2-year disease-free survival rates were 74% and 60%, respectively. In comparison with the RT-only group, an improvement of 15% in both LRC (p = 0.03) and overall survival (p = 0.09) was observed. All patients were treated to full radiation dose according to protocol, although the Cx schedule had to be adjusted in 12 patients. No acute Grade 4 or 5 toxicity was seen, but incidences of Grade 3 acute mucositis (74.5% vs. 50.7%; p = 0.002) and dysphagia (82.2% vs. 47.9%; p < 0.001) were significantly higher in the chemoradiotherapy group compared with patients treated with RT alone. Conclusion: With this chemoradiotherapy regimen, excellent LRC and survival rates were achieved, with acceptable acute toxicity.« less

  8. Accelerated partial breast irradiation with external beam radiotherapy : First results of the German phase 2 trial.

    PubMed

    Ott, Oliver J; Strnad, Vratislav; Stillkrieg, Wilhelm; Uter, Wolfgang; Beckmann, Matthias W; Fietkau, Rainer

    2017-01-01

    To evaluate the feasibility and efficacy of external beam three-dimensional (3D) conformal accelerated partial breast irradiation (APBI) for selected patients with early breast cancer. Between 2011 and 2016, 72 patients were recruited for this prospective phase 2 trial. Patients were eligible for APBI if they had histologically confirmed breast cancer or pure ductal carcinoma in situ (DCIS), a tumor diameter ≤3 cm, clear resection margins ≥2 mm, no axillary lymph node involvement, no distant metastases, tumor bed clips, and were aged ≥50 years. Patients were excluded if mammography showed a multicentric invasive growth pattern, or if they had residual diffuse microcalcifications postoperatively, an extensive intraductal component, or vessel invasion. Patients received 3D conformal external beam APBI with a total dose of 38 Gy in 10 fractions in 1-2 weeks. The trial had been registered at the German Clinical Trials Register, DRKS-ID: DRKS00004417. Median follow-up was 25.5 months (range 1-61 months). Local control was maintained in 71 of 72 patients. The 3‑year local recurrence rate was 2.1% (95% confidence interval, CI: 0-6.1%). Early toxicity (grade 1 radiodermatitis) was seen in 34.7% (25/72). Late side effects ≥ grade 3 did not occur. Cosmetic results were rated as excellent/good in 96.7% (59/61). APBI with external beam radiotherapy techniques is feasible with low toxicity and, according to the results of the present and other studies, on the way to becoming a standard treatment option for a selected subgroup of patients.

  9. The first patient treatment of electromagnetic-guided real time adaptive radiotherapy using MLC tracking for lung SABR.

    PubMed

    Booth, Jeremy T; Caillet, Vincent; Hardcastle, Nicholas; O'Brien, Ricky; Szymura, Kathryn; Crasta, Charlene; Harris, Benjamin; Haddad, Carol; Eade, Thomas; Keall, Paul J

    2016-10-01

    Real time adaptive radiotherapy that enables smaller irradiated volumes may reduce pulmonary toxicity. We report on the first patient treatment of electromagnetic-guided real time adaptive radiotherapy delivered with MLC tracking for lung stereotactic ablative body radiotherapy. A clinical trial was developed to investigate the safety and feasibility of MLC tracking in lung. The first patient was an 80-year old man with a single left lower lobe lung metastasis to be treated with SABR to 48Gy in 4 fractions. In-house software was integrated with a standard linear accelerator to adapt the treatment beam shape and position based on electromagnetic transponders implanted in the lung. MLC tracking plans were compared against standard ITV-based treatment planning. MLC tracking plan delivery was reconstructed in the patient to confirm safe delivery. Real time adaptive radiotherapy delivered with MLC tracking compared to standard ITV-based planning reduced the PTV by 41% (18.7-11cm 3 ) and the mean lung dose by 30% (202-140cGy), V20 by 35% (2.6-1.5%) and V5 by 9% (8.9-8%). An emerging technology, MLC tracking, has been translated into the clinic and used to treat lung SABR patients for the first time. This milestone represents an important first step for clinical real-time adaptive radiotherapy that could reduce pulmonary toxicity in lung radiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Radiotherapy and chemotherapy change vessel tree geometry and metastatic spread in a small cell lung cancer xenograft mouse tumor model

    PubMed Central

    Bethge, Anja; Schumacher, Udo

    2017-01-01

    Background Tumor vasculature is critical for tumor growth, formation of distant metastases and efficiency of radio- and chemotherapy treatments. However, how the vasculature itself is affected during cancer treatment regarding to the metastatic behavior has not been thoroughly investigated. Therefore, the aim of this study was to analyze the influence of hypofractionated radiotherapy and cisplatin chemotherapy on vessel tree geometry and metastasis formation in a small cell lung cancer xenograft mouse tumor model to investigate the spread of malignant cells during different treatments modalities. Methods The biological data gained during these experiments were fed into our previously developed computer model “Cancer and Treatment Simulation Tool” (CaTSiT) to model the growth of the primary tumor, its metastatic deposit and also the influence on different therapies. Furthermore, we performed quantitative histology analyses to verify our predictions in xenograft mouse tumor model. Results According to the computer simulation the number of cells engrafting must vary considerably to explain the different weights of the primary tumor at the end of the experiment. Once a primary tumor is established, the fractal dimension of its vasculature correlates with the tumor size. Furthermore, the fractal dimension of the tumor vasculature changes during treatment, indicating that the therapy affects the blood vessels’ geometry. We corroborated these findings with a quantitative histological analysis showing that the blood vessel density is depleted during radiotherapy and cisplatin chemotherapy. The CaTSiT computer model reveals that chemotherapy influences the tumor’s therapeutic susceptibility and its metastatic spreading behavior. Conclusion Using a system biological approach in combination with xenograft models and computer simulations revealed that the usage of chemotherapy and radiation therapy determines the spreading behavior by changing the blood vessel geometry

  11. Patterns of radiotherapy infrastructure in Japan and in other countries with well-developed radiotherapy infrastructures.

    PubMed

    Nakamura, Katsumasa; Konishi, Kenta; Komatsu, Tetsuya; Sasaki, Tomonari; Shikama, Naoto

    2018-05-01

    In high-income countries, the number of radiotherapy machine per population reaches a sufficient level. However, the patterns of infrastructure of radiotherapy in high-income countries are not well known. Among 29 high-income countries with gross national income of $25,000 or more per capita, we selected 23 countries whose total number of newly diagnosed cancer patients in 2012 was reported in the Organisation for Economic Co-operation and Development Health Statistics 2017. The numbers of radiotherapy centers and teletherapy machines in each of these 23 countries were collected using the Dictionary of Radiotherapy Centers database. The number of cancer patients per teletherapy machine was 452.35-1398.22 (median 711.66) with a three-fold variation, whereas the number of cancer patients per radiotherapy center varied even more widely, from 826.16 to 5159.86 (median 2259.83) with a six-fold variation. The average number of teletherapy machines per radiotherapy center also ranged widely, from 1.24 to 8.29 (median 3.11) with a seven-fold variation. The number of teletherapy machines in each country was almost proportional to that of cancer patients, and the number of teletherapy machines per radiotherapy center was inversely related to the number of radiotherapy centers per cancer patients. The number of teletherapy machines per radiotherapy center in Japan was 1.24, the most fragmented among the high-income countries. The percentage of large radiotherapy centers having three or more teletherapy machines in Japan was the smallest among 23 high-income countries. Optimization of the radiotherapy infrastructure in Japan should be carefully considered.

  12. Development of C6+ laser ion source and RFQ linac for carbon ion radiotherapy

    NASA Astrophysics Data System (ADS)

    Sako, T.; Yamaguchi, A.; Sato, K.; Goto, A.; Iwai, T.; Nayuki, T.; Nemoto, K.; Kayama, T.; Takeuchi, T.

    2016-02-01

    A prototype C6+ injector using a laser ion source has been developed for a compact synchrotron dedicated to carbon ion radiotherapy. The injector consists of a laser ion source and a 4-vane radio-frequency quadrupole (RFQ) linac. Ion beams are extracted from plasma and directly injected into the RFQ. A solenoid guides the low-energy beams into the RFQ. The RFQ is designed to accelerate high-intensity pulsed beams. A structure of monolithic vanes and cavities is adopted to reduce its power consumption. In beam acceleration tests, a solenoidal magnetic field set between the laser ion source and the RFQ helped increase both the peak currents before and after the RFQ by a factor of 4.

  13. A Phase I Study of Chemoradiotherapy With Use of Involved-Field Conformal Radiotherapy and Accelerated Hyperfractionation for Stage III Non-Small Cell Lung Cancer: WJTOG 3305

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tada, Takuhito, E-mail: tada@msic.med.osaka-cu.ac.jp; Department of Radiology, Izumi Municipal Hospital, Izumi; Chiba, Yasutaka

    2012-05-01

    Purpose: A Phase I study to determine a recommended dose of thoracic radiotherapy using accelerated hyperfractionation for unresectable non-small-cell lung cancer was conducted. Methods and Materials: Patients with unresectable Stage III non-small-cell lung cancer were treated intravenously with carboplatin (area under the concentration curve 2) and paclitaxel (40 mg/m{sup 2}) on Days 1, 8, 15, and 22 with concurrent twice-daily thoracic radiotherapy (1.5 Gy per fraction) beginning on Day 1 followed by two cycles of consolidation chemotherapy using carboplatin (area under the concentration curve 5) and paclitaxel (200 mg/m{sup 2}). Total doses were 54 Gy in 36 fractions, 60 Gymore » in 40 fractions, 66 Gy in 44 fractions, and 72 Gy in 48 fractions at Levels 1 to 4. The dose-limiting toxicity, defined as Grade {>=}4 esophagitis and neutropenic fever and Grade {>=}3 other nonhematologic toxicities, was monitored for 90 days. Results: Of 26 patients enrolled, 22 patients were assessable for response and toxicity. When 4 patients entered Level 4, enrollment was closed to avoid severe late toxicities. Dose-limiting toxicities occurred in 3 patients. They were Grade 3 neuropathy at Level 1 and Level 3 and Grade 3 infection at Level 1. However, the maximum tolerated dose was not reached. The median survival time was 28.6 months for all patients. Conclusions: The maximum tolerated dose was not reached, although the dose of radiation was escalated to 72 Gy in 48 fractions. However, a dose of 66 Gy in 44 fractions was adopted for this study because late toxicity data were insufficient.« less

  14. GPU-accelerated automatic identification of robust beam setups for proton and carbon-ion radiotherapy

    NASA Astrophysics Data System (ADS)

    Ammazzalorso, F.; Bednarz, T.; Jelen, U.

    2014-03-01

    We demonstrate acceleration on graphic processing units (GPU) of automatic identification of robust particle therapy beam setups, minimizing negative dosimetric effects of Bragg peak displacement caused by treatment-time patient positioning errors. Our particle therapy research toolkit, RobuR, was extended with OpenCL support and used to implement calculation on GPU of the Port Homogeneity Index, a metric scoring irradiation port robustness through analysis of tissue density patterns prior to dose optimization and computation. Results were benchmarked against an independent native CPU implementation. Numerical results were in agreement between the GPU implementation and native CPU implementation. For 10 skull base cases, the GPU-accelerated implementation was employed to select beam setups for proton and carbon ion treatment plans, which proved to be dosimetrically robust, when recomputed in presence of various simulated positioning errors. From the point of view of performance, average running time on the GPU decreased by at least one order of magnitude compared to the CPU, rendering the GPU-accelerated analysis a feasible step in a clinical treatment planning interactive session. In conclusion, selection of robust particle therapy beam setups can be effectively accelerated on a GPU and become an unintrusive part of the particle therapy treatment planning workflow. Additionally, the speed gain opens new usage scenarios, like interactive analysis manipulation (e.g. constraining of some setup) and re-execution. Finally, through OpenCL portable parallelism, the new implementation is suitable also for CPU-only use, taking advantage of multiple cores, and can potentially exploit types of accelerators other than GPUs.

  15. Stereotactic radiotherapy following surgery for brain metastasis: Predictive factors for local control and radionecrosis.

    PubMed

    Doré, M; Martin, S; Delpon, G; Clément, K; Campion, L; Thillays, F

    2017-02-01

    To evaluate local control and adverse effects after postoperative hypofractionated stereotactic radiosurgery in patients with brain metastasis. We reviewed patients who had hypofractionated stereotactic radiosurgery (7.7Gy×3 prescribed to the 70% isodose line, with 2mm planning target volume margin) following resection from March 2008 to January 2014. The primary endpoint was local failure defined as recurrence within the surgical cavity. Secondary endpoints were distant failure rates and the occurrence of radionecrosis. Out of 95 patients, 39.2% had metastatic lesions from a non-small cell lung cancer primary tumour. The median Graded Prognostic Assessment score was 3 (48% of patients). One-year local control rates were 84%. Factors associated with improved local control were no cavity enhancement on pre-radiation MRI (P<0.00001), planning target volume less than 12cm 3 (P=0.005), Graded Prognostic Assessment score 2 or above (P=0.009). One-year distant cerebral control rates were 56%. Thirty-three percent of patients received whole brain radiation therapy. Histologically proven radionecrosis of brain tissue occurred in 7.2% of cases. The size of the preoperative lesion and the volume of healthy brain tissue receiving 21Gy (V 21 ) were both predictive of the incidence of radionecrosis (P=0.010 and 0.036, respectively). Adjuvant hypofractionated stereotactic radiosurgery to the postoperative cavity in patients with brain metastases results in excellent local control in selected patients, helps delay the use of whole brain radiation, and is associated with a relatively low risk of radionecrosis. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  16. TU-G-BRA-01: Assessing Radiation-Induced Reductions in Regional Lung Perfusion Following Stereotactic Radiotherapy for Lung Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McGurk, R; Green, R; Lawrence, M

    2015-06-15

    Purpose: The dose-dependent nature of radiation therapy (RT)-induced lung injury following hypo-fractionated stereotactic RT is unclear. We herein report preliminary results of a prospective study assessing the magnitude of RT-induced reductions in regional lung perfusion following hypo-fractionated stereotactic RT. Methods: Four patients undergoing hypo-fractionated stereotactic lung RT (SBRT: 12 Gy x 4 fractions or 10 Gy x 5 fractions) had a pre-treatment SPECT (single-photon emission computed tomography) perfusion scan providing a 3D map of regional lung perfusion. Scans were repeated 3–6 months post-treatment. Pre- and post SPECT scans were registered to the planning CT scan (and hence the 3D dosemore » data). Changes in regional perfusion (counts per cc on the pre-post scans) were computed in regions of the lung exposed to different doses of radiation (in 5 Gy intervals), thus defining a dose-response function. SPECT scans were internally normalized to the regions receiving <5 Gy. Results: At 3 months post-RT, the changes in perfusion are highly variable. At 6 months, there is a consistent dose-dependent reduction in regional perfusion. The average percent decline in regional perfusion was 10% at 15–20 Gy, 20% at 20–25 Gy, and 30% at 25–30 Gy representing a relatively linear dose response with an approximate 2% reduction per Gray for doses in excess of 10 Gy. There was a subtle increase in perfusion in the lung receiving <10 Gy. Conclusion: Hypo-fractionated stereotactic RT appears to cause a dose-dependent reduction in regional lung perfusion. There appears to be a threshold effect with no apparent perfusion loss at doses <10 Gy, though this might be in part due to the normalization technique used. Additional data is needed from a larger number of patients to better assess this issue. This sort of data can be used to assist optimizing RT treatment plans that minimize the risk of lung injury. Partly supported by the NIH (CA69579) and the Lance

  17. [Image-guided radiotherapy and partial delegation to radiotherapy technicians: Clermont-Ferrand experience].

    PubMed

    Loos, G; Moreau, J; Miroir, J; Benhaïm, C; Biau, J; Caillé, C; Bellière, A; Lapeyre, M

    2013-10-01

    The various image-guided radiotherapy techniques raise the question of how to achieve the control of patient positioning before irradiation session and sharing of tasks between radiation oncologists and radiotherapy technicians. We have put in place procedures and operating methods to make a partial delegation of tasks to radiotherapy technicians and secure the process in three situations: control by orthogonal kV imaging (kV-kV) of bony landmarks, control by kV-kV imaging of intraprostatic fiducial goldmarkers and control by cone beam CT (CBCT) imaging for prostate cancer. Significant medical overtime is required to control these three IGRT techniques. Because of their competence in imaging, these daily controls can be delegated to radiotherapy technicians. However, to secure the process, initial training and regular evaluation are essential. The analysis of the comparison of the use of kV/kV on bone structures allowed us to achieve a partial delegation of control to radiotherapy technicians. Controlling the positioning of the prostate through the use and automatic registration of fiducial goldmarkers allows better tracking of the prostate and can be easily delegated to radiotherapy technicians. The analysis of the use of daily cone beam CT for patients treated with intensity modulated irradiation is underway, and a comparison of practices between radiotherapy technicians and radiation oncologists is ongoing to know if a partial delegation of this control is possible. Copyright © 2013. Published by Elsevier SAS.

  18. Demand for radiotherapy in Spain.

    PubMed

    Rodríguez, A; Borrás, J M; López-Torrecilla, J; Algara, M; Palacios-Eito, A; Gómez-Caamaño, A; Olay, L; Lara, P C

    2017-02-01

    Assessing the demand for radiotherapy in Spain based on existing evidence to estimate the human resources and equipment needed so that every person in Spain has access to high-quality radiotherapy when they need it. We used data from the European Cancer Observatory on the estimated incidence of cancer in Spain in 2012, along with the evidence-based indications for radiotherapy developed by the Australian CCORE project, to obtain an optimal radiotherapy utilisation proportion (OUP) for each tumour. About 50.5 % of new cancers in Spain require radiotherapy at least once over the course of the disease. Additional demand for these services comes from reradiation therapy and non-melanoma skin cancer. Approximately, 25-30 % of cancer patients with an indication for radiotherapy do not receive it due to factors that include access, patient preference, familiarity with the treatment among physicians, and especially resource shortages, all of which contribute to its underutilisation. Radiotherapy is underused in Spain. The increasing incidence of cancer expected over the next decade and the greater frequency of reradiations necessitate the incorporation of radiotherapy demand into need-based calculations for cancer services planning.

  19. SU-F-T-231: Improving the Efficiency of a Radiotherapy Peer-Review System for Quality Assurance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hsu, S; Basavatia, A; Garg, M

    Purpose: To improve the efficiency of a radiotherapy peer-review system using a commercially available software application for plan quality evaluation and documentation. Methods: A commercial application, FullAccess (Radialogica LLC, Version 1.4.4), was implemented in a Citrix platform for peer-review process and patient documentation. This application can display images, isodose lines, and dose-volume histograms and create plan reports for peer-review process. Dose metrics in the report can also be benchmarked for plan quality evaluation. Site-specific templates were generated based on departmental treatment planning policies and procedures for each disease site, which generally follow RTOG protocols as well as published prospective clinicalmore » trial data, including both conventional fractionation and hypo-fractionation schema. Once a plan is ready for review, the planner exports the plan to FullAccess, applies the site-specific template, and presents the report for plan review. The plan is still reviewed in the treatment planning system, as that is the legal record. Upon physician’s approval of a plan, the plan is packaged for peer review with the plan report and dose metrics are saved to the database. Results: The reports show dose metrics of PTVs and critical organs for the plans and also indicate whether or not the metrics are within tolerance. Graphical results with green, yellow, and red lights are displayed of whether planning objectives have been met. In addition, benchmarking statistics are collected to see where the current plan falls compared to all historical plans on each metric. All physicians in peer review can easily verify constraints by these reports. Conclusion: We have demonstrated the improvement in a radiotherapy peer-review system, which allows physicians to easily verify planning constraints for different disease sites and fractionation schema, allows for standardization in the clinic to ensure that departmental policies are

  20. ORANGE: a Monte Carlo dose engine for radiotherapy.

    PubMed

    van der Zee, W; Hogenbirk, A; van der Marck, S C

    2005-02-21

    This study presents data for the verification of ORANGE, a fast MCNP-based dose engine for radiotherapy treatment planning. In order to verify the new algorithm, it has been benchmarked against DOSXYZ and against measurements. For the benchmarking, first calculations have been done using the ICCR-XIII benchmark. Next, calculations have been done with DOSXYZ and ORANGE in five different phantoms (one homogeneous, two with bone equivalent inserts and two with lung equivalent inserts). The calculations have been done with two mono-energetic photon beams (2 MeV and 6 MeV) and two mono-energetic electron beams (10 MeV and 20 MeV). Comparison of the calculated data (from DOSXYZ and ORANGE) against measurements was possible for a realistic 10 MV photon beam and a realistic 15 MeV electron beam in a homogeneous phantom only. For the comparison of the calculated dose distributions and dose distributions against measurements, the concept of the confidence limit (CL) has been used. This concept reduces the difference between two data sets to a single number, which gives the deviation for 90% of the dose distributions. Using this concept, it was found that ORANGE was always within the statistical bandwidth with DOSXYZ and the measurements. The ICCR-XIII benchmark showed that ORANGE is seven times faster than DOSXYZ, a result comparable with other accelerated Monte Carlo dose systems when no variance reduction is used. As shown for XVMC, using variance reduction techniques has the potential for further acceleration. Using modern computer hardware, this brings the total calculation time for a dose distribution with 1.5% (statistical) accuracy within the clinical range (less then 10 min). This means that ORANGE can be a candidate for a dose engine in radiotherapy treatment planning.

  1. [Big data, generalities and integration in radiotherapy].

    PubMed

    Le Fèvre, C; Poty, L; Noël, G

    2018-02-01

    The many advances in data collection computing systems (data collection, database, storage), diagnostic and therapeutic possibilities are responsible for an increase and a diversification of available data. Big data offers the capacities, in the field of health, to accelerate the discoveries and to optimize the management of patients by combining a large volume of data and the creation of therapeutic models. In radiotherapy, the development of big data is attractive because data are very numerous et heterogeneous (demographics, radiomics, genomics, radiogenomics, etc.). The expectation would be to predict the effectiveness and tolerance of radiation therapy. With these new concepts, still at the preliminary stage, it is possible to create a personalized medicine which is always more secure and reliable. Copyright © 2017. Published by Elsevier SAS.

  2. Dosimetric Comparison in Breast Radiotherapy of 4 MV and 6 MV on Physical Chest Simulator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Donato da Silva, Sabrina; Passos Ribeiro Campos, Tarcisio; Batista Nogueira, Luciana

    2015-07-01

    According to the World Health Organization (2014) breast cancer is the main cause of death by cancer in women worldwide. The biggest challenge of radiotherapy in the treatment of cancer is to deposit the entire prescribed dose homogeneously in the breast, sparing the surrounding tissue. In this context, this paper aimed at evaluating and comparing internal dose distribution in the mammary gland based on experimental procedures submitted to two distinct energy spectra produced in breast cancer radiotherapy. The methodology consisted of reproducing opposite parallel fields used in the treatment of breast tumors in a chest phantom. This simulator with syntheticmore » breast, composed of equivalent tissue material (TE), was previously developed by the NRI Research Group (UFMG). The computer tomography (CT) scan of the simulator was obtained antecedently. The radiotherapy planning systems (TPS) in the chest phantom were performed in the ECLIPSE system from Varian Medical Systems and CAT 3D system from MEVIS. The irradiations were reproduced in the Varian linear accelerator, model SL- 20 Precise, 6 MV energy and Varian linear accelerator, 4 MV Clinac 6x SN11 model. Calibrations of the absorbed dose versus optical density from radiochromic films were generated in order to obtain experimental dosimetric distribution at the films positioned within the glandular and skin equivalent tissues of the chest phantom. The spatial dose distribution showed equivalence with the TPS on measurement data performed in the 6 MV spectrum. The average dose found in radiochromic films placed on the skin ranged from 49 to 79%, and from 39 to 49% in the mammary areola, for the prescribed dose. Dosimetric comparisons between the spectra of 4 and 6 MV, keeping the constant geometry of the fields applied in the same phantom, will be presented showing their equivalence in breast radiotherapy, as well as the variations will be discussed. To sum up, the dose distribution has reached the value

  3. Combination of immunotherapy with chemotherapy and radiotherapy in lung cancer: is this the beginning of the end for cancer?

    PubMed Central

    Lazzari, Chiara; Karachaliou, Niki; Bulotta, Alessandra; Viganó, Mariagrazia; Mirabile, Aurora; Brioschi, Elena; Santarpia, Mariacarmela; Gianni, Luca; Rosell, Rafael; Gregorc, Vanesa

    2018-01-01

    Immune checkpoint inhibitors have significantly improved overall survival with an acceptable safety profile in a substantial proportion of non-small cell lung cancer (NSCLC) patients. However, not all patients are sensitive to immune checkpoint blockade and, in some cases, programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) inhibitors accelerate tumor progression. Several combination strategies are under evaluation, including the concomitant or sequential evaluation of chemotherapy or radiotherapy with immunotherapy. The current review provides an overview on the molecular rationale for the investigation of combinatorial approaches with chemotherapy or radiotherapy. Moreover, the results of completed clinical studies will be reported. PMID:29662546

  4. Combination of immunotherapy with chemotherapy and radiotherapy in lung cancer: is this the beginning of the end for cancer?

    PubMed

    Lazzari, Chiara; Karachaliou, Niki; Bulotta, Alessandra; Viganó, Mariagrazia; Mirabile, Aurora; Brioschi, Elena; Santarpia, Mariacarmela; Gianni, Luca; Rosell, Rafael; Gregorc, Vanesa

    2018-01-01

    Immune checkpoint inhibitors have significantly improved overall survival with an acceptable safety profile in a substantial proportion of non-small cell lung cancer (NSCLC) patients. However, not all patients are sensitive to immune checkpoint blockade and, in some cases, programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) inhibitors accelerate tumor progression. Several combination strategies are under evaluation, including the concomitant or sequential evaluation of chemotherapy or radiotherapy with immunotherapy. The current review provides an overview on the molecular rationale for the investigation of combinatorial approaches with chemotherapy or radiotherapy. Moreover, the results of completed clinical studies will be reported.

  5. Low incidence of new biochemical and clinical hypogonadism following hypofractionated stereotactic body radiation therapy (SBRT) monotherapy for low- to intermediate-risk prostate cancer

    PubMed Central

    2011-01-01

    Background The CyberKnife is an appealing delivery system for hypofractionated stereotactic body radiation therapy (SBRT) because of its ability to deliver highly conformal radiation therapy to moving targets. This conformity is achieved via 100s of non-coplanar radiation beams, which could potentially increase transitory testicular irradiation and result in post-therapy hypogonadism. We report on our early experience with CyberKnife SBRT for low- to intermediate-risk prostate cancer patients and assess the rate of inducing biochemical and clinical hypogonadism. Methods Twenty-six patients were treated with hypofractionated SBRT to a dose of 36.25 Gy in 5 fractions. All patients had histologically confirmed low- to intermediate-risk prostate adenocarcinoma (clinical stage ≤ T2b, Gleason score ≤ 7, PSA ≤ 20 ng/ml). PSA and total testosterone levels were obtained pre-treatment, 1 month post-treatment and every 3 months thereafter, for 1 year. Biochemical hypogonadism was defined as a total serum testosterone level below 8 nmol/L. Urinary and gastrointestinal toxicity was assessed using Common Toxicity Criteria v3; quality of life was assessed using the American Urological Association Symptom Score, Sexual Health Inventory for Men and Expanded Prostate Cancer Index Composite questionnaires. Results All 26 patients completed the treatment with a median 15 months (range, 13-19 months) follow-up. Median pre-treatment PSA was 5.75 ng/ml (range, 2.3-10.3 ng/ml), and a decrease to a median of 0.7 ng/ml (range, 0.2-1.8 ng/ml) was observed by one year post-treatment. The median pre-treatment total serum testosterone level was 13.81 nmol/L (range, 5.55 - 39.87 nmol/L). Post-treatment testosterone levels slowly decreased with the median value at one year follow-up of 10.53 nmol/L, significantly lower than the pre-treatment value (p < 0.013). The median absolute fall was 3.28 nmol/L and the median percent fall was 23.75%. There was no increase in biochemical hypogonadism

  6. Dosimetric comparison of normal structures associated with accelerated partial breast irradiation and whole breast irradiation delivered by intensity modulated radiotherapy for early breast cancer after breast conserving surgery.

    PubMed

    Wu, S; He, Z; Guo, J; Li, F; Lin, Q; Guan, X

    2014-01-01

    To assess the heart and lung dosimetry results associated with accelerated partial breast irradiation intensity-modulated radiotherapy (APBI-IMRT) and whole breast field-in-field intensity-modulated radiotherapy (WBI-FIF-IMRT). A total of 29 patients with early-stage breast cancer after lumpectomy were included in this study. APBI-IMRT and WBI-FIF-IMRT plans were generated for each patient. The dosimetric parameters of ipsilateral lung and heart in both plans were then compared with and without radiobiological correction. With and without radiobiological correction, the volume of ipsilateral lung showed a substantially lower radiation exposure in APBI-IMRT with moderate to high doses (P < 0.05) but non-significant increases in volume of ipsilateral lung in 2.5 Gy than WBI-FIF-IMRT (P > 0.905).There was no significant difference in volume of ipsilateral lung receiving 1, 2.5, and 5 Gy between APBI-IMRT and WBI (P > 0.05) in patients with medial tumor location, although APBI-IMRT exposed more lung to 2.5 and 5 Gy. APBI-IMRT significantly decreases the volume of heart receiving low to high doses in left-sided breast cancer (P < 0.05). APBI-IMRT can significantly spare the volume of heart and ipsilateral lung receiving moderate and high dose. Non-significant increases in volume of the ipsilateral lung exposed to low doses of radiation were observed for APBI-IMRT in comparison to WBI-FIF-IMRT, particularly in patients with medial tumor location. With the increasing interest in APBI-IMRT, our data may help clinicians individualize patient treatment decisions.

  7. Can concomitant-boost accelerated radiotherapy be adopted as routine treatment for head-and-neck cancers? A 10-year single-institution experience.

    PubMed

    Allal, Abdelkarim S; Taussky, Daniel; Mach, Nicolas; Becker, Minerva; Bieri, Sabine; Dulguerov, Pavel

    2004-04-01

    Accelerated schedules are effective in overcoming repopulation during radiotherapy (RT) for head-and-neck cancers, but their feasibility is compromised by increased toxicity. The therapeutic ratio may be particularly favorable for 5-week regimens. This study reports the 10-year experience of a single institution in the routine use of concomitant boost RT as standard radical treatment in all but the most favorable stage patients. Between February 1991 and June 2001, 296 patients (mean age, 59 years) were treated with concomitant boost RT either alone (67%) or combined with cisplatin-based chemotherapy (33%), with a median tumor dose of 69.9 Gy. Tumors were located in the oropharynx in 52%, hypopharynx in 20%, larynx in 15%, nasopharynx in 7%, and oral cavity in 6%. International Union Against Cancer Stage III-IV disease represented 77% of tumors. The median follow-up for surviving patients was 55 months (range, 10-138 months). The RT schedule was completed to the prescribed dose in all but 1 patient. Twenty patients (7%) had a treatment interruption (median, 5 days; range, 2-35 days). Grade 3-4 Radiation Therapy Oncology Group acute toxicity was observed in 77% of patients, and nutritional support was required in 110 patients (37%). For all patients, the 5-year actuarial locoregional control and disease-free survival rate was 72% and 61%, respectively. In a multivariate analysis, only T and N stage was significantly associated with locoregional control and disease-free survival. Grade 3-4 late toxicity occurred in 14%, mostly bone and cartilage necrosis. The present, moderately accelerated, concomitant boost regimen is logistically feasible, causing minimal inconvenience to the technical staff and yielding a high rate of patient compliance. Concomitant chemotherapy administration is feasible provided that patients are carefully selected and supportive care is introduced in a timely fashion. Considering the manageable toxicity and the satisfactory tumor control

  8. The Effect of Postmastectomy Radiation Therapy on Breast Implants: Material Analysis on Silicone and Polyurethane Prosthesis.

    PubMed

    Lo Torto, Federico; Relucenti, Michela; Familiari, Giuseppe; Vaia, Nicola; Casella, Donato; Matassa, Roberto; Miglietta, Selenia; Marinozzi, Franco; Bini, Fabiano; Fratoddi, Ilaria; Sciubba, Fabio; Cassese, Raffaele; Tombolini, Vincenzo; Ribuffo, Diego

    2018-05-17

    The pathogenic mechanism underlying capsular contracture is still unknown. It is certainly a multifactorial process, resulting from human body reaction, biofilm activation, bacteremic seeding, or silicone exposure. The scope of the present article is to investigate the effect of hypofractionated radiotherapy protocol (2.66 Gy × 16 sessions) both on silicone and polyurethane breast implants. Silicone implants and polyurethane underwent irradiation according to a hypofractionated radiotherapy protocol for the treatment of breast cancer. After irradiation implant shells underwent mechanical, chemical, and microstructural evaluation by means of tensile testing, infrared spectra in attenuated total reflectance mode, nuclear magnetic resonance, and field emission scanning electron microscopy. At superficial analysis, irradiated silicone samples show several visible secondary and tertiary blebs. Polyurethane implants showed an open cell structure, which closely resembles a sponge. Morphological observation of struts from treated polyurethane sample shows a more compact structure, with significantly shorter and thicker struts compared with untreated sample. The infrared spectra in attenuated total reflectance mode spectra of irradiated and control samples were compared either for silicon and polyurethane samples. In the case of silicone-based membranes, treated and control specimens showed similar bands, with little differences in the treated one. Nuclear magnetic resonance spectra on the fraction soluble in CDCl3 support these observations. Tensile tests on silicone samples showed a softer behavior of the treated ones. Tensile tests on Polyurethane samples showed no significant differences. Polyurethane implants seem to be more resistant to radiotherapy damage, whereas silicone prosthesis showed more structural, mechanical, and chemical modifications.

