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Sample records for 3d-conformal radiotherapy 3d-crt

  1. Dosimetric comparison of preoperative single-fraction partial breast radiotherapy techniques: 3D CRT, noncoplanar IMRT, coplanar IMRT, and VMAT.

    PubMed

    Yoo, Sua; Blitzblau, Rachel; Yin, Fang-Fang; Horton, Janet K

    2015-01-08

    The purpose of this study was to compare dosimetric parameters of treatment plans among four techniques for preoperative single-fraction partial breast radiotherapy in order to select an optimal treatment technique. The techniques evaluated were noncoplanar 3D conformal radiation therapy (3D CRT), noncoplanar intensity-modulated radiation therapy (IMRTNC), coplanar IMRT (IMRTCO), and volumetric-modulated arc therapy (VMAT). The planning CT scans of 16 patients in the prone position were used in this study, with the single-fraction prescription doses of 15 Gy for the first eight patients and 18 Gy for the remaining eight patients. Six (6) MV photon beams were designed to avoid the heart and contralateral breast. Optimization for IMRT and VMAT was performed to reduce the dose to the skin and normal breast. All plans were normalized such that 100% of the prescribed dose covered greater than 95% of the clinical target volume (CTV) consisting of gross tumor volume (GTV) plus 1.5 cm margin. Mean homogeneity index (HI) was the lowest (1.05 ± 0.02) for 3D CRT and the highest (1.11 ± 0.04) for VMAT. Mean conformity index (CI) was the lowest (1.42 ± 0.32) for IMRTNC and the highest (1.60 ± 0.32) for VMAT. Mean of the maximum point dose to skin was the lowest (73.7 ± 11.5%) for IMRTNC and the highest (86.5 ± 6.68%) for 3D CRT. IMRTCO showed very similar HI, CI, and maximum skin dose to IMRTNC (differences <1%). The estimated mean treatment delivery time, excluding the time spent for patient positioning and imaging, was 7.0 ± 1.0, 8.3 ± 1.1, 9.7 ± 1.0, and 11.0 ± 1.5min for VMAT, IMRTCO, IMRTNC and 3D CRT, respectively. In comparison of all four techniques for preoperative single-fraction partial breast radiotherapy, we can conclude that noncoplanar or coplanar IMRT were optimal in this study as IMRT plans provided homogeneous and conformal target coverage, skin sparing, and relatively short treatment delivery time.

  2. Clinical Outcome of Patients Treated With 3D Conformal Radiation Therapy (3D-CRT) for Prostate Cancer on RTOG 9406

    SciTech Connect

    Michalski, Jeff; Winter, Kathryn; Roach, Mack; Markoe, Arnold; Sandler, Howard M.; Ryu, Janice; Parliament, Matthew; Purdy, James A.; Valicenti, Richard K.; Cox, James D.

    2012-07-01

    Purpose: Report of clinical cancer control outcomes on Radiation Therapy Oncology Group (RTOG) 9406, a three-dimensional conformal radiation therapy (3D-CRT) dose escalation trial for localized adenocarcinoma of the prostate. Methods and Materials: RTOG 9406 is a Phase I/II multi-institutional dose escalation study of 3D-CRT for men with localized prostate cancer. Patients were registered on five sequential dose levels: 68.4 Gy, 73.8 Gy, 79.2 Gy, 74 Gy, and 78 Gy with 1.8 Gy/day (levels I-III) or 2.0 Gy/day (levels IV and V). Neoadjuvant hormone therapy (NHT) from 2 to 6 months was allowed. Protocol-specific, American Society for Therapeutic Radiation Oncology (ASTRO), and Phoenix biochemical failure definitions are reported. Results: Thirty-four institutions enrolled 1,084 patients and 1,051 patients are analyzable. Median follow-up for levels I, II, III, IV, and V was 11.7, 10.4, 11.8, 10.4, and 9.2 years, respectively. Thirty-six percent of patients received NHT. The 5-year overall survival was 90%, 87%, 88%, 89%, and 88% for dose levels I-V, respectively. The 5-year clinical disease-free survival (excluding protocol prostate-specific antigen definition) for levels I-V is 84%, 78%, 81%, 82%, and 82%, respectively. By ASTRO definition, the 5-year disease-free survivals were 57%, 59%, 52%, 64% and 75% (low risk); 46%, 52%, 54%, 56%, and 63% (intermediate risk); and 50%, 34%, 46%, 34%, and 61% (high risk) for levels I-V, respectively. By the Phoenix definition, the 5-year disease-free survivals were 68%, 73%, 67%, 84%, and 80% (low risk); 70%, 62%, 70%, 74%, and 69% (intermediate risk); and 42%, 62%, 68%, 54%, and 67% (high risk) for levels I-V, respectively. Conclusion: Dose-escalated 3D-CRT yields favorable outcomes for localized prostate cancer. This multi-institutional experience allows comparison to other experiences with modern radiation therapy.

  3. Comparison of radiotherapy dosimetry for 3D-CRT, IMRT, and SBRT based on electron density calibration

    NASA Astrophysics Data System (ADS)

    Kartutik, K.; Wibowo, W. E.; Pawiro, S. A.

    2016-03-01

    Accurate calculation of dose distribution affected by inhomogeneity tissue is required in radiotherapy planning. This study was performed to determine the ratio between radiotherapy planning using 3D-CRT, IMRT, and SBRT based on a calibrated curve of CT-number in the lung for different target's shape in 3D-CRT, IMRT, and spinal cord for SBRT. Calibration curves of CT-number were generated under measurement basis and introduced into TPS, then planning was performed for 3D-CRT, IMRT, and SBRT with 7, and 15 radiation fields. Afterwards, planning evaluation was performed by comparing the DVH curve, HI, and CI. 3D-CRT and IMRT produced the lowest HI at calibration curve of CIRS 002LFC with the value 0.24 and 10. Whereas SBRT produced the lowest HI on a linear calibration curve with a value of 0.361. The highest CI in IMRT and SBRT technique achieved using a linear calibration curve was 0.97 and 1.77 respectively. For 3D-CRT, the highest CI was obtained by using calibration curve of CIRS 062M with the value of 0.45. From the results of CI and HI, it is concluded that the calibration curve of CT-number does not significantly differ with Schneider's calibrated curve, and inverse planning gives a better result than forward planning.

  4. Respiratory gating for proton beam scanning versus photon 3D-CRT for breast cancer radiotherapy.

    PubMed

    Flejmer, Anna M; Edvardsson, Anneli; Dohlmar, Frida; Josefsson, Dan; Nilsson, Mats; Witt Nyström, Petra; Dasu, Alexandru

    2016-05-01

    Background Respiratory gating and proton therapy have both been proposed to reduce the cardiopulmonary burden in breast cancer radiotherapy. This study aims to investigate the additional benefit of proton radiotherapy for breast cancer with and without respiratory gating. Material and methods Twenty left-sided patients were planned on computed tomography (CT)-datasets acquired during enhanced inspiration gating (EIG) and free-breathing (FB), using photon three-dimensional conformal radiation therapy (3D-CRT) and scanned proton beams. Ten patients received treatment to the whole breast only (WBO) and 10 were treated to the breast and the regional lymph nodes (BRN). Dosimetric parameters characterizing the coverage of target volumes and the cardiopulmonary burden were compared using a paired, two-tailed Student's t-test. Results Protons ensured comparable or better target coverage than photons in all patients during both EIG and FB. The heterogeneity index decreased from 12% with photons to about 5% with protons. The mean dose to the ipsilateral lung was reduced in BRN patients from 12 Gy to 7 Gy  (RBE) in EIG and from 14 Gy to 6-7 Gy (RBE) in FB, while for WBO patients all values were about 5-6 Gy (RBE). The mean dose to heart decreased by a factor of four in WBO patients [from 1.1 Gy to 0.3 Gy (RBE) in EIG and from 2.1 Gy to 0.5 Gy (RBE) in FB] and 10 in BRN patients [from 2.1 Gy to 0.2 Gy (RBE) in EIG and from 3.4 Gy to 0.3 Gy (RBE) in FB]. Similarly, the mean and the near maximum dose to the left anterior descending artery (LAD) were significantly lower (p < 0.05) with protons in comparison with photons. Conclusion Proton spot scanning has a high potential to reduce the irradiation of organs at risk and other normal tissues for most patients, beyond what could be achieved with EIG and photon therapy. The largest dose sparing has been seen for BRN patients, both in terms of cardiopulmonary burden and integral dose.

  5. A Comparison of Helical Intensity-Modulated Radiotherapy, Intensity-Modulated Radiotherapy, and 3D-Conformal Radiation Therapy for Pancreatic Cancer

    SciTech Connect

    Poppe, Matthew M.; Narra, Venkat; Yue, Ning J.; Zhou Jinghao; Nelson, Carl; Jabbour, Salma K.

    2011-01-01

    We assessed dosimetric differences in pancreatic cancer radiotherapy via helical intensity-modulated radiotherapy (HIMRT), linac-based IMRT, and 3D-conformal radiation therapy (3D-CRT) with regard to successful plan acceptance and dose to critical organs. Dosimetric analysis was performed in 16 pancreatic cases that were planned to 54 Gy; both post-pancreaticoduodenectomy (n = 8) and unresected (n = 8) cases were compared. Without volume modification, plans met constraints 75% of the time with HIMRT and IMRT and 13% with 3D-CRT. There was no statistically significantly improvement with HIMRT over conventional IMRT in reducing liver V35, stomach V45, or bowel V45. HIMRT offers improved planning target volume (PTV) dose homogeneity compared with IMRT, averaging a lower maximum dose and higher volume receiving the prescription dose (D100). HIMRT showed an increased mean dose over IMRT to bowel and liver. Both HIMRT and IMRT offer a statistically significant improvement over 3D-CRT in lowering dose to liver, stomach, and bowel. The results were similar for both unresected and resected patients. In pancreatic cancer, HIMRT offers improved dose homogeneity over conventional IMRT and several significant benefits to 3D-CRT. Factors to consider before incorporating IMRT into pancreatic cancer therapy are respiratory motion, dose inhomogeneity, and mean dose.

  6. In vivo surface dose measurement using GafChromic film dosimetry in breast cancer radiotherapy: comparison of 7-field IMRT, tangential IMRT and tangential 3D-CRT

    PubMed Central

    2014-01-01

    Purpose The purpose of this study was to compare the surface dose of 7-field IMRT (7 F-IMRT), tangential beam IMRT (TB-IMRT), and tangential beam 3D-CRT (3D-CRT) of breast cancer patients receiving adjuvant radiotherapy by means of in vivo GafChromic film dosimetry. Material and methods Breast cancer patients receiving adjuvant radiotherapy of the whole breast or the chest wall were eligible for the study. Study patients were treated with a treatment plan using two different radiotherapy techniques (first patient series, 3D-CRT followed by TB-IMRT; second patient series, TB-IMRT followed by 7 F-IMRT). The surface dose was evaluated on three consecutive treatment fractions per radiotherapy technique using in vivo GafChromic film dosimetry. The paired t-test was used to assess the difference of in vivo GafChromic film readings or calculated plan parameters of the compared pairs of radiation techniques for statistical significance. Results Forty-five unselected breast cancer patients were analysed in this study. 7 F-IMRT significantly reduced the surface dose compared to TB-IMRT. Differences were greatest in the central and lateral breast or chest wall region and amounted to a dose reduction of -11.8% to -18.8%. No significant difference of the surface dose was observed between TB-IMRT and 3D-CRT. A corresponding observation was obtained for the calculated skin dose derived from dose-volume histograms. Conclusions In adjuvant breast cancer radiotherapy, 7 F-IMRT offers a significantly reduced surface dose compared to TB-IMRT or 3D-CRT. PMID:25022449

  7. Hypofractionated breast cancer radiotherapy. Helical tomotherapy in supine position or classic 3D-conformal radiotherapy in prone position: which is better?

    PubMed

    Cammarota, Fabrizio; Giugliano, Francesca Maria; Iadanza, Luciano; Cutillo, Luisa; Muto, Matteo; Toledo, Diego; Ravo, Vincenzo; Falivene, Sara; Muto, Paolo

    2014-03-01

    We propose a comparative dosimetric study of whole-breast hypofractionated radiation therapy using helical tomotherapy (HT) in supine position and 3-D conformal radiotherapy (3D-CRT) in prone position. Twelve patients undergoing breast-conserving therapy were retrospectively selected from October to December 2012. Specific dose-volume parameters were selected for the study. The target coverage was adequate in all patients for both techniques. Significant differences in lung dose distribution were observed: maximum dose (mean value over the 12 plans) was 23.41 Gy in HT plans and 6.65 Gy in 3D-CRT; V20 (i.e. the lung volume receiving 20 Gy) was 0.31% in HT plans and 0.0% in 3D-CRT plans. The mean dose to the heart was 5.57 Gy and 0.93 Gy, respectively. The differences between the two techniques were significant (p<0.05) only for some parameters. We noted better results in the prone position, but with HT, dose constraints were mentioned for the whole set of considered organs.

  8. Single-arc volumetric-modulated arc therapy (sVMAT) as adjuvant treatment for gastric cancer: Dosimetric comparisons with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)

    SciTech Connect

    Wang, Xin; Li, Guangjun; Zhang, Yingjie; Bai, Sen; Xu, Feng; Wei, Yuquan; Gong, Youling

    2013-01-01

    To compare the dosimetric differences between the single-arc volumetric-modulated arc therapy (sVMAT), 3-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) techniques in treatment planning for gastric cancer as adjuvant radiotherapy. Twelve patients were retrospectively analyzed. In each patient's case, the parameters were compared based on the dose-volume histogram (DVH) of the sVMAT, 3D-CRT, and IMRT plans, respectively. Three techniques showed similar target dose coverage. The maximum and mean doses of the target were significantly higher in the sVMAT plans than that in 3D-CRT plans and in the 3D-CRT/IMRT plans, respectively, but these differences were clinically acceptable. The IMRT and sVMAT plans successfully achieved better target dose conformity, reduced the V{sub 20/30}, and mean dose of the left kidney, as well as the V{sub 20/30} of the liver, compared with the 3D-CRT plans. And the sVMAT technique reduced the V{sub 20} of the liver much significantly. Although the maximum dose of the spinal cord were much higher in the IMRT and sVMAT plans, respectively (mean 36.4 vs 39.5 and 40.6 Gy), these data were still under the constraints. Not much difference was found in the analysis of the parameters of the right kidney, intestine, and heart. The IMRT and sVMAT plans achieved similar dose distribution to the target, but superior to the 3D-CRT plans, in adjuvant radiotherapy for gastric cancer. The sVMAT technique improved the dose sparings of the left kidney and liver, compared with the 3D-CRT technique, but showed few dosimetric advantages over the IMRT technique. Studies are warranted to evaluate the clinical benefits of the VMAT treatment for patients with gastric cancer after surgery in the future.

  9. Skin-sparing Helical Tomotherapy vs 3D-conformal Radiotherapy for Adjuvant Breast Radiotherapy: In Vivo Skin Dosimetry Study

    SciTech Connect

    Capelle, Lisa; Warkentin, Heather; MacKenzie, Marc; Joseph, Kurian; Gabos, Zsolt; Pervez, Nadeem; Tankel, Keith; Chafe, Susan; Amanie, John; Ghosh, Sunita; Parliament, Matthew; Abdulkarim, Bassam

    2012-08-01

    Purpose: We investigated whether treatment-planning system (TPS)-calculated dose accurately reflects skin dose received for patients receiving adjuvant breast radiotherapy (RT) with standard three-dimensional conformal RT (3D-CRT) or skin-sparing helical tomotherapy (HT). Methods and Materials: Fifty patients enrolled in a randomized controlled trial investigating acute skin toxicity from adjuvant breast RT with 3D-CRT compared to skin-sparing HT, where a 5-mm strip of ipsilateral breast skin was spared. Thermoluminescent dosimetry or optically stimulated luminescence measurements were made in multiple locations and were compared to TPS-calculated doses. Skin dosimetric parameters and acute skin toxicity were recorded in these patients. Results: With HT there was a significant correlation between calculated and measured dose in the medial and lateral ipsilateral breast (r = 0.67, P<.001; r = 0.44, P=.03, respectively) and the medial and central contralateral breast (r = 0.73, P<.001; r = 0.88, P<.001, respectively). With 3D-CRT there was a significant correlation in the medial and lateral ipsilateral breast (r = 0.45, P=.03; r = 0.68, P<.001, respectively); the medial and central contralateral breast (r = 0.62, P=.001; r = 0.86, P<.001, respectively); and the mid neck (r = 0.42, P=.04, respectively). On average, HT-calculated dose overestimated the measured dose by 14%; 3D-CRT underestimated the dose by 0.4%. There was a borderline association between highest measured skin dose and moist desquamation (P=.05). Skin-sparing HT had greater skin homogeneity (homogeneity index of 1.39 vs 1.65, respectively; P=.005) than 3D-CRT plans. HT plans had a lower skin{sub V50} (1.4% vs 5.9%, respectively; P=.001) but higher skin{sub V40} and skin{sub V30} (71.7% vs 64.0%, P=.02; and 99.0% vs 93.8%, P=.001, respectively) than 3D-CRT plans. Conclusion: The 3D-CRT TPS more accurately reflected skin dose than the HT TPS, which tended to overestimate dose received by 14% in patients

  10. Effect of Radiotherapy Techniques (IMRT vs. 3D-CRT) on Outcome in Patients With Intermediate-Risk Rhabdomyosarcoma Enrolled in COG D9803-A Report From the Children's Oncology Group

    SciTech Connect

    Lin Chi; Donaldson, Sarah S.; Meza, Jane L.; Anderson, James R.; Lyden, Elizabeth R.; Brown, Christopher K.; Morano, Karen; Laurie, Fran; Arndt, Carola A.; Enke, Charles A.; Breneman, John C.

    2012-04-01

    Purpose: To compare the dosimetric parameters of intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) in patients with intermediate-risk rhabdomyosarcoma and to analyze their effect on locoregional control and failure-free survival (FFS). Methods and Materials: The study population consisted of 375 patients enrolled in the Children's Oncology Group protocol D9803 study, receiving IMRT or 3D-CRT. Dosimetric data were collected from 179 patients with an available composite plan. The chi-square test or Fisher's exact test was used to compare the patient characteristics and radiotherapy parameters between the two groups. The interval-to-event outcomes were estimated using the Kaplan-Meier method and compared using log-rank tests. Cox proportional hazards regression analysis was used to examine the effect of the treatment technique on FFS after adjusting for primary site and risk group. Results: The median follow-up time was 5.7 and 4.2 years for patients receiving 3D-CRT and IMRT, respectively. No differences in the 5-year failure of locoregional control (18% vs. 15%) or FFS (72% vs. 76%) rates were noted between the two groups. Multivariate analysis revealed no association between the two techniques and FFS. Patients with primary tumors in parameningeal sites were more likely to receive IMRT than 3D-CRT. IMRT became more common during the later years of the study. Patients receiving IMRT were more likely to receive >50 Gy, photon energy of {<=}6 MV, and >5 radiation fields than those who received 3D-CRT. The coverage of the IMRT planning target volume by the prescription dose was improved compared with the coverage using 3D-CRT with similar target dose heterogeneity. Conclusions: IMRT improved the target dose coverage compared with 3D-CRT, although an improvement in locoregional control or FFS could not be demonstrated in this population. Future studies comparing the integral dose to nontarget tissue and late radiation toxicity

  11. Survival and Quality of Life After Stereotactic or 3D-Conformal Radiotherapy for Inoperable Early-Stage Lung Cancer

    SciTech Connect

    Widder, Joachim; Postmus, Douwe; Ubbels, Jan F.; Wiegman, Erwin M.; Langendijk, Johannes A.

    2011-11-15

    Purpose: To investigate survival and local recurrence after stereotactic ablative radiotherapy (SABR) or three-dimensional conformal radiotherapy (3D-CRT) administered for early-stage primary lung cancer and to investigate longitudinal changes of health-related quality of life (HRQOL) parameters after either treatment. Methods and Materials: Two prospective cohorts of inoperable patients with T1-2N0M0 primary lung tumors were analyzed. Patients received 70 Gy in 35 fractions with 3D-CRT or 60 Gy in three to eight fractions with SABR. Global quality of life (GQOL), physical functioning (PF), and patient-rated dyspnea were assessed using the respective dimensions of European Organization for Research and Treatment of Cancer Core Questionnaire-C30 and LC13. HRQOL was analyzed using multivariate linear mixed-effects modeling, survival and local control (LC) using the Kaplan-Meier method, Cox proportional hazards analysis, and Fine and Gray multivariate competing risk analysis as appropriate. Results: Overall survival (OS) was better after SABR compared with 3D-CRT with a HR of 2.6 (95% confidence interval [CI]: 1.5-4.8; p < 0.01). 3D-CRT conferred a subhazard ratio for LC of 5.0 (95% CI: 1.7-14.7; p < 0.01) compared with SABR. GQOL and PF were stable after SABR (p = 0.21 and p = 0.62, respectively). Dyspnea increased after SABR by 3.2 out of 100 points (95% CI: 1.0-5.3; p < 0.01), which is clinically insignificant. At 1 year, PF decreased by an excess of 8.7 out of 100 points (95% CI: 2.8-14.7; p < 0.01) after 3D-CRT compared with SABR. Conclusion: In this nonrandomized comparison of two prospective cohorts of medically inoperable patients with Stage I lung cancer, OS and LC were better after SABR. GQOL, PF, and patient-rated dyspnea were stable after SABR, whereas PF decreased after 3D-CRT approaching clinical significance already at 1 year.

  12. [Risk of postirradiation induction of cancer of the modern methods of radiotherapy (3D CRT and IMRT) head and neck cancer].

    PubMed

    Milecki, Piotr; Szyfter, Krzysztof; Skowronek, Janusz

    2004-01-01

    Ionizing radiation is a known "universal carcinogen" for a wide variety of tumors in man. Human populations are exposed to radiation coming from natural and industrial environment, and from medical sources. However, these are radiotherapy patients who receive the highest doses. Radiation both mutates and sterilizes cells (lethal effect). The risk of cancer induction from cells that have received very high doses of radiation (therapeutic dose about 2 Gy) is lower then from the cells with low doses, since the majority of them will have been sterilized. The epidemiological studies based on the population of atomic bomb survivors have indicated that the most acceptable model of carcinogenesis is the linear non-threshold model. The evaluation of clinical risk related to a wide range of radiation doses, which range from 0.01 Gy to 2 Gy, is connected with many methodological problems such as: differences in treatment factors (dose range, irradiated volume, anatomical site), unknown epidemiological data (smoking abuse, comorbidity), shortening of the follow-up (short lifespan, migration), evaluation of small groups of patients. The most important difficulty is lack of the sufficient knowledge of genetic background which is probably most significant in carcinogenesis process. The introduction into clinical practice of a new sophisticated method of irradiation such as the three-dimensional conformal radiotherapy (3D CRT) or intensity modulated radiotherapy (IMRT) leads to the increase of low irradiation dose for very large volume of normal tissue. Thus, the evaluation of these new methods in the context of carcinogenesis is a very important objective in the future. Today, we can only introduce the most important questions concerned with the risk of carcinogenesis induction which await answers: what is the risk of induction of cancer due to the implementation of these new methods of treatment, and how important is this risk for clinical practice, especially in the case of

  13. Comparison of Three-Dimensional (3D) Conformal Proton Radiotherapy (RT), 3D Conformal Photon RT, and Intensity-Modulated RT for Retroperitoneal and Intra-Abdominal Sarcomas

    SciTech Connect

    Swanson, Erika L.; Indelicato, Daniel J.; Louis, Debbie; Flampouri, Stella; Li, Zuofeng; Morris, Christopher G.; Paryani, Nitesh; Slopsema, Roelf

    2012-08-01

    Purpose: To compare three-dimensional conformal proton radiotherapy (3DCPT), intensity-modulated photon radiotherapy (IMRT), and 3D conformal photon radiotherapy (3DCRT) to predict the optimal RT technique for retroperitoneal sarcomas. Methods and Materials: 3DCRT, IMRT, and 3DCPT plans were created for treating eight patients with retroperitoneal or intra-abdominal sarcomas. The clinical target volume (CTV) included the gross tumor plus a 2-cm margin, limited by bone and intact fascial planes. For photon plans, the planning target volume (PTV) included a uniform expansion of 5 mm. For the proton plans, the PTV was nonuniform and beam-specific. The prescription dose was 50.4 Gy/Cobalt gray equivalent CGE. Plans were normalized so that >95% of the CTV received 100% of the dose. Results: The CTV was covered adequately by all techniques. The median conformity index was 0.69 for 3DCPT, 0.75 for IMRT, and 0.51 for 3DCRT. The median inhomogeneity coefficient was 0.062 for 3DCPT, 0.066 for IMRT, and 0.073 for 3DCRT. The bowel median volume receiving 15 Gy (V15) was 16.4% for 3DCPT, 52.2% for IMRT, and 66.1% for 3DCRT. The bowel median V45 was 6.3% for 3DCPT, 4.7% for IMRT, and 15.6% for 3DCRT. The median ipsilateral mean kidney dose was 22.5 CGE for 3DCPT, 34.1 Gy for IMRT, and 37.8 Gy for 3DCRT. The median contralateral mean kidney dose was 0 CGE for 3DCPT, 6.4 Gy for IMRT, and 11 Gy for 3DCRT. The median contralateral kidney V5 was 0% for 3DCPT, 49.9% for IMRT, and 99.7% for 3DCRT. Regardless of technique, the median mean liver dose was <30 Gy, and the median cord V50 was 0%. The median integral dose was 126 J for 3DCPT, 400 J for IMRT, and 432 J for 3DCRT. Conclusions: IMRT and 3DCPT result in plans that are more conformal and homogenous than 3DCRT. Based on Quantitative Analysis of Normal Tissue Effects in Clinic benchmarks, the dosimetric advantage of proton therapy may be less gastrointestinal and genitourinary toxicity.

  14. Prone Hypofractionated Whole-Breast Radiotherapy Without a Boost to the Tumor Bed: Comparable Toxicity of IMRT Versus a 3D Conformal Technique

    SciTech Connect

    Hardee, Matthew E.; Raza, Shahzad; Becker, Stewart J.; Jozsef, Gabor; Lymberis, Stella C.; Hochman, Tsivia; Goldberg, Judith D.; DeWyngaert, Keith J.; Formenti, Silvia C.

    2012-03-01

    Purpose: We report a comparison of the dosimetry and toxicity of three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT) among patients treated in the prone position with the same fractionation and target of the hypofractionation arm of the Canadian/Whelan trial. Methods and Materials: An institutional review board-approved protocol identified a consecutive series of early-stage breast cancer patients treated according to the Canadian hypofractionation regimen but in the prone position. Patients underwent IMRT treatment planning and treatment if the insurance carrier approved reimbursement for IMRT; in case of refusal, a 3D-CRT plan was used. A comparison of the dosimetric and toxicity outcomes during the acute, subacute, and long-term follow-up of the two treatment groups is reported. Results: We included 97 consecutive patients with 100 treatment plans in this study (3 patients with bilateral breast cancer); 40 patients were treated with 3D-CRT and 57 with IMRT. IMRT significantly reduced the maximum dose (Dmax median, 109.96% for 3D-CRT vs. 107.28% for IMRT; p < 0.0001, Wilcoxon test) and improved median dose homogeneity (median, 1.15 for 3D-CRT vs. 1.05 for IMRT; p < 0.0001, Wilcoxon test) when compared with 3D-CRT. Acute toxicity consisted primarily of Grade 1 to 2 dermatitis and occurred in 92% of patients. Grade 2 dermatitis occurred in 13% of patients in the 3D-CRT group and 2% in the IMRT group. IMRT moderately decreased rates of acute pruritus (p = 0.03, chi-square test) and Grade 2 to 3 subacute hyperpigmentation (p = 0.01, Fisher exact test). With a minimum of 6 months' follow-up, the treatment was similarly well tolerated in either group, including among women with large breast volumes. Conclusion: Hypofractionated breast radiotherapy is well tolerated when treating patients in the prone position, even among those with large breast volumes. Breast IMRT significantly improves dosimetry but yields only a modest but

  15. Volumetric Modulation Arc Radiotherapy With Flattening Filter-Free Beams Compared With Static Gantry IMRT and 3D Conformal Radiotherapy for Advanced Esophageal Cancer: A Feasibility Study

    SciTech Connect

    Nicolini, Giorgia; Ghosh-Laskar, Sarbani; Shrivastava, Shyam Kishore; Banerjee, Sushovan; Chaudhary, Suresh; Agarwal, Jai Prakash; Munshi, Anusheel; Clivio, Alessandro; Fogliata, Antonella; Mancosu, Pietro; Vanetti, Eugenio; Cozzi, Luca

    2012-10-01

    Purpose: A feasibility study was performed to evaluate RapidArc (RA), and the potential benefit of flattening filter-free beams, on advanced esophageal cancer against intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT). Methods and Materials: The plans for 3D-CRT and IMRT with three to seven and five to seven fixed beams were compared against double-modulated arcs with avoidance sectors to spare the lungs for 10 patients. All plans were optimized for 6-MV photon beams. The RA plans were studied for conventional and flattening filter-free (FFF) beams. The objectives for the planning target volume were the volume receiving {>=}95% or at most 107% of the prescribed dose of <1% with a dose prescription of 59.4 Gy. For the organs at risk, the lung volume (minus the planning target volume) receiving {>=}5 Gy was <60%, that receiving 20 Gy was <20%-30%, and the mean lung dose was <15.0 Gy. The heart volume receiving 45 Gy was <20%, volume receiving 30 Gy was <50%. The spinal dose received by 1% was <45 Gy. The technical delivery parameters for RA were assessed to compare the normal and FFF beam characteristics. Results: RA and IMRT provided equivalent coverage and homogeneity, slightly superior to 3D-CRT. The conformity index was 1.2 {+-} 0.1 for RA and IMRT and 1.5 {+-} 0.2 for 3D-CRT. The mean lung dose was 12.2 {+-} 4.5 for IMRT, 11.3 {+-} 4.6 for RA, and 10.8 {+-} 4.4 for RA with FFF beams, 18.2 {+-} 8.5 for 3D-CRT. The percentage of volume receiving {>=}20 Gy ranged from 23.6% {+-} 9.1% to 21.1% {+-} 9.7% for IMRT and RA (FFF beams) and 39.2% {+-} 17.0% for 3D-CRT. The heart and spine objectives were met by all techniques. The monitor units for IMRT and RA were 457 {+-} 139, 322 {+-} 20, and 387 {+-} 40, respectively. RA with FFF beams showed, compared with RA with normal beams, a {approx}20% increase in monitor units per Gray, a 90% increase in the average dose rate, and 20% reduction in beam on time (owing to different

  16. Limited Advantages of Intensity-Modulated Radiotherapy Over 3D Conformal Radiation Therapy in the Adjuvant Management of Gastric Cancer

    SciTech Connect

    Alani, Shlomo; Soyfer, Viacheslav; Strauss, Natan; Schifter, Dan; Corn, Benjamin W.

    2009-06-01

    Purpose: Although chemoradiotherapy was considered the standard adjuvant treatment for gastric cancer, a recent Phase III trial (Medical Research Council Adjuvant Gastric Infusional Chemotherapy [MAGIC]) did not include radiotherapy in the randomization scheme because it was considered expendable. Given radiotherapy's potential, efforts needed to be made to optimize its use for treating gastric cancer. We assessed whether intensity-modulated radiotherapy (IMRT) could improve upon our published results in patients treated with three-dimensional (3D) conformal therapy. Methods and Materials: Fourteen patients with adenocarcinoma of the stomach were treated with adjuvant chemoradiotherapy using a noncoplanar four-field arrangement. Subsequently, a nine-field IMRT plan was designed using a CMS Xio IMRT version 4.3.3 module. Two IMRT beam arrangements were evaluated: beam arrangement 1 consisted of gantry angles of 0 deg., 53 deg., 107 deg., 158 deg., 204 deg., 255 deg., and 306 deg.. Beam arrangement 2 consisted of gantry angles of 30 deg., 90 deg., 315 deg., and 345 deg.; a gantry angle of 320 deg./couch, 30 deg.; and a gantry angle of 35{sup o}/couch, 312{sup o}. Both the target volume coverage and the dose deposition in adjacent critical organs were assessed in the plans. Dose-volume histograms were generated for the clinical target volume, kidneys, spine, and liver. Results: Comparison of the clinical target volumes revealed satisfactory coverage by the 95% isodose envelope using either IMRT or 3D conformal therapy. However, IMRT was only marginally better than 3D conformal therapy at protecting the spine and kidneys from radiation. Conclusions: IMRT confers only a marginal benefit in the adjuvant treatment of gastric cancer and should be used only in the small subset of patients with risk factors for kidney disease or those with a preexisting nephropathy.

  17. Intensity-Modulated and 3D-Conformal Radiotherapy for Whole-Ventricular Irradiation as Compared With Conventional Whole-Brain Irradiation in the Management of Localized Central Nervous System Germ Cell Tumors

    SciTech Connect

    Chen, Michael Jenwei; Silva Santos, Adriana da; Sakuraba, Roberto Kenji; Lopes, Cleverson Perceu; Goncalves, Vinicius Demanboro; Weltman, Eduardo; Ferrigno, Robson; Cruz, Jose Carlos

    2010-02-01

    Purpose: To compare the sparing potential of cerebral hemispheres with intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) for whole-ventricular irradiation (WVI) and conventional whole-brain irradiation (WBI) in the management of localized central nervous system germ cell tumors (CNSGCTs). Methods and Materials: Ten cases of patients with localized CNSGCTs and submitted to WVI by use of IMRT with or without a 'boost' to the primary lesion were selected. For comparison purposes, similar treatment plans were produced by use of 3D-CRT (WVI with or without boost) and WBI (opposed lateral fields with or without boost), and cerebral hemisphere sparing was evaluated at dose levels ranging from 2 Gy to 40 Gy. Results: The median prescription dose for WVI was 30.6 Gy (range, 25.2-37.5 Gy), and that for the boost was 16.5 Gy (range, 0-23.4 Gy). Mean irradiated cerebral hemisphere volumes were lower for WVI with IMRT than for 3D-CRT and were lower for WVI with 3D-CRT than for WBI. Intensity-modulated radiotherapy was associated with the lowest irradiated volumes, with reductions of 7.5%, 12.2%, and 9.0% at dose levels of 20, 30, and 40 Gy, respectively, compared with 3D-CRT. Intensity-modulated radiotherapy provided statistically significant reductions of median irradiated volumes at all dose levels (p = 0.002 or less). However, estimated radiation doses to peripheral areas of the body were 1.9 times higher with IMRT than with 3D-CRT. Conclusions: Although IMRT is associated with increased radiation doses to peripheral areas of the body, its use can spare a significant amount of normal central nervous system tissue compared with 3D-CRT or WBI in the setting of CNSGCT treatment.

  18. Survey of Stereotactic Body Radiation Therapy in Japan by the Japan 3-D Conformal External Beam Radiotherapy Group

    SciTech Connect

    Nagata, Yasushi Hiraoka, Masahiro; Mizowaki, Takashi; Narita, Yuichiro; Matsuo, Yukinori; Norihisa, Yoshiki; Onishi, Hiroshi; Shirato, Hiroki

    2009-10-01

    Purpose: To recognize the current status of stereotactic body radiotherapy (SBRT) in Japan, using a nationwide survey conducted by the Japan 3-D Conformal External Beam Radiotherapy Group. Methods and Materials: The questionnaire was sent by mail to 117 institutions. Ninety-four institutions (80%) responded by the end of November 2005. Fifty-three institutions indicated that they have already started SBRT, and 38 institutions had been reimbursed by insurance. Results: A total of 1111 patients with histologically confirmed lung cancer were treated. Among these patients, 637 had T1N0M0 and 272 had T2N0M0 lung cancer. Metastatic lung cancer was found in 702 and histologically unconfirmed lung tumor in 291 patients. Primary liver cancer was found in 207 and metastatic liver cancer in 76 patients. The most frequent schedule used for primary lung cancer was 48Gy in 4 fractions at 22 institutions (52%), followed by 50Gy in 5 fractions at 11 institutions (26%) and 60Gy in 8 fractions at 4 institutions (10%). The tendency was the same for metastatic lung cancer. The average number of personnel involved in SBRT was 1.8 radiation oncologists, including 1.1 certified radiation oncologists, 2.8 technologists, 0.7 nurses, and 0.6 certified quality assurance personnel and 0.3 physicists. The most frequent amount of time for treatment planning was 61-120min, for quality assurance was 50-60min, and for treatment was 30min. There were 14 (0.6% of all cases) reported Grade 5 complications: 11 cases of radiation pneumonitis, 2 cases of hemoptysis, and 1 case of radiation esophagitis. Conclusion: The current status of SBRT in Japan was surveyed.

  19. Toxicity Profile of IMRT Vs. 3D-CRT in Head and Neck Cancer: A Retrospective Study

    PubMed Central

    Tallari, Ramanjis; Malviya, Anupam

    2016-01-01

    Introduction Role of radiotherapy in comprehensive management of head and neck cancer for achieving tumour control and organ preservation is now well established and radiotherapy is routinely used in adjuvant setting after surgery, concurrently with chemotherapy or targeted agents and for palliation. Development of linear accelerator with Multileaf Collimator (MLC) have revolutionized radiation delivery techniques, allowing conformal and Intensity Modulated Radiotherapy (IMRT) to deliver highly conformal sculpted radiation dose to a very complex structure with improved sparing of adjoining critical structures like salivary glands, spinal cord, eyes, brainstem and larynx amounting to better therapeutic gain. Aim This retrospective study was to compare toxicity profile of IMRT with Three Dimensional Conformal Radiotherapy (3D CRT) in head and neck cancer. Materials and Methods Total of 80 patients from January 2013 to July 2015 with proven head and neck cancer who underwent radiotherapy on linac 2300 C/D machine were included in the study, IMRT group and 3D-CRT group comprised of 40 patients each. We have searched patient’s radiotherapy details in record section of our institute and observations were noted down. Patients received 70Gy/35 fractions, Monday to Friday as radical treatment and 60 Gy/30 fractions as adjuvant treatment were included. Results The 3D-CRT group demonstrated significantly more acute toxic effects compared with the IMRT group in our analysis. Acute Grade 3 or greater toxic effects to the skin occurred in 5 of 40 (12.5%), patients in the 3D-CRT group compared with 3 of 40 (7.5%) patients in the IMRT group. Acute Grade 3 or greater toxic effects to the mucous membranes occurred in 23 of 40 (57.5%) patients in the 3D-CRT group and only 16 of 40 (40%) patients in the IMRT group. Statistically significant dysphagia developed in 34 of 40 (85%), patients in 3D-CRT group compared with 23 of 40 (57.5%) patients in IMRT group, while statistically

  20. Interim Cosmetic Results and Toxicity Using 3D Conformal External Beam Radiotherapy to Deliver Accelerated Partial Breast Irradiation in Patients With Early-Stage Breast Cancer Treated With Breast-Conserving Therapy

    SciTech Connect

    Vicini, Frank A. Chen, Peter; Wallace, Michelle; Mitchell, Christina; Hasan, Yasmin; Grills, Inga; Kestin, Larry; Schell, Scott; Goldstein, Neal S.; Kunzman, Jonathan; Gilbert, Sam; Martinez, Alvaro

    2007-11-15

    Purpose: We present our ongoing clinical experience utilizing three-dimensional (3D)-conformal radiation therapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer treated with breast-conserving therapy. Methods and Materials: Ninety-one consecutive patients were treated with APBI using our previously reported 3D-CRT technique. The clinical target volume consisted of the lumpectomy cavity plus a 10- to 15 -mm margin. The prescribed dose was 34 or 38.5 Gy in 10 fractions given over 5 consecutive days. The median follow-up was 24 months. Twelve patients have been followed for {>=}4 years, 20 for {>=}3.5 years, 29 for >3.0 years, 33 for {>=}2.5 years, and 46 for {>=}2.0 years. Results: No local recurrences developed. Cosmetic results were rated as good/excellent in 100% of evaluable patients at {>=} 6 months (n = 47), 93% at 1 year (n = 43), 91% at 2 years (n = 21), and in 90% at {>=}3 years (n = 10). Erythema, hyperpigmentation, breast edema, breast pain, telangiectasias, fibrosis, and fat necrosis were evaluated at 6, 24, and 36 months after treatment. All factors stabilized by 3 years posttreatment with grade I or II rates of 0%, 0%, 0%, 0%, 9%, 18%, and 9%, respectively. Only 2 patients (3%) developed grade III toxicity (breast pain), which resolved with time. Conclusions: Delivery of APBI with 3D-CRT resulted in minimal chronic ({>=}6 months) toxicity to date with good/excellent cosmetic results. Additional follow-up is needed to assess the long-term efficacy of this form of APBI.

  1. Improvement in toxicity in high risk prostate cancer patients treated with image-guided intensity-modulated radiotherapy compared to 3D conformal radiotherapy without daily image guidance

    PubMed Central

    2014-01-01

    Background Image-guided radiotherapy (IGRT) facilitates the delivery of a very precise radiation dose. In this study we compare the toxicity and biochemical progression-free survival between patients treated with daily image-guided intensity-modulated radiotherapy (IG-IMRT) and 3D conformal radiotherapy (3DCRT) without daily image guidance for high risk prostate cancer (PCa). Methods A total of 503 high risk PCa patients treated with radiotherapy (RT) and endocrine treatment between 2000 and 2010 were retrospectively reviewed. 115 patients were treated with 3DCRT, and 388 patients were treated with IG-IMRT. 3DCRT patients were treated to 76 Gy and without daily image guidance and with 1–2 cm PTV margins. IG-IMRT patients were treated to 78 Gy based on daily image guidance of fiducial markers, and the PTV margins were 5–7 mm. Furthermore, the dose-volume constraints to both the rectum and bladder were changed with the introduction of IG-IMRT. Results The 2-year actuarial likelihood of developing grade > = 2 GI toxicity following RT was 57.3% in 3DCRT patients and 5.8% in IG-IMRT patients (p < 0.001). For GU toxicity the numbers were 41.8% and 29.7%, respectively (p = 0.011). On multivariate analysis, 3DCRT was associated with a significantly increased risk of developing grade > = 2 GI toxicity compared to IG-IMRT (p < 0.001, HR = 11.59 [CI: 6.67-20.14]). 3DCRT was also associated with an increased risk of developing GU toxicity compared to IG-IMRT. The 3-year actuarial biochemical progression-free survival probability was 86.0% for 3DCRT and 90.3% for IG-IMRT (p = 0.386). On multivariate analysis there was no difference in biochemical progression-free survival between 3DCRT and IG-IMRT. Conclusion The difference in toxicity can be attributed to the combination of the IMRT technique with reduced dose to organs-at-risk, daily image guidance and margin reduction. PMID:24495815

  2. Recurrence patterns of locally advanced head and neck squamous cell carcinoma after 3D conformal (chemo)-radiotherapy

    PubMed Central

    2011-01-01

    Background To establish recurrence patterns among locally advanced head and neck non-nasopharyngeal squamous cell carcinoma (HNSCC) patients treated with radical (chemo-) radiotherapy and to correlate the sites of loco-regional recurrence with radiotherapy doses and target volumes Method 151 locally advanced HNSCC patients were treated between 2004-2005 using radical three-dimensional conformal radiotherapy. Patients with prior surgery to the primary tumour site were excluded. The sites of locoregional relapses were correlated with radiotherapy plans by the radiologist and a planning dosimetrist. Results Median age was 59 years (range:34-89). 35 patients had stage III disease, 116 patients had stage IV A/B. 36 patients were treated with radiotherapy alone, 42 with induction chemotherapy, 63 with induction and concomitant chemoradiotherapy and 10 concomitant chemoradiotherapy. Median follow-up was 38 months (range 3-62). 3-year cause specific survival was 66.8%. 125 of 151 (82.8%) achieved a complete response to treatment. Amongst these 125 there were 20 local-regional recurrence, comprising 8 local, 5 regional and 7 simultaneous local and regional; synchronous distant metastases occurred in 7 of the 20. 9 patients developed distant metastases in the absence of locoregional failure. For the 14 local recurrences with planning data available, 12 were in-field, 1 was marginal, and 1 was out-of-field. Of the 11 regional failures with planning data available, 7 were in-field, 1 was marginal and 3 were out-of-field recurrences. Conclusion The majority of failures following non-surgical treatment for locally advanced HNSCC were loco-regional, within the radiotherapy target volume. Improving locoregional control remains a high priority. PMID:21609453

  3. IMRT versus 3D-CRT for thyroid cancer

    NASA Astrophysics Data System (ADS)

    Gizynska, Marta K.; Zawadzka, Anna

    2008-01-01

    A 3D-CRT involving a 4-field (5-field, 6-field, etc.) technique (photon and electron beams) and an alternative IMRT 7-field technique with 6 MV photon fields for thyroid cancer were compared. The IMRT allows reduction in the dose to the spinal cord of about 12 Gy and permits better coverage of the target volume with smaller standard deviation (average 4.65% for 3D-CRT as compared with 1.81% for IMRT). The time needed to prepare therapy (TPS, dosimetry, preparing boluses and electron aperture) and the session time are about the same for both techniques.

  4. The use of radiochromic EBT2 film for the quality assurance and dosimetric verification of 3D conformal radiotherapy using Microtek ScanMaker 9800XL flatbed scanner.

    PubMed

    Sim, G S; Wong, J H D; Ng, K H

    2013-07-08

    Radiochromic and radiographic films are widely used for radiation dosimetry due to the advantage of high spatial resolution and two-dimensional dose measurement. Different types of scanners, including various models of flatbed scanners, have been used as part of the dosimetry readout procedure. This paper focuses on the characterization of the EBT2 film response in combination with a Microtek ScanMaker 9800XL scanner and the subsequent use in the dosimetric verification of a 3D conformal radiotherapy treatment. The film reproducibility and scanner uniformity of the Microtek ScanMaker 9800XL was studied. A three-field 3D conformal radiotherapy treatment was planned on an anthropomorphic phantom and EBT2 film measurements were carried out to verify the treatment. The interfilm reproducibility was found to be 0.25%. Over a period of three months, the films darkened by 1%. The scanner reproducibility was ± 2% and a nonuniformity was ±1.9% along the direction perpendicular to the scan direction. EBT2 measurements showed an underdose of 6.2% at high-dose region compared to TPS predicted dose. This may be due to the inability of the treatment planning system to predict the correct dose distribution in the presence of tissue inhomogeneities and the uncertainty of the scanner reproducibility and uniformity. The use of EBT2 film in conjunction with the axial CT image of the anthropomorphic phantom allows the evaluation of the anatomical location of dose discrepancies between the EBT2 measured dose distribution and TPS predicted dose distribution.

  5. Retrospective evaluation of dosimetric quality for prostate carcinomas treated with 3D conformal, intensity modulated and volumetric modulated arc radiotherapy

    SciTech Connect

    Crowe, Scott B; Kairn, Tanya; Middlebrook, Nigel; Hill, Brendan; Christie, David R H; Knight, Richard T; Kenny, John; Langton, Christian M; Trapp, Jamie V

    2013-12-15

    This study examines and compares the dosimetric quality of radiotherapy treatment plans for prostate carcinoma across a cohort of 163 patients treated across five centres: 83 treated with three-dimensional conformal radiotherapy (3DCRT), 33 treated with intensity modulated radiotherapy (IMRT) and 47 treated with volumetric modulated arc therapy (VMAT). Treatment plan quality was evaluated in terms of target dose homogeneity and organs at risk (OAR), through the use of a set of dose metrics. These included the mean, maximum and minimum doses; the homogeneity and conformity indices for the target volumes; and a selection of dose coverage values that were relevant to each OAR. Statistical significance was evaluated using two-tailed Welch's T-tests. The Monte Carlo DICOM ToolKit software was adapted to permit the evaluation of dose metrics from DICOM data exported from a commercial radiotherapy treatment planning system. The 3DCRT treatment plans offered greater planning target volume dose homogeneity than the other two treatment modalities. The IMRT and VMAT plans offered greater dose reduction in the OAR: with increased compliance with recommended OAR dose constraints, compared to conventional 3DCRT treatments. When compared to each other, IMRT and VMAT did not provide significantly different treatment plan quality for like-sized tumour volumes. This study indicates that IMRT and VMAT have provided similar dosimetric quality, which is superior to the dosimetric quality achieved with 3DCRT.

  6. Retrospective evaluation of dosimetric quality for prostate carcinomas treated with 3D conformal, intensity modulated and volumetric modulated arc radiotherapy

    PubMed Central

    Crowe, Scott B; Kairn, Tanya; Middlebrook, Nigel; Hill, Brendan; Christie, David R H; Knight, Richard T; Kenny, John; Langton, Christian M; Trapp, Jamie V

    2013-01-01

    Introduction This study examines and compares the dosimetric quality of radiotherapy treatment plans for prostate carcinoma across a cohort of 163 patients treated across five centres: 83 treated with three-dimensional conformal radiotherapy (3DCRT), 33 treated with intensity modulated radiotherapy (IMRT) and 47 treated with volumetric modulated arc therapy (VMAT). Methods Treatment plan quality was evaluated in terms of target dose homogeneity and organs at risk (OAR), through the use of a set of dose metrics. These included the mean, maximum and minimum doses; the homogeneity and conformity indices for the target volumes; and a selection of dose coverage values that were relevant to each OAR. Statistical significance was evaluated using two-tailed Welch's T-tests. The Monte Carlo DICOM ToolKit software was adapted to permit the evaluation of dose metrics from DICOM data exported from a commercial radiotherapy treatment planning system. Results The 3DCRT treatment plans offered greater planning target volume dose homogeneity than the other two treatment modalities. The IMRT and VMAT plans offered greater dose reduction in the OAR: with increased compliance with recommended OAR dose constraints, compared to conventional 3DCRT treatments. When compared to each other, IMRT and VMAT did not provide significantly different treatment plan quality for like-sized tumour volumes. Conclusions This study indicates that IMRT and VMAT have provided similar dosimetric quality, which is superior to the dosimetric quality achieved with 3DCRT. PMID:26229621

  7. Predictive parameters in hypofractionated whole-breast 3D conformal radiotherapy according to the Ontario Canadian trial

    PubMed Central

    Lazzari, Grazia; Terlizzi, Angela; Della Vittoria Scarpati, Giuseppina; Perri, Francesco; De Chiara, Vincenzo; Turi, Barbara; Silvano, Giovanni

    2017-01-01

    Aim To evaluate the possible role of dosimetric parameters according Normal Tissue Complication Probability (NTCP) model as predictive of late toxicity and cosmesis in hypofractionated whole-breast three-dimensional conformal radiotherapy. Patients and methods A retrospective analysis on 215 consecutive early breast cancer patients treated with breast conserving surgery and adjuvant hypofractionated whole-breast radiotherapy (according the Ontario Canadian trial), with a 6 years median follow-up was conducted. To assess the impact of 10%–20% dose hotspots on different percent values of planning target volume (PTV) of the breast, we retrospectively employed the NTCP model of Lyman. PTV breast (PTVbr), V110 were identified. For statistical analysis the χ2 and paired t-test were used to find a correlation between late skin and subcutaneous toxicity and cosmetic outcome with dosimetrical parameters Multivariate analysis was performed with the aim to assess independently the impact of dosimetric and clinical parameters on late toxicity and cosmesis using Pearson’s covariance. Results Late skin toxicity was recorded in 47/215 (22%); and G3 toxicity occurred in 11 patients (5%). Cosmesis with excellent–good score was found in 172 patients (80%) while fair–poor score was found in 43 patients (20%). In univariate χ2 analysis the V110 >10% of the PTV breast significantly correlated with higher toxicity (P<0.005, OR 9.60 [CI 3.89–23.72]). Cosmesis related to V110 >10% and PTV breast volume over 1,300 cc was significant at multivariate analysis (P<0.005, OR 6.07 [CI 2.36–15.59]). Conclusion To safely use one of the most important whole-breast hypofractionated radiotherapy schedules, we found some predictive paramaters on the basis of NTCP model by Lyman. These parameters may be useful in selection of elegible patients. PMID:28392704

  8. Results and DVH analysis of late rectal bleeding in patients treated with 3D-CRT or IMRT for localized prostate cancer

    PubMed Central

    Someya, Masanori; Hori, Masakazu; Tateoka, Kunihiko; Nakata, Kensei; Takagi, Masaru; Saito, Masato; Hirokawa, Naoki; Hareyama, Masato; Sakata, Koh-ichi

    2015-01-01

    In patients undergoing radiotherapy for localized prostate cancer, dose–volume histograms and clinical variables were examined to search for correlations between radiation treatment planning parameters and late rectal bleeding. We analyzed 129 patients with localized prostate cancer who were managed from 2002 to 2010 at our institution. They were treated with 3D conformal radiation therapy (3D-CRT, 70 Gy/35 fractions, 55 patients) or intensity-modulated radiation therapy (IMRT, 76 Gy/38 fractions, 74 patients). All radiation treatment plans were retrospectively reconstructed, dose–volume histograms of the rectum were generated, and the doses delivered to the rectum were calculated. Time to rectal bleeding ranged from 9–53 months, with a median of 18.7 months. Of the 129 patients, 33 patients had Grade 1 bleeding and were treated with steroid suppositories, while 25 patients with Grade 2 bleeding received argon plasma laser coagulation therapy (APC). Three patients with Grade 3 bleeding required both APC and blood transfusion. The 5-year incidence rate of Grade 2 or 3 rectal bleeding was 21.8% for the 3D-CRT group and 21.6% for the IMRT group. Univariate analysis showed significant differences in the average values from V65 to V10 between Grades 0–1 and Grades 2–3. Multivariate analysis demonstrated that patients with V65 ≥ 17% had a significantly increased risk (P = 0.032) of Grade 2 or 3 rectal bleeding. Of the 28 patients of Grade 2 or 3 rectal bleeding, 17 patients (60.7%) were cured by a single session of APC, while the other 11 patients required two sessions. Thus, none of the patients had any further rectal bleeding after the second APC session. PMID:25212601

  9. Individualized margins in 3D conformal radiotherapy planning for lung cancer: analysis of physiological movements and their dosimetric impacts.

    PubMed

    Germain, François; Beaulieu, Luc; Fortin, André

    2008-01-01

    In conformal radiotherapy planning for lung cancer, respiratory movements are not taken into account when a single computed tomography (CT) scan is performed. This study examines tumor movements to design individualized margins to account for these movements and evaluates their dosimetric impacts on planning volume. Fifteen patients undergoing CT-based planning for radical radiotherapy for localized lung cancer formed the study cohort. A reference plan was constructed based on reference gross, clinical, and planning target volumes (rGTV, rCTV, and rPTV, respectively). The reference plans were compared with individualized plans using individualized margins obtained by using 5 serial CT scans to generate individualized target volumes (iGTV, iCTV, and iPTV). Three-dimensional conformal radiation therapy was used for plan generation using 6- and 23-MV photon beams. Ten plans for each patient were generated and dose-volume histograms (DVHs) were calculated. Comparisons of volumetric and dosimetric parameters were performed using paired Student t-tests. Relative to the rGTV, the total volume occupied by the superimposed GTVs increased progressively with each additional CT scans. With the use of all 5 scans, the average increase in GTV was 52.1%. For the plans with closest dosimetric coverage, target volume was smaller (iPTV/rPTV ratio 0.808) but lung irradiation was only slightly decreased. Reduction in the proportion of lung tissue that received 20 Gy or more outside the PTV (V20) was observed both for 6-MV plans (-0.73%) and 23-MV plans (-0.65%), with p = 0.02 and p = 0.04, respectively. In conformal RT planning for the treatment of lung cancer, the use of serial CT scans to evaluate respiratory motion and to generate individualized margins to account for these motions produced only a limited lung sparing advantage.

  10. Individualized Margins in 3D Conformal Radiotherapy Planning for Lung Cancer: Analysis of Physiological Movements and Their Dosimetric Impacts

    SciTech Connect

    Germain, Francois Beaulieu, Luc; Fortin, Andre

    2008-04-01

    In conformal radiotherapy planning for lung cancer, respiratory movements are not taken into account when a single computed tomography (CT) scan is performed. This study examines tumor movements to design individualized margins to account for these movements and evaluates their dosimetric impacts on planning volume. Fifteen patients undergoing CT-based planning for radical radiotherapy for localized lung cancer formed the study cohort. A reference plan was constructed based on reference gross, clinical, and planning target volumes (rGTV, rCTV, and rPTV, respectively). The reference plans were compared with individualized plans using individualized margins obtained by using 5 serial CT scans to generate individualized target volumes (iGTV, iCTV, and iPTV). Three-dimensional conformal radiation therapy was used for plan generation using 6- and 23-MV photon beams. Ten plans for each patient were generated and dose-volume histograms (DVHs) were calculated. Comparisons of volumetric and dosimetric parameters were performed using paired Student t-tests. Relative to the rGTV, the total volume occupied by the superimposed GTVs increased progressively with each additional CT scans. With the use of all 5 scans, the average increase in GTV was 52.1%. For the plans with closest dosimetric coverage, target volume was smaller (iPTV/rPTV ratio 0.808) but lung irradiation was only slightly decreased. Reduction in the proportion of lung tissue that received 20 Gy or more outside the PTV (V20) was observed both for 6-MV plans (-0.73%) and 23-MV plans (-0.65%), with p = 0.02 and p = 0.04, respectively. In conformal RT planning for the treatment of lung cancer, the use of serial CT scans to evaluate respiratory motion and to generate individualized margins to account for these motions produced only a limited lung sparing advantage.

  11. Dosimetric study of the protection level of the bone marrow in patients with cervical or endometrial cancer for three radiotherapy techniques - 3D CRT, IMRT and VMAT. Study protocol.

    NASA Astrophysics Data System (ADS)

    Jodda, Agata; Urbański, Bartosz; Piotrowski, Tomasz; Malicki, Julian

    2016-03-01

    Background: The paper shows the methodology of an in-phantom study of the protection level of the bone marrow in patients with cervical or endometrial cancer for three radiotherapy techniques: three-dimensional conformal radiotherapy, intensity modulated radiotherapy, and volumetric modulated arc therapy, preceded by the procedures of image guidance. Methods/Design: The dosimetric evaluation of the doses will be performed in an in-house multi-element anthropomorphic phantom of the female pelvic area created by three-dimensional printing technology. The volume and position of the structures will be regulated according to the guidelines from the Bayesian network. The input data for the learning procedure of the model will be obtained from the retrospective analysis of imaging data obtained for 96 patients with endometrial cancer or cervical cancer treated with radiotherapy in our centre in 2008-2013. Three anatomical representations of the phantom simulating three independent clinical cases will be chosen. Five alternative treatment plans (1 × three-dimensional conformal radiotherapy, 2 × intensity modulated radiotherapy and 2 × volumetric modulated arc therapy) will be created for each representation. To simulate image-guided radiotherapy, ten specific recombinations will be designated, for each anatomical representation separately, reflecting possible changes in the volume and position of the phantom components. Discussion: The comparative analysis of planned measurements will identify discrepancies between calculated doses and doses that were measured in the phantom. Finally, differences between the doses cumulated in the hip plates performed by different techniques simulating the gynaecological patients' irradiation of dose delivery will be established. The results of this study will form the basis of the prospective clinical trial that will be designed for the assessment of hematologic toxicity and its correlation with the doses cumulated in the hip plates

  12. SU-E-T-346: Effect of Jaw Position On Dose to Critical Structures in 3-D Conformal Radiotherapy Treatment of Pancreatic Cancer

    SciTech Connect

    Paudel, N; Han, E; Liang, X; Morrill, S; Zhang, X; Hardee, M; Penagaricano, J; Ratanatharathorn, V

    2015-06-15

    Purpose: Three-dimensional conformal therapy remains a valid and widely used modality for pancreatic radiotherapy treatment. It usually meets dose constraints on critical structures. However, careful positioning of collimation jaws can reduce dose to the critical structures. Here we investigate the dosimetric effect of jaw position in MLC-based 3-D conformal treatment planning on critical structures. Methods: We retrospectively selected seven pancreatic cancer patients treated with 3-D conformal radiotherapy. We started with treatment plans (Varian Truebeam LINAC, Eclipse TPS, AAA, 18MV) having both x and y jaws aligned with the farthest extent of the block outline (8mm around PTV). Then we subsequently moved either both x-jaws or all x and y jaws outwards upto 3 cm in 1 cm increments and investigated their effect on average and maximum dose to neighboring critical structures keeping the same coverage to treatment volume. Results: Lateral displacement of both x-jaws by 1cm each increased kidney and spleen mean dose by as much as 1.7% and 1.3% respectively and superior inferior displacement increased liver, right kidney, stomach and spleen dose by as much as 2.1%, 2%, 5.2% and 1.6% respectively. Displacement of all x and y-jaws away by 1cm increased the mean dose to liver, right kidney, left kidney, bowels, cord, stomach and spleen by as much as 4.9%, 5.9%, 2.1%, 2.8%, 7.4%, 10.4% and 4.2% respectively. Percentage increase in mean dose due to 2 and 3cm jaw displacement increased almost linearly with the displaced distance. Changes in maximum dose were much smaller (mostly negligible) than the changes in mean dose. Conclusion: Collimation jaw position affects dose mostly to critical structures adjacent to it. Though treatment plans with MLCs conforming the block margin usually meet dose constraints to critical structures, keeping jaws all the way in, to the edge of the block reduces dose to the critical structures during radiation treatment.

  13. Clinical outcome of protocol based image (MRI) guided adaptive brachytherapy combined with 3D conformal radiotherapy with or without chemotherapy in patients with locally advanced cervical cancer

    PubMed Central

    Pötter, Richard; Georg, Petra; Dimopoulos, Johannes C.A.; Grimm, Magdalena; Berger, Daniel; Nesvacil, Nicole; Georg, Dietmar; Schmid, Maximilian P.; Reinthaller, Alexander; Sturdza, Alina; Kirisits, Christian

    2011-01-01

    Background To analyse the overall clinical outcome and benefits by applying protocol based image guided adaptive brachytherapy combined with 3D conformal external beam radiotherapy (EBRT) ± chemotherapy (ChT). Methods Treatment schedule was EBRT with 45–50.4 Gy ± concomitant cisplatin chemotherapy plus 4 × 7 Gy High Dose Rate (HDR) brachytherapy. Patients were treated in the “protocol period” (2001–2008) with the prospective application of the High Risk CTV concept (D90) and dose volume constraints for organs at risk including biological modelling. Dose volume adaptation was performed with the aim of dose escalation in large tumours (prescribed D90 > 85 Gy), often with inserting additional interstitial needles. Dose volume constraints (D2cc) were 70–75 Gy for rectum and sigmoid and 90 Gy for bladder. Late morbidity was prospectively scored, using LENT/SOMA Score. Disease outcome and treatment related late morbidity were evaluated and compared using actuarial analysis. Findings One hundred and fifty-six consecutive patients (median age 58 years) with cervix cancer FIGO stages IB–IVA were treated with definitive radiotherapy in curative intent. Histology was squamous cell cancer in 134 patients (86%), tumour size was >5 cm in 103 patients (66%), lymph node involvement in 75 patients (48%). Median follow-up was 42 months for all patients. Interstitial techniques were used in addition to intracavitary brachytherapy in 69/156 (44%) patients. Total prescribed mean dose (D90) was 93 ± 13 Gy, D2cc 86 ± 17 Gy for bladder, 65 ± 9 Gy for rectum and 64 ± 9 Gy for sigmoid. Complete remission was achieved in 151/156 patients (97%). Overall local control at 3 years was 95%; 98% for tumours 2–5 cm, and 92% for tumours >5 cm (p = 0.04), 100% for IB, 96% for IIB, 86% for IIIB. Cancer specific survival at 3 years was overall 74%, 83% for tumours 2–5 cm, 70% for tumours >5 cm, 83% for IB, 84% for IIB, 52% for IIIB. Overall

  14. A dose comparison of proton radiotherapy and photon radiotherapy for pediatric brain tumor

    NASA Astrophysics Data System (ADS)

    Kim, S. Y.; Cho, J. H.

    2014-12-01

    The purpose of this study was to investigate the effectiveness of photon radiotherapy and to compare the dose of treatment planning between proton radiotherapy and 3D conformal radiation therapy (3D-CRT) for pediatric brain tumor patients. This study was conducted in five pediatric brain tumor patients who underwent craniospinal irradiation treatment from October 2013 to April 2014 in the hospital. The study compared organs at risk (OARs) by assessing the dose distribution of normal tissue from the proton plan and 3D-CRT. Furthermore, this study assessed the treatment plans by looking at the homogeneity index (HI) and conformity index (CI). As a result, the study revealed OARs due to the small volume proton radiotherapy dose distribution in the normal tissue. Also, by comparing HI and CI between the 3D-CRT and proton radiotherapy plan, the study found that the dose of proton radiotherapy plan was homogenized. When conducting 3D-CRT and proton radiotherapy in a dose-volume histogram comparison, the dose of distribution turned out to be low. Consequently, proton radiotherapy is used for protecting the normal tissue, and is used in tumor tissue as a homogenized dose for effective treatment.

  15. Intensity modulated radiotherapy and 3D conformal radiotherapy for whole breast irradiation: a comparative dosimetric study and introduction of a novel qualitative index for plan evaluation, the normal tissue index

    SciTech Connect

    Yim, Jackie; Suttie, Clare; Bromley, Regina; Morgia, Marita; Lamoury, Gillian

    2015-09-15

    We report on a retrospective dosimetric study, comparing 3D conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (hIMRT). We evaluated plans based on their planning target volume coverage, dose homogeneity, dose to organs at risk (OARs) and exposure of normal tissue to radiation. The Homogeneity Index (HI) was used to assess the dose homogeneity in the target region, and we describe a new index, the normal tissue index (NTI), to assess the dose in the normal tissue inside the tangent treatment portal. Plans were generated for 25 early-stage breast cancer patients, using a hIMRT technique. These were compared with the 3DCRT plans of the treatment previously received by the patients. Plan quality was evaluated using the HI, NTI and dose to OARs. The hIMRT technique was significantly more homogenous than the 3DCRT technique, while maintaining target coverage. The hIMRT technique was also superior at minimising the amount of tissue receiving D{sub 105%} and above (P < 0.0001). The ipsilateral lung and contralateral breast maximum were significantly lower in the hIMRT plans (P < 0.05 and P < 0.005), but the 3DCRT technique achieved a lower mean heart dose in left-sided breast cancer patients (P < 0.05). Hybrid intensity modulated radiotherapy plans achieved improved dose homogeneity compared to the 3DCRT plans and superior outcome with regard to dose to normal tissues. We propose that the addition of both HI and NTI in evaluating the quality of intensity modulated radiotherapy (IMRT) breast plans provides clinically relevant comparators which more accurately reflect the new paradigm of treatment goals and outcomes in the era of breast IMRT.

  16. Radiation-induced second cancers: the impact of 3D-CRT and IMRT

    NASA Technical Reports Server (NTRS)

    Hall, Eric J.; Wuu, Cheng-Shie

    2003-01-01

    Information concerning radiation-induced malignancies comes from the A-bomb survivors and from medically exposed individuals, including second cancers in radiation therapy patients. The A-bomb survivors show an excess incidence of carcinomas in tissues such as the gastrointestinal tract, breast, thyroid, and bladder, which is linear with dose up to about 2.5 Sv. There is great uncertainty concerning the dose-response relationship for radiation-induced carcinogenesis at higher doses. Some animal and human data suggest a decrease at higher doses, usually attributed to cell killing; other data suggest a plateau in dose. Radiotherapy patients also show an excess incidence of carcinomas, often in sites remote from the treatment fields; in addition there is an excess incidence of sarcomas in the heavily irradiated in-field tissues. The transition from conventional radiotherapy to three-dimensional conformal radiation therapy (3D-CRT) involves a reduction in the volume of normal tissues receiving a high dose, with an increase in dose to the target volume that includes the tumor and a limited amount of normal tissue. One might expect a decrease in the number of sarcomas induced and also (less certain) a small decrease in the number of carcinomas. All around, a good thing. By contrast, the move from 3D-CRT to intensity-modulated radiation therapy (IMRT) involves more fields, and the dose-volume histograms show that, as a consequence, a larger volume of normal tissue is exposed to lower doses. In addition, the number of monitor units is increased by a factor of 2 to 3, increasing the total body exposure, due to leakage radiation. Both factors will tend to increase the risk of second cancers. Altogether, IMRT is likely to almost double the incidence of second malignancies compared with conventional radiotherapy from about 1% to 1.75% for patients surviving 10 years. The numbers may be larger for longer survival (or for younger patients), but the ratio should remain the same.

  17. Intensity-modulated radiotherapy reduces gastrointestinal toxicity in locally advanced pancreas cancer

    PubMed Central

    Prasad, Shreya; Cambridge, Lajhem; Huguet, Florence; Chou, Joanne F.; Zhang, Zhigang; Wu, Abraham J.; O'Reilly, Eileen M.; Allen, Peter; Goodman, Karyn A.

    2016-01-01

    Purpose We compared gastrointestinal (GI) and hematologic toxicity in patients with locally advanced pancreas cancer (LAPC) undergoing definitive chemoradiation using intensity modulated radiotherapy (IMRT) or 3D conformal radiotherapy (3D-CRT) planning. Methods and Materials We retrospectively studied 205 patients with LAPC undergoing IMRT (n=134) and 3D-CRT (n=71) between 05/03 and 03/12. Patient, tumor, and treatment characteristics and acute GI/hematology toxicity according to Common Terminology Criteria for Adverse Events v3.0 were recorded. Multivariable logistic regression models were used to test association between acute grade 2+ GI and hematologic toxicity outcomes and predictors. Propensity score analysis for grade 2+ GI toxicity was performed to reduce bias for confounding variables: age, gender, radiation dose, field size, and chemotherapy type. Results Median follow-up time for survivors was 22 months, similar between groups. Median RT dose was significantly higher for IMRT vs. 3D-CRT (5600 cGy vs 5040 cGy, P<.001); concurrent chemotherapy was mainly gemcitabine (56%) or 5-fluorouracil (5-FU, 38%). Grade 2+ GI toxicity occurred in 34% (n=24) of 3D-CRT compared with 16% (n=21) of IMRT patients. Using propensity-score analysis, 3D-CRT had significantly higher grade 2+ GI toxicity (odds ratio, 1.26 [95%CI, 1.08-1.45], P=.001). Grade 2+ hematologic toxicity was similar between IMRT and 3D-CRT groups but was significantly greater in recipients of concurrent gemcitabine over 5-FU (62% vs 29%, P<.0001). Conclusions IMRT is associated with significant lower grade 2+ GI toxicity versus 3D-CRT for patients undergoing definitive chemoradiotherapy for LAPC. Since IMRT is better tolerated at higher doses and may allow further dose escalation, potentially improving local control for this aggressive disease. Further prospective studies of dose-escalated chemoradiation using IMRT are warranted. PMID:26577010

  18. Importance of protocol target definition on the ability to spare normal tissue: An IMRT and 3D-CRT planning comparison for intraorbital tumors

    SciTech Connect

    Hein, Patrick A.; Gladstone, David J.; Bellerive, Marc R.; Hug, Eugen B. . E-mail: Eugen.B.Hug@hitchcock.org

    2005-08-01

    Purpose: We selected five intraorbital tumor sites that are frequently found in clinical practice in children diagnosed with orbital rhabdomyosarcoma and performed three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated photon radiotherapy (IMRT) planning. Results of target coverage and doses to critical structures were compared. The goal of this study was to evaluate and to document realistic expectations as to organ-sparing capabilities of modern radiation therapy planning technologies with a focus on lens-sparing irradiation. Furthermore, we investigated potential added benefits of IMRT compared with 3D-CRT and the influence of protocol volume criteria definitions on the ability to obtain normal tissue dose sparing using the orbit as an example of a complex anatomic site. Methods and Materials: The five intraorbital tumor sites were placed retrobulbar, temporal, nasal, in the upper inner and upper outer quadrant, the latter two more complex in shape. Gross tumor volume (GTV), clinical target volume (CTV), and planning target volume (PTV) were defined in image-fused computed tomography and magnetic resonance data sets. 3D-CRT and IMRT photon plans, using equal beam angles and collimation for direct comparison, were designed to 45 Gy prescription dose according to Intergroup Rhabdomyosarcoma Study Group-D9602 (IRSG-D9602) protocol (Intergroup Rhabdomyosarcoma Study V [IRS-V] protocol) for Stage I, Clinical Group 3 orbital rhabdomyosarcoma. To compare the impact of changed target definitions in IMRT planning, additional IMRT plans were generated using modified volume and dose coverage criteria. The minimum dose constraint (95%) of the PTV was substituted by a required minimum volume coverage (95%) with the prescribed dose. Dose-volume histograms (DVHs) were obtained, including target volumes, lens, optic nerves, optic chiasm, lacrimal gland, bony orbit, pituitary gland, frontal and temporal lobes. Results: Protocol target volume coverage criteria

  19. Whole-pelvic radiotherapy with spot-scanning proton beams for uterine cervical cancer: a planning study

    PubMed Central

    Hashimoto, Shingo; Shibamoto, Yuta; Iwata, Hiromitsu; Ogino, Hiroyuki; Shibata, Hiroki; Toshito, Toshiyuki; Sugie, Chikao; Mizoe, Jun-etsu

    2016-01-01

    The aim of this study was to compare the dosimetric parameters of whole-pelvic radiotherapy (WPRT) for cervical cancer among plans involving 3D conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), or spot-scanning proton therapy (SSPT). The dose distributions of 3D-CRT-, IMRT-, and SSPT-based WPRT plans were compared in 10 patients with cervical cancer. All of the patients were treated with a prescribed dose of 50.4 Gy in 1.8-Gy daily fractions, and all of the plans involved the same planning target volume (PTV) constrictions. A 3D-CRT plan involving a four-field box, an IMRT plan involving seven coplanar fields, and an SSPT plan involving four fields were created. The median PTV D95% did not differ between the 3D-CRT, IMRT and SSPT plans. The median conformity index 95% and homogeneity index of the IMRT and SSPT were better than those of the 3D-CRT. The homogeneity index of the SSPT was better than that of the IMRT. SSPT resulted in lower median V20 values for the bladder wall, small intestine, colon, bilateral femoral heads, skin, and pelvic bone than IMRT. Comparing the Dmean values, SSPT spared the small intestine, colon, bilateral femoral heads, skin and pelvic bone to a greater extent than the other modalities. SSPT can reduce the irradiated volume of the organs at risk compared with 3D-CRT and IMRT, while maintaining excellent PTV coverage. Further investigations of SSPT are warranted to assess its role in the treatment of cervical cancer. PMID:27380800

  20. Involved-Site Image-Guided Intensity Modulated Versus 3D Conformal Radiation Therapy in Early Stage Supradiaphragmatic Hodgkin Lymphoma

    SciTech Connect

    Filippi, Andrea Riccardo; Ciammella, Patrizia; Piva, Cristina; Ragona, Riccardo; Botto, Barbara; Gavarotti, Paolo; Merli, Francesco; Vitolo, Umberto; Iotti, Cinzia; Ricardi, Umberto

    2014-06-01

    Purpose: Image-guided intensity modulated radiation therapy (IG-IMRT) allows for margin reduction and highly conformal dose distribution, with consistent advantages in sparing of normal tissues. The purpose of this retrospective study was to compare involved-site IG-IMRT with involved-site 3D conformal RT (3D-CRT) in the treatment of early stage Hodgkin lymphoma (HL) involving the mediastinum, with efficacy and toxicity as primary clinical endpoints. Methods and Materials: We analyzed 90 stage IIA HL patients treated with either involved-site 3D-CRT or IG-IMRT between 2005 and 2012 in 2 different institutions. Inclusion criteria were favorable or unfavorable disease (according to European Organization for Research and Treatment of Cancer criteria), complete response after 3 to 4 cycles of an adriamycin- bleomycin-vinblastine-dacarbazine (ABVD) regimen plus 30 Gy as total radiation dose. Exclusion criteria were chemotherapy other than ABVD, partial response after ABVD, total radiation dose other than 30 Gy. Clinical endpoints were relapse-free survival (RFS) and acute toxicity. Results: Forty-nine patients were treated with 3D-CRT (54.4%) and 41 with IG-IMRT (45.6%). Median follow-up time was 54.2 months for 3D-CRT and 24.1 months for IG-IMRT. No differences in RFS were observed between the 2 groups, with 1 relapse each. Three-year RFS was 98.7% for 3D-CRT and 100% for IG-IMRT. Grade 2 toxicity events, mainly mucositis, were recorded in 32.7% of 3D-CRT patients (16 of 49) and in 9.8% of IG-IMRT patients (4 of 41). IG-IMRT was significantly associated with a lower incidence of grade 2 acute toxicity (P=.043). Conclusions: RFS rates at 3 years were extremely high in both groups, albeit the median follow-up time is different. Acute tolerance profiles were better for IG-IMRT than for 3D-CRT. Our preliminary results support the clinical safety and efficacy of advanced RT planning and delivery techniques in patients affected with early stage HL, achieving complete

  1. Quantification of Radiation Biomarkers in Leukocytes of Breast Cancer Patients Treated with Different Modalities of 3D-CRT or IMRT.

    PubMed

    Zahnreich, Sebastian; Ebersberger, Anne; Karle, Heiko; Kaina, Bernd; Schmidberger, Heinz

    2016-11-01

    The goal of this study was to determine whether the quantification of radiation biomarkers in peripheral leukocytes of 111 breast cancer patients after adjuvant treatment with different modalities of three-dimensional conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) revealed any difference in the patients' radiation burden by out-of-field doses and an associated risk of second malignancies. Whole-breast radiation therapy was performed by 3D-CRT using either a hard wedge (n = 32) or a virtual wedge (n = 49) at dose rates of 3 and 6 Gy per min each. Patients receiving additional radiotherapy to lymph nodes were treated by 3D-CRT (n = 21) or IMRT (n = 9). DNA damage was measured as γ-H2AX foci (n = 111) and as unstable chromosomal aberrations (n = 15) in leukocytes drawn 30 min and 24 h after the first radiation fraction, respectively. The individual basal yield and radiation sensitivity ex vivo were assessed in leukocytes obtained before the first treatment. After radiation therapy, the average rate of γ-H2AX foci and chromosomal aberrations per leukocyte were dependent on multiple parameters of irradiation: the treatment volume, the administered equivalent whole-body dose, the number of monitor units and the beam-on time. Different modalities of radiation therapy caused significant variations in the levels of both radiation biomarkers irrespective of the treatment volume and administered dose, and in particular, a twofold higher rate after IMRT compared to 3D-CRT. Any deviation in biomarker response between radiation therapy techniques was directed by a linear dependence on the absolute beam-on time. However, the dispersion of γ-H2AX foci in peripheral leukocytes after radiation therapy correlated very well with the relative distribution of dose in the whole-body volume for each radiation therapy technique. In conclusion, the induction of radiation biomarkers in leukocytes of breast cancer patients by different radiotherapy

  2. Out-of-field doses from pediatric craniospinal irradiations using 3D-CRT, IMRT, helical tomotherapy and electron-based therapy.

    PubMed

    De Saint-Hubert, Marijke; Verellen, Dirk; Poels, Kenneth; Crijns, Wouter; Magliona, Federica; Depuydt, Tom; Vanhavere, Filip; Struelens, Lara

    2017-04-11

    Medulloblastoma treatment involves irradiation of the entire central nervous system, i.e craniospinal irradiation (CSI). This is associated with significant exposure of large volumes of healthy tissue with a growing concern regarding treatment associated side effects. The current study compares out-of-field organ doses in children receiving CSI with three-dimensional-conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT) and an electron-based technique, including as well radiation doses resulting from imaging performed during treatment. An extensive phantom study is performed, using an anthropomorphic phantom corresponding to a 5-year old child, in which organ absorbed doses are measured using thermoluminescent detectors (TLDs). Additionally the study evaluates and explores tools for calculating out-of-field patient doses using the treatment planning system (TPS) and analytical models. In our study, 3D-CRT resulted in very high doses to a limited number of organs while it was able to spare organs such as the lungs and breast when compared to IMRT and HT. Both IMRT and HT spread the dose over more organs and were able to spare heart, thyroid, bladder, uterus and testes when compared to 3D-CRT. The electron-based technique considerably decreased the out-of-field doses in deep seated organs but cannot avoid nearby out-of-field organs such as lungs, ribs, adrenals, kidneys and uterus. Daily imaging dose is small compared to the treatment dose burden. TPS error for out-of-field doses was most pronounced for organs further away from the target nevertheless no systematic underestimation was observed for any of the studied TPS systems. Finally analytical modeling was most optimal for 3D-CRT although the number of organs that can be modeled was limited. To conclude none of the techniques studied was able to spare doses in all organs. Nevertheless the electron-based technique showed most promising for out-of-field organ dose

  3. The Effect of Flattening Filter Free on Three-dimensional Conformal Radiation Therapy (3D-CRT), Intensity-Modulated Radiation Therapy (IMRT), and Volumetric Modulated Arc Therapy (VMAT) Plans for Metastatic Brain Tumors from Non-small Cell Lung Cancer.

    PubMed

    Shi, Li-Wan; Lai, You-Qun; Lin, Qin; Ha, Hui-Ming; Fu, Li-Rong

    2015-07-01

    Flattening filter free (FFF) may affect outcome measures of radiotherapy. The objective of this study is to compare the dosimetric parameters in three types of radiotherapy plans, three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT), with or without the flattening filter (FF), developed for the treatment of metastatic brain tumors from non-small cell lung cancer (NSCLC). From July 2013 to October 2013, 3D-CRT, IMRT, and VMAT treatment plans were designed using 6 MV and 10 MV, with and without FF, for 10 patients with brain metastasis from NSCLC. The evaluation of the treatment plans included homogeneity index (HI), conformity index (CI), monitor units (MU), mean dose (Dmean), treatment time, and the influence of FFF on volumes. There was no difference in CI or HI between FFF and FF models with 3D-CRT, IMRT, and VMAT plans. At 6 MV, a lower Dmean was seen in the FFF model of 3D-CRT and in the VMAT plan at 10 MV. In the IMRT 6 MV, IMRT 10 MV, and VMAT 10 MV plans, higher MUs were seen in the FFF models. FFF treatments are similar in quality to FF plans, generally lead to more monitor units, and are associated with shorter treatment times. FFF plans ranked by the order of superiority in terms of a time advantage are VMAT, 3D-CRT, and IMRT.

  4. Evolution of radiation techniques in the treatment of mediastinal lymphoma: from 3D conformal radiotherapy (3DCRT) to intensity-modulated RT (IMRT) using helical tomotherapy (HT): a single-centre experience and review of the literature

    PubMed Central

    Besson, Nadia; Pernin, Victor; Zefkili, Sofia

    2016-01-01

    Objective: To evaluate radiation techniques and their toxicity in the treatment of Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL) with mediastinal disease over a 10-year period. Methods: Between 2003 and 2015, 173 patients with Stage I–III nodal lymphoma were treated in our institution: some of these patients were irradiated for HL or NHL with mediastinal disease. Some of the patients were treated by three-dimensional conformal radiotherapy (3DCRT), others by intensity-modulated radiotherapy (IMRT). Results: We studied 26 males and 43 females with a median age of 26 years. The median follow-up was 43 months. 49 patients were treated by 3DCRT and 20 patients by IMRT. The median dose received by patients treated for NHL was 40 Gy (range: 36–44 Gy), and the median dose received by patients with HL was 30 Gy (range: 30–36 Gy). Between 2003 and 2006, 16 patients were treated by 3DCRT vs 0 patients by IMRT. Between 2007 and 2009, 16 patients received 3DCRT and one patient received IMRT. Between 2010 and 2015, 19 patients received IMRT, and no patients received 3DCRT. 11 of the 20 (55%) patients treated by IMRT and 35 of the 49 (71.4%) patients treated by 3DCRT experienced acute toxicity. Among the patients treated by 3DCRT, one patient experienced Grade 1 radiation pneumonitis and two patients experienced Grade 1 acute mucositis. No late toxicity was observed in patients treated by IMRT. Conclusion: Improvement of radiation techniques for HL and NHL appears to have improved acute and late clinical safety. Longer follow-up is necessary to evaluate very late toxicity. Advances in knowledge: Improvement of radiation techniques for HL and NHL appears to improve the tolerance. PMID:26744079

  5. Initial Efficacy Results of RTOG 0319: Three-Dimensional Conformal Radiation Therapy (3D-CRT) Confined to the Region of the Lumpectomy Cavity for Stage I/ II Breast Carcinoma

    SciTech Connect

    Vicini, Frank; Winter, Kathryn; Wong, John

    2010-07-15

    Purpose: This prospective study (Radiation Therapy Oncology Group 0319) examines the use of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI). Initial data on efficacy and toxicity are presented. Methods and Materials: Patients with Stage I or II breast cancer with lesions {<=}3 cm, negative margins and with {<=}3 positive nodes were eligible. The 3D-CRT was 38.5 Gy in 3.85 Gy/fraction delivered 2x/day. Ipsilateral breast, ipsilateral nodal, contralateral breast, and distant failure (IBF, INF, CBF, DF) were estimated using the cumulative incidence method. Mastectomy-free, disease-free, and overall survival (MFS, DFS, OS) were recorded. The National Cancer Institute Common Terminology Criteria for Adverse Events, version 3, was used to grade acute and late toxicity. Results: Fifty-eight patients were entered and 52 patients are eligible and evaluable for efficacy. The median age of patients was 61 years with the following characteristics: 46% tumor size <1 cm; 87% invasive ductal histology; 94% American Joint Committee on Cancer Stage I; 65% postmenopausal; 83% no chemotherapy; and 71% with no hormone therapy. Median follow-up is 4.5 years (1.7-4.8). Four-year estimates (95% CI) of efficacy are: IBF 6% (0-12%) [4% within field (0-9%)]; INF 2% (0-6%); CBF 0%; DF 8% (0-15%); MFS 90% (78-96%); DFS 84% (71-92%); and OS 96% (85-99%). Only two (4%) Grade 3 toxicities were observed. Conclusions: Initial efficacy and toxicity using 3D-CRT to deliver APBI appears comparable to other experiences with similar follow-up. However, additional patients, further follow-up, and mature Phase III data are needed to evaluate the extent of application, limitations, and value of this particular form of APBI.

  6. Radiation-induced second primary cancer risks from modern external beam radiotherapy for early prostate cancer: impact of stereotactic ablative radiotherapy (SABR), volumetric modulated arc therapy (VMAT) and flattening filter free (FFF) radiotherapy

    NASA Astrophysics Data System (ADS)

    Murray, Louise J.; Thompson, Christopher M.; Lilley, John; Cosgrove, Vivian; Franks, Kevin; Sebag-Montefiore, David; Henry, Ann M.

    2015-02-01

    Risks of radiation-induced second primary cancer following prostate radiotherapy using 3D-conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), flattening filter free (FFF) and stereotactic ablative radiotherapy (SABR) were evaluated. Prostate plans were created using 10 MV 3D-CRT (78 Gy in 39 fractions) and 6 MV 5-field IMRT (78 Gy in 39 fractions), VMAT (78 Gy in 39 fractions, with standard flattened and energy-matched FFF beams) and SABR (42.7 Gy in 7 fractions with standard flattened and energy-matched FFF beams). Dose-volume histograms from pelvic planning CT scans of three prostate patients, each planned using all 6 techniques, were used to calculate organ equivalent doses (OED) and excess absolute risks (EAR) of second rectal and bladder cancers, and pelvic bone and soft tissue sarcomas, using mechanistic, bell-shaped and plateau models. For organs distant to the treatment field, chamber measurements recorded in an anthropomorphic phantom were used to calculate OEDs and EARs using a linear model. Ratios of OED give relative radiation-induced second cancer risks. SABR resulted in lower second cancer risks at all sites relative to 3D-CRT. FFF resulted in lower second cancer risks in out-of-field tissues relative to equivalent flattened techniques, with increasing impact in organs at greater distances from the field. For example, FFF reduced second cancer risk by up to 20% in the stomach and up to 56% in the brain, relative to the equivalent flattened technique. Relative to 10 MV 3D-CRT, 6 MV IMRT or VMAT with flattening filter increased second cancer risks in several out-of-field organs, by up to 26% and 55%, respectively. For all techniques, EARs were consistently low. The observed large relative differences between techniques, in absolute terms, were very low, highlighting the importance of considering absolute risks alongside the corresponding relative risks, since when absolute

  7. A dosimetric comparison of 3D-CRT, IMRT, and static tomotherapy with an SIB for large and small breast volumes

    SciTech Connect

    Michalski, Andrea; Atyeo, John; Cox, Jennifer; Rinks, Marianne; Morgia, Marita; Lamoury, Gillian

    2014-07-01

    Radiation therapy to the breast is a complex task, with many different techniques that can be employed to ensure adequate dose target coverage while minimizing doses to the organs at risk. This study compares the dose planning outcomes of 3 radiation treatment modalities, 3 dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and static tomotherapy, for left-sided whole-breast radiation treatment with a simultaneous integrated boost (SIB). Overall, 20 patients with left-sided breast cancer were separated into 2 cohorts, small and large, based on breast volume. Dose plans were produced for each patient using 3D-CRT, IMRT, and static tomotherapy. All patients were prescribed a dose of 45 Gy in 20 fractions to the breast with an SIB of 56 Gy in 20 fractions to the tumor bed and normalized so that D{sub 98%} > 95% of the prescription dose. Dosimetric comparisons were made between the 3 modalities and the interaction of patient size. All 3 modalities offered adequate planning target volume (PTV) coverage with D{sub 98%} > 95% and D{sub 2%} < 107%. Static tomotherapy offered significantly improved (p = 0.006) dose homogeneity to the PTV{sub boost} {sub eval} (0.079 ± 0.011) and breast minus the SIB volume (Breast{sub SIB}) (p < 0.001, 0.15 ± 0.03) compared with the PTV{sub boost} {sub eval} (0.085 ± 0.008, 0.088 ± 0.12) and Breast{sub SIB} (0.22 ± 0.05, 0.23 ± 0.03) for IMRT and 3D-CRT, respectively. Static tomotherapy also offered statistically significant reductions (p < 0.001) in doses to the ipsilateral lung mean dose of 6.79 ± 2.11 Gy compared with 7.75 ± 2.54 Gy and 8.29 ± 2.76 Gy for IMRT and 3D-CRT, respectively, and significantly (p < 0.001) reduced heart doses (mean = 2.83 ± 1.26 Gy) compared to both IMRT and 3D-CRT (mean = 3.70 ± 1.44 Gy and 3.91 ± 1.58 Gy). Static tomotherapy is the dosimetrically superior modality for the whole breast with an SIB compared with IMRT and 3D-CRT. IMRT is superior to 3D-CRT

  8. Life Years Lost – Comparing potentially fatal late complications after radiotherapy for pediatric medulloblastoma on a common scale

    PubMed Central

    Patrik Brodin, N.; Vogelius, Ivan R.; Maraldo, Maja V.; Rosenschöld, Per Munck af; Aznar, Marianne C.; Kiil-Berthelsen, Anne; Nilsson, Per; Björk-Eriksson, Thomas; Specht, Lena; Bentzen, Søren M.