  9. Development of C⁶⁺ laser ion source and RFQ linac for carbon ion radiotherapy.

    PubMed

    Sako, T; Yamaguchi, A; Sato, K; Goto, A; Iwai, T; Nayuki, T; Nemoto, K; Kayama, T; Takeuchi, T

    2016-02-01

    A prototype C(6+) injector using a laser ion source has been developed for a compact synchrotron dedicated to carbon ion radiotherapy. The injector consists of a laser ion source and a 4-vane radio-frequency quadrupole (RFQ) linac. Ion beams are extracted from plasma and directly injected into the RFQ. A solenoid guides the low-energy beams into the RFQ. The RFQ is designed to accelerate high-intensity pulsed beams. A structure of monolithic vanes and cavities is adopted to reduce its power consumption. In beam acceleration tests, a solenoidal magnetic field set between the laser ion source and the RFQ helped increase both the peak currents before and after the RFQ by a factor of 4.

  10. Accelerators for charged particle therapy: PAMELA and related issues

    NASA Astrophysics Data System (ADS)

    Peach, Ken

    2014-05-01

    Cancer is a dreadful disease that will affect one in three people at some point in their life; radiotherapy is used in more than half of all cancer treatment, and contributes about 40% to the successful treatment of cancer. Charged Particle Therapy uses protons and other light ions to deliver the lethal dose to the tumor while being relatively sparing of healthy tissue and, because of the finite range of the particles, is able to avoid giving any dose to vital organs. While there are adequate technologies currently available to deliver the required energies and fluxes, the two main technologies (cyclotrons and synchrotrons) have limitations. PAMELA (the Particle Accelerator for MEdicaLApplications) uses the newly-developed non-scaling Fixed Field Alternating Gradient accelerator concepts to deliver therapeutically relevant beams. The status of the development of the PAMELA conceptual design is discussed.

  11. A dosimetry technique for measuring kilovoltage cone‐beam CT dose on a linear accelerator using radiotherapy equipment

    PubMed Central

    Lawford, Catherine E.

    2014-01-01

    This work develops a technique for kilovoltage cone‐beam CT (CBCT) dosimetry that incorporates both point dose and integral dose in the form of dose length product, and uses readily available radiotherapy equipment. The dose from imaging protocols for a range of imaging parameters and treatment sites was evaluated. Conventional CT dosimetry using 100 mm long pencil chambers has been shown to be inadequate for the large fields in CBCT and has been replaced in this work by a combination of point dose and integral dose. Absolute dose measurements were made with a small volume ion chamber at the central slice of a radiotherapy phantom. Beam profiles were measured using a linear diode array large enough to capture the entire imaging field. These profiles were normalized to absolute dose to form dose line integrals, which were then weighted with radial depth to form the DLPCBCT. This metric is analogous to the standard dose length product (DLP), but derived differently to suit the unique properties of CBCT. Imaging protocols for head and neck, chest, and prostate sites delivered absolute doses of 0.9, 2.2, and 2.9 cGy to the center of the phantom, and DLPCBCT of 28.2, 665.1, and 565.3 mGy.cm, respectively. Results are displayed as dose per 100 mAs and as a function of key imaging parameters such as kVp, mAs, and collimator selection in a summary table. DLPCBCT was found to correlate closely with the dimension of the imaging region and provided a good indication of integral dose. It is important to assess integral dose when determining radiation doses to patients using CBCT. By incorporating measured beam profiles and DLP, this technique provides a CBCT dosimetry in radiotherapy phantoms and allows the prediction of imaging dose for new CBCT protocols. PACS number: 87.57.uq PMID:25207398

  12. A dosimetry technique for measuring kilovoltage cone-beam CT dose on a linear accelerator using radiotherapy equipment.

    PubMed

    Scandurra, Daniel; Lawford, Catherine E

    2014-07-08

    This work develops a technique for kilovoltage cone-beam CT (CBCT) dosimetry that incorporates both point dose and integral dose in the form of dose length product, and uses readily available radiotherapy equipment. The dose from imaging protocols for a range of imaging parameters and treatment sites was evaluated. Conventional CT dosimetry using 100 mm long pencil chambers has been shown to be inadequate for the large fields in CBCT and has been replaced in this work by a combination of point dose and integral dose. Absolute dose measurements were made with a small volume ion chamber at the central slice of a radiotherapy phantom. Beam profiles were measured using a linear diode array large enough to capture the entire imaging field. These profiles were normalized to absolute dose to form dose line integrals, which were then weighted with radial depth to form the DLPCBCT. This metric is analogous to the standard dose length product (DLP), but derived differently to suit the unique properties of CBCT. Imaging protocols for head and neck, chest, and prostate sites delivered absolute doses of 0.9, 2.2, and 2.9 cGy to the center of the phantom, and DLPCBCT of 28.2, 665.1, and 565.3mGy.cm, respectively. Results are displayed as dose per 100 mAs and as a function of key imaging parameters such as kVp, mAs, and collimator selection in a summary table. DLPCBCT was found to correlate closely with the dimension of the imaging region and provided a good indication of integral dose. It is important to assess integral dose when determining radiation doses to patients using CBCT. By incorporating measured beam profiles and DLP, this technique provides a CBCT dosimetry in radiotherapy phantoms and allows the prediction of imaging dose for new CBCT protocols.

  13. Prospective study of cone-beam computed tomography image-guided radiotherapy for prone accelerated partial breast irradiation.

    PubMed

    Jozsef, Gabor; DeWyngaert, J Keith; Becker, Stewart J; Lymberis, Stella; Formenti, Silvia C

    2011-10-01

    To report setup variations during prone accelerated partial breast irradiation (APBI). New York University (NYU) 07-582 is an institutional review board-approved protocol of cone-beam computed tomography (CBCT) to deliver image-guided ABPI in the prone position. Eligible are postmenopausal women with pT1 breast cancer excised with negative margins and no nodal involvement. A total dose of 30 Gy in five daily fractions of 6 Gy are delivered to the planning target volume (the tumor cavity with 1.5-cm margin) by image-guided radiotherapy. Patients are set up prone, on a dedicated mattress, used for both simulation and treatment. After positioning with skin marks and lasers, CBCTs are performed and the images are registered to the planning CT. The resulting shifts (setup corrections) are recorded in the three principal directions and applied. Portal images are taken for verification. If they differ from the planning digital reconstructed radiographs, the patient is reset, and a new CBCT is taken. 70 consecutive patients have undergone a total of 343 CBCTs: 7 patients had four of five planned CBCTs performed. Seven CBCTs (2%) required to be repeated because of misalignment in the comparison between portal and digital reconstructed radiograph image after the first CBCT. The mean shifts and standard deviations in the anterior-posterior (AP), superior-inferior (SI), and medial-lateral (ML) directions were -0.19 (0.54), -0.02 (0.33), and -0.02 (0.43) cm, respectively. The average root mean squares of the daily shifts were 0.50 (0.28), 0.29 (0.17), and 0.38 (0.20). A conservative margin formula resulted in a recommended margin of 1.26, 0.73, 0.96 cm in the AP, SI, and ML directions. CBCTs confirmed that the NYU prone APBI setup and treatment technique are reproducible, with interfraction variation comparable to those reported for supine setup. The currently applied margin (1.5 cm) adequately compensates for the setup variation detected. Copyright © 2011 Elsevier Inc. All

  14. Radiotherapy.

    PubMed

    Krause, Sonja; Debus, Jürgen; Neuhof, Dirk

    2011-01-01

    Solitary plasmocytoma occurring in bone (solitary plasmocytoma of the bone, SBP) or in soft tissue (extramedullary plasmocytoma, EP) can be treated effectively and with little toxicity by local radiotherapy. Ten-year local control rates of up to 90% can be achieved. Patients with multiple myeloma often suffer from symptoms such as pain or neurological impairments that are amenable to palliative radiotherapy. In a palliative setting, short treatment schedules and lower radiation doses are used to reduce toxicity and duration of hospitalization. In future, low-dose total body irradiation (TBI) may play a role in a potentially curative regimen with nonmyeloablative conditioning followed by allogenic peripheral blood stem cell transplantation.

  15. Sphere of equivalence--a novel target volume concept for intraoperative radiotherapy using low-energy X rays.

    PubMed

    Herskind, Carsten; Griebel, Jürgen; Kraus-Tiefenbacher, Uta; Wenz, Frederik

    2008-12-01

    Accelerated partial breast radiotherapy with low-energy photons from a miniature X-ray machine is undergoing a randomized clinical trial (Targeted Intra-operative Radiation Therapy [TARGIT]) in a selected subgroup of patients treated with breast-conserving surgery. The steep radial dose gradient implies reduced tumor cell control with increasing depth in the tumor bed. The purpose was to compare the expected risk of local recurrence in this nonuniform radiation field with that after conventional external beam radiotherapy. The relative biologic effectiveness of low-energy photons was modeled using the linear-quadratic formalism including repair of sublethal lesions during protracted irradiation. Doses of 50-kV X-rays (Intrabeam) were converted to equivalent fractionated doses, EQD2, as function of depth in the tumor bed. The probability of local control was estimated using a logistic dose-response relationship fitted to clinical data from fractionated radiotherapy. The model calculations show that, for a cohort of patients, the increase in local control in the high-dose region near the applicator partly compensates the reduction of local control at greater distances. Thus a "sphere of equivalence" exists within which the risk of recurrence is equal to that after external fractionated radiotherapy. The spatial distribution of recurrences inside this sphere will be different from that after conventional radiotherapy. A novel target volume concept is presented here. The incidence of recurrences arising in the tumor bed around the excised tumor will test the validity of this concept and the efficacy of the treatment. Recurrences elsewhere will have implications for the rationale of TARGIT.

  16. Radiotherapy and risk of implantable cardioverter-defibrillator malfunctions: experimental data from direct exposure at increasing doses.

    PubMed

    Zecchin, Massimo; Artico, Jessica; Morea, Gaetano; Severgnini, Mara; Bianco, Elisabetta; De Luca, Antonio; Fantasia, Anna Zorzin; Salvatore, Luca; Milan, Vittorino; Lucarelli, Matteo; Dissegna, Roberta; Cannatà, Antonio; Sinagra, Gianfranco

    2018-04-01

    During radiotherapy, in patients with implantable cardioverter-defibrillators (ICDs) malfunctions are considered more likely if doses more than 2 Gy reach the ICD site; however, most malfunctions occur with high-energy (>10 MV) radiations, and the risk is less defined using 6-MV linear accelerators. The purpose of the study is to experimentally evaluate the occurrence of malfunctions in ICDs radiated with a 6-MV linear accelerator at increasing photon doses. Thirty-two ICDs from all manufacturers (31 explanted and one demo) were evaluated; all devices with a sufficient battery charge underwent multiple radiations with a 6-MV photon beam reaching a cumulative dose at ICD site of 0.5, 1, 2, 3, 5 and 10 Gy and interrogated after every session. All antitachycardia therapies were left enabled; two ICDs were connected to a rhythm simulator (one simulating a complete atrioventricular block without ventricular activity) and visually monitored by external ECG and the ICD programmer during radiation. Thirteen ICDs were excluded before radiation because of battery depletion; after radiation up to the cumulative dose at the cardiac implantable electronic device site of 10 Gy, in the remaining 19 devices, programmation and battery charge remained unchanged and no switch to safety mode was observed; oversensing, pacing inhibition or inappropriate antitachycardia therapy were neither recorded nor visually observed during radiation. With a low-energy accelerator, neither malfunctions nor electromagnetic interferences were detected radiating the ICDs at doses usually reaching the ICD pocket during radiotherapy sessions. In this context, magnet application to avoid oversensing and inappropriate therapy seems, therefore, useless.

  17. Establishment of a National Accelerator Facility: Design and construction phase

    NASA Astrophysics Data System (ADS)

    1981-06-01

    The main components of an accelerator facility for nuclear physics, isotope production, and radiotherapy in South Africa are in 8-MeV solid pole injector cyclotron and a separated sector cyclotron with a k-value of 200 MeV. Progress made in the development of the light ion injector and in the design of the control and beam transport systems is described. Mechanical and engineering tasks associated with component manufacture are discussed as well as the construction of the building to house the facility and the installation of necessary services.

  18. Particle Accelerator Applications: Ion and Electron Irradiation in Materials Science, Biology and Medicine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rodriguez-Fernandez, Luis

    2010-09-10

    Although the developments of particle accelerators are devoted to basic study of matter constituents, since the beginning these machines have been applied with different purposes in many areas also. Today particle accelerators are essential instruments for science and technology. This work presents an overview of the main application for direct particle irradiation with accelerator in material science, biology and medicine. They are used for material synthesis by ion implantation and charged particle irradiation; to make coatings and micromachining; to characterize broad kind of samples by ion beam analysis techniques; as mass spectrometers for atomic isotopes determination. In biomedicine the acceleratorsmore » are applied for the study of effects by charged particles on cells. In medicine the radiotherapy by electron irradiation is widely used, while hadrontherapy is still under development. Also, they are necessary for short life radioisotopes production required in radiodiagnostic.« less

  19. Dose Escalation of Whole-Brain Radiotherapy for Brain Metastases From Melanoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rades, Dirk, E-mail: Rades.Dirk@gmx.ne; Heisterkamp, Christine; Huttenlocher, Stefan

    2010-06-01

    Purpose: The majority of patients with brain metastases from melanoma receive whole-brain radiotherapy (WBRT). However, the results are poor. Hypofractionation regimens failed to improve the outcome of these patients. This study investigates a potential benefit from escalation of the WBRT dose beyond the 'standard' regimen 30 Gy in 10 fractions (10x3 Gy). Methods and Materials: Data from 51 melanoma patients receiving WBRT alone were retrospectively analyzed. A dosage of 10x3 Gy (n = 33) was compared with higher doses including 40 Gy/20 fractions (n = 11) and 45 Gy/15 fractions (n = 7) for survival (OS) and local (intracerebral) controlmore » (LC). Additional potential prognostic factors were evaluated: age, gender, performance status, number of metastases, extracerebral metastases, and recursive partitioning analysis (RPA) class. Results: At 6 months, OS rates were 27% after 10x3 Gy and 50% after higher doses (p = 0.009). The OS rates at 12 months were 4% and 20%. On multivariate analysis, higher WBRT doses (p = 0.010), fewer than four brain metastases (p = 0.012), no extracerebral metastases (p = 0.006), and RPA class 1 (p = 0.005) were associated with improved OS. The LC rates at 6 months were 23% after 10x3 Gy and 50% after higher doses (p = 0.021). The LC rates at 12 months were 0% and 13%. On multivariate analysis, higher WBRT doses (p = 0.020) and fewer than brain metastases (p = 0.002) were associated with better LC. Conclusions: Given the limitations of a retrospective study, the findings suggest that patients with brain metastases from melanoma receiving WBRT alone may benefit from dose escalation beyond 10x3 Gy. The hypothesis generated by this study must be confirmed in a randomized trial stratifying for significant prognostic factors.« less

  20. Interfraction Prostate Movement in Bone Alignment After Rectal Enema for Radiotherapy

    PubMed Central

    Seo, Young Eun; Kim, Tae Hyo; Lee, Ki Soo; Cho, Won Yeol; Lee, Hyung-Sik; Hur, Won-Joo

    2014-01-01

    Purpose To assess the effect of a rectal enema on interfraction prostate movement in bone alignment (BA) for prostate radiotherapy (RT), we analyzed the spatial difference in prostates in a bone-matched setup. Materials and Methods We performed BA retrospectively with data from prostate cancer patients who underwent image-guided RT (IGRT). The prostate was identified with implanted fiducial markers. The setup for the IGRT was conducted with the matching of three fiducial markers on RT planning computed tomography images and those on two oblique kV x-ray images. Offline BA was performed at the same position. The coordinates of a virtual prostate in BA and a real prostate were obtained by use of the ExaxTrac/NovalisBody system, and the distance between them was calculated as the spatial difference. Interfraction prostate displacement was drawn from the comparison of the spatial differences. Results A total of 15 patients with localized prostate cancer treated with curative hypofractionated IGRT were enrolled. A total of 420 fractions were analyzed. The mean of the interfraction prostate displacements after BA was 3.12±2.00 mm (range, 0.20-10.53 mm). The directional difference was profound in the anterior-posterior and supero-inferior directions (2.14±1.73 mm and 1.97±1.44 mm, respectively) compared with the right-left direction (0.26±0.22 mm, p<0.05). The required margin around the clinical target volume was 4.97 mm with the formula of van Herk et al. Conclusions The interfraction prostate displacement was less frequent when a rectal enema was performed before the procedure. A rectal enema can be used to reduce interfraction prostate displacement and resulting clinical target volume-to-planning target volume margin. PMID:24466393

  1. PTV margin definition in hypofractionated IGRT of localized prostate cancer using cone beam CT and orthogonal image pairs with fiducial markers.

    PubMed

    Oehler, Christoph; Lang, Stephanie; Dimmerling, Peter; Bolesch, Christian; Kloeck, Stephan; Tini, Alessandra; Glanzmann, Christoph; Najafi, Yousef; Studer, Gabriela; Zwahlen, Daniel R

    2014-11-11

    To evaluate PTV margins for hypofractionated IGRT of prostate comparing kV/kV imaging or CBCT. Between 2009 and 2012, 20 patients with low- (LR), intermediate- (IR) and high-risk (HR) prostate cancer were treated with VMAT in supine position with fiducial markers (FM), endorectal balloon (ERB) and full bladder. CBCT's and kV/kV imaging were performed before and additional CBCT's after treatment assessing intra-fraction motion. CTVP for 5 patients with LR and CTVPSV for 5 patients with IR/HR prostate cancer were contoured independently by 3 radiation oncologists using MRI. The van Hark formula (PTV margin =2.5Σ +0.7σ) was applied to calculate PTV margins of prostate/seminal vesicles (P/PSV) using CBCT or FM. 172 and 52 CBCTs before and after RT and 507 kV/kV images before RT were analysed. Differences between FM in CBCT or in planar kV image pairs were below 1 mm. Accounting for both random and systematic uncertainties anisotropic PTV margins were 5-8 mm for P (LR) and 6-11 mm for PSV (IR/HR). Random uncertainties like intra-fraction and inter-fraction (setup) uncertainties were of similar magnitude (0.9-1.4 mm). Largest uncertainty was introduced by CTV delineation (LR: 1-2 mm, IR/HR: 1.6-3.5 mm). Patient positioning using bone matching or ERB-matching resulted in larger PTV margins. For IGRT CBCT or kV/kV-image pairs with FM are interchangeable in respect of accuracy. Especially for hypofractionated RT, PTV margins can be kept in the range of 5 mm or below if stringent daily IGRT, ideally including prostate tracking, is applied. MR-based CTV delineation optimization is recommended.

  2. Hypofractionated Radiation Therapy (66 Gy in 22 Fractions at 3 Gy per Fraction) for Favorable-Risk Prostate Cancer: Long-term Outcomes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patel, Nita; Faria, Sergio, E-mail: sergio.faria@muhc.mcgill.ca; Cury, Fabio

    2013-07-01

    Purpose: To report long-term outcomes of low- and intermediate-risk prostate cancer patients treated with high-dose hypofractionated radiation therapy (HypoRT). Methods and Materials: Patients with low- and intermediate-risk prostate cancer were treated using 3-dimensional conformal radiation therapy to a dose of 66 Gy in 22 daily fractions of 3 Gy without hormonal therapy. A uniform 7-mm margin was created around the prostate for the planning target volume, and treatment was prescribed to the isocenter. Treatment was delivered using daily ultrasound image-guided radiation therapy. Common Terminology Criteria for Adverse Events, version 3.0, was used to prospectively score toxicity. Biochemical failure was definedmore » as the nadir prostate-specific antigen level plus 2 ng/mL. Results: A total of 129 patients were treated between November 2002 and December 2005. With a median follow-up of 90 months, the 5- and 8-year actuarial biochemical control rates were 97% and 92%, respectively. The 5- and 8-year actuarial overall survival rates were 92% and 88%, respectively. Only 1 patient died from prostate cancer at 92 months after treatment, giving an 8-year actuarial cancer-specific survival of 98%. Radiation therapy was well tolerated, with 57% of patients not experiencing any acute gastrointestinal (GI) or genitourinary (GU) toxicity. For late toxicity, the worst grade ≥2 rate for GI and GU toxicity was 27% and 33%, respectively. There was no grade >3 toxicity. At last follow-up, the rate of grade ≥2 for both GI and GU toxicity was only 1.5%. Conclusions: Hypofractionation with 66 Gy in 22 fractions prescribed to the isocenter using 3-dimensional conformal radiation therapy produces excellent biochemical control rates, with moderate toxicity. However, this regimen cannot be extrapolated to the intensity modulated radiation therapy technique.« less

  3. Precision Hypofractionated Radiation Therapy in Poor Performing Patients With Non-Small Cell Lung Cancer: Phase 1 Dose Escalation Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Westover, Kenneth D.; Loo, Billy W.; Gerber, David E.

    2015-09-01

    Purpose: Treatment regimens for locally advanced non-small cell lung cancer (NSCLC) give suboptimal clinical outcomes. Technological advancements such as radiation therapy, the backbone of most treatment regimens, may enable more potent and effective therapies. The objective of this study was to escalate radiation therapy to a tumoricidal hypofractionated dose without exceeding the maximally tolerated dose (MTD) in patients with locally advanced NSCLC. Methods and Materials: Patients with stage II to IV or recurrent NSCLC and Eastern Cooperative Oncology Group performance status of 2 or greater and not candidates for surgical resection, stereotactic radiation, or concurrent chemoradiation were eligible. Highly conformal radiationmore » therapy was given to treat intrathoracic disease in 15 fractions to a total of 50, 55, or 60 Gy. Results: Fifty-five patients were enrolled: 15 at the 50-Gy, 21 at the 55-Gy, and 19 at the 60-Gy dose levels. A 90-day follow-up was completed in each group without exceeding the MTD. With a median follow-up of 12.5 months, there were 93 grade ≥3 adverse events (AEs), including 39 deaths, although most AEs were considered related to factors other than radiation therapy. One patient from the 55- and 60-Gy dose groups developed grade ≥3 esophagitis, and 5, 4, and 4 patients in the respective dose groups experienced grade ≥3 dyspnea, but only 2 of these AEs were considered likely related to therapy. There was no association between fraction size and toxicity (P=.24). The median overall survival was 6 months with no significant differences between dose levels (P=.59). Conclusions: Precision hypofractionated radiation therapy consisting of 60 Gy in 15 fractions for locally advanced NSCLC is generally well tolerated. This treatment regimen could provide patients with poor performance status a potent alternative to chemoradiation. This study has implications for the cost effectiveness of lung cancer therapy. Additional studies of

  4. Clinical Outcomes of Image Guided Adaptive Hypofractionated Weekly Radiation Therapy for Bladder Cancer in Patients Unsuitable for Radical Treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hafeez, Shaista, E-mail: shaista.hafeez@icr.ac.uk; The Royal Marsden NHS Foundation Trust, Sutton, Surrey; McDonald, Fiona

    Purpose and Objectives: We report on the clinical outcomes of a phase 2 study assessing image guided hypofractionated weekly radiation therapy in bladder cancer patients unsuitable for radical treatment. Methods and Materials: Fifty-five patients with T2-T4aNx-2M0-1 bladder cancer not suitable for cystectomy or daily radiation therapy treatment were recruited. A “plan of the day” radiation therapy approach was used, treating the whole (empty) bladder to 36 Gy in 6 weekly fractions. Acute toxicity was assessed weekly during radiation therapy, at 6 and 12 weeks using the Common Terminology Criteria for Adverse Events version 3.0. Late toxicity was assessed at 6 months and 12 monthsmore » using Radiation Therapy Oncology Group grading. Cystoscopy was used to assess local control at 3 months. Cumulative incidence function was used to determine local progression at 1 at 2 years. Death without local progression was treated as a competing risk. Overall survival was estimated using the Kaplan-Meier method. Results: Median age was 86 years (range, 68-97 years). Eighty-seven percent of patients completed their prescribed course of radiation therapy. Genitourinary and gastrointestinal grade 3 acute toxicity was seen in 18% (10/55) and 4% (2/55) of patients, respectively. No grade 4 genitourinary or gastrointestinal toxicity was seen. Grade ≥3 late toxicity (any) at 6 and 12 months was seen in 6.5% (2/31) and 4.3% (1/23) of patients, respectively. Local control after radiation therapy was 92% of assessed patients (60% total population). Cumulative incidence of local progression at 1 year and 2 years for all patients was 7% (95% confidence interval [CI] 2%-17%) and 17% (95% CI 8%-29%), respectively. Overall survival at 1 year was 63% (95% CI 48%-74%). Conclusion: Hypofractionated radiation therapy delivered weekly with a plan of the day approach offers good local control with acceptable toxicity in a patient population not suitable for radical bladder

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Janssens, Geert O.R.J.; Gidding, Corrie E.M.; Lindert, Erik J. van

    Purpose: Most children with a diffuse intrinsic brainstem glioma will die within 1 year after diagnosis. To reduce patient burden, we investigated the feasibility of a radical hypofractionation radiotherapy schedule, given over 3 weeks, as an alternative to the standard regimen (30 fractions over 6 weeks). Methods and Materials: Nine children, ages 3-13, were treated by 13 fractions of 3 Gy (n = 8) or 6 fractions of 5.5 Gy (n = 1) given over 3 weeks. All patients had symptoms for {<=}3 months and {>=}2 signs of the neurologic triad (long tract signs, ataxia, cranial nerve deficit). Bilateral involvementmore » of the pons (n = 8), encasement of the basilar artery (n = 7) and extension into the cerebellar peduncle (n = 6) was visible on magnetic resonance imaging. Results: Symptom improvement occurred in all patients within 2 weeks after start of radiotherapy. At a mean follow-up time of 15 months, 7 patients have died. Median time to progression and overall survival was 4.9 and 8.6 months, respectively. Median time to death after progression was 3.6 months. No Grade 3 or 4 toxicity was observed. In a recently published review of clinical trials, median time to progression, overall survival, and time between progression and death ranged from 5.0-8.8, 7.0-16, and 1.0-4.5 months, respectively, with more aggressive regimens. Conclusion: This radical hypofractionation radiotherapy regimen for children with diffuse intrinsic brainstem glioma is feasible and associated with no Grade 3 or 4 toxicities. With a minimal overall treatment time, it offers quick symptom relief and outcome results within the range of published data.« less

  6. Rho inhibition by lovastatin affects apoptosis and DSB repair of primary human lung cells in vitro and lung tissue in vivo following fractionated irradiation

    PubMed Central

    Ziegler, Verena; Henninger, Christian; Simiantonakis, Ioannis; Buchholzer, Marcel; Ahmadian, Mohammad Reza; Budach, Wilfried; Fritz, Gerhard

    2017-01-01

    Thoracic radiotherapy causes damage of normal lung tissue, which limits the cumulative radiation dose and, hence, confines the anticancer efficacy of radiotherapy and impacts the quality of life of tumor patients. Ras-homologous (Rho) small GTPases regulate multiple stress responses and cell death. Therefore, we investigated whether pharmacological targeting of Rho signaling by the HMG-CoA-reductase inhibitor lovastatin influences ionizing radiation (IR)-induced toxicity in primary human lung fibroblasts, lung epithelial and lung microvascular endothelial cells in vitro and subchronic mouse lung tissue damage following hypo-fractionated irradiation (4x4 Gy). The statin improved the repair of radiation-induced DNA double-strand breaks (DSBs) in all cell types and, moreover, protected lung endothelial cells from IR-induced caspase-dependent apoptosis, likely involving p53-regulated mechanisms. Under the in vivo situation, treatment with lovastatin or the Rac1-specific small molecule inhibitor EHT1864 attenuated the IR-induced increase in breathing frequency and reduced the percentage of γH2AX and 53BP1-positive cells. This indicates that inhibition of Rac1 signaling lowers IR-induced residual DNA damage by promoting DNA repair. Moreover, lovastatin and EHT1864 protected lung tissue from IR-triggered apoptosis and mitigated the IR-stimulated increase in regenerative proliferation. Our data document beneficial anti-apoptotic and genoprotective effects of pharmacological targeting of Rho signaling following hypo-fractionated irradiation of lung cells in vitro and in vivo. Rac1-targeting drugs might be particular useful for supportive care in radiation oncology and, moreover, applicable to improve the anticancer efficacy of radiotherapy by widening the therapeutic window of thoracic radiation exposure. PMID:28796249

  7. Continuous 28-day iododeoxyuridine infusion and hyperfractionated accelerated radiotherapy for malignant glioma: a phase I clinical study.

    PubMed

    Schulz, Craig A; Mehta, Minesh P; Badie, Benham; McGinn, Cornelius J; Robins, H Ian; Hayes, Lori; Chappell, Rick; Volkman, Jen; Binger, Kim; Arzoomanian, Rhoda; Simon, Kris; Alberti, Dona; Feierabend, Christine; Tutsch, Kendra D; Kunugi, Keith A; Wilding, George; Kinsella, Timothy J

    2004-07-15

    To investigate the maximal tolerated dose of a continuous 28-day iododeoxyuridine (IUdr) infusion combined with hyperfractionated accelerated radiotherapy (HART); to analyze the percentage of IUdr-thymidine replacement in peripheral granulocytes as a surrogate marker for IUdr incorporation into tumor cells; to measure the steady-state serum IUdr levels; and to assess the feasibility of continuous IUdr infusion and HART in the management of malignant glioma. Patients were required to have biopsy-proven malignant glioma. Patients received 100 (n = 4), 200 (n = 3), 300 (n = 3), 400 (n = 6), 500 (n = 4), 625 (n = 5), or 781 (n = 6) mg/m(2)/d of IUdr by continuous infusion for 28 days. HART was started 7 days after IUdr initiation. The total dose was 70 Gy (1.2 Gy b.i.d. for 25 days with a 10-Gy boost [2.0 Gy for 5 Saturdays]). Weekly assays were performed to determine the percentage of IUdr-DNA replacement in granulocytes and serum IUdr levels using standard high performance liquid chromatography methods. Standard Phase I toxicity methods were used. Between June 1994 and August 1999, 31 patients were enrolled. No patient had Grade 3 or worse HART toxicity. Grade 3 or greater IUdr toxicity predominantly included neutropenia (n = 3), thrombocytopenia (n = 3), and elevated liver function studies (n = 3). The maximal tolerated dose was 625 mg/m(2)/d. Thymidine replacement in the peripheral granulocytes peaked at 3 weeks and increased with the dose (maximal thymidine replacement 4.9%). The steady-state plasma IUdr level increased with the dose (maximum, 1.5 microM). In our study, continuous long-term IUdr i.v. infusion had a maximal tolerated dose of 625 mg/m(2)/d. Granulocyte incorporation data verified the concept that prolonged IUdr infusion results in IUdr-DNA replacement that corresponds to a high degree of cell labeling. IUdr steady-state plasma levels increased with increasing dose and attained levels needed for clinical radiosensitization. Continuous IUdr infusion

  8. Radiochemotherapy With Cetuximab, Cisplatin, and Amifostine for Locally Advanced Head and Neck Cancer: A Feasibility Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koukourakis, Michael I., E-mail: targ@her.forthnet.g; Tsoutsou, Pelagia G.; Karpouzis, Antonios

    2010-05-01

    Purpose: Radiotherapy (RT) combined with cisplatin or cetuximab is the standard of care for patients with locally advanced head/neck cancer (LA-HNC). The feasibility of radiochemotherapy with cisplatin and cetuximab, supported with amifostine, was herein investigated. Methods and Materials: Forty-three patients with LA-HNC were recruited. Conformal hypofractionated/accelerated RT with amifostine cytoprotection (2.7 Gy/fraction, 21 fractions in 4 weeks) was combined with cisplatin (30 mg/m{sup 2}/week) and cetuximab (standard weekly regimen) therapy. The dose of amifostine was individualized according to tolerance. Results: A high daily amifostine dose (750-1,000 mg) was tolerated by 41.8% of patients, and a standard dose (500 mg) wasmore » tolerated by 34.9% of patients. A high amifostine dose was linked to reduced RT delays (p = 0.0003). Grade 3 to 4 (3-4) mucositis occurred in 7/43 (16.2%) patients, and fungal infections occurred in 18/43 (41.8%) patients. Radiation dermatitis was not aggravated. Interruption of cetuximab due to acneiform rash was necessary in 23.3% of patients, while amifostine-related fever and rash were not observed. Severe late radiation sequelae consisted of laryngeal edema (9% laryngeal cases) and cervical strictures (33% of hypopharyngeal cases). Good salivary function was preserved in 6/11 (54.5%) nasopharyngeal cancer patients. The complete response rate was 68.5%, reaching 77.2% in patients with minor radiotherapy delays. The 24-month local control and survival rates were 72.3% and 91%, respectively (median follow-up was 13 months.). Conclusions: In this feasibility study, weekly administration of cisplatin and cetuximab was safely combined with accelerated RT, supported with amifostine, at the cost of a high incidence of acneiform rash but a reduced incidence of amifostine-related fever/rash. A high daily dose of amifostine allows completion of therapy with minor delays.« less

  9. Measuring neutron spectra in radiotherapy using the nested neutron spectrometer.

    PubMed

    Maglieri, Robert; Licea, Angel; Evans, Michael; Seuntjens, Jan; Kildea, John

    2015-11-01

    Out-of-field neutron doses resulting from photonuclear interactions in the head of a linear accelerator pose an iatrogenic risk to patients and an occupational risk to personnel during radiotherapy. To quantify neutron production, in-room measurements have traditionally been carried out using Bonner sphere systems (BSS) with activation foils and TLDs. In this work, a recently developed active detector, the nested neutron spectrometer (NNS), was tested in radiotherapy bunkers. The NNS is designed for easy handling and is more practical than the traditional BSS. Operated in current-mode, the problem of pulse pileup due to high dose-rates is overcome by measuring current, similar to an ionization chamber. In a bunker housing a Varian Clinac 21EX, the performance of the NNS was evaluated in terms of reproducibility, linearity, and dose-rate effects. Using a custom maximum-likelihood expectation-maximization algorithm, measured neutron spectra at various locations inside the bunker were then compared to Monte Carlo simulations of an identical setup. In terms of dose, neutron ambient dose equivalents were calculated from the measured spectra and compared to bubble detector neutron dose equivalent measurements. The NNS-measured spectra for neutrons at various locations in a treatment room were found to be consistent with expectations for both relative shape and absolute magnitude. Neutron fluence-rate decreased with distance from the source and the shape of the spectrum changed from a dominant fast neutron peak near the Linac head to a dominant thermal neutron peak in the moderating conditions of the maze. Monte Carlo data and NNS-measured spectra agreed within 30% at all locations except in the maze where the deviation was a maximum of 40%. Neutron ambient dose equivalents calculated from the authors' measured spectra were consistent (one standard deviation) with bubble detector measurements in the treatment room. The NNS may be used to reliably measure the neutron

  10. Skyshine photon doses from 6 and 10 MV medical linear accelerators.

    PubMed

    de Paiva, Eduardo; da Rosa, Luiz A R

    2012-01-05

    The skyshine radiation phenomenon consists of the scattering of primary photon beams in the atmosphere above the roof of a medical linear accelerator facility, generating an additional dose at ground level in the vicinity of the treatment room. Thus, with respect to radioprotection, this situation plays an important role when the roof is designed with little shielding and there are buildings next to the radiotherapy treatment room. In literature, there are few reported skyshine-measured doses and these contain poor agreement with empirical calculations. In this work, we carried out measurements of skyshine photon dose rates produced from eight different 6 and 10 MV medical accelerators. Each measurement was performed outside the room facility, with the beam positioned in the upward direction, at a horizontal distance from the target and for a 40 cm × 40 cm maximum photon field size at the accelerator isocenter. Measured dose-equivalent rates results were compared with calculations obtained by an empirical expression, and differences between them deviated in one or more order of magnitude.

  11. Melatonin prevents possible radiotherapy-induced thyroid injury.

    PubMed

    Arıcıgil, Mitat; Dündar, Mehmet Akif; Yücel, Abitter; Eryılmaz, Mehmet Akif; Aktan, Meryem; Alan, Mehmet Akif; Fındık, Sıdıka; Kılınç, İbrahim

    2017-12-01

    We aimed to investigate the protective effect of melatonin in radiotherapy-induced thyroid gland injury in an experimental rat model. Thirty-two rats were divided into four groups: the control group, melatonin treatment group, radiotherapy group and melatonin plus radiotherapy group. The neck region of each rat was defined by simulation and radiated with 2 Gray (Gy) per min with 6-MV photon beams, for a total dose of 18 Gy. Melatonin was administered at a dose of 50 mg/kg through intraperitoneal injection, 15 min prior to radiation exposure. Thirty days after the beginning of the study, rats were decapitated and analyses of blood and thyroid tissue were performed. Tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β), thiobarbituric acid reactive substances (TBARS) and nitric oxide (NO) levels in the radiotherapy group were significantly higher than those in the melatonin plus radiotherapy group (p < .05), whereas interleukin-10 (IL-10) and glutathione (GSH) values were higher in the melatonin plus radiotherapy group (p < .05). The infiltration of inflammatory cells and percentage of apoptosis in the radiotherapy group were significantly higher than those in the melatonin plus radiotherapy group (p < .05). Melatonin helped protect thyroid gland structure against the undesired cytotoxic effects of radiotherapy in rats.

  12. Examining Determinants of Radiotherapy Access: Do Cost and Radiotherapy Inconvenience Affect Uptake of Breast-conserving Treatment for Early Breast Cancer?

    PubMed

    Lam, J; Cook, T; Foster, S; Poon, R; Milross, C; Sundaresan, P

    2015-08-01

    Radiotherapy utilisation is likely affected by multiple factors pertaining to radiotherapy access. Radiotherapy is an integral component of breast-conserving treatment (BCT) for early breast cancer. We aimed to determine if stepwise improvements in radiotherapy access in regional Australia affected the uptake of BCT and thus radiotherapy. Breast cancer operations in the Central Coast of New South Wales between January 2010 and March 2014 for T1-2N0-1M0 invasive or in situ (≤5 cm) disease in female patients eligible for BCT were examined. BCT uptake was calculated for three 1 year periods: period 1 (local radiotherapy available at cost to user or out of area radiotherapy with travel cost and inconvenience); period 2 (as per period 1 + publicly funded transport and radiotherapy at out of area facilities at no cost to user); period 3 (as per period 1 + publicly funded local radiotherapy at no cost to user). In total, 574 cases met eligibility criteria. BCT declined with increasing distance to publicly funded radiotherapy (P = 0.035). BCT rates for periods 1, 2 and 3 were 63% (113/180), 61% (105/173) and 71% (156/221). There were no statistically significant differences in BCT between periods 1 and 2 in the whole cohort or within age, histology or tumour size subgroups. Overall, there was a 9% increase in BCT in the whole cohort in period 3 compared with periods 1 and 2 (P = 0.031). This increase was statistically significant for women over 70 years (19% increase, P = 0.034), for women with ductal carcinoma in situ (25% increase, P = 0.013) and for women with primary tumours that were ≤10 mm (21% increase, P = 0.016). Improving the affordability of radiotherapy through publicly funded transport and radiotherapy at out of area facilities did not improve BCT uptake in a region where radiotherapy was locally available, albeit at cost to the user. Improving both affordability and convenience through the provision of local publicly funded radiotherapy increased BCT

  13. Special cases for proton beam radiotherapy: re-irradiation, lymphoma, and breast cancer.

    PubMed

    Plastaras, John P; Berman, Abigail T; Freedman, Gary M

    2014-12-01

    The dose distributions that can be achieved with protons are usually superior to those of conventional photon external-beam radiation. There are special cases where proton therapy may offer a substantial potential benefit compared to photon treatments where toxicity concerns dominate. Re-irradiation may theoretically be made safer with proton therapy due to lower cumulative lifetime doses to sensitive tissues, such as the spinal cord. Proton therapy has been used in a limited number of patients with rectal, pancreatic, esophageal, and lung cancers. Chordomas and soft tissue sarcomas require particularly high radiation doses, posing additional challenges for re-irradiation. Lymphoma is another special case where proton therapy may be advantageous. Late toxicities from even relatively low radiation doses, including cardiac complications and second cancers, are of concern in lymphoma patients with high cure rates and long life expectancies. Proton therapy has begun to be used for consolidation after chemotherapy in patients with Hodgkin and non-Hodgkin lymphoma. Breast cancer is another emerging area of proton therapy development and use. Proton therapy may offer advantages compared to other techniques in the setting of breast boosts, accelerated partial breast irradiation, and post-mastectomy radiotherapy. In these settings, proton therapy may decrease toxicity associated with breast radiotherapy. As techniques are refined in proton therapy, we may be able to improve the therapeutic ratio by maintaining the benefits of radiotherapy while better minimizing the risks. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Dosimetric characteristics of fabricated silica fibre for postal radiotherapy dose audits

    NASA Astrophysics Data System (ADS)

    Fadzil, M. S. Ahmad; Ramli, N. N. H.; Jusoh, M. A.; Kadni, T.; Bradley, D. A.; Ung, N. M.; Suhairul, H.; Mohd Noor, N.

    2014-11-01

    Present investigation aims to establish the dosimetric characteristics of a novel fabricated flat fibre TLD system for postal radiotherapy dose audits. Various thermoluminescence (TL) properties have been investigated for five sizes of 6 mol% Ge-doped optical fibres. Key dosimetric characteristics including reproducibility, linearity, fading and energy dependence have been established. Irradiations were carried out using a linear accelerator (linac) and a Cobalt-60 machine. For doses from 0.5 Gy up to 10 Gy, Ge-doped flat fibres exhibit linearity between TL yield and dose, reproducible to better than 8% standard deviation (SD) following repeat measurements (n = 3). For photons generated at potentials from 1.25 MeV to 10 MV an energy-dependent response is noted, with a coefficient of variation (CV) of less than 40% over the range of energies investigated. For 6.0 mm length flat fibres 100 μm thick × 350 pm wide, the TL fading loss following 30 days of storage at room temperature was < 8%. The Ge-doped flat fibre system represents a viable basis for use in postal radiotherapy dose audits, corrections being made for the various factors influencing the TL yield.

  15. A software tool of digital tomosynthesis application for patient positioning in radiotherapy.

    PubMed

    Yan, Hui; Dai, Jian-Rong

    2016-03-08

    Digital Tomosynthesis (DTS) is an image modality in reconstructing tomographic images from two-dimensional kV projections covering a narrow scan angles. Comparing with conventional cone-beam CT (CBCT), it requires less time and radiation dose in data acquisition. It is feasible to apply this technique in patient positioning in radiotherapy. To facilitate its clinical application, a software tool was developed and the reconstruction processes were accelerated by graphic process-ing unit (GPU). Two reconstruction and two registration processes are required for DTS application which is different from conventional CBCT application which requires one image reconstruction process and one image registration process. The reconstruction stage consists of productions of two types of DTS. One type of DTS is reconstructed from cone-beam (CB) projections covering a narrow scan angle and is named onboard DTS (ODTS), which represents the real patient position in treatment room. Another type of DTS is reconstructed from digitally reconstructed radiography (DRR) and is named reference DTS (RDTS), which represents the ideal patient position in treatment room. Prior to the reconstruction of RDTS, The DRRs are reconstructed from planning CT using the same acquisition setting of CB projections. The registration stage consists of two matching processes between ODTS and RDTS. The target shift in lateral and longitudinal axes are obtained from the matching between ODTS and RDTS in coronal view, while the target shift in longitudinal and vertical axes are obtained from the matching between ODTS and RDTS in sagittal view. In this software, both DRR and DTS reconstruction algorithms were implemented on GPU environments for acceleration purpose. The comprehensive evaluation of this software tool was performed including geometric accuracy, image quality, registration accuracy, and reconstruction efficiency. The average correlation coefficient between DRR/DTS generated by GPU-based algorithm

  16. A software tool of digital tomosynthesis application for patient positioning in radiotherapy

    PubMed Central

    Dai, Jian‐Rong

    2016-01-01

    Digital Tomosynthesis (DTS) is an image modality in reconstructing tomographic images from two‐dimensional kV projections covering a narrow scan angles. Comparing with conventional cone‐beam CT (CBCT), it requires less time and radiation dose in data acquisition. It is feasible to apply this technique in patient positioning in radiotherapy. To facilitate its clinical application, a software tool was developed and the reconstruction processes were accelerated by graphic processing unit (GPU). Two reconstruction and two registration processes are required for DTS application which is different from conventional CBCT application which requires one image reconstruction process and one image registration process. The reconstruction stage consists of productions of two types of DTS. One type of DTS is reconstructed from cone‐beam (CB) projections covering a narrow scan angle and is named onboard DTS (ODTS), which represents the real patient position in treatment room. Another type of DTS is reconstructed from digitally reconstructed radiography (DRR) and is named reference DTS (RDTS), which represents the ideal patient position in treatment room. Prior to the reconstruction of RDTS, The DRRs are reconstructed from planning CT using the same acquisition setting of CB projections. The registration stage consists of two matching processes between ODTS and RDTS. The target shift in lateral and longitudinal axes are obtained from the matching between ODTS and RDTS in coronal view, while the target shift in longitudinal and vertical axes are obtained from the matching between ODTS and RDTS in sagittal view. In this software, both DRR and DTS reconstruction algorithms were implemented on GPU environments for acceleration purpose. The comprehensive evaluation of this software tool was performed including geometric accuracy, image quality, registration accuracy, and reconstruction efficiency. The average correlation coefficient between DRR/DTS generated by GPU

  17. Clinical Study on Lobaplatin Combined with 5-Fu and Concurrent Radiotherapy in Treating Patients with Inoperable Esophageal Cancer.

    PubMed

    Jia, Xiao-Jing; Huang, Jing-Zi

    2015-01-01

    To investigate short- and long-term treatment effects and side reactions of lobaplatin plus 5-Fu combined and concurrent radiotherapy in treating patients with inoperable middle-advanced stage esophageal cancer. Sixty patients with middle-advanced stage esophageal squamous cell cancer were retrospectively analyzed. All patients were administered lobaplatin (50 mg intravenously) for 2 h on day 1, and 5-Fu (500 mg/m2) injected intravenously from day 1 to 5 for 1 cycle, in an interval of 21 days for totally 4 cycles. At the same time, late-course accelerated hyperfractionated three-dimensional conformal radiotherapy was performed. Patients were firstly treated with conventional fractionated irradiation (1.8 Gy/d, 5 times/week, a total of 23 treatments, and DT41.4 Gy), and then treated with accelerated hyperfractionated irradiation (1.5 Gy, 2 times/d, a total of 27 Gy in 9 days, an entire course of 6-7 weeks, and DT 68.4 Gy). All patients completed treatment, including 10 complete response (CR), 41 partial response (PR), 7 stable disease (SD), and 2 progressive disease (PD). The total effective rate was 85.0% (51/60). Thirty-nine patients had an increased KPS score. One-, 2-, and 3-year survival rates were 85.3%, 57.5%, and 41.7%, respectively. The median survival time was 27 months. The adverse reactions included myelosuppression, which was mainly degreeI and II. The occurrence rate of radiation esophagitis was 17.5%. No significant hepatic or renal toxicity was observed. Lobaplatin plus 5-Fu combined with concurrent radiotherapy is safe and effective in treating patients with middle-advanced stage esophageal cancer. However, this result warrants further evaluation by randomized clinical studies.

  18. The launch of the first UK charity devoted to radiotherapy: ACORRN -- Action Radiotherapy.

    PubMed

    Price, P

    2011-01-01

    The Academic Clinical Oncology and Radiobiology Research Network (ACORRN) was set up to support research and development in radiotherapy in the UK. This innovative networking initiative was launched initially by the National Cancer Research Institute in 2005 to harness the power of the radiation research base in the UK. Through an interactive website a co-ordinated network of multidisciplinary radiation researchers has been established. The network has developed to a stage where it can be self-funding and dedicated to improving radiotherapy for cancer. A patient interactive section and extended support for service development will ensure that anyone treated in the UK will have immediate access to the best knowledge in the country. This provides a solution for cost-effectiveness and future improvement of cancer care and is seen as a new model to support healthcare development and delivery. The charity ACORRN - Action Radiotherapy aims to support radiotherapy research and development and was launched in the House of Lords in July 2010.

  19. Ionizing radiation-induced acoustics for radiotherapy and diagnostic radiology applications.

    PubMed

    Hickling, Susannah; Xiang, Liangzhong; Jones, Kevin C; Parodi, Katia; Assmann, Walter; Avery, Stephen; Hobson, Maritza; El Naqa, Issam

    2018-04-21

    Acoustic waves are induced via the thermoacoustic effect in objects exposed to a pulsed beam of ionizing radiation. This phenomenon has interesting potential applications in both radiotherapy dosimetry and treatment guidance as well as low dose radiological imaging. After initial work in the field in the 1980s and early 1990s, little research was done until 2013 when interest was rejuvenated, spurred on by technological advances in ultrasound transducers and the increasing complexity of radiotherapy delivery systems. Since then, many studies have been conducted and published applying ionizing radiation-induced acoustic principles into three primary research areas: Linear accelerator photon beam dosimetry, proton therapy range verification, and radiological imaging. This review article introduces the theoretical background behind ionizing radiation-induced acoustic waves, summarizes recent advances in the field, and provides an outlook on how the detection of ionizing radiation-induced acoustic waves can be used for relative and in vivo dosimetry in photon therapy, localization of the Bragg peak in proton therapy, and as a low-dose medical imaging modality. Future prospects and challenges for clinical implementation of these techniques are discussed. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Expanding global access to radiotherapy.

    PubMed

    Atun, Rifat; Jaffray, David A; Barton, Michael B; Bray, Freddie; Baumann, Michael; Vikram, Bhadrasain; Hanna, Timothy P; Knaul, Felicia M; Lievens, Yolande; Lui, Tracey Y M; Milosevic, Michael; O'Sullivan, Brian; Rodin, Danielle L; Rosenblatt, Eduardo; Van Dyk, Jacob; Yap, Mei Ling; Zubizarreta, Eduardo; Gospodarowicz, Mary

    2015-09-01

    Radiotherapy is a critical and inseparable component of comprehensive cancer treatment and care. For many of the most common cancers in low-income and middle-income countries, radiotherapy is essential for effective treatment. In high-income countries, radiotherapy is used in more than half of all cases of cancer to cure localised disease, palliate symptoms, and control disease in incurable cancers. Yet, in planning and building treatment capacity for cancer, radiotherapy is frequently the last resource to be considered. Consequently, worldwide access to radiotherapy is unacceptably low. We present a new body of evidence that quantifies the worldwide coverage of radiotherapy services by country. We show the shortfall in access to radiotherapy by country and globally for 2015-35 based on current and projected need, and show substantial health and economic benefits to investing in radiotherapy. The cost of scaling up radiotherapy in the nominal model in 2015-35 is US$26·6 billion in low-income countries, $62·6 billion in lower-middle-income countries, and $94·8 billion in upper-middle-income countries, which amounts to $184·0 billion across all low-income and middle-income countries. In the efficiency model the costs were lower: $14·1 billion in low-income, $33·3 billion in lower-middle-income, and $49·4 billion in upper-middle-income countries-a total of $96·8 billion. Scale-up of radiotherapy capacity in 2015-35 from current levels could lead to saving of 26·9 million life-years in low-income and middle-income countries over the lifetime of the patients who received treatment. The economic benefits of investment in radiotherapy are very substantial. Using the nominal cost model could produce a net benefit of $278·1 billion in 2015-35 ($265·2 million in low-income countries, $38·5 billion in lower-middle-income countries, and $239·3 billion in upper-middle-income countries). Investment in the efficiency model would produce in the same period an even

  1. Fractionated stereotactic radiotherapy boost for gynecologic tumors: An alternative to brachytherapy?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Molla, Meritxell; Escude, Lluis D.; Nouet, Philippe

    2005-05-01

    Purpose: A brachytherapy (BT) boost to the vaginal vault is considered standard treatment for many endometrial or cervical cancers. We aimed to challenge this treatment standard by using stereotactic radiotherapy (SRT) with a linac-based micromultileaf collimator technique. Methods and Materials: Since January 2002, 16 patients with either endometrial (9) or cervical (7) cancer have been treated with a final boost to the areas at higher risk for relapse. In 14 patients, the target volume included the vaginal vault, the upper vagina, the parametria, or (if not operated) the uterus (clinical target volume [CTV]). In 2 patients with local relapse, themore » CTV was the tumor in the vaginal stump. Margins of 6-10 mm were added to the CTV to define the planning target volume (PTV). Hypofractionated dynamic-arc or intensity-modulated radiotherapy techniques were used. Postoperative treatment was delivered in 12 patients (2 x 7 Gy to the PTV with a 4-7-day interval between fractions). In the 4 nonoperated patients, a dose of 4 Gy/fraction in 5 fractions with 2 to 3 days' interval was delivered. Patients were immobilized in a customized vacuum body cast and optimally repositioned with an infrared-guided system developed for extracranial SRT. To further optimize daily repositioning and target immobilization, an inflated rectal balloon was used during each treatment fraction. In 10 patients, CT resimulation was performed before the last boost fraction to assess for repositioning reproducibility via CT-to-CT registration and to estimate PTV safety margins around the CTV. Finally, a comparative treatment planning study between BT and SRT was performed in 2 patients with an operated endometrial Stage I cancer. Results: No patient developed severe acute urinary or low-intestinal toxicity. No patient developed urinary late effects (>6 months). One patient with a vaginal relapse previously irradiated to the pelvic region presented with Grade 3 rectal bleeding 18 months after

  2. Radiotherapy for gastric lymphoma: a planning study of 3D conformal radiotherapy, the half-beam method, and intensity-modulated radiotherapy.

    PubMed

    Inaba, Koji; Okamoto, Hiroyuki; Wakita, Akihisa; Nakamura, Satoshi; Kobayashi, Kazuma; Harada, Ken; Kitaguchi, Mayuka; Sekii, Shuhei; Takahashi, Kana; Yoshio, Kotaro; Murakami, Naoya; Morota, Madoka; Ito, Yoshinori; Sumi, Minako; Uno, Takashi; Itami, Jun

    2014-11-01

    During radiotherapy for gastric lymphoma, it is difficult to protect the liver and kidneys in cases where there is considerable overlap between these organs and the target volume. This study was conducted to compare the three radiotherapy planning techniques of four-fields 3D conformal radiotherapy (3DCRT), half-field radiotherapy (the half-beam method) and intensity-modulated radiotherapy (IMRT) used to treat primary gastric lymphoma in which the planning target volume (PTV) had a large overlap with the left kidney. A total of 17 patients with gastric diffuse large B-cell lymphoma (DLBCL) were included. In DLBCL, immunochemotherapy (Rituximab + CHOP) was followed by radiotherapy of 40 Gy to the whole stomach and peri-gastric lymph nodes. 3DCRT, the half-field method, and IMRT were compared with respect to the dose-volume histogram (DVH) parameters and generalized equivalent uniform dose (gEUD) to the kidneys, liver and PTV. The mean dose and gEUD for 3DCRT was higher than for IMRT and the half-beam method in the left kidney and both kidneys. The mean dose and gEUD of the left kidney was 2117 cGy and 2224 cGy for 3DCRT, 1520 cGy and 1637 cGy for IMRT, and 1100 cGy and 1357 cGy for the half-beam method, respectively. The mean dose and gEUD of both kidneys was 1335 cGy and 1559 cGy for 3DCRT, 1184 cGy and 1311 cGy for IMRT, and 700 cGy and 937 cGy for the half-beam method, respectively. Dose-volume histograms (DVHs) of the liver revealed a larger volume was irradiated in the dose range <25 Gy with 3DCRT, while the half-beam method irradiated a larger volume of liver with the higher dose range (>25 Gy). IMRT and the half-beam method had the advantages of dose reduction for the kidneys and liver. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  3. Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy.

    PubMed

    Zelyak, O; Fallone, B G; St-Aubin, J

    2017-12-14

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low-density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  4. Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy

    NASA Astrophysics Data System (ADS)

    Zelyak, O.; Fallone, B. G.; St-Aubin, J.

    2018-01-01

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low-density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  5. Randomized Phase III Noninferiority Study Comparing Two Radiotherapy Fractionation Schedules in Patients With Low-Risk Prostate Cancer

    PubMed Central

    Dignam, James J.; Amin, Mahul B.; Bruner, Deborah W.; Low, Daniel; Swanson, Gregory P.; Shah, Amit B.; D’Souza, David P.; Michalski, Jeff M.; Dayes, Ian S.; Seaward, Samantha A.; Hall, William A.; Nguyen, Paul L.; Pisansky, Thomas M.; Faria, Sergio L.; Chen, Yuhchyau; Koontz, Bridget F.; Paulus, Rebecca; Sandler, Howard M.

    2016-01-01

    Purpose Conventional radiotherapy (C-RT) treatment schedules for patients with prostate cancer typically require 40 to 45 treatments that take place from > 8 to 9 weeks. Preclinical and clinical research suggest that hypofractionation—fewer treatments but at a higher dose per treatment—may produce similar outcomes. This trial was designed to assess whether the efficacy of a hypofractionated radiotherapy (H-RT) treatment schedule is no worse than a C-RT schedule in men with low-risk prostate cancer. Patients and Methods A total of 1,115 men with low-risk prostate cancer were randomly assigned 1:1 to C-RT (73.8 Gy in 41 fractions over 8.2 weeks) or to H-RT (70 Gy in 28 fractions over 5.6 weeks). This trial was designed to establish (with 90% power and an α of .05) that treatment with H-RT results in 5-year disease-free survival (DFS) that is not worse than C-RT by more than 7.65% (H-RT/C-RT hazard ratio [HR] < 1.52). Results A total of 1,092 men were protocol eligible and had follow-up information; 542 patients were assigned to C-RT and 550 to H-RT. Median follow-up was 5.8 years. Baseline characteristics were not different according to treatment assignment. The estimated 5-year DFS was 85.3% (95% CI, 81.9 to 88.1) in the C-RT arm and 86.3% (95% CI, 83.1 to 89.0) in the H-RT arm. The DFS HR was 0.85 (95% CI, 0.64 to 1.14), and the predefined noninferiority criterion that required that DFS outcomes be consistent with HR < 1.52 was met (P < .001). Late grade 2 and 3 GI and genitourinary adverse events were increased (HR, 1.31 to 1.59) in patients who were treated with H-RT. Conclusion In men with low-risk prostate cancer, the efficacy of 70 Gy in 28 fractions over 5.6 weeks is not inferior to 73.8 Gy in 41 fractions over 8.2 weeks, although an increase in late GI/genitourinary adverse events was observed in patients treated with H-RT. PMID:27044935

  6. Cardiac Side-effects From Breast Cancer Radiotherapy.

    PubMed

    Taylor, C W; Kirby, A M

    2015-11-01

    Breast cancer radiotherapy reduces the risk of cancer recurrence and death. However, it usually involves some radiation exposure of the heart and analyses of randomised trials have shown that it can increase the risk of heart disease. Estimates of the absolute risks of radiation-related heart disease are needed to help oncologists plan each individual woman's treatment. The risk for an individual woman varies according to her estimated cardiac radiation dose and her background risk of ischaemic heart disease in the absence of radiotherapy. When it is known, this risk can then be compared with the absolute benefit of the radiotherapy. At present, many UK cancer centres are already giving radiotherapy with mean heart doses of less than 3 Gy and for most women the benefits of the radiotherapy will probably far outweigh the risks. Technical approaches to minimising heart dose in breast cancer radiotherapy include optimisation of beam angles, use of multileaf collimator shielding, intensity-modulated radiotherapy, treatment in a prone position, treatment in deep inspiration (including the use of breath-hold and gating techniques), proton therapy and partial breast irradiation. The multileaf collimator is suitable for many women with upper pole left breast cancers, but for women with central or lower pole cancers, breath-holding techniques are now recommended in national UK guidelines. Ongoing work aims to identify ways of irradiating pan-regional lymph nodes that are effective, involve minimal exposure of organs at risk and are feasible to plan, deliver and verify. These will probably include wide tangent-based field-in-field intensity-modulated radiotherapy or arc radiotherapy techniques in combination with deep inspiratory breath-hold, and proton beam irradiation for women who have a high predicted heart dose from intensity-modulated radiotherapy. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  7. Combined chemo-radiotherapy in locally advanced nasopharyngeal carcinomas.

    PubMed

    Perri, Francesco; Della Vittoria Scarpati, Giuseppina; Buonerba, Carlo; Di Lorenzo, Giuseppe; Longo, Francesco; Muto, Paolo; Schiavone, Concetta; Sandomenico, Fabio; Caponigro, Francesco

    2013-05-10

    To provide efficacy and safety data about the combined use of radiotherapy and chemo-radiotherapy in nasopharyngeal carcinoma (NPC). We reviewed data of 40 patients with locally advanced NPC treated with induction chemotherapy followed by concomitant chemo-radiotherapy (CCRT) (22/40 patients) or CCRT alone (18/40) from March 2006 to March 2012. Patients underwent fiberoscopy with biopsy of the primitive tumor, and computed tomography scan of head, neck, chest and abdomen with and without contrast. Cisplatin was used both as induction and as concomitant chemotherapy, while 3D conformal radiation therapy was delivered to the nasopharynx and relevant anatomic regions (total dose, 70 Gy). The treatment was performed using 6 MV photons of the linear accelerator administered in 2 Gy daily fraction for five days weekly. This retrospective analysis was approved by the review boards of the participating institutions. Patients gave their consent to treatment and to anonymous analysis of clinical data. Thirty-three patients were males and 7 were females. Median follow-up time was 58 mo (range, 1-92 mo). In the sub-group of twenty patients with a follow-up time longer than 36 mo, the 3-year survival and disease free survival rates were 85% and 75%, respectively. Overall response rate both in patients treated with induction chemotherapy followed by CCRT and in those treated with CCRT alone was 100%. Grade 3 neutropenia was the most frequent acute side-effect and it occurred in 20 patients. Grade 2 mucositis was seen in 29 patients, while grade 2 xerostomia was seen in 30 patients. Overall toxicity was manageable and it did not cause any significant treatment delay. In the whole sample population, long term toxicity included grade 2 xerostomia in 22 patients, grade 1 dysgeusia in 17 patients and grade 1 subcutaneous fibrosis in 30 patients. Both CCRT and induction chemotherapy followed by CCRT showed excellent activity in locally advanced NPC. The role of adjuvant chemotherapy

  8. Magnetic Resonance Imaging-Guided Adaptive Radiation Therapy: A "Game Changer" for Prostate Treatment?

    PubMed

    Pathmanathan, Angela U; van As, Nicholas J; Kerkmeijer, Linda G W; Christodouleas, John; Lawton, Colleen A F; Vesprini, Danny; van der Heide, Uulke A; Frank, Steven J; Nill, Simeon; Oelfke, Uwe; van Herk, Marcel; Li, X Allen; Mittauer, Kathryn; Ritter, Mark; Choudhury, Ananya; Tree, Alison C

    2018-02-01

    Radiation therapy to the prostate involves increasingly sophisticated delivery techniques and changing fractionation schedules. With a low estimated α/β ratio, a larger dose per fraction would be beneficial, with moderate fractionation schedules rapidly becoming a standard of care. The integration of a magnetic resonance imaging (MRI) scanner and linear accelerator allows for accurate soft tissue tracking with the capacity to replan for the anatomy of the day. Extreme hypofractionation schedules become a possibility using the potentially automated steps of autosegmentation, MRI-only workflow, and real-time adaptive planning. The present report reviews the steps involved in hypofractionated adaptive MRI-guided prostate radiation therapy and addresses the challenges for implementation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  9. The role of intraoperative radiotherapy in solid tumors.

    PubMed

    Skandarajah, A R; Lynch, A C; Mackay, J R; Ngan, S; Heriot, A G

    2009-03-01

    Combined multimodality therapy is becoming standard treatment for many solid tumors, but the role of intraoperative radiotherapy in the management of solid tumors remains uncertain. The aim is to review the indication, application, and outcomes of intraoperative radiotherapy in the management of nongynecological solid tumors. A literature search was performed using Medline, Embase, Ovid, and Cochrane database for studies between 1965 and 2008 assessing intraoperative radiotherapy, using the keywords "intraoperative radiotherapy," "colorectal cancer," "breast cancer," "gastric cancer," "pancreatic cancer," "soft tissue tumor," and "surgery." Only publications in English with available abstracts and regarding adult humans were included, and the evidence was critically evaluated. Our search retrieved 864 publications. After exclusion of nonclinical papers, duplicated papers and exclusion of brachytherapy papers, 77 papers were suitable to assess the current role of intraoperative radiotherapy. The clinical application and evidence base of intraoperative radiotherapy for each cancer is presented. Current studies in all common cancers show an additional benefit in local recurrence rates when intraoperative radiotherapy is included in the multimodal treatment. However, intraoperative radiotherapy may not improve overall survival and has significant morbidity depending on the site of the tumor. Intraoperative radiotherapy does have a role in the multidisciplinary management of solid tumors, but further studies are required to more precisely determine the extent of benefit.