    2012-01-01

    Background A framework for estimating and comparing risks of various long-term complications on a common scale is developed and applied to three different techniques for cranio-spinal irradiation of pediatric medulloblastoma patients. Methods Radiation dose-response parameters related to excess hazard ratios for secondary breast, lung, stomach and thyroid cancer, heart failure and myocardial infarction were derived from large published clinical series. Combined with age- and sex-specific hazards in the U.S. general population this yielded excess hazards of complications for a cancer survivor, as a function of attained age. After adjusting for competing risks of death, life years lost (LYL) were estimated based on excess hazard and prognosis of a complication, for 3D conformal radiotherapy (3D CRT), volumetric modulated arc therapy (VMAT) and intensity-modulated proton therapy (IMPT). Results Lung cancer contributed most to the estimated LYL, followed by myocardial infarction and stomach cancer. Breast or thyroid cancer incidence was estimated higher than lung and stomach cancer incidence but LYL was lower due to the relatively good prognosis. Estimated LYL ranged between 1.90 years for 3D CRT to 0.28 years with IMPT. In a paired comparison, IMPT was associated with significantly fewer LYL than both photon techniques. Conclusions Estimating the risk of late complications is associated with considerable uncertainty but including prognosis and attained age at an event, to obtain the more informative LYL estimate, adds relatively little to this uncertainty. PMID:22517408

  9. Optimized Volumetric Modulated Arc Therapy Versus 3D-CRT for Early Stage Mediastinal Hodgkin Lymphoma Without Axillary Involvement: A Comparison of Second Cancers and Heart Disease Risk

    SciTech Connect

    Filippi, Andrea Riccardo; Ragona, Riccardo; Piva, Cristina; Scafa, Davide; Fiandra, Christian; Fusella, Marco; Giglioli, Francesca Romana; Lohr, Frank; Ricardi, Umberto

    2015-05-01

    Purpose: The purpose of this study was to evaluate the risks of second cancers and cardiovascular diseases associated with an optimized volumetric modulated arc therapy (VMAT) planning solution in a selected cohort of stage I/II Hodgkin lymphoma (HL) patients treated with either involved-node or involved-site radiation therapy in comparison with 3-dimensional conformal radiation therapy (3D-CRT). Methods and Materials: Thirty-eight patients (13 males and 25 females) were included. Disease extent was mediastinum alone (n=8, 21.1%); mediastinum plus unilateral neck (n=19, 50%); mediastinum plus bilateral neck (n=11, 29.9%). Prescription dose was 30 Gy in 2-Gy fractions. Only 5 patients had mediastinal bulky disease at diagnosis (13.1%). Anteroposterior 3D-CRT was compared with a multiarc optimized VMAT solution. Lung, breast, and thyroid cancer risks were estimated by calculating a lifetime attributable risk (LAR), with a LAR ratio (LAR{sub VMAT}-to-LAR{sub 3D-CRT}) as a comparative measure. Cardiac toxicity risks were estimated by calculating absolute excess risk (AER). Results: The LAR ratio favored 3D-CRT for lung cancer induction risk in mediastinal alone (P=.004) and mediastinal plus unilateral neck (P=.02) presentations. LAR ratio for breast cancer was lower for VMAT in mediastinal plus bilateral neck presentations (P=.02), without differences for other sites. For thyroid cancer, no significant differences were observed, regardless of anatomical presentation. A significantly lower AER of cardiac (P=.038) and valvular diseases (P<.0001) was observed for VMAT regardless of disease extent. Conclusions: In a cohort of patients with favorable characteristics in terms of disease extent at diagnosis (large prevalence of nonbulky presentations without axillary involvement), optimized VMAT reduced heart disease risk with comparable risks of thyroid and breast cancer, with an increase in lung cancer induction probability. The results are however strongly influenced by

  10. Dosimetric evaluation of the skin-sparing effects of 3-dimensional conformal radiotherapy and intensity-modulated radiotherapy for left breast cancer.

    PubMed

    Jo, In Young; Kim, Shin-Wook; Son, Seok Hyun

    2017-01-10

    The purpose of this study was to evaluate the skin-sparing effects of 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) in patients with early left-sided breast cancer. Twenty left breast cancer patients treated with whole breast radiotherapy following breast-conserving surgery were enrolled in this study, and the 3D-CRT and IMRT plans were generated for each patient. To evaluate the dose delivered to the skin, 2 mm thickness skin (2-mm skin) and 3 mm thickness skin (3-mm skin) were contoured and a dosimetric comparison between the 2 plans was performed. The target volume coverage was better in IMRT than in 3D-CRT. The mean dose was 50.8 Gy for 3D-CRT and 51.1 Gy for IMRT. V40Gy was 99.4% for 3D-CRT and 99.9% for IMRT. In the case of skin, the mean dose was higher in 3D-CRT than in IMRT (mean dose of 2-mm skin: 32.8 Gy and 24.2 Gy; mean dose of 3-mm skin: 37.2 Gy and 27.8 Gy, for 3D-CRT and IMRT, respectively). These results indicated that the skin-sparing effect is more prominent in IMRT compared to 3D-CRT without compromising the target volume coverage.

  11. Transitioning from conventional radiotherapy to intensity-modulated radiotherapy for localized prostate cancer: changing focus from rectal bleeding to detailed quality of life analysis

    PubMed Central

    Yamazaki, Hideya; Nakamura, Satoaki; Nishimura, Takuya; Yoshida, Ken; Yoshioka, Yasuo; Koizumi, Masahiko; Ogawa, Kazuhiko

    2014-01-01

    With the advent of modern radiation techniques, we have been able to deliver a higher prescribed radiotherapy dose for localized prostate cancer without severe adverse reactions. We reviewed and analyzed the change of toxicity profiles of external beam radiation therapy (EBRT) from the literature. Late rectal bleeding is the main adverse effect, and an incidence of >20% of Grade ≥2 adverse events was reported for 2D conventional radiotherapy of up to 70 Gy. 3D conformal radiation therapy (3D-CRT) was found to reduce the incidence to ∼10%. Furthermore, intensity-modulated radiation therapy (IMRT) reduced it further to a few percentage points. However, simultaneously, urological toxicities were enhanced by dose escalation using highly precise external radiotherapy. We should pay more attention to detailed quality of life (QOL) analysis, not only with respect to rectal bleeding but also other specific symptoms (such as urinary incontinence and impotence), for two reasons: (i) because of the increasing number of patients aged >80 years, and (ii) because of improved survival with elevated doses of radiotherapy and/or hormonal therapy; age is an important prognostic factor not only for prostate-specific antigen (PSA) control but also for adverse reactions. Those factors shift the main focus of treatment purpose from survival and avoidance of PSA failure to maintaining good QOL, particularly in older patients. In conclusion, the focus of toxicity analysis after radiotherapy for prostate cancer patients is changing from rectal bleeding to total elaborate quality of life assessment. PMID:25204643

  12. SU-E-T-217: Comprehensive Dosimetric Evaluation On 3D-CRT, IMRT and Non-Coplanar Arc Treatment for Prone Accelerated Partial Breast Irradiation (APBI)

    SciTech Connect

    Chiu, T; Yan, Y; Ramirez, E; Lee, P; Jiang, S; Gu, X

    2015-06-15

    Purpose: Accelerated partial breast irradiation (APBI) is an effective treatment for early stage breast-cancer. Irradiation in a prone position can mitigate breast motion and spare heart and lung. In this study, a comprehensive study is performed to evaluate various treatment techniques for prone APBI treatment including: 3D-CRT, IMRT, co-planar and non-coplanar partial arcs treatment. Methods: In this treatment planning study, a left breast patient treated in prone position in our clinic was imported into Varian Eclipse TPS. Six beams tangential to chest wall were used in both 3D-CRT and IMRT plans. These six beams were coplanar in a transactional plane achieved by both gantry and couch rotation. A 60-beam IMRT plan was also created to explore the maximum benefit of co-planar IMRT. Within deliverable couch rotation range (±30°), partial arc treatment plans with one and up to ten couch positions were generated for comparison. For each plan, 30Gy in 6 fractions was prescribed to 95% PTV volume. Critical dosimetric parameters, such as conformity index, mean, maximum, and volume dose of organ at risk, are evaluated. Results: The conformity indexes (CI) are 3.53, 3.17, 2.21 and 1.08 respectively to 3D-CRT, 6-beam IMRT, 60-beam IMRT, and two-partial-arcs coplanar plans. However, arc plans increase heart dose. CI for non-coplanar arc plans decreases from 1.19 to 1.10 when increases couch positions. Maximum dose in ipsilateral lung (1.98 to 1.13 Gy), and heart (0.62 to 0.43 Gy) are steadily decreased with the increased number of non-coplanar arcs. Conclusions: The dosimetric evaluation results show that partial arc plans have improved CIs compared to conventional 3D-CRT and IMRT plans. Increasing number of partial arcs decreases lung and heart dose. The dosimetric benefit obtained from non-coplanar arcs should be considered with treatment delivery time.

  13. A case study of radiotherapy planning for a bilateral metal hip prosthesis prostate cancer patient

    SciTech Connect

    Su, Andy; Reft, Chester; Rash, Carla; Price, Jennifer; Jani, Ashesh B. . E-mail: jani@rover.uchicago.edu

    2005-09-30

    The purpose of this report is to communicate the observed advantage of intensity-modulated radiotherapy (IMRT) in a patient with bilateral metallic hip prostheses. In this patient with early-stage low-risk disease, a dose of 74 Gy was planned in two phases-an initial 50 Gy to the prostate and seminal vesicles and an additional 24 Gy to the prostate alone. Each coplanar beam avoided the prosthesis in the beam's eye view. Using the same target expansions for each phase, IMRT and 3D-conformal radiotherapy (CRT) plans were compared for target coverage and inhomogeneity as well as dose to the bladder and rectum. The results of the analysis demonstrated that IMRT provided superior target coverage with reduced dose to normal tissues for both individual phases of the treatment plan as well as for the composite treatment plan. The dose to the rectum was significantly reduced with the IMRT technique, with a composite V80 of 35% for the IMRT plan versus 70% for 3D-CRT plan. Similarly, the dose to the bladder was significantly reduced with a V80 of 9% versus 20%. Overall, various dosimetric parameters revealed the corresponding 3D-CRT plan would not have been acceptable. The results indicate significant success with IMRT in a clinical scenario where there were no curative alternatives for local treatment other than external beam radiotherapy. Therefore, definitive external beam radiation of prostate cancer patients with bilateral prosthesis is made feasible with IMRT. The work described herein may also have applicability to other groups of patients, such as those with gynecological or other pelvic malignancies.

  14. Late rectal bleeding after 3D-CRT for prostate cancer: development of a neural-network-based predictive model

    NASA Astrophysics Data System (ADS)

    Tomatis, S.; Rancati, T.; Fiorino, C.; Vavassori, V.; Fellin, G.; Cagna, E.; Mauro, F. A.; Girelli, G.; Monti, A.; Baccolini, M.; Naldi, G.; Bianchi, C.; Menegotti, L.; Pasquino, M.; Stasi, M.; Valdagni, R.

    2012-03-01

    The aim of this study was to develop a model exploiting artificial neural networks (ANNs) to correlate dosimetric and clinical variables with late rectal bleeding in prostate cancer patients undergoing radical radiotherapy and to compare the ANN results with those of a standard logistic regression (LR) analysis. 718 men included in the AIROPROS 0102 trial were analyzed. This multicenter protocol was characterized by the prospective evaluation of rectal toxicity, with a minimum follow-up of 36 months. Radiotherapy doses were between 70 and 80 Gy. Information was recorded for comorbidity, previous abdominal surgery, use of drugs and hormonal therapy. For each patient, a rectal dose-volume histogram (DVH) of the whole treatment was recorded and the equivalent uniform dose (EUD) evaluated as an effective descriptor of the whole DVH. Late rectal bleeding of grade ≥ 2 was considered to define positive events in this study (52 of 718 patients). The overall population was split into training and verification sets, both of which were involved in model instruction, and a test set, used to evaluate the predictive power of the model with independent data. Fourfold cross-validation was also used to provide realistic results for the full dataset. The LR was performed on the same data. Five variables were selected to predict late rectal bleeding: EUD, abdominal surgery, presence of hemorrhoids, use of anticoagulants and androgen deprivation. Following a receiver operating characteristic analysis of the independent test set, the areas under the curves (AUCs) were 0.704 and 0.655 for ANN and LR, respectively. When evaluated with cross-validation, the AUC was 0.714 for ANN and 0.636 for LR, which differed at a significance level of p = 0.03. When a practical discrimination threshold was selected, ANN could classify data with sensitivity and specificity both equal to 68.0%, whereas these values were 61.5% for LR. These data provide reasonable evidence that results obtained with

  15. Development of a Set of Nomograms to Predict Acute Lower Gastrointestinal Toxicity for Prostate Cancer 3D-CRT

    SciTech Connect

    Valdagni, Riccardo; Rancati, Tiziana Fiorino, Claudio; Fellin, Gianni; Magli, Alessandro; Baccolini, Michela; Bianchi, Carla; Cagna, Emanuela; Greco, Carlo; Mauro, Flora A.; Monti, Angelo F.; Munoz, Fernando; Stasi, Michele; Franzone, Paola; Vavassori, Vittorio

    2008-07-15

    Purpose: To predict acute Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) and Subjective Objective Signs Management and Analysis/Late Effect of Normal Tissue (SOMA/LENT) toxicities of the lower gastrointestinal (LGI) syndrome in patients with prostate cancer undergoing three-dimensional conformal radiotherapy using a tool (nomogram) that takes into account clinical and dosimetric variables that proved to be significant in the Italian Association for Radiation Oncology (AIRO) Group on Prostate Cancer (AIROPROS) 0102 trial. Methods and Materials: Acute rectal toxicity was scored in 1,132 patients by using both the RTOG/EORTC scoring system and a 10-item self-assessed questionnaire. Correlation between clinical variables/dose-volume histogram constraints and rectal toxicity was investigated by means of multivariate logistic analyses. Multivariate logistic analyses results were used to create nomograms predicting the symptoms of acute LGI syndrome. Results: Mean rectal dose was a strong predictor of Grade 2-3 RTOG/EORTC acute LGI toxicity (p 0.0004; odds ratio (OR) = 1.035), together with hemorrhoids (p = 0.02; OR 1.51), use of anticoagulants/antiaggregants (p = 0.02; OR = 0.63), and androgen deprivation (AD) (p = 0.04; OR = 0.65). Diabetes (p = 0.34; OR 1.28) and pelvic node irradiation (p = 0.11; OR = 1.56) were significant variables to adjust toxicity prediction. Bleeding was related to hemorrhoids (p = 0.02; OR = 173), AD (p = 0.17; OR = 0.67), and mean rectal dose (p 0.009; OR = 1.024). Stool frequency was related to seminal vesicle irradiation (p = 0.07; OR = 6.46), AD administered for more than 3 months (p = 0.002; OR = 0.32), and the percent volume of rectum receiving more than 60 Gy (V60Gy) V60 (p = 0.02; OR = 1.02). Severe fecal incontinence depended on seminal vesicle irradiation (p = 0.14; OR = 4.5) and V70 (p = 0.033; OR 1.029). Conclusions: To the best of our knowledge, this work presents the

  16. Dosimetric comparison of 3D conformal, IMRT, and V-MAT techniques for accelerated partial-breast irradiation (APBI).

    PubMed

    Qiu, Jian-Jian; Chang, Zheng; Horton, Janet K; Wu, Qing-Rong Jackie; Yoo, Sua; Yin, Fang-Fang

    2014-01-01

    The purpose is to dosimetrically compare the following 3 delivery techniques: 3-dimensional conformal radiation therapy (3D-CRT), intensity-modulated arc therapy (IMRT), and volumetric-modulated arc therapy (V-MAT) in the treatment of accelerated partial-breast irradiation (APBI). Overall, 16 patients with T1/2N0 breast cancer were treated with 3D-CRT (multiple, noncoplanar photon fields) on the RTOG 0413 partial-breast trial. These cases were subsequently replanned using static gantry IMRT and V-MAT technology to understand dosimetric differences among these 3 techniques. Several dosimetric parameters were used in plan quality evaluation, including dose conformity index (CI) and dose-volume histogram analysis of normal tissue coverage. Quality assurance studies including gamma analysis were performed to compare the measured and calculated dose distributions. The IMRT and V-MAT plans gave more conformal target dose distributions than the 3D-CRT plans (p < 0.05 in CI). The volume of ipsilateral breast receiving 5 and 10Gy was significantly less using the V-MAT technique than with either 3D-CRT or IMRT (p < 0.05). The maximum lung dose and the ipsilateral lung volume receiving 10 (V10) or 20Gy (V20) were significantly less with both V-MAT and IMRT (p < 0.05). The IMRT technique was superior to 3D-CRT and V-MAT of low dose distributions in ipsilateral lung (p < 0.05 in V5 and D5). The total mean monitor units (MUs) for V-MAT (621.0 ± 111.9) were 12.2% less than those for 3D-CRT (707.3 ± 130.9) and 46.5% less than those for IMRT (1161.4 ± 315.6) (p < 0.05). The average machine delivery time was 1.5 ± 0.2 minutes for the V-MAT plans, 7.0 ± 1.6 minutes for the 3D-CRT plans, and 11.5 ± 1.9 minutes for the IMRT plans, demonstrating much less delivery time for V-MAT. Based on this preliminary study, V-MAT and IMRT techniques offer improved dose conformity as compared with 3D-CRT techniques without increasing dose to the ipsilateral lung. In terms of MU and delivery

  17. Dosimetry in brain tumor phantom at 15 MV 3D conformal radiation therapy

    PubMed Central

    2013-01-01

    Glioblastoma multiforme (GBM) is the most common, aggressive, highly malignant and infiltrative of all brain tumors with low rate of control. The main goal of this work was to evaluate the spatial dose distribution into a GBM simulator inside a head phantom exposed to a 15 MV 3D conformal radiation therapy in order to validate internal doses. A head and neck phantom developed by the Ionizing Radiation Research Group (NRI) was used on the experiments. Such phantom holds the following synthetic structures: brain and spinal cord, skull, cervical and thoracic vertebrae, jaw, hyoid bone, laryngeal cartilages, head and neck muscles and skin. Computer tomography (CT) of the simulator was taken, capturing a set of contrasted references. Therapy Radiation planning (TPS) was performed based on those CT images, satisfying a 200 cGy prescribed dose split in three irradiation fields. The TPS assumed 97% of prescribed dose cover the prescribed treatment volume (PTV). Radiochromic films in a solid water phantom provided dose response as a function of optical density. Spatial dosimetric distribution was generated by radiochromic film samples at coronal, sagittal-anterior and sagittal-posterior positions, inserted into tumor simulator and brain. The spatial dose profiles held 70 to 120% of the prescribed dose. In spite of the stratified profile, as opposed to the smooth dose profile from TPS, the tumor internal doses were within a 5% deviation from 214.4 cGy evaluated by TPS. 83.2% of the points with a gamma value of less than 1 (3%/3mm) for TPS and experimental values, respectively. At the tumor, measured at coronal section, a few dark spots in the film caused the appearance of outlier points in 13-15% of dose deviation percentage. And, as final conclusion, such dosimeter choice and the physical anthropomorphic and anthropometric phantom provided an efficient method for validating radiotherapy protocols. PMID:23829593

  18. SU-E-T-393: Investigation of Hot Spots in Tomotherapy 3D Conformal Breast Plan

    SciTech Connect

    Chen, Q; Siebers, J; Khandelwal, S

    2014-06-01

    Purpose: The purpose of this study is to determine the root-cause of hotspots inherent to Tomotherapy static beam 3D conformal radiotherapy (3DCRT) for breast treatment. ASTRO (ref here) recommends that IMRT be avoided for breast treatments. Despite Tomotherapy's inherent IMRT-like optimization and delivery, our experience at a Tomotherapy-only site has been that Tomotherapy 3DCRT fail to produce a clinically acceptable plan for 79% of our breast patients. Hot-spots have been one of the major obstacles. Methods: Eight lumpectomy patients were planned according to RTOG-1005 specification. Two or four tangential beams were used for 3DCRT breast planning. To spare the contralateral breast and ipsilateral lung, part of the PTV was not covered by the primary beam, yielding adjacent hot-spots. We hypothesize that the planning system creates hotspots adjacent to the cold spots to yield scatter radiation dose compensation in the blocked region. Various phantom and patient setup were used to test the hypothesis. Results: Hot spots outside of PTV in the range of 135% - 174% were observed for patient plan. It is confirmed that the PTV partial block causes the adjacent hot spot. The root cause is the optimizer quadratic objective function over- weighs improving the cold spot. The IMRT flexibility offered by Tomotherapy is counter-productive in static-beam 3DCRT breast treatment. For phantom case, as the Modulation-Factor increases from 1.1 to 5, the hot spot increases from 110% to 300%. Limiting the 3DCRT intensity modulation is shown to produce clinically acceptable plan. Conclusion: Most of the hot spots in Tomotherapy 3DCRT breast plan originate from the planning-system optimizer attempting to cover PTV cold spots rather than from the beam energy. Altering the objective function could improve clinical acceptability of static beam Tomotherapy 3DCRT.

  19. Comparison and Limitations of DVH-Based NTCP Models Derived From 3D-CRT and IMRT Data for Prediction of Gastrointestinal Toxicities in Prostate Cancer Patients by Using Propensity Score Matched Pair Analysis

    SciTech Connect

    Troeller, Almut; Yan, Di; Marina, Ovidiu; Schulze, Derek; Alber, Markus; Parodi, Katia; Belka, Claus; Söhn, Matthias

    2015-02-01

    Purpose: This study compared normal tissue complication probability (NTCP) modeling of chronic gastrointestinal toxicities following prostate cancer treatment for 2 treatment modalities. Possible factors causing discrepancies in optimal NTCP model parameters between 3-dimensional conformal radiation therapy (3D-CRT) and intensity modulated RT (IMRT) were analyzed and discussed, including the impact of patient characteristics, image guidance, toxicity scoring bias, and NTCP model limitations. Methods and Materials: Rectal wall dose-volume histograms of 1115 patients treated for prostate cancer under an adaptive radiation therapy protocol were used to model gastrointestinal toxicity grade ≥2 (according to Common Terminology Criteria for Adverse Events). A total of 457 patients were treated with 3D-CRT and 658 with IMRT. 3D-CRT patients were matched to IMRT patients based on various patient characteristics, using a propensity score–based algorithm. Parameters of the Lyman equivalent uniform dose and cut-off dose logistic regression NTCP models were estimated for the 2 matched treatment modalities and the combined group. Results: After they were matched, the 3D-CRT and IMRT groups contained 275 and 550 patients with a large discrepancy of 28.7% versus 7.8% toxicities, respectively (P<.001). For both NTCP models, optimal parameters found for the 3D-CRT groups did not fit the IMRT patients well and vice versa. Models developed for the combined data overestimated NTCP for the IMRT patients and underestimated NTCP for the 3D-CRT group. Conclusions: Our analysis did not reveal a single definitive cause for discrepancies of model parameters between 3D-CRT and IMRT. Patient characteristics and bias in toxicity scoring, as well as image guidance alone, are unlikely causes of the large discrepancy of toxicities. Whether the cause was inherent to the specific NTCP models used in this study needs to be verified by future investigations. Because IMRT is increasingly used

  20. Conkiss: Conformal Kidneys Sparing 3D Noncoplanar Radiotherapy Treatment for Pancreatic Cancer As an Alternative to IMRT

    SciTech Connect

    Sebestyen, Zsolt; Kovacs, Peter; Gulyban, Akos; Farkas, Robert; Bellyei, Szabolcs; Liposits, Gabor; Szigeti, Andras; Esik, Olga; Derczy, Katalin; Mangel, Laszlo

    2011-04-01

    When treating pancreatic cancer using standard (ST) 3D conformal radiotherapy (3D-CRT) beam arrangements, the kidneys often receive a higher dose than their probable tolerance limit. Our aim was to elaborate a new planning method that-similarly to IMRT-effectively spares the kidneys without compromising the target coverage. Conformal kidneys sparing (CONKISS) 5-field, noncoplanar plans were compared with ST plans for 23 consecutive patients retrospectively. Optimal beam arrangements were used consisting of a left- and right-wedged beam-pair and an anteroposterior beam inclined in the caudal direction. The wedge direction determination (WEDDE) algorithm was developed to adjust the adequate direction of wedges. The aimed organs at risk (OARs) mean dose limits were: kidney <12 Gy, liver <25 Gy, small bowels <30 Gy, and spinal cord maximum <45 Gy. Conformity and homogeneity indexes with z-test were used to evaluate and compare the different planning approaches. The mean dose to the kidneys decreased significantly (p < 0.05): left kidney 7.7 vs. 10.7 Gy, right kidney 9.1 vs. 11.7 Gy. Meanwhile the mean dose to the liver increased significantly (18.1 vs. 15.0 Gy). The changes in the conformity, homogeneity, and in the doses to other OARs were not significant. The CONKISS method balances the load among the OARs and significantly reduces the dose to the kidneys, without any significant change in the conformity and homogeneity. Using 3D-CRT the CONKISS method can be a smart alternative to IMRT to enhance the possibility of dose escalation.

  1. DVE flight test results of a sensor enhanced 3D conformal pilot support system

    NASA Astrophysics Data System (ADS)

    Münsterer, Thomas; Völschow, Philipp; Singer, Bernhard; Strobel, Michael; Kramper, Patrick

    2015-06-01

    The paper presents results and findings of flight tests of the Airbus Defence and Space DVE system SFERION performed at Yuma Proving Grounds. During the flight tests ladar information was fused with a priori DB knowledge in real-time and 3D conformal symbology was generated for display on an HMD. The test flights included low level flights as well as numerous brownout landings.

  2. SU-E-T-538: Lung SBRT Dosimetric Comparison of 3D Conformal and RapidArc Planning

    SciTech Connect

    Jiang, R; Zhan, L; Osei, E

    2015-06-15

    Purpose: Dose distributions of RapidArc Plan can be quite different from standard 3D conformal radiation therapy. SBRT plans can be optimized with high conformity or mimic the 3D conformal treatment planning with very high dose in the center of the tumor. This study quantifies the dosimetric differences among 3D conformal plan; flattened beam and FFF beam RapidArc Plans for lung SBRT. Methods: Five lung cancer patients treated with 3D non-coplanar SBRT were randomly selected. All the patients were CT scanned with 4DCT to determine the internal target volume. Abdominal compression was applied to minimize respiratory motion for SBRT patients. The prescription dose was 48 Gy in 4 fractions. The PTV coverage was optimized by two groups of objective function: one with high conformity, another mimicking 3D conformal dose distribution with high dose in the center of PTV. Optimization constraints were set to meet the criteria of the RTOG-0915 protocol. All VMAT plans were optimized with the RapidArc technique using four full arcs in Eclipse treatment planning system. The RapidArc SBRT plans with flattened 6MV beam and 6MV FFF beam were generated and dosimetric results were compared with the previous treated 3D non-coplanar plans. Results: All the RapidArc plans with flattened beam and FFF beam had similar results for the PTV and OARs. For the high conformity optimization group, The DVH of PTV exhibited a steep dose fall-off outside the PTV compared to the 3D non-coplanar plan. However, for the group mimicking the 3D conformal target dose distribution, although the PTV is very similar to the 3D conformal plan, the ITV coverage is better than 3D conformal plan. Conclusion: Due to excellent clinical experiences of 3D conformal SBRT treatment, the Rapid Arc optimization mimicking 3D conformal planning may be suggested for clinical use.

  3. Use of 3D conformal symbology on HMD for a safer flight in degraded visual environment

    NASA Astrophysics Data System (ADS)

    Klein, Ofer; Doehler, Hans-Ullrich; Trousil, Thomas; Peleg-Marzan, Ruthy

    2012-06-01

    Since the entry of coalition forces to Afghanistan and Iraq, a steep rise at the rate of accidents has occurred as a result of flying and landing in Degraded Visual Environment (DVE) conditions. Such conditions exist in various areas around the world and include bad weather, dust and snow landing (Brownout and whiteout) and low illumination at dark nights. A promising solution is a novel 3D conformal symbology displayed on head-tracked helmet mounted display (HMD). The 3D conformal symbology approach provides space stabilized three-dimensional symbology presented on the pilot helmet mounted display and has the potential of presenting a step function in HMD performance. It offers an intuitive way for presenting crucial information to the pilots in order to increase Situational Awareness, lower the pilots' workload and thus enhancing safety of flight dramatically. The pilots can fly "heads out" while the necessary flight and mission information is presented in intuitive manner, conformal with the real world and in real-time. . Several Evaluation trials had been conducted in the UK, US and Israel using systems that were developed by Elbit Systems to prove the embodied potential of the system to provide a solution for DVE flight conditions: technology, concept and the specific systems.

  4. A nanofiber based artificial electronic skin with high pressure sensitivity and 3D conformability

    NASA Astrophysics Data System (ADS)

    Zhong, Weibin; Liu, Qiongzhen; Wu, Yongzhi; Wang, Yuedan; Qing, Xing; Li, Mufang; Liu, Ke; Wang, Wenwen; Wang, Dong

    2016-06-01

    Pressure sensors with 3D conformability are highly desirable components for artificial electronic skin or e-textiles that can mimic natural skin, especially for application in real-time monitoring of human physiological signals. Here, a nanofiber based electronic skin with ultra-high pressure sensitivity and 3D conformability is designed and built by interlocking two elastic patterned nanofibrous membranes. The patterned membrane is facilely prepared by casting conductive nanofiber ink into a silicon mould to form an array of semi-spheroid-like protuberances. The protuberances composed of intertwined elastic POE nanofibers and PPy@PVA-co-PE nanofibers afford a tunable effective elastic modulus that is capable of capturing varied strains and stresses, thereby contributing to a high sensitivity for pressure sensing. This electronic skin-like sensor demonstrates an ultra-high sensitivity (1.24 kPa-1) below 150 Pa with a detection limit as low as about 1.3 Pa. The pixelated sensor array and a RGB-LED light are then assembled into a circuit and show a feasibility for visual detection of spatial pressure. Furthermore, a nanofiber based proof-of-concept wireless pressure sensor with a bluetooth module as a signal transmitter is proposed and has demonstrated great promise for wireless monitoring of human physiological signals, indicating a potential for large scale wearable electronic devices or e-skin.Pressure sensors with 3D conformability are highly desirable components for artificial electronic skin or e-textiles that can mimic natural skin, especially for application in real-time monitoring of human physiological signals. Here, a nanofiber based electronic skin with ultra-high pressure sensitivity and 3D conformability is designed and built by interlocking two elastic patterned nanofibrous membranes. The patterned membrane is facilely prepared by casting conductive nanofiber ink into a silicon mould to form an array of semi-spheroid-like protuberances. The

  5. Predictors for Rectal and Intestinal Acute Toxicities During Prostate Cancer High-Dose 3D-CRT: Results of a Prospective Multicenter Study

    SciTech Connect

    Vavassori, Vittorio; Fiorino, Claudio . E-mail: fiorino.claudio@hsr.it; Rancati, Tiziana; Magli, Alessandro; Fellin, Gianni; Baccolini, Michela; Bianchi, Carla; Cagna, Emanuela; Mauro, Flora A.; Monti, Angelo F.; Munoz, Fernando; Stasi, Michele; Franzone, Paola; Valdagni, Riccardo

    2007-04-01

    Purpose: To find predictors for rectal and intestinal acute toxicity in patients with prostate cancer treated with {>=}70 Gy conformal radiotherapy. Methods and Materials: Between July 2002 and March 2004, 1,132 patients were entered into a cooperative study (AIROPROS01-02). Toxicity was scored using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scale and by considering the changes (before and after treatment) of the scores of a self-administered questionnaire on rectal/intestinal toxicity. The correlation with a number of parameters was assessed by univariate and multivariate analyses. Concerning the questionnaire, only moderate/severe complications were considered. Results: Of 1,132 patients, 1,123 were evaluable. Of these patients, 375, 265, and 28 had Grade 1, 2, and 3 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer toxicity, respectively. The mean rectal dose was the most predictive parameter (p = 0.0004; odds ratio, 1.035) for Grade 2 or worse toxicity, and the use of anticoagulants/antiaggregants (p 0.02; odds ratio, 0.63) and hormonal therapy (p = 0.04, odds ratio, 0.65) were protective. The questionnaire-based scoring revealed that a greater mean rectal dose was associated with a greater risk of bleeding; larger irradiated volumes were associated with frequency, tenesmus, incontinence, and bleeding; hormonal therapy was protective against frequency and tenesmus; hemorrhoids were associated with a greater risk of tenesmus and bleeding; and diabetes associated highly with diarrhea. Conclusion: The mean rectal dose correlated with acute rectal/intestinal toxicity in three-dimensional conformal radiotherapy for prostate cancer, and hormonal therapy and the use of anticoagulants/antiaggregants were protective. According to the moderate/severe injury scores on the self-assessed questionnaire, several clinical and dose-volume parameters were independently predictive for

  6. Clinical and Dosimetric Predictors of Late Rectal Syndrome After 3D-CRT for Localized Prostate Cancer: Preliminary Results of a Multicenter Prospective Study

    SciTech Connect

    Fiorino, Claudio Fellin, Gianni; Rancati, Tiziana; Vavassori, Vittorio; Bianchi, Carla; Borca, Valeria Casanova; Girelli, Giuseppe; Mapelli, Marco; Menegotti, Loris; Nava, Simona; Valdagni, Riccardo

    2008-03-15

    Purpose: To assess the predictors of late rectal toxicity in a prospectively investigated group of patients treated at 70-80 Gy for prostate cancer (1.8-2 Gy fractions) with three-dimensional conformal radiotherapy. Methods and Materials: A total of 1,132 patients were entered into the study between 2002 and 2004. Three types of rectal toxicity, evaluated by a self-administered questionnaire, mainly based on the subjective objective management, analytic late effects of normal tissue system, were considered: stool frequency/tenesmus/pain, fecal incontinence, and bleeding. The data from 506 patients with a follow-up of 24 months were analyzed. The correlation between a number of clinical and dosimetric parameters and Grade 2 or greater toxicity was investigated by univariate and multivariate (MVA) logistic analyses. Results: Of the 1,132 patients, 21, 15, and 30 developed stool frequency/tenesmus/pain, fecal incontinence, and bleeding, respectively. Stool frequency/tenesmus/pain correlated with previous abdominal/pelvic surgery (MVA, p = 0.05, odds ratio [OR], 3.3). With regard to incontinence, MVA showed the volume receiving {>=}40 Gy (V{sub 40}) (p = 0.035, OR, 1.037) and surgery (p = 0.02, OR, 4.4) to be the strongest predictors. V{sub 40} to V{sub 70} were highly predictive of bleeding; V{sub 70} showed the strongest impact on MVA (p = 0.03), together with surgery (p = 0.06, OR, 2.5), which was also the main predictor of Grade 3 bleeding (p = 0.02, OR, 4.2). Conclusions: The predictive value of the dose-volume histogram was confirmed for bleeding, consistent with previously suggested constraints (V{sub 50} <55%, V{sub 60} <40%, V{sub 70} <25%, and V{sub 75} <5%). A dose-volume histogram constraint for incontinence can be suggested (V{sub 40} <65-70%). Previous abdominal/pelvic surgery correlated with all toxicity types; thus, a modified constraint for bleeding (V{sub 70} <15%) can be suggested for patients with a history of abdominal/pelvis surgery, although

  7. Implications of free breathing motion assessed by 4D-computed tomography on the delivered dose in radiotherapy for esophageal cancer

    SciTech Connect

    Duma, Marciana Nona; Berndt, Johannes; Rondak, Ina-Christine; Devecka, Michal; Wilkens, Jan J.; Geinitz, Hans; Combs, Stephanie Elisabeth; Oechsner, Markus

    2015-01-01

    The aim of this study was to assess the effect of breathing motion on the delivered dose in esophageal cancer 3-dimensional (3D)-conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), and volumetric modulated arc therapy (VMAT). We assessed 16 patients with esophageal cancer. All patients underwent 4D-computed tomography (4D-CT) for treatment planning. For each of the analyzed patients, 1 3D-CRT, 1 IMRT, and 1 VMAT (RapidArc—RA) plan were calculated. Each of the 3 initial plans was recalculated on the 4D-CT (for the maximum free inspiration and maximum free expiration) to assess the effect of breathing motion. We assessed the minimum dose (D{sub min}) and mean dose (D{sub mean}) to the esophagus within the planning target volume, the volume changes of the lungs, the D{sub mean} and the total lung volume receiving at least 40 Gy (V{sub 40}), and the V{sub 30}, V{sub 20}, V{sub 10}, and V{sub 5}. For the heart we assessed the D{sub mean} and the V{sub 25}. Over all techniques and all patients the change in D{sub mean} as compared with the planned D{sub mean} (planning CT [PCT]) to the esophagus was 0.48% in maximum free inspiration (CT-insp) and 0.55% in maximum free expiration (CT-exp). The D{sub min} CT-insp change was 0.86% and CT-exp change was 0.89%. The D{sub mean} change of the lungs (heart) was in CT-insp 1.95% (2.89%) and 3.88% (2.38%) in CT-exp. In all, 4 patients had a clinically relevant change of the dose (≥ 5% D{sub mean} to the heart and the lungs) between inspiration and expiration. These patients had a very cranially or caudally situated tumor. There are no relevant differences in the delivered dose to the regions of interest among the 3 techniques. Breathing motion management could be considered to achieve a better sparing of the lungs or heart in patients with cranially or caudally situated tumors.

  8. Conformal Therapy Improves the Therapeutic Index of Patients with Anal Canal Cancer Treated with Combined Chemotherapy and External Beam Radiotherapy

    SciTech Connect

    Vuong, Te . E-mail: te.vuong@muhc.mcgill.ca; Kopek, Neil; Ducruet, Thierry; Portelance, Lorraine; Faria, Sergio; Bahoric, Boris; Devic, Slobodan

    2007-04-01

    Purpose: To evaluate the clinical outcomes of three-dimensional conformal radiotherapy (3D-CRT) in patients with anal canal cancer, in terms of local control (LC), freedom from relapse (FFR), and overall survival (OS) rates, and to estimate long-term toxicity data. Methods and Materials: Sixty historical patients, treated with conventional radiation techniques (C-RT), were used as controls, and 62 consecutive patients were treated with 3D-CRT. Patients treated with 3D-CRT received 54 Gy in 30 fractions delivered continuously, compared with 45-58.9 Gy (median dose, 54 Gy) in a split course in patients treated with C-RT. Chemotherapy consisted of 5-fluorouracil with either mitomycin-C or cis-platinum given concurrently with radiation. Survival curves were performed using the Kaplan-Meier model, and the Cox proportional hazards model was used for multivariate analysis of risk factors. Results: No differences in stage and age distribution were observed between the two groups. Patients treated with 3D-CRT and C-RT had an actuarial 5-year LC rate of 85.1% and 61.1%, respectively (p = 0.0056); the FFR rate was 70.2% and 46.1% (p = 0.0166), and the OS rate was 80.7% and 53.9% (p = 0.0171). In multivariate analysis, factors of significance for LC were nodal (N) status (p < 0.001); for OS, 3D-CRT (p = 0.038), N status (p 0.011), and T status (p = 0.012); and for FFR, 3D-CRT (p = 0.024) and N status (p < 0.001). Conclusion: The use of 3D-CRT allows patients with anal canal cancer to complete radiation and chemotherapy without interruption for toxicity, with significant improvements in LC, FFR, and OS.

  9. Intensity-Modulated Radiotherapy Reduces Gastrointestinal Toxicity in Patients Treated With Androgen Deprivation Therapy for Prostate Cancer

    SciTech Connect

    Sharma, Navesh K.; Li Tianyu; Chen, David Y.; Pollack, Alan; Horwitz, Eric M.; Buyyounouski, Mark K.

    2011-06-01

    Purpose: Androgen deprivation therapy (AD) has been shown to increase late Grade 2 or greater rectal toxicity when used concurrently with three-dimensional conformal radiotherapy (3D-CRT). Intensity-modulated radiotherapy (IMRT) has the potential to reduce toxicity by limiting the radiation dose received by the bowel and bladder. The present study compared the genitourinary and gastrointestinal (GI) toxicity in men treated with 3D-CRT+AD vs. IMRT+AD. Methods and Materials: Between July 1992 and July 2004, 293 men underwent 3D-CRT (n = 170) or IMRT (n = 123) with concurrent AD (<6 months, n = 123; {>=}6 months, n = 170). The median radiation dose was 76 Gy for 3D-CRT (International Commission on Radiation Units and Measurements) and 76 Gy for IMRT (95% to the planning target volume). Toxicity was assessed by a patient symptom questionnaire that was completed at each visit and recorded using a Fox Chase Modified Late Effects Normal Tissue Task radiation morbidity scale. Results: The mean follow-up was 86 months (standard deviation, 29.3) for the 3D-CRT group and 40 months (standard deviation, 9.7) for the IMRT group. Acute GI toxicity (odds ratio, 4; 95% confidence interval, 1.6-11.7; p = .005) was significantly greater with 3D-CRT than with IMRT and was independent of the AD duration (i.e., <6 vs. {>=}6 months). The interval to the development of late GI toxicity was significantly longer in the IMRT group. The 5-year Kaplan-Meier estimate for Grade 2 or greater GI toxicity was 20% for 3D-CRT and 8% for IMRT (p = .01). On multivariate analysis, Grade 2 or greater late GI toxicity (hazard ratio, 2.1; 95% confidence interval, 1.1-4.3; p = .04) was more prevalent in the 3D-CRT patients. Conclusion: Compared with 3D-CRT, IMRT significantly decreased the acute and late GI toxicity in patients treated with AD.

  10. SU-E-T-632: A Dosimetric Comparison of the 3D-CRT Planning of Chest Wall in Post-Mastectomy Breast Cancer Patients, with and Without Breast Board Setup

    SciTech Connect

    Muzaffar, Ambreen; Masood, Asif; Ullah, Haseeb; Mehmood, Kashif; Qasim, Uzma; Afridi, M. Ali; Khan, Salim; Hameed, Abdul

    2014-06-15

    Purpose: Breast boards are used in breast radiation which increases normal lung and heart doses, when supraclavicular field is included. Therefore, in this study through dose volume histogram (DVHs), lung and heart doses comparison was done between two different setups i.e. with and without breast board, for the treatment of left chest wall and supraclavicular fossa in postmastectomy left breast cancer. Methods: In this study, CT-Simulation scans of ten breast cancer patients were done with and without breast board, at Shifa International Hospitals Islamabad, to investigate the differences between the two different setups of the irradiation of left chest wall in terms of lung and heart doses. For immobilization, support under the neck, shoulders and arms was used. Precise PLAN 2.15 treatment planning system (TPS) was used for 3D-CRT planning. The total prescribed dose for both the plans was 5000 cGy/25 fractions. The chest wall was treated with a pair of tangential photon fields and the upper supraclavicular nodal regions were treated with an anterior photon field. A mono-isocentric technique was used to match the tangential fields with the anterior field at the isocentre. The dose volume histogram was used to compare the doses of heart and ipsilateral lung. Results: Both the plans of each patient were generated and compared. DVH results showed that for the same PTV dose coverage, plans without breast board resulted in a reduction of lung and heart doses compared with the plans with breast board. There was significant reductions in V20, V<25 and mean doses for lung and V<9 and mean doses for heart. Conclusion: In comparison of both the plans, setup without breast board significantly reduced the dose-volume of the ipsilateral lung and heart in left chest wall patients. Waived registration request has been submitted.

  11. Propensity Score-based Comparison of Long-term Outcomes With 3-Dimensional Conformal Radiotherapy vs Intensity-Modulated Radiotherapy for Esophageal Cancer

    SciTech Connect

    Lin, Steven H.; Wang Lu; Myles, Bevan; Thall, Peter F.; Hofstetter, Wayne L.; Swisher, Stephen G.; Ajani, Jaffer A.; Cox, James D.; Komaki, Ritsuko; Liao Zhongxing

    2012-12-01

    Purpose: Although 3-dimensional conformal radiotherapy (3D-CRT) is the worldwide standard for the treatment of esophageal cancer, intensity modulated radiotherapy (IMRT) improves dose conformality and reduces the radiation exposure to normal tissues. We hypothesized that the dosimetric advantages of IMRT should translate to substantive benefits in clinical outcomes compared with 3D-CRT. Methods and Materials: An analysis was performed of 676 nonrandomized patients (3D-CRT, n=413; IMRT, n=263) with stage Ib-IVa (American Joint Committee on Cancer 2002) esophageal cancers treated with chemoradiotherapy at a single institution from 1998-2008. An inverse probability of treatment weighting and inclusion of propensity score (treatment probability) as a covariate were used to compare overall survival time, interval to local failure, and interval to distant metastasis, while accounting for the effects of other clinically relevant covariates. The propensity scores were estimated using logistic regression analysis. Results: A fitted multivariate inverse probability weighted-adjusted Cox model showed that the overall survival time was significantly associated with several well-known prognostic factors, along with the treatment modality (IMRT vs 3D-CRT, hazard ratio 0.72, P<.001). Compared with IMRT, 3D-CRT patients had a significantly greater risk of dying (72.6% vs 52.9%, inverse probability of treatment weighting, log-rank test, P<.0001) and of locoregional recurrence (P=.0038). No difference was seen in cancer-specific mortality (Gray's test, P=.86) or distant metastasis (P=.99) between the 2 groups. An increased cumulative incidence of cardiac death was seen in the 3D-CRT group (P=.049), but most deaths were undocumented (5-year estimate, 11.7% in 3D-CRT vs 5.4% in IMRT group, Gray's test, P=.0029). Conclusions: Overall survival, locoregional control, and noncancer-related death were significantly better after IMRT than after 3D-CRT. Although these results need

  12. WE-G-BRB-02: The Role of Program Project Grants in Study of 3D Conformal Therapy, Dose Escalation and Motion Management

    SciTech Connect

    Fraass, B.

    2015-06-15

    Over the past 20 years the NIH has funded individual grants, program projects grants, and clinical trials which have been instrumental in advancing patient care. The ways that each grant mechanism lends itself to the different phases of translating research into clinical practice will be described. Major technological innovations, such as IMRT and proton therapy, have been advanced with R01-type and P01-type funding and will be discussed. Similarly, the role of program project grants in identifying and addressing key hypotheses on the potential of 3D conformal therapy, normal tissue-guided dose escalation and motion management will be described. An overview will be provided regarding how these technological innovations have been applied to multi-institutional NIH-sponsored trials. Finally, the panel will discuss regarding which research questions should be funded by the NIH to inspire the next advances in radiation therapy. Learning Objectives: Understand the different funding mechanisms of the NIH Learn about research advances that have led to innovation in delivery Review achievements due to NIH-funded program project grants in radiotherapy over the past 20 years Understand example advances achieved with multi-institutional clinical trials NIH.