  10. Genome-wide transcription responses to synchrotron microbeam radiotherapy.

    PubMed

    Sprung, Carl N; Yang, Yuqing; Forrester, Helen B; Li, Jason; Zaitseva, Marina; Cann, Leonie; Restall, Tina; Anderson, Robin L; Crosbie, Jeffrey C; Rogers, Peter A W

    2012-10-01

    The majority of cancer patients achieve benefit from radiotherapy. A significant limitation of radiotherapy is its relatively low therapeutic index, defined as the maximum radiation dose that causes acceptable normal tissue damage to the minimum dose required to achieve tumor control. Recently, a new radiotherapy modality using synchrotron-generated X-ray microbeam radiotherapy has been demonstrated in animal models to ablate tumors with concurrent sparing of normal tissue. Very little work has been undertaken into the cellular and molecular mechanisms that differentiate microbeam radiotherapy from broad beam. The purpose of this study was to investigate and compare the whole genome transcriptional response of in vivo microbeam radiotherapy versus broad beam irradiated tumors. We hypothesized that gene expression changes after microbeam radiotherapy are different from those seen after broad beam. We found that in EMT6.5 tumors at 4-48 h postirradiation, microbeam radiotherapy differentially regulates a number of genes, including major histocompatibility complex (MHC) class II antigen gene family members, and other immunity-related genes including Ciita, Ifng, Cxcl1, Cxcl9, Indo and Ubd when compared to broad beam. Our findings demonstrate molecular differences in the tumor response to microbeam versus broad beam irradiation and these differences provide insight into the underlying mechanisms of microbeam radiotherapy and broad beam.

  11. Palliative radiotherapy practice within Western European countries: impact of the radiotherapy financing system?

    PubMed

    Lievens, Y; Van den Bogaert, W; Rijnders, A; Kutcher, G; Kesteloot, K

    2000-09-01

    To analyze the reimbursement modalities for radiotherapy in the different Western European countries, as well as to investigate if these differences have an impact on the palliative radiotherapy practice for bone metastases. A questionnaire was sent to 565 radiotherapy centres included in the 1997 ESTRO directory. In this questionnaire the reimbursement strategy applied in the different centres was assessed, with respect to the use of a budget (departmental or hospital budget), case payment and/or fee-for-service reimbursement. The differences were analyzed according to country and to type and size of the radiotherapy centre. A total of 170 centres (86% of the responders) returned the questionnaire. Most frequent is budget reimbursement: some form of budget reimbursement is found in 69% of the centres, whereas 46% of the centres are partly reimbursed through fee-for-service and 35% through case payment. The larger the department, the more frequent the reimbursement through a budget or a case payment system and the less the importance of fee-for-service reimbursement (chi(2): P=0.0012; logit: P=0.0055). Whereas private centres are almost equally reimbursed by fee-for-service financing as by budget or case payment, radiotherapy departments in university hospitals receive the largest part of their financial resources through a budget or by case payment (83%) (chi(2): P=0.002; logit: P=0.0073). A correlation between the country and the radiotherapy reimbursement system was also demonstrated (P=0.002), radiotherapy centres in Spain, the Netherlands and the United Kingdom being almost entirely reimbursed through a budget and/or case payment and centres in Germany and Switzerland mostly through a fee-for-service system. In budget and case payment financing lower total number of fractions and lower total dose (chi(2): P=0.003; logit: P=0.0120) as well as less shielding blocks (chi(2): P=0.003; logit: P=0.0066) are used. A same tendency is found for the use of isodose

  12. Time-driven activity-based cost comparison of prostate cancer brachytherapy and intensity-modulated radiation therapy.

    PubMed

    Dutta, Sunil W; Bauer-Nilsen, Kristine; Sanders, Jason C; Trifiletti, Daniel M; Libby, Bruce; Lash, Donna H; Lain, Melody; Christodoulou, Deborah; Hodge, Constance; Showalter, Timothy N

    To evaluate the delivery cost of frequently used radiotherapy options offered to patients with intermediate- to high-risk prostate cancer using time-driven activity-based costing and compare the results with Medicare reimbursement and relative value units (RVUs). Process maps were created to represent each step of prostate radiotherapy treatment at our institution. Salary data, equipment purchase costs, and consumable costs were factored into the cost analysis. The capacity cost rate was determined for each resource and calculated for each treatment option from initial consultation to its completion. Treatment options included low-dose-rate brachytherapy (LDR-BT), combined high-dose-rate brachytherapy single fraction boost with 25-fraction intensity-modulated radiotherapy (HDR-BT-IMRT), moderately hypofractionated 28-fraction IMRT, conventionally fractionated 39-fraction IMRT, and conventionally fractionated (2 Gy/fraction) 23-fraction pelvis irradiation with 16-fraction prostate boost. The total cost to deliver LDR-BT, HDR-BT-IMRT, moderately hypofractionated 28-fraction IMRT, conventionally fractionated 39-fraction IMRT, conventionally fractionated 39-fraction IMRT, and conventionally fractionated (2 Gy/fraction) 23-fraction pelvis irradiation with 16-fraction prostate boost was $2719, $6517, $4173, $5507, and $5663, respectively. Total reimbursement for each course was $3123, $10,156, $7862, $9725, and $10,377, respectively. Radiation oncology attending time was 1.5-2 times higher for treatment courses incorporating BT. Attending radiation oncologist's time consumed per RVU was higher with BT (4.83 and 2.56 minutes per RVU generated for LDR-BT and HDR-BT-IMRT, respectively) compared to without BT (1.41-1.62 minutes per RVU). Time-driven activity-based costing analysis identified higher delivery costs associated with prostate BT compared with IMRT alone. In light of recent guidelines promoting BT for intermediate- to high-risk disease, re-evaluation of payment

  13. Estimating radiotherapy demands in South East Asia countries in 2025 and 2035 using evidence-based optimal radiotherapy fractions.

    PubMed

    Yahya, Noorazrul; Roslan, Nurhaziqah

    2018-01-08

    As about 50% of cancer patients may require radiotherapy, the demand of radiotherapy as the main treatment to treat cancer is likely to rise due to rising cancer incidence. This study aims to quantify the radiotherapy demand in countries in Southeast Asia (SEA) in 2025 and 2035 using evidence-based optimal radiotherapy fractions. SEA country-specific cancer incidence by tumor site for 2015, 2025 and 2035 was extracted from the GLOBOCAN database. We utilized the optimal radiotherapy utilization rate model by Wong et al. (2016) to calculate the optimal number of fractions for all tumor sites in each SEA country. The available machines (LINAC & Co-60) were extracted from the IAEA's Directory of Radiotherapy Centres (DIRAC) from which the number of available fractions was calculated. The incidence of cancers in SEA countries are expected to be 1.1 mil cases (2025) and 1.4 mil (2035) compared to 0.9 mil (2015). The number of radiotherapy fractions needed in 2025 and 2035 are 11.1 and 14.1 mil, respectively, compared to 7.6 mil in 2015. In 2015, the radiotherapy fulfillment rate (RFR; required fractions/available fractions) varied between countries with Brunei, Singapore and Malaysia are highest (RFR > 1.0 - available fractions > required fractions), whereas Cambodia, Indonesia, Laos, Myanmar, Philippines, Timor-Leste and Vietnam have RFR < 0.5. RFR is correlated to GDP per capita (ρ = 0.73, P = 0.01). To allow RFR ≥1 in 2025 and 2035, another 866 and 1177 machines are required, respectively. The number are lower if longer running hours are implemented. With the optimal number of radiotherapy fractions, estimation for number of machines required can be obtained which will guide acquisition of machines in SEA countries. RFR is low with access varied based on the economic status. © 2018 John Wiley & Sons Australia, Ltd.

  14. A unique hypofractionated radiotherapy schedule with 51.3 Gy in 18 fractions three times per week for early breast cancer: outcomes including local control, acute and late skin toxicity.

    PubMed

    Vassilis, Kouloulias; Ioannis, Gogalis; Anna, Zygogianni; Christina, Armpilia; Christos, Antypas; John, Kokakis; Porfyrios, Koromperlis; Vassiliki, Gennimata; John, Kouvaris

    2017-03-01

    Evaluation of local control and acute and late toxicity regarding a hypofractionated RT schedule for breast cancer patients. Between October 2007 and October 2009, 80 women with early breast cancer were treated by 42.75 Gy in 15 fractions over 5 weeks. This treatment involved three fractions per week (Monday-Wednesday-Friday). All patients received an additional boost dose to the tumor bed of 8.55 Gy in 3 fractions using 6 MV photons. The primary endpoint included any local recurrence in the treated breast. Secondary endpoint included acute and late radiation skin toxicity. The median follow-up time was 63 months (range 60-72). Radiation toxicity was graded according the RTOG/EORTC criteria. Neither local nor distant recurrence was noted in any patient during this 3-year follow-up. Grade 0, 1, 2 acute skin toxicity was observed in 56/80 (70.0 %), in 19/80 (23.8 %) and in 5/80 (6.3 %), respectively. Three months post-RT, toxicity grades 0, 1, 2 skin toxicity were 64/80 (80 %), 14/80 (17.5 %) and 2/80 (2.5 %), respectively. Late toxicity as grade 0, 1 was observed in 72/80 (90.0 %) and in 8/80 (10.0 %), respectively, 6 months post-RT, whereas after 1 year they were 78/80 (97.5 %) and 2/80 (2.5 %), respectively. Preliminary results regarding skin reactions, cosmetic appearance and local control are consistent with published data that support the use of shorter fractionation schedules in early breast cancer patients after breast conservative surgery. Longer follow-up and a randomized prospective study stand in need for the extraction of safe conclusions.

  15. Short-Course Hypofractionated Radiation Therapy With Boost in Women With Stages 0 to IIIa Breast Cancer: A Phase 2 Trial.

    PubMed

    Ahlawat, Stuti; Haffty, Bruce G; Goyal, Sharad; Kearney, Thomas; Kirstein, Laurie; Chen, Chunxia; Moore, Dirk F; Khan, Atif J

    2016-01-01

    Conventionally fractionated whole-breast irradiation (WBI) with a boost takes approximately 6 to 7 weeks. We evaluated a short course of hypofractionated (HF), accelerated WBI in which therapy was completed in 3 weeks inclusive of a sequential boost. We delivered a whole-breast dose of 36.63 Gy in 11 fractions of 3.33 Gy over 11 days, followed by a lumpectomy bed boost in 4 fractions of 3.33 Gy delivered once daily for a total of 15 treatment days. Acute toxicities were scored using Common Terminology Criteria for Adverse Events version 4. Late toxicities were scored using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scale. Cosmesis was scored using the Harvard Cosmesis Scale. Our primary endpoint was freedom from locoregional failure; we incorporated early stopping criteria based on predefined toxicity thresholds. Cosmesis was examined as a secondary endpoint. We enrolled 83 women with stages 0 to IIIa breast cancer. After a median follow-up of 40 months, 2 cases of isolated ipsilateral breast tumor recurrence occurred (2 of 83; crude rate, 2.4%). Three-year estimated local recurrence-free survival was 95.9% (95% confidence interval [CI]: 87.8%-98.7%). The 3-year estimated distant recurrence-free survival was 97.3% (95% CI: 89.8%-99.3%). Three-year secondary malignancy-free survival was 94.3% (95% CI: 85.3%-97.8%). Twenty-nine patients (34%) had grade 2 acute toxicity, and 1 patient had a late grade 2 toxicity (fibrosis). One patient had acute grade 3 dermatitis, whereas 2 patients experienced grade 3 late skin toxicity. Ninety-four percent of evaluable patients had good or excellent cosmesis. Our phase 2 institutional study offers one of the shortest courses of HF therapy, delivered in 15 fractions inclusive of a sequential boost. We demonstrated expected low toxicity and high local control rates with good to excellent cosmetic outcomes. This fractionation scheme is feasible and well tolerated and offers women

  16. A case study of the neuropsychological outcomes following microsurgery, conventional radiotherapy and stereotactic radiotherapy for an adult's recurrent craniopharyngioma.

    PubMed

    Preece, David; Allan, Alfred; Becerra, Rodrigo

    2016-01-01

    To examine the neuropsychological outcomes for an adult patient, 2 years after receiving microsurgery and conventional radiotherapy for a recurrent craniopharyngioma; and the impact of a further intervention, stereotactic radiotherapy, on this level of neuropsychological functioning. JD, a 30 year old male whose recurrent craniopharyngioma had 2 years earlier been treated with two operations and conventional radiotherapy. JD was assessed (using standardized clinical tests) before and after a course of stereotactic radiotherapy. Prior to stereotactic radiotherapy (and 2 years after microsurgery and conventional radiotherapy) JD's IQ was intact, but considerable impairments were present in executive functioning, memory, theory of mind and processing speed. Fifteen months after stereotactic radiotherapy, all neuropsychological domains remained largely static or improved, supporting the utility of this treatment option in the neuropsychological domain. However, deficits in executive functioning, memory and processing speed remained. These findings suggest that, even after multiple treatments, substantial cognitive impairments can be present in an adult patient with a recurrent craniopharyngioma. This profile of deficits underlines the inadequacy of relying purely on IQ as a marker for cognitive health in this population and emphasizes the need to include neuropsychological impairments as a focus of rehabilitation with these patients.

  17. Can a commercial gel dosimetry system be used to verify stereotactic spinal radiotherapy treatment dose distributions?

    NASA Astrophysics Data System (ADS)

    Kairn, T.; Asena, A.; Crowe, S. B.; Livingstone, A.; Papworth, D.; Smith, S.; Sutherland, B.; Sylvander, S.; Franich, R. D.; Trapp, J. V.

    2017-05-01

    This study investigated the use of the TruView xylenol-orange-based gel and VISTA optical CT scanner (both by Modus Medical Inc, London, Canada), for use in verifying the accuracy of planned dose distributions for hypo-fractionated (stereotactic) vertebral treatments. Gel measurements were carried out using three stereotactic vertebral treatments and compared with planned doses calculated using the Eclipse treatment planning system (Varian Medical Systems, Palo Alto, USA) as well as with film measurements made using Gafchromic EBT3 film (Ashland Inc, Covington, USA), to investigate the accuracy of the gel system. The gel was calibrated with reference to a moderate-dose gradient region in one of the gel samples. Generally, the gel measurements were able to approximate the close agreement between the doses calculated by the treatment planning system and the doses measured using film (which agreed with each other within 2%), despite lower resolution and bit depth. Poorer agreement was observed when the dose delivered to the gel exceeded the range of doses delivered in the calibration region. This commercial gel dosimetry system may be used to verify hypo-fractionated treatments of vertebral targets, although separate gel calibration measurements are recommended.

  18. A Variable Energy CW Compact Accelerator for Ion Cancer Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnstone, Carol J.; Taylor, J.; Edgecock, R.

    2016-03-10

    Cancer is the second-largest cause of death in the U.S. and approximately two-thirds of all cancer patients will receive radiation therapy with the majority of the radiation treatments performed using x-rays produced by electron linacs. Charged particle beam radiation therapy, both protons and light ions, however, offers advantageous physical-dose distributions over conventional photon radiotherapy, and, for particles heavier than protons, a significant biological advantage. Despite recognition of potential advantages, there is almost no research activity in this field in the U.S. due to the lack of clinical accelerator facilities offering light ion therapy in the States. In January, 2013, amore » joint DOE/NCI workshop was convened to address the challenges of light ion therapy [1], inviting more than 60 experts from diverse fields related to radiation therapy. This paper reports on the conclusions of the workshop, then translates the clinical requirements into accelerat or and beam-delivery technical specifications. A comparison of available or feasible accelerator technologies is compared, including a new concept for a compact, CW, and variable energy light ion accelerator currently under development. This new light ion accelerator is based on advances in nonscaling Fixed-Field Alternating gradient (FFAG) accelerator design. The new design concepts combine isochronous orbits with long (up to 4m) straight sections in a compact racetrack format allowing inner circulating orbits to be energy selected for low-loss, CW extraction, effectively eliminating the high-loss energy degrader in conventional CW cyclotron designs.« less

  19. Innovations in Radiotherapy Technology.

    PubMed

    Feain, I J; Court, L; Palta, J R; Beddar, S; Keall, P

    2017-02-01

    Many low- and middle-income countries, together with remote and low socioeconomic populations within high-income countries, lack the resources and services to deal with cancer. The challenges in upgrading or introducing the necessary services are enormous, from screening and diagnosis to radiotherapy planning/treatment and quality assurance. There are severe shortages not only in equipment, but also in the capacity to train, recruit and retain staff as well as in their ongoing professional development via effective international peer-review and collaboration. Here we describe some examples of emerging technology innovations based on real-time software and cloud-based capabilities that have the potential to redress some of these areas. These include: (i) automatic treatment planning to reduce physics staffing shortages, (ii) real-time image-guided adaptive radiotherapy technologies, (iii) fixed-beam radiotherapy treatment units that use patient (rather than gantry) rotation to reduce infrastructure costs and staff-to-patient ratios, (iv) cloud-based infrastructure programmes to facilitate international collaboration and quality assurance and (v) high dose rate mobile cobalt brachytherapy techniques for intraoperative radiotherapy. Copyright © 2016 The Royal College of Radiologists. All rights reserved.

  20. Skyshine photon doses from 6 and 10 MV medical linear accelerators

    PubMed Central

    da Rosa, Luiz A. R.

    2012-01-01

    The skyshine radiation phenomenon consists of the scattering of primary photon beams in the atmosphere above the roof of a medical linear accelerator facility, generating an additional dose at ground level in the vicinity of the treatment room. Thus, with respect to radioprotection, this situation plays an important role when the roof is designed with little shielding and there are buildings next to the radiotherapy treatment room. In literature, there are few reported skyshine‐measured doses and these contain poor agreement with empirical calculations. In this work, we carried out measurements of skyshine photon dose rates produced from eight different 6 and 10 MV medical accelerators. Each measurement was performed outside the room facility, with the beam positioned in the upward direction, at a horizontal distance from the target and for a 40 cm×40 cm maximum photon field size at the accelerator isocenter. Measured dose‐equivalent rates results were compared with calculations obtained by an empirical expression, and differences between them deviated in one or more order of magnitude. PACS numbers: 87.53.‐j, 87.53.Bn PMID:22231219

  1. Derivation of mean dose tolerances for new fractionation schemes and treatment modalities

    NASA Astrophysics Data System (ADS)

    Perkó, Zoltán; Bortfeld, Thomas; Hong, Theodore; Wolfgang, John; Unkelbach, Jan

    2018-02-01

    Avoiding toxicities in radiotherapy requires the knowledge of tolerable organ doses. For new, experimental fractionation schemes (e.g. hypofractionation) these are typically derived from traditional schedules using the biologically effective dose (BED) model. In this report we investigate the difficulties of establishing mean dose tolerances that arise since the mean BED depends on the entire spatial dose distribution, rather than on the dose level alone. A formula has been derived to establish mean physical dose constraints such that they are mean BED equivalent to a reference treatment scheme. This formula constitutes a modified BED equation where the influence of the spatial dose distribution is summarized in a single parameter, the dose shape factor. To quantify effects we analyzed 24 liver cancer patients for whom both proton and photon IMRT treatment plans were available. The results show that the standard BED equation—neglecting the spatial dose distribution—can overestimate mean dose tolerances for hypofractionated treatments by up to 20%. The shape difference between photon and proton dose distributions can cause 30-40% differences in mean physical dose for plans having identical mean BEDs. Converting hypofractionated, 5/15-fraction proton doses to mean BED equivalent photon doses in traditional 35-fraction regimens resulted in up to 10 Gy higher doses than applying the standard BED formula. The dose shape effect should be accounted for to avoid overestimation of mean dose tolerances, particularly when estimating constraints for hypofractionated regimens. Additionally, tolerances established for one treatment modality cannot necessarily be applied to other modalities with drastically different dose distributions, such as proton therapy. Last, protons may only allow marginal (5-10%) dose escalation if a fraction-size adjusted organ mean dose is constraining instead of a physical dose.

  2. Breast Cancer Patients’ Experience of External-Beam Radiotherapy

    PubMed Central

    Schnur, Julie B.; Ouellette, Suzanne C.; Bovbjerg, Dana H.; Montgomery, Guy H.

    2013-01-01

    Radiotherapy is a critical component of treatment for the majority of women with breast cancer, particularly those who receive breast conserving surgery. Although medically beneficial, radiotherapy can take a physical and psychological toll on patients. However, little is known about the specific thoughts and feelings experienced by women undergoing breast cancer radiotherapy. Therefore, the study aim was to use qualitative research methods to develop an understanding of these thoughts and feelings based on 180 diary entries, completed during radiotherapy by 15 women with Stage 0-III breast cancer. Thematic analysis identified four primary participant concerns: (a) a preoccupation with time; (b) fantasies (both optimistic and pessimistic) about life following radiotherapy; (c) the toll their side-effect experience takes on their self-esteem; and (d) feeling mystified by radiotherapy. These themes are consistent with previous literature on illness and identity. These findings have implications for the treatment and care of women undergoing breast cancer radiotherapy. PMID:19380502

  3. On-line estimations of delivered radiation doses in three-dimensional conformal radiotherapy treatments of carcinoma uterine cervix patients in linear accelerator

    PubMed Central

    Putha, Suman Kumar; Saxena, P. U.; Banerjee, S.; Srinivas, Challapalli; Vadhiraja, B. M.; Ravichandran, Ramamoorthy; Joan, Mary; Pai, K. Dinesh

    2016-01-01

    Transmission of radiation fluence through patient's body has a correlation to the planned target dose. A method to estimate the delivered dose to target volumes was standardized using a beam level 0.6 cc ionization chamber (IC) positioned at electronic portal imaging device (EPID) plane from the measured transit signal (St) in patients with cancer of uterine cervix treated with three-dimensional conformal radiotherapy (3DCRT). The IC with buildup cap was mounted on linear accelerator EPID frame with fixed source to chamber distance of 146.3 cm, using a locally fabricated mount. Sts were obtained for different water phantom thicknesses and radiation field sizes which were then used to generate a calibration table against calculated midplane doses at isocenter (Diso,TPS), derived from the treatment planning system. A code was developed using MATLAB software which was used to estimate the in vivo dose at isocenter (Diso,Transit) from the measured Sts. A locally fabricated pelvic phantom validated the estimations of Diso,Transit before implementing this method on actual patients. On-line dose estimations were made (3 times during treatment for each patient) in 24 patients. The Diso,Transit agreement with Diso,TPS in phantom was within 1.7% and the mean percentage deviation with standard deviation is −1.37% ±2.03% (n = 72) observed in patients. Estimated in vivo dose at isocenter with this method provides a good agreement with planned ones which can be implemented as part of quality assurance in pelvic sites treated with simple techniques, for example, 3DCRT where there is a need for documentation of planned dose delivery. PMID:28144114

  4. On-line estimations of delivered radiation doses in three-dimensional conformal radiotherapy treatments of carcinoma uterine cervix patients in linear accelerator.

    PubMed

    Putha, Suman Kumar; Saxena, P U; Banerjee, S; Srinivas, Challapalli; Vadhiraja, B M; Ravichandran, Ramamoorthy; Joan, Mary; Pai, K Dinesh

    2016-01-01

    Transmission of radiation fluence through patient's body has a correlation to the planned target dose. A method to estimate the delivered dose to target volumes was standardized using a beam level 0.6 cc ionization chamber (IC) positioned at electronic portal imaging device (EPID) plane from the measured transit signal (S t ) in patients with cancer of uterine cervix treated with three-dimensional conformal radiotherapy (3DCRT). The IC with buildup cap was mounted on linear accelerator EPID frame with fixed source to chamber distance of 146.3 cm, using a locally fabricated mount. S t s were obtained for different water phantom thicknesses and radiation field sizes which were then used to generate a calibration table against calculated midplane doses at isocenter (D iso,TPS ), derived from the treatment planning system. A code was developed using MATLAB software which was used to estimate the in vivo dose at isocenter (D iso,Transit ) from the measured S t s. A locally fabricated pelvic phantom validated the estimations of D iso,Transit before implementing this method on actual patients. On-line dose estimations were made (3 times during treatment for each patient) in 24 patients. The D iso,Transit agreement with D iso,TPS in phantom was within 1.7% and the mean percentage deviation with standard deviation is -1.37% ±2.03% ( n = 72) observed in patients. Estimated in vivo dose at isocenter with this method provides a good agreement with planned ones which can be implemented as part of quality assurance in pelvic sites treated with simple techniques, for example, 3DCRT where there is a need for documentation of planned dose delivery.

  5. [Overall treatment time assessment of radiotherapy delivered in a curative intent: A prospective study].

    PubMed

    Petit, C; Suissa, A; Finet, A; Comte, A; Soltys, B; Daveau, C; Ali, D; Dessard-Diana, B; Giraud, P; Housset, M; Durdux, C

    2015-12-01

    To assess the overall treatment time of radiotherapy delivered with curative intent in a cohort of 185 consecutive patients and the causes of this possible delay. If delay, to propose corrective actions. We report a single-center prospective study including all consecutive patients receiving a radiation therapy with curative intent, from 1st December 2013 to 28th February 2014, on the three linear accelerators of the radiotherapy department. For each fraction missed, the causes of non-completion were prospectively collected. This analysis took into account the following parameters: age, sex, occupation, transport type and duration, tumour localization, radiation dose, concomitant chemotherapy, hospitalization, type of linear accelerator. One hundred and fifty-five patients were included in the study (183 evaluable, two did not complete treatment). The overall treatment time was respected for 31 patients (17%). It was lengthened on 4.6 days (d) (0-29 d; median: 3d). The mean number of delayed fractions was 3.4 (0-17; median: 2). The reasons of delay were: breakdown 32.2%; maintenance 29.3%; holiday 11%; treatment toxicity 9.4%; inadequate planning 8.6%; other disease 3.9%; treatment refusal 2.1%; unspecified personal reasons 1.5%; refusal to wait 0.8%; transportation 0.3%; error of communication 0.3%; other 0.6%. Two parameters had a significant impact on the overall treatment time: the type of linear accelerator in relation to breakdown occurrence (P<0.001) and transportation duration (more or less than 40 min, P=0.022). One hundred and thirty-eight patients (75%) and 79 patients (43%) were treated on one or more than two Saturdays. Treatment on Saturday significantly reduced the overall treatment time (median, 1.9 d; P<0.001). The overall treatment time was globally respected excluding break down and maintenance. Their impact on the overall treatment time is minimized by the systematic opening of the department on Saturdays. Copyright © 2015 Société fran

  6. Very Early Salvage Radiotherapy Improves Distant Metastasis-Free Survival.

    PubMed

    Abugharib, Ahmed; Jackson, William C; Tumati, Vasu; Dess, Robert T; Lee, Jae Y; Zhao, Shuang G; Soliman, Moaaz; Zumsteg, Zachary S; Mehra, Rohit; Feng, Felix Y; Morgan, Todd M; Desai, Neil; Spratt, Daniel E

    2017-03-01

    Early salvage radiotherapy following radical prostatectomy for prostate cancer is commonly advocated in place of adjuvant radiotherapy. We aimed to determine the optimal definition of early salvage radiotherapy. We performed a multi-institutional retrospective study of 657 men who underwent salvage radiotherapy between 1986 and 2013. Two comparisons were made to determine the optimal definition of early salvage radiotherapy, including 1) the time from radical prostatectomy to salvage radiotherapy (less than 9, 9 to 21, 22 to 47 or greater than 48 months) and 2) the level of detectable pre-salvage radiotherapy prostate specific antigen (0.01 to 0.2, greater than 0.2 to 0.5 or greater than 0.5 ng/ml). Outcomes included freedom from salvage androgen deprivation therapy, and biochemical relapse-free, distant metastases-free and prostate cancer specific survival. Median followup was 9.8 years. Time from radical prostatectomy to salvage radiotherapy did not correlate with 10-year biochemical relapse-free survival rates (R 2 = 0.18). Increasing pre-salvage radiotherapy prostate specific antigen strongly correlated with biochemical relapse-free survival (R 2 = 0.91). Increasing detectable pre-salvage radiotherapy prostate specific antigen (0.01 to 0.2, greater than 0.2 to 0.5 and greater than 0.5 ng/ml) predicted worse 10-year biochemical relapse-free survival (62%, 44% and 27%), freedom from salvage androgen deprivation therapy (77%, 66% and 49%), distant metastases-free survival (86%, 79% and 66%, each p <0.001) and prostate cancer specific survival (93%, 89% and 80%, respectively, p = 0.001). On multivariable analysis early salvage radiotherapy (prostate specific antigen greater than 0.2 to 0.5 ng/ml) was associated with a twofold increase in biochemical failure, use of salvage androgen deprivation therapy and distant metastases compared to very early salvage radiotherapy (prostate specific antigen 0.01 to 0.2 ng/ml). The duration from radical prostatectomy to salvage

  7. Risk-adaptive radiotherapy

    NASA Astrophysics Data System (ADS)

    Kim, Yusung

    Currently, there is great interest in integrating biological information into intensity-modulated radiotherapy (IMRT) treatment planning with the aim of boosting high-risk tumor subvolumes. Selective boosting of tumor subvolumes can be accomplished without violating normal tissue complication constraints using information from functional imaging. In this work we have developed a risk-adaptive optimization-framework that utilizes a nonlinear biological objective function. Employing risk-adaptive radiotherapy for prostate cancer, it is possible to increase the equivalent uniform dose (EUD) by up to 35.4 Gy in tumor subvolumes having the highest risk classification without increasing normal tissue complications. Subsequently, we have studied the impact of functional imaging accuracy, and found on the one hand that loss in sensitivity had a large impact on expected local tumor control, which was maximal when a low-risk classification for the remaining low risk PTV was chosen. While on the other hand loss in specificity appeared to have a minimal impact on normal tissue sparing. Therefore, it appears that in order to improve the therapeutic ratio a functional imaging technique with a high sensitivity, rather than specificity, is needed. Last but not least a comparison study between selective boosting IMRT strategies and uniform-boosting IMRT strategies yielding the same EUD to the overall PTV was carried out, and found that selective boosting IMRT considerably improves expected TCP compared to uniform-boosting IMRT, especially when lack of control of the high-risk tumor subvolumes is the cause of expected therapy failure. Furthermore, while selective boosting IMRT, using physical dose-volume objectives, did yield similar rectal and bladder sparing when compared its equivalent uniform-boosting IMRT plan, risk-adaptive radiotherapy, utilizing biological objective functions, did yield a 5.3% reduction in NTCP for the rectum. Hence, in risk-adaptive radiotherapy the

  8. Radiotherapy for glioma during pregnancy: fetal dose estimates, risk assessment and clinical management.

    PubMed

    Haba, Y; Twyman, N; Thomas, S J; Overton, C; Dendy, P; Burnet, N G

    2004-05-01

    Cancer in pregnancy is relatively uncommon, but constitutes a major problem. We report the measurement of scatter dose to the fetus and the estimated fetal risk from that exposure in an illustrative case of a patient, 20 weeks pregnant, with a grade 3 anaplastic astrocytoma. A clinical decision was made to withhold radiotherapy, if possible, until after delivery. Sequential magnetic resonance imaging (MRI) showed no progression during the pregnancy. In the event, she was managed conservatively until the successful completion of her pregnancy. In case radiotherapy was required, an estimation of the fetal risk was made. Phantom measurements were undertaken to assess the likely fetal dose. Film badges were used to estimate the scattered radiation energy. Measurements were made on a Varian 600C at 6 MV and Asea Brown Boveri (ABB) accelerator at 8 and 16 MV. Doses were measured at 30, 45 and 60 cm from the isocentre; the fetus was assumed to lie at about 60 cm and not closer than 45 cm from the isocentre. Estimated doses to the position of the fetus were lowest with the 6 MV Varian accelerator. Using this machine without additional abdominal shielding, the estimated dose on the surface at 45 cm from the tumour volume was 2.2 cGy for a tumour dose of 54 Gy; using the ABB accelerator, the dose varied between 49-59 cGy. The energy of scattered radiation was in the range 208-688 keV, so that additional shielding would be practical to further reduce the fetal dose. The risk of cancer up to the age of 15 years attributable to radiation is 1 in 1700 per cGy, of which half will be fatal (i.e. 1 in 3300 per cGy). A dose of 2.2 cGy adds a risk of fatal cancer by the age 15 years of only 1 in 1500. Because the addition of shielding might halve the fetal dose, this risk should be reduced to 1 in 3000. For comparison, the overall UK risk of cancer up to the age 15 years is 1 in 650. In conclusion, careful choice of linear accelerator for the treatment of a pregnant woman and the use

  9. Clinical advantages of carbon-ion radiotherapy

    NASA Astrophysics Data System (ADS)

    Tsujii, Hirohiko; Kamada, Tadashi; Baba, Masayuki; Tsuji, Hiroshi; Kato, Hirotoshi; Kato, Shingo; Yamada, Shigeru; Yasuda, Shigeo; Yanagi, Takeshi; Kato, Hiroyuki; Hara, Ryusuke; Yamamoto, Naotaka; Mizoe, Junetsu

    2008-07-01

    Carbon-ion radiotherapy (C-ion RT) possesses physical and biological advantages. It was started at NIRS in 1994 using the Heavy Ion Medical Accelerator in Chiba (HIMAC); since then more than 50 protocol studies have been conducted on almost 4000 patients with a variety of tumors. Clinical experiences have demonstrated that C-ion RT is effective in such regions as the head and neck, skull base, lung, liver, prostate, bone and soft tissues, and pelvic recurrence of rectal cancer, as well as for histological types including adenocarcinoma, adenoid cystic carcinoma, malignant melanoma and various types of sarcomas, against which photon therapy could be less effective. Furthermore, when compared with photon and proton RT, a significant reduction of overall treatment time and fractions has been accomplished without enhancing toxicities. Currently, the number of irradiation sessions per patient averages 13 fractions spread over approximately three weeks. This means that in a carbon therapy facility a larger number of patients than is possible with other modalities can be treated over the same period of time.

  10. Five-year Local Control in a Phase II Study of Hypofractionated Intensity Modulated Radiation Therapy With an Incorporated Boost for Early Stage Breast Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Freedman, Gary M., E-mail: Gary.Freedman@uphs.upenn.edu; Anderson, Penny R.; Bleicher, Richard J.

    Purpose: Conventional radiation fractionation of 1.8-2 Gy per day for early stage breast cancer requires daily treatment for 6-7 weeks. We report the 5-year results of a phase II study of intensity modulated radiation therapy (IMRT), hypofractionation, and incorporated boost that shortened treatment time to 4 weeks. Methods and Materials: The study design was phase II with a planned accrual of 75 patients. Eligibility included patients aged {>=}18 years, Tis-T2, stage 0-II, and breast conservation. Photon IMRT and an incorporated boost was used, and the whole breast received 2.25 Gy per fraction for a total of 45 Gy, and themore » tumor bed received 2.8 Gy per fraction for a total of 56 Gy in 20 treatments over 4 weeks. Patients were followed every 6 months for 5 years. Results: Seventy-five patients were treated from December 2003 to November 2005. The median follow-up was 69 months. Median age was 52 years (range, 31-81). Median tumor size was 1.4 cm (range, 0.1-3.5). Eighty percent of tumors were node negative; 93% of patients had negative margins, and 7% of patients had close (>0 and <2 mm) margins; 76% of cancers were invasive ductal type: 15% were ductal carcinoma in situ, 5% were lobular, and 4% were other histology types. Twenty-nine percent of patients 29% had grade 3 carcinoma, and 20% of patients had extensive in situ carcinoma; 11% of patients received chemotherapy, 36% received endocrine therapy, 33% received both, and 20% received neither. There were 3 instances of local recurrence for a 5-year actuarial rate of 2.7%. Conclusions: This 4-week course of hypofractionated radiation with incorporated boost was associated with excellent local control, comparable to historical results of 6-7 weeks of conventional whole-breast fractionation with sequential boost.« less

  11. Survey on deep learning for radiotherapy.

    PubMed

    Meyer, Philippe; Noblet, Vincent; Mazzara, Christophe; Lallement, Alex

    2018-07-01

    More than 50% of cancer patients are treated with radiotherapy, either exclusively or in combination with other methods. The planning and delivery of radiotherapy treatment is a complex process, but can now be greatly facilitated by artificial intelligence technology. Deep learning is the fastest-growing field in artificial intelligence and has been successfully used in recent years in many domains, including medicine. In this article, we first explain the concept of deep learning, addressing it in the broader context of machine learning. The most common network architectures are presented, with a more specific focus on convolutional neural networks. We then present a review of the published works on deep learning methods that can be applied to radiotherapy, which are classified into seven categories related to the patient workflow, and can provide some insights of potential future applications. We have attempted to make this paper accessible to both radiotherapy and deep learning communities, and hope that it will inspire new collaborations between these two communities to develop dedicated radiotherapy applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Five-year results of a prospective clinical trial investigating accelerated partial breast irradiation using 3D conformal radiotherapy after lumpectomy for early stage breast cancer.

    PubMed

    Horst, Kathleen C; Fasola, Carolina; Ikeda, Debra; Daniel, Bruce; Ognibene, Grant; Goffinet, Don R; Dirbas, Frederick M

    2016-08-01

    Accelerated partial breast irradiation (APBI) is emerging as an alternative to whole-breast irradiation. This study presents the results of a prospective trial evaluating 3-dimensional conformal radiotherapy (3D-CRT) to deliver APBI for early-stage breast cancer. Patients with unifocal stage 0-II breast cancer measuring ≤2.5 cm without lymph node involvement were eligible. After lumpectomy, 3D-CRT APBI was delivered to the lumpectomy cavity + margin (34-38.5 Gy in 10 fractions over 5 days). 141 patients with 143 breast cancers (2 bilateral) were treated with 3D-CRT APBI. Median age was 60. Median tumor size was 1.1 cm. At a median follow up of 60 months (range, 5-113), the 5-year and 8-year cumulative incidence rate of a true recurrence is 0.9%. The 5-year and 8-year cumulative incidence rates of an elsewhere failure are 2.4% and 4.4%, respectively. The 5-year and 8-year overall survival is 100% and 94%, respectively. Among the 62 patients with follow up >5 years, 95% had excellent/good cosmetic results. Our experience with 3D-CRT APBI demonstrates excellent cosmesis and local control. Longer follow up will be necessary to evaluate long-term efficacy and toxicity of 3D-CRT APBI. CLINICALTRIALS. NCT00185744. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Effectiveness of Radiotherapy for Elderly Patients With Glioblastoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, Jacob; Tsai, Ya-Yu; Chinnaiyan, Prakash

    Purpose: Radiotherapy plays a central role in the definitive treatment of glioblastoma. However, the optimal management of elderly patients with glioblastoma remains controversial, as the relative benefit in this patient population is unclear. To better understand the role that radiation plays in the treatment of glioblastoma in the elderly, we analyzed factors influencing patient survival using a large population-based registry. Methods and Materials: A total of 2,836 patients more than 70 years of age diagnosed with glioblastoma between 1993 and 2005 were identified from the Surveillance, Epidemiology, and End Results (SEER) registry. Demographic and clinical variables used in the analysismore » included gender, ethnicity, tumor size, age at diagnosis, surgery, and radiotherapy. Cancer-specific survival and overall survival were evaluated using the Kaplan-Meier method. Univariate and multivariate analysis were performed using Cox regression. Results: Radiotherapy was administered in 64% of these patients, and surgery was performed in 68%. Among 2,836 patients, 46% received surgery and radiotherapy, 22% underwent surgery only, 18% underwent radiotherapy only, and 14% did not undergo either treatment. The median survival for patients who underwent surgery and radiotherapy was 8 months. The median survival for patients who underwent radiotherapy only was 4 months, and for patients who underwent surgery only was 3 months. Those who received neither surgery nor radiotherapy had a median survival of 2 months (p < 0.001). Multivariate analysis showed that radiotherapy significantly improved cancer-specific survival (hazard ratio [HR], 0.43, 95% confidence interval [CI] 0.38-0.49) after adjusting for surgery, tumor size, gender, ethnicity, and age at diagnosis. Other factors associated with Cancer-specific survival included surgery, tumor size, age at diagnosis, and ethnicity. Analysis using overall survival as the endpoint yielded very similar results. Conclusions

  14. Scattered dose to gonads and associated risks from radiotherapy for common pediatric malignancies : a phantom study.

    PubMed

    Mazonakis, Michalis; Zacharopoulou, Fotini; Kachris, Stefanos; Varveris, Charalambos; Damilakis, John; Gourtsoyiannis, Nicholas

    2007-06-01

    To measure the scattered dose to ovaries and testes from radiotherapy for common pediatric malignancies and to assess the relevant risks for radiation-induced gonadal damage and hereditary disorders in future generations. Radiotherapy for central nervous system tumors, acute leukemia, neuroblastoma, Hodgkin's disease, Wilms' tumor, and sarcoma was simulated on three humanoid phantoms representing patients of 5, 10, and 15 years of age. Ovarian and testicular dose measurements were performed using thermoluminescent dosimeters on a linear accelerator with multileaf collimator (MLC) producing 6-MV X-rays. The effect of lead block introduction into the primary beam on the gonadal dose was evaluated. Gonadal dose from radiotherapy for abdominal tumors was measured using an 18-MV photon beam. For a tumor dose range of 12-55 Gy, the scattered dose to ovaries was 0.5-62.4 cGy depending upon the patient's age (corresponding phantom) and treatment site. The corresponding dose to testes was 0.4-145.0 cGy. The use of blocks for field shaping can increase the gonadal dose up to a factor of 2.0 compared to that measured using MLC. Abdominal irradiation with 18-MV instead of 6-MV X-rays reduced the gonadal dose by more than 1.3 times. For female and male patients, the risk for induction of hereditary disorders was less than 81 x 10(-4) and 188 x 10(-4), respectively. The present dosimetric data suggest that pediatric radiotherapy is not associated with a risk for permanent damage to gonads excluded from the treatment volume. The risk for development of hereditary disorders in offspring conceived after exposure is low.

  15. Preliminary experience in treatment of papillary and macular retinoblastoma: evaluation of local control and local complications after treatment with linear accelerator-based stereotactic radiotherapy with micromultileaf collimator as second-line or salvage treatment after chemotherapy.

    PubMed

    Pica, Alessia; Moeckli, Raphael; Balmer, Aubin; Beck-Popovic, Maja; Chollet-Rivier, Madeleine; Do, Huu-Phuoc; Weber, Damien C; Munier, Francis L

    2011-12-01

    To determine the local control and complication rates for children with papillary and/or macular retinoblastoma progressing after chemotherapy and undergoing stereotactic radiotherapy (SRT) with a micromultileaf collimator. Between 2004 and 2008, 11 children (15 eyes) with macular and/or papillary retinoblastoma were treated with SRT. The mean age was 19 months (range, 2-111). Of the 15 eyes, 7, 6, and 2 were classified as International Classification of Intraocular Retinoblastoma Group B, C, and E, respectively. The delivered dose of SRT was 50.4 Gy in 28 fractions using a dedicated micromultileaf collimator linear accelerator. The median follow-up was 20 months (range, 13-39). Local control was achieved in 13 eyes (87%). The actuarial 1- and 2-year local control rates were both 82%. SRT was well tolerated. Late adverse events were reported in 4 patients. Of the 4 patients, 2 had developed focal microangiopathy 20 months after SRT; 1 had developed a transient recurrence of retinal detachment; and 1 had developed bilateral cataracts. No optic neuropathy was observed. Linear accelerator-based SRT for papillary and/or macular retinoblastoma in children resulted in excellent tumor control rates with acceptable toxicity. Additional research regarding SRT and its intrinsic organ-at-risk sparing capability is justified in the framework of prospective trials. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Preliminary Experience in Treatment of Papillary and Macular Retinoblastoma: Evaluation of Local Control and Local Complications After Treatment With Linear Accelerator-Based Stereotactic Radiotherapy With Micromultileaf Collimator as Second-Line or Salvage Treatment After Chemotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pica, Alessia, E-mail: Alessia.Pica@chuv.ch; Moeckli, Raphael; Balmer, Aubin

    2011-12-01

    Purpose: To determine the local control and complication rates for children with papillary and/or macular retinoblastoma progressing after chemotherapy and undergoing stereotactic radiotherapy (SRT) with a micromultileaf collimator. Methods and Materials: Between 2004 and 2008, 11 children (15 eyes) with macular and/or papillary retinoblastoma were treated with SRT. The mean age was 19 months (range, 2-111). Of the 15 eyes, 7, 6, and 2 were classified as International Classification of Intraocular Retinoblastoma Group B, C, and E, respectively. The delivered dose of SRT was 50.4 Gy in 28 fractions using a dedicated micromultileaf collimator linear accelerator. Results: The median follow-upmore » was 20 months (range, 13-39). Local control was achieved in 13 eyes (87%). The actuarial 1- and 2-year local control rates were both 82%. SRT was well tolerated. Late adverse events were reported in 4 patients. Of the 4 patients, 2 had developed focal microangiopathy 20 months after SRT; 1 had developed a transient recurrence of retinal detachment; and 1 had developed bilateral cataracts. No optic neuropathy was observed. Conclusions: Linear accelerator-based SRT for papillary and/or macular retinoblastoma in children resulted in excellent tumor control rates with acceptable toxicity. Additional research regarding SRT and its intrinsic organ-at-risk sparing capability is justified in the framework of prospective trials.« less

  17. The influence of air humidity on an unsealed ionization chamber in a linear accelerator.

    PubMed

    Blad, B; Nilsson, P; Knöös, T

    1996-11-01

    The safe and accurate delivery of the prescribed absorbed dose is the central function of the dose monitoring and beam stabilization system in a medical linear accelerator. The absorbed dose delivered to the patient during radiotherapy is often monitored by a transmission ionization chamber. Therefore it is of utmost importance that the chamber behaves correctly. We have noticed that the sensitivity of an unsealed chamber in a Philips SL linear accelerator changes significantly, especially during and after the summer season. The reason for this is probably a corrosion effect of the conductive plates in the chamber due to the increased relative humidity during hot periods. We have found that the responses of the different ion chamber plates change with variations in air humidity and that they do not return to their original values when the air humidity is returned to ambient conditions.

  18. Radiotherapy in patients with connective tissue diseases.

    PubMed

    Giaj-Levra, Niccolò; Sciascia, Savino; Fiorentino, Alba; Fersino, Sergio; Mazzola, Rosario; Ricchetti, Francesco; Roccatello, Dario; Alongi, Filippo

    2016-03-01

    The decision to offer radiotherapy in patients with connective tissue diseases continues to be challenging. Radiotherapy might trigger the onset of connective tissue diseases by increasing the expression of self-antigens, diminishing regulatory T-cell activity, and activating effectors of innate immunity (dendritic cells) through Toll-like receptor-dependent mechanisms, all of which could potentially lead to breaks of immune tolerance. This potential risk has raised some debate among radiation oncologists about whether patients with connective tissue diseases can tolerate radiation as well as people without connective tissue diseases. Because the number of patients with cancer and connective tissue diseases needing radiotherapy will probably increase due to improvements in medical treatment and longer life expectancy, the issue of interactions between radiotherapy and connective tissue diseases needs to be clearer. In this Review, we discuss available data and evidence for patients with connective tissue diseases treated with radiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Time, space and technology in radiotherapy departments: how do these factors impact on patients' experiences of radiotherapy?

    PubMed

    Merchant, S; O'Connor, M; Halkett, G

    2017-03-01

    Radiation therapists (RTs) plan and deliver radiotherapy treatment for patients diagnosed with cancer. They need to communicate regularly with their patients and may have a role to play in reducing patient anxiety and distress. The objectives were to explore how the environment of radiotherapy departments supports or inhibits communication generally and information giving and supportive care provision in particular. An ethnographic approach was used to gather rich descriptive data through observations and interviews conducted in two Australian radiotherapy centres. Time, space and a technology driven culture was found to negatively affect the quality of interaction that occurred between RTs and their patients. This research has shown design/modification of spaces is needed in the radiotherapy environment to reflect a patient care centred culture and to enhance opportunities for RTs to provide supportive care for their patients. © 2015 John Wiley & Sons Ltd.

  20. Fast online Monte Carlo-based IMRT planning for the MRI linear accelerator

    NASA Astrophysics Data System (ADS)

    Bol, G. H.; Hissoiny, S.; Lagendijk, J. J. W.; Raaymakers, B. W.

    2012-03-01

    The MRI accelerator, a combination of a 6 MV linear accelerator with a 1.5 T MRI, facilitates continuous patient anatomy updates regarding translations, rotations and deformations of targets and organs at risk. Accounting for these demands high speed, online intensity-modulated radiotherapy (IMRT) re-optimization. In this paper, a fast IMRT optimization system is described which combines a GPU-based Monte Carlo dose calculation engine for online beamlet generation and a fast inverse dose optimization algorithm. Tightly conformal IMRT plans are generated for four phantom cases and two clinical cases (cervix and kidney) in the presence of the magnetic fields of 0 and 1.5 T. We show that for the presented cases the beamlet generation and optimization routines are fast enough for online IMRT planning. Furthermore, there is no influence of the magnetic field on plan quality and complexity, and equal optimization constraints at 0 and 1.5 T lead to almost identical dose distributions.

  1. Combined treatment of inoperable carcinomas of the uterine cervix with radiotherapy and regional hyperthermia. Results of a phase II trial.

    PubMed

    Dinges, S; Harder, C; Wurm, R; Buchali, A; Blohmer, J; Gellermann, J; Wust, P; Randow, H; Budach, V

    1998-10-01

    The disappointing results for inoperable, advanced tumors of the uterine cervix after conventional radiotherapy alone necessitates improving of radiation therapy. Simultaneous chemotherapy or altered radiation fractionation, such as accelerated regimen, increase acute toxicity and treatment is often difficult to deliver in the planned manner. The purpose of this phase II study was to investigate the toxicity and effectiveness of a combined approach with radiotherapy and regional hyperthermia. From January 1994 to October 1995 18 patients with advanced carcinomas of the uterine cervix were treated in combination with radiotherapy and hyperthermia. The patients were treated with 6 to 20 MV photons delivered by a linear accelerator in a 4-field-box technique to a total dose of 50.4 Gy in 28 fractions. In the first and fourth week 2 regional hyperthermia treatments were each applied with the Sigma-60 applicator from a BSD-2000 unit. After this a boost to the primary tumor was given with high-dose-rate iridium-192 brachytherapy by an afterloading technique with 4 x 5 Gy at point A to a total of 20 Gy and for the involved parametrium anterioposterior-posterioanterior to 9 Gy in 5 fractions. The acute toxicity was low and similar to an external radiotherapy alone treatment. No Grade III/IV acute toxicity was found. The median age was 47 years (range 34 to 67 years). In 16 of 18 patients a rapid tumor regression was observed during combined thermo-radiotherapy, which allowed the use of intracavitary high-dose-rate brachytherapy in these cases. Complete and partial remission were observed in 13 and 4 cases, respectively. One patient did not respond to the treatment. The median follow-up was 24 months (range 17 to 36 months). The local tumor control rate was 48% at 2 years. Median T20, T50 and T90 values were 41.7 degrees C (range 40.3 to 43.2 degrees C), 41.1 degrees C (range 39.2 to 42.5 degrees C) and 39.9 degrees C (range 37.7 to 41.9 degrees C), respectively. Cumulative

  2. Combined chemotherapy and radiotherapy (without surgery) compared with radiotherapy alone in localized carcinoma of the esophagus.

    PubMed

    Wong, R; Malthaner, R

    2001-01-01

    Esophageal carcinoma can be managed primarily with either a surgical or radiotherapeutic (non surgical) approach. Strategies to improve the outcome of either modality alone include the use of combined modalities. Combination chemotherapy radiotherapy is one approach that has been explored over the years with increasing application in clinical practice especially in North America. To evaluate the effectiveness of combined chemotherapy and radiotherapy versus radiotherapy alone in the outcome of patients with localized esophageal carcinoma. Outcomes of interest include overall survival, cause specific survival, local recurrence, dysphagia relief, quality of life, acute and chronic toxicities. The Cochrane strategy for identifying randomized trials was combined with MeSH headings including esophageal neoplasms, radiotherapy, chemotherapy combined modality, drug therapy combination. Medline, Cancerlit and Embase were searched using this strategy. In addition, the Cochrane library was also searched. References from relevant articles and personal files were included. Randomized controlled trials in patients with localized esophageal cancer, with one arm employing radiotherapy alone, and one arm employing combination radiotherapy chemotherapy were included. Studies comparing non chemotherapy agents such as pure radiotherapy sensitisers, immunostimulants, planned esophagectomy, were excluded. Data were extracted by two independent reviewers, and the trial quality was assessed using both the Jadad scoring and Detsky checklist. Sensitivity analysis was planned to explore sources of heterogeneity where heterogeneity existed. The factors hypothesized a priori included combination versus sequential treatment, quality of study, biological effective radiotherapy dose (i.e. Radiotherapy dose) cisplatin versus non cisplatin containing trials, and 5FU versus non 5FU containing trials. Odds Ratio (OR) and 95% confidence limits were used to assess the significance of the difference

  3. Combined chemotherapy and radiotherapy (without surgery) compared with radiotherapy alone in localized carcinoma of the esophagus.

    PubMed

    Rebecca, W O; Richard, M A

    2003-01-01

    Esophageal carcinoma can be managed primarily with either a surgical or radiotherapeutic (non surgical) approach. Strategies to improve the outcome of either modality alone include the use of combined modalities. Combination chemotherapy radiotherapy is one approach that has been explored over the years with increasing application in clinical practice especially in North America. To evaluate the effectiveness of combined chemotherapy and radiotherapy versus radiotherapy alone in the outcome of patients with localized esophageal carcinoma. Outcomes of interest include overall survival, cause specific survival, local recurrence, dysphagia relief, quality of life, acute and chronic toxicities. The Cochrane strategy for identifying randomized trials was combined with MeSH headings including esophageal neoplasms, radiotherapy, chemotherapy combined modality, drug therapy combination. MEDLINE, CancerLIT and EMBASE were searched using this strategy. In addition, the Cochrane library was also searched. References from relevant articles and personal files were included. Randomized controlled trials in patients with localized esophageal cancer, with one arm employing radiotherapy alone, and one arm employing combination radiotherapy chemotherapy were included. Studies comparing non chemotherapy agents such as pure radiotherapy sensitisers, immunostimulants, planned esophagectomy, were excluded. Data were extracted by two independent reviewers, and the trial quality was assessed using both the Jadad scoring and Detsky checklist. Sensitivity analysis was planned to explore sources of heterogeneity where heterogeneity existed. The factors hypothesized a priori included combination versus sequential treatment, quality of study, biological effective radiotherapy dose (i.e. Radiotherapy dose) cisplatin versus non cisplatin containing trials, and 5FU versus non 5FU containing trials. Odds Ratio (OR) and 95% confidence limits were used to assess the significance of the difference

  4. Tumor lymphocyte immune response to preoperative radiotherapy in locally advanced rectal cancer: The LYMPHOREC study.

    PubMed

    Mirjolet, C; Charon-Barra, C; Ladoire, S; Arbez-Gindre, F; Bertaut, A; Ghiringhelli, F; Leroux, A; Peiffert, D; Borg, C; Bosset, J F; Créhange, G

    2018-01-01

    Introduction : Some studies have suggested that baseline tumor-infiltrating-lymphocytes (TILs), such as CD8+ and FoxP3+ T-cells, may be associated with a better prognosis in colorectal cancer. We sought to investigate modulation of the immune response by preoperative radiotherapy (preopRT) and its impact on survival in locally advanced rectal cancer (LARC). Materials & Methods : We analyzed data for 237 patients with LARC who received RT. Density of TILS (CD8+ and FoxP3+) in intraepithelial (iTILs) and stromal compartments (sTILs) were evaluated from surgery pathological specimens and biopsies performed at baseline. The primary endpoint was to assess the impact of infiltration of the tumor or tumor site after preopRT on progression-free survival (PFS) and overall survival (OS). Secondary endpoints were the impact of dose fractionation scheme on TILs. Results : In univariate analysis, several factors significantly correlated (p<0.05) with PFS and/or OS (T-stage, M-stage, the delay between RT and surgery). A high level of post-treatment FoxP3+ TIL density correlated significantly with a better PFS (p = 0.007). In multivariate analysis, a decrease in the CD8+/FoxP3+ iTILs ratio after preopRT correlated with better PFS and OS (p = 0.049 and p = 0.024, respectively). More particularly, patients with a delta CD8+/FoxP3+ <-3.8 had better PFS and OS. Interestingly, the dose fractionation scheme significantly influenced the CD8 + /FoxP3 + ratio after treatment (p = 0.027) with a lower ratio with hypofractionated RT (≥2 Gy). Conclusion : Patients with LARC who had a significant decrease in the CD8+/FoxP3+ ratio after preopRT were more likely to live longer. This ratio needs to be validated prospectively to guide physicians in adjuvant treatment decision-making.

  5. Evidence-based optimal number of radiotherapy fractions for cancer: A useful tool to estimate radiotherapy demand.

    PubMed

    Wong, Karen; Delaney, Geoff P; Barton, Michael B

    2016-04-01

    The recently updated optimal radiotherapy utilisation model estimated that 48.3% of all cancer patients should receive external beam radiotherapy at least once during their disease course. Adapting this model, we constructed an evidence-based model to estimate the optimal number of fractions for notifiable cancers in Australia to determine equipment and workload implications. The optimal number of fractions was calculated based on the frequency of specific clinical conditions where radiotherapy is indicated and the evidence-based recommended number of fractions for each condition. Sensitivity analysis was performed to assess the impact of variables on the model. Of the 27 cancer sites, the optimal number of fractions for the first course of radiotherapy ranged from 0 to 23.3 per cancer patient, and 1.5 to 29.1 per treatment course. Brain, prostate and head and neck cancers had the highest average number of fractions per course. Overall, the optimal number of fractions was 9.4 per cancer patient (range 8.7-10.0) and 19.4 per course (range 18.0-20.7). These results provide valuable data for radiotherapy services planning and comparison with actual practice. The model can be easily adapted by inserting population-specific epidemiological data thus making it applicable to other jurisdictions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Hypofractionated Nodal Radiation Therapy for Breast Cancer Was Not Associated With Increased Patient-Reported Arm or Brachial Plexopathy Symptoms.

    PubMed

    Leong, Nelson; Truong, Pauline T; Tankel, Keith; Kwan, Winkle; Weir, Lorna; Olivotto, Ivo A

    2017-12-01

    To determine whether nodal radiation therapy (RT) for breast cancer using modest hypofractionation (HF) with 2.25 to 2.5 Gy per fraction (fx) was associated with increased patient-reported arm symptoms, compared with conventional fractionation (CF) ≤2 Gy/fx. Two cancer registries were used to identify subjects who received computed tomography-planned nodal RT for pT1-3, pN0-2, M0 breast cancer, from 2007 to 2010 at 2 cancer institutions. After ethics approval, patients were mailed an explanatory letter and the Self-reported Arm Symptom Scale, a validated instrument with 8 questions about arm symptoms and 5 related to activities of daily living. Clinicopathologic characteristics and Self-reported Arm Symptom Scale scores were compared between HF/CF cohorts using nonparametric analysis, χ 2 analysis, and multivariate ordinal regression. Of 1759 patients, 800 (45.5%) returned a completed survey. A total of 708 eligible cases formed the study cohort. Of these, 406 (57%) received HFRT (40 Gy/16 fx, 45 Gy/20 fx), and 302 (43%) received CFRT (45-50 Gy/25 fx, 50.4 Gy/28 fx). Median time interval after RT was 5.7 years. Forty-three percent and 75% of patients received breast-conserving surgery and chemotherapy, respectively. Twenty-two percent received breast boost RT, independent of fractionation. Median age at diagnosis was 59 years (HF) and 53 years (CF) (P<.001). The mean numbers of excised (n=12) and involved (n=3) nodes were similar between fractionation cohorts (P=.44), as were the mean sums of responses in arm symptoms (P=.17) and activities of daily living (P=.85). Patients receiving HF reported lower rates of shoulder stiffness (P=.04), trouble moving the arm (P=.02), and difficulty reaching overhead (P<.01) compared with the CF cohort. There was no difference in self-reported arm swelling or symptoms related to brachial plexopathy. Nodal RT with hypofractionation was not associated with increased patient-reported arm symptoms or functional deficits

  7. Gold Nanoparticle Hyperthermia Reduces Radiotherapy Dose

    PubMed Central

    Lin, Lynn; Slatkin, Daniel N.; Dilmanian, F. Avraham; Vadas, Timothy M.; Smilowitz, Henry M.

    2014-01-01

    Gold nanoparticles can absorb near infrared light, resulting in heating and ablation of tumors. Gold nanoparticles have also been used for enhancing the dose of X-rays in tumors during radiotherapy. The combination of hyperthermia and radiotherapy is synergistic, importantly allowing a reduction in X-ray dose with improved therapeutic results. Here we intratumorally infused small 15 nm gold nanoparticles engineered to be transformed from infrared-transparent to infrared-absorptive by the tumor, which were then heated by infrared followed by X-ray treatment. Synergy was studied using a very radioresistant subcutaneous squamous cell carcinoma (SCCVII) in mice. It was found that the dose required to control 50% of the tumors, normally 55 Gy, could be reduced to <15 Gy (a factor of >3.7). Gold nanoparticles therefore provide a method to combine hyperthermia and radiotherapy to drastically reduce the X-ray radiation needed, thus sparing normal tissue, reducing the side effects, and making radiotherapy more effective. PMID:24990355

  8. SU-F-T-479: Estimation of the Accuracy in Respiratory-Gated Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurosawa, T; Miyakawa, S; Sato, M

    Purpose: Irregular respiratory patterns affects dose outputs in respiratorygated radiotherapy and there is no commercially available quality assurance (QA) system for it. We designed and developed a patient specific QA system for respiratory-gated radiotherapy to estimate irradiated output. Methods: Our in-house QA system for gating was composed of a personal computer with the USB-FSIO electronic circuit connecting to the linear accelerator (ONCOR-K, Toshiba Medical Systems). The linac implements a respiratory gating system (AZ-733V, Anzai Medical). During the beam was on, 4.2 V square-wave pulses were continually sent to the system. Our system can receive and count the pulses. At first,more » our system and an oscilloscope were compared to check the performance of our system. Next, basic estimation models were generated when ionization-chamber measurements were performed in gating using regular sinusoidal wave patterns (2.0, 2.5, 4.0, 8.0, 15 sec/cycle). During gated irradiation with the regular patterns, the number of the pulses per one gating window was measured using our system. Correlation between the number of the pulses per one gating and dose per the gating window were assessed to generate the estimation model. Finally, two irregular respiratory patterns were created and the accuracy of the estimation was evaluated. Results: Compared to the oscilloscope, our system worked similarly. The basic models were generated with the accuracy within 0.1%. The results of the gated irradiations with two irregular respiratory patterns show good agreement within 0.4% estimation accuracy. Conclusion: Our developed system shows good estimation for even irregular respiration patterns. The system would be a useful tool to verify the output for respiratory-gated radiotherapy.« less

  9. Towards ion beam therapy based on laser plasma accelerators.

    PubMed

    Karsch, Leonhard; Beyreuther, Elke; Enghardt, Wolfgang; Gotz, Malte; Masood, Umar; Schramm, Ulrich; Zeil, Karl; Pawelke, Jörg

    2017-11-01

    Only few ten radiotherapy facilities worldwide provide ion beams, in spite of their physical advantage of better achievable tumor conformity of the dose compared to conventional photon beams. Since, mainly the large size and high costs hinder their wider spread, great efforts are ongoing to develop more compact ion therapy facilities. One promising approach for smaller facilities is the acceleration of ions on micrometre scale by high intensity lasers. Laser accelerators deliver pulsed beams with a low pulse repetition rate, but a high number of ions per pulse, broad energy spectra and high divergences. A clinical use of a laser based ion beam facility requires not only a laser accelerator providing beams of therapeutic quality, but also new approaches for beam transport, dosimetric control and tumor conformal dose delivery procedure together with the knowledge of the radiobiological effectiveness of laser-driven beams. Over the last decade research was mainly focused on protons and progress was achieved in all important challenges. Although currently the maximum proton energy is not yet high enough for patient irradiation, suggestions and solutions have been reported for compact beam transport and dose delivery procedures, respectively, as well as for precise dosimetric control. Radiobiological in vitro and in vivo studies show no indications of an altered biological effectiveness of laser-driven beams. Laser based facilities will hardly improve the availability of ion beams for patient treatment in the next decade. Nevertheless, there are possibilities for a need of laser based therapy facilities in future.

  10. Monte Carlo simulations in radiotherapy dosimetry.

    PubMed

    Andreo, Pedro

    2018-06-27

    The use of the Monte Carlo (MC) method in radiotherapy dosimetry has increased almost exponentially in the last decades. Its widespread use in the field has converted this computer simulation technique in a common tool for reference and treatment planning dosimetry calculations. This work reviews the different MC calculations made on dosimetric quantities, like stopping-power ratios and perturbation correction factors required for reference ionization chamber dosimetry, as well as the fully realistic MC simulations currently available on clinical accelerators, detectors and patient treatment planning. Issues are raised that include the necessity for consistency in the data throughout the entire dosimetry chain in reference dosimetry, and how Bragg-Gray theory breaks down for small photon fields. Both aspects are less critical for MC treatment planning applications, but there are important constraints like tissue characterization and its patient-to-patient variability, which together with the conversion between dose-to-water and dose-to-tissue, are analysed in detail. Although these constraints are common to all methods and algorithms used in different types of treatment planning systems, they make uncertainties involved in MC treatment planning to still remain "uncertain".