  13. Intensity-Modulated Radiotherapy Causes Fewer Side Effects than Three-Dimensional Conformal Radiotherapy When Used in Combination With Brachytherapy for the Treatment of Prostate Cancer

    SciTech Connect

    Forsythe, Kevin; Blacksburg, Seth; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To measure the benefits of intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3D-CRT) when used in combination with brachytherapy for the treatment of prostate cancer. Methods and Materials: We conducted a retrospective review of all patients with localized prostate cancer who received external-beam radiotherapy (EBRT) in combination with brachytherapy with at least 1 year follow-up (n = 812). Combination therapy consisted of {sup 103}Pd or {sup 125}I implant, followed by a course of EBRT. From 1993 to March 2003 521 patients were treated with 3D-CRT, and from April 2003 to March 2009 291 patients were treated with IMRT. Urinary symptoms were prospectively measured with the International Prostate Symptom Score questionnaire with a single quality of life (QOL) question; rectal bleeding was assessed per the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. The Pearson {chi}{sup 2} test was used to compare toxicities experienced by patients who were treated with either IMRT or 3D-CRT. Logistic regression analyses were also performed to rule out possible confounding factors. Results: Within the first 3 months after treatment, patients treated with 3D-CRT scored their urinary symptoms as follows: 19% mild, 44% moderate, and 37% severe; patients treated with IMRT scored their urinary symptoms as follows: 36% mild, 47% moderate, and 17% severe (p < 0.001). The 3D-CRT patients rated their QOL as follows: 35% positive, 20% neutral, and 45% negative; IMRT patients rated their QOL as follows: 51% positive, 18% neutral, and 31% negative (p < 0.001). After 1 year of follow-up there was no longer any difference in urinary morbidity between the two groups. Logistic regression confirmed the differences in International Prostate Symptom Score and QOL in the acute setting (p < 0.001 for both). Grade {>=}2 rectal bleeding was reported by 11% of 3D-CRT

  14. Intensity-Modulated Radiotherapy Might Increase Pneumonitis Risk Relative to Three-Dimensional Conformal Radiotherapy in Patients Receiving Combined Chemotherapy and Radiotherapy: A Modeling Study of Dose Dumping

    SciTech Connect

    Vogelius, Ivan S.; Westerly, David C.; Cannon, George M.; Mackie, Thomas R.; Mehta, Minesh P.; Sugie, Chikao; Bentzen, Soren M.

    2011-07-01

    Purpose: To model the possible interaction between cytotoxic chemotherapy and the radiation dose distribution with respect to the risk of radiation pneumonitis. Methods and Materials: A total of 18 non-small-cell lung cancer patients previously treated with helical tomotherapy at the University of Wisconsin were selected for the present modeling study. Three treatment plans were considered: the delivered tomotherapy plans; a three-dimensional conformal radiotherapy (3D-CRT) plan; and a fixed-field intensity-modulated radiotherapy (IMRT) plan. The IMRT and 3D-CRT plans were generated specifically for the present study. The plans were optimized without adjusting for the chemotherapy effect. The effect of chemotherapy was modeled as an independent cell killing process by considering a uniform chemotherapy equivalent radiation dose added to all voxels of the organ at risk. The risk of radiation pneumonitis was estimated for all plans using the Lyman and the critical volume models. Results: For radiotherapy alone, the critical volume model predicts that the two IMRT plans are associated with a lower risk of radiation pneumonitis than the 3D-CRT plan. However, when the chemotherapy equivalent radiation dose exceeds a certain threshold, the radiation pneumonitis risk after IMRT is greater than after 3D-CRT. This threshold dose is in the range estimated from clinical chemoradiotherapy data sets. Conclusions: Cytotoxic chemotherapy might affect the relative merit of competing radiotherapy plans. More work is needed to improve our understanding of the interaction between chemotherapy and the radiation dose distribution in clinical settings.

  15. Dosimetric Comparison of Involved-Field Three-Dimensional Conformal Photon Radiotherapy and Breast-Sparing Proton Therapy for the Treatment of Hodgkin's Lymphoma in Female Pediatric Patients

    SciTech Connect

    Andolino, David L.; Hoene, Ted; Xiao, Lu; Buchsbaum, Jeffrey; Chang, Andrew L.

    2011-11-15

    Purpose: To assess the potential reduction in breast dose for young girls with Hodgkin's lymphoma (HL) treated with breast-sparing proton therapy (BS-PT) as compared with three-dimensional conformal involved-field photon radiotherapy (3D-CRT). Methods and Materials: The Clarian Health Cancer Registry was queried for female pediatric patients with the diagnosis of HL who received radiotherapy at the Indiana University Simon Cancer Center during 2006-2009. The original CT simulation images were obtained, and 3D-CRT and BS-PT plans delivering 21 Gy or cobalt gray equivalent (CGE) in 14 fractions were created for each patient. Dose-volume histogram data were collected for both 3D-CRT and BS-PT plans and compared by paired t test for correlated samples. Results: The cancer registry provided 10 female patients with Ann Arbor Stage II HL, aged 10-18 years at the time of treatment. Both mean and maximum breast dose were significantly less with BS-PT compared with 3D-CRT: 0.95 CGE vs. 4.70 Gy (p < 0.001) and 21.07 CGE vs. 23.11 Gy (p < 0.001), respectively. The volume of breast receiving 1.0 Gy/CGE and 5.0 Gy/CGE was also significantly less with BS-PT, 194 cm{sup 3} and 93 cm{sup 3}, respectively, compared with 790 cm{sup 3} and 360 cm{sup 3} with 3D-CRT (p = 0.009, 0.013). Conclusion: Breast-sparing proton therapy has the potential to reduce unnecessary breast dose in young girls with HL by as much as 80% relative to involved-field 3D-CRT.

  16. Volumetric modulated arc radiotherapy for esophageal cancer

    SciTech Connect

    Vivekanandan, Nagarajan; Sriram, Padmanaban; Syam Kumar, S.A.; Bhuvaneswari, Narayanan; Saranya, Kamalakannan

    2012-04-01

    A treatment planning study was performed to evaluate the performance of volumetric arc modulation with RapidArc (RA) against 3D conformal radiation therapy (3D-CRT) and conventional intensity-modulated radiation therapy (IMRT) techniques for esophageal cancer. Computed tomgraphy scans of 10 patients were included in the study. 3D-CRT, 4-field IMRT, and single-arc and double-arc RA plans were generated with the aim to spare organs at risk (OAR) and healthy tissue while enforcing highly conformal target coverage. The planning objective was to deliver 54 Gy to the planning target volume (PTV) in 30 fractions. Plans were evaluated based on target conformity and dose-volume histograms of organs at risk (lung, spinal cord, and heart). The monitor unit (MU) and treatment delivery time were also evaluated to measure the treatment efficiency. The IMRT plan improves target conformity and spares OAR when compared with 3D-CRT. Target conformity improved with RA plans compared with IMRT. The mean lung dose was similar in all techniques. However, RA plans showed a reduction in the volume of the lung irradiated at V{sub 20Gy} and V{sub 30Gy} dose levels (range, 4.62-17.98%) compared with IMRT plans. The mean dose and D{sub 35%} of heart for the RA plans were better than the IMRT by 0.5-5.8%. Mean V{sub 10Gy} and integral dose to healthy tissue were almost similar in all techniques. But RA plans resulted in a reduced low-level dose bath (15-20 Gy) in the range of 14-16% compared with IMRT plans. The average MU needed to deliver the prescribed dose by RA technique was reduced by 20-25% compared with IMRT technique. The preliminary study on RA for esophageal cancers showed improvements in sparing OAR and healthy tissue with reduced beam-on time, whereas only double-arc RA offered improved target coverage compared with IMRT and 3D-CRT plans.

  17. Craniospinal Irradiation Techniques: A Dosimetric Comparison of Proton Beams With Standard and Advanced Photon Radiotherapy

    SciTech Connect

    Yoon, Myonggeun; Shin, Dong Ho; Kim, Jinsung; Kim, Jong Won; Kim, Dae Woong; Park, Sung Yong; Lee, Se Byeong; Kim, Joo Young; Park, Hyeon-Jin; Park, Byung Kiu; Shin, Sang Hoon

    2011-11-01

    Purpose: To evaluate the dosimetric benefits of advanced radiotherapy techniques for craniospinal irradiation in cancer in children. Methods and Materials: Craniospinal irradiation (CSI) using three-dimensional conformal radiotherapy (3D-CRT), tomotherapy (TOMO), and proton beam treatment (PBT) in the scattering mode was planned for each of 10 patients at our institution. Dosimetric benefits and organ-specific radiation-induced cancer risks were based on comparisons of dose-volume histograms (DVHs) and on the application of organ equivalent doses (OEDs), respectively. Results: When we analyzed the organ-at-risk volumes that received 30%, 60%, and 90% of the prescribed dose (PD), we found that PBT was superior to TOMO and 3D-CRT. On average, the doses delivered by PBT to the esophagus, stomach, liver, lung, pancreas, and kidney were 19.4 Gy, 0.6 Gy, 0.3 Gy, 2.5 Gy, 0.2 Gy, and 2.2 Gy for the PD of 36 Gy, respectively, which were significantly lower than the doses delivered by TOMO (22.9 Gy, 4.5 Gy, 6.1 Gy, 4.0 Gy, 13.3 Gy, and 4.9 Gy, respectively) and 3D-CRT (34.6 Gy, 3.6 Gy, 8.0 Gy, 4.6 Gy, 22.9 Gy, and 4.3 Gy, respectively). Although the average doses delivered by PBT to the chest and abdomen were significantly lower than those of 3D-CRT or TOMO, these differences were reduced in the head-and-neck region. OED calculations showed that the risk of secondary cancers in organs such as the stomach, lungs, thyroid, and pancreas was much higher when 3D-CRT or TOMO was used than when PBT was used. Conclusions: Compared with photon techniques, PBT showed improvements in most dosimetric parameters for CSI patients, with lower OEDs to organs at risk.

  18. Integral dose and radiation-induced secondary malignancies: comparison between stereotactic body radiation therapy and three-dimensional conformal radiotherapy.

    PubMed

    D'Arienzo, Marco; Masciullo, Stefano G; de Sanctis, Vitaliana; Osti, Mattia F; Chiacchiararelli, Laura; Enrici, Riccardo M

    2012-11-19

    The aim of the present paper is to compare the integral dose received by non-tumor tissue (NTID) in stereotactic body radiation therapy (SBRT) with modified LINAC with that received by three-dimensional conformal radiotherapy (3D-CRT), estimating possible correlations between NTID and radiation-induced secondary malignancy risk. Eight patients with intrathoracic lesions were treated with SBRT, 23 Gy × 1 fraction. All patients were then replanned for 3D-CRT, maintaining the same target coverage and applying a dose scheme of 2 Gy × 32 fractions. The dose equivalence between the different treatment modalities was achieved assuming α/β = 10 Gy for tumor tissue and imposing the same biological effective dose (BED) on the target (BED = 76 Gy(10)). Total NTIDs for both techniques was calculated considering α/β = 3 Gy for healthy tissue. Excess absolute cancer risk (EAR) was calculated for various organs using a mechanistic model that includes fractionation effects. A paired two-tailed Student t-test was performed to determine statistically significant differences between the data (p ≤ 0.05). Our study indicates that despite the fact that for all patients integral dose is higher for SBRT treatments than 3D-CRT (p = 0.002), secondary cancer risk associated to SBRT patients is significantly smaller than that calculated for 3D-CRT (p = 0.001). This suggests that integral dose is not a good estimator for quantifying cancer induction. Indeed, for the model and parameters used, hypofractionated radiotherapy has the potential for secondary cancer reduction. The development of reliable secondary cancer risk models seems to be a key issue in fractionated radiotherapy. Further assessments of integral doses received with 3D-CRT and other special techniques are also strongly encouraged.

  19. Decreasing Temporal Lobe Dose With Five-Field Intensity-Modulated Radiotherapy for Treatment of Pituitary Macroadenomas

    SciTech Connect

    Parhar, Preeti K.; Duckworth, Tamara; Shah, Parinda; DeWyngaert, J. Keith; Narayana, Ashwatha; Formenti, Silvia C.; Shah, Jinesh N.

    2010-10-01

    Purpose: To compare temporal lobe dose delivered by three pituitary macroadenoma irradiation techniques: three-field three-dimensional conformal radiotherapy (3D-CRT), three-field intensity-modulated radiotherapy (3F IMRT), and a proposed novel alternative of five-field IMRT (5F IMRT). Methods and Materials: Computed tomography-based external beam radiotherapy planning was performed for 15 pituitary macroadenoma patients treated at New York University between 2002 and 2007 using: 3D-CRT (two lateral, one midline superior anterior oblique [SAO] beams), 3F IMRT (same beam angles), and 5F IMRT (same beam angles with additional right SAO and left SAO beams). Prescription dose was 45 Gy. Target volumes were: gross tumor volume (GTV) = macroadenoma, clinical target volume (CTV) = GTV, and planning target volume = CTV + 0.5 cm. Structure contouring was performed by two radiation oncologists guided by an expert neuroradiologist. Results: Five-field IMRT yielded significantly decreased temporal lobe dose delivery compared with 3D-CRT and 3F IMRT. Temporal lobe sparing with 5F IMRT was most pronounced at intermediate doses: mean V25Gy (% of total temporal lobe volume receiving {>=}25 Gy) of 13% vs. 28% vs. 29% for right temporal lobe and 14% vs. 29% vs. 30% for left temporal lobe for 5F IMRT, 3D-CRT, and 3F IMRT, respectively (p < 10{sup -7} for 5F IMRT vs. 3D-CRT and 5F IMRT vs. 3F IMRT). Five-field IMRT plans did not compromise target coverage, exceed normal tissue dose constraints, or increase estimated brain integral dose. Conclusions: Five-field IMRT irradiation technique results in a statistically significant decrease in the dose to the temporal lobes and may thus help prevent neurocognitive sequelae in irradiated pituitary macroadenoma patients.

  20. A Bayesian mixture model relating dose to critical organs and functional complication in 3D conformal radiation therapy.

    PubMed

    Johnson, Timothy D; Taylor, Jeremy M G; Ten Haken, Randall K; Eisbruch, Avraham

    2005-10-01

    A goal of cancer radiation therapy is to deliver maximum dose to the target tumor while minimizing complications due to irradiation of critical organs. Technological advances in 3D conformal radiation therapy has allowed great strides in realizing this goal; however, complications may still arise. Critical organs may be adjacent to tumors or in the path of the radiation beam. Several mathematical models have been proposed that describe the relationship between dose and observed functional complication; however, only a few published studies have successfully fit these models to data using modern statistical methods which make efficient use of the data. One complication following radiation therapy of head and neck cancers is the patient's inability to produce saliva. Xerostomia (dry mouth) leads to high susceptibility to oral infection and dental caries and is, in general, unpleasant and an annoyance. We present a dose-damage-injury model that subsumes any of the various mathematical models relating dose to damage. The model is a nonlinear, longitudinal mixed effects model where the outcome (saliva flow rate) is modeled as a mixture of a Dirac measure at zero and a gamma distribution whose mean is a function of time and dose. Bayesian methods are used to estimate the relationship between dose delivered to the parotid glands and the observational outcome-saliva flow rate. A summary measure of the dose-damage relationship is modeled and assessed by a Bayesian chi(2) test for goodness-of-fit.

  1. Intensity-modulated radiotherapy for lymphoma involving the mediastinum

    SciTech Connect

    Goodman, Karyn A.; Toner, Sean; Hunt, Margie; Wu, Elisa J.; Yahalom, Joachim . E-mail: yahalomj@mskcc.org

    2005-05-01

    Purpose: To determine the feasibility, potential advantage, and indications for intensity-modulated radiotherapy (IMRT) in the treatment of Hodgkin's lymphoma or non-Hodgkin's lymphoma involving excessively large mediastinal disease volumes or requiring repeat RT. Methods and materials: Sixteen patients with Hodgkin's lymphoma (n = 11) or non-Hodgkin's lymphoma (n = 5) undergoing primary radiotherapy or repeat RT delivered via an IMRT plan were studied. The indications for using an IMRT plan were previous mediastinal RT (n = 5) or extremely large mediastinal treatment volumes (n 11). For each patient, IMRT, conventional parallel-opposed (AP-PA), and three-dimensional conformal (3D-CRT) plans were designed using 6-MV X-rays to deliver doses ranging from 18 to 45 Gy (median, 36 Gy). The plans were compared with regard to dose-volume parameters. The IMRT/AP-PA and IMRT/3D-CRT ratios were calculated for each parameter. Results: For all patients, the mean lung dose was reduced using IMRT, on average, by 12% compared with AP-PA and 14% compared with 3D-CRT. The planning target volume coverage was also improved using IMRT compared with AP-PA but was not different from the planning target volume coverage obtained with 3D-CRT. Conclusion: In selected patients with Hodgkin's lymphoma and non-Hodgkin's lymphoma involving the mediastinum, IMRT provides improved planning target volume coverage and reduces pulmonary toxicity parameters. It is feasible for RT of large treatment volumes and allows repeat RT of relapsed disease without exceeding cord tolerance. Additional follow-up is necessary to determine whether improvements in dose delivery affect long-term morbidity and disease control.

  2. SU-E-T-356: Efficient Segmentation of Flattening Filter Free Photon Beamsfor 3D-Conformal SBRT Treatment Planning

    SciTech Connect

    Barbiere, J; Beninati, G; Ndlovu, A

    2015-06-15

    Purpose: It has been argued that a 3D-conformal technique (3DCRT) is suitable for SBRT due to its simplicity for non-coplanar planning and delivery. It has also been hypothesized that a high dose delivered in a short time can enhance indirect cell death due to vascular damage as well as limiting intrafraction motion. Flattening Filter Free (FFF) photon beams are ideal for high dose rate treatment but their conical profiles are not ideal for 3DCRT. The purpose of our work is to present a method to efficiently segment an FFF beam for standard 3DCRT planning. Methods: A 10×10 cm Varian True Beam 6X FFF beam profile was analyzed using segmentation theory to determine the optimum segmentation intensity required to create an 8 cm uniform dose profile. Two segments were automatically created in sequence with a Varian Eclipse treatment planning system by converting isodoses corresponding to the calculated segmentation intensity to contours and applying the “fit and shield” tool. All segments were then added to the FFF beam to create a single merged field. Field blocking can be incorporated but was not used for clarity. Results: Calculation of the segmentation intensity using an algorithm originally proposed by Xia and Verhey indicated that each segment should extend to the 92% isodose. The original FFF beam with 100% at the isocenter at a depth of 10 cm was reduced to 80% at 4cm from the isocenter; the segmented beam had +/−2.5 % uniformity up to 4.4cm from the isocenter. An additional benefit of our method is a 50% decrease in the 80%-20% penumbra of 0.6cm compared to 1.2cm in the original FFF beam. Conclusion: Creation of two optimum segments can flatten a FFF beam and also reduce its penumbra for clinical 3DCRT SBRT treatment.

  3. Theoretical Analysis of the Accuracy and Safety of MRI-Guided Transurethral 3-D Conformal Ultrasound Prostate Therapy

    NASA Astrophysics Data System (ADS)

    Burtnyk, Mathieu; Chopra, Rajiv; Bronskill, Michael

    2009-04-01

    MRI-guided transurethral ultrasound therapy is a promising new approach for the treatment of localized prostate cancer. Several studies have demonstrated the feasibility of producing large regions of thermal coagulation adequate for prostate therapy; however, the quantitative assessment of shaping these regions to complex 3-D human prostate geometries has not been fully explored. This study used numerical simulations and twenty manually-segmented pelvic anatomical models derived from high-quality MR images of prostate cancer patients to evaluate the treatment accuracy and safety of 3-D conformal MRI-guided transurethral ultrasound therapy. The simulations incorporated a rotating multi-element planar dual-frequency ultrasound transducer (seventeen 4×3 mm elements) operating at 4.7/9.7 MHz and 10 W/cm2 maximum acoustic power. Results using a novel feedback control algorithm which modulated the ultrasound frequency, power and device rate of rotation showed that regions of thermal coagulation could be shaped to predefined prostate volumes within 1.0 mm across the vast majority of these glands. Treatment times were typically 30 min and remained below 60 min for large 60 cc prostates. With a rectal cooling temperature of 15° C, the rectal wall did not exceed 30EM43 in half of the twenty patient models with only a few 1 mm3 voxels above this threshold in the other cases. At 4.7 MHz, heating of the pelvic bone can become significant when it is located less than 10 mm from the prostate. Numerical simulations show that MRI-guided transurethral ultrasound therapy can thermally coagulate whole prostate glands accurately and safely in 3-D.

  4. Efficacy of XP-endo finisher and TRUShape 3D conforming file compared to conventional and ultrasonic irrigation in removing calcium hydroxide.

    PubMed

    Uygun, Ahmet Demirhan; Gündoğdu, Eyüp Candaş; Arslan, Hakan; Ersoy, İbrahim

    2016-11-12

    The aim of this study was to compare the efficacy of the XP-endo Finisher and TRUShape 3D Conforming File to conventional and ultrasonic irrigation techniques for removing calcium hydroxide from artificially created grooves on root canals. The study used 32 human mandibular premolar teeth, which were decoronated and instrumented up to ProTaper Universal F5 (Dentsply Maillefer; Ballagiues, Switzerland). The teeth were split longitudinally, two standardised grooves were prepared in the apical and coronal portions and filled with calcium hydroxide. Each tooth was reassembled with wax. The samples were stored at 100% humidity at 37°C for 1 week, after which the specimens were grouped and irrigated using needle irrigation, ultrasonic irrigation, XP-endo Finisher via continuous irrigation or TRUShape 3D Conforming File via continuous irrigation. Two calibrated observers scored the amount of calcium hydroxide remaining, and the data were statistically analysed using the Kruskal-Wallis and Mann-Whitney U-tests, (P < 0.05). Needle irrigation had the poorest scores (P < .001), while the XP-endo Finisher, TRUShape 3D Conforming File via continuous irrigation and ultrasonic irrigation groups had similar results in removing calcium hydroxide.

  5. Hepatitis B Virus Reactivation After Three-Dimensional Conformal Radiotherapy in Patients With Hepatitis B Virus-Related Hepatocellular Carcinoma

    SciTech Connect

    Kim, Ji Hoon; Park, Joong-Won Kim, Tae Hyun; Koh, Dong Wook; Lee, Woo Jin; Kim, Chang-Min

    2007-11-01

    Purpose: To investigate whether three-dimensional conformal radiotherapy (3D-CRT) influences hepatitis B virus (HBV) reactivation and chronic hepatitis B (CHB) exacerbation in patients with HBV-related hepatocellular carcinoma (HCC). Methods and Materials: Of the 48 HCC patients with HBV who underwent 3D-CRT to the liver, 16 underwent lamivudine therapy before and during 3D-CRT (Group 1) and 32 did not receive antiviral therapy before 3D-CRT (Group 2). To analyze spontaneous HBV reactivation, we included a control group of 43 HCC patients who did not receive any specific treatment for HCC or CHB. Results: The cumulative rate of radiation-induced liver disease for Groups 1 and 2 was 12.5% (2 of 16) and 21.8% (7 of 32), respectively (p > 0.05). The cumulative rate of HBV reactivation was significantly greater in Group 2 (21.8%, 7 of 32) than in Group 1 (0%, 0/16) or the control group (2.3%, 1 of 43; p < 0.05 each). The cumulative rate of CHB exacerbation, however, did not differ significantly between Groups 2 (12.5%, 4 of 32) and 1 (0%, 0 of 16) or the control group (2.3%, 1 of 43; p > 0.05 each). The CHB exacerbations in the 4 Group 2 patients had radiation-induced liver disease features but were differentiated by serum HBV DNA changes. Two of these patients required antiviral therapy and effectively recovered with lamivudine therapy. Conclusions: In patients with HBV-related HCC undergoing 3D-CRT, HBV reactivation and consequent CHB exacerbation should be considered in the differential diagnosis of radiation-induced liver disease, and antiviral therapy might be considered for the prevention of liver function deterioration after RT.

  6. Acute Toxicity After Image-Guided Intensity Modulated Radiation Therapy Compared to 3D Conformal Radiation Therapy in Prostate Cancer Patients

    SciTech Connect

    Wortel, Ruud C.; Incrocci, Luca; Pos, Floris J.; Lebesque, Joos V.; Witte, Marnix G.; Heide, Uulke A. van der; Herk, Marcel van; Heemsbergen, Wilma D.

    2015-03-15

    Purpose: Image-guided intensity modulated radiation therapy (IG-IMRT) allows significant dose reductions to organs at risk in prostate cancer patients. However, clinical data identifying the benefits of IG-IMRT in daily practice are scarce. The purpose of this study was to compare dose distributions to organs at risk and acute gastrointestinal (GI) and genitourinary (GU) toxicity levels of patients treated to 78 Gy with either IG-IMRT or 3D-CRT. Methods and Materials: Patients treated with 3D-CRT (n=215) and IG-IMRT (n=260) receiving 78 Gy in 39 fractions within 2 randomized trials were selected. Dose surface histograms of anorectum, anal canal, and bladder were calculated. Identical toxicity questionnaires were distributed at baseline, prior to fraction 20 and 30 and at 90 days after treatment. Radiation Therapy Oncology Group (RTOG) grade ≥1, ≥2, and ≥3 endpoints were derived directly from questionnaires. Univariate and multivariate binary logistic regression analyses were applied. Results: The median volumes receiving 5 to 75 Gy were significantly lower (all P<.001) with IG-IMRT for anorectum, anal canal, and bladder. The mean dose to the anorectum was 34.4 Gy versus 47.3 Gy (P<.001), 23.6 Gy versus 44.6 Gy for the anal canal (P<.001), and 33.1 Gy versus 43.2 Gy for the bladder (P<.001). Significantly lower grade ≥2 toxicity was observed for proctitis, stool frequency ≥6/day, and urinary frequency ≥12/day. IG-IMRT resulted in significantly lower overall RTOG grade ≥2 GI toxicity (29% vs 49%, respectively, P=.002) and overall GU grade ≥2 toxicity (38% vs 48%, respectively, P=.009). Conclusions: A clinically meaningful reduction in dose to organs at risk and acute toxicity levels was observed in IG-IMRT patients, as a result of improved technique and tighter margins. Therefore reduced late toxicity levels can be expected as well; additional research is needed to quantify such reductions.

  7. Quality of Life and Survival Outcome for Patients With Nasopharyngeal Carcinoma Receiving Three-Dimensional Conformal Radiotherapy vs. Intensity-Modulated Radiotherapy-A Longitudinal Study

    SciTech Connect

    Fang, F.-M. Chien, C.-Y.; Tsai, W.-L.; Chen, H.-C.; Hsu, H.-C.; Lui, C.-C.; Huang, T.-L.

    2008-10-01

    Purpose: To investigate the changes of quality of life (QoL) and survival outcomes for patients with nasopharyngeal carcinoma (NPC) treated by three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT). Methods and Materials: Two hundred and three newly diagnosed NPC patients, who were curatively treated by 3D-CRT (n = 93) or IMRT (n = 110) between March 2002 and July 2004, were analyzed. The distributions of clinical stage according to American Joint Committee on Cancer 1997 were I: 15 (7.4%), II: 78 (38.4%), III: 74 (36.5%), and IV: 36 (17.7%). QoL was longitudinally assessed by the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and the EORTC QLQ-H and N35 questionnaires at the five time points: before RT, during RT (36 Gy), and 3 months, 12 months, and 24 months after RT. Results: The 3-year locoregional control, metastasis-free survival, and overall survival rates were 84.8%, 76.7%, and 81.7% for the 3D-CRT group, respectively, compared with 84.2%, 82.6%, and 85.4% for the IMRT group (p value > 0.05). A general trend of maximal deterioration in most QoL scales was observed during RT, followed by a gradual recovery thereafter. There was no significant difference in most scales between the two groups at each time point. The exception was that patients treated by IMRT had a both statistically and clinically significant improvement in global QoL, fatigue, taste/smell, dry mouth, and feeling ill at the time point of 3 months after RT. Conclusions: The potential advantage of IMRT over 3D-CRT in treating NPC patients might occur in QoL outcome during the recovery phase of acute toxicity.

  8. Comparison of Heart and Coronary Artery Doses Associated With Intensity-Modulated Radiotherapy Versus Three-Dimensional Conformal Radiotherapy for Distal Esophageal Cancer

    SciTech Connect

    Kole, Thomas P.; Aghayere, Osarhieme; Kwah, Jason; Yorke, Ellen D.; Goodman, Karyn A.

    2012-08-01

    Purpose: To compare heart and coronary artery radiation exposure using intensity-modulated radiotherapy (IMRT) vs. four-field three-dimensional conformal radiotherapy (3D-CRT) treatment plans for patients with distal esophageal cancer undergoing chemoradiation. Methods and Materials: Nineteen patients with distal esophageal cancers treated with IMRT from March 2007 to May 2008 were identified. All patients were treated to 50.4 Gy with five-field IMRT plans. Theoretical 3D-CRT plans with four-field beam arrangements were generated. Dose-volume histograms of the planning target volume, heart, right coronary artery, left coronary artery, and other critical normal tissues were compared between the IMRT and 3D-CRT plans, and selected parameters were statistically evaluated using the Wilcoxon rank-sum test. Results: Intensity-modulated radiotherapy treatment planning showed significant reduction (p < 0.05) in heart dose over 3D-CRT as assessed by average mean dose (22.9 vs. 28.2 Gy) and V30 (24.8% vs. 61.0%). There was also significant sparing of the right coronary artery (average mean dose, 23.8 Gy vs. 35.5 Gy), whereas the left coronary artery showed no significant improvement (mean dose, 11.2 Gy vs. 9.2 Gy), p = 0.11. There was no significant difference in percentage of total lung volume receiving at least 10, 15, or 20 Gy or in the mean lung dose between the planning methods. There were also no significant differences observed for the kidneys, liver, stomach, or spinal cord. Intensity-modulated radiotherapy achieved a significant improvement in target conformity as measured by the conformality index (ratio of total volume receiving 95% of prescription dose to planning target volume receiving 95% of prescription dose), with the mean conformality index reduced from 1.56 to 1.30 using IMRT. Conclusions: Treatment of patients with distal esophageal cancer using IMRT significantly decreases the exposure of the heart and right coronary artery when compared with 3D-CRT

  9. The Effect of Intensity-Modulated Radiotherapy on Radiation-Induced Second Malignancies

    SciTech Connect

    Ruben, Jeremy D. Davis, Sidney; Evans, Cherie; Jones, Phillip; Gagliardi, Frank; Haynes, Matthew; Hunter, Alistair

    2008-04-01

    Purpose: To compare intensity-modulated radiotherapy (IMRT) with three-dimensional conformal radiotherapy (3D-CRT) in terms of carcinogenic risk for actual clinical scenarios. Method and Materials: Clinically equivalent IMRT plans were generated for prostate, breast, and head-and-neck cases treated with 3D-CRT. Two possible dose-response models for radiocarcinogenesis were generated based on A-bomb survivor data corrected for fractionation. Dose-volume histogram analysis was used to determine dose and its distribution to nontargeted tissues within the planning CT scan volume and thermoluminescent dosimetry for the rest of the body. Carcinogenic estimates were calculated with and without a correction factor accounting for cancer patients' advanced age and reduced longevity. Results: For the model assuming a plateau in risk above 2-Gy single-fraction-equivalent (SFE), IMRT and 3D-CRT produced risks of 1.7% and 2.1%, respectively, for prostate; 1.9% and 1.8%, respectively, for nasopharynx; 1% each for tonsil; and 1.4-2.2% and 1.5-1.6%, respectively, depending on technique, for breast. Assuming a reduction in risk above 2-Gy SFE, risks for IMRT and 3D-CRT were 1.1% and 1.5%, respectively, for prostate; 1.4% and 1.2%, respectively, for nasopharynx; 1% each for tonsil; and 1.3-1.8% vs. 1.3-1.6%, respectively, for breast. Applying a correction factor of 0.5 for cancer patients halved these risks and their relative differences. Conclusions: Carcinogenic risks were comparable in absolute terms between modalities. Risks are dependant on technique used. Risks with IMRT are influenced by monitor unit demand and are therefore software/hardware dependant. The dose-response model accounting for cell killing at higher doses fitted best with actual observed risks.

  10. Equivalent Biochemical Control and Improved Prostate-Specific Antigen Nadir After Permanent Prostate Seed Implant Brachytherapy Versus High-Dose Three-Dimensional Conformal Radiotherapy and High-Dose Conformal Proton Beam Radiotherapy Boost

    SciTech Connect

    Jabbari, Siavash; Weinberg, Vivian K.; Shinohara, Katsuto; Speight, Joycelyn L.; Gottschalk, Alexander R.; Hsu, I.-C.; Pickett, Barby; McLaughlin, Patrick W.; Sandler, Howard M.; Roach, Mack

    2010-01-15

    Purpose: Permanent prostate implant brachytherapy (PPI), three-dimensional conformal radiotherapy (3D-CRT), and conformal proton beam radiotherapy (CPBRT) are used in the treatment of localized prostate cancer, although no head-to-head trials have compared these modalities. We studied the biochemical control (biochemical no evidence of disease [bNED]) and prostate-specific antigen (PSA) nadir achieved with contemporary PPI, and evaluated it against 3D-CRT and CPBRT. Patients and Methods: A total of 249 patients were treated with PPI at the University of California, San Francisco, and the outcomes were compared with those from a 3D-CRT cohort and the published results of a high-dose CPBRT boost (CPBRTB) trial. For each comparison, subsets of the PPI cohort were selected with patient and disease criteria similar to those of the reference group. Results: With a median follow-up of 5.3 years, the bNED rate at 5 and 7 years achieved with PPI was 92% and 86%, respectively, using the American Society for Therapeutic Radiology and Oncology (ASTRO) definition, and 93% using the PSA nadir plus 2 ng/mL definition. Using the ASTRO definition, a 5-year bNED rate of 78% was achieved for the 3D-CRT patients compared with 94% for a comparable PPI subset and 93% vs. 92%, respectively, using the PSA nadir plus 2 ng/mL definition. The median PSA nadir for patients treated with PPI and 3D-CRT was 0.10 and 0.40 ng/mL, respectively (p < .0001). For the CPBRT comparison, the 5-year bNED rate after a CPBRTB was 91% using the ASTRO definition vs. 93% for a similar group of PPI patients. A greater proportion of PPI patients achieved a lower PSA nadir compared with those achieved in the CPBRTB trial (PSA nadir <=0.5 ng/mL, 91% vs. 59%, respectively). Conclusion: We have demonstrated excellent outcomes in low- to intermediate-risk patients treated with PPI, suggesting at least equivalent 5-year bNED rates and a greater proportion of men achieving lower PSA nadirs compared with 3D-CRT or

  11. Image-Guided Radiotherapy and -Brachytherapy for Cervical Cancer

    PubMed Central

    Dutta, Suresh; Nguyen, Nam Phong; Vock, Jacqueline; Kerr, Christine; Godinez, Juan; Bose, Satya; Jang, Siyoung; Chi, Alexander; Almeida, Fabio; Woods, William; Desai, Anand; David, Rick; Karlsson, Ulf Lennart; Altdorfer, Gabor

    2015-01-01

    Conventional radiotherapy for cervical cancer relies on clinical examination, 3-dimensional conformal radiotherapy (3D-CRT), and 2-dimensional intracavitary brachytherapy. Excellent local control and survival have been obtained for small early stage cervical cancer with definitive radiotherapy. For bulky and locally advanced disease, the addition of chemotherapy has improved the prognosis but toxicity remains significant. New imaging technology such as positron-emission tomography and magnetic resonance imaging has improved tumor delineation for radiotherapy planning. Image-guided radiotherapy (IGRT) may decrease treatment toxicity of whole pelvic radiation because of its potential for bone marrow, bowel, and bladder sparring. Tumor shrinkage during whole pelvic IGRT may optimize image-guided brachytherapy (IGBT), allowing for better local control and reduced toxicity for patients with cervical cancer. IGRT and IGBT should be integrated in future prospective studies for cervical cancer. PMID:25853092

  12. Image-guided radiotherapy and -brachytherapy for cervical cancer.

    PubMed

    Dutta, Suresh; Nguyen, Nam Phong; Vock, Jacqueline; Kerr, Christine; Godinez, Juan; Bose, Satya; Jang, Siyoung; Chi, Alexander; Almeida, Fabio; Woods, William; Desai, Anand; David, Rick; Karlsson, Ulf Lennart; Altdorfer, Gabor

    2015-01-01

    Conventional radiotherapy for cervical cancer relies on clinical examination, 3-dimensional conformal radiotherapy (3D-CRT), and 2-dimensional intracavitary brachytherapy. Excellent local control and survival have been obtained for small early stage cervical cancer with definitive radiotherapy. For bulky and locally advanced disease, the addition of chemotherapy has improved the prognosis but toxicity remains significant. New imaging technology such as positron-emission tomography and magnetic resonance imaging has improved tumor delineation for radiotherapy planning. Image-guided radiotherapy (IGRT) may decrease treatment toxicity of whole pelvic radiation because of its potential for bone marrow, bowel, and bladder sparring. Tumor shrinkage during whole pelvic IGRT may optimize image-guided brachytherapy (IGBT), allowing for better local control and reduced toxicity for patients with cervical cancer. IGRT and IGBT should be integrated in future prospective studies for cervical cancer.

  13. Functional outcome of patients with benign meningioma treated by 3D conformal irradiation with a combination of photons and protons

    SciTech Connect

    Noel, Georges . E-mail: noel@ipno.in2p3.fr; Bollet, Marc A.; Calugaru, Valentin; Feuvret, Loic; Haie-Meder, Christine; Dhermain, Frederic; Ferrand, Regis; Boisserie, Gilbert; Beaudre, Anne; Mazeron, Jean-Jacques; Habrand, Jean-Louis

    2005-08-01

    Purpose: To evaluate efficacy and tolerance of external fractionated combination of photon and proton radiation therapy (RT) for intracranial benign meningiomas. Methods and Materials: Between 1994 and 2002, 51 patients with intracranial meningiomas of the base of the skull were treated with a combination of photon and proton RT. Median total dose was 60.6 cobalt Gy equivalent (54-64). One hundred eight eye-related symptoms were collected; 80 other symptoms were noted and followed up. Results: Mean follow-up was 25.4 months. Acute tolerance was excellent. Out of the 108 eye-related symptoms, 106 (96%) were evaluated. Improvements were reported for 73 (68.8%) of them. Out of the 88 other miscellaneous symptoms, 81 (92%) were evaluated. Improvements were reported in 54 cases (67%). Median time to improvement ranged from 1 to 24 months after completion of the radiotherapy, depending on the symptom. We did not observe any worsening of primary clinical signs. Radiologically, 1 patient relapsed 4 months after the end of irradiation. Pathology revealed a malignant (Grade 3) transformation of the initial Grade 1 meningioma. Four-year local control and overall survival rates were, respectively, 98% and 100%. Stabilization of the tumor was observed in 38 cases (72%), volume reduction in 10 cases (20%), and intratumor necrosis in 3 cases. Two patients complained of Grade 3 side effects: 1 unilateral hearing loss requiring aid and 1 case of complete pituitary deficiency. Conclusion: These results stressed the clinical efficacy of fractionated-associated photon-proton RT in the treatment of meningiomas, especially on cranial nerve palsies, without severe toxicity in almost all patients.

  14. Phase II Study of Vinorelbine and Estramustine in Combination With Conformational Radiotherapy for Patients With High-Risk Prostate Cancer

    SciTech Connect

    Carles, Joan; Nogue, Miguel; Sole, Josep M.; Foro, Palmira; Domenech, Montserrat; Suarez, Marta; Gallardo, Enrique; Garcia, Dario; Ferrer, Ferran; Gelabert-Mas, Antoni; Gayo, Javier; Fabregat, Xavier

    2010-03-15

    Purpose: To evaluate the efficacy and safety profile of vinorelbine and estramustine in combination with three-dimensional conformational radiotherapy (3D-CRT) in patients with localized high-risk prostate cancer. Methods and Materials: Fifty patients received estramustine, 600 mg/m{sup 2} daily, and vinorelbine, 25 mg/m{sup 2}, on days 1 and 8 of a 21-day cycle for three cycles in combination with 8 weeks of 3D-CRT (total dose of 70.2 gray [Gy] at 1.8-Gy fractions or 70 Gy at 2.0-Gy fractions). Additionally, patients received luteinizing hormone-releasing hormone analogs for 3 years. Results: All patients were evaluated for response and toxicity. Progression-free survival at 5 years was 72% (95% confidence interval [CI]: 52-86). All patients who relapsed had only biochemical relapse. The most frequent severe toxicities were cystitis (16% of patients), leucopenia (10% of patients), diarrhea (10% of patients), neutropenia (8% of patients), and proctitis (8% of patients). Six patients (12%) did not complete study treatment due to the patient's decision (n = 1) and to adverse events such as hepatotoxicity, proctitis, paralytic ileus, and acute myocardial infarction. Conclusions: Vinorelbine and estramustine in combination with 3D-CRT is a safe and effective regimen for patients with localized high-risk prostate cancer. A randomized trial is needed to determine whether the results of this regimen are an improvement over the results obtained with radiotherapy and androgen ablation.

  15. Volumetric-modulated arc radiotherapy for pancreatic malignancies: Dosimetric comparison with sliding-window intensity-modulated radiotherapy and 3-dimensional conformal radiotherapy

    SciTech Connect

    Nabavizadeh, Nima Simeonova, Anna O.; Waller, Joseph G.; Romer, Jeanna L.; Monaco, Debra L.; Elliott, David A.; Tanyi, James A.; Fuss, Martin; Thomas, Charles R.; Holland, John M.

    2014-10-01

    Volumetric-modulated arc radiotherapy (VMAT) is an iteration of intensity-modulated radiotherapy (IMRT), both of which deliver highly conformal dose distributions. Studies have shown the superiority of VMAT and IMRT in comparison with 3-dimensional conformal radiotherapy (3D-CRT) in planning target volume (PTV) coverage and organs-at-risk (OARs) sparing. This is the first study examining the benefits of VMAT in pancreatic cancer for doses more than 55.8 Gy. A planning study comparing 3D-CRT, IMRT, and VMAT was performed in 20 patients with pancreatic cancer. Treatments were planned for a 25-fraction delivery of 45 Gy to a large field followed by a reduced-volume 8-fraction external beam boost to 59.4 Gy in total. OARs and PTV doses, conformality index (CI) deviations from 1.0, monitor units (MUs) delivered, and isodose volumes were compared. IMRT and VMAT CI deviations from 1.0 for the large-field and the boost plans were equivalent (large field: 0.032 and 0.046, respectively; boost: 0.042 and 0.037, respectively; p > 0.05 for all comparisons). Both IMRT and VMAT CI deviations from 1.0 were statistically superior to 3D-CRT (large field: 0.217, boost: 0.177; p < 0.05 for all comparisons). VMAT showed reduction of the mean dose to the boost PTV (VMAT: 61.4 Gy, IMRT: 62.4 Gy, and 3D-CRT: 62.3 Gy; p < 0.05). The mean number of MUs per fraction was significantly lower for VMAT for both the large-field and the boost plans. VMAT delivery time was less than 3 minutes compared with 8 minutes for IMRT. Although no statistically significant dose reduction to the OARs was identified when comparing VMAT with IMRT, VMAT showed a reduction in the volumes of the 100% isodose line for the large-field plans. Dose escalation to 59.4 Gy in pancreatic cancer is dosimetrically feasible with shorter treatment times, fewer MUs delivered, and comparable CIs for VMAT when compared with IMRT.

  16. Dosimetric comparison of intensity modulated radiotherapy isocentric field plans and field in field (FIF) forward plans in the treatment of breast cancer.