  11. Peripheral dose measurements with diode and thermoluminescence dosimeters for intensity modulated radiotherapy delivered with conventional and un-conventional linear accelerator

    PubMed Central

    Kinhikar, Rajesh; Gamre, Poonam; Tambe, Chandrashekhar; Kadam, Sudarshan; Biju, George; Suryaprakash; Magai, C. S.; Dhote, Dipak; Shrivastava, Shyam; Deshpande, Deepak

    2013-01-01

    The objective of this paper was to measure the peripheral dose (PD) with diode and thermoluminescence dosimeter (TLD) for intensity modulated radiotherapy (IMRT) with linear accelerator (conventional LINAC), and tomotherapy (novel LINAC). Ten patients each were selected from Trilogy dual-energy and from Hi-Art II tomotherapy. Two diodes were kept at 20 and 25 cm from treatment field edge. TLDs (LiF:MgTi) were also kept at same distance. TLDs were also kept at 5, 10, and 15 cm from field edge. The TLDs were read with REXON reader. The readings at the respective distance were recorded for both diode and TLD. The PD was estimated by taking the ratio of measured dose at the particular distance to the prescription dose. PD was then compared with diode and TLD for LINAC and tomotherapy. Mean PD for LINAC with TLD and diode was 2.52 cGy (SD 0.69), 2.07 cGy (SD 0.88) at 20 cm, respectively, while at 25 cm, it was 1.94 cGy (SD 0.58) and 1.5 cGy (SD 0.75), respectively. Mean PD for tomotherapy with TLD and diode was 1.681 cGy SD 0.53) and 1.58 (SD 0.44) at 20 cm, respectively. The PD was 1.24 cGy (SD 0.42) and 1.088 cGy (SD 0.35) at 25 cm, respectively, for tomotherapy. Overall, PD from tomotherapy was found lower than LINAC by the factor of 1.2-1.5. PD measurement is essential to find out the potential of secondary cancer. PD for both (conventional LINAC) and novel LINACs (tomotherapy) were measured and compared with each other. The comparison of the values for PD presented in this work and those published in the literature is difficult because of the different experimental conditions. The diode and TLD readings were reproducible and both the detector readings were comparable. PMID:23531765

  12. Updates on clinical studies of selenium supplementation in radiotherapy

    PubMed Central

    2014-01-01

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation in patients with cancer who underwent radiotherapy. The studies were conducted worldwide including European, American and Asian countries between 1987 and 2012. Plasma, serum or whole blood selenium levels were common parameters used to assess the effects of radiotherapy and the selenium supplementation status. Selenium supplementation improved the general conditions of the patients, improved their quality of life and reduced the side effects of radiotherapy. At the dose of selenium used in these studies (200–500 μg/day), selenium supplementation did not reduce the effectiveness of radiotherapy, and no toxicities were reported. Selenium supplementation may offer specific benefits for several types of cancer patients who undergo radiotherapy. Because high-dose selenium and long-term supplementation may be unsafe due to selenium toxicity, more evidence-based information and additional research are needed to ensure the therapeutic benefits of selenium supplementation. PMID:24885670

  13. Conventional and conformal technique of external beam radiotherapy in locally advanced cervical cancer: Dose distribution, tumor response, and side effects

    NASA Astrophysics Data System (ADS)

    Mutrikah, N.; Winarno, H.; Amalia, T.; Djakaria, M.

    2017-08-01

    The objective of this study was to compare conventional and conformal techniques of external beam radiotherapy (EBRT) in terms of the dose distribution, tumor response, and side effects in the treatment of locally advanced cervical cancer patients. A retrospective cohort study was conducted on cervical cancer patients who underwent EBRT before brachytherapy in the Radiotherapy Department of Cipto Mangunkusumo Hospital. The prescribed dose distribution, tumor response, and acute side effects of EBRT using conventional and conformal techniques were investigated. In total, 51 patients who underwent EBRT using conventional techniques (25 cases using Cobalt-60 and 26 cases using a linear accelerator (LINAC)) and 29 patients who underwent EBRT using conformal techniques were included in the study. The distribution of the prescribed dose in the target had an impact on the patient’s final response to EBRT. The complete response rate of patients to conformal techniques was significantly greater (58%) than that of patients to conventional techniques (42%). No severe acute local side effects were seen in any of the patients (Radiation Therapy Oncology Group (RTOG) grades 3-4). The distribution of the dose and volume to the gastrointestinal tract affected the proportion of mild acute side effects (RTOG grades 1-2). The urinary bladder was significantly greater using conventional techniques (Cobalt-60/LINAC) than using conformal techniques at 72% and 78% compared to 28% and 22%, respectively. The use of conformal techniques in pelvic radiation therapy is suggested in radiotherapy centers with CT simulators and 3D Radiotherapy Treatment Planning Systems (RTPSs) to decrease some uncertainties in radiotherapy planning. The use of AP/PA pelvic radiation techniques with Cobalt-60 should be limited in body thicknesses equal to or less than 18 cm. When using conformal techniques, delineation should be applied in the small bowel, as it is considered a critical organ according to RTOG

  14. Enhancing radiotherapy for lung cancer using immunoadjuvants delivered in situ from new design radiotherapy biomaterials: a preclinical study

    NASA Astrophysics Data System (ADS)

    Hao, Yao; Yasmin-Karim, Sayeda; Moreau, Michele; Sinha, Neeharika; Sajo, Erno; Ngwa, Wilfred

    2016-12-01

    Studies show that radiotherapy of a primary tumor in combination with immunoadjuvants (IA) can result in increased survival or immune-mediated regression of metastasis outside the radiation field, a phenomenon known as abscopal effect. However, toxicities due to repeated systematic administration of IA have been shown to be a major obstacle in clinical trials. To minimize the toxicities and prime a more potent immune response, Ngwa et al have proposed that inert radiotherapy biomaterials such as fiducials could be upgraded to multifunctional ones loaded with IA for in situ delivery directly into the tumor sub-volume at no additional inconvenience to patients. In this preliminary study, the potential of such an approach is investigated for lung cancer using anti-CD40 antibody. First the benefit of using the anti-CD40 delivered in situ to enhance radiotherapy was tested in mice with subcutaneous tumors generated with the Lewis Lung cancer cell line LL/2 (LLC-1). The tumors were implanted on both flanks of the mice to simulate metastasis. Tumors on one flank were treated with and without anti-CD40 and the survival benefits compared. An experimentally determined in vivo diffusion coefficient for nanoparticles was then employed to estimate the time for achieving intratumoral distribution of the needed minimal concentrations of anti-CD40 nanoparticles if released from a multifuntional radiotherapy biomaterials. The studies show that the use of anti-CD40 significantly enhanced radiotherapy effect, slowing the growth of the treated and untreated tumors, and increasing survival. Meanwhile our calculations indicate that for a 2-4 cm tumor and 7 mg g-1 IA concentrations, it would take 4.4-17.4 d, respectively, following burst release, for the required concentration of IA nanoparticles to accumulate throughout the tumor during image-guided radiotherapy. The distribution of IA could be customized as a function of loading concentrations or nanoparticle size to fit current

  15. Enhancing radiotherapy for lung cancer using immunoadjuvants delivered in situ from new design radiotherapy biomaterials: a preclinical study.

    PubMed

    Hao, Yao; Yasmin-Karim, Sayeda; Moreau, Michele; Sinha, Neeharika; Sajo, Erno; Ngwa, Wilfred

    2016-12-21

    Studies show that radiotherapy of a primary tumor in combination with immunoadjuvants (IA) can result in increased survival or immune-mediated regression of metastasis outside the radiation field, a phenomenon known as abscopal effect. However, toxicities due to repeated systematic administration of IA have been shown to be a major obstacle in clinical trials. To minimize the toxicities and prime a more potent immune response, Ngwa et al have proposed that inert radiotherapy biomaterials such as fiducials could be upgraded to multifunctional ones loaded with IA for in situ delivery directly into the tumor sub-volume at no additional inconvenience to patients. In this preliminary study, the potential of such an approach is investigated for lung cancer using anti-CD40 antibody. First the benefit of using the anti-CD40 delivered in situ to enhance radiotherapy was tested in mice with subcutaneous tumors generated with the Lewis Lung cancer cell line LL/2 (LLC-1). The tumors were implanted on both flanks of the mice to simulate metastasis. Tumors on one flank were treated with and without anti-CD40 and the survival benefits compared. An experimentally determined in vivo diffusion coefficient for nanoparticles was then employed to estimate the time for achieving intratumoral distribution of the needed minimal concentrations of anti-CD40 nanoparticles if released from a multifuntional radiotherapy biomaterials. The studies show that the use of anti-CD40 significantly enhanced radiotherapy effect, slowing the growth of the treated and untreated tumors, and increasing survival. Meanwhile our calculations indicate that for a 2-4 cm tumor and 7 mg g -1 IA concentrations, it would take 4.4-17.4 d, respectively, following burst release, for the required concentration of IA nanoparticles to accumulate throughout the tumor during image-guided radiotherapy. The distribution of IA could be customized as a function of loading concentrations or nanoparticle size to fit current

  16. MO-F-16A-02: Simulation of a Medical Linear Accelerator for Teaching Purposes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carlone, M; Lamey, M; Anderson, R

    Purpose: Detailed functioning of linear accelerator physics is well known. Less well developed is the basic understanding of how the adjustment of the linear accelerator's electrical components affects the resulting radiation beam. Other than the text by Karzmark, there is very little literature devoted to the practical understanding of linear accelerator functionality targeted at the radiotherapy clinic level. The purpose of this work is to describe a simulation environment for medical linear accelerators with the purpose of teaching linear accelerator physics. Methods: Varian type lineacs were simulated. Klystron saturation and peak output were modelled analytically. The energy gain of anmore » electron beam was modelled using load line expressions. The bending magnet was assumed to be a perfect solenoid whose pass through energy varied linearly with solenoid current. The dose rate calculated at depth in water was assumed to be a simple function of the target's beam current. The flattening filter was modelled as an attenuator with conical shape, and the time-averaged dose rate at a depth in water was determined by calculating kerma. Results: Fifteen analytical models were combined into a single model called SIMAC. Performance was verified systematically by adjusting typical linac control parameters. Increasing klystron pulse voltage increased dose rate to a peak, which then decreased as the beam energy was further increased due to the fixed pass through energy of the bending magnet. Increasing accelerator beam current leads to a higher dose per pulse. However, the energy of the electron beam decreases due to beam loading and so the dose rate eventually maximizes and the decreases as beam current was further increased. Conclusion: SIMAC can realistically simulate the functionality of a linear accelerator. It is expected to have value as a teaching tool for both medical physicists and linear accelerator service personnel.« less

  17. Moderate Hypofractionated Protracted Radiation Therapy and Dose Escalation for Prostate Cancer: Do Dose and Overall Treatment Time Matter?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kountouri, Melpomeni; Zilli, Thomas; Rouzaud, Michel

    2016-02-01

    Purpose: This was a retrospective study of 2 sequential dose escalation regimens of twice-weekly 4 Gy/fractions hypofractionated intensity modulated radiation therapy (IMRT): 56 Gy and 60 Gy delivered within a protracted overall treatment time (OTT) of 6.5 and 7 weeks, respectively. Methods and Materials: 163 prostate cancer patients with cT1c-T3a disease and nodal involvement risk ≤20% (Roach index) were treated twice weekly to the prostate ± seminal vesicles with 2 sequential dose-escalated IMRT schedules: 56 Gy (14 × 4 Gy, n=81) from 2003 to 2007 and 60 Gy (15 × 4 Gy, n=82) from 2006 to 2010. Patient repositioning was made with bone matching on portal images. Gastrointestinal (GI) and genitourinary (GU) toxicities weremore » scored according to the Common Terminology Criteria for Adverse Events version 3.0 grading scale. Results: There were no significant differences regarding the acute GU and GI toxicities in the 2 dose groups. The median follow-up times were 80.2 months (range, 4.5-121 months) and 56.5 months (range, 1.4-91.2 months) for patients treated to 56 and 60 Gy, respectively. The 5-year grade ≥2 late GU toxicity-free survivals with 56 Gy and 60 Gy were 96 ± 2.3% and 78.2 ± 5.1% (P=.001), respectively. The 5-year grade ≥2 late GI toxicity-free survivals with 56 Gy and 60 Gy were 98.6 ± 1.3% and 85.1 ± 4.5% (P=.005), respectively. Patients treated with 56 Gy showed a 5-year biochemical progression-free survival (bPFS) of 80.8 ± 4.7%, worse than patients treated with 60 Gy (93.2 ± 3.9%, P=.007). A trend for a better 5-year distant metastasis-free survival was observed among patients treated in the high-dose group (95.3 ± 2.7% vs 100%, P=.073, respectively). On multivariate analysis, only the 60-Gy group predicted for a better bPFS (P=.016, hazard ratio = 4.58). Conclusions: A single 4-Gy additional fraction in patients treated with a hypofractionated protracted IMRT schedule of 14 × 4

  18. Cytoreductive prostate radiotherapy in oligometastatic prostate cancer: a single centre analysis of toxicity and clinical outcome.

    PubMed

    Riva, Giulia; Marvaso, Giulia; Augugliaro, Matteo; Zerini, Dario; Fodor, Cristiana; Musi, Gennaro; De Cobelli, Ottavio; Orecchia, Roberto; Jereczek-Fossa, Barbara Alicja

    2017-01-01

    The current standard of care for patients with metastatic prostate cancer (mPCa) at diagnosis is androgen deprivation therapy (ADT) with or without anti-androgen and chemotherapy. The aim of this study was to define the role of a local radiotherapy (RT) treatment in the mPCa setting. We retrospectively reviewed data of patients with PCa and bone oligometastases at diagnosis treated in our institution with ADT followed by cytoreductive prostate-RT with or without RT on metastases. Biochemical and clinical failure (BF, CF), overall survival (OS) and RT-toxicity were assessed. We identified 22 patients treated with ADT and external-beam RT on primary between June 2008 and March 2016. All of them but four were also treated for bone metastases. RT on primary with moderately and extremely hypofractionated regimes started after 10.3 months (3.9-51.7) from ADT. After a median follow-up of 26.4 months (10.3-55.5), 20 patients are alive. Twelve patients showed BF after a median time of 23 months (14.5-104) and CF after a median of 23.6 months (15.3-106.1) from the start of ADT. Three patients became castration resistant, starting a new therapy; median time to castration resistance was 31.03 months (range: 29.9-31.5 months). According to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC), only one patient developed acute grade 3 genitourinary toxicity. No late grade >2 adverse events were observed. Prostate RT in oligometastatic patients is safe and offers long-lasting local control. When compared to ADT alone, RT on primary seems to improve biochemical control and long-term survival; however, this hypothesis should be investigated in prospective studies. Further research is warranted.

  19. Radiotherapy demand and activity in England 2006-2020.

    PubMed

    Round, C E; Williams, M V; Mee, T; Kirkby, N F; Cooper, T; Hoskin, P; Jena, R

    2013-09-01

    This paper compares the predictions of radiotherapy demand for England from the Malthus model with those from the earlier National Radiotherapy Advisory Group (NRAG) model, from the international literature and also with observed radiotherapy usage in England as a whole as recorded in the English radiotherapy dataset (RTDS). We reviewed the evidence base for radiotherapy for each type and stage of cancer using national and international guidelines, meta-analyses, systematic reviews and key clinical trials. Twenty-two decision trees were constructed and radiotherapy demand was calculated using English cancer incidence data for 2007, 2008 and 2009, accurate to the Primary Care Trust (PCT) level (population 91,500-1,282,384). The stage at presentation was obtained from English cancer registry data. In predictive mode, the model can take account of changes in cancer incidence as the population grows and ages. The Malthus model indicates reduced indications for radiotherapy, principally for lung cancer and rarer tumours. Our estimate of the proportion of patients who should receive radiotherapy at some stage of their illness is 40.6%. This is lower than previous estimates of about 50%. Nevertheless, the overall estimate of demand in terms of attendances is similar for the NRAG and Malthus models. The latter models that 48,827 attendances should have been delivered per million population in 2011. National data from RTDS show 32,071 attendances per million in 2011. A 50% increase in activity would be required to match estimated demand. This underprovision extends across all cancers and represents reduced access and the use of dose fractionation at odds with international norms of evidence-based practice. By 2016, demand is predicted to grow to about 55,206 attendances per million and by 2020 to 60,057. Services have increased their activity by 14% between 2006 and 2011, but estimated demand has increased by 11%. Access remains low and English radiotherapy dose

  20. Radiotherapy for Vestibular Schwannomas: A Critical Review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murphy, Erin S., E-mail: murphye3@ccf.or; Suh, John H.

    2011-03-15

    Vestibular schwannomas are slow-growing tumors of the myelin-forming cells that cover cranial nerve VIII. The treatment options for patients with vestibular schwannoma include active observation, surgical management, and radiotherapy. However, the optimal treatment choice remains controversial. We have reviewed the available data and summarized the radiotherapeutic options, including single-session stereotactic radiosurgery, fractionated conventional radiotherapy, fractionated stereotactic radiotherapy, and proton beam therapy. The comparisons of the various radiotherapy modalities have been based on single-institution experiences, which have shown excellent tumor control rates of 91-100%. Both stereotactic radiosurgery and fractionated stereotactic radiotherapy have successfully improved cranial nerve V and VII preservation tomore » >95%. The mixed data regarding the ideal hearing preservation therapy, inherent biases in patient selection, and differences in outcome analysis have made the comparison across radiotherapeutic modalities difficult. Early experience using proton therapy for vestibular schwannoma treatment demonstrated local control rates of 84-100% but disappointing hearing preservation rates of 33-42%. Efforts to improve radiotherapy delivery will focus on refined dosimetry with the goal of reducing the dose to the critical structures. As future randomized trials are unlikely, we suggest regimented pre- and post-treatment assessments, including validated evaluations of cranial nerves V, VII, and VIII, and quality of life assessments with long-term prospective follow-up. The results from such trials will enhance the understanding of therapy outcomes and improve our ability to inform patients.« less

  1. Locally Advanced Stage IV Squamous Cell Carcinoma of the Head and Neck: Impact of Pre-Radiotherapy Hemoglobin Level and Interruptions During Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rades, Dirk; Department of Radiation Oncology, University Medical Center Hamburg-Eppendorf, Hamburg; Stoehr, Monika

    2008-03-15

    Purpose: Stage IV head and neck cancer patients carry a poor prognosis. Clear understanding of prognostic factors can help to optimize care for the individual patient. This study investigated 11 potential prognostic factors including pre-radiotherapy hemoglobin level and interruptions during radiotherapy for overall survival (OS), metastases-free survival (MFS), and locoregional control (LC) after radiochemotherapy. Methods and Materials: Eleven factors were investigated in 153 patients receiving radiochemotherapy for Stage IV squamous cell head and neck cancer: age, gender, Karnofsky performance score (KPS), tumor site, grading, T stage, N stage, pre-radiotherapy hemoglobin level, surgery, chemotherapy type, and interruptions during radiotherapy >1 week.more » Results: On multivariate analysis, improved OS was associated with KPS 90-100 (relative risk [RR], 2.36; 95% confidence interval [CI], 1.20-4.93; p = .012), hemoglobin {>=}12 g/dL (RR, 1.88; 95% CI, 1.01-3.53; p = .048), and no radiotherapy interruptions (RR, 2.59; 95% CI, 1.15-5.78; p = .021). Improved LC was significantly associated with lower T stage (RR, 2.17; 95% CI, 1.16-4.63; p = .013), hemoglobin {>=}12 g/dL (RR, 4.12; 95% CI, 1.92-9.09; p < .001), surgery (RR, 2.67; 95% CI, 1.28-5.88; p = .008), and no radiotherapy interruptions (RR, 3.32; 95% CI, 1.26-8.79; p = .015). Improved MFS was associated with KPS 90-100 (RR, 3.41; 95% CI, 1.46-8.85; p = .012). Conclusions: Significant predictors for outcome in Stage IV head and neck cancer were performance status, stage, surgery, pre-radiotherapy hemoglobin level, and interruptions during radiotherapy >1 week. It appears important to avoid anemia and radiotherapy interruptions to achieve the best treatment results.« less

  2. Radiotherapy Treatment Planning for Testicular Seminoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilder, Richard B., E-mail: richardbwilder@yahoo.com; Buyyounouski, Mark K.; Efstathiou, Jason A.

    2012-07-15

    Virtually all patients with Stage I testicular seminoma are cured regardless of postorchiectomy management. For patients treated with adjuvant radiotherapy, late toxicity is a major concern. However, toxicity may be limited by radiotherapy techniques that minimize radiation exposure of healthy normal tissues. This article is an evidence-based review that provides radiotherapy treatment planning recommendations for testicular seminoma. The minority of Stage I patients who choose adjuvant treatment over surveillance may be considered for (1) para-aortic irradiation to 20 Gy in 10 fractions, or (2) carboplatin chemotherapy consisting of area under the curve, AUC = 7 Multiplication-Sign 1-2 cycles. Two-dimensional radiotherapymore » based on bony anatomy is a simple and effective treatment for Stage IIA or IIB testicular seminoma. Centers with expertise in vascular and nodal anatomy may consider use of anteroposterior-posteroanterior fields based on three-dimensional conformal radiotherapy instead. For modified dog-leg fields delivering 20 Gy in 10 fractions, clinical studies support placement of the inferior border at the top of the acetabulum. Clinical and nodal mapping studies support placement of the superior border of all radiotherapy fields at the top of the T12 vertebral body. For Stage IIA and IIB patients, an anteroposterior-posteroanterior boost is then delivered to the adenopathy with a 2-cm margin to the block edge. The boost dose consists of 10 Gy in 5 fractions for Stage IIA and 16 Gy in 8 fractions for Stage IIB. Alternatively, bleomycin, etoposide, and cisplatin chemotherapy for 3 cycles or etoposide and cisplatin chemotherapy for 4 cycles may be delivered to Stage IIA or IIB patients (e.g., if they have a horseshoe kidney, inflammatory bowel disease, or a history of radiotherapy).« less

  3. Acceleration modules in linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Heng; Deng, Jian-Jun

    2014-05-01

    The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.

  4. WE-EF-BRD-01: Past, Present and Future: MRI-Guided Radiotherapy From 2005 to 2025

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lagendijk, J.

    MRI-guided treatment is a growing area of medicine, particularly in radiotherapy and surgery. The exquisite soft tissue anatomic contrast offered by MRI, along with functional imaging, makes the use of MRI during therapeutic procedures very attractive. Challenging the utility of MRI in the therapy room are many issues including the physics of MRI and the impact on the environment and therapeutic instruments, the impact of the room and instruments on the MRI; safety, space, design and cost. In this session, the applications and challenges of MRI-guided treatment will be described. The session format is: Past, present and future: MRI-guided radiotherapymore » from 2005 to 2025: Jan Lagendijk Battling Maxwell’s equations: Physics challenges and solutions for hybrid MRI systems: Paul Keall I want it now!: Advances in MRI acquisition, reconstruction and the use of priors to enable fast anatomic and physiologic imaging to inform guidance and adaptation decisions: Yanle Hu MR in the OR: The growth and applications of MRI for interventional radiology and surgery: Rebecca Fahrig Learning Objectives: To understand the history and trajectory of MRI-guided radiotherapy To understand the challenges of integrating MR imaging systems with linear accelerators To understand the latest in fast MRI methods to enable the visualisation of anatomy and physiology on radiotherapy treatment timescales To understand the growing role and challenges of MRI for image-guided surgical procedures My disclosures are publicly available and updated at: http://sydney.edu.au/medicine/radiation-physics/about-us/disclosures.php.« less

  5. Internet-based computer technology on radiotherapy.

    PubMed

    Chow, James C L

    2017-01-01

    Recent rapid development of Internet-based computer technologies has made possible many novel applications in radiation dose delivery. However, translational speed of applying these new technologies in radiotherapy could hardly catch up due to the complex commissioning process and quality assurance protocol. Implementing novel Internet-based technology in radiotherapy requires corresponding design of algorithm and infrastructure of the application, set up of related clinical policies, purchase and development of software and hardware, computer programming and debugging, and national to international collaboration. Although such implementation processes are time consuming, some recent computer advancements in the radiation dose delivery are still noticeable. In this review, we will present the background and concept of some recent Internet-based computer technologies such as cloud computing, big data processing and machine learning, followed by their potential applications in radiotherapy, such as treatment planning and dose delivery. We will also discuss the current progress of these applications and their impacts on radiotherapy. We will explore and evaluate the expected benefits and challenges in implementation as well.

  6. Radiotherapy with or without chemotherapy in muscle-invasive bladder cancer.

    PubMed

    James, Nicholas D; Hussain, Syed A; Hall, Emma; Jenkins, Peter; Tremlett, Jean; Rawlings, Christine; Crundwell, Malcolm; Sizer, Bruce; Sreenivasan, Thiagarajan; Hendron, Carey; Lewis, Rebecca; Waters, Rachel; Huddart, Robert A

    2012-04-19

    Radiotherapy is an alternative to cystectomy in patients with muscle-invasive bladder cancer. In other disease sites, synchronous chemoradiotherapy has been associated with increased local control and improved survival, as compared with radiotherapy alone. In this multicenter, phase 3 trial, we randomly assigned 360 patients with muscle-invasive bladder cancer to undergo radiotherapy with or without synchronous chemotherapy. The regimen consisted of fluorouracil (500 mg per square meter of body-surface area per day) during fractions 1 to 5 and 16 to 20 of radiotherapy and mitomycin C (12 mg per square meter) on day 1. Patients were also randomly assigned to undergo either whole-bladder radiotherapy or modified-volume radiotherapy (in which the volume of bladder receiving full-dose radiotherapy was reduced) in a partial 2-by-2 factorial design (results not reported here). The primary end point was survival free of locoregional disease. Secondary end points included overall survival and toxic effects. At 2 years, rates of locoregional disease-free survival were 67% (95% confidence interval [CI], 59 to 74) in the chemoradiotherapy group and 54% (95% CI, 46 to 62) in the radiotherapy group. With a median follow-up of 69.9 months, the hazard ratio in the chemoradiotherapy group was 0.68 (95% CI, 0.48 to 0.96; P=0.03). Five-year rates of overall survival were 48% (95% CI, 40 to 55) in the chemoradiotherapy group and 35% (95% CI, 28 to 43) in the radiotherapy group (hazard ratio, 0.82; 95% CI, 0.63 to 1.09; P=0.16). Grade 3 or 4 adverse events were slightly more common in the chemoradiotherapy group than in the radiotherapy group during treatment (36.0% vs. 27.5%, P=0.07) but not during follow-up (8.3% vs. 15.7%, P=0.07). Synchronous chemotherapy with fluorouracil and mitomycin C combined with radiotherapy significantly improved locoregional control of bladder cancer, as compared with radiotherapy alone, with no significant increase in adverse events. (Funded by Cancer

  7. Quality assurance in radiotherapy.

    PubMed

    Kouloulias, V E

    2003-03-01

    In 1999, the European Organisation for Research and Treatment of Cancer (EORTC), being a European pioneer in the field of cancer research as well as in quality assurance (QA), launched an Emmanuel van der Schueren fellowship for QA in radiotherapy. In this paper, the work that has been done during the first E. van der Schueren fellowship is reported, focusing on four phase III EORTC clinical trials: 22921 for rectal cancer, 22961 and 22991 for prostate cancer and 22922 for breast cancer. A historical review of the QA programme of the EORTC Radiotherapy group during the past 20 years is included.

  8. Hypo-Fractionated Conformal Radiation Therapy to the Tumor Bed after Segmental Mastectomy

    DTIC Science & Technology

    2007-07-01

    reatment (17). Prone positioning of the patient rapidly •-merged as the best technique, because it minimizes move- neni of the target breast tissue...treatment ohase and 46 completed treatment. Three patients were lost to follow-up before initiating any treat- neni . and 1 patient discontinued treatment...Dossibility of completing the course of postsegmental nasiectomv radiotherapy (RT) in a smaller number of treat- nenis within a shorter Deriod is very

  9. Adjuvant radiotherapy for stage I endometrial cancer.

    PubMed

    Kong, A; Johnson, N; Cornes, P; Simera, I; Collingwood, M; Williams, C; Kitchener, H

    2007-04-18

    The role of adjuvant radiotherapy (both pelvic external beam radiotherapy and vaginal intracavity brachytherapy) in stage I endometrial cancer following total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH and BSO) remains unclear. To assess the efficacy of adjuvant radiotherapy following surgery for stage I endometrial cancer. The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CancerLit, Physician Data Query (PDQ) of National Cancer Institute. Handsearching was also carried out where appropriate. Randomised controlled trials (RCTs) which compared adjuvant radiotherapy versus no radiotherapy following surgery for patients with stage I endometrial cancer were included. Quality of the studies was assessed and data collected using a predefined data collection form. The primary endpoint was overall survival. Secondary endpoints were locoregional recurrence, distant recurrence and endometrial cancer death. Data on quality of life (QOL) and morbidity were also collected. A meta-analysis on included trials was performed using the Cochrane Collaboration Review Manager Software 4.2. The meta-analysis was performed on four trials (1770 patients). The addition of pelvic external beam radiotherapy to surgery reduced locoregional recurrence, a relative risk (RR) of 0.28 (95% confidence interval (CI) 0.17 to 0.44, p < 0.00001), which is a 72% reduction in the risk of pelvic relapse (95% CI 56% to 83%) and an absolute risk reduction of 6% (95% CI of 4 to 8%). The number needed to treat (NNT) to prevent one locoregional recurrence is 16.7 patients (95% CI 12.5 to 25). The reduction in the risk of locoregional recurrence did not translate into either a reduction in the risk of distant recurrence or death from all causes or endometrial cancer death. A subgroup analysis of women with multiple high risk factors (including stage 1c and grade 3) showed a trend toward the reduction in the risk of death from all causes and endometrial cancer

  10. Radiation-induced heart disease in lung cancer radiotherapy

    PubMed Central

    Ming, Xin; Feng, Yuanming; Yang, Chengwen; Wang, Wei; Wang, Ping; Deng, Jun

    2016-01-01

    Abstract Background: Radiation-induced heart disease (RIHD), which affects the patients’ prognosis with both acute and late side effects, has been published extensively in the radiotherapy of breast cancer, lymphoma and other benign diseases. Studies on RIHD in lung cancer radiotherapy, however, are less extensive and clear even though the patients with lung cancer are delivered with higher doses to the heart during radiation treatment. Methods: In this article, after extensive literature search and analysis, we reviewed the current evidence on RIHD in lung cancer patients after their radiation treatments and investigated the potential risk factors for RIHD as compared to other types of cancers. Result: Cardiac toxicity has been found highly relevant in lung cancer radiotherapy. So far, the crude incidence of cardiac complications in the lung cancer patients after radiotherapy has been up to 33%. Conclusion: The dose to the heart, the lobar location of tumor, the treatment modality, the history of heart and pulmonary disease and smoking were considered as potential risk factors for RIHD in lung cancer radiotherapy. As treatment techniques improve over the time with better prognosis for lung cancer survivors, an improved prediction model can be established to further reduce the cardiac toxicity in lung cancer radiotherapy. PMID:27741117

  11. Radiotherapy-induced hypopituitarism: a review.

    PubMed

    Sathyapalan, Thozhukat; Dixit, Sanjay

    2012-05-01

    Hypopituitarism is a disorder caused by impaired hormonal secretions from the hypothalamic-pituitary axis. Radiotherapy is the most common cause of iatrogenic hypopituitarism. The hypothalamic-pituitary axis inadvertently gets irradiated in patients receiving prophylactic cranial radiotherapy for leukemia, total body irradiation and radiotherapy for intracranial, base skull, sinonasal and nasopharyngeal tumors. Radiation-induced hypopituitarism (RIH) is insidious, progressive and largely nonreversible. Mostly, RIH involves one hypothalamic-pituitary axis; however, multiple hormonal axes deficiency starts developing at higher doses. Although the clinical effects of the hypopituitarism are more profound in children and young adults, its implications in older adults are being increasingly recognized. The risk continues to persist or increase up to 10 years following radiation exposure. The clinical management of hypopituitarism is challenging both for the patients and healthcare providers. Here we have reviewed the scale of the problem, the risk factors and the management of RIH.

  12. Intraoperative radiation therapy using mobile electron linear accelerators: report of AAPM Radiation Therapy Committee Task Group No. 72.

    PubMed

    Beddar, A Sam; Biggs, Peter J; Chang, Sha; Ezzell, Gary A; Faddegon, Bruce A; Hensley, Frank W; Mills, Michael D

    2006-05-01

    Intraoperative radiation therapy (IORT) has been customarily performed either in a shielded operating suite located in the operating room (OR) or in a shielded treatment room located within the Department of Radiation Oncology. In both cases, this cancer treatment modality uses stationary linear accelerators. With the development of new technology, mobile linear accelerators have recently become available for IORT. Mobility offers flexibility in treatment location and is leading to a renewed interest in IORT. These mobile accelerator units, which can be transported any day of use to almost any location within a hospital setting, are assembled in a nondedicated environment and used to deliver IORT. Numerous aspects of the design of these new units differ from that of conventional linear accelerators. The scope of this Task Group (TG-72) will focus on items that particularly apply to mobile IORT electron systems. More specifically, the charges to this Task Group are to (i) identify the key differences between stationary and mobile electron linear accelerators used for IORT, (ii) describe and recommend the implementation of an IORT program within the OR environment, (iii) present and discuss radiation protection issues and consequences of working within a nondedicated radiotherapy environment, (iv) describe and recommend the acceptance and machine commissioning of items that are specific to mobile electron linear accelerators, and (v) design and recommend an efficient quality assurance program for mobile systems.

  13. Beam related response of in vivo diode detectors for external radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baci, Syrja, E-mail: sbarci2013@gmail.com; Telhaj, Ervis; Malkaj, Partizan

    2016-03-25

    In Vivo Dosimetry (IVD) is a set of methods used in cancer treatment clinics to determine the real dose of radiation absorbed by target volume in a patient’s body. IVD has been widely implemented in radiotherapy treatment centers and is now recommended part of Quality Assurance program by many International health and radiation organizations. Because of cost and lack of specialized personnel, IVD has not been practiced as yet, in Albanian radiotherapy clinics. At Hygeia Hospital Tirana, patients are irradiated with high energy photons generated by Elekta Synergy Accelerators. We have recently started experimenting with the purpose of establishing anmore » IVD practice at this hospital. The first set of experiments was aimed at calibration of diodes that are going to be used for IVD. PMMA, phantoms by PTW were used to calibrate p – type Si, semiconductor diode dosimeters, made by PTW Freiburg for entrance dose. Response of the detectors is affected by energy of the beam, accumulated radiation dose, dose rate, temperature, angle against the beam axis, etc. Here we present the work done for calculating calibration factor and correction factors of source to surface distance, field size, and beam incidence for the entrance dose for both 6 MV photon beam and 18 MV photon beam. Dependence of dosimeter response was found to be more pronounced with source to surface distance as compared to other variables investigated.« less

  14. Management of elderly patients with glioblastoma-multiforme-a systematic review.

    PubMed

    Almadani, Asmaa; Sanjay, Dixit; Chris, Rowland-Hill; Shailendra, Achawal; Chitoor, Rajaraman; Gerry, O'Reilly; Robin, Highley; Masood, Hussain; Louise, Baker; Lynne, Gill; Holly, Morris; Mohan, Hingorani

    2018-03-09

    The management of elderly patients with glioblastoma-multiforme (GBM) remains poorly defined with many experts in the past advocating best supportive care, in view of limited evidence on efficacy of more aggressive treatment protocols. There is randomised evidence (NORDIC and NA-O8 studies) to support the use of surgery followed by adjuvant monotherapy with either radiotherapy (RT) using hypofractionated regimes (e.g. 36 Gy in 6 fractions OR 40 Gy in 15 fractions) or chemotherapy with temozolomide (TMZ) in patients expressing methylation of promoter for O 6 -methylguanine-DNA methyltransferase enzyme. However, the role of combined-modality therapy involving the use of combined RT and TMZ protocols has remained controversial with data from the EORTC (European Organisation for Research and Treatment of Cancer)-NCIC (National Cancer Institute of Canada) studies indicating that patients more than 65 years of age may not benefit significantly from combining standard RT fractionation using 60 Gy in 30 fractions with concurrent and adjuvant TMZ. More recently, randomised data has emerged on combining hypofractionated RT with concurrent and adjuvant TMZ. We provide a comprehensive review of literature with the aim of defining an evidence-based algorithm for management of elderly glioblastoma-multiforme population.

  15. Surgery Followed by Radiotherapy Versus Radiotherapy Alone for Metastatic Spinal Cord Compression From Unfavorable Tumors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rades, Dirk, E-mail: Rades.Dirk@gmx.net; Huttenlocher, Stefan; Bajrovic, Amira

    Purpose: Despite a previously published randomized trial, controversy exists regarding the benefit of adding surgery to radiotherapy for metastatic spinal cord compression (MSCC). It is thought that patients with MSCC from relatively radioresistant tumors or tumors associated with poor functional outcome after radiotherapy alone may benefit from surgery. This study focuses on these tumors. Methods and Materials: Data from 67 patients receiving surgery plus radiotherapy (S+RT) were matched to 134 patients (1:2) receiving radiotherapy alone (RT). Groups were matched for 10 factors and compared for motor function, ambulatory status, local control, and survival. Additional separate matched-pair analyses were performed formore » patients receiving direct decompressive surgery plus stabilization of involved vertebrae (DDSS) and patients receiving laminectomy (LE). Results: Improvement of motor function occurred in 22% of patients after S+RT and 16% after RT (p = 0.25). Posttreatment ambulatory rates were 67% and 61%, respectively (p = 0.68). Of nonambulatory patients, 29% and 19% (p = 0.53) regained ambulatory status. One-year local control rates were 85% and 89% (p = 0.87). One-year survival rates were 38% and 24% (p = 0.20). The matched-pair analysis of patients receiving LE showed no significant differences between both therapies. In the matched-pair analysis of patients receiving DDSS, improvement of motor function occurred more often after DDSS+RT than RT (28% vs. 19%, p = 0.024). Posttreatment ambulatory rates were 86% and 67% (p = 0.30); 45% and 18% of patients regained ambulatory status (p = 0.29). Conclusions: Patients with MSCC from an unfavorable primary tumor appeared to benefit from DDSS but not LE when added to radiotherapy in terms of improved functional outcome.« less

  16. Recruitment in Radiotherapy

    ERIC Educational Resources Information Center

    Deeley, T. J.; And Others

    1976-01-01

    The Faculty Board of Radiotherapy and Oncology of the Royal College of Radiobiologists surveyed the factors thought to influence recruitment into the specialty. Possible factors listed in replies of 36 questionnaires are offered. (LBH)

  17. A singular value decomposition linear programming (SVDLP) optimization technique for circular cone based robotic radiotherapy.

    PubMed

    Liang, Bin; Li, Yongbao; Wei, Ran; Guo, Bin; Xu, Xuang; Liu, Bo; Li, Jiafeng; Wu, Qiuwen; Zhou, Fugen

    2018-01-05

    With robot-controlled linac positioning, robotic radiotherapy systems such as CyberKnife significantly increase freedom of radiation beam placement, but also impose more challenges on treatment plan optimization. The resampling mechanism in the vendor-supplied treatment planning system (MultiPlan) cannot fully explore the increased beam direction search space. Besides, a sparse treatment plan (using fewer beams) is desired to improve treatment efficiency. This study proposes a singular value decomposition linear programming (SVDLP) optimization technique for circular collimator based robotic radiotherapy. The SVDLP approach initializes the input beams by simulating the process of covering the entire target volume with equivalent beam tapers. The requirements on dosimetry distribution are modeled as hard and soft constraints, and the sparsity of the treatment plan is achieved by compressive sensing. The proposed linear programming (LP) model optimizes beam weights by minimizing the deviation of soft constraints subject to hard constraints, with a constraint on the l 1 norm of the beam weight. A singular value decomposition (SVD) based acceleration technique was developed for the LP model. Based on the degeneracy of the influence matrix, the model is first compressed into lower dimension for optimization, and then back-projected to reconstruct the beam weight. After beam weight optimization, the number of beams is reduced by removing the beams with low weight, and optimizing the weights of the remaining beams using the same model. This beam reduction technique is further validated by a mixed integer programming (MIP) model. The SVDLP approach was tested on a lung case. The results demonstrate that the SVD acceleration technique speeds up the optimization by a factor of 4.8. Furthermore, the beam reduction achieves a similar plan quality to the globally optimal plan obtained by the MIP model, but is one to two orders of magnitude faster. Furthermore, the SVDLP

  18. A singular value decomposition linear programming (SVDLP) optimization technique for circular cone based robotic radiotherapy

    NASA Astrophysics Data System (ADS)

    Liang, Bin; Li, Yongbao; Wei, Ran; Guo, Bin; Xu, Xuang; Liu, Bo; Li, Jiafeng; Wu, Qiuwen; Zhou, Fugen

    2018-01-01

    With robot-controlled linac positioning, robotic radiotherapy systems such as CyberKnife significantly increase freedom of radiation beam placement, but also impose more challenges on treatment plan optimization. The resampling mechanism in the vendor-supplied treatment planning system (MultiPlan) cannot fully explore the increased beam direction search space. Besides, a sparse treatment plan (using fewer beams) is desired to improve treatment efficiency. This study proposes a singular value decomposition linear programming (SVDLP) optimization technique for circular collimator based robotic radiotherapy. The SVDLP approach initializes the input beams by simulating the process of covering the entire target volume with equivalent beam tapers. The requirements on dosimetry distribution are modeled as hard and soft constraints, and the sparsity of the treatment plan is achieved by compressive sensing. The proposed linear programming (LP) model optimizes beam weights by minimizing the deviation of soft constraints subject to hard constraints, with a constraint on the l 1 norm of the beam weight. A singular value decomposition (SVD) based acceleration technique was developed for the LP model. Based on the degeneracy of the influence matrix, the model is first compressed into lower dimension for optimization, and then back-projected to reconstruct the beam weight. After beam weight optimization, the number of beams is reduced by removing the beams with low weight, and optimizing the weights of the remaining beams using the same model. This beam reduction technique is further validated by a mixed integer programming (MIP) model. The SVDLP approach was tested on a lung case. The results demonstrate that the SVD acceleration technique speeds up the optimization by a factor of 4.8. Furthermore, the beam reduction achieves a similar plan quality to the globally optimal plan obtained by the MIP model, but is one to two orders of magnitude faster. Furthermore, the SVDLP

  19. [Use of filgrastim, granulocyte colony stimulating factor (G-CSF), in radiotherapy to reduce drop-outs because of radiogenic leukopenia].

    PubMed

    Gava, A; Bertossi, L; Ferrarese, F; Coghetto, F; Marazzato, G; Andrulli, A D; Zorat, P L

    1998-03-01

    Radiotherapy patients are at risk of developing leukopenia, which risk depends on the irradiated volume, the rate of irradiated bone marrow and the radiation dose. Radiogenic leukopenia may cause radiotherapy drop-out, with consequent effects, on local tumor control and clinical outcome. The introduction of granulocyte growth factors, such as filgrastim, has permitted to accelerate normal neutrophil count recovery in irradiation-related neutropenia both in vitro and animal models; clinical experience in humans is still lacking, relative to both indications and scheduling. In the Oncologic Radiotherapy Department of Treviso Hospital, 31 patients irradiated for Hodgkin disease, rectal cancer and other malignancies, who presented leukopenia requiring treatment discontinuation, were given filgrastim to assess its actual effect in avoiding further drop-outs and to compare two administration schedules (2 or 3 vials, 30 MIU, weekly). Filgrastim treatment was continued throughout the radiotherapy cycles, for 1 to 5 weeks. Eighteen patients had received previous chemotherapy and 11 were undergoing concurrent 5-fluorouracil chemotherapy-irradiation. A mean 203% increase in leukocyte count was observed (136% in the patients treated with 2 vials/week and 274% in those receiving 3 vials/week); this increase was more apparent in women that in men (256% versus 91%) and slightly higher in patients 50 years old and with target volumes < 5000 ml. Filgrastin treatment was well tolerated by all patients, with no discontinuations due to adverse effects; 9 patients (29%) reported skeletal pain, which was marked in 2 of them only. Eighty percent of patients completed all the radiotherapy cycles with no discontinuation, while 6 patients dropped out because leukopenia persisted. Biweekly filgrastim administration was effective to prevent unscheduled radiotherapy discontinuation in 75% of patients and triweekly administration was effective in 86% of patients. In our experience, filgrastim

  20. PET imaging in adaptive radiotherapy of gastrointestinal tumours.

    PubMed

    Bulens, Philippe; Thomas, Melissa; Deroose, Christophe M; Haustermans, Karin

    2018-06-04

    Radiotherapy is the standard of care in the multimodality treatment of a variety of gastrointestinal (GI) tumours, such as oesophageal cancer, gastric cancer, rectal cancer and anal cancer. Additionally, radiotherapy has served as an alternative for surgery in patients with liver cancer, cancer of the biliary tract and pancreatic cancer. Positron-emission tomography (PET), generally in combination with computed tomography (CT), has an established role in the diagnosis, response assessment and (re-)staging of several GI tumours. However, the additional value of PET in adaptive radiotherapy, i.e. during the radiation treatment course and in the delineation process, is still unclear. When performed during radiotherapy, PET aims at assessing treatment-induced variations in functional tumour volumes to reduce the radiation target volume. Moreover, in the radiation treatment planning, tumour delineation could be more accurate by incorporating PET to identify the metabolic tumour volume. This review focuses on the additional value of PET for adaptive radiotherapy protocols as well as for the target volume adaptation for individualised treatment strategies in oesophageal, gastric, pancreatic, liver, biliary tract, rectal and anal neoplasms.

  1. An accelerated technique for irradiation of malignant canine nasal and paranasal sinus tumors.

    PubMed

    Adams, W M; Miller, P E; Vail, D M; Forrest, L J; MacEwen, E G

    1998-01-01

    Tumor and normal tissue response was assessed in 21 dogs with malignant nasal tumors given 42 Gy cobalt radiation in 9 or 10 fractions over 11 to 13 days. Local tumor/clinical relapse recurred in 68% of dogs, with a median relapse free interval (RFI) of 270 days. Median survival was 428 days. One year survival for all dogs was 60%. RFI and survival times are better than, or similar to, previous reports of dogs treated with radiotherapy only. Acute radiation effects were severe in one dog. Late effects were severe in six of 15 dogs (40%) with durable tumor control. Late effects included bilateral blindness (3), osteoradionecrosis (3), and seizures (1). These six dogs had a median survival of 705 days. Loss of vision occurred in at least one eye in nine dogs (47%). Tumor staging based on CT findings was predictive for survival duration. Tumor histology was not predictive of outcome. Labrador Retrievers were significantly over-represented. Despite comparable or improved tumor control and survival times provided by this accelerated protocol, relative to other radiotherapy reports, local failure remains the major cause of death, and late radiation effects can be severe in dogs with durable tumor control.

  2. Contribution of FDOPA PET to radiotherapy planning for advanced glioma

    NASA Astrophysics Data System (ADS)

    Dowson, Nicholas; Fay, Michael; Thomas, Paul; Jeffree, Rosalind; McDowall, Robert; Winter, Craig; Coulthard, Alan; Smith, Jye; Gal, Yaniv; Bourgeat, Pierrick; Salvado, Olivier; Crozier, Stuart; Rose, Stephen

    2014-03-01

    Despite radical treatment with surgery, radiotherapy and chemotherapy, advanced gliomas recur within months. Geographic misses in radiotherapy planning may play a role in this seemingly ineluctable recurrence. Planning is typically performed on post-contrast MRIs, which are known to underreport tumour volume relative to FDOPA PET scans. FDOPA PET fused with contrast enhanced MRI has demonstrated greater sensitivity and specificity than MRI alone. One sign of potential misses would be differences between gross target volumes (GTVs) defined using MRI alone and when fused with PET. This work examined whether such a discrepancy may occur. Materials and Methods: For six patients, a 75 minute PET scan using 3,4-dihydroxy-6-18F-fluoro-L-phynel-alanine (18F-FDOPA) was taken within 2 days of gadolinium enhanced MRI scans. In addition to standard radiotherapy planning by an experienced radiotherapy oncologist, a second gross target volume (GTV) was defined by an experienced nuclear medicine specialist for fused PET and MRI, while blinded to the radiotherapy plans. The volumes from standard radiotherapy planning were compared to the PET defined GTV. Results: The comparison indicated radiotherapy planning would change in several cases if FDOPA PET data was available. PET-defined contours were external to 95% prescribed dose for several patients. However, due to the radiotherapy margins, the discrepancies were relatively small in size and all received a dose of 50 Gray or more. Conclusions: Given the limited size of the discrepancies it is uncertain that geographic misses played a major role in patient outcome. Even so, the existence of discrepancies indicates that FDOPA PET could assist in better defining margins when planning radiotherapy for advanced glioma, which could be important for highly conformal radiotherapy plans.

  3. Adjuvant radiotherapy after breast conserving surgery - a comparative effectiveness research study.

    PubMed

    Corradini, Stefanie; Niyazi, Maximilian; Niemoeller, Olivier M; Li, Minglun; Roeder, Falk; Eckel, Renate; Schubert-Fritschle, Gabriele; Scheithauer, Heike R; Harbeck, Nadia; Engel, Jutta; Belka, Claus

    2015-01-01

    The purpose of this retrospective outcome study was to validate the effectiveness of postoperative radiotherapy in breast conserving therapy (BCT) and to evaluate possible causes for omission of radiotherapy after breast conserving surgery (BCS) in a non-trial population. Data were provided by the population-based Munich Cancer Registry. The study included epidemiological data of 30.811 patients diagnosed with breast cancer from 1998 to 2012. The effect of omitting radiotherapy was analysed using Kaplan-Meier-estimates and Cox proportional hazard regression. Variables predicting omission of radiotherapy were analysed using multivariate logistic regression. Use of postoperative radiotherapy after BCS was associated with significant improvements in local control and survival. 10-year loco-regional recurrence-free-survival was 90.8% with postoperative radiotherapy vs. 77.6% with surgery alone (p<0.001). 10-year overall survival rates were 55.2% with surgery alone vs. 82.2% following postoperative radiotherapy (p<0.001). Variables predicting omission of postoperative radiotherapy included advanced age (women ⩾80 years; OR: 0.082; 95% CI: 0.071-0.094, p<0.001). This study shows a decrease in local control and a survival disadvantage if postoperative radiotherapy after breast conserving surgery is omitted in an unselected cohort of primary breast cancer patients. Due to its epidemiological nature, it cannot answer the question in whom postoperative radiotherapy can be safely omitted. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  5. Radiotherapy in poor risk patients with stage I cancer of the endometrium: results of not giving external beam radiotherapy.

    PubMed

    DeCruze, B; Guthrie, D

    1999-01-01

    Poor prognosis (poorly differentiated and/or deep myometrial invasion) Stage I endometrial cancer can have a relapse rate as high as 50%. Traditionally, most clinical oncologists treat these patients with external beam radiotherapy after surgery but there is no evidence to show that this improves survival. The retrospective study looks at the results of not giving external beam radiotherapy in 25 consecutive patients and compares the results with a group of 13 consecutive patients who did have such treatment. The two groups were comparable with regard to age, degree of differentiation and degree of invasion. Survival was comparable in the two groups. There is no evidence of any obvious decrease in survival from withholding external beam radiotherapy, but this was not a prospective randomized controlled trial. This study illustrates that it is essential that the Medical Research Council ASTEC trial should be supported because this will determine the true place of external beam radiotherapy in such patients.

  6. Vaginal dilator therapy for women receiving pelvic radiotherapy.

    PubMed

    Miles, Tracie; Johnson, Nick

    2014-09-08

    Vaginal dilation therapy is advocated after pelvic radiotherapy to prevent stenosis (abnormal narrowing of the vagina), but can be uncomfortable and psychologically distressing. To assess the benefits and harms of different types of vaginal dilation methods offered to women treated by pelvic radiotherapy for cancer. Searches included the Cochrane Central Register of Controlled Trials (CENTRAL 2013, Issue 5), MEDLINE (1950 to June week 2, 2013), EMBASE (1980 to 2013 week 24) and CINAHL (1982 to 2013). Comparative data of any type, which evaluated dilation or penetration of the vagina after pelvic radiotherapy treatment for cancer. Two review authors independently assessed whether potentially relevant studies met the inclusion criteria. We found no trials and therefore analysed no data. We identified no studies for inclusion in the original review or for this update. However, we felt that some studies that were excluded warranted discussion. These included one randomised trial (RCT), which showed no improvement in sexual scores associated with encouraging women to practise dilation therapy; a recent small RCT that did not show any advantage to dilation over vibration therapy during radiotherapy; two non-randomised comparative studies; and five correlation studies. One of these showed that objective measurements of vaginal elasticity and length were not linked to dilation during radiotherapy, but the study lacked power. One study showed that women who dilated tolerated a larger dilator, but the risk of objectivity and bias with historical controls was high. Another study showed that the vaginal measurements increased in length by a mean of 3 cm after dilation was introduced 6 to 10 weeks after radiotherapy, but there was no control group; another case series showed the opposite. Three recent studies showed less stenosis associated with prophylactic dilation after radiotherapy. One small case series suggested that dilation years after radiotherapy might restore the

  7. Feasibility and Acute Toxicity of Hypofractionated Radiation in Large-breasted Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dorn, Paige L., E-mail: pdorn@radonc.uchicago.edu; Corbin, Kimberly S.; Al-Hallaq, Hania

    Purpose: To determine the feasibility of and acute toxicity associated with hypofractionated whole breast radiation (HypoRT) after breast-conserving surgery in patients excluded from or underrepresented in randomized trials comparing HypoRT with conventional fractionation schedules. Methods and Materials: A review was conducted of all patients consecutively treated with HypoRT at University of Chicago. All patients were treated to 42.56 Gy in 2.66 Gy daily fractions in either the prone or supine position. Planning was performed in most cases using wedges and large segments or a 'field-in-field' technique. Breast volume was estimated using volumetric measurements of the planning target volume (PTV). Dosimetricmore » parameters of heterogeneity (V105, V107, V110, and maximum dose) were recorded for each treatment plan. Acute toxicity was scored for each treated breast. Results: Between 2006 and 2010, 78 patients were treated to 80 breasts using HypoRT. Most women were overweight or obese (78.7%), with a median body mass index of 29.2 kg/m{sup 2}. Median breast volume was 1,351 mL. Of the 80 treated breasts, the maximum acute skin toxicity was mild erythema or hyperpigmentation in 70.0% (56/80), dry desquamation in 21.25% (17/80), and focal moist desquamation in 8.75% (7/80). Maximum acute toxicity occurred after the completion of radiation in 31.9% of patients. Separation >25 cm was not associated with increased toxicity. Breast volume was the only patient factor significantly associated with moist desquamation on multivariable analysis (p = 0.01). Patients with breast volume >2,500 mL experienced focal moist desquamation in 27.2% of cases compared with 6.34% in patients with breast volume <2,500 mL (p = 0.03). Conclusions: HypoRT is feasible and safe in patients with separation >25 cm and in patients with large breast volume when employing modern planning and positioning techniques. We recommend counseling regarding expected increases in skin toxicity in women

  8. Oral mucosal melanoma treated with carbon ion radiotherapy: a case report.

    PubMed

    Musha, Atsushi; Saitoh, Jun-Ichi; Shirai, Katsuyuki; Yokoo, Satoshi; Ohno, Tatsuya; Nakano, Takashi

    2016-10-18

    Oral mucosal melanoma is a rare disease with a relatively poor prognosis. Carbon ion radiotherapy has been shown to be effective against radiotherapy-resistant tumors owing to its excellent dose concentration and high biological effect. Our patient was a 66-year-old Japanese man with oral mucosal melanoma of his right maxillary gingiva (T4aN0M0). He received carbon ion radiotherapy at 57.6 Gy (relative biological effectiveness) in 16 fractions for 4 weeks. Concomitant chemotherapy (dacarbazine + nimustine + vincristine) was administered at the same time as carbon ion radiotherapy initiation. Two courses of adjuvant chemotherapy were given after carbon ion radiotherapy. Although he experienced grade 2 acute oral mucositis, his symptoms improved within a few weeks of undergoing carbon ion radiotherapy. He was alive at the time of reporting, 35 months after treatment, without any recurrence. Late toxicity has not been observed. Carbon ion radiotherapy for oral mucosal melanoma resulted in a good local effect.

  9. Image-guided radiation therapy for liver tumors: gastrointestinal histology matters.

    PubMed

    Katsoulakis, Evangelia; Riaz, Nadeem; Cannon, Donald M; Goodman, Karyn; Spratt, Daniel E; Lovelock, Michael; Yamada, Yoshiya

    2014-12-01

    To describe the safety and efficacy of single-fraction and hypofractionated image-guided radiotherapy techniques for the treatment of large liver tumors. Forty-six patients, with 50 tumors (10 primary liver tumors, 40 liver metastases) from March 2004 to March 2011 were reviewed. The maximal tumor diameter ranged from 1.2 to 11.3 cm (median, 4.2 cm). Eighty-seven percent of patients received prior systemic chemotherapy. Fifty-nine percent had prior invasive local therapy including surgery, ablation, or embolization. Twenty-five lesions were treated with hypofractionated therapy (24 to 30 Gy in 3 to 5 fractions), whereas 19 received a single fraction (18 or 24 Gy). Local control (LC) was calculated using competing risk analysis. Overall survival was calculated by the Kaplan-Meier method. Median follow-up for all patients was 29.8 months (range, 3 to 46 mo). The median survival was 15.4 months. The 1- and 2-year LC rates were 78% and 75%, respectively. Dose and tumor size had no significant effect on tumor progression. The local progression at 1 and 2 years was 29% and 32% for gastrointestinal (GI) histologies versus 0% for non-GI histologies (P=0.02). Tumor volumes larger than 112 cm correlated with decreased survival (P=0.05). Three patients developed late grade 3 GI stricture or ulceration. Image-guided radiotherapy for liver tumors achieves good rates of LC with minimal toxicity at 1 and 2 years even in patients with large or recurrent disease that has been heavily pretreated. GI histology demonstrated decreased LC rates. Further management strategies should be considered in these patients.

  10. Corrigendum to "Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy".

    PubMed

    Zelyak, Oleksandr; Fallone, B Gino; St-Aubin, Joel

    2018-03-12

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  11. Flattening filter-free accelerators: a report from the AAPM Therapy Emerging Technology Assessment Work Group.

    PubMed

    Xiao, Ying; Kry, Stephen F; Popple, Richard; Yorke, Ellen; Papanikolaou, Niko; Stathakis, Sotirios; Xia, Ping; Huq, Saiful; Bayouth, John; Galvin, James; Yin, Fang-Fang

    2015-05-08

    This report describes the current state of flattening filter-free (FFF) radiotherapy beams implemented on conventional linear accelerators, and is aimed primarily at practicing medical physicists. The Therapy Emerging Technology Assessment Work Group of the American Association of Physicists in Medicine (AAPM) formed a writing group to assess FFF technology. The published literature on FFF technology was reviewed, along with technical specifications provided by vendors. Based on this information, supplemented by the clinical experience of the group members, consensus guidelines and recommendations for implementation of FFF technology were developed. Areas in need of further investigation were identified. Removing the flattening filter increases beam intensity, especially near the central axis. Increased intensity reduces treatment time, especially for high-dose stereotactic radiotherapy/radiosurgery (SRT/SRS). Furthermore, removing the flattening filter reduces out-of-field dose and improves beam modeling accuracy. FFF beams are advantageous for small field (e.g., SRS) treatments and are appropriate for intensity-modulated radiotherapy (IMRT). For conventional 3D radiotherapy of large targets, FFF beams may be disadvantageous compared to flattened beams because of the heterogeneity of FFF beam across the target (unless modulation is employed). For any application, the nonflat beam characteristics and substantially higher dose rates require consideration during the commissioning and quality assurance processes relative to flattened beams, and the appropriate clinical use of the technology needs to be identified. Consideration also needs to be given to these unique characteristics when undertaking facility planning. Several areas still warrant further research and development. Recommendations pertinent to FFF technology, including acceptance testing, commissioning, quality assurance, radiation safety, and facility planning, are presented. Examples of clinical

  12. Barriers to radiotherapy access at the University College Hospital in Ibadan, Nigeria.

    PubMed

    Anakwenze, Chidinma P; Ntekim, Atara; Trock, Bruce; Uwadiae, Iyobosa B; Page, Brandi R

    2017-08-01

    Nigeria has the biggest gap between radiotherapy availability and need, with one machine per 19.4 million people, compared to one machine per 250,000 people in high-income countries. This study aims to identify its patient-level barriers to radiotherapy access. This was a cross sectional study consisting of patient questionnaires ( n  = 50) conducted in January 2016 to assess patient demographics, types of cancers seen, barriers to receiving radiotherapy, health beliefs and practices, and factors leading to treatment delay. Eighty percent of patients could not afford radiotherapy without financial assistance and only 6% of the patients had federal insurance, which did not cover radiotherapy services. Of the patients who had completed radiotherapy treatment, 91.3% had experienced treatment delay or often cancellation due to healthcare worker strike, power failure, machine breakdown, or prolonged wait time. The timeliness of a patient's radiotherapy care correlated with their employment status and distance from radiotherapy center ( p  < 0.05). Barriers to care at a radiotherapy center in a low- and middle-income country (LMIC) have previously not been well characterized. These findings can be used to inform efforts to expand the availability of radiotherapy and improve current treatment capacity in Nigeria and in other LMICs.

  13. Bladder filling variation during conformal radiotherapy for rectal cancer

    NASA Astrophysics Data System (ADS)

    Sithamparam, S.; Ahmad, R.; Sabarudin, A.; Othman, Z.; Ismail, M.

    2017-05-01

    Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients.

  14. Cost-effectiveness of modern radiotherapy techniques in locally advanced pancreatic cancer.

    PubMed

    Murphy, James D; Chang, Daniel T; Abelson, Jon; Daly, Megan E; Yeung, Heidi N; Nelson, Lorene M; Koong, Albert C

    2012-02-15

    Radiotherapy may improve the outcome of patients with pancreatic cancer but at an increased cost. In this study, the authors evaluated the cost-effectiveness of modern radiotherapy techniques in the treatment of locally advanced pancreatic cancer. A Markov decision-analytic model was constructed to compare the cost-effectiveness of 4 treatment regimens: gemcitabine alone, gemcitabine plus conventional radiotherapy, gemcitabine plus intensity-modulated radiotherapy (IMRT); and gemcitabine with stereotactic body radiotherapy (SBRT). Patients transitioned between the following 5 health states: stable disease, local progression, distant failure, local and distant failure, and death. Health utility tolls were assessed for radiotherapy and chemotherapy treatments and for radiation toxicity. SBRT increased life expectancy by 0.20 quality-adjusted life years (QALY) at an increased cost of $13,700 compared with gemcitabine alone (incremental cost-effectiveness ratio [ICER] = $69,500 per QALY). SBRT was more effective and less costly than conventional radiotherapy and IMRT. An analysis that excluded SBRT demonstrated that conventional radiotherapy had an ICER of $126,800 per QALY compared with gemcitabine alone, and IMRT had an ICER of $1,584,100 per QALY compared with conventional radiotherapy. A probabilistic sensitivity analysis demonstrated that the probability of cost-effectiveness at a willingness to pay of $50,000 per QALY was 78% for gemcitabine alone, 21% for SBRT, 1.4% for conventional radiotherapy, and 0.01% for IMRT. At a willingness to pay of $200,000 per QALY, the probability of cost-effectiveness was 73% for SBRT, 20% for conventional radiotherapy, 7% for gemcitabine alone, and 0.7% for IMRT. The current results indicated that IMRT in locally advanced pancreatic cancer exceeds what society considers cost-effective. In contrast, combining gemcitabine with SBRT increased clinical effectiveness beyond that of gemcitabine alone at a cost potentially acceptable by

  15. Accelerating an Ordered-Subset Low-Dose X-Ray Cone Beam Computed Tomography Image Reconstruction with a Power Factor and Total Variation Minimization.

    PubMed

    Huang, Hsuan-Ming; Hsiao, Ing-Tsung

    2016-01-01

    In recent years, there has been increased interest in low-dose X-ray cone beam computed tomography (CBCT) in many fields, including dentistry, guided radiotherapy and small animal imaging. Despite reducing the radiation dose, low-dose CBCT has not gained widespread acceptance in routine clinical practice. In addition to performing more evaluation studies, developing a fast and high-quality reconstruction algorithm is required. In this work, we propose an iterative reconstruction method that accelerates ordered-subsets (OS) reconstruction using a power factor. Furthermore, we combine it with the total-variation (TV) minimization method. Both simulation and phantom studies were conducted to evaluate the performance of the proposed method. Results show that the proposed method can accelerate conventional OS methods, greatly increase the convergence speed in early iterations. Moreover, applying the TV minimization to the power acceleration scheme can further improve the image quality while preserving the fast convergence rate.