    PubMed

    Al-Rahbi, Zakiya Salem; Al Mandhari, Zahid; Ravichandran, Ramamoorthy; Al-Kindi, Fatma; Davis, Cheriyathmanjiyil Anthony; Bhasi, Saju; Satyapal, Namrata; Rajan, Balakrishnan

    2013-01-01

    The present study is aimed at comparing the planning and delivery efficiency between three-dimensional conformal radiotherapy (3D-CRT), field-in-field, forward planned, intensity modulated radiotherapy (FIF-FP-IMRT), and inverse planned intensity modulated radiotherapy (IP-IMRT). Treatment plans of 20 patients with left-sided breast cancer, 10 post-mastectomy treated to a prescribed dose of 45 Gy to the chest wall in 20 fractions, and 10 post-breast-conserving surgery to a prescribed dose of 50 Gy to the whole breast in 25 fractions, with 3D-CRT were selected. The FiF-FP-IMRT plans were created by combining two open fields with three to four segments in two tangential beam directions. Eight different beam directions were chosen to create IP-IMRT plans and were inversely optimized. The homogeneity of dose to planning target volume (PTV) and the dose delivered to heart and contralateral breast were compared among the techniques in all the 20 patients. All the three radiotherapy techniques achieved comparable radiation dose delivery to PTV-95% of the prescribed dose covering > 95% of the breast PTV. The mean volume of PTV receiving 105% (V105) of the prescribed dose was 1.7% (range 0-6.8%) for IP-IMRT, 1.9% for FP-IMRT, and 3.7% for 3D-CRT. The homogeneity and conformity indices (HI and CI) were similar for 3D-CRT and FP-IMRT, whereas the IP-IMRT plans had better conformity index at the cost of less homogeneity. The 3D-CRT and FiF-FP-IMRT plans achieved similar sparing of critical organs. The low-dose volumes (V5Gy) in the heart and lungs were larger in IP-IMRT than in the other techniques. The value of the mean dose to the ipsilateral lung was higher for IP-IMRT than the values for with FiF-FP-IMRT and 3D-CRT. In the current study, the relative volume of contralateral breast receiving low doses (0.01, 0.6, 1, and 2Gy) was significantly lower for the FiF-FP-IMRT and 3D-CRT plans than for the IP-IMRT plan. Compared with 3D-CRT and IP-IMRT, FiF-FP-IMRT proved to be a

  17. Dosimetric comparison of intensity modulated radiotherapy isocentric field plans and field in field (FIF) forward plans in the treatment of breast cancer

    PubMed Central

    Al-Rahbi, Zakiya Salem; Al Mandhari, Zahid; Ravichandran, Ramamoorthy; Al-Kindi, Fatma; Davis, Cheriyathmanjiyil Anthony; Bhasi, Saju; Satyapal, Namrata; Rajan, Balakrishnan

    2013-01-01

    The present study is aimed at comparing the planning and delivery efficiency between three-dimensional conformal radiotherapy (3D-CRT), field-in-field, forward planned, intensity modulated radiotherapy (FIF-FP-IMRT), and inverse planned intensity modulated radiotherapy (IP-IMRT). Treatment plans of 20 patients with left-sided breast cancer, 10 post-mastectomy treated to a prescribed dose of 45 Gy to the chest wall in 20 fractions, and 10 post-breast-conserving surgery to a prescribed dose of 50 Gy to the whole breast in 25 fractions, with 3D-CRT were selected. The FiF-FP-IMRT plans were created by combining two open fields with three to four segments in two tangential beam directions. Eight different beam directions were chosen to create IP-IMRT plans and were inversely optimized. The homogeneity of dose to planning target volume (PTV) and the dose delivered to heart and contralateral breast were compared among the techniques in all the 20 patients. All the three radiotherapy techniques achieved comparable radiation dose delivery to PTV-95% of the prescribed dose covering > 95% of the breast PTV. The mean volume of PTV receiving 105% (V105) of the prescribed dose was 1.7% (range 0-6.8%) for IP-IMRT, 1.9% for FP-IMRT, and 3.7% for 3D-CRT. The homogeneity and conformity indices (HI and CI) were similar for 3D-CRT and FP-IMRT, whereas the IP-IMRT plans had better conformity index at the cost of less homogeneity. The 3D-CRT and FiF-FP-IMRT plans achieved similar sparing of critical organs. The low-dose volumes (V5Gy) in the heart and lungs were larger in IP-IMRT than in the other techniques. The value of the mean dose to the ipsilateral lung was higher for IP-IMRT than the values for with FiF-FP-IMRT and 3D-CRT. In the current study, the relative volume of contralateral breast receiving low doses (0.01, 0.6, 1, and 2Gy) was significantly lower for the FiF-FP-IMRT and 3D-CRT plans than for the IP-IMRT plan. Compared with 3D-CRT and IP-IMRT, FiF-FP-IMRT proved to be a

  18. Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer*

    PubMed Central

    Poli, Ana Paula Diniz Fortuna; Dias, Rodrigo Souza; Giordani, Adelmo José; Segreto, Helena Regina Comodo; Segreto, Roberto Araujo

    2016-01-01

    Objective To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Materials and Methods Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined. The prostate contour was compared with the initial CT images considering the anterior, posterior, superior, inferior and lateral edges of the organ. Variations in the anterior limits and volume of the rectum were assessed and correlated with prostate motion in the anteroposterior direction. Results The maximum range of prostate motion was observed in the superoinferior direction, followed by the anteroposterior direction. A significant correlation was observed between prostate motion and rectal volume variation (p = 0.037). A baseline rectal volume superior to 70 cm3 had a significant influence on the prostate motion in the anteroposterior direction (p = 0.045). Conclusion The present study showed a significant interfraction motion of the prostate during 3D-CRT with greatest variations in the superoinferior and anteroposterior directions, and that a large rectal volume influences the prostate motion with a cutoff value of 70 cm3. Therefore, the treatment of patients with a rectal volume > 70 cm3 should be re-planned with appropriate rectal preparation. PMID:26929456

  19. Dosimetric study of volumetric arc modulation with RapidArc and intensity-modulated radiotherapy in patients with cervical cancer and comparison with 3-dimensional conformal technique for definitive radiotherapy in patients with cervical cancer

    SciTech Connect

    Guy, Jean-Baptiste; Falk, Alexander T.; Auberdiac, Pierre; Cartier, Lysian; Vallard, Alexis; Ollier, Edouard; Trone, Jane-Chloé; Khodri, Moustapha; Chargari, Cyrus; Magné, Nicolas

    2016-04-01

    Introduction: For patients with cervical cancer, intensity-modulated radiation therapy (IMRT) improves target coverage and allows dose escalation while reducing the radiation dose to organs at risk (OARs). In this study, we compared dosimetric parameters among 3-dimensional conformal radiotherapy (3D-CRT), “step-and-shoot” IMRT, and volumetric intensity-modulated arc radiotherapy (VMAT) in a series of patients with cervical cancer receiving definitive radiotherapy. Computed tomography (CT) scans of 10 patients with histologically proven cervical cancer treated with definitive radiation therapy (RT) from December 2008 to March 2010 at our department were selected for this study. The gross tumor volume (GTV) and clinical target volume (CTV) were delineated following the guidelines of the Gyn IMRT consortium that included cervix, uterus, parametrial tissues, and the pelvic nodes including presacral. The median age was 57 years (range: 30 to 85 years). All 10 patients had squamous cell carcinoma with Federation of Gynecology and Obstetrics (FIGO) stage IB-IIIB. All patients were treated by VMAT. OAR doses were significantly reduced for plans with intensity-modulated technique compared with 3D-CRT except for the dose to the vagina. Between the 2 intensity-modulated techniques, significant difference was observed for the mean dose to the small intestine, to the benefit of VMAT (p < 0.001). There was no improvement in terms of OARs sparing for VMAT although there was a tendency for a slightly decreased average dose to the rectum: − 0.65 Gy but not significant (p = 0.07). The intensity modulation techniques have many advantages in terms of quality indexes, and particularly OAR sparing, compared with 3D-CRT. Following the ongoing technologic developments in modern radiotherapy, it is essential to evaluate the intensity-modulated techniques on prospective studies of a larger scale.

  20. High-dose-rate Three-dimensional Conformal Radiotherapy Combined with Active Breathing Control for Stereotactic Body Radiotherapy of Early-stage Non-small-cell Lung Cancer.

    PubMed

    Wang, Ruozheng; Yin, Yong; Qin, Yonghui; Yu, Jinming

    2015-12-01

    The purpose of this study was to evaluate the feasibility and benefits of using high-dose-rate three-dimensional conformal radiotherapy (3D-CRT) combined with active breathing control (ABC) for stereotactic body radiotherapy (SBRT) of patients with early-stage non-small-cell lung cancer (NSCLC). Eight patients with early-stage NSCLC underwent CT scans under standard free-breathing (FB) and moderately deep inspiration breath-hold (mDIBH) with ABC. Two high-dose-rate 3D-CRT plans (1000 Mu/min) were designed based on the CT scans with FB and mDIBH. The maximal dose (D1%), minimal dose (D99%), conformity index (CI), and homogeneity index (HI) of the planning target volume (PTV), and dose-volume indices of the organs at risk between each plan were compared. The mean PTV volume decreased from 158.04 cm(3) with FB to 76.90 cm(3) with mDIBH (p < 0.05). When mDIBH was used, increases in the affected lung volume (by 47%), contralateral lung volume (by 55%), and total lung volume (by 50%) were observed compared to FB (p < 0.05). The V5-V40 of the affected lung (Vx represented the percentage volume of organs receiving at least the x Gy), V5-V40 and the mean dose for the total lung, V5-V40 and mean dose of the chest wall, and the maximum dose of the spinal cord were less for mDIBH than FB (p < 0.05). There were no significant differences in CI, HI, D1%, or D99% for the PTV between the plans. In conclusion, high-dose-rate 3D-CRT combined with ABC reduced the radiation dose to the lungs and chest wall without affecting the dose distribution in SBRT of early-stage NSCLC patients.

  1. SU-C-BRE-01: 3D Conformal Micro Irradiation Results of Four Treatment Sites for Preclinical Small Animal and Clinical Treatment Plans

    SciTech Connect

    Price, S; Yaddanapudi, S; Rangaraj, D; Izaguirre, E

    2014-06-15

    Purpose: Small animal irradiation can provide preclinical insights necessary for clinical advancement. In order to provide clinically relevant data, these small animal irradiations must be designed such that the treatment methods and results are comparable to clinical protocols, regardless of variations in treatment size and modality. Methods: Small animal treatments for four treatment sites (brain, liver, lung and spine) were investigated, accounting for change in treatment energy and target size. Up to five orthovoltage (300kVp) beams were used in the preclinical treatments, using circular, square, and conformal tungsten apertures, based on the treatment site. Treatments were delivered using the image guided micro irradiator (microIGRT). The plans were delivered to a mouse sized phantom and dose measurements in axial and coronal planes were performed using radiochromic film. The results of the clinical and preclinical protocols were characterized in terms of conformality number, CTV coverage, dose nonuniformity ratio, and organ at risk sparing. Results: Preclinical small animal treatment conformality was within 1–16% of clinical results for all treatment sites. The volume of the CTV receiving 100% of the prescription dose was typically within 10% of clinical values. The dose non-uniformity was consistently higher for preclinical treatments compared to clinical treatments, indicating hot spots in the target. The ratios of the mean dose in the target to the mean dose in an organ at risk were comparable if not better for preclinical versus clinical treatments. Finally, QUANTEC dose constraints were applied and the recommended morbidity limits were satisfied in each small animal treatment site. Conclusion: We have shown that for four treatment sites, preclinical 3D conformal small animal treatments can be clinically comparable if clinical protocols are followed. Using clinical protocols as the standard, preclinical irradiation methods can be altered and iteratively

  2. Cost-Effectiveness Analysis of Stereotactic Body Radiotherapy and Radiofrequency Ablation for Medically Inoperable, Early-Stage Non-Small Cell Lung Cancer

    SciTech Connect

    Sher, David J.

    2011-12-01

    Purpose: The standard management of medically inoperable Stage I non-small-cell lung cancer (NSCLC) conventionally has been fractionated three-dimensional conformal radiation therapy (3D-CRT). The relatively poor local control rate and inconvenience associated with this therapy have prompted the development of stereotactic body radiotherapy (SBRT), a technique that delivers very high doses of irradiation typically over 3 to 5 sessions. Radiofrequency ablation (RFA) has also been investigated as a less costly, single-day therapy that thermally ablates small, peripheral tumors. The cost-effectiveness of these three techniques has never been compared. Methods and Materials: We developed a Markov model to describe health states of 65-year-old men with medically inoperable NSCLC after treatment with 3D-CRT, SBRT, and RFA. Given their frail state, patients were assumed to receive supportive care after recurrence. Utility values, recurrence risks, and costs were adapted from the literature. Sensitivity analyses were performed to model uncertainty in these parameters. Results: The incremental cost-effectiveness ratio for SBRT over 3D-CRT was $6,000/quality-adjusted life-year, and the incremental cost-effectiveness ratio for SBRT over RFA was $14,100/quality-adjusted life-year. One-way sensitivity analysis showed that the results were robust across a range of tumor sizes, patient utility values, and costs. This result was confirmed with probabilistic sensitivity analyses that varied local control rates and utilities. Conclusion: In comparison to 3D-CRT and RFA, SBRT was the most cost-effective treatment for medically inoperable NSCLC over a wide range of treatment and disease assumptions. On the basis of efficacy and cost, SBRT should be the primary treatment approach for this disease.

  3. Radiological and Clinical Pneumonitis After Stereotactic Lung Radiotherapy: A Matched Analysis of Three-Dimensional Conformal and Volumetric-modulated Arc Therapy Techniques

    SciTech Connect

    Palma, David A.; Senan, Suresh; Haasbeek, Cornelis J.A.; Verbakel, Wilko F.A.R.; Vincent, Andrew; Lagerwaard, Frank

    2011-06-01

    Purpose: Lung fibrosis is common after stereotactic body radiotherapy (SBRT) for lung tumors, but the influence of treatment technique on rates of clinical and radiological pneumonitis is not well described. After implementing volumetric modulated arc therapy (RapidArc [RA]; Varian Medical Systems, Palo Alto, CA) for SBRT, we scored the early pulmonary changes seen with arc and conventional three-dimensional SBRT (3D-CRT). Methods and Materials: Twenty-five SBRT patients treated with RA were matched 1:2 with 50 SBRT patients treated with 3D-CRT. Dose fractionations were based on a risk-adapted strategy. Clinical pneumonitis was scored using Common Terminology Criteria for Adverse Events version 3.0. Acute radiological changes 3 months posttreatment were scored by three blinded observers. Relationships among treatment type, baseline factors, and outcomes were assessed using Spearman's correlation, Cochran-Mantel-Haenszel tests, and logistic regression. Results: The RA and 3D-CRT groups were well matched. Forty-three patients (57%) had radiological pneumonitis 3 months after treatment. Twenty-eight patients (37%) had computed tomography (CT) findings of patchy or diffuse consolidation, and 15 patients (20%) had ground-glass opacities only. Clinical pneumonitis was uncommon, and no differences were seen between 3D-CRT vs. RA patients in rates of grade 2/3 clinical pneumonitis (6% vs. 4%, respectively; p = 0.99), moderate/severe radiological changes (24% vs. 36%, respectively, p = 0.28), or patterns of CT changes (p = 0.47). Radiological severity scores were associated with larger planning target volumes (p = 0.09) and extended fractionation (p = 0.03). Conclusions: Radiological changes after lung SBRT are common with both approaches, but no differences in early clinical or radiological findings were observed after RA. Longer follow-up will be required to exclude late changes.

  4. A Dosimetric Comparison of Accelerated Partial Breast Irradiation Techniques: Multicatheter Interstitial Brachytherapy, Three-Dimensional Conformal Radiotherapy, and Supine Versus Prone Helical Tomotherapy

    SciTech Connect

    Patel, Rakesh R. . E-mail: patel@humonc.wisc.edu; Becker, Stewart J.; Das, Rupak K.; Mackie, Thomas R.

    2007-07-01

    Purpose: To compare dosimetrically four different techniques of accelerated partial breast irradiation (APBI) in the same patient. Methods and Materials: Thirteen post-lumpectomy interstitial brachytherapy (IB) patients underwent imaging with preimplant computed tomography (CT) in the prone and supine position. These CT scans were then used to generate three-dimensional conformal radiotherapy (3D-CRT) and prone and supine helical tomotherapy (PT and ST, respectively) APBI plans and compared with the treated IB plans. Dose-volume histogram analysis and the mean dose (NTD{sub mean}) values were compared. Results: Planning target volume coverage was excellent for all methods. Statistical significance was considered to be a p value <0.05. The mean V100 was significantly lower for IB (12% vs. 15% for PT, 18% for ST, and 26% for 3D-CRT). A greater significant differential was seen when comparing V50 with mean values of 24%, 43%, 47%, and 52% for IB, PT, ST, and 3D-CRT, respectively. The IB and PT were similar and delivered an average lung NTD{sub mean} dose of 1.3 Gy{sub 3} and 1.2 Gy{sub 3}, respectively. Both of these methods were statistically significantly lower than the supine external beam techniques. Overall, all four methods yielded similar low doses to the heart. Conclusions: The use of IB and PT resulted in greater normal tissue sparing (especially ipsilateral breast and lung) than the use of supine external beam techniques of 3D-CRT or ST. However, the choice of APBI technique must be tailored to the patient's anatomy, lumpectomy cavity location, and overall treatment goals.

  5. Postoperative Intensity Modulated Radiation Therapy in High Risk Prostate Cancer: A Dosimetric Comparison

    SciTech Connect

    Digesu, Cinzia; Cilla, Savino; De Gaetano, Andrea; Massaccesi, Mariangela; Macchia, Gabriella; Ippolito, Edy; Deodato, Francesco; Panunzi, Simona; Iapalucci, Chiara; Mattiucci, Gian Carlo; D'Angelo, Elisa; Padula, Gilbert D.A.; Valentini, Vincenzo; Cellini, Numa

    2011-10-01

    The aim of this study was to compare intensity-modulated radiation therapy (IMRT) with 3D conformal technique (3D-CRT), with respect to target coverage and irradiation of organs at risk for high dose postoperative radiotherapy (PORT) of the prostate fossa. 3D-CRT and IMRT treatment plans were compared with respect to dose to the rectum and bladder. The dosimetric comparison was carried out in 15 patients considering 2 different scenarios: (1) exclusive prostate fossa irradiation, and (2) pelvic node irradiation followed by a boost on the prostate fossa. In scenario (1), a 3D-CRT plan (box technique) and an IMRT plan were calculated and compared for each patient. In scenario (2), 3 treatment plans were calculated and compared for each patient: (a) 3D-CRT box technique for both pelvic (prophylactic nodal irradiation) and prostate fossa irradiation (3D-CRT only); (b) 3D-CRT box technique for pelvic irradiation followed by an IMRT boost to the prostatic fossa (hybrid 3D-CRT and IMRT); and (c) IMRT for both pelvic and prostate fossa irradiation (IMRT only). For exclusive prostate fossa irradiation, IMRT significantly reduced the dose to the rectum (lower Dmean, V50%, V75%, V90%, V100%, EUD, and NTCP) and the bladder (lower Dmean, V50%, V90%, EUD and NTCP). When prophylactic irradiation of the pelvis was also considered, plan C (IMRT only) performed better than plan B (hybrid 3D-CRT and IMRT) as respect to both rectum and bladder irradiation (reduction of Dmean, V50%, V75%, V90%, equivalent uniform dose [EUD], and normal tissue complication probability [NTCP]). Plan (b) (hybrid 3D-CRT and IMRT) performed better than plan (a) (3D-CRT only) with respect to dose to the rectum (lower Dmean, V75%, V90%, V100%, EUD, and NTCP) and the bladder (Dmean, EUD, and NTCP). Postoperative IMRT in prostate cancer significantly reduces rectum and bladder irradiation compared with 3D-CRT.

  6. Can All Centers Plan Intensity-Modulated Radiotherapy (IMRT) Effectively? An External Audit of Dosimetric Comparisons Between Three-Dimensional Conformal Radiotherapy and IMRT for Adjuvant Chemoradiation for Gastric Cancer

    SciTech Connect

    Chung, Hans T. Lee, Brian; Park, Eileen; Lu, Jiade J.; Xia Ping

    2008-07-15

    Purpose: To compare dosimetric endpoints between three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) at our center with limited IMRT experience, and to perform an external audit of the IMRT plans. Methods and Materials: Ten patients, who received adjuvant chemoradiation for gastric cancer, formed the study cohort. For standardization, the planning target volume (PTV) and organs at risk were recontoured with the assistance of a study protocol radiologic atlas. The cohort was replanned with CMS Xio to generate coplanar 3D-CRT and IMRT plans. All 10 datasets, including volumes but without the plans (i.e., blinded), were transmitted to an experienced center where IMRT plans were designed using Nomos Corvus (IMRT-C) and ADAC Pinnacle (IMRT-P). All IMRT plans were normalized to D95% receiving 45 Gy. Results: Intensity-modulated radiotherapy yielded higher PTV V45 (volume that receives {>=}45 Gy) (p < 0.001) than 3D-CRT. No difference in V20 was seen in the right (p = 0.9) and left (p 0.3) kidneys, but the liver mean dose (p < 0.001) was superior with IMRT. For the external audit, IMRT-C (p = 0.002) and IMRT-P (p < 0.001) achieved significantly lower left kidney V20 than IMRT, and IMRT-P (p < 0.001) achieved lower right kidney V20 than IMRT. The IMRT-C (p = 0.003) but not IMRT-P (p = 0.6) had lower liver mean doses than IMRT. Conclusions: At our institution with early IMRT experience, IMRT improved PTV dose coverage and liver doses but not kidney doses. An external audit of IMRT plans showed that an experienced center can yield superior IMRT plans.

  7. Dosimetric comparison of axilla and groin radiotherapy techniques for high-risk and locally advanced skin cancer

    PubMed Central

    Mattes, Malcolm D.; Zhou, Ying; Berry, Sean L.; Barker, Christopher A.

    2016-01-01

    Purpose: Radiation therapy targeting axilla and groin lymph nodes improves regional disease control in locally advanced and high-risk skin cancers. However, trials generally used conventional two-dimensional radiotherapy (2D-RT), contributing towards relatively high rates of side effects from treatment. The goal of this study is to determine if three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), or volumetric-modulated arc therapy (VMAT) may improve radiation delivery to the target while avoiding organs at risk in the clinical context of skin cancer regional nodal irradiation. Materials and Methods: Twenty patients with locally advanced/high-risk skin cancers underwent computed tomography simulation. The relevant axilla or groin planning target volumes and organs at risk were delineated using standard definitions. Paired t-tests were used to compare the mean values of several dose-volumetric parameters for each of the 4 techniques. Results: In the axilla, the largest improvement for 3D-CRT compared to 2D-RT was for homogeneity index (13.9 vs. 54.3), at the expense of higher lung V20 (28.0% vs. 12.6%). In the groin, the largest improvements for 3D-CRT compared to 2D-RT were for anorectum Dmax (13.6 vs. 38.9 Gy), bowel D200cc (7.3 vs. 23.1 Gy), femur D50 (34.6 vs. 57.2 Gy), and genitalia Dmax (37.6 vs. 51.1 Gy). IMRT had further improvements compared to 3D-CRT for humerus Dmean (16.9 vs. 22.4 Gy), brachial plexus D5 (57.4 vs. 61.3 Gy), bladder D5 (26.8 vs. 36.5 Gy), and femur D50 (18.7 vs. 34.6 Gy). Fewer differences were observed between IMRT and VMAT. Conclusion: Compared to 2D-RT and 3D-CRT, IMRT and VMAT had dosimetric advantages in the treatment of nodal regions of skin cancer patients. PMID:27306779

  8. Comparison of Radiation Treatment Plans for Breast Cancer between 3D Conformal in Prone and Supine Positions in Contrast to VMAT and IMRT Supine Positions

    NASA Astrophysics Data System (ADS)

    Bejarano Buele, Ana Isabel

    The treatment regimen for breast cancer patients typically involves Whole Breast Irradiation (WBI). The coverage and extent of the radiation treatment is dictated by location of tumor mass, breast tissue distribution, involvement of lymph nodes, and other factors. The current standard treatment approach used at our institution is a 3D tangential beam geometry, which involves two fields irradiating the breast, or a four field beam arrangement covering the whole breast and involved nodes, while decreasing the dose to organs as risk (OARs) such as the lung and heart. The coverage of these targets can be difficult to achieve in patients with unfavorable thoracic geometries, especially in those cases in which the planning target volume (PTV) is extended to the chest wall. It is a well-known fact that exposure of the heart to ionizing radiation has been proved to increase the subsequent rate of ischemic heart disease. In these cases, inverse planned treatments have become a proven alternative to the 3D approach. The goal of this research project is to evaluate the factors that affect our current techniques as well as to adapt the development of inverse modulated techniques for our clinic, in which breast cancer patients are one of the largest populations treated. For this purpose, a dosimetric comparison along with the evaluation of immobilization devices was necessary. Radiation treatment plans were designed and dosimetrically compared for 5 patients in both, supine and prone positions. For 8 patients, VMAT and IMRT plans were created and evaluated in the supine position. Skin flash incorporation for inverse modulated plans required measurement of the surface dose as well as an evaluation of breast volume changes during a treatment course. It was found that prone 3D conformal plans as well as the VMAT and IMRT plans are generally superior in sparing OARs to supine plans with comparable PTV coverage. Prone setup leads to larger shifts in breast volume as well as in

  9. Is intensity-modulated radiotherapy better than conventional radiation treatment and three-dimensional conformal radiotherapy for mediastinal masses in patients with Hodgkin's disease, and is there a role for beam orientation optimization and dose constraints assigned to virtual volumes?

    SciTech Connect

    Girinsky, Theodore . E-mail: girinsky@igr.fr; Pichenot, Charlotte; Beaudre, Anne; Ghalibafian, Mithra; Lefkopoulos, Dimitri

    2006-01-01

    Purpose: To evaluate the role of beam orientation optimization and the role of virtual volumes (VVs) aimed at protecting adjacent organs at risk (OARs), and to compare various intensity-modulated radiotherapy (IMRT) setups with conventional treatment with anterior and posterior fields and three-dimensional conformal radiotherapy (3D-CRT). Methods and Materials: Patients with mediastinal masses in Hodgkin's disease were treated with combined modality therapy (three to six cycles of adriamycin, bleomycin, vinblastine, and dacarbazine [ABVD] before radiation treatment). Contouring and treatment planning were performed with Somavision and CadPlan Helios (Varian Systems, Palo Alto, CA). The gross tumor volume was determined according to the prechemotherapy length and the postchemotherapy width of the mediastinal tumor mass. A 10-mm isotropic margin was added for the planning target volume (PTV). Because dose constraints assigned to OARs led to unsatisfactory PTV coverage, VVs were designed for each patient to protect adjacent OARs. The prescribed dose was 40 Gy to the PTV, delivered according to guidelines from International Commission on Radiation Units and Measurements Report No. 50. Five different IMRT treatment plans were compared with conventional treatment and 3D-CRT. Results: Beam orientation was important with respect to the amount of irradiated normal tissues. The best compromise in terms of PTV coverage and protection of normal tissues was obtained with five equally spaced beams (5FEQ IMRT plan) using dose constraints assigned to VVs. When IMRT treatment plans were compared with conventional treatment and 3D-CRT, dose conformation with IMRT was significantly better, with greater protection of the heart, coronary arteries, esophagus, and spinal cord. The lungs and breasts in women received a slightly higher radiation dose with IMRT compared with conventional treatments. The greater volume of normal tissue receiving low radiation doses could be a cause for

  10. Pulmonary Toxicity in Stage III Non-Small Cell Lung Cancer Patients Treated With High-Dose (74 Gy) 3-Dimensional Conformal Thoracic Radiotherapy and Concurrent Chemotherapy Following Induction Chemotherapy: A Secondary Analysis of Cancer and Leukemia Group B (CALGB) Trial 30105

    SciTech Connect

    Salama, Joseph K.; Stinchcombe, Thomas E.; Gu Lin; Wang Xiaofei; Morano, Karen; Bogart, Jeffrey A.; Crawford, Jeffrey C.; Socinski, Mark A.; Blackstock, A. William; Vokes, Everett E.

    2011-11-15

    Purpose: Cancer and Leukemia Group B (CALGB) 30105 tested two different concurrent chemoradiotherapy platforms with high-dose (74 Gy) three-dimensional conformal radiotherapy (3D-CRT) after two cycles of induction chemotherapy for Stage IIIA/IIIB non-small cell lung cancer (NSCLC) patients to determine if either could achieve a primary endpoint of >18-month median survival. Final results of 30105 demonstrated that induction carboplatin and gemcitabine and concurrent gemcitabine 3D-CRT was not feasible because of treatment-related toxicity. However, induction and concurrent carboplatin/paclitaxel with 74 Gy 3D-CRT had a median survival of 24 months, and is the basis for the experimental arm in CALGB 30610/RTOG 0617/N0628. We conducted a secondary analysis of all patients to determine predictors of treatment-related pulmonary toxicity. Methods and Materials: Patient, tumor, and treatment-related variables were analyzed to determine their relation with treatment-related pulmonary toxicity. Results: Older age, higher N stage, larger planning target volume (PTV)1, smaller total lung volume/PTV1 ratio, larger V20, and larger mean lung dose were associated with increasing pulmonary toxicity on univariate analysis. Multivariate analysis confirmed that V20 and nodal stage as well as treatment with concurrent gemcitabine were associated with treatment-related toxicity. A high-risk group comprising patients with N3 disease and V20 >38% was associated with 80% of Grades 3-5 pulmonary toxicity cases. Conclusions: Elevated V20 and N3 disease status are important predictors of treatment related pulmonary toxicity in patients treated with high-dose 3D-CRT and concurrent chemotherapy. Further studies may use these metrics in considering patients for these treatments.

  11. Two-fraction high-dose-rate brachytherapy within a single day combined with external beam radiotherapy for prostate cancer: single institution experience and outcomes

    PubMed Central

    Liu, Junyang; Kaidu, Motoki; Sasamoto, Ryuta; Ayukawa, Fumio; Yamana, Nobuko; Sato, Hiraku; Tanaka, Kensuke; Kawaguchi, Gen; Ohta, Atsushi; Maruyama, Katsuya; Abe, Eisuke; Kasahara, Takashi; Nishiyama, Tsutomu; Tomita, Yoshihiko; Aoyama, Hidefumi

    2016-01-01

    We investigated the outcomes of treatment for patients with localized prostate cancer (PCa) treated with 3D conformal radiation therapy (3D-CRT) followed by two-fraction high-dose-rate brachytherapy within a single day (2-fr.-HDR-BT/day) at a single institution. A total of 156 consecutive Asian males (median age, 67 years) were enrolled. To compare our findings with those of other studies, we analyzed our results using the D'Amico classification, assigning the patients to low- (n =5; 3.2%), intermediate- (n =36; 23.1%) and high-risk (n =115; 73.7%) groups (Stage T3 PCa patients were classified as high-risk). One patient in the D'Amico low-risk group (20%), 13 intermediate-risk patients (36.1%) and 99 high-risk patients (86.1%) underwent androgen deprivation therapy. We administered a prescription dose of 39 Gy in 13 fractions of 3D-CRT combined with 18 Gy of HDR-BT in two 9-Gy fractions delivered within a single day. We did not distinguish between risk groups in determining the prescription dose. The median follow-up period was 38 months. Of the 156 patients, one died from primary disease and five died from other diseases. The 3-year overall survival (OS) rates were 100%, 100% and 93.7%, and the 3-year ‘biochemical no evidence of disease (bNED)’ rates were 100%, 100% and 96.9% for the D'Amico low-, intermediate- and high-risk groups, respectively. No patient developed ≥ Grade 3 early toxicity. The Grade 3 late genitourinary toxicity rate was 2.6%, and no ≥ Grade 3 late gastrointestinal toxicity occurred. The efficacy and safety of this study were satisfactory, and longer-term follow-up is necessary. PMID:26983988

  12. Single Photon Emission Computed Tomography-Based Three-Dimensional Conformal Radiotherapy for Hepatocellular Carcinoma With Portal Vein Tumor Thrombus

    SciTech Connect

    Shirai, Shintaro; Sato, Morio Suwa, Kazuhiro; Kishi, Kazushi; Shimono, Chigusa; Kawai, Nobuyuki; Tanihata, Hirohiko; Minamiguchi, Hiroki; Nakai, Motoki

    2009-03-01

    Purpose: To evaluate the safety and efficacy of three-dimensional conformal radiotherapy (3D-CRT) using single photon emission computed tomography (SPECT) in unresectable hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). Methods and Materials: Patients with HCC with PVTT in the first branch and/or main trunk were selected for this study. The optimal beam directions for 3D-CRT were explored using a Tc-99m-galactosyl human serum albumin SPECT image for guidance. The SPECT image was classified as either wedge type or localized type. The clinical target volume to a total dose of 45 or 50 Gy per 18-20 fractions included the main tumor and PVTT in the wedge type and PVTT alone in the localized type. Results: Twenty-six patients were enrolled: 18 with wedge type and 8 with localized type. Mean tumor size was 7.1 cm (range, 4.4-12.3 cm). Clinical target volumes of wedge type vs. localized type were 111.2 cm{sup 3} vs. 48.4 cm{sup 3} (p = 0.010), respectively. Mean dose to normal liver and mean dose to functional liver were 1185 cGy and 988 cGy (p = 0.001) in wedge type and 1046 cGy and 1043 cGy (p = 0.658) in localized type, respectively. Despite an incidence of Child-Pugh B and C of 57.7%, no patients experienced radiation-induced liver disease. The progression of PVTT was inhibited, with an incidence of 92.2%; survival rates at 1 and 2 years were 44% and 30%, respectively. Conclusion: Single photon emission computed tomography-based 3D-CRT enables irradiation of both the main tumor and PVTT with low toxicity and promising survival.

  13. [Radiotherapy of breast cancer].

    PubMed

    Hennequin, C; Barillot, I; Azria, D; Belkacémi, Y; Bollet, M; Chauvet, B; Cowen, D; Cutuli, B; Fourquet, A; Hannoun-Lévi, J M; Leblanc, M; Mahé, M A

    2016-09-01

    In breast cancer, radiotherapy is an essential component of the treatment. After conservative surgery for an infiltrating carcinoma, radiotherapy must be systematically performed, regardless of the characteristics of the disease, because it decreases the rate of local recurrence and by this way, specific mortality. Partial breast irradiation could not be proposed routinely but only in very selected and informed patients. For ductal carcinoma in situ, adjuvant radiotherapy must be also systematically performed after lumpectomy. After mastectomy, chest wall irradiation is required for pT3-T4 tumours and if there is an axillary nodal involvement, whatever the number of involved lymph nodes. After neo-adjuvant chemotherapy and mastectomy, in case of pN0 disease, chest wall irradiation is recommended if there is a clinically or radiologically T3-T4 or node positive disease before chemotherapy. Axillary irradiation is recommended only if there is no axillary surgical dissection and a positive sentinel lymph node. Supra and infra-clavicular irradiation is advised in case of positive axillary nodes. Internal mammary irradiation must be discussed case by case, according to the benefit/risk ratio (cardiac toxicity). Dose to the chest wall or the breast must be between 45-50Gy with a conventional fractionation. A boost dose over the tumour bed is required if the patient is younger than 60 years old. Hypofractionation (42.5 Gy in 16 fractions, or 41.6 Gy en 13 or 40 Gy en 15) is possible after tumorectomy and if a nodal irradiation is not mandatory. Delineation of the breast, the chest wall and the nodal areas are based on clinical and radiological evaluations. 3D-conformal irradiation is the recommended technique, intensity-modulated radiotherapy must be proposed only in case of specific clinical situations. Respiratory gating could be useful to decrease the cardiac dose. Concomitant administration of chemotherapy in unadvised, but hormonal treatment could be start with

  14. Feasibility and Efficacy of Single Photon Emission Computed Tomography-Based Three-Dimensional Conformal Radiotherapy for Hepatocellular Carcinoma 8 cm or More With Portal Vein Tumor Thrombus in Combination With Transcatheter Arterial Chemoembolization

    SciTech Connect

    Shirai, Shintaro; Sato, Morio; Suwa, Kazuhiro; Kishi, Kazushi; Shimono, Chigusa; Sonomura, Tetsuo; Kawai, Nobuyuki; Tanihata, Hirohiko; Minamiguchi, Hiroki; Nakai, Motoki

    2010-03-15

    Purpose: To assess the feasibility and efficacy of single photon emission computed tomography-based three-dimensional conformal radiotherapy (SPECT-B 3D-CRT) for large hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). Methods and Materials: HCC patients with PVTT in the first branch or main trunk, 8 cm or greater in size, were admitted to the study. SPECT, using Tc-99m-galactosyl human serum albumin, was used in radiation treatment planning to explore the optimal irradiation beam angle. SPECT enabled the minimum possible irradiation of functional liver (FL). Clinical target volume (CTV) included the main tumor and PVTT. SPECT-B 3D-CRT targeted the CTV to a total dose of 45 Gy/18 fractions. HCC outside the CTV was treated by transcatheter arterial chemoembolization (TACE). Results: Nineteen cases were enrolled in this study. The mean maximum dimension, mean CTV, and mean dose to FL were 11.0 cm (range, 8.0-20.0), 435 cm{sup 3} (range, 60-2,535), and 1,102 cGy (range, 691-1,695), respectively. Follow-up SPECT demonstrated radiation-induced dysfunctional liver. Despite the inclusion of 6 cases of Child-Pugh B or C, no patients experienced Grade 3 or worse radiation-induced liver disease. The cumulative non-progression rates of PVTT and PVTT plus main tumor were 78.0 and 43.2%, respectively. Survival rates at 1 and 2 years were 47.4 and 23.7%, respectively. Conclusions: SPECT-B 3D-CRT with TACE appears to be tolerable to cirrhotic liver and to provide promising prognosis for patients with HCC sized 8 cm or more, in comparison with previous treatment methods. A longer follow-up period is required to evaluate these findings.

  15. Prone Whole-Breast Irradiation Using Three-Dimensional Conformal Radiotherapy in Women Undergoing Breast Conservation for Early Disease Yields High Rates of Excellent to Good Cosmetic Outcomes in Patients With Large and/or Pendulous Breasts

    SciTech Connect

    Bergom, Carmen; Kelly, Tracy; Morrow, Natalya; Wilson, J. Frank; Walker, Alonzo; Xiang Qun; Ahn, Kwang Woo; White, Julia

    2012-07-01

    Purpose: To report our institution's experience using prone positioning for three-dimensional conformal radiotherapy (3D-CRT) to deliver post-lumpectomy whole breast irradiation (WBI) in a cohort of women with large and/or pendulous breasts, to determine the rate of acute and late toxicities and, more specifically, cosmetic outcomes. We hypothesized that using 3D-CRT for WBI in the prone position would reduce or eliminate patient and breast size as negative prognostic indicators for toxicities associated with WBI. Methods and Materials: From 1998 to 2006, 110 cases were treated with prone WBI using 3D-CRT. The lumpectomy, breast target volumes, heart, and lung were contoured on all computed tomography scans. A dose of 45-50 Gy was prescribed to the breast volume using standard fractionation schemes. The planning goals were {>=}95% of prescription to 95% of the breast volume, and 100% of boost dose to 95% of lumpectomy planning target volume. Toxicities and cosmesis were prospectively scored using the Common Terminology Criteria for Adverse Effects Version 3.0 and the Harvard Scale. The median follow-up was 40 months. Results: The median body mass index (BMI) was 33.6 kg/m{sup 2}, and median breast volume was 1396 cm{sup 3}. The worst toxicity encountered during radiation was Grade 3 dermatitis in 5% of our patient population. Moist desquamation occurred in 16% of patients, with only 2% of patients with moist desquamation outside the inframammary/axillary folds. Eleven percent of patients had Grade {>=}2 late toxicities, including Grade 3 induration/fibrosis in 2%. Excellent to good cosmesis was achieved in 89%. Higher BMI was associated with moist desquamation and breast pain, but BMI and breast volume did not impact fibrosis or excellent to good cosmesis. Conclusion: In patients with higher BMI and/or large-pendulous breasts, delivering prone WBI using 3D-CRT results in favorable toxicity profiles and high excellent to good cosmesis rates. Higher BMI was

  16. Intensity-Modulated Radiotherapy is Associated With Improved Global Quality of Life Among Long-term Survivors of Head-and-Neck Cancer

    SciTech Connect

    Chen, Allen M.; Farwell, D. Gregory; Luu, Quang; Vazquez, Esther G.; Lau, Derick H.; Purdy, James A.

    2012-09-01

    Purpose: To compare the long-term quality of life among patients treated with and without intensity-modulated radiotherapy (IMRT) for head-and-neck cancer. Methods and Materials: University of Washington Quality of Life instrument scores were reviewed for 155 patients previously treated with radiation therapy for locally advanced head-and-neck cancer. All patients were disease free and had at least 2 years of follow-up. Eighty-four patients (54%) were treated with IMRT. The remaining 71 patients (46%) were treated with three-dimensional conformal radiotherapy (3D CRT) by use of initial opposed lateral fields matched to a low anterior neck field. Results: The mean global quality of life scores were 67.5 and 80.1 for the IMRT patients at 1 and 2 years, respectively, compared with 55.4 and 57.0 for the 3D CRT patients, respectively (p < 0.001). At 1 year after the completion of radiation therapy, the proportion of patients who rated their global quality of life as 'very good' or 'outstanding' was 51% and 41% among patients treated by IMRT and 3DCRT, respectively (p = 0.11). At 2 years, the corresponding percentages increased to 73% and 49%, respectively (p < 0.001). On multivariate analysis accounting for sex, age, radiation intent (definitive vs. postoperative), radiation dose, T stage, primary site, use of concurrent chemotherapy, and neck dissection, the use of IMRT was the only variable independently associated with improved quality of life (p = 0.01). Conclusion: The early quality of life improvements associated with IMRT not only are maintained but apparently become more magnified over time. These data provide powerful evidence attesting to the long-term benefits of IMRT for head-and-neck cancer.

  17. Intensity-modulated radiation therapy and volumetric-modulated arc therapy for adult craniospinal irradiation—A comparison with traditional techniques

    SciTech Connect

    Studenski, Matthew T.; Shen, Xinglei; Yu, Yan; Xiao, Ying; Shi, Wenyin; Biswas, Tithi; Werner-Wasik, Maria; Harrison, Amy S.

    2013-04-01

    Craniospinal irradiation (CSI) poses a challenging planning process because of the complex target volume. Traditional 3D conformal CSI does not spare any critical organs, resulting in toxicity in patients. Here the dosimetric advantages of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) are compared with classic conformal planning in adults for both cranial and spine fields to develop a clinically feasible technique that is both effective and efficient. Ten adult patients treated with CSI were retrospectively identified. For the cranial fields, 5-field IMRT and dual 356° VMAT arcs were compared with opposed lateral 3D conformal radiotherapy (3D-CRT) fields. For the spine fields, traditional posterior-anterior (PA) PA fields were compared with isocentric 5-field IMRT plans and single 200° VMAT arcs. Two adult patients have been treated using this IMRT technique to date and extensive quality assurance, especially for the junction regions, was performed. For the cranial fields, the IMRT technique had the highest planned target volume (PTV) maximum and was the least efficient, whereas the VMAT technique provided the greatest parotid sparing with better efficiency. 3D-CRT provided the most efficient delivery but with the highest parotid dose. For the spine fields, VMAT provided the best PTV coverage but had the highest mean dose to all organs at risk (OAR). 3D-CRT had the highest PTV and OAR maximum doses but was the most efficient. IMRT provides the greatest OAR sparing but the longest delivery time. For those patients with unresectable disease that can benefit from a higher, definitive dose, 3D-CRT–opposed laterals are the most clinically feasible technique for cranial fields and for spine fields. Although inefficient, the IMRT technique is the most clinically feasible because of the increased mean OAR dose with the VMAT technique. Quality assurance of the beams, especially the junction regions, is essential.

  18. Three-dimensional conformal radiotherapy for locally advanced (Stage II and worse) head-and-neck cancer: Dosimetric and clinical evaluation

    SciTech Connect

    Portaluri, Maurizio . E-mail: portaluri@hotmail.com; Fucilli, Fulvio I.M.; Castagna, Roberta; Bambace, Santa; Pili, Giorgio; Tramacere, Francesco; Russo, Donatella; Francavilla, Maria Carmen

    2006-11-15

    Purpose: To evaluate the dosimetric parameters of three-dimensional conformal radiotherapy (3D-CRT) in locally advanced head-and-neck tumors (Stage II and above) and the effects on xerostomia. Methods and Materials: A total of 49 patients with histologically proven squamous cell cancer of the head and neck were consecutively treated with 3D-CRT using a one-point setup technique; 17 had larynx cancer, 12 oropharynx, 12 oral cavity, and 6 nasopharynx cancer; 2 had other sites of cancer. Of the 49 patients, 41 received postoperative RT and 8 definitive treatment. Also, 13 were treated with cisplatin-based chemotherapy before and during RT; in 6 cases, 5-fluorouracil was added. The follow-up time was 484-567 days (median, 530 days). Results: One-point setup can deliver 96% of the prescribed dose to the isocenter, to the whole planning target volume, including all node levels of the neck and without overdosages. The mean dose to the primary planning target volume was 49.54 {+-} 4.82 Gy (51.53 {+-} 5.47 Gy for larynx cases). The average dose to the contralateral parotid gland was approximately 38 Gy (30 Gy for larynx cases). The maximal dose to the spinal cord was 46 Gy. A Grade 0 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia score corresponded to a mean dose of 30 Gy to one parotid gland. A lower xerostomia score with a lower mean parotid dose and longer follow-up seemed to give rise to a sort of functional recovery phenomenon. Conclusion: Three dimensional-CRT in head-and-neck cancers permits good coverage of the planning target volume with about 10-11 segments and one isocenter. With a mean dose of approximately 30 Gy to the contralateral parotid, we observed no or mild xerostomia.

  19. High-Dose Conformal Radiotherapy for Patients With Stage III Non-Small-Cell Lung Carcinoma

    SciTech Connect

    Nakayama, Hidetsugu; Satoh, Hiroaki; Kurishima, Koichi; Ishikawa, Hiroichi; Tokuuye, Koichi

    2010-11-01

    Purpose: To determine the effectiveness of high-dose conformal radiotherapy to the involved field for patients with Stage III non-small-cell lung cancer (NSCLC). Methods and Materials: Between May 1999 and April 2006, a total of 100 consecutive patients with inoperable Stage IIIA or IIIB NSCLC with a performance score of 0 to 2 and treatment by radical radiotherapy combined with chemotherapy were included. Up to August 2002, 33 patients underwent conventional radiotherapy of 56 Gy to 66 Gy using anteroposterior opposite ports to the primary tumor and elective lymph nodes (conventional group). After September 2002, the remaining 67 patients underwent high-dose radiotherapy of 66 Gy to 84 Gy to the involved volume with three-dimensional (3-D) conformal radiotherapy (conformal group). Results: The median survival was 13.2 months (95% confidence interval [CI], 7.5-18.5 months) in the conventional group and 17.3 months (95% CI, 10.7- 24.0 months) in the conformal group. The overall survival at 3 years were 9.1% (95% CI, -0.7-18.9%) in the conventional group and 31.0% (95% CI, 18.9-43.1%) in the conformal group; the conformal group had a significantly better overall survival (p < 0.05). The radiotherapy method (hazard ratio = 0.55, p < 0.05) and performance status (hazard ratio = 1.48, p < 0.05) were shown to be statistically significant independent prognostic factors. Conclusions: Based on the practical experience reported here, 3-D conformal radiotherapy allowed dose escalation without excessive toxicity, and may improve overall survival rates for patients with Stage III NSCLC.

  20. Bilateral glomus tumor treated with PET-CT based conformal radiotherapy: a case report

    PubMed Central

    Yuksel, Oznur; Topkan, Erkan; Pehlivan, Berrin

    2009-01-01

    Introduction Glomus tumors are benign, slow growing tumors originating from paraganglionic tissue, mostly located at the carotid bifurcation, jugular foramen, cervical portion vagus nerve, and middle ear cavity. Radiotherapy is treatment of choice for patients with intracranial extension, and patients with bilateral and multiple tumors, or patients who are inoperable. Case presentation We present a 53-year-old female patient with a glomus tumor treated with positron emission tomography computed tomography planning and 3D conformal radiotherapy, and the patient has remained free of disease progression 2 years after. Conclusion It is suggested that radiotherapy is a good treatment modality in patients with glomus tumor, and metabolic imaging and treatment planning with positron emission tomography computed tomography is superior to other imaging modalities. PMID:19918426

  1. Risk of second primary cancer following prostate cancer radiotherapy: DVH analysis using the competitive risk model

    NASA Astrophysics Data System (ADS)

    Takam, R.; Bezak, E.; Yeoh, E. E.

    2009-02-01

    This study aimed to estimate the risk of developing second primary cancer (SPC) corresponding to various radiation treatment techniques for prostate cancer. Estimation of SPC was done by analysing differential dose-volume histograms (DDVH) of normal tissues such as rectum, bladder and urethra with the competitive risk model. Differential DVHs were obtained from treatment planning systems for external beam radiotherapy (EBRT), low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy techniques. The average risk of developing SPC was no greater than 0.6% for all treatment techniques but was lower with either LDR or HDR brachytherapy alone compared with any EBRT technique. For LDR and HDR brachytherapy alone, the risk of SPC for the rectum was 2.0 × 10-4% and 8.3 × 10-5% respectively compared with 0.2% for EBRT using five-field 3D-CRT to a total dose of 74 Gy. Overall, the risk of developing SPC for urethra following all radiation treatment techniques was very low compared with the rectum and bladder. Treatment plans which deliver equivalent doses of around 3-5 Gy to normal tissues were associated with higher risks of development of SPC.

  2. Measurement of Mean Cardiac Dose for Various Breast Irradiation Techniques and Corresponding Risk of Major Cardiovascular Event

    PubMed Central

    Merino Lara, Tomas Rodrigo; Fleury, Emmanuelle; Mashouf, Shahram; Helou, Joelle; McCann, Claire; Ruschin, Mark; Kim, Anthony; Makhani, Nadiya; Ravi, Ananth; Pignol, Jean-Philippe

    2014-01-01

    After breast conserving surgery, early stage breast cancer patients are currently treated with a wide range of radiation techniques including whole breast irradiation (WBI), accelerated partial breast irradiation (APBI) using high-dose rate (HDR) brachytherapy, or 3D-conformal radiotherapy (3D-CRT). This study compares the mean heart’s doses for a left breast irradiated with different breast techniques. An anthropomorphic Rando phantom was modified with gelatin-based breast of different sizes and tumors located medially or laterally. The breasts were treated with WBI, 3D-CRT, or HDR APBI. The heart’s mean doses were measured with Gafchromic films and controlled with optically stimulated luminescent dosimeters. Following the model reported by Darby (1), major cardiac were estimated assuming a linear risk increase with the mean dose to the heart of 7.4% per gray. WBI lead to the highest mean heart dose (2.99 Gy) compared to 3D-CRT APBI (0.51 Gy), multicatheter (1.58 Gy), and balloon HDR (2.17 Gy) for a medially located tumor. This translated into long-term coronary event increases of 22, 3.8, 11.7, and 16% respectively. The sensitivity analysis showed that the tumor location had almost no effect on the mean heart dose for 3D-CRT APBI and a minimal impact for HDR APBI. In case of WBI large breast size and set-up errors lead to sharp increases of the mean heart dose. Its value reached 10.79 Gy for women with large breast and a set-up error of 1.5 cm. Such a high value could increase the risk of having long-term coronary events by 80%. Comparison among different irradiation techniques demonstrates that 3D-CRT APBI appears to be the safest one with less probability of having cardiovascular events in the future. A sensitivity analysis showed that WBI is the most challenging technique for patients with large breasts or when significant set-up errors are anticipated. In those cases, additional heart shielding techniques are required. PMID:25374841

  3. Whole Pelvic Intensity-modulated Radiotherapy for Gynecological Malignancies: A Review of the Literature

    PubMed Central

    Hymel, Rockne; Jones, Guy C.; Simone, Charles B.

    2015-01-01

    Radiation therapy has long played a major role in the treatment of gynecological malignancies. There is increasing interest in the utility of intensity-modulated radiotherapy (IMRT) and its application to treat gynecological malignancies. Herein, we review the state-of-the-art use of IMRT for gynecological malignancies and report how it is being used alone as well as in combination with chemotherapy in both the adjuvant and definitive settings. Based on dosimetric and clinical evidence, IMRT can reduce gastrointestinal, genitourinary, and hematological toxicities compared with 3D conformal radiotherapy for gynecologic malignancies. We discuss how these attributes of IMRT may lead to improvements in disease outcomes by allowing for dose escalation of radiation therapy, intensification of chemotherapy, and limiting toxicity-related treatment breaks. Currently accruing trials investigating pelvic IMRT for cervical and endometrial cancers are discussed. PMID:25600840

  4. Estimate of the risk of radiation-induced cancers after linear-accelerator-based breast-cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Koh, Eui Kwan; Seo, Jungju; Baek, Tae Seong; Chung, Eun Ji; Yoon, Myonggeun; Lee, Hyun-ho

    2013-07-01

    The aim of this study is to assess and compare the excess absolute risks (EARs) of radiation-induced cancers following conformal (3D-CRT), fixed-field intensity-modulated (IMRT) and volumetric modulated arc (RapidArc) radiation therapy in patients with breast cancer. 3D-CRT, IMRT and RapidArc were planned for 10 breast cancer patients. The organ-specific EAR for cancer induction was estimated using the organ equivalent dose (OED) based on computed dose volume histograms (DVHs) and the secondary doses measured at various points from the field edge. The average secondary dose per Gy treatment dose from 3D-CRT, measured 10 to 50 cm from the field edge, ranged from 8.27 to 1.04 mGy. The secondary doses per Gy from IMRT and RapidArc, however, ranged between 5.86 and 0.54 mGy, indicating that IMRT and RapidArc are associated with smaller doses of secondary radiation than 3D-CRT. The organ specific EARs for out-of-field organs, such as the thyroid, liver and colon, were higher with 3D-CRT than with IMRT or RapidArc. In contrast, EARs for in-field organs were much lower with 3D-CRT than with IMRT or RapidArc. The overall estimate of EAR indicated that the radiation-induced cancer risk was 1.8-2.0 times lower with 3D-CRT than with IMRT or RapidArc. Comparisons of EARs during breast irradiation suggested that the predicted risk of secondary cancers was lower with 3D-CRT than with IMRT or RapidArc.

  5. A Pelvic Phantom for Modeling Internal Organ Motions

    SciTech Connect

    Kovacs, Peter; Sebestyen, Zsolt; Farkas, Robert; Bellyei, Szabolcs; Szigeti, Andras; Liposits, Gabor; Hideghety, Katalin; Derczy, Katalin; Mangel, Laszlo

    2011-10-01

    A pelvic phantom was developed for use in testing image-guided radiation therapy (IGRT) and adaptive applications in radiation therapy (ART) with simulating the anterior-posterior internal organ motions during prostate radiotherapy. Measurements could be done with an ionization chamber (IC) in the simulated prostate. The rectum was simulated by air-equivalent material (AEM). The volume superior to the IC placement was considered as the bladder. The extension of AEM volume could be varied. The vertical position of the IC placement could be shifted by {+-}1 cm to simulate the prostate motion parallel to the changes in bladder volume. The reality of the simulation was inspected. Three-millimeter-slice-increment computed tomography (CT) scans were taken for irradiation planning. The structure set was adapted to the phantom from a treated patient. Planning target volume was delineated according to the RTOG 0126 study. IMRT and 3D conformal radiation therapy (3D-CRT) plans were made. Prostate motion and rectum volume changes were simulated in the phantom. IC displacement was corrected by phantom shifting. The delivered dose was measured with IC in 7 cases using intensity-modulated radiation therapy (IMRT) and 3D-CRT fractions, and single square-shaped beams: anteroposterior (AP), posteroanterior (PA), and lateral (LAT). Variations from the calculated doses were slightly below 1% at IMRT and around 1% at 3D-CRT; below 4.5% at square AP beam; up to 9% at square PA beam; and around 0.5% at square LAT beam. Other authors have already shown that by using planning systems and ultrasonic and cone beam CT guidance, correction of organ motions in a real patient during prostate cancer IGRT does not have a significant dosimetric effect. The inspection of our phantom-as described here-ended with similar results. Our team suggested that our model is sufficiently realistic and can be used for IGRT and ART testing.

  6. Dynamic targeting image-guided radiotherapy

    SciTech Connect

    Huntzinger, Calvin; Munro, Peter; Johnson, Scott; Miettinen, Mika; Zankowski, Corey; Ahlstrom, Greg; Glettig, Reto; Filliberti, Reto; Kaissl, Wolfgang; Kamber, Martin; Amstutz, Martin; Bouchet, Lionel; Klebanov, Dan; Mostafavi, Hassan; Stark, Richard

    2006-07-01

    Volumetric imaging and planning for 3-dimensional (3D) conformal radiotherapy and intensity-modulated radiotherapy (IMRT) have highlighted the need to the oncology community to better understand the geometric uncertainties inherent in the radiotherapy delivery process, including setup error (interfraction) as well as organ motion during treatment (intrafraction). This has ushered in the development of emerging technologies and clinical processes, collectively referred to as image-guided radiotherapy (IGRT). The goal of IGRT is to provide the tools needed to manage both inter- and intrafraction motion to improve the accuracy of treatment delivery. Like IMRT, IGRT is a process involving all steps in the radiotherapy treatment process, including patient immobilization, computed tomogaphy (CT) simulation, treatment planning, plan verification, patient setup verification and correction, delivery, and quality assurance. The technology and capability of the Dynamic Targeting{sup TM} IGRT system developed by Varian Medical Systems is presented. The core of this system is a Clinac (registered) or Trilogy{sup TM} accelerator equipped with a gantry-mounted imaging system known as the On-Board Imager{sup TM} (OBI). This includes a kilovoltage (kV) x-ray source, an amorphous silicon kV digital image detector, and 2 robotic arms that independently position the kV source and imager orthogonal to the treatment beam. A similar robotic arm positions the PortalVision{sup TM} megavoltage (MV) portal digital image detector, allowing both to be used in concert. The system is designed to support a variety of imaging modalities. The following applications and how they fit in the overall clinical process are described: kV and MV planar radiographic imaging for patient repositioning, kV volumetric cone beam CT imaging for patient repositioning, and kV planar fluoroscopic imaging for gating verification. Achieving image-guided motion management throughout the radiation oncology process

  7. Model-based risk assessment for motion effects in 3D radiotherapy of lung tumors

    NASA Astrophysics Data System (ADS)

    Werner, René; Ehrhardt, Jan; Schmidt-Richberg, Alexander; Handels, Heinz

    2012-02-01

    Although 4D CT imaging becomes available in an increasing number of radiotherapy facilities, 3D imaging and planning is still standard in current clinical practice. In particular for lung tumors, respiratory motion is a known source of uncertainty and should be accounted for during radiotherapy planning - which is difficult by using only a 3D planning CT. In this contribution, we propose applying a statistical lung motion model to predict patients' motion patterns and to estimate dosimetric motion effects in lung tumor radiotherapy if only 3D images are available. Being generated based on 4D CT images of patients with unimpaired lung motion, the model tends to overestimate lung tumor motion. It therefore promises conservative risk assessment regarding tumor dose coverage. This is exemplarily evaluated using treatment plans of lung tumor patients with different tumor motion patterns and for two treatment modalities (conventional 3D conformal radiotherapy and step-&- shoot intensity modulated radiotherapy). For the test cases, 4D CT images are available. Thus, also a standard registration-based 4D dose calculation is performed, which serves as reference to judge plausibility of the modelbased 4D dose calculation. It will be shown that, if combined with an additional simple patient-specific breathing surrogate measurement (here: spirometry), the model-based dose calculation provides reasonable risk assessment of respiratory motion effects.

  8. A Retrospective Analysis on Two-week Short-course Pre-operative Radiotherapy in Elderly Patients with Resectable Locally Advanced Rectal Cancer

    PubMed Central

    Shi, Chen; Zhou, Hao; Li, Xiaofan; Cai, Yong

    2016-01-01

    To validate that a two-week short-course pre-operative radiotherapy regimen is feasible, safe, and effective for the management of elderly patients with locally advanced rectal cancer (LARC), we retrospectively analyzed 99 radiotherapy-naive patients ≥70 years of age with LARC. Patients received pelvic radiation therapy (3D-CRT 30Gy/10f/2w) followed by TME surgery; some patients received adjuvant chemotherapy. The primary endpoint was OS, while the secondary endpoints were DFS, safety and response rate. The median follow-up time was 5.1 years. The 5-year OS and DFS rates were 58.3% and 51.2%, respectively. The completion rate of radiotherapy (RT) was 99.0% (98 of 99). Grade 3 acute adverse events, which resulted from RT, occurred in only 1 patient (1.0%). In addition, no grade 4 acute adverse events induced by RT were observed. All 99 patients (100%) were able to undergo R0 surgical resection, and 68.6% of the patients received sphincter-sparing surgery. The rate of occurrence of clinically relevant post-operative complications was 12.1%. Three patients (3.0%) achieved pathologic complete responses, and forty-three patients (43.4%) achieved pathologic partial responses. The rates of T-downsizing and N-downstaging were 30.3% and 55.7%, respectively. Therefore, we believe that a two-week short-course pre-operative radiotherapy is feasible in elderly patients with resectable LARC. PMID:27886277

  9. Reduced late rectal mucosal changes after prostate three-dimensional conformal radiotherapy with endorectal balloon as observed in repeated endoscopy

    SciTech Connect

    Lin, Emile van . E-mail: E.vanLin@rther.umcn.nl; Kristinsson, Jon; Philippens, Marielle E.P.; Jong, Dirk J. de; Vight, Lisette P. van der; Kaanders, Johannes; Leer, Jan Willem; Visser, Andries G.

    2007-03-01

    Purpose: The aim of this study was to investigate prospectively the rectal wall (Rwall) spatial dose distribution, toxicity, and mucosal changes after prostate cancer radiotherapy with or without an endorectal balloon (ERB). Methods and Materials: A total of 24 patients with ERB and 24 without ERB (No-ERB) were treated with three-dimensional conformal radiotherapy (3D-CRT) to a dose of 67.5 Gy. The Rwall was divided into 16 mucosal areas and Rwall dose surface maps were constructed. After 3 months, 6 months, 1 year, and 2 years a rectosigmoidoscopy was performed, and each mucosal area was scored on telangiectasia, congestion, ulceration, stricture, and necrosis. Late rectal toxicity was correlated with the endoscopic findings. Results: The ERB significantly reduced the Rwall volume exposed to doses >40 Gy. Late rectal toxicity (grade {>=}1, including excess of bowel movements and slight rectal discharge) was reduced significantly in the ERB group. A total of 146 endoscopies and 2,336 mucosal areas were analyzed. Telangiectases were most frequently seen and appeared after 6 months. At 1 and 2 years, significantly less high-grade telangiectasia (T 2-3) was observed in the ERB group at the lateral and posterior part of the Rwall. In mucosal areas exposed to doses >40 Gy, less high-grade telangiectases (T 2-3) were seen in the ERB group compared with the No-ERB group. Conclusions: An ERB reduced the Rwall volume exposed to doses >40 Gy, resulting in reduction of late rectal mucosal changes and reduced late rectal toxicity. Although further analysis is needed, these data suggest an ERB-induced increased tolerance for late Rwall damage.

  10. The Impact of Dose Escalation on Secondary Cancer Risk After Radiotherapy of Prostate Cancer

    SciTech Connect

    Schneider, Uwe . E-mail: uwe.schneider@psi.ch; Lomax, Antony; Besserer, Juergen; Pemler, Peter; Lombriser, Norbert; Kaser-Hotz, Barbara D.V.M.

    2007-07-01

    Purpose: To estimate secondary cancer risk due to dose escalation in patients treated for prostatic carcinoma with three-dimensional conformal radiotherapy (3D-CRT), intensity-modulated RT (IMRT), and spot-scanned proton RT. Methods and Materials: The organ equivalent dose (OED) concept with a linear-exponential, a plateau, and a linear dose-response curve was applied to dose distributions of 23 patients who received RT of prostate cancer. Conformal RT was used in 7 patients, 8 patients received IMRT with 6- and 15-MV photons, and 8 patients were treated with spot-scanned protons. We applied target doses ranging from 70 Gy to 100 Gy. Cancer risk was estimated as a function of target dose and tumor control probability. Results: At a 100-Gy target dose the secondary cancer risk relative to the 3D treatment plan at 70 Gy was +18.4% (15.0% for a plateau model, 22.3% for a linear model) for the 6-MV IMRT plan, +25.3% (17.0%, 14.1%) for the 15-MV IMRT plan, and -40.7% (-41.3%, -40.0%) for the spot-scanned protons. The increasing risk of developing a radiation-associated malignancy after RT with increasing dose was balanced by the enhanced cure rates at a larger dose. Conclusions: Cancer risk after dose escalation for prostate RT is expected to be equal to or lower than for conventional 3D treatment at 70 Gy, independent of treatment modality or dose-response model. Spot-scanned protons are the treatment of choice for dose escalation because this therapy can halve the risk of secondary cancers.

  11. Development of the DVH management software for the biologically-guided evaluation of radiotherapy plan

    PubMed Central

    Kim, BoKyong; Park, Hee Chul; Oh, Dongryul; Shin, Eun Hyuk; Ahn, Yong Chan; Kim, Jinsung

    2012-01-01

    Purpose To develop the dose volume histogram (DVH) management software which guides the evaluation of radiotherapy (RT) plan of a new case according to the biological consequences of the DVHs from the previously treated patients. Materials and Methods We determined the radiation pneumonitis (RP) as an biological response parameter in order to develop DVH management software. We retrospectively reviewed the medical records of lung cancer patients treated with curative 3-dimensional conformal radiation therapy (3D-CRT). The biological event was defined as RP of the Radiation Therapy Oncology Group (RTOG) grade III or more. Results The DVH management software consisted of three parts (pre-existing DVH database, graphical tool, and Pinnacle3 script). The pre-existing DVH data were retrieved from 128 patients. RP events were tagged to the specific DVH data through retrospective review of patients' medical records. The graphical tool was developed to present the complication histogram derived from the pre-existing database (DVH and RP) and was implemented into the radiation treatment planning (RTP) system, Pinnacle3 v8.0 (Phillips Healthcare). The software was designed for the pre-existing database to be updated easily by tagging the specific DVH data with the new incidence of RP events at the time of patients' follow-up. Conclusion We developed the DVH management software as an effective tool to incorporate the phenomenological consequences derived from the pre-existing database in the evaluation of a new RT plan. It can be used not only for lung cancer patients but also for the other disease site with different toxicity parameters. PMID:23120743

  12. Dose enhancement in radiotherapy of small lung tumors using inline magnetic fields: A Monte Carlo based planning study

    SciTech Connect

    Oborn, B. M.; Ge, Y.; Hardcastle, N.; Metcalfe, P. E.; Keall, P. J.

    2016-01-15

    Purpose: To report on significant dose enhancement effects caused by magnetic fields aligned parallel to 6 MV photon beam radiotherapy of small lung tumors. Findings are applicable to future inline MRI-guided radiotherapy systems. Methods: A total of eight clinical lung tumor cases were recalculated using Monte Carlo methods, and external magnetic fields of 0.5, 1.0, and 3 T were included to observe the impact on dose to the planning target volume (PTV) and gross tumor volume (GTV). Three plans were 6 MV 3D-CRT plans while 6 were 6 MV IMRT. The GTV’s ranged from 0.8 to 16 cm{sup 3}, while the PTV’s ranged from 1 to 59 cm{sup 3}. In addition, the dose changes in a 30 cm diameter cylindrical water phantom were investigated for small beams. The central 20 cm of this phantom contained either water or lung density insert. Results: For single beams, an inline magnetic field of 1 T has a small impact in lung dose distributions by reducing the lateral scatter of secondary electrons, resulting in a small dose increase along the beam. Superposition of multiple small beams leads to significant dose enhancements. Clinically, this process occurs in the lung tissue typically surrounding the GTV, resulting in increases to the D{sub 98%} (PTV). Two isolated tumors with very small PTVs (3 and 6 cm{sup 3}) showed increases in D{sub 98%} of 23% and 22%. Larger PTVs of 13, 26, and 59 cm{sup 3} had increases of 9%, 6%, and 4%, describing a natural fall-off in enhancement with increasing PTV size. However, three PTVs bounded to the lung wall showed no significant increase, due to lack of dose enhancement in the denser PTV volume. In general, at 0.5 T, the GTV mean dose enhancement is around 60% lower than that at 1 T, while at 3 T, it is 5%–60% higher than 1 T. Conclusions: Monte Carlo methods have described significant and predictable dose enhancement effects in small lung tumor plans for 6 MV radiotherapy when an external inline magnetic field is included. Results of this study

  13. Applicator-guided volumetric-modulated arc therapy for low-risk endometrial cancer

    SciTech Connect

    Cilla, Savino; Macchia, Gabriella; Sabatino, Domenico; Digesù, Cinzia; Deodato, Francesco; Piermattei, Angelo; De Spirito, Marco; Morganti, Alessio G.

    2013-04-01

    The aim of this study was to report the feasibility of volumetric-modulated arc therapy (VMAT) in the postoperative irradiation of the vaginal vault. Moreover, the VMAT technique was compared with 3D conformal radiotherapy (3D-CRT) and fixed-field intensity-modulated radiotherapy (IMRT), in terms of target coverage and organs at risk sparing. The number of monitor units and the delivery time were analyzed to score the treatment efficiency. All plans were verified in a dedicated solid water phantom using a 2D array of ionization chambers. Twelve patients with endometrial carcinoma who underwent radical hystero-adenexectomy and fixed-field IMRT treatments were retrospectively included in this analysis; for each patient, plans were compared in terms of dose-volume histograms, homogeneity index, and conformity indexes. All techniques met the prescription goal for planning target volume coverage, with VMAT showing the highest level of conformity at all dose levels. VMAT resulted in significant reduction of rectal and bladder volumes irradiated at all dose levels compared with 3D-CRT. No significant differences were found with respect to IMRT. Moreover, a significant improvement of the dose conformity was reached by VMAT technique not only at the 95% dose level (0.74 vs. 0.67 and 0.62) but also at 50% and 75% levels of dose prescription. In addition, VMAT plans showed a significant reduction of monitor units by nearly 28% with respect to IMRT, and reduced treatment time from 11 to <3 minutes for a single 6-Gy fraction. In conclusion, VMAT plans can be planned and carried out with high quality and efficiency for the irradiation of vaginal vault alone, providing similar or better sparing of organs at risk to fixed-field IMRT and resulting in the most efficient treatment option. VMAT is currently our standard approach for radiotherapy of low-risk endometrial cancer.

  14. Pattern of radiotherapy care in Bulgaria.

    PubMed

    Hadjieva, Tatiana

    2015-01-01

    The paper reveals the changing pattern of Bulgarian Radiotherapy (RT) care after the successful implementation of 15 projects for 100 million euro under the European Regional Development Fund in Operational Programme for Regional Development 2007-2013. The project enables a total one-step modernization of 14 Bulgarian RT Centres and creation of a new one. At the end of the Programme (mid 2015), 16 new Linacs and 2 modern cobalt machines will be available together with 11 virtual CT simulators, 5 CT simulators, 1 MRI and 1 PET CT for RT planning and all dosimetry facilities needed. Such a modernization has moved Bulgarian RT forward, with 2.7 MV units per one million of population (MV/mln.inh) in comparison with 0.9 MV/mln.inh in 2012. Guild of Bulgarian Radiotherapists includes 70 doctors, 46 physicists and 10 engineers, together with 118 RTTs and 114 nurses and they all have treated 16,447 patients in 2013. Major problems are inadequate reimbursement from the monopolistic Health Insurance Fund (900 euro for 3D conformal RT and 1500 euro for IMRT); fragmentation of RT care with 1-2 MV units per Centre; no payment for patient travel expenses; need for quick and profound education of 26% of doctors and 46% of physicists without RT license, along with continuous education for all others; and resource for 5000-9000 more patients to be treated yearly by RT in order to reach 45-50% from current service of 32%. After 15 years of struggle of RT experts, finally the pattern of Bulgarian RT care at 2014-2015 is approaching the level of modern European RT.

  15. SU-E-J-267: Weekly Volumetric and Dosimetric Changes in Adaptive Conformal Radiotherapy of Non-Small-Cell-Lung Cancer Using 4D CT and Gating

    SciTech Connect

    Li, Z; Shang, Q; Xiong, F; Zhang, X; Zhang, Q; Fu, S

    2014-06-01

    Purpose: This study was to evaluate the significance of weekly imageguided patient setup and to assess the volumetric and dosimetric changes in no-small-cell-lung cancer (NSCLC) patients treated with adaptive conformal radiotherapy (CRT). Methods: 9 NSCLC patients treated with 3D CRT underwent 4D CT-on-rail every five fractions. ITV was generated from three phases of the 4DCT (the end of exhalation, 25% before and after the end of exhalation). The margin of ITV to PTV is 5mm. 6 weekly CTs were acquired for each patient. The weekly CTs were fused with the planning CT by vertebrae. The couch shift was recorded for each weekly CT to evaluate the setup error. The gross tumor volumes (GTVs) were contoured on weekly CT images by a physician. Beams from the original plans were applied to weekly CTs to calculate the delivered doses. All patients underwent replanning after 20 fractions. Results: Among the total 54 CTs, the average setup error was 2.0± 1.7, 2.6± 2.1, 2.7± 2.2 mm in X, Y, and Z direction, respectively. The average volume of the primary GTV was reduced from 42.45 cc to 22.78 cc (47.04%) after 6 weeks. The maximal volume regression occurred between 15 and 20 fractions. Adaptive radiation therapy (ART) reduced the V20 and V5 of the lung by 33.5% and 16.89%, respectively. ART also reduced Dmean and D1/3 of the heart by 31.7% and 32.32%, respectively. Dmax of the spinal cord did not vary much during the treatment course. Conclusion: 5 mm margin is sufficient for 4D weekly CTguided radiotherapy in lung cancer. Tumor regression was observed in the majority of patients. ART significantly reduced the OARs dose. Our preliminary results indicated that an off-line ART approach is appropriate in clinical practice.

  16. SU-E-T-84: A Survey On Radiotherapy Table Tolerances and Couch Overrides of Over 350 Institutions

    SciTech Connect

    Chinsky, B; Patel, R; Panfil, J; Surucu, M; Roeske, J

    2015-06-15

    Purpose: Table overrides are relatively common in radiotherapy, yet are a potential safety concern. The goal of this study was to survey current departmental policies on treatment couch overrides and table tolerance values used clinically. Methods: A 25 question electronic survey on couch overrides and tolerances was sent to full members of the AAPM. In the first part of the survey, participants were asked: if table overrides were allowed at their institution, who was allowed to perform these overrides, and if imaging was required with overrides. In the second part of the survey, individuals were asked to provide table tolerance data for the following sites: brain/head & neck, lung, breast, abdomen/pelvis and prostate. Each site was further divided into IMRT/VMAT and 3D conformal techniques. Free-text spaces were provided, allowing respondents to enter any table tolerance data they were unable to specify under the treatment sites listed. Results: A total of 361 individuals responded, of which approximately half participated in the couch tolerances portion of the survey. Overall, 86% of respondents’ institutions allow couch tolerance overrides at treatment. Therapists were the most common staff members permitted to perform overrides, followed by physicists, dosimetrists, and physicians, respectively. Of the institutions allowing overrides, 34% reported overriding daily. More than half of the centers require documentation of the override and/or a setup image (acquired after override) to radiographically verify the treatment site. With respect to table tolerances, groups resulting from the free-text responses were at the two extremes; SRS/SBRT were the tightest, while clinical setup/mets/extremities were the most generous. There was no qualitative difference between IMRT/VMAT and 3D conformal table tolerances. Conclusion: This work is intended to stimulate a discussion within the radiotherapy community. This discussion, supplemented by the survey results provides an

  17. Routine EPID in-vivo dosimetry in a reference point for conformal radiotherapy treatments

    NASA Astrophysics Data System (ADS)

    Fidanzio, Andrea; Azario, Luigi; Greco, Francesca; Cilla, Savino; Piermattei, Angelo

    2015-04-01

    In-vivo dosimetry (IVD) in external beam radiotherapy is used to detect major clinically relevant differences between planned and delivered dose. Moreover, a detailed analysis of its results, when routinely reported and discussed by the radiotherapy staff, can limit the likelihood of error transmission to many treatments. A first experience of routine EPID-based IVD in a reference point has been performed in our department for 3D-CRT treatments over a three-year period. More than 14 000 images were acquired and 1287 treatment plans were verified. The IVD checks were obtained three times in the first week and then weekly. Tolerance levels of ±5% for pelvic-abdomen, head-neck and breast irradiations and ±6% for lung treatments were adopted for the in-vivo measured dose per fraction. A statistical analysis of the IVD results was performed grouping the data by: anatomical regions, treatment units, open and wedged fields and gantry angles. About 10% of the checked doses per fraction showed dosimetric discrepancies out of the tolerance levels. The causes of the discrepancies were 70% delivery or planning errors, 20% morphological changes and 10% procedural limitations. 41 cases (3.2%) have required special investigations because their in-vivo doses per fraction, averaged over the first three sessions, were out of the tolerance levels and in 19 cases (1.5%) the deviations gave rise to an intervention. Statistically significant differences of average variations between planned and delivered doses were observed for: (i) 30° wedged 10 MV fields with respect to those of other wedged or open 10 MV fields delivered by two linacs, due to the incorrect TPS implementation of that wedge transmission factor; (ii) anterior-posterior and posterior-anterior beams with respect to the other gantry orientations for one linac, due to the beam attenuation introduced by the treatment couch; (iii) lateral fields with respect to medial fields of breast irradiations for all linacs, due

  18. Routine EPID in-vivo dosimetry in a reference point for conformal radiotherapy treatments.

    PubMed

    Fidanzio, Andrea; Azario, Luigi; Greco, Francesca; Cilla, Savino; Piermattei, Angelo

    2015-04-21

    In-vivo dosimetry (IVD) in external beam radiotherapy is used to detect major clinically relevant differences between planned and delivered dose. Moreover, a detailed analysis of its results, when routinely reported and discussed by the radiotherapy staff, can limit the likelihood of error transmission to many treatments. A first experience of routine EPID-based IVD in a reference point has been performed in our department for 3D-CRT treatments over a three-year period. More than 14,000 images were acquired and 1287 treatment plans were verified. The IVD checks were obtained three times in the first week and then weekly. Tolerance levels of ± 5% for pelvic-abdomen, head-neck and breast irradiations and ± 6% for lung treatments were adopted for the in-vivo measured dose per fraction. A statistical analysis of the IVD results was performed grouping the data by: anatomical regions, treatment units, open and wedged fields and gantry angles. About 10% of the checked doses per fraction showed dosimetric discrepancies out of the tolerance levels. The causes of the discrepancies were 70% delivery or planning errors, 20% morphological changes and 10% procedural limitations. 41 cases (3.2%) have required special investigations because their in-vivo doses per fraction, averaged over the first three sessions, were out of the tolerance levels and in 19 cases (1.5%) the deviations gave rise to an intervention. Statistically significant differences of average variations between planned and delivered doses were observed for: (i) 30° wedged 10 MV fields with respect to those of other wedged or open 10 MV fields delivered by two linacs, due to the incorrect TPS implementation of that wedge transmission factor; (ii) anterior-posterior and posterior-anterior beams with respect to the other gantry orientations for one linac, due to the beam attenuation introduced by the treatment couch; (iii) lateral fields with respect to medial fields of breast irradiations for all linacs, due to

  19. Factors influencing conformity index in radiotherapy for non-small cell lung cancer.

    PubMed

    Brennan, Sinead M; Thirion, Pierre; Buckney, Steve; Shea, Carmel O; Armstrong, John

    2010-01-01

    The radiotherapy conformity index (CI) is a useful tool to quantitatively assess the quality of radiotherapy treatment plans, and represents the relationship between isodose distributions and target volume. A conformity index of unity implies high planning target volume (PTV) coverage and minimal unnecessary irradiation of surrounding tissues. We performed this analysis to describe the CI for lung cancer 3-dimensional conformal radiotherapy (3DCRT) and to identify clinical and technical determinants of CI, as it is not known which factors are associated with good quality 3D conformal radiotherapy treatment planning. Radiotherapy treatment plans from a database of 52 patients with inoperable Stage 1 to 3b lung cancer, on a hypofractionated 3DCRT trial were evaluated. A CI was calculated for all plans using the definition of the ICRU 62:CI = (TV/PTV), which is the quotient of the treated volume (TV) and the PTV. Data on patient, tumor, and planning variables, which could influence CI, were recorded and analyzed. Mean CI was 2.01 (range = 1.06-3.8). On univariate analysis, PTV (p = 0.023), number of beams (p = 0.036), medial vs. lateral tumor location (p = 0.016), and increasing tumor stage (p = 0.041) were associated with improved conformity. On multiple regression analysis, factors found to be associated with CI included central vs. peripheral tumor location (p = 0.041) and PTV size (p = 0.058). The term 3DCRT is used routinely in the literature, without any indication of the degree of conformality. We recommend routine reporting of conformity indices. Conformity indices may be affected by both planning variables and tumor factors.

  20. Factors Influencing Conformity Index in Radiotherapy for Non-Small Cell Lung Cancer

    SciTech Connect

    Brennan, Sinead M. Thirion, Pierre; Buckney, Steve; Shea, Carmel O.; Armstrong, John

    2010-04-01

    The radiotherapy conformity index (CI) is a useful tool to quantitatively assess the quality of radiotherapy treatment plans, and represents the relationship between isodose distributions and target volume. A conformity index of unity implies high planning target volume (PTV) coverage and minimal unnecessary irradiation of surrounding tissues. We performed this analysis to describe the CI for lung cancer 3-dimensional conformal radiotherapy (3DCRT) and to identify clinical and technical determinants of CI, as it is not known which factors are associated with good quality 3D conformal radiotherapy treatment planning. Radiotherapy treatment plans from a database of 52 patients with inoperable Stage 1 to 3b lung cancer, on a hypofractionated 3DCRT trial were evaluated. A CI was calculated for all plans using the definition of the ICRU 62:CI = (TV/PTV), which is the quotient of the treated volume (TV) and the PTV. Data on patient, tumor, and planning variables, which could influence CI, were recorded and analyzed. Mean CI was 2.01 (range = 1.06-3.8). On univariate analysis, PTV (p = 0.023), number of beams (p = 0.036), medial vs. lateral tumor location (p = 0.016), and increasing tumor stage (p = 0.041) were associated with improved conformity. On multiple regression analysis, factors found to be associated with CI included central vs. peripheral tumor location (p = 0.041) and PTV size (p = 0.058). The term 3DCRT is used routinely in the literature, without any indication of the degree of conformality. We recommend routine reporting of conformity indices. Conformity indices may be affected by both planning variables and tumor factors.

  1. Results of patient specific quality assurance for patients undergoing stereotactic ablative radiotherapy for lung lesions.

    PubMed

    Hardcastle, Nicholas; Clements, Natalie; Chesson, Brent; Aarons, Yolanda; Cramb, Jim; Siva, Shankar; Wanigaratne, Derrick M; Ball, David; Kron, Tomas

    2014-03-01

    Hypofractionated image guided radiotherapy of extracranial targets has become increasingly popular as a treatment modality for inoperable patients with one or more small lesions, often referred to as stereotactic ablative body radiotherapy (SABR). This report details the results of the physical quality assurance (QA) program used for the first 33 lung cancer SABR radiotherapy 3D conformal treatment plans in our centre. SABR involves one or few fractions of high radiation dose delivered in many small fields or arcs with tight margins to mobile targets often delivered through heterogeneous media with non-coplanar beams. We have conducted patient-specific QA similar to the more common intensity modulated radiotherapy QA with particular reference to motion management. Individual patient QA was performed in a Perspex phantom using point dose verification with an ionisation chamber and radiochromic film for verification of the dose distribution both with static and moving detectors to verify motion management strategies. While individual beams could vary by up to 7%, the total dose in the target was found to be within ±2% of the prescribed dose for all 33 plans. Film measurements showed qualitative and quantitative agreement between planned and measured isodose line shapes and dimensions. The QA process highlighted the need to account for couch transmission and demonstrated that the ITV construction was appropriate for the treatment technique used. QA is essential for complex radiotherapy deliveries such as SABR. We found individual patient QA helpful in setting up the technique and understanding potential weaknesses in SABR workflow, thus providing confidence in SABR delivery.

  2. Dose calculation accuracy using cone-beam CT (CBCT) for pelvic adaptive radiotherapy

    NASA Astrophysics Data System (ADS)

    Guan, Huaiqun; Dong, Hang

    2009-10-01

    This study is to evaluate the dose calculation accuracy using Varian's cone-beam CT (CBCT) for pelvic adaptive radiotherapy. We first calibrated the Hounsfield Unit (HU) to electron density (ED) for CBCT using a mini CT QC phantom embedded into an IMRT QA phantom. We then used a Catphan 500 with an annulus around it to check the calibration. The combined CT QC and IMRT phantom provided correct HU calibration, but not Catphan with an annulus. For the latter, not only was the Teflon an incorrect substitute for bone, but the inserts were also too small to provide correct HUs for air and bone. For the former, three different scan ranges (6 cm, 12 cm and 20.8 cm) were used to investigate the HU dependence on the amount of scatter. To evaluate the dose calculation accuracy, CBCT and plan-CT for a pelvic phantom were acquired and registered. The single field plan, 3D conformal and IMRT plans were created on both CT sets. Without inhomogeneity correction, the two CT generated nearly the same plan. With inhomogeneity correction, the dosimetric difference between the two CT was mainly from the HU calibration difference. The dosimetric difference for 6 MV was found to be the largest for the single lateral field plan (maximum 6.7%), less for the 3D conformal plan (maximum 3.3%) and the least for the IMRT plan (maximum 2.5%). Differences for 18 MV were generally 1-2% less. For a single lateral field, calibration with 20.8 cm achieved the minimum dosimetric difference. For 3D and IMRT plans, calibration with a 12 cm range resulted in better accuracy. Because Catphan is the standard QA phantom for the on-board imager (OBI) device, we specifically recommend not using it for the HU calibration of CBCT.

  3. Dose calculation accuracy using cone-beam CT (CBCT) for pelvic adaptive radiotherapy.

    PubMed

    Guan, Huaiqun; Dong, Hang

    2009-10-21

    This study is to evaluate the dose calculation accuracy using Varian's cone-beam CT (CBCT) for pelvic adaptive radiotherapy. We first calibrated the Hounsfield Unit (HU) to electron density (ED) for CBCT using a mini CT QC phantom embedded into an IMRT QA phantom. We then used a Catphan 500 with an annulus around it to check the calibration. The combined CT QC and IMRT phantom provided correct HU calibration, but not Catphan with an annulus. For the latter, not only was the Teflon an incorrect substitute for bone, but the inserts were also too small to provide correct HUs for air and bone. For the former, three different scan ranges (6 cm, 12 cm and 20.8 cm) were used to investigate the HU dependence on the amount of scatter. To evaluate the dose calculation accuracy, CBCT and plan-CT for a pelvic phantom were acquired and registered. The single field plan, 3D conformal and IMRT plans were created on both CT sets. Without inhomogeneity correction, the two CT generated nearly the same plan. With inhomogeneity correction, the dosimetric difference between the two CT was mainly from the HU calibration difference. The dosimetric difference for 6 MV was found to be the largest for the single lateral field plan (maximum 6.7%), less for the 3D conformal plan (maximum 3.3%) and the least for the IMRT plan (maximum 2.5%). Differences for 18 MV were generally 1-2% less. For a single lateral field, calibration with 20.8 cm achieved the minimum dosimetric difference. For 3D and IMRT plans, calibration with a 12 cm range resulted in better accuracy. Because Catphan is the standard QA phantom for the on-board imager (OBI) device, we specifically recommend not using it for the HU calibration of CBCT.

  4. Systematic review of the effect of radiation dose on tumor control and morbidity in the treatment of prostate cancer by 3D-CRT

    SciTech Connect

    Tol-Geerdink, Julia J. van . E-mail: J.vanTol@rther.umcn.nl; Stalmeier, Peep F.M.; Pasker-de Jong, Pieternel C.M.; Huizenga, Henk; Lin, Emile N.J.T. van; Schimmel, Erik C.; Leer, Jan Willem; Daal, Willem A.J. van

    2006-02-01

    Purpose: A higher radiation dose is believed to result in a larger probability of tumor control and a higher risk of side effects. To make an evidence-based choice of dose, the relation between dose and outcome needs to be known. This study focuses on the dose-response relation for prostate cancer. Methods and Materials: A systematic review was carried out on the literature from 1990 to 2003. From the selected studies, the radiation dose, the associated 5-year survival, 5-year bNED (biochemical no evidence of disease), acute and late gastrointestinal (GI) and genitourinary (GU) morbidity Grade 2 or more, and sexual dysfunction were extracted. With logistic regression models, the relation between dose and outcome was described. Results: Thirty-eight studies met our criteria, describing 87 subgroups and involving up to 3000 patients per outcome measure. Between the (equivalent) dose of 70 and 80 Gy, various models estimated an increase in 5-year survival (ranging from 10% to 11%), 5-year bNED for low-risk patients (5-7%), late GI complications (12-16%), late GU complications (8-10%), and erectile dysfunction (19-24%). Only for the overall 5-year bNED, results were inconclusive (range, 0-18%). Conclusions: The data suggest a relationship between dose and outcome measures, including survival. However, the strength of these conclusions is limited by the sometimes small number of studies, the incompleteness of the data, and above all, the correlational nature of the data. Unambiguous proof for the dose-response relationships can, therefore, only be obtained by conducting randomized trials.

  5. Calibration of portal imaging devices for radiotherapy in-vivo dosimetry

    NASA Astrophysics Data System (ADS)

    Piermattei, Angelo; Cilla, Savino; Fidanzio, Andrea; Greco, Francesca; Sabatino, Domenico; Gargiulo, Laura; Azario, Luigi

    2010-11-01

    The complexity of radiotherapy techniques requires an accurate verification of the dose delivered to the patient during treatment. Recently, the present authors have developed an in patient dose reconstruction method with X-ray beams for 3D conformal radiotherapy. The procedure is based on correlation functions defined by the ratios of the transit signal measured by an electronic portal imaging device (EPID) to the mid-plane dose measured by calibrated ion chambers in a solid water phantom. The dosimetric characterization of aSi EPIDs in terms of signal stability, linearity and dependence on field dimension pointed out that these detectors are useful for the transit dosimetry of photon beams. However, the aSi EPIDs manufactured by Varian, Elekta and Siemens for their linacs are at present used for the visual inspection of the patient's set-up, and their use as transit dosimeters needs a special calibration that requires an effort for every beam. The aim of this paper has been the determination of a generalized EPID calibration that can be used by linacs of different manufacturers equipped with aSi EPIDs. The transit dosimetry method here proposed could supply for every linac the reconstruction in real time of the isocenter dose in patients with a tolerance level ranging between ±4% and ±6% depending on the treatment type and body district.

  6. Proton radiotherapy for orbital rhabdomyosarcoma: Clinical outcome and a dosimetric comparison with photons

    SciTech Connect

    Yock, Torunn . E-mail: tyock@partners.org; Schneider, Robert C.; Friedmann, Alison; Adams, Judith C.; Fullerton, Barbara; Tarbell, Nancy

    2005-11-15

    Background: Over 85% of pediatric orbital rhabdomyosarcoma (RMS) are cured with combined chemotherapy and radiation. However, the late effects of photon radiation compromise function and cosmetic outcome. Proton radiation can provide excellent tumor dose distributions while sparing normal tissues better than photon irradiation. Methods and Materials: Conformal 3D photon and proton radiotherapy plans were generated for children treated with proton irradiation for orbital RMS at Massachusetts General Hospital. Dose-volume histograms (90%, 50%, 10%) were generated and compared for important orbital and central nervous system structures. Average percentages of total dose prescribed were calculated based on the 3 dose-volume histogram levels for normal orbital structures for both the proton and photon plans. The percent of normal tissue spared by using protons was calculated. Results: Seven children were treated for orbital rhabdomyosarcoma with proton irradiation and standard chemotherapy. The median follow-up is 6.3 years (range, 3.5-9.7 years). Local and distant controls compare favorably to those in other published accounts. There was an advantage in limiting the dose to the brain, pituitary, hypothalamus, temporal lobes, and ipsilateral and contralateral orbital structures. Tumor size and location affect the degree of sparing of normal structures. Conclusions: Fractionated proton radiotherapy is superior to 3D conformal photon radiation in the treatment of orbital RMS. Proton therapy maintains excellent tumor coverage while reducing the radiation dose to adjacent normal structures. Proton radiation therapy minimizes long-term side effects.

  7. [Radiotherapy of bone metastases].

    PubMed

    Thureau, S; Vieillard, M-H; Supiot, S; Lagrange, J-L

    2016-09-01

    Radiotherapy plays a major role in palliative treatment of bone metastases. Recent developments of stereotactic radiotherapy and intensity modulated radiation therapy give the possibility to treat oligometastatic diseases. The objective of this paper is to report indications and treatment modalities of radiotherapy in these situations.

  8. Monte Carlo Simulations for Dosimetry in Prostate Radiotherapy with Different Intravesical Volumes and Planning Target Volume Margins

    PubMed Central

    Lv, Wei; Yu, Dong; He, Hengda; Liu, Qian

    2016-01-01

    In prostate radiotherapy, the influence of bladder volume variation on the dose absorbed by the target volume and organs at risk is significant and difficult to predict. In addition, the resolution of a typical medical image is insufficient for visualizing the bladder wall, which makes it more difficult to precisely evaluate the dose to the bladder wall. This simulation study aimed to quantitatively investigate the relationship between the dose received by organs at risk and the intravesical volume in prostate radiotherapy. The high-resolution Visible Chinese Human phantom and the finite element method were used to construct 10 pelvic models with specific intravesical volumes ranging from 100 ml to 700 ml to represent bladders of patients with different bladder filling capacities during radiotherapy. This series of models was utilized in six-field coplanar 3D conformal radiotherapy simulations with different planning target volume (PTV) margins. Each organ’s absorbed dose was calculated using the Monte Carlo method. The obtained bladder wall displacements during bladder filling were consistent with reported clinical measurements. The radiotherapy simulation revealed a linear relationship between the dose to non-targeted organs and the intravesical volume and indicated that a 10-mm PTV margin for a large bladder and a 5-mm PTV margin for a small bladder reduce the effective dose to the bladder wall to similar degrees. However, larger bladders were associated with evident protection of the intestines. Detailed dosimetry results can be used by radiation oncologists to create more accurate, individual water preload protocols according to the patient’s anatomy and bladder capacity. PMID:27441944

  9. Intensity-Modulated vs. Conformal Radiotherapy of Parotid Gland Tumors: Potential Impact on Hearing Loss

    SciTech Connect

    Lamers-Kuijper, E. Schwarz, M.; Rasch, C.; Mijnheer, B.