  16. Accelerating an Ordered-Subset Low-Dose X-Ray Cone Beam Computed Tomography Image Reconstruction with a Power Factor and Total Variation Minimization

    PubMed Central

    Huang, Hsuan-Ming; Hsiao, Ing-Tsung

    2016-01-01

    In recent years, there has been increased interest in low-dose X-ray cone beam computed tomography (CBCT) in many fields, including dentistry, guided radiotherapy and small animal imaging. Despite reducing the radiation dose, low-dose CBCT has not gained widespread acceptance in routine clinical practice. In addition to performing more evaluation studies, developing a fast and high-quality reconstruction algorithm is required. In this work, we propose an iterative reconstruction method that accelerates ordered-subsets (OS) reconstruction using a power factor. Furthermore, we combine it with the total-variation (TV) minimization method. Both simulation and phantom studies were conducted to evaluate the performance of the proposed method. Results show that the proposed method can accelerate conventional OS methods, greatly increase the convergence speed in early iterations. Moreover, applying the TV minimization to the power acceleration scheme can further improve the image quality while preserving the fast convergence rate. PMID:27073853

  17. Children Undergoing Radiotherapy: Swedish Parents’ Experiences and Suggestions for Improvement

    PubMed Central

    Mullaney, Tara; Nilsson, Kristina; Wickart-Johansson, Gun; Svärd, Anna-Maja; Nyholm, Tufve; Lindh, Jack; Lindh, Viveca

    2015-01-01

    Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80–90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child’s and the parent’s view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents’ experience when their child undergoes radiotherapy treatment, and to report parents’ suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2–16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people’s lives upside down, affecting the entire family. Further, the parents experience the child’s suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process. PMID:26509449

  18. Calculation of out-of-field dose distribution in carbon-ion radiotherapy by Monte Carlo simulation.

    PubMed

    Yonai, Shunsuke; Matsufuji, Naruhiro; Namba, Masao

    2012-08-01

    Recent radiotherapy technologies including carbon-ion radiotherapy can improve the dose concentration in the target volume, thereby not only reducing side effects in organs at risk but also the secondary cancer risk within or near the irradiation field. However, secondary cancer risk in the low-dose region is considered to be non-negligible, especially for younger patients. To achieve a dose estimation of the whole body of each patient receiving carbon-ion radiotherapy, which is essential for risk assessment and epidemiological studies, Monte Carlo simulation plays an important role because the treatment planning system can provide dose distribution only in∕near the irradiation field and the measured data are limited. However, validation of Monte Carlo simulations is necessary. The primary purpose of this study was to establish a calculation method using the Monte Carlo code to estimate the dose and quality factor in the body and to validate the proposed method by comparison with experimental data. Furthermore, we show the distributions of dose equivalent in a phantom and identify the partial contribution of each radiation type. We proposed a calculation method based on a Monte Carlo simulation using the PHITS code to estimate absorbed dose, dose equivalent, and dose-averaged quality factor by using the Q(L)-L relationship based on the ICRP 60 recommendation. The values obtained by this method in modeling the passive beam line at the Heavy-Ion Medical Accelerator in Chiba were compared with our previously measured data. It was shown that our calculation model can estimate the measured value within a factor of 2, which included not only the uncertainty of this calculation method but also those regarding the assumptions of the geometrical modeling and the PHITS code. Also, we showed the differences in the doses and the partial contributions of each radiation type between passive and active carbon-ion beams using this calculation method. These results indicated that

  19. Radiotherapy access in Belgium: How far are we from evidence-based utilisation?

    PubMed

    Lievens, Y; De Schutter, H; Stellamans, K; Rosskamp, M; Van Eycken, L

    2017-10-01

    Underutilisation of radiotherapy has been observed worldwide. To evaluate the current situation in Belgium, optimal utilisation proportions (OUPs) adopted from the European SocieTy for Radiotherapy and Oncology - Health Economics in Radiation Oncology (ESTRO-HERO) project were compared to actual utilisation proportions (AUPs) and with radiotherapy advised during the multidisciplinary cancer team (MDT) meetings. In addition, the impact of independent variables was analysed. AUPs and advised radiotherapy were calculated overall and by cancer type for 110,810 unique cancer diagnoses in 2009-2010. Radiotherapy utilisation was derived from reimbursement data and distinguished between palliative and curative intent external beam radiotherapy (EBRT) and/or brachytherapy (BT). Sensitivity analyses regarding the influence of the follow-up period, the survival length and patient's age were performed. Advised radiotherapy was calculated based on broad treatment categories as reported at MDT meetings. The overall AUP of 37% (39% including BT) was lower than the OUP of 53%, but in line with advised radiotherapy (35%). Large variations by tumour type were observed: in some tumours (e.g. lung and prostate cancer) AUP was considerably lower than OUP, whereas in others there was reasonable concordance (e.g. breast and rectal cancer). Overall, 84% of treatments started within 9 months following diagnosis. Survival time influenced AUP in a cancer type-dependent way. Elderly patients received less radiotherapy. Although the actually delivered radiotherapy in Belgium aligns well to MDT advices, it is lower than the evidence-based optimum. Further analysis of potential barriers is needed for radiotherapy forecasting and planning, and in order to promote adequate access to radiotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Commissioning of a conformal irradiation system for heavy-ion radiotherapy using a layer-stacking method.

    PubMed

    Kanai, Tatsuaki; Kanematsu, Nobuyuki; Minohara, Shinichi; Komori, Masataka; Torikoshi, Masami; Asakura, Hiroshi; Ikeda, Noritoshi; Uno, Takayuki; Takei, Yuka

    2006-08-01

    The commissioning of conformal radiotherapy system using heavy-ion beams at the Heavy Ion Medical Accelerator in Chiba (HIMAC) is described in detail. The system at HIMAC was upgraded for a clinical trial using a new technique: large spot uniform scanning with conformal layer stacking. The system was developed to localize the irradiation dose to the target volume more effectively than with the old system. With the present passive irradiation method using a ridge filter, a scatterer, a pair of wobbler magnets, and a multileaf collimator, the width of the spread-out Bragg peak (SOBP) in the radiation field could not be changed. With dynamic control of the beam-modifying devices during irradiation, a more conformal radiotherapy could be achieved. In order to safely perform treatments with this conformal therapy, the moving devices should be watched during irradiation and the synchronousness among the devices should be verified. This system, which has to be safe for patient irradiations, was constructed and tested for safety and for the quality of the dose localization realized. Through these commissioning tests, we were successfully able to prepare the conformal technique using layer stacking for patients. Subsequent to commissioning the technique has been applied to patients in clinical trials.

  1. Radiotherapy in the treatment of solitary plasmacytoma.

    PubMed

    Jyothirmayi, R; Gangadharan, V P; Nair, M K; Rajan, B

    1997-05-01

    Solitary plasmacytoma of bone (SPB) and extramedullary plasmacytoma (EMP) are rare. High local control rates are reported with radiotherapy, although the optimal dose and extent of radiotherapy portals remains controversial. Between 1983 and 1993, 30 patients with solitary plasmacytoma were seen at the Regional Cancer Centre, Trivandrum, India. 23 patients had SPB and seven EMP. The mean age was 52 years and the male to female ratio 3.2:1. Diagnosis of SPB was confirmed by biopsy in 16 patients and tumour excision in seven. 20 patients received megavoltage radiotherapy to the bone lesion with limited margins, and one received chemotherapy. Two patients who underwent complete tumour excision received no further treatment. All seven patients with EMP received megavoltage radiotherapy, four following biopsy and three after tumour excision. Local control was achieved in all patients with SPB. Nine progressed to multiple myeloma and one developed a solitary plasmacytoma in another bone. Six patients with EMP achieved local control. Three later progressed to multiple myeloma and one had local relapse. Median time to relapse was 28 months in SPB and 30 months in EMP. 5-year overall survival rates were 82% and 57% for patients with SPB and EMP, respectively. The corresponding progression free survival rates were 55% and 50%, respectively. Age, sex, site of tumour, serum M protein and haemoglobin levels did not significantly influence progression free survival. The extent of surgery, radiotherapy dose or time to relapse were not significant prognostic factors. Radiotherapy appears to be an effective modality of treatment of solitary plasmacytoma. No dose-response relationship is observed, and high local control rates are achieved with limited portals. Progression to multiple myeloma is the commonest pattern of failure, although no prognostic factors for progression are identified. The role of chemotherapy in preventing disease progression needs further evaluation.

  2. New concept on an integrated interior magnetic resonance imaging and medical linear accelerator system for radiation therapy.

    PubMed

    Jia, Xun; Tian, Zhen; Xi, Yan; Jiang, Steve B; Wang, Ge

    2017-01-01

    Image guidance plays a critical role in radiotherapy. Currently, cone-beam computed tomography (CBCT) is routinely used in clinics for this purpose. While this modality can provide an attenuation image for therapeutic planning, low soft-tissue contrast affects the delineation of anatomical and pathological features. Efforts have recently been devoted to several MRI linear accelerator (LINAC) projects that lead to the successful combination of a full diagnostic MRI scanner with a radiotherapy machine. We present a new concept for the development of the MRI-LINAC system. Instead of combining a full MRI scanner with the LINAC platform, we propose using an interior MRI (iMRI) approach to image a specific region of interest (RoI) containing the radiation treatment target. While the conventional CBCT component still delivers a global image of the patient's anatomy, the iMRI offers local imaging of high soft-tissue contrast for tumor delineation. We describe a top-level system design for the integration of an iMRI component into an existing LINAC platform. We performed numerical analyses of the magnetic field for the iMRI to show potentially acceptable field properties in a spherical RoI with a diameter of 15 cm. This field could be shielded to a sufficiently low level around the LINAC region to avoid electromagnetic interference. Furthermore, we investigate the dosimetric impacts of this integration on the radiotherapy beam.

  3. Current State Of Proton And Carbon-Ion Radiotherapy At The Hyogo Ion Beam Medical Center (HIBMC)

    NASA Astrophysics Data System (ADS)

    Murakami, Masao; Demizu, Yusuke; Niwa, Yasue; Fujii, Osamu; Terashima, Kazuki; Mima, Masayuki; Miyawaki, Daisuke; Sasaki, Ryohei; Hishikawa, Yoshio; Abe, Mitsuyuki

    2011-06-01

    HIBMC is the world's first facility to be able to use both proton (PRT) and carbon-ion radiotherapy (CiRT). The medically dedicated synchrotron can accelerate protons up to 230 MeV and carbon ions up to 320 MeV. From April 2001 to March 2010, the facility treated 3275 patients, with 2487 patients treated using PRT and 788 using CiRT. Particle radiotherapy was delivered to patients suffering from malignant tumors originating in the head and neck (502 patients), lungs (330), liver (539), prostate (1283), and the bone & soft tissue (130). The clinical results are as follows: (1) H & N tumors: The 2-year overall survival (OS) rates of patients with olfactory neuroblastoma, mucoepidermoid cancer, adenoid cystic cancer, adenocarcinoma, squamous cell carcinoma, and malignant melanoma was 100%, 86%, 78%, 78%, 66%, and 62%, respectively. (2) Lung cancer: For all 80 patients, the 3-year OS rate was 75% (Stage IA: 74%; Stage IB: 76%) and local control (LC) rate was 82% (IA: 87%; IB: 77%). Grade 3 pulmonary toxicity was observed in only 1 patient. These results are comparable to those obtained by surgery, and indicate proton therapy and carbon-ion therapy are safe and effective for stage I lung cancer. (3) Liver cancer: The 5-year LC rate for 429 tumor patient was 90%, and the 5-year OS rate for 364 patients was 38%. These results seem equivalent to those obtained by surgery or radio-frequency ablation. (4) Prostate cancer: In 290 patients treated by proton radiotherapy, five patients died from other disease in the median follow-up period of 62 months. Biochemical disease-free survival and OS rate at 5 years was 88.2% and 96.5%, respectively. Our proton radiotherapy showed excellent OS and biochemical disease-free survival rates with minimum late morbidities. PRT VS CiRT: From our retrospective analysis, it seems that there is no significant difference in the LC and OS rate in H&N, lung and liver cancer between PRT and CiRT.

  4. Current State Of Proton And Carbon-Ion Radiotherapy At The Hyogo Ion Beam Medical Center (HIBMC)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murakami, Masao; Hishikawa, Yoshio; Demizu, Yusuke

    2011-06-01

    HIBMC is the world's first facility to be able to use both proton (PRT) and carbon-ion radiotherapy (CiRT). The medically dedicated synchrotron can accelerate protons up to 230 MeV and carbon ions up to 320 MeV. From April 2001 to March 2010, the facility treated 3275 patients, with 2487 patients treated using PRT and 788 using CiRT. Particle radiotherapy was delivered to patients suffering from malignant tumors originating in the head and neck (502 patients), lungs (330), liver (539), prostate (1283), and the bone and soft tissue (130). The clinical results are as follows: (1) H and N tumors: Themore » 2-year overall survival (OS) rates of patients with olfactory neuroblastoma, mucoepidermoid cancer, adenoid cystic cancer, adenocarcinoma, squamous cell carcinoma, and malignant melanoma was 100%, 86%, 78%, 78%, 66%, and 62%, respectively. (2) Lung cancer: For all 80 patients, the 3-year OS rate was 75%(Stage IA: 74%; Stage IB: 76%) and local control (LC) rate was 82%(IA: 87%; IB: 77%). Grade 3 pulmonary toxicity was observed in only 1 patient. These results are comparable to those obtained by surgery, and indicate proton therapy and carbon-ion therapy are safe and effective for stage I lung cancer. (3) Liver cancer: The 5-year LC rate for 429 tumor patient was 90%, and the 5-year OS rate for 364 patients was 38%. These results seem equivalent to those obtained by surgery or radio-frequency ablation. (4) Prostate cancer: In 290 patients treated by proton radiotherapy, five patients died from other disease in the median follow-up period of 62 months. Biochemical disease-free survival and OS rate at 5 years was 88.2% and 96.5%, respectively. Our proton radiotherapy showed excellent OS and biochemical disease-free survival rates with minimum late morbidities. PRT VS CiRT: From our retrospective analysis, it seems that there is no significant difference in the LC and OS rate in H and N, lung and liver cancer between PRT and CiRT.« less

  5. Second cancer incidence risk estimates using BEIR VII models for standard and complex external beam radiotherapy for early breast cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Donovan, E. M.; James, H.; Bonora, M.

    2012-10-15

    Purpose: To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy (including cone beam CT verification) following breast conservation surgery for early breast cancer.Method: Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated: (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, and (v) inverse-planned three volume SIB.more » Conformal and intensity modulated radiotherapy methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contralateral breast, left and right lung, esophagus, stomach, liver, colon, and bladder. Biological Effects of Ionizing Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine lifetime attributable risk (LAR) for ages at exposure from 35 to 80 yr according to radiotherapy techniques, and included dose from the CBCT imaging. Results: All LAR decreased with age at exposure and were lowest for brain, thyroid, liver, and bladder (<0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods

  6. [Head and neck adaptive radiotherapy].

    PubMed

    Graff, P; Huger, S; Kirby, N; Pouliot, J

    2013-10-01

    Onboard volumetric imaging systems can provide accurate data of the patient's anatomy during a course of head and neck radiotherapy making it possible to assess the actual delivered dose and to evaluate the dosimetric impact of complex daily positioning variations and gradual anatomic changes such as geometric variations of tumors and normal tissues or shrinkage of external contours. Adaptive radiotherapy is defined as the correction of a patient's treatment planning to adapt for individual variations observed during treatment. Strategies are developed to selectively identify patients that require replanning because of an intolerable dosimetric drift. Automated tools are designed to limit time consumption. Deformable image registration algorithms are the cornerstones of these strategies, but a better understanding of their limits of validity is required before adaptive radiotherapy can be safely introduced to daily practice. Moreover, strict evaluation of the clinical benefits is yet to be proven. Copyright © 2013 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  7. Recent Advances in Image-Guided Radiotherapy for Head and Neck Carcinoma

    PubMed Central

    Nath, Sameer K.; Simpson, Daniel R.; Rose, Brent S.; Sandhu, Ajay P.

    2009-01-01

    Radiotherapy has a well-established role in the management of head and neck cancers. Over the past decade, a variety of new imaging modalities have been incorporated into the radiotherapy planning and delivery process. These technologies are collectively referred to as image-guided radiotherapy and may lead to significant gains in tumor control and radiation side effect profiles. In the following review, these techniques as they are applied to head and neck cancer patients are described, and clinical studies analyzing their use in target delineation, patient positioning, and adaptive radiotherapy are highlighted. Finally, we conclude with a brief discussion of potential areas of further radiotherapy advancement. PMID:19644564

  8. A Kindler syndrome-associated squamous cell carcinoma treated with radiotherapy.

    PubMed

    Caldeira, Ademar; Trinca, William Correia; Flores, Thais Pires; Costa, Andrea Barleze; Brito, Claudio de Sá; Weigert, Karen Loureiro; Matos, Maryana Schwartzhaupt; Nicolini, Carmela; Obst, Fernando Mariano

    2016-01-01

    Kindler syndrome1, 2 is a genetic disorder mainly characterized by increased skin fragility and photosensitivity,3, 4 making the use of treatments based on radiation difficult or even prohibited. Thus, cases reporting Kindler syndrome patients treated with radiotherapy are rare. In this study, we report clinical outcomes and care provided for a rare case of a Kindler syndrome patient submitted to radiotherapy. Diagnosed with squamous cell carcinoma involving the buccal mucosa, the patient was exclusively treated with radiotherapy, with 70 Gy delivered on the PTV with the Volumetric Modulated Arc technique. The patient's reaction regarding control of the lesion is relevant compared to patients not affected by the syndrome. We noticed acute reactions of the skin and buccal mucosa after few radiotherapy sessions, followed by a fast reduction in the tumor volume. The efficacy of radiotherapy along with multidisciplinary actions allowed treatment continuity, leading to a complete control of the lesion and life quality improvement and showed that the use of radiotherapy on Kindler syndrome patients is possible.

  9. The feasibility of using Microsoft Kinect v2 sensors during radiotherapy delivery.

    PubMed

    Edmunds, David M; Bashforth, Sophie E; Tahavori, Fatemeh; Wells, Kevin; Donovan, Ellen M

    2016-11-08

    Consumer-grade distance sensors, such as the Microsoft Kinect devices (v1 and v2), have been investigated for use as marker-free motion monitoring systems for radiotherapy. The radiotherapy delivery environment is challenging for such sen-sors because of the proximity to electromagnetic interference (EMI) from the pulse forming network which fires the magnetron and electron gun of a linear accelerator (linac) during radiation delivery, as well as the requirement to operate them from the control area. This work investigated whether using Kinect v2 sensors as motion monitors was feasible during radiation delivery. Three sensors were used each with a 12 m USB 3.0 active cable which replaced the supplied 3 m USB 3.0 cable. Distance output data from the Kinect v2 sensors was recorded under four condi-tions of linac operation: (i) powered up only, (ii) pulse forming network operating with no radiation, (iii) pulse repetition frequency varied between 6 Hz and 400 Hz, (iv) dose rate varied between 50 and 1450 monitor units (MU) per minute. A solid water block was used as an object and imaged when static, moved in a set of steps from 0.6 m to 2.0 m from the sensor and moving dynamically in two sinusoidal-like trajectories. Few additional image artifacts were observed and there was no impact on the tracking of the motion patterns (root mean squared accuracy of 1.4 and 1.1mm, respectively). The sensors' distance accuracy varied by 2.0 to 3.8 mm (1.2 to 1.4 mm post distance calibration) across the range measured; the precision was 1 mm. There was minimal effect from the EMI on the distance calibration data: 0 mm or 1 mm reported distance change (2 mm maximum change at one position). Kinect v2 sensors operated with 12 m USB 3.0 active cables appear robust to the radiotherapy treatment environment. © 2016 The Authors.

  10. Dosimetry in radiotherapy using a-Si EPIDs: Systems, methods, and applications focusing on 3D patient dose estimation

    NASA Astrophysics Data System (ADS)

    McCurdy, B. M. C.

    2013-06-01

    An overview is provided of the use of amorphous silicon electronic portal imaging devices (EPIDs) for dosimetric purposes in radiation therapy, focusing on 3D patient dose estimation. EPIDs were originally developed to provide on-treatment radiological imaging to assist with patient setup, but there has also been a natural interest in using them as dosimeters since they use the megavoltage therapy beam to form images. The current generation of clinically available EPID technology, amorphous-silicon (a-Si) flat panel imagers, possess many characteristics that make them much better suited to dosimetric applications than earlier EPID technologies. Features such as linearity with dose/dose rate, high spatial resolution, realtime capability, minimal optical glare, and digital operation combine with the convenience of a compact, retractable detector system directly mounted on the linear accelerator to provide a system that is well-suited to dosimetric applications. This review will discuss clinically available a-Si EPID systems, highlighting dosimetric characteristics and remaining limitations. Methods for using EPIDs in dosimetry applications will be discussed. Dosimetric applications using a-Si EPIDs to estimate three-dimensional dose in the patient during treatment will be overviewed. Clinics throughout the world are implementing increasingly complex treatments such as dynamic intensity modulated radiation therapy and volumetric modulated arc therapy, as well as specialized treatment techniques using large doses per fraction and short treatment courses (ie. hypofractionation and stereotactic radiosurgery). These factors drive the continued strong interest in using EPIDs as dosimeters for patient treatment verification.

  11. Combinations of Radiotherapy and Immunotherapy for Melanoma: A Review of Clinical Outcomes

    PubMed Central

    Barker, Christopher A.; Postow, Michael A.

    2015-01-01

    Radiotherapy has long played a role in the management of melanoma. Recent advances have also demonstrated the efficacy of immunotherapy in the treatment of melanoma. Preclinical data suggest a biologic interaction between radiotherapy and immunotherapy. Several clinical studies corroborate these findings. This review will summarize the outcomes of studies reporting on patients with melanoma treated with a combination of radiotherapy and immunotherapy. Vaccine therapies often use irradiated melanoma cells, and may be enhanced by radiotherapy. The cytokines interferon-alpha and interleukin-2 have been combined with radiotherapy in several small studies, with some evidence suggesting increased toxicity and/or efficacy. Ipilimumab, a monoclonal antibody which blocks cytotoxic T-lymphocyte antigen-4, has been combined with radiotherapy in several notable case studies and series. Finally, pilot studies of adoptive cell transfer have suggested radiotherapy may improve the efficacy of treatment. The review will demonstrate that the combination of radiotherapy and immunotherapy has been reported in several notable case studies, series and clinical trials. These clinical results suggest interaction and the need for further study. PMID:24661650

  12. Postoperative Radiotherapy Patterns of Care and Survival Implications for Medulloblastoma in Young Children.

    PubMed

    Kann, Benjamin H; Park, Henry S; Lester-Coll, Nataniel H; Yeboa, Debra N; Benitez, Viviana; Khan, Atif J; Bindra, Ranjit S; Marks, Asher M; Roberts, Kenneth B

    2016-12-01

    Postoperative radiotherapy to the craniospinal axis is standard-of-care for pediatric medulloblastoma but is associated with long-term morbidity, particularly in young children. With the advent of modern adjuvant chemotherapy strategies, postoperative radiotherapy deferral has gained acceptance in children younger than 3 years, although it remains controversial in older children. To analyze recent postoperative radiotherapy national treatment patterns and implications for overall survival in patients with medulloblastoma ages 3 to 8 years. Using the National Cancer Data Base, patients ages 3 to 8 years diagnosed as having histologically confirmed medulloblastoma in 2004 to 2012, without distant metastases, who underwent surgery and adjuvant chemotherapy with or without postoperative radiotherapy at facilities nationwide accredited by the Commission on Cancer were identified. Patients were designated as having "postoperative radiotherapy upfront" if they received radiotherapy within 90 days of surgery or "postoperative radiotherapy deferred" otherwise. Factors associated with postoperative radiotherapy deferral were identified using multivariable logistic regression. Overall survival (OS) was compared using Kaplan-Meier analysis with log-rank tests and multivariable Cox regression. Statistical tests were 2-sided. Postoperative radiotherapy utilization and overall survival. Among 816 patients, 123 (15.1%) had postoperative radiotherapy deferred, and 693 (84.9%) had postoperative radiotherapy upfront; 36.8% of 3-year-olds and 4.1% of 8-year-olds had postoperative radiotherapy deferred (P < .001). On multivariable logistic regression, variables associated with postoperative radiotherapy deferral were age (odds ratio [OR], 0.57 per year; 95% CI, 0.49-0.67 per year) and year of diagnosis (OR, 1.18 per year; 95% CI, 1.08-1.29 per year). On survival analysis, with median follow-up of 4.8 years, OS was improved for those receiving postoperative radiotherapy upfront vs

  13. Secondary malignancy following radiotherapy for thyroid eye disease.

    PubMed

    Gillis, Christopher C; Chang, Eun Hae; Al-Kharazi, Khalid; Pickles, Tom

    2016-01-01

    To describe the first case of a secondary meningioma in a patient after radiation treatment for thyroid eye disease (TED). Secondarily to identify any additional cases of secondary malignancy resulting from radiotherapy for thyroid eye disease from our institutional experience. Thyroid eye disease (TED) is a self-limiting auto-immune disorder causing expansion of orbital soft tissue from deposition of glycosaminoglycans and collagen, leading to significant cosmetic and functional morbidity. Established management options for TED include: glucocorticosteroids, orbital radiotherapy, and surgical orbital decompression. Two large series on radiotherapy for TED have been reported without any cases of secondary malignancy. The case of a patient with visual failure, found to have a sphenoid wing meningioma after previous TED radiotherapy is described. We then reviewed 575 patients with at least 3-year follow-up receiving radiotherapy for TED at British Columbia Cancer Agency to identify other possible secondary malignancies. The patient had postoperative improvement in her vision without any identified complications. Three additional cases of hematologic malignancy were identified. The calculated risk in our population of developing a radiation-induced meningioma after TED with at least 3 years of follow-up of is 0.17% (1/575); with hematopoetic malignancies the risk for secondary malignancy is 0.7% (4/575). Our calculated risk for secondary malignancy (0.17%, 0.7%) is similar to the reported theoretical risk published in the literature (0.3-1.2%). There is real risk for the development of a secondary malignancy after radiotherapy treatment of TED and treatment options should include consideration for this potential.

  14. Outcome in dogs with advanced (stage 3b) anal sac gland carcinoma treated with surgery or hypofractionated radiation therapy.

    PubMed

    Meier, V; Polton, G; Cancedda, S; Roos, M; Laganga, P; Emmerson, T; Rohrer Bley, C

    2017-09-01

    Stage 3b anal sac gland carcinoma (ASGC) can be life-threatening. A surgical approach is not always possible or may be declined. Dogs with stage 3b ASGC treated with surgery or conformal radiation therapy (RT) with 8 × 3.8 Gy (total dose 30.4 Gy, over 2.5 weeks) were retrospectively evaluated. Patient characteristics, median progression-free interval (PFI) and median survival time (MST) were compared. Twenty-eight dogs were included; 15 underwent surgery, 13 underwent RT. At the time of presentation, 21% showed life-threatening obstipation and 25% showed hypercalcaemia. PFI and MST for surgery cases were 159 days (95% CI: 135-184 days) and 182 days (95% CI: 146-218 days), both significantly lower than for RT cases with 347 days (95% CI: 240-454 days) and 447 days (95% CI: 222-672 days), (P = 0.01, P = 0.019). Surgery as well as RT led to a fast relief of symptoms. PFI and survival of surgical patients were significantly inferior to that of a comparable patient group treated with conformal hypofractionated RT. © 2016 John Wiley & Sons Ltd.

  15. History of the development of radiotherapy in Latin America.

    PubMed

    Pinillos, Luis; Pinto, Joseph A; Sarria, Gustavo

    2017-01-01

    Radiotherapy was the first nonsurgical treatment for malignant tumours and represents one of the oldest disciplines of oncology. In Latin America, as in many parts of the world, the history of modern oncology begins with the implementation of radiation therapy facilities. The development of radiotherapy in Latin America was possible thanks to the seminal work of radiation oncologists in different countries. As a large territory, there is a need to implement modern facilities and equipment, but unfortunately there are disparities in the access and quality of radiotherapy services across Latin America and even within individual countries. In this review, we describe the history, challenges and success in the implementation of radiotherapy and the frustration caused by the lack of facilities in several Latin American countries.

  16. External Beam Accelerated Partial Breast Irradiation Yields Favorable Outcomes in Patients with Prior Breast Augmentation

    PubMed Central

    Lei, Rachel Y.; Leonard, Charles E.; Howell, Kathryn T.; Henkenberns, Phyllis L.; Johnson, Timothy K.; Hobart, Tracy L.; Kercher, Jane M.; Widner, Jodi L.; Kaske, Terese; Barke, Lora D.; Carter, Dennis L.

    2014-01-01

    Purpose: To report outcomes in breast cancer patients with prior breast augmentation treated with external beam accelerated partial breast irradiation (EB-APBI) utilizing intensity-modulated radiotherapy or 3-dimensional conformal radiotherapy, both with IGRT. Materials and Methods: Sixteen stage 0/1 breast cancer patients with previous elective bilateral augmentation were treated post-lumpectomy on institutional EB-APBI trials (01185132 and 01185145 on clinicaltrials.gov). Patients received 38.5 Gy in 10 fractions over five consecutive days. Breast/chest wall pain and cosmesis were rated by patient; cosmesis was additionally evaluated by physician per RTOG criteria. Results: The median follow-up from accelerated partial breast irradiation (APBI) completion was 23.9 months (range, 1.2–58.6). Little to no change in cosmesis or pain from baseline was reported. Cosmetic outcomes at last follow-up were judged by patients as excellent/good in 81.2% (13/16), and by physicians as excellent/good in 93.8% (15/16). Ten patients (62.5%) reported no breast/chest wall pain, five (31.2%) reported mild pain, and one (6.2%) reported moderate pain. All patients remain disease free at last follow-up. The median ipsilateral breast, planning target volume (PTV), and implant volumes were 614, 57, and 333 cm3. The median ratios of PTV/ipsilateral breast volume (implant excluded) and PTV/total volume (implant included) were 9 and 6%. Conclusion: These 16 breast cancer cases with prior bilateral augmentation treated with EB-APBI demonstrate favorable clinical outcomes. Further exploration of EB-APBI as a treatment option for this patient population is warranted. PMID:24995159

  17. Microcystic adnexal carcinoma following radiotherapy in childhood

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Borenstein, A.; Seidman, D.S.; Trau, H.

    1991-04-01

    A 36-year-old man was treated by radiotherapy for tinea capitis many years before discovery of microcystic adnexal carcinoma (MAC). Because of patient's refusal of any surgical intervention, we were able to follow the natural course of this tumor for 13 years. This case emphasizes the typical slow development of (MAC). The implication of the association of MAC and radiotherapy are discussed.

  18. [Accelerated partial breast irradiation with image-guided intensity-modulated radiotherapy following breast-conserving surgery - preliminary results of a phase II clinical study].

    PubMed

    Mészáros, Norbert; Major, Tibor; Stelczer, Gábor; Zaka, Zoltán; Mózsa, Emõke; Fodor, János; Polgár, Csaba

    2015-06-01

    The purpose of the study was to implement accelerated partial breast irradiation (APBI) by means of image-guided intensity-modulated radiotherapy (IG-IMRT) following breast-conserving surgery (BCS) for low-risk early invasive breast cancer. Between July 2011 and March 2014, 60 patients with low-risk early invasive (St I-II) breast cancer who underwent BCS were enrolled in our phase II prospective study. Postoperative APBI was given by means of step and shoot IG-IMRT using 4 to 5 fields to a total dose of 36.9 Gy (9×4.1 Gy) using a twice-a-day fractionation. Before each fraction, series of CT images were taken from the region of the target volume using a kV CT on-rail mounted in the treatment room. An image fusion software was used for automatic image registration of the planning and verification CT images. Patient set-up errors were detected in three directions (LAT, LONG, VERT), and inaccuracies were adjusted by automatic movements of the treatment table. Breast cancer related events, acute and late toxicities, and cosmetic results were registered and analysed. At a median follow-up of 24 months (range 12-44) neither locoregional nor distant failure was observed. Grade 1 (G1), G2 erythema, G1 oedema, and G1 and G2 pain occurred in 21 (35%), 2 (3.3%), 23 (38.3%), 6 (10%) and 2 (3.3%) patients, respectively. No G3-4 acute side effects were detected. Among late radiation side effects G1 pigmentation, G1 fibrosis, and G1 fat necrosis occurred in 5 (8.3%), 7 (11.7%), and 2 (3.3%) patients, respectively. No ≥G2 late toxicity was detected. Excellent and good cosmetic outcome was detected in 45 (75%) and 15 (25%) patients. IG-IMRT is a reproducible and feasible technique for the delivery of APBI following conservative surgery for the treatment of low-risk, early-stage invasive breast carcinoma. Preliminary results are promising, early radiation side effects are minimal, and cosmetic results are excellent.

  19. Estimating the number of fractions by tumour site for European countries in 2012 and 2025: An ESTRO-HERO analysis.

    PubMed

    Borras, Josep M; Grau, Cai; Corral, Julieta; Wong, Karen; Barton, Michael B; Ferlay, Jacques; Bray, Freddie; Lievens, Yolande

    2018-02-01

    The optimal number of radiotherapy fractions is a relevant input for planning resource needs. An estimation of the total number of fractions by country and tumour site is assessed for 2012 and 2025. European cancer incidence data by tumour site and country for 2012 and 2025 were extracted from the GLOBOCAN database. Incidence and stage data were introduced in the Australian Collaboration for Cancer Outcomes Research and Evaluation (CCORE) model, producing an evidence-based proportion of incident cases with an indication for radiotherapy and fractions by indication. An indication was defined as a clinical situation in which radiotherapy was the treatment of choice. The total number of fractions if radiotherapy was given according to guidelines to all patients with an indication in Europe was estimated to be 30 million for 2012; with a forecasted increase of 16.1% by 2025, yet with differences by country and tumour. The average number of fractions per course was 17.6 with a small range of differences following stage at diagnosis. Among the treatments with radical intent the average was 24 fractions, while it decreased to 2.5 among palliative treatments. An increase in the total number of fractions is expected in many European countries in the coming years following the trends in cancer incidence. In planning radiotherapy resources, these increases should be balanced to the evolution towards hypofractionation, along with increased complexity and quality assurance. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Radiotherapy for breast cancer: The predictable consequences of an unmet need.

    PubMed

    Rodin, Danielle; Knaul, Felicia M; Lui, Tracey Y; Gospodarowicz, Mary

    2016-10-01

    Radiotherapy has had a transformative impact on the treatment of breast cancer, but is unavailable to the majority of breast cancer patients in low- and middle-income countries. In these settings, where many women present with advanced disease at an age when they are often the primary caregiver for their families, the lack of access to radiotherapy is particularly devastating. Until recently, this disparity has been largely neglected in the medical literature and it had been difficult to convince governments, industry, and policymakers of the importance of investing in radiotherapy, as well as broader cancer control strategies, in low-resource settings. The Lancet Radiotherapy Commission report published in 2015 challenged many assumptions about the affordability of radiotherapy treatment. Data from the Commission is presented here to support radiotherapy investment for breast cancer and discuss how the morbidity and premature mortality among adult women caused by breast cancer has a huge detrimental effect on both the health sector and the economy. Copyright © 2016. Published by Elsevier Ltd.