    2007-01-01

    In 3-dimensional (3D) conformal radiotherapy of parotid gland tumors, little effort is made to avoid the auditory system or the oral cavity. Damage may occur when the ear is located inside the treatment field. The purpose of this study was to design and evaluate an intensity-modulation radiotherapy (IMRT) class solution, and to compare this technique to a 3D conformal approach with respect to hearing loss. Twenty patients with parotid gland cancer were retrospectively planned with 2 different techniques using the original planning target volume (PTV). First, a conventional technique using a wedged beam pair was applied, yielding a dose distribution conformal to the shape of the PTV. Next, an IMRT technique using a fluence map optimization with predefined constraints was designed. A dose of 66 Gy in the PTV was given at the International Commission on Radiation Units and Measures (ICRU) dose prescription point. Dose-volume histograms of the PTV and organs at risk (OARs), such as auditory system, oral cavity, and spinal cord, were compared. The dose in the OARs was lower in the IMRT plans. The mean volume of the middle ear receiving a dose higher than 50 Gy decreased from 66.5% to 33.4%. The mean dose in the oral cavity decreased from 19.4 Gy to 16.6 Gy. The auditory system can be spared if the distance between the inner ear and the PTV is 0.6 cm or larger, and if the overlap between the middle ear and the PTV is smaller than 10%. The maximum dose in the spinal cord was below 40 Gy in all treatment plans. The mean volume of the PTV receiving less than 95% of the prescribed dose increased in the IMRT plan slightly from 3.3% to 4.3 % (p = 0.01). The mean volume receiving more than 107% increased from 0.9% to 2.5% (p = 0.02). It can be concluded that the auditory system, as well as the oral cavity, can be spared with IMRT, but at the cost of a slightly larger dose inhomogeneity in the PTV. The IMRT technique can therefore, in most cases, be recommended as the treatment

  10. [Radiotherapy of hypopharynx cancers].

    PubMed

    Pointreau, Y; Lafond, C; Trémolières, P; Legouté, F; Servagi-Vernat, S; Giraud, P; Maingon, P; Calais, G; Lapeyre, M

    2016-09-01

    The intensity-modulated radiotherapy is the gold standard in the treatment of hypopharynx cancers. Early T1 and T2 tumours could be treated by exclusive radiotherapy or surgery. For tumours requiring total pharyngolaryngectomy (T2 or T3), induction chemotherapy followed by exclusive radiotherapy or concurrent chemoradiotherapy are possible. For T4 tumours, surgery must be proposed. The treatment of lymph nodes is based on the initial treatment of the primary tumour. In non-surgical procedure, in case of sequential radiotherapy, curative dose is 70Gy and prophylactic dose is 50Gy. An integrated simultaneous boost radiotherapy is allowed (70Gy in 2Gy per fraction and 56Gy in 1.8Gy per fraction or 70Gy in 2.12Gy per fraction). Postoperatively, radiotherapy is used for locally advanced cancers with dose levels based on pathologic criteria (66Gy for R1 resection, 50 to 54Gy for complete resection). Volume delineation is based on guidelines.

  11. Heavy-ion radiotherapy

    NASA Astrophysics Data System (ADS)

    Kanai, Tatsuaki

    2000-11-01

    Heavy-ion radiotherapy using high-energy carbon beams has been performed at the National Institute of Radiological Sciences, Japan. The physical frame works for heavy-ion radiotherapy are established using physical understandings of radiation physics. In order to increase the accuracy of heavy-ion radiotherapy, many physical problems should be solved. Unsolved problems, such as the depth dose distributions, range of heavy-ion in patients and heavy-ion dosimetry in the radiation therapy, are discussed. .

  12. Stereotactic radiotherapy for malignancies involving the trigeminal and facial nerves.

    PubMed

    Cuneo, K C; Zagar, T M; Brizel, D M; Yoo, D S; Hoang, J K; Chang, Z; Wang, Z; Yin, F F; Das, S K; Green, S; Ready, N; Bhatti, M T; Kaylie, D M; Becker, A; Sampson, J H; Kirkpatrick, J P

    2012-06-01

    Involvement of a cranial nerve caries a poor prognosis for many malignancies. Recurrent or residual disease in the trigeminal or facial nerve after primary therapy poses a challenge due to the location of the nerve in the skull base, the proximity to the brain, brainstem, cavernous sinus, and optic apparatus and the resulting complex geometry. Surgical resection caries a high risk of morbidity and is often not an option for these patients. Stereotactic radiosurgery and radiotherapy are potential treatment options for patients with cancer involving the trigeminal or facial nerve. These techniques can deliver high doses of radiation to complex volumes while sparing adjacent critical structures. In the current study, seven cases of cancer involving the trigeminal or facial nerve are presented. These patients had unresectable recurrent or residual disease after definitive local therapy. Each patient was treated with stereotactic radiation therapy using a linear accelerator based system. A multidisciplinary approach including neuroradiology and surgical oncology was used to delineate target volumes. Treatment was well tolerated with no acute grade 3 or higher toxicity. One patient who was reirradiated experienced cerebral radionecrosis with mild symptoms. Four of the seven patients treated had no evidence of disease after a median follow up of 12 months (range 2-24 months). A dosimetric analysis was performed to compare intensity modulated fractionated stereotactic radiation therapy (IM-FSRT) to a 3D conformal technique. The dose to 90% (D90) of the brainstem was lower with the IM-FSRT plan by a mean of 13.5 Gy. The D95 to the ipsilateral optic nerve was also reduced with IM-FSRT by 12.2 Gy and the D95 for the optic chiasm was lower with FSRT by 16.3 Gy. Treatment of malignancies involving a cranial nerve requires a multidisciplinary approach. Use of an IM-FSRT technique with a micro-multileaf collimator resulted in a lower dose to the brainstem, optic nerves and chiasm

  13. [Radiotherapy of oropharynx carcinoma].

    PubMed

    Servagi Vernat, S; Tochet, F; Vieillevigne, L; Pointreau, Y; Maingon, P; Giraud, P

    2016-09-01

    Indication, doses, technique of radiotherapy and concomitant chemotherapy for oropharynx carcinoma are presented. The recommendations for delineation of the target volumes and organs at risk are detailed.

  14. Evaluating changes in tumor volume using magnetic resonance imaging during the course of radiotherapy treatment of high-grade gliomas: Implications for conformal dose-escalation studies

    SciTech Connect

    Tsien, Christina . E-mail: ctsien@umich.edu; Gomez-Hassan, Diana; Haken, Randall K. ten; Tatro, Daniel C.; Junck, L.; Chenevert, T.L.; Lawrence, T.

    2005-06-01

    Objective: To determine whether changes in tumor volume occur during the course of conformal 3D radiotherapy of high-grade gliomas by use of magnetic resonance imaging (MRI) during treatment and whether these changes had an impact on tumor coverage. Methods and Materials: Between December 2000 and January 2004, 21 patients with WHO Grades 3 to 4 supratentorial malignant gliomas treated with 3D conformal radiotherapy (median dose, 70 Gy) were enrolled in a prospective clinical study. All patients underwent T1-weighted contrast-enhancing and T2-weighted and fluid-attenuated inversion recovery (FLAIR) imaging at approximately 1 to 2 weeks before radiotherapy, during radiotherapy (Weeks 1 and 3), and at routine intervals thereafter. All MRI scans were coregistered to the treatment-planning CT. Gross tumor volume (GTV Pre-Rx) was defined from a postoperative T1-weighted contrast-enhancing MRI performed 1 to 2 weeks before start of radiotherapy. A second GTV (GTV Week 3) was defined by use of an MRI performed during Week 3 of radiotherapy. A uniform 0.5 cm expansion of the respective GTV, PTV (Pre-Rx), and PTV (Week 3) was applied to the final boost plan. Dose-volume histograms (DVH) were used to analyze any potential adverse changes in tumor coverage based on Week 3 MRI. Results: All MRI scans were reviewed independently by a neuroradiologist (DGH). Two patients were noted to have multifocal disease at presentation and were excluded from analysis. In 19 cases, changes in the GTV based on MRI at Week 3 during radiotherapy were as follows: 2 cases had an objective decrease in GTV ({>=}50%); 12 cases revealed a slight decrease in the rim enhancement or changes in cystic appearance of the GTV; 2 cases showed no change in GTV; and 3 cases demonstrated an increase in tumor volume. Both cases with objective decreases in GTV during treatment were Grade 3 tumors. No cases of tumor progression were noted in Grade 3 tumors during treatment. In comparison, three of 12 Grade 4

  15. [Radiotherapy of skin cancers].

    PubMed

    Hennequin, C; Rio, E; Mahé, M-A

    2016-09-01

    The indications of radiotherapy for skin cancers are not clearly defined because of the lack of randomised trials or prospective studies. For basal cell carcinomas, radiotherapy frequently offers a good local control, but a randomized trial showed that surgery is more efficient and less toxic. Indications of radiotherapy are contra-indications of surgery for patients older than 60, non-sclerodermiform histology and occurring in non-sensitive areas. Adjuvant radiotherapy could be proposed to squamous cell carcinomas, in case of poor prognostic factors. Dose of 60 to 70Gy are usually required, and must be modulated to the size of the lesions. Adjuvant radiotherapy seems beneficial for desmoplastic melanomas but not for the other histological types. Prophylactic nodal irradiation (45 to 50Gy), for locally advanced tumours (massive nodal involvement), decreases the locoregional failure rate but do not increase survival. Adjuvant radiotherapy (50 to 56Gy) for Merckel cell carcinomas increases also the local control rate, as demonstrated by meta-analysis and a large epidemiological study. Nodal areas must be included, if there is no surgical exploration (sentinel lymph node dissection). Kaposi sarcomas are radiosensitive and could be treated with relatively low doses (24 to 30Gy). Also, cutaneous lymphomas are good indications for radiotherapy: B lymphomas are electively treated with limited fields. The role of total skin electron therapy for T-lymphomas is still discussed; but palliative radiotherapy is very efficient in case of cutaneous nodules.

  16. The Degree of Lipiodol Accumulation Can Be an Indicator of Successful Treatment for Unresectable Hepatocellular Carcinoma (HCC) Patients - in the Case of Transcatheter Arterial Chemoembolization (TACE) and External Beam Radiotherapy (EBRT)

    PubMed Central

    Yang, Ping; Zeng, Zhao-Chong; Wang, Bin-Liang; Zhang, Jian-Ying; Fan, Jia; Zhou, Jian; Hu, Yong

    2016-01-01

    Purpose: Transcatheter arterial chemoembolization (TACE) in combination with external beam radiotherapy (EBRT) results in improved survival due to better local control in patients with unresectable hepatocellular carcinoma (HCC). The purpose of this study was to investigate lipiodol accumulation, as it reflects tumor burden and is a potential prognostic factor, in HCC patients treated with TACE/EBRT. Methods and Materials: We retrospectively studied 147 patients with unresectable HCC treated with TACE and EBRT. Clinical features, adverse reactions, and prognostic factors were analyzed. All patients were treated with TACE 1-6 times in combination with EBRT (44-66 Gy) in dose of 2 Gy/fraction given once a day five times a week. Tumor status and laboratory findings were followed. The degree of lipiodol accumulation was assessed by computed tomography before EBRT, and was categorized as either complete/intense or low/moderate. Results: The response rate of tumor size after EBRT was 68.2%, median survival was 23.1 months, and overall survival rates were 86.6%, 49.2%, and 28.2% at 1, 2, and 3 years, respectively. Univariate analysis showed that lower hemoglobin levels, higher alkaline phosphatase levels, Child-Pugh B, negative alpha-fetoprotein (AFP) response after EBRT, poor treatment response after EBRT, tumor diameter >10 cm, and poor lipiodol accumulation were unfavorable prognostic factors. On multivariate analysis, higher hemoglobin levels, Child-Pugh A, decreased AFP levels after treatment, Helical Tomotherapy (HT) and intense lipiodol accumulation after TACE were significant favorable predictors. Conclusions: The degree of lipiodol accumulation before EBRT is a prognostic factor in patients with unresectable HCC. Increased AFP levels after EBRT are always associated with poor survival. HT is recommended as a potentially better EBRT modality than three-dimensional conformal radiation therapy (3D-CRT). PMID:27471557

  17. [Prostate cancer external beam radiotherapy].

    PubMed

    de Crevoisier, R; Pommier, P; Latorzeff, I; Chapet, O; Chauvet, B; Hennequin, C

    2016-09-01

    The prostate external beam radiotherapy techniques are described, when irradiating the prostate or after prostatectomy, with and without pelvic lymph nodes. The following parts are presented: indications of radiotherapy, total dose and fractionation, planning CT image acquisition, volume of interest delineation (target volumes and organs at risk) and margins, Intensity modulated radiotherapy planning and corresponding dose-volume constraints, and finally Image guided radiotherapy.

  18. CONSIDERATION OF DOSE LIMITS FOR ORGANS AT RISK OF THORACIC RADIOTHERAPY: ATLAS FOR LUNG, PROXIMAL BRONCHIAL TREE, ESOPHAGUS, SPINAL CORD, RIBS, AND BRACHIAL PLEXUS

    PubMed Central

    Kong, Feng-Ming (Spring); Ritter, Timothy; Quint, Douglas J.; Senan, Suresh; Gaspar, Laurie E.; Komaki, Ritsuko U.; Hurkmans, Coen W.; Timmerman, Robert; Bezjak, Andrea; Bradley, Jeffrey D.; Movsas, Benjamin; Marsh, Lon; Okunieff, Paul; Choy, Hak; Curran, Walter J.

    2012-01-01

    Purpose To review the dose limits and standardize the three-dimenional (3D) radiographic definition for the organs at risk (OARs) for thoracic radiotherapy (RT), including the lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus. Methods and Materials The present study was performed by representatives from the Radiation Therapy Oncology Group, European Organization for Research and Treatment of Cancer, and Soutwestern Oncology Group lung cancer committees. The dosimetric constraints of major multicenter trials of 3D-conformal RT and stereotactic body RT were reviewed and the challenges of 3D delineation of these OARs described. Using knowledge of the human anatomy and 3D radiographic correlation, draft atlases were generated by a radiation oncologist, medical physicist, dosimetrist, and radiologist from the United States and reviewed by a radiation oncologist and medical physicist from Europe. The atlases were then critically reviewed, discussed, and edited by another 10 radiation oncologists. Results Three-dimensional descriptions of the lung, proximal bronchial tree, esophagus, spinal cord, ribs, and brachial plexus are presented. Two computed tomography atlases were developed: one for the middle and lower thoracic OARs (except for the heart) and one focusing on the brachial plexus for a patient positioned supine with their arms up for thoracic RT. The dosimetric limits of the key OARs are discussed. Conclusions We believe these atlases will allow us to define OARs with less variation and generate dosimetric data in a more consistent manner. This could help us study the effect of radiation on these OARs and guide high-quality clinical trials and individualized practice in 3D-conformal RT and stereotactic body RT. PMID:20934273

  19. Permuting input for more effective sampling of 3D conformer space

    NASA Astrophysics Data System (ADS)

    Carta, Giorgio; Onnis, Valeria; Knox, Andrew J. S.; Fayne, Darren; Lloyd, David G.

    2006-03-01

    SMILES strings and other classic 2D structural formats offer a convenient way to represent molecules as a simplistic connection table, with the inherent advantages of ease of handling and storage. In the context of virtual screening, chemical databases to be screened are often initially represented by canonicalised SMILES strings that can be filtered and pre-processed in a number of ways, resulting in molecules that occupy similar regions of chemical space to active compounds of a therapeutic target. A wide variety of software exists to convert molecules into SMILES format, namely, Mol2smi (Daylight Inc.), MOE (Chemical Computing Group) and Babel (Openeye Scientific Software). Depending on the algorithm employed, the atoms of a SMILES string defining a molecule can be ordered differently. Upon conversion to 3D coordinates they result in the production of ostensibly the same molecule. In this work we show how different permutations of a SMILES string can affect conformer generation, affecting reliability and repeatability of the results. Furthermore, we propose a novel procedure for the generation of conformers, taking advantage of the permutation of the input strings—both SMILES and other 2D formats, leading to more effective sampling of conformation space in output, and also implementing fingerprint and principal component analyses step to post process and visualise the results.

  20. Beyond Rotatable Bond Counts: Capturing 3D Conformational Flexibility in a Single Descriptor

    PubMed Central

    2016-01-01

    A new molecular descriptor, nConf20, based on chemical connectivity, is presented which captures the accessible conformational space of a molecule. Currently the best available two-dimensional descriptors for quantifying the flexibility of a particular molecule are the rotatable bond count (RBC) and the Kier flexibility index. We present a descriptor which captures this information by sampling the conformational space of a molecule using the RDKit conformer generator. Flexibility has previously been identified as a key feature in determining whether a molecule is likely to crystallize or not. For this application, nConf20 significantly outperforms previously reported single-variable classifiers and also assists rule-based analysis of black-box machine learning classification algorithms. PMID:28024401

  1. Beyond Rotatable Bond Counts: Capturing 3D Conformational Flexibility in a Single Descriptor.

    PubMed

    Wicker, Jerome G P; Cooper, Richard I

    2016-12-27

    A new molecular descriptor, nConf20, based on chemical connectivity, is presented which captures the accessible conformational space of a molecule. Currently the best available two-dimensional descriptors for quantifying the flexibility of a particular molecule are the rotatable bond count (RBC) and the Kier flexibility index. We present a descriptor which captures this information by sampling the conformational space of a molecule using the RDKit conformer generator. Flexibility has previously been identified as a key feature in determining whether a molecule is likely to crystallize or not. For this application, nConf20 significantly outperforms previously reported single-variable classifiers and also assists rule-based analysis of black-box machine learning classification algorithms.

  2. Treating benign optic nerve tumors with a 3-D conformal plan

    SciTech Connect

    Millunchick, Cheryl Hope

    2013-07-01

    A 68 year old male patient presented for radiation therapy for treatment of a benign tumor, a glioma of his left optic nerve. The radiation oncologist intended to prescribe 52.2 Gy to the planning target volume, while maintaining a maximum of 54 Gy to the optic nerves and the optic chiasm and a maximum of 40–45 Gy to the globes in order to minimize the possibility of damaging the optic system, which is especially important as this is a benign tumor. The dosimetrist devised a conformal non-coplanar three-dimensional plan with a slightly weighted forward planning component. This plan was created in approximately 15 minutes after the critical organs and the targets were delineated and resulted in an extremely conformal and homogenous plan, treating the target while sparing the nearby critical structures. This approach can also be extended to other tumors in the brain - benign or malignant.

  3. 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)

  4. Re-irradiation of spinal column metastases by IMRT: impact of setup errors on the dose distribution

    PubMed Central

    2013-01-01

    Background This study investigates the impact of an automated image guided patient setup correction on the dose distribution for ten patients with in-field IMRT re-irradiation of vertebral metastases. Methods 10 patients with spinal column metastases who had previously been treated with 3D-conformal radiotherapy (3D-CRT) were simulated to have an in-field recurrence. IMRT plans were generated for treatment of the vertebrae sparing the spinal cord. The dose distributions were compared for a patient setup based on skin marks only and a Cone Beam CT (CBCT) based setup with translational and rotational couch corrections using an automatic robotic image guided couch top (Elekta - HexaPOD™ IGuide® - system). The biological equivalent dose (BED) was calculated to evaluate and rank the effects of the automatic setup correction for the dose distribution of CTV and spinal cord. Results The mean absolute value (± standard deviation) over all patients and fractions of the translational error is 6.1 mm (±4 mm) and 2.7° (±1.1 mm) for the rotational error. The dose coverage of the 95% isodose for the CTV is considerable decreased for the uncorrected table setup. This is associated with an increasing of the spinal cord dose above the tolerance dose. Conclusions An automatic image guided table correction ensures the delivery of accurate dose distribution and reduces the risk of radiation induced myelopathy. PMID:24238332

  5. SU-E-T-221: Investigation of Lower Energy (< 6 MV) Photon Beams for Cancer Radiotherapy

    SciTech Connect

    Zhang, Y; Ming, X; Feng, Y; Zhou, L; Ahmad, M; Deng, J; Nguyen, K; Griffin, M

    2014-06-01

    Purpose: To study the potential applications of the lower energy (< 6MV) photon beams in the radiotherapeutic management of pediatric cancer and lung cancer patients. Methods: Photon beams of 2, 3, 4, 5 and 6MV were first simulated with EGS4/BEAM and then used for Monte-Carlo dose calculations. For four pediatric patients with abdominal and brain lesions, six 3D-conformal radiotherapy (3DCRT) plans were generated using single photon energy (2 to 6MV) or mixed energies (3 and 6MV). Furthermore, a virtual machine of 3 and 6MV was commissioned in a treatment planning system (TPS) based on Monte-Carlo simulated data. Three IMRT plans of a lung cancer patient were generated on this virtual machine. All plans were normalized to D95% of target dose for 6MV plan and then compared in terms of integral dose and OAR sparing. Results: For the four pediatric patients, the integral dose for the 2, 3, 4 and 5MV plans increased by 9%, 5%, 3.5%, 1.7%, respectively as compared to 6MV. Almost all OARs in the 2MV plan received more than 10% more doses than 6MV. Mixed energy 3DCRT plans were of the same quality as 6MV plans. For the lung IMRT plans, both the 3MV plan and the mixed beam plan showed better OAR sparing in comparison to 6MV plan. Specifically, the maximum and mean doses to the spinal cord in the mixed energy plan were lower by 21% and 16%, respectively. Conclusion: Single lower energy photon beam was found to be inferior to 6MV in the radiotherapy of pediatric patients and lung cancer patients when the integral doses and the doses to the OARs were considered. However, mixed energy plans combining low with high energy beams showed significant OAR sparing while maintaining the same PTV coverage. Investigation with more patient data is ongoing for further confirmation.

  6. [Radiotherapy of larynx cancers].

    PubMed

    Pointreau, Y; Lafond, C; Legouté, F; Trémolières, P; Servagi-Vernat, S; Giraud, P; Maingon, P; Calais, G; Lapeyre, M

    2016-09-01

    Intensity-modulated radiotherapy is the gold standard in the treatment of larynx cancers (except T1 glottic tumour). Early T1 and T2 tumours may be treated by exclusive radiation or surgery. For tumours requiring total laryngectomy (T2 or T3), induction chemotherapy followed by exclusive radiotherapy or concurrent chemoradiotherapy is possible. For T4 tumour, surgery must be proposed. The treatment of lymph nodes is based on the initial treatment of the primary tumour. In non-surgical procedure, in case of sequential radiotherapy, the curative dose is 70Gy and the prophylactic dose is 50Gy. An integrated simultaneous boost radiotherapy is allowed (70Gy in 2Gy per fraction and 56Gy in 1.8Gy per fraction or 70Gy in 2.12Gy per fraction). Postoperatively, radiotherapy is used in locally advanced cancer with dose levels based on pathologic criteria (66Gy for R1 resection, 50 to 54Gy for complete resection). Volume delineation was based on guidelines.

  7. [Radiotherapy for retroperitoneal sarcomas].

    PubMed

    Sargos, P; Stoeckle, E; Henriques de Figueiredo, B; Antoine, M; Delannes, M; Mervoyer, A; Kantor, G

    2016-10-01

    The management of retroperitoneal sarcoma can be very challenging, and the quality of initial treatment strategy appears to be a crucial prognostic factor. En bloc surgery is currently the standard of care for these rare tumours and perioperative treatments such as chemotherapy or radiotherapy have not been validated yet. However, local-regional relapse constitutes the most common disease course. While adjuvant radiotherapy is less and less common due to gastrointestinal toxicities, preoperative radiation therapy offers numerous advantages and is being evaluated as part of a national multicentre phase II study (TOMOREP trial) and is the subject of a European randomized phase III study (STRASS trial). The objective of this article is to present data on preoperative irradiation in terms of dose, volumes and optimal radiotherapy techniques for the treatment of this rare disease.

  8. [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.

  9. Radiotherapy for lung cancer

    SciTech Connect

    Bleehen, N.M.; Cox, J.D.

    1985-05-01

    The role of radiation therapy in the management of lung cancer was reviewed at a workshop held in Cambridge, England, in June 1984. It was concluded that there was a continuing role for radiation therapy in the primary management of small cell lung cancer, including the loco-regional treatment for patients with limited disease. Radical radiotherapy for patients with non-small cell carcinoma could be curative for a proportion of patients with limited disease. Careful planning and quality control was essential. Palliative radiotherapy provided useful treatment for many other patients. Other related aspects of treatment are also presented.

  10. Precision radiotherapy for brain tumors

    PubMed Central

    Yan, Ying; Guo, Zhanwen; Zhang, Haibo; Wang, Ning; Xu, Ying

    2012-01-01

    OBJECTIVE: Precision radiotherapy plays an important role in the management of brain tumors. This study aimed to identify global research trends in precision radiotherapy for brain tumors using a bibliometric analysis of the Web of Science. DATA RETRIEVAL: We performed a bibliometric analysis of data retrievals for precision radiotherapy for brain tumors containing the key words cerebral tumor, brain tumor, intensity-modulated radiotherapy, stereotactic body radiation therapy, stereotactic ablative radiotherapy, imaging-guided radiotherapy, dose-guided radiotherapy, stereotactic brachytherapy, and stereotactic radiotherapy using the Web of Science. SELECTION CRITERIA: Inclusion criteria: (a) peer-reviewed articles on precision radiotherapy for brain tumors which were published and indexed in the Web of Science; (b) type of articles: original research articles and reviews; (c) year of publication: 2002-2011. Exclusion criteria: (a) articles that required manual searching or telephone access; (b) Corrected papers or book chapters. MAIN OUTCOME MEASURES: (1) Annual publication output; (2) distribution according to country; (3) distribution according to institution; (4) top cited publications; (5) distribution according to journals; and (6) comparison of study results on precision radiotherapy for brain tumors. RESULTS: The stereotactic radiotherapy, intensity-modulated radiotherapy, and imaging-guided radiotherapy are three major methods of precision radiotherapy for brain tumors. There were 260 research articles addressing precision radiotherapy for brain tumors found within the Web of Science. The USA published the most papers on precision radiotherapy for brain tumors, followed by Germany and France. European Synchrotron Radiation Facility, German Cancer Research Center and Heidelberg University were the most prolific research institutes for publications on precision radiotherapy for brain tumors. Among the top 13 research institutes publishing in this field, seven

  11. Development and evaluation of a clinical model for lung cancer patients using stereotactic body radiotherapy (SBRT) within a knowledge-based algorithm for treatment planning.

    PubMed

    Snyder, Karen Chin; Kim, Jinkoo; Reding, Anne; Fraser, Corey; Gordon, James; Ajlouni, Munther; Movsas, Benjamin; Chetty, Indrin J

    2016-11-08

    The purpose of this study was to describe the development of a clinical model for lung cancer patients treated with stereotactic body radiotherapy (SBRT) within a knowledge-based algorithm for treatment planning, and to evaluate the model performance and applicability to different planning techniques, tumor locations, and beam arrangements. 105 SBRT plans for lung cancer patients previously treated at our institution were included in the development of the knowledge-based model (KBM). The KBM was trained with a combination of IMRT, VMAT, and 3D CRT techniques. Model performance was validated with 25 cases, for both IMRT and VMAT. The full KBM encompassed lesions located centrally vs. peripherally (43:62), upper vs. lower (62:43), and anterior vs. posterior (60:45). Four separate sub-KBMs were created based on tumor location. Results were compared with the full KBM to evaluate its robustness. Beam templates were used in conjunction with the optimizer to evaluate the model's ability to handle suboptimal beam placements. Dose differences to organs-at-risk (OAR) were evaluated between the plans gener-ated by each KBM. Knowledge-based plans (KBPs) were comparable to clinical plans with respect to target conformity and OAR doses. The KBPs resulted in a lower maximum spinal cord dose by 1.0 ± 1.6 Gy compared to clinical plans, p = 0.007. Sub-KBMs split according to tumor location did not produce significantly better DVH estimates compared to the full KBM. For central lesions, compared to the full KBM, the peripheral sub-KBM resulted in lower dose to 0.035 cc and 5 cc of the esophagus, both by 0.4Gy ± 0.8Gy, p = 0.025. For all lesions, compared to the full KBM, the posterior sub-KBM resulted in higher dose to 0.035 cc, 0.35 cc, and 1.2 cc of the spinal cord by 0.2 ± 0.4Gy, p = 0.01. Plans using template beam arrangements met target and OAR criteria, with an increase noted in maximum heart dose (1.2 ± 2.2Gy, p = 0.01) and GI (0.2 ± 0.4, p = 0.01) for the nine

  12. SU-E-T-562: Motion Tracking Optimization for Conformal Arc Radiotherapy Plans: A QUASAR Phantom Based Study

    SciTech Connect

    Xu, Z; Wang, I; Yao, R; Podgorsak, M

    2015-06-15

    Purpose: This study is to use plan parameters optimization (Dose rate, collimator angle, couch angle, initial starting phase) to improve the performance of conformal arc radiotherapy plans with motion tracking by increasing the plan performance score (PPS). Methods: Two types of 3D conformal arc plans were created based on QUASAR respiratory motion phantom with spherical and cylindrical targets. Sinusoidal model was applied to the MLC leaves to generate motion tracking plans. A MATLAB program was developed to calculate PPS of each plan (ranges from 0–1) and optimize plan parameters. We first selected the dose rate for motion tracking plans and then used simulated annealing algorithm to search for the combination of the other parameters that resulted in the plan of the maximal PPS. The optimized motion tracking plan was delivered by Varian Truebeam Linac. In-room cameras and stopwatch were used for starting phase selection and synchronization between phantom motion and plan delivery. Gaf-EBT2 dosimetry films were used to measure the dose delivered to the target in QUASAR phantom. Dose profiles and Truebeam trajectory log files were used for plan delivery performance evaluation. Results: For spherical target, the maximal PPS (PPSsph) of the optimized plan was 0.79: (Dose rate: 500MU/min, Collimator: 90°, Couch: +10°, starting phase: 0.83π). For cylindrical target, the maximal PPScyl was 0.75 (Dose rate: 300MU/min, Collimator: 87°, starting phase: 0.97π) with couch at 0°. Differences of dose profiles between motion tracking plans (with the maximal and the minimal PPS) and 3D conformal plans were as follows: PPSsph=0.79: %ΔFWHM: 8.9%, %Dmax: 3.1%; PPSsph=0.52: %ΔFWHM: 10.4%, %Dmax: 6.1%. PPScyl=0.75: %ΔFWHM: 4.7%, %Dmax: 3.6%; PPScyl=0.42: %ΔFWHM: 12.5%, %Dmax: 9.6%. Conclusion: By achieving high plan performance score through parameters optimization, we can improve target dose conformity of motion tracking plan by decreasing total MLC leaf travel distance

  13. Impact of the radiotherapy technique on the correlation between dose-volume histograms of the bladder wall defined on MRI imaging and dose-volume/surface histograms in prostate cancer patients

    NASA Astrophysics Data System (ADS)

    Maggio, Angelo; Carillo, Viviana; Cozzarini, Cesare; Perna, Lucia; Rancati, Tiziana; Valdagni, Riccardo; Gabriele, Pietro; Fiorino, Claudio

    2013-04-01

    The aim of this study was to evaluate the correlation between the ‘true’ absolute and relative dose-volume histograms (DVHs) of the bladder wall, dose-wall histogram (DWH) defined on MRI imaging and other surrogates of bladder dosimetry in prostate cancer patients, planned both with 3D-conformal and intensity-modulated radiation therapy (IMRT) techniques. For 17 prostate cancer patients, previously treated with radical intent, CT and MRI scans were acquired and matched. The contours of bladder walls were drawn by using MRI images. External bladder surfaces were then used to generate artificial bladder walls by performing automatic contractions of 5, 7 and 10 mm. For each patient a 3D conformal radiotherapy (3DCRT) and an IMRT treatment plan was generated with a prescription dose of 77.4 Gy (1.8 Gy/fr) and DVH of the whole bladder of the artificial walls (DVH-5/10) and dose-surface histograms (DSHs) were calculated and compared against the DWH in absolute and relative value, for both treatment planning techniques. A specific software (VODCA v. 4.4.0, MSS Inc.) was used for calculating the dose-volume/surface histogram. Correlation was quantified for selected dose-volume/surface parameters by the Spearman correlation coefficient. The agreement between %DWH and DVH5, DVH7 and DVH10 was found to be very good (maximum average deviations below 2%, SD < 5%): DVH5 showed the best agreement. The correlation was slightly better for absolute (R = 0.80-0.94) compared to relative (R = 0.66-0.92) histograms. The DSH was also found to be highly correlated with the DWH, although slightly higher deviations were generally found. The DVH was not a good surrogate of the DWH (R < 0.7 for most of parameters). When comparing the two treatment techniques, more pronounced differences between relative histograms were seen for IMRT with respect to 3DCRT (p < 0.0001).

  14. [Radiotherapy for Graves' ophthalmopathy].

    PubMed

    Kuhnt, T; Müller, A C; Janich, M; Gerlach, R; Hädecke, J; Duncker, G I W; Dunst, J

    2004-11-01

    Graves' ophthalmopathy (GO) is the most frequent extrathyroidal manifestation of Graves' disease, an autoimmune disorder of the thyroid, whereas the precise pathogenesis still remains unclear. In Hashimoto's thyroiditis the occurrence of proptosis is an extremely rare event. The therapy for middle and severe courses of GO shows in partly disappointing results, although several therapy modalities are possible (glucocorticoid therapy, radiotherapy, antithyroid drug treatment, surgery). All these therapies lead in only 40 - 70 % to an improvement of the pathogenic symptoms. An intensive interdisciplinary cooperation is necessary to satisfy the requirements for the treatment of Graves' ophthalmopathy. As a consequence of the very different results of the few of clinical studies that were accomplished with reference to this topic, treatment by radiotherapy in the management of the disease is presently controversially discussed. In the German-speaking countries the radiotherapy is, however, firmly established as a therapy option in the treatment of the moderate disease classes (class 2-5 according to NO SPECS), especially if diplopia is present. This article describes the sequences, dosages and fractionation schemes as well as the risks and side effects of the radiotherapy. Altogether, radiotherapy is assessed as an effective and sure method. The administration of glucocorticoids can take place before the beginning of or during the radiotherapy. For the success of treatment the correct selection of patients who may possibly profit from a radiotherapy is absolutely essential. By realising that GO proceeds normally over a period of 2-5 years, which is followed by a period of fibrotic alteration, the application of the radiotherapy in the early, active phase is indispensable. A precise explanation for the effects of radiotherapy in treatment of the GO does not exist at present. The determination of the most effective irradiation doses was made from retrospectively evaluated

  15. Radiotherapy for bone pain.

    PubMed Central

    Needham, P R; Mithal, N P; Hoskin, P J

    1994-01-01

    Painful bone metastases are a common problem for cancer patients. Although current evidence supports the use of a single fraction of radiotherapy as the treatment of choice, many radiotherapists, for a variety of reasons, continue to use fractionated regimens. Over one six month period 105 patients received external beam irradiation for painful bone metastases at the Royal London Hospital (RLH). Thirty-one per cent of the patients were aged 70 or over. The treatment of 97 of these patients was assessed. They had a total of 280 sites treated over the course of their disease. Fifty-nine per cent of sites treated received a fractionated course of radiotherapy. Site significantly influenced fractionation. Overall response rates of 82% were achieved. Fractionation did not appear to influence this. Ten patients received large field irradiation. Fifteen patients had five or more sites irradiated, of whom only one received hemibody irradiation. PMID:7523672

  16. Melanoma: Last call for radiotherapy.

    PubMed

    Espenel, Sophie; Vallard, Alexis; Rancoule, Chloé; Garcia, Max-Adrien; Guy, Jean-Baptiste; Chargari, Cyrus; Deutsch, Eric; Magné, Nicolas

    2017-02-01

    Melanoma is traditionally considered to be a radioresistant tumor. However, radiotherapy and immunotherapy latest developments might upset this radiobiological dogma. Stereotactic radiotherapy allows high dose per fraction delivery, with high dose rate. More DNA lethal damages, less sublethal damages reparation, endothelial cell apoptosis, and finally clonogenic cell dysfunction are produced, resulting in improved local control. Radiotherapy can also enhance immune responses, inducing neoantigens formation, tumor antigen presentation, and cytokines release. A synergic effect of radiotherapy with immunotherapy is expected, and might lead to abscopal effects. If hadrontherapy biological properties seem able to suppress hypoxia-induced radioresistance and increase biological efficacy, ballistic advantages over photon radiations might also improve radiotherapy outcomes on usually poor prognosis locations. The present review addresses biological and clinical effects of high fraction dose, bystander effect, abscopal effect, and hadrontherapy features in melanoma. Clinical trials results are warranted to establish indications of innovative radiotherapy in melanoma.

  17. Accident prevention in radiotherapy

    PubMed Central

    Holmberg, O

    2007-01-01

    In order to prevent accidents in radiotherapy, it is important to learn from accidents that have occurred previously. Lessons learned from a number of accidents are summarised and underlying patterns are looked for in this paper. Accidents can be prevented by applying several safety layers of preventive actions. Categories of these preventive actions are discussed together with specific actions belonging to each category of safety layer. PMID:21614274

  18. [Radiotherapy of bladder cancer].

    PubMed

    Riou, O; Chauvet, B; Lagrange, J-L; Martin, P; Llacer Moscardo, C; Charissoux, M; Lauche, O; Aillères, N; Fenoglietto, P; Azria, D

    2016-09-01

    Surgery (radical cystectomy) is the standard treatment of muscle-invasive bladder cancer. Radiochemotherapy has risen as an alternative treatment option to surgery as part as organ-sparing combined modality treatment or for patients unfit for surgery. Radiochemotherapy achieves 5-year bladder intact survival of 40 to 65% and 5-year overall survival of 40 to 50% with excellent quality of life. This article introduces the French recommendations for radiotherapy of bladder cancer: indications, exams, technique, dosimetry, delivery and image guidance.

  19. Radiotherapy DICOM packet sniffing.

    PubMed

    Ackerly, T; Gesoand, M; Smith, R

    2008-09-01

    The Digital Imaging and Communications in Medicine (DICOM) standard is meant to allow communication of medical images between equipment provided by different vendors, but when two applications do not interact correctly in a multi-vendor environment it is often first necessary to demonstrate non-compliance of either the sender or the receiver before a resolution to the problem can be progressed. Sometimes the only way to do this is to monitor the network communication between the two applications to find out which one is not complying with the DICOM standard. Packet sniffing is a technique of network traffic analysis by passive observation of all information transiting a point on the network, regardless of the specified sender or receiver. DICOM packet sniffing traps and interprets the network communication between two DICOM applications to determine which is non compliant. This is illustrated with reference to three examples, a radiotherapy planning system unable to receive CT data from a particular CT scanner, a radiotherapy simulator unable to print correctly on a DICOM printer, and a PACS unable to respond when queried about what images it has in its archive by a radiotherapy treatment planning system. Additionally in this work it has been proven that it is feasible to extract DICOM images from the intercepted network data. This process can be applied to determine the cause of a DICOM image being rendered differently by the sender and the receiver.

  20. Imaging in radiotherapy.

    PubMed

    Van den Berge, D L; De Ridder, M; Storme, G A

    2000-10-01

    Radiotherapy, more then any other treatment modality, relies heavily and often exclusively on medical imaging to determine the extent of disease and the spatial relation between target region and neighbouring healthy tissues. Radically new approaches to radiation delivery are inspired on CT scanning and treat patients in a slice-by-slice fashion using intensity modulated megavoltage fan beams. For quality assurance of complex 3-D dose distributions, MR based 3-D verificative dosimetry on irradiated phantoms has been described. As treatment delivery becomes increasingly refined, the need for accurate target definition increases as well and sophisticated imaging tools like image fusion and 3-D reconstruction are routinely used for treatment planning. While in the past patients were positioned on the treatment machines based exclusively on surface topography and the well-known skin marks, such approach is no longer sufficient for high-accuracy radiotherapy and special imaging tools like on-line portal imaging are used to verify and correct target positioning. Much of these applications rely on digital image processing, transmission and storage, and the development of standards, like DICOM and PACS have greatly contributed to these applications. Digital imaging plays an increasing role in many areas in radiotherapy and has been fundamental in new developments that have demonstrated impact on patient care.

  1. The adaptation of megavoltage cone beam CT for use in standard radiotherapy treatment planning.

    PubMed

    Thomas, T Hannah Mary; Devakumar, D; Purnima, S; Ravindran, B Paul

    2009-04-07

    Potential areas where megavoltage computed tomography (MVCT) could be used are second- and third-phase treatment planning in 3D conformal radiotherapy and IMRT, adaptive radiation therapy, single fraction palliative treatment and for the treatment of patients with metal prostheses. A feasibility study was done on using MV cone beam CT (CBCT) images generated by proprietary 3D reconstruction software based on the FDK algorithm for megavoltage treatment planning. The reconstructed images were converted to a DICOM file set. The pixel values of megavoltage cone beam computed tomography (MV CBCT) were rescaled to those of kV CT for use with a treatment planning system. A calibration phantom was designed and developed for verification of geometric accuracy and CT number calibration. The distance measured between two marker points on the CBCT image and the physical dimension on the phantom were in good agreement. Point dose verification for a 10 cm x 10 cm beam at a gantry angle of 0 degrees and SAD of 100 cm were performed for a 6 MV beam for both kV and MV CBCT images. The point doses were found to vary between +/-6.1% of the dose calculated from the kV CT image. The isodose curves for 6 MV for both kV CT and MV CBCT images were within 2% and 3 mm distance-to-agreement. A plan with three beams was performed on MV CBCT, simulating a treatment plan for cancer of the pituitary. The distribution obtained was compared with those corresponding to that obtained using the kV CT. This study has shown that treatment planning with MV cone beam CT images is feasible.

  2. The adaptation of megavoltage cone beam CT for use in standard radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Thomas, T. Hannah Mary; Devakumar, D.; Purnima, S.; Ravindran, B. Paul

    2009-04-01

    Potential areas where megavoltage computed tomography (MVCT) could be used are second- and third-phase treatment planning in 3D conformal radiotherapy and IMRT, adaptive radiation therapy, single fraction palliative treatment and for the treatment of patients with metal prostheses. A feasibility study was done on using MV cone beam CT (CBCT) images generated by proprietary 3D reconstruction software based on the FDK algorithm for megavoltage treatment planning. The reconstructed images were converted to a DICOM file set. The pixel values of megavoltage cone beam computed tomography (MV CBCT) were rescaled to those of kV CT for use with a treatment planning system. A calibration phantom was designed and developed for verification of geometric accuracy and CT number calibration. The distance measured between two marker points on the CBCT image and the physical dimension on the phantom were in good agreement. Point dose verification for a 10 cm × 10 cm beam at a gantry angle of 0° and SAD of 100 cm were performed for a 6 MV beam for both kV and MV CBCT images. The point doses were found to vary between ±6.1% of the dose calculated from the kV CT image. The isodose curves for 6 MV for both kV CT and MV CBCT images were within 2% and 3 mm distance-to-agreement. A plan with three beams was performed on MV CBCT, simulating a treatment plan for cancer of the pituitary. The distribution obtained was compared with those corresponding to that obtained using the kV CT. This study has shown that treatment planning with MV cone beam CT images is feasible.

  3. [Radiotherapy for primary lung carcinoma].

    PubMed

    Giraud, P; Lacornerie, T; Mornex, F

    2016-09-01

    Indication, doses, technique of radiotherapy and concomitant chemotherapy, for primary lung carcinoma are presented. The recommendations for delineation of the target volumes and organs at risk are detailed.

  4. Particle radiotherapy for prostate cancer.

    PubMed

    Shioyama, Yoshiyuki; Tsuji, Hiroshi; Suefuji, Hiroaki; Sinoto, Makoto; Matsunobu, Akira; Toyama, Shingo; Nakamura, Katsumasa; Kudo, Sho

    2015-01-01

    Recent advances in external beam radiotherapy have allowed us to deliver higher doses to the tumors while decreasing doses to the surrounding tissues. Dose escalation using high-precision radiotherapy has improved the treatment outcomes of prostate cancer. Intensity-modulated radiation therapy has been widely used throughout the world as the most advanced form of photon radiotherapy. In contrast, particle radiotherapy has also been under development, and has been used as an effective and non-invasive radiation modality for prostate and other cancers. Among the particles used in such treatments, protons and carbon ions have the physical advantage that the dose can be focused on the tumor with only minimal exposure of the surrounding normal tissues. Furthermore, carbon ions also have radiobiological advantages that include higher killing effects on intrinsic radio-resistant tumors, hypoxic tumor cells and tumor cells in the G0 or S phase. However, the degree of clinical benefit derived from these theoretical advantages in the treatment of prostate cancer has not been adequately determined. The present article reviews the available literature on the use of particle radiotherapy for prostate cancer as well as the literature on the physical and radiobiological properties of this treatment, and discusses the role and the relative merits of particle radiotherapy compared with current photon-based radiotherapy, with a focus on proton beam therapy and carbon ion radiotherapy.

  5. Bystander effects and radiotherapy.

    PubMed

    Marín, Alicia; Martín, Margarita; Liñán, Olga; Alvarenga, Felipe; López, Mario; Fernández, Laura; Büchser, David; Cerezo, Laura

    2015-01-01

    Radiation-induced bystander effects are defined as biological effects expressed after irradiation by cells whose nuclei have not been directly irradiated. These effects include DNA damage, chromosomal instability, mutation, and apoptosis. There is considerable evidence that ionizing radiation affects cells located near the site of irradiation, which respond individually and collectively as part of a large interconnected web. These bystander signals can alter the dynamic equilibrium between proliferation, apoptosis, quiescence or differentiation. The aim of this review is to examine the most important biological effects of this phenomenon with regard to areas of major interest in radiotherapy. Such aspects include radiation-induced bystander effects during the cell cycle under hypoxic conditions when administering fractionated modalities or combined radio-chemotherapy. Other relevant aspects include individual variation and genetics in toxicity of bystander factors and normal tissue collateral damage. In advanced radiotherapy techniques, such as intensity-modulated radiation therapy (IMRT), the high degree of dose conformity to the target volume reduces the dose and, therefore, the risk of complications, to normal tissues. However, significant doses can accumulate out-of-field due to photon scattering and this may impact cellular response in these regions. Protons may offer a solution to reduce out-of-field doses. The bystander effect has numerous associated phenomena, including adaptive response, genomic instability, and abscopal effects. Also, the bystander effect can influence radiation protection and oxidative stress. It is essential that we understand the mechanisms underlying the bystander effect in order to more accurately assess radiation risk and to evaluate protocols for cancer radiotherapy.

  6. Radiotherapy in the UK

    SciTech Connect

    Ramsay, S.

    1993-10-09

    What is wrong with radiation treatment in the UK Is it bad practice or merely bad publicity Between 1982 and 1991, 1,000 patients receiving isocentric radiation therapy at the North Staffordshire Royal Infirmary received a substantial underdose of radiation; the clinical report on this incident was published last week. The operator had been using a correction factor for tumor-to-skin distance, unaware that this factor had already been applied by the computer system. Although the report pointed out that it is not surprising that the clinicians were not alerted to the undertreatment, is also noted that there were no resources at the hospital to audit the outcome of radiotherapy.

  7. [Radiotherapy during pregnancy].

    PubMed

    Mazeron, R; Barillot, I; Mornex, F; Giraud, P

    2016-09-01

    The diagnostic of cancer during pregnancy is a rare and delicate situation. As the developments of the embryo and the human fetus are extremely sensitive to ionizing radiations, the treatment of these tumors should be discussed. The studies - preclinical and clinical - based mostly on exposure accidents show that subdiaphragmatic treatments are possible during pregnancy. When radiotherapy is used, phantom estimations of the dose to the fetus, confirmed by in vivo measurements are required. Irradiation and imaging techniques should be arranged to decrease as much as possible the dose delivered to the fetus and hold below the threshold of 0.1Gy.

  8. Imaging in radiotherapy

    NASA Astrophysics Data System (ADS)

    Calandrino, R.; Del Maschio, A.; Cattaneo, G. M.; Castiglioni, I.

    2009-09-01

    The diagnostic methodologies used for the radiotherapy planning have undergone great developments in the last 30 years. Since the 1980s, after the introduction of the CT scanner, the modality for the planning moved beyond the planar 2D assessment to approach a real and more realistic volumetric 3D definition. Consequently the dose distribution, previously obtained by means of an overly simple approximation, became increasingly complex, better tailoring the true shape of the tumour. The final therapeutic improvement has been obtained by a parallel increase in the complexity of the irradiating units: the Linacs for therapy have, in fact, been equipped with a full accessory set capable to modulate the fluence (IMRT) and to check the correct target position continuously during the therapy session (IMRT-IGRT). The multimodal diagnostic approach, which integrates diagnostic information, from images of the patient taken with CT, NMR, PET and US, further improves the data for a biological and topological optimization of the radiotherapy plan and consequently of the dose distribution in the Planning Target Volume. Proteomic and genomic analysis will be the next step in tumour diagnosis. These methods will provide the planners with further information, for a true personalization of the treatment regimen and the assessment of the predictive essays for each tumour and each patient.

  9. Fertility impairment in radiotherapy

    PubMed Central

    Kuźba-Kryszak, Tamara; Nowikiewicz, Tomasz; Żyromska, Agnieszka

    2016-01-01

    Infertility as a result of antineoplastic therapy is becoming a very important issue due to the growing incidence of neoplastic diseases. Routinely applied antineoplastic treatments and the illness itself lead to fertility disorders. Therapeutic methods used in antineoplastic treatment may cause fertility impairment or sterilization due to permanent damage to reproductive cells. The risk of sterilization depends on the patient's sex, age during therapy, type of neoplasm, radiation dose and treatment area. It is known that chemotherapy and radiotherapy can lead to fertility impairment and the combination of these two gives an additive effect. The aim of this article is to raise the issue of infertility in these patients. It is of growing importance due to the increase in the number of children and young adults who underwent radiotherapy in the past. The progress in antineoplastic therapy improves treatment results, but at the same time requires a deeper look at existential needs of the patient. Reproductive function is an integral element of self-esteem and should be taken into account during therapy planning. PMID:27647982

  10. [Hodgkin's lymphoma and radiotherapy].

    PubMed

    Datsenko, P V; Panshin, G A

    2015-01-01

    After a median observation time of 4,5 years, 440 patients with Hodgkin's lymphoma stage I-IV to the Ann Arbor classification were treated with radiotherapy (2200 lymph areas) and ABVD (n=204) or BEACOPP (n=117) or CEA/ABVD (lomustine, etoposide, adriamycine, bleomycine, vinblastine and dacarbacine; n=119) regimens in 1995-2012. Correct allocation of groups with "CR or PR ≥80%" and "PR: 0-79%", after first-line chemotherapy, is extremely important for following RT planning. Adaptation of patients with Hodgkin's lymphoma can take place only after successful treatment, the probability of relapse and fear of repeated courses strongly interfere with this process, especially in the first years after its closure. Duration of remission period, especially in young people, is no less important than the criteria for overall survival. It is impossible to build recommendations for treatment for Hodgkin's lymphoma, based only on long-term survival rates. Importance of radiotherapy in reducing the number of relapses is undeniable, so the idea that the development of the role of chemotherapy in the treatment of the ray method Hodgkin's lymphoma gradually becomes secondary is in serious doubt. Our findings suggest the importance of both maintaining a high disease-free survival and reducing long-term complications in designing treatments of Hodgkin's lymphoma.

  11. [Stereotactic radiosurgery and radiotherapy for brain metastases].

    PubMed

    Tanguy, Ronan; Métellus, Philippe; Mornex, Françoise; Mazeron, Jean-Jacques

    2013-01-01

    Brain metastases management is still controversial even though many trials are trying to define the respective roles of neurosurgery, whole-brain radiotherapy, single-dose stereotactic radiotherapy and fractionated stereotactic radiotherapy. In this article, we review data from trials that examine the role of radiosurgery and fractionated stereotactic radiotherapy in the management of brain metastases.

  12. A National project for in vivo dosimetry procedures in radiotherapy: First results

    NASA Astrophysics Data System (ADS)

    Piermattei, Angelo; Greco, Francesca; Azario, Luigi; Porcelli, Andrea; Cilla, Savino; Zucca, Sergio; Russo, Aniello; di Castro, Elisabetta; Russo, Mariateresa; Caivano, Rocchina; Fusco, Vincenzo; Morganti, Alessio; Fidanzio, Andrea

    2012-03-01

    The paper reports the results of a National project financed by the Istituto Nazionale di Fisica Nucleare (INFN) for the development of in vivo dosimetric procedures in radiotherapy. In particular, a generalized procedure for the in vivo reconstruction of the isocenter dose, Diso, has been developed for 3D conformal radiotherapy treatments with open and wedged X-ray beams supplied by linacs of different manufacturers and equipped with aSi Electronic Portal Imaging Devices (EPIDs). In this way, the commissioning procedure is very simplified and applicable to Elekta, Siemens and Varian linacs. The method here reported is based on measurements in solid-water phantoms of different thicknesses, w, irradiated by square field sizes, L. Generalized mid-plane doses, D0, and transit signal by EPIDs, st0, obtained by 19 open and 38 wedged beams of 8 different linacs, were determined taking into account X-ray beam and EPID calibrations. Generalized ratios F0 = st0/D0 for open and wedged beams were fitted by surface equations and used by a dedicated software, for the Diso reconstruction. Moreover, for each beam the software supplied a set of transit signal profiles crossing the beam central axis to test the beam irradiation reproducibility. The tolerance level of the comparison between the Diso and the dose computed by the TPS, Diso,TPS, was estimated 5%. The generalized in vivo dosimetry procedure was adopted by 3 centers that used different linacs. The results of 480 tests showed that in absence of errors, the comparison between Diso and Diso,TPS resulted well-within the tolerance level. The presence of errors was detected in 10% of the tests and were due to essentially an incorrect set-up, presence of an attenuator on the beams and patient morphological changes. Moreover, the dedicated software used the information of the Record and Verify system of the centres and consequently the extra-time needed to obtain, for each beam, the Diso reconstruction after the dose delivery

  13. Radiotherapy in Phyllodes Tumour

    PubMed Central

    Sasidharan, Balukrishna; Manipadam, Marie Therese; Paul, M J; Backianathan, Selvamani

    2017-01-01

    Introduction Phyllodes Tumour (PT) of the breast is a relatively rare breast neoplasm (<1%) with diverse range of pathology and biological behaviour. Aim To describe the clinical course of PT and to define the role of Radiotherapy (RT) in PT of the breast. Materials and Methods Retrospective analysis of hospital data of patients with PT presented from 2005 to 2014 was done. Descriptive statistics was used to analyze the results. Simple description of data was done in this study. Age and duration of symptoms were expressed in median and range. Percentages, tables and general discussions were used to understand the meaning of the data analyzed. Results Out of the 98 patients, 92 were eligible for analysis. The median age of presentation was 43 years. A total of 64/92 patients were premenopausal. There was no side predilection for this tumour but 57/92 patients presented as an upper outer quadrant lump. Fifty percent of the patients presented as giant (10 cm) PT. The median duration of symptoms was 12 months (range: 1-168 months). A 60% of patients had Benign (B), 23% had Borderline (BL) and 17% had malignant (M) tumours. The surgical treatment for benign histology included Lumpectomy (L) for 15%, Wide Local Excision (WLE) for 48%, and Simple Mastectomy (SM) for 37%. All BL and M tumours were treated with WLE or SM. There was no recurrence in B and BL group when the margin was ≥1 cm. All non-metastatic M tumours received adjuvant RT irrespective of their margin status. Total 3/16 patients with M developed local recurrence. Total 6/16 M patients had distant metastases (lung or bone). Our median duration of follow up was 20 months (range: 1-120 months). Conclusion Surgical resection with adequate margins (>1 cm) gave excellent local control in B and BL tumours. For patients with BL PT, local radiotherapy is useful, if margins are close or positive even after the best surgical resection. There is a trend towards improved local control with adjuvant radiotherapy for

  14. [Respiratory synchronization and breast radiotherapy].

    PubMed

    Mège, A; Ziouèche-Mottet, A; Bodez, V; Garcia, R; Arnaud, A; de Rauglaudre, G; Pourel, N; Chauvet, B

    2016-10-01

    Adjuvant radiation therapy following breast cancer surgery continues to improve locoregional control and overall survival. But the success of highly targeted-conformal radiotherapy such as intensity-modulated techniques, can be compromised by respiratory motion. The intrafraction motion can potentially result in significant under- or overdose, and also expose organs at risk. This article summarizes the respiratory motion and its effects on imaging, dose calculation and dose delivery by radiotherapy for breast cancer. We will review the methods of respiratory synchronization available for breast radiotherapy to minimize the respiratory impact and to spare organs such as heart and lung.

  15. [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.

  16. Radiotherapy Planning using MRI

    PubMed Central

    Schmidt, Maria A; Payne, Geoffrey S

    2016-01-01

    The use of Magnetic Resonance Imaging (MRI) in Radiotherapy (RT) planning is rapidly expanding. We review the wide range of image contrast mechanisms available to MRI and the way they are exploited for RT planning. However a number of challenges are also considered: the requirements that MR images are acquired in the RT treatment position, that they are geometrically accurate, that effects of patient motion during the scan are minimised, that tissue markers are clearly demonstrated, that an estimate of electron density can be obtained. These issues are discussed in detail, prior to the consideration of a number of specific clinical applications. This is followed by a brief discussion on the development of real-time MRI-guided RT. PMID:26509844

  17. Radiotherapy on hidradenocarcinoma

    PubMed Central

    Lalya, Issam; Hadadi, Khalid; Tazi, El Mehdi; Lalya, Ilham; Bazine, Amine; Andaloussy, Khalid; Elmarjany, Mohamed; Sifat, Hassan; Hassouni, Khalid; Kebdani, Tayeb; Mansouri, Hamid; Benjaafar, Noureddine; Elgueddari, Brahim Khalil

    2011-01-01

    Context: Clear cell Hidradenocarcinoma is a rare carcinoma arising from sweat glands. It is an aggressive tumor that most metastasizes to regional lymph nodes and distant viscera; surgery with safe margins is the mainstay of treatment. Case Report: We report a case of 68-year-old woman who presented with an invasive clear cell hidradenocarcinoma situated in the left parotid area which recurred 5 months after surgery, this recurrence was managed successfully by high-dose irradiation of the tumor bed (66 Gy) and regional lymphatic chains (50 Gy), after a follow-up of more than 15 months, the patient is in good local control without significant toxicity. Conclusion: Post operative radiotherapy allows better local control and should be mandatory when histological features predictive of recurrence are present: positive margins, histology poorly differentiated, perineural invasion, vascular and lymphatic invasion, lymph node involvement, and extracapsular spread. PMID:22540063

  18. [Hepatic tumors and radiotherapy].

    PubMed

    Rio, E; Mornex, F; Peiffert, D; Huertas, A

    2016-09-01

    Recent technological developments led to develop the concept of focused liver radiation therapy. We must distinguish primary and secondary tumors as the indications are restricted and must be discussed as an alternative to surgical or medical treatments. For hepatocellular carcinoma 5 to 10cm (or more), a conformational radiation with or without intensity modulation is performed. Stereotactic body radiotherapy (SBRT) is being evaluated and is increasingly proposed as an alternative to radiofrequency ablative treatment for primary or secondary tumors (typically less than 5cm). Tumor (and liver) movements induced by respiratory motions must be taken into account. Strict dosimetric criteria must be met with particular attention to the dose-volume histograms to liver and the hollow organs, including cases of SBRT.

  19. [Radiotherapy for nasopharyngeal carcinoma].

    PubMed

    Maingon, P; Blanchard, P; Bidault, F; Calmels, L

    2016-09-01

    Nasapharyngeal carcinoma is a rare disease. Oftenly, the diagnostic is made for advanced disease. Localized tumors, T1 or T2 NO observed a good prognosis and are locally controlled in more than 90 % of the cases by radiotherapy alone. The standard treatment of locally advanced disease is combined chemoradiation. A special vigilance of fast decrease of the volume of the pathological lymph nodes, sometimes associated to loss of weight might indicate an adaptive dosimetric revision. The treatment of recurrent disease is of great importance. Surgical indications are limited but should be discussed in multidisciplinary tumor board when possible. Surgical nodal sampling has to be proposed for nodal recurrence as well as reirradiation, which could be indicated according to the technical issues.

  20. Pion radiotherapy at LAMPF

    SciTech Connect

    Bush, S.E.; Smith, A.R.; Zink, S.

    1982-12-01

    Clinical investigations of pi meson radiotherapy were conducted by the Cancer Research and Treatment Center of the University of New Mexico and the Los Alamos National Laboratory from 1974 until 1982. Two hundred and thirty patients have been treated for a variety of locally advanced primary and metastatic neoplasms. One hundred and ninety-six patients have been followed for a minimum of 18 months. Crude survival data range from 11% for unresectable pancreatic carcinoma to 82% for Stages C and D1 adenocarcinoma of the prostate. Acute tolerance of normal tissues is approximately 4500 pion rad in 36 fractions over 7 weeks. Severe chronic reactions have appeared with increasing frequency after doses in excess of 4000 pion rad.

  1. Bone Health and Pelvic Radiotherapy.

    PubMed

    Higham, C E; Faithfull, S

    2015-11-01

    Survivors who have received pelvic radiotherapy make up many of the long-term cancer population, with therapies for gynaecological, bowel, bladder and prostate malignancies. Individuals who receive radiotherapy to the pelvis as part of their cancer treatment are at risk of insufficiency fractures. Symptoms of insufficiency fractures include pelvic and back pain and immobility, which can affect substantially quality of life. This constellation of symptoms can occur within 2 months of radiotherapy up to 63 months post-treatment, with a median incidence of 6-20 months. As a condition it is under reported and evidence is poor as to the contributing risk factors, causation and best management to improve the patient's bone health and mobility. As radiotherapy advances, chronic symptoms, such as insufficiency fractures, as a consequence of treatment need to be better understood and reviewed. This overview explores the current evidence for the effect of radiotherapy on bone health and insufficiency fractures and identifies what we know and where gaps in our knowledge lie. The overview concludes with the need to take seriously complaints of pelvic pain from patients after pelvic radiotherapy and to investigate and manage these symptoms more effectively. There is a clear need for definitive research in this field to provide the evidence-based guidance much needed in practice.

  2. Potential of Adaptive Radiotherapy to Escalate the Radiation Dose in Combined Radiochemotherapy for Locally Advanced Non-Small Cell Lung Cancer

    SciTech Connect

    Guckenberger, Matthias; Wilbert, Juergen; Richter, Anne; Baier, Kurt; Flentje, Michael

    2011-03-01

    Purpose: To evaluate the potential of adaptive radiotherapy (ART) for advanced-stage non-small cell lung cancer (NSCLC) in terms of lung sparing and dose escalation. Methods and Materials: In 13 patients with locally advanced NSCLC, weekly CT images were acquired during radio- (n = 1) or radiochemotherapy (n = 12) for simulation of ART. Three-dimensional (3D) conformal treatment plans were generated: conventionally fractionated doses of 66 Gy were prescribed to the planning target volume without elective lymph node irradiation (Plan{sub 3}D). Using a surface-based algorithm of deformable image registration, accumulated doses were calculated in the CT images acquired during the treatment course (Plan{sub 4}D). Field sizes were adapted to tumor shrinkage once in week 3 or 5 and twice in weeks 3 and 5. Results: A continuous tumor regression of 1.2% per day resulted in a residual gross tumor volume (GTV) of 49% {+-} 15% after six weeks of treatment. No systematic differences between Plan{sub 3}D and Plan{sub 4}D were observed regarding doses to the GTV, lung, and spinal cord. Plan adaptation to tumor shrinkage resulted in significantly decreased lung doses without compromising GTV coverage: single-plan adaptation in Week 3 or 5 and twice-plan adaptation in Weeks 3 and 5 reduced the mean lung dose by 5.0% {+-} 4.4%, 5.6% {+-} 2.9% and 7.9% {+-} 4.8%, respectively. This lung sparing with twice ART allowed an iso-mean lung dose escalation of the GTV dose from 66.8 Gy {+-} 0.8 Gy to 73.6 Gy {+-} 3.8 Gy. Conclusions: Adaptation of radiotherapy to continuous tumor shrinkage during the treatment course reduced doses to the lung, allowed significant dose escalation and has the potential of increased local control.

  3. SU-E-T-348: Verification MU Calculation for Conformal Radiotherapy with Multileaf Collimator Using Report AAPM TG 114

    SciTech Connect

    Adrada, A; Tello, Z; Medina, L; Garrigo, E; Venencia, D

    2014-06-01

    Purpose: The purpose of this work was to develop and validate an open source independent MU dose calculation software for 3D conformal radiotherapy with multileaf high and low resolution according to the report of AAPM TG 11 Methods: Treatment plans were done using Iplan v4.5 BrainLAB TPS. A 6MV photon beam produced by Primus and Novalis linear accelerators equipped with an Optifocus MLC and HDMLC, respectively. TPS dose calculation algorithms were pencil beam and Monte Carlo. 1082 treatments plans were selected for the study. The algorithm was written in free and open source CodeBlocks C++ platform. Treatment plans were imported by the software using RTP format. Equivalent size field is obtained from the positions of the leaves; the effective depth of calculation can be introduced by TPS's dosimetry report or automatically calculated starting from SSD. The inverse square law is calculated by the 3D coordinates of the isocenter and normalization point of the treatment plan. The dosimetric parameters TPR, Sc, Sp and WF are linearly interpolated. Results: 1082 plans of both machines were analyzed. The average uncertainty between the TPS and the independent calculation was −0.43% ± 2.42% [−7.90%, 7.50%]. Specifically for the Primus the variation obtained was −0.85% ± 2.53% and for the Novalis 0.00% ± 2.23%. Data show that 94.8% of the cases the uncertainty was less than or equal to 5%, while 98.9% is less than or equal to 6%. Conclusion: The developed software is appropriate for use in calculation of UM. This software can be obtained upon request.

  4. Investigation of conformal and intensity-modulated radiation therapy techniques to determine the absorbed fetal dose in pregnant patients with breast cancer

    SciTech Connect

    Öğretici, Akın Akbaş, Uğur; Köksal, Canan; Bilge, Hatice

    2016-07-01

    The aim of this research was to investigate the fetal doses of pregnant patients undergoing conformal radiotherapy or intensity-modulated radiation therapy (IMRT) for breast cancers. An Alderson Rando phantom was chosen to simulate a pregnant patient with breast cancer who is receiving radiation therapy. This phantom was irradiated using the Varian Clinac DBX 600 system (Varian Medical System, Palo Alto, CA) linear accelerator, according to the standard treatment plans of both three-dimensional conformal radiation therapy (3-D CRT) and IMRT techniques. Thermoluminescent dosimeters were used to measure the irradiated phantom's virtually designated uterus area. Thermoluminescent dosimeter measurements (in the phantom) revealed that the mean cumulative fetal dose for 3-D CRT is 1.39 cGy and for IMRT it is 8.48 cGy, for a pregnant breast cancer woman who received radiation treatment of 50 Gy. The fetal dose was confirmed to increase by 70% for 3-D CRT and 40% for IMRT, if it is closer to the irradiated field by 5 cm. The mean fetal dose from 3-D CRT is 1.39 cGy and IMRT is 8.48 cGy, consistent with theoretic calculations. The IMRT technique causes the fetal dose to be 5 times more than that of 3-D CRT. Theoretic knowledge concerning the increase in the peripheral doses as the measurements approached the beam was also practically proven.

  5. [Adaptative radiotherapy: The case for MRI-guided radiotherapy].

    PubMed

    Maingon, P

    2016-10-01

    The concept of image-guided radiotherapy benefits from the development of magnetic resonance imaging (MRI) associated with different capacities of tissue analyses such as spectroscopy or diffusion analysis. The production of devices allowing the repositioning of patients through MRI represents a strong added value without delivering any additional dose to the patient while the optimization of the adaptative strategies are facilitated by a better contrast of the soft tissues compared to the scanner. The advantages of MRI are well demonstrated for brain tumours, head and neck carcinomas, pelvic tumors, mediastinal malignancies, gastrointestinal tract diseases. Adaptative radiotherapy inaugurates a new area of radiotherapy with different modalities. Several technological solutions are provided or discussed allowing the patients to benefit from thses new technologies as soon as possible.

  6. [Postoperative radiotherapy of prostate cancer].

    PubMed

    Guérif, S; Latorzeff, I; Lagrange, J-L; Hennequin, C; Supiot, S; Garcia, A; François, P; Soulié, M; Richaud, P; Salomon, L

    2014-10-01

    Between 10 and 40% of patients who have undergone a radical prostatectomy may have a biologic recurrence. Local or distant failure represents the possible patterns of relapse. Patients at high-risk for local relapse have extraprostatic disease, positive surgical margins or seminal vesicles infiltration or high Gleason score at pathology. Three phase-III randomized clinical trials have shown that, for these patients, adjuvant irradiation reduces the risk of tumoral progression without higher toxicity. Salvage radiotherapy for late relapse allows a disease control in 60-70% of the cases. Several research in order to improve the therapeutic ratio of the radiotherapy after prostatectomy are evaluate in the French Groupe d'Étude des Tumeurs Urogénitales (Gétug) and of the French association of urology (Afu). The Gétug-Afu 17 trial will provide answers to the question of the optimal moment for postoperative radiotherapy for pT3-4 R1 pN0 Nx patients, with the objective of comparing an immediate treatment to a differed early treatment initiated at biological recurrence. The Gétug-Afu 22 questions the place of a short hormonetherapy combined with image-guided, intensity-modulated radiotherapy (IMRT) in adjuvant situation for a detectable prostate specific antigen (PSA). The implementation of a multicenter quality control within the Gétug-Afu in order to harmonize a modern postoperative radiotherapy will allow the development of a dose escalation IMRT after surgery.

  7. Optimization of 3D conformal electron beam therapy in inhomogeneous media by concomitant fluence and energy modulation

    NASA Astrophysics Data System (ADS)

    Åsell, Mats; Hyödynmaa, Simo; Gustafsson, Anders; Brahme, Anders

    1997-11-01

    The possibilities of using simultaneous fluence and energy modulation techniques in electron beam therapy to shape the dose distribution and almost eliminate the influences of tissue inhomogeneities have been investigated. By using a radiobiologically based optimization algorithm the radiobiological properties of the tissues can be taken into account when trying to find the best possible dose delivery. First water phantoms with differently shaped surfaces were used to study the effect of surface irregularities. We also studied water phantoms with internal inhomogeneities consisting of air or cortical bone. It was possible to improve substantially the dose distribution by fluence modulation in these cases. In addition to the fluence modulation the most suitable single electron energy in each case was also determined. Finally, the simultaneous use of several preselected electron beam energies was also tested, each with an individually optimized fluence profile. One to six electron energies were used, resulting in a slow improvement in complication-free cure with increasing number of beam energies. To apply these techniques to a more clinically relevant situation a post-operative breast cancer patient was studied. For simplicity this patient was treated with only one anterior beam portal to clearly illustrate the effect of inhomogeneities like bone and lung on the dose distribution. It is shown that by using fluence modulation the influence of dose inhomogeneities can be significantly reduced. When two or more electron beam energies with individually optimized fluence profiles are used the dose conformality to the internal target volume is further increased, particularly for targets with complex shapes.

  8. Treatment techniques for 3D conformal radiation to breast and chest wall including the internal mammary chain.

    PubMed

    Sonnik, Deborah; Selvaraj, Raj N; Faul, Clare; Gerszten, Kristina; Heron, Dwight E; King, Gwendolyn C

    2007-01-01

    Breast, chest wall, and regional nodal irradiation have been associated with an improved outcome in high-risk breast cancer patients. Complex treatment planning is often utilized to ensure complete coverage of the target volume while minimizing the dose to surrounding normal tissues. The 2 techniques evaluated in this report are the partially wide tangent fields (PWTFs) and the 4-field photon/electron combination (the modified "Kuske Technique"). These 2 techniques were evaluated in 10 consecutive breast cancer patients. All patients had computerized tomographic (CT) scans for 3D planning supine on a breast board. The breast was defined clinically by the physician and confirmed radiographically with radiopaque bebes. The resulting dose-volume histograms (DVHs) of normal and target tissues were then compared. The deep tangent field with blocks resulted in optimal coverage of the target and the upper internal mammary chain (IMC) while sparing of critical and nontarget tissues. The wide tangent technique required less treatment planning and delivery time. We compared the 2 techniques and their resultant DVHs and feasibility in a busy clinic.

  9. Treatment techniques for 3D conformal radiation to breast and chest wall including the internal mammary chain

    SciTech Connect

    Sonnik, Deborah; Selvaraj, Raj N. . E-mail: selvarajrn@upmc.edu; Faul, Clare; Gerszten, Kristina; Heron, Dwight E.; King, Gwendolyn C.

    2007-04-01

    Breast, chest wall, and regional nodal irradiation have been associated with an improved outcome in high-risk breast cancer patients. Complex treatment planning is often utilized to ensure complete coverage of the target volume while minimizing the dose to surrounding normal tissues. The 2 techniques evaluated in this report are the partially wide tangent fields (PWTFs) and the 4-field photon/electron combination (the modified 'Kuske Technique'). These 2 techniques were evaluated in 10 consecutive breast cancer patients. All patients had computerized tomographic (CT) scans for 3D planning supine on a breast board. The breast was defined clinically by the physician and confirmed radiographically with radiopaque bebes. The resulting dose-volume histograms (DVHs) of normal and target tissues were then compared. The deep tangent field with blocks resulted in optimal coverage of the target and the upper internal mammary chain (IMC) while sparing of critical and nontarget tissues. The wide tangent technique required less treatment planning and delivery time. We compared the 2 techniques and their resultant DVHs and feasibility in a busy clinic.

  10. Fractal Dimensions of Self-Avoiding Walks and Ising High-Temperature Graphs in 3D Conformal Bootstrap

    NASA Astrophysics Data System (ADS)

    Shimada, Hirohiko; Hikami, Shinobu

    2016-12-01

    The fractal dimensions of polymer chains and high-temperature graphs in the Ising model both in three dimension are determined using the conformal bootstrap applied for the continuation of the O( N) models from N=1 (Ising model) to N=0 (polymer). Even for non-integer N, the O( N) sum rule allows one to study the unitarity bound formally defined from the positivity, which may be violated in a non-unitary CFT. This unitarity bound of the scaling dimension for the O( N)-symmetric-tensor develops a kink as a function of the fundamental field as in the case of the energy operator dimension in the Z_2 (Ising) sum rule. Although this kink structure becomes less pronounced as N tends to zero, we found instead an emerging asymmetric minimum in the current central charge C_J. Despite the non-unitarity of the O( N) model at non-integer N, we find the C_J-kink along the unitarity bound lies very close to the location of the infrared (IR) O( N) CFT estimated by other methods. It is pointed out that certain level degeneracies at the IR CFT should induce these singular shapes of the unitarity bounds. As an application to the quantum and classical spin systems, we also predict critical exponents associated with the N=1 supersymmetry, which could be relevant for locating the corresponding fixed point in the phase diagram.

  11. Five year outcomes of hypofractionated simultaneous integrated boost irradiation in breast conserving therapy; patterns of recurrence.

    PubMed

    Bantema-Joppe, Enja J; Vredeveld, Eline J; de Bock, Geertruida H; Busz, Dianne M; Woltman-van Iersel, Marleen; Dolsma, Wil V; van der Laan, Hans Paul; Langendijk, Johannes A; Maduro, John H

    2013-08-01

    In 2005, we introduced hypofractionated 3-dimensional conformal radiotherapy with a simultaneous integrated boost (3D-CRT-SIB) technique after breast conserving surgery. In a consecutive series of 752 consecutive female invasive breast cancer patients (stages I-III) the 5-year actuarial rate for local control was 98.9%. This new technique gives excellent 5-year local control.

  12. 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

  13. [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.

  14. Inflammatory Skin Conditions Associated With Radiotherapy.

    PubMed

    Hernández Aragüés, I; Pulido Pérez, A; Suárez Fernández, R

    2017-04-01

    Radiotherapy for cancer is used increasingly. Because skin cells undergo rapid turnover, the ionizing radiation of radiotherapy has collateral effects that are often expressed in inflammatory reactions. Some of these reactions-radiodermatitis and recall phenomenon, for example-are very familiar to dermatologists. Other, less common radiotherapy-associated skin conditions are often underdiagnosed but must also be recognized.

  15. Radiotherapy supports protective tumor-specific immunity

    PubMed Central

    Gupta, Anurag; Sharma, Anu; von Boehmer, Lotta; Surace, Laura; Knuth, Alexander; van den Broek, Maries

    2012-01-01

    Radiotherapy is an important therapeutic option for the treatment of cancer. Growing evidence indicates that, besides inducing an irreversible DNA damage, radiotherapy promotes tumor-specific immune response, which significantly contribute to therapeutic efficacy. We postulate that radiotherapy activates tumor-associated dendritic cells, thus changing the tolerogenic tumor environment into an immunogenic one. PMID:23264910

  16. Clinical quality standards for radiotherapy

    PubMed Central

    2012-01-01

    Aim of the study The technological progress that is currently being witnessed in the areas of diagnostic imaging, treatment planning systems and therapeutic equipment has caused radiotherapy to become a high-tech and interdisciplinary domain involving staff of various backgrounds. This allows steady improvement in therapy results, but at the same time makes the diagnostic, imaging and therapeutic processes more complex and complicated, requiring every stage of those processes to be planned, organized, controlled and improved so as to assure high quality of services provided. The aim of this paper is to present clinical quality standards for radiotherapy as developed by the author. Material and methods In order to develop the quality standards, a comparative analysis was performed between European and Polish legal acts adopted in the period of 1980-2006 and the universal industrial ISO 9001:2008 standard, defining requirements for quality management systems, and relevant articles published in 1984-2009 were reviewed, including applicable guidelines and recommendations of American, international, European and Polish bodies, such as the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy & Oncology (ESTRO), the International Atomic Energy Agency (IAEA), and the Organisation of European Cancer Institutes (OECI) on quality assurance and management in radiotherapy. Results As a result, 352 quality standards for radiotherapy were developed and categorized into the following three groups: 1 – organizational standards; 2 – physico-technical standards and 3 – clinical standards. Conclusion Proposed clinical quality standards for radiotherapy can be used by any institution using ionizing radiation for medical purposes. However, standards are of value only if they are implemented, reviewed, audited and improved, and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:23788854

  17. Second Malignant Neoplasms Following Radiotherapy

    PubMed Central

    Kumar, Sanath

    2012-01-01

    More than half of all cancer patients receive radiotherapy as a part of their treatment. With the increasing number of long-term cancer survivors, there is a growing concern about the risk of radiation induced second malignant neoplasm [SMN]. This risk appears to be highest for survivors of childhood cancers. The exact mechanism and dose-response relationship for radiation induced malignancy is not well understood, however, there have been growing efforts to develop strategies for the prevention and mitigation of radiation induced cancers. This review article focuses on the incidence, etiology, and risk factors for SMN in various organs after radiotherapy. PMID:23249860

  18. Combined Adjuvant Radiochemotherapy With IMRT/XELOX Improves Outcome With Low Renal Toxicity in Gastric Cancer

    SciTech Connect

    Boda-Heggemann, Judit; Hofheinz, Ralf-Dieter; Weiss, Christel; Mennemeyer, Philipp; Mai, Sabine K.; Hermes, Petra; Wertz, Hansjoerg; Post, Stefan; Massner, Bernd; Hieber, Udo; Hochhaus, Andreas; Wenz, Frederik; Lohr, Frank

    2009-11-15

    Objectives: Adjuvant radiochemotherapy improves survival of patients with advanced gastric cancer. We assessed in two sequential cohorts whether improved radiotherapy technique (IMRT) together with intensified chemotherapy improves outcome vs. conventional three-dimensional conformal radiotherapy (3D-CRT) and standard chemotherapy in these patients while maintaining or reducing renal toxicity. Materials and Methods: Sixty consecutive patients treated for gastric cancer either with 3D-CRT (n = 27) and IMRT (n = 33) were evaluated. More than 70% had undergone D2 resection. Although there was a slight imbalance in R0 status between cohorts, N+ status was balanced. Chemotherapy consisted predominantly of 5-fluorouracil/folinic acid (n = 36) in the earlier cohort and mostly of oxaliplatin/capecitabine (XELOX, n = 24) in the later cohort. Primary end points were overall survival (OS), disease-free survival (DFS), and renal toxicity based on creatinine levels. Results: Median follow-up (FU) of all patients in the 3D-CRT group was 18 months and in the IMRT group 22 months (median FU of surviving patients 67 months in the 3D-CRT group and 25 months in the IMRT group). Overall median survival (and DFS) were 18 (13) months in the 3D-CRT group and both not reached in the IMRT group (p = 0.0492 and 0.0216). Actuarial 2-year survival was 37% and 67% in the 3D-CRT and IMRT groups, respectively. No late renal toxicity >Grade 2 (LENT-SOMA scale) was observed in either cohort. Conclusion: When comparing sequentially treated patient cohorts with similar characteristics, OS and DFS improved with the use of IMRT and intensified chemotherapy without signs of increased renal toxicity.

  19. [Which rules apply to hypofractionated radiotherapy?].

    PubMed

    Supiot, S; Clément-Colmou, K; Paris, F; Corre, I; Chiavassa, S; Delpon, G

    2015-10-01

    Hypofractionated radiotherapy is now more widely prescribed due to improved targeting techniques (intensity modulated radiotherapy, image-guided radiotherapy and stereotactic radiotherapy). Low dose hypofractionated radiotherapy is routinely administered mostly for palliative purposes. High or very high dose hypofractionated irradiation must be delivered according to very strict procedures since every minor deviation can lead to major changes in dose delivery to the tumor volume and organs at risk. Thus, each stage of the processing must be carefully monitored starting from the limitations and the choice of the hypofractionation technique, tumour contouring and dose constraints prescription, planning and finally dose calculation and patient positioning verification.

  20. Postoperative Radiotherapy in Prostate Cancer: The Case of the Missing Target

    SciTech Connect

    Croke, Jennifer; Malone, Shawn; Roustan Delatour, Nicolas; Belanger, Eric; Avruch, Leonard; Morash, Christopher; Kayser, Cathleen; Underhill, Kathryn; Spaans, Johanna

    2012-07-15

    Purpose: Postoperative radiotherapy (XRT) increases survival in high-risk prostate cancer patients. Approximately 50% of patients on long-term follow-up relapse despite adjuvant XRT and the predominant site of failure remains local. Four consensus guidelines define postoperative clinical target volume (CTV) in prostate cancer. We explore the possibility that inadequate CTV coverage is an important cause of local failure. This study evaluates the utility of preoperative magnetic resonance imaging (MRI) in defining prostate bed CTV. Methods and Materials: Twenty prostate cancer patients treated with postoperative XRT who also had preoperative staging MRI were included. The four guidelines were applied and the CTVs were expanded to create planning target volumes (PTVs). Preoperative MRIs were fused with postoperative planning CT scans. MRI-based prostate and gross visible tumors were contoured. Three-dimensional (3D) conformal four- and six-field XRT plans were developed and dose-volume histograms analyzed. Subtraction analysis was conducted to assess the adequacy of prostate/gross tumor coverage. Results: Gross tumor was visible in 18 cases. In all 20 cases, the consensus CTVs did not fully cover the MRI-defined prostate. On average, 35% of the prostate volume and 32% of the gross tumor volume were missed using six-field 3D treatment plans. The entire MRI-defined gross tumor volume was completely covered in only two cases (six-field plans). The expanded PTVs did not cover the entire prostate bed in 50% of cases. Prostate base and mid-zones were the predominant site of inadequate coverage. Conclusions: Current postoperative CTV guidelines do not adequately cover the prostate bed and/or gross tumor based on preoperative MRI imaging. Additionally, expanded PTVs do not fully cover the prostate bed in 50% of cases. Inadequate CTV definition is likely a major contributing factor for the high risk of relapse despite adjuvant XRT. Preoperative imaging may lead to more

  1. Radiotherapy T1 glottic carcinoma

    SciTech Connect

    Zablow, A.I.; Erba, P.S.; Sanfillippo, L.J.

    1989-11-01

    From 1970 to 1985, curative radiotherapy was administered to 63 patients with stage I carcinoma of the true vocal cords. Precision radiotherapeutic technique yields cure rates comparable to surgical results. Good voice quality was preserved in a high percentage of patients.

  2. Reducing the Risk of Xerostomia and Mandibular Osteoradionecrosis: The Potential Benefits of Intensity Modulated Radiotherapy in Advanced Oral Cavity Carcinoma

    SciTech Connect

    Ahmed, Merina; Hansen, Vibeke N.; Harrington, Kevin J.; Nutting, Christopher M.

    2009-10-01

    Radiation therapy for squamous cell carcinoma of the oral cavity may be curative, but carries a risk of permanent damage to bone, salivary glands, and other soft tissues. We studied the potential of intensity modulated radiotherapy (IMRT) to improve target volume coverage, and normal tissue sparing for advanced oral cavity carcinoma (OCC). Six patients with advanced OCC requiring bilateral irradiation to the oral cavity and neck were studied. Standard 3D conformal radiotherapy (3DCRT) and inverse-planned IMRT dose distributions were compared by using dose-volume histograms. Doses to organs at risk, including spinal cord, parotid glands, and mandible, were assessed as surrogates of radiation toxicity. PTV1 mean dose was 60.8 {+-} 0.8 Gy for 3DCRT and 59.8 {+-} 0.1 Gy for IMRT (p = 0.04). PTV1 dose range was 24.7 {+-} 6 Gy for 3DCRT and 15.3 {+-} 4 Gy for IMRT (p = 0.001). PTV2 mean dose was 54.5 {+-} 0.8 Gy for 3DCRT and for IMRT was 54.2 {+-} 0.2 Gy (p = 0.34). PTV2 dose range was improved by IMRT (7.8 {+-} 3.2 Gy vs. 30.7 {+-} 12.8 Gy, p = 0.006). Homogeneity index (HI) values for PTV2 were closer to unity using IMRT (p = 0.0003). Mean parotid doses were 25.6 {+-} 2.7 Gy for IMRT and 42.0 {+-} 8.8 Gy with 3DCRT (p = 0.002). The parotid V30 in all IMRT plans was <45%. The mandible V50, V55, and V60 were significantly lower for the IMRT plans. Maximum spinal cord and brain stem doses were similar for the 2 techniques. IMRT provided superior target volume dose homogeneity and sparing of organs at risk. The magnitude of reductions in dose to the salivary glands and mandible are likely to translate into reduced incidence of xerostomia and osteoradionecrosis for patients with OCC.

  3. Reducing the risk of xerostomia and mandibular osteoradionecrosis: the potential benefits of intensity modulated radiotherapy in advanced oral cavity carcinoma.

    PubMed

    Ahmed, Merina; Hansen, Vibeke N; Harrington, Kevin J; Nutting, Christopher M

    2009-01-01

    Radiation therapy for squamous cell carcinoma of the oral cavity may be curative, but carries a risk of permanent damage to bone, salivary glands, and other soft tissues. We studied the potential of intensity modulated radiotherapy (IMRT) to improve target volume coverage, and normal tissue sparing for advanced oral cavity carcinoma (OCC). Six patients with advanced OCC requiring bilateral irradiation to the oral cavity and neck were studied. Standard 3D conformal radiotherapy (3DCRT) and inverse-planned IMRT dose distributions were compared by using dose-volume histograms. Doses to organs at risk, including spinal cord, parotid glands, and mandible, were assessed as surrogates of radiation toxicity. PTV1 mean dose was 60.8 +/- 0.8 Gy for 3DCRT and 59.8 +/- 0.1 Gy for IMRT (p = 0.04). PTV1 dose range was 24.7 +/- 6 Gy for 3DCRT and 15.3 +/- 4 Gy for IMRT (p = 0.001). PTV2 mean dose was 54.5 +/- 0.8 Gy for 3DCRT and for IMRT was 54.2 +/- 0.2 Gy (p = 0.34). PTV2 dose range was improved by IMRT (7.8 +/- 3.2 Gy vs. 30.7 +/- 12.8 Gy, p = 0.006). Homogeneity index (HI) values for PTV2 were closer to unity using IMRT (p = 0.0003). Mean parotid doses were 25.6 +/- 2.7 Gy for IMRT and 42.0 +/- 8.8 Gy with 3DCRT (p = 0.002). The parotid V30 in all IMRT plans was <45%. The mandible V50, V55, and V60 were significantly lower for the IMRT plans. Maximum spinal cord and brain stem doses were similar for the 2 techniques. IMRT provided superior target volume dose homogeneity and sparing of organs at risk. The magnitude of reductions in dose to the salivary glands and mandible are likely to translate into reduced incidence of xerostomia and osteoradionecrosis for patients with OCC.

  4. Development and evaluation of a clinical model for lung cancer patients using stereotactic body radiotherapy (SBRT) within a knowledge-based algorithm for treatment planning.

    PubMed

    Chin Snyder, Karen; Kim, Jinkoo; Reding, Anne; Fraser, Corey; Gordon, James; Ajlouni, Munther; Movsas, Benjamin; Chetty, Indrin J

    2016-11-01

    The purpose of this study was to describe the development of a clinical model for lung cancer patients treated with stereotactic body radiotherapy (SBRT) within a knowledge-based algorithm for treatment planning, and to evaluate the model performance and applicability to different planning techniques, tumor locations, and beam arrangements. 105 SBRT plans for lung cancer patients previously treated at our institution were included in the development of the knowledge-based model (KBM). The KBM was trained with a combination of IMRT, VMAT, and 3D CRT techniques. Model performance was validated with 25 cases, for both IMRT and VMAT. The full KBM encompassed lesions located centrally vs. peripherally (43:62), upper vs. lower (62:43), and anterior vs. posterior (60:45). Four separate sub-KBMs were created based on tumor location. Results were compared with the full KBM to evaluate its robustness. Beam templates were used in conjunction with the optimizer to evaluate the model's ability to handle suboptimal beam placements. Dose differences to organs-at-risk (OAR) were evaluated between the plans generated by each KBM. Knowledge-based plans (KBPs) were comparable to clinical plans with respect to target conformity and OAR doses. The KBPs resulted in a lower maximum spinal cord dose by 1.0±1.6Gy compared to clinical plans, p=0.007. Sub-KBMs split according to tumor location did not produce significantly better DVH estimates compared to the full KBM. For central lesions, compared to the full KBM, the peripheral sub-KBM resulted in lower dose to 0.035 cc and 5 cc of the esophagus, both by 0.4Gy±0.8Gy, p=0.025. For all lesions, compared to the full KBM, the posterior sub-KBM resulted in higher dose to 0.035 cc, 0.35 cc, and 1.2 cc of the spinal cord by 0.2±0.4Gy, p=0.01. Plans using template beam arrangements met target and OAR criteria, with an increase noted in maximum heart dose (1.2±2.2Gy, p=0.01) and GI (0.2±0.4, p=0.01) for the nine-field plans relative to KBPs

  5. [Stereotactic radiotherapy for pelvic tumors].

    PubMed

    Mazeron, R; Fumagalli, I

    2014-01-01

    Extracranial stereotactic radiotherapy is booming. The development and spread of dedicated accelerators coupled with efficient methods of repositioning can now allow treatments of mobile lesions with moderate size, with high doses per fraction. Intuitively, except for the prostate, pelvic tumours, often requiring irradiation of regional lymph node drainage, lend little to this type of treatment. However, in some difficult circumstances, such as boost or re-radiation, stereotactic irradiation condition is promising and clinical experiences have already been reported.

  6. Intraoperative radiotherapy for breast cancer

    PubMed Central

    Williams, Norman R.; Pigott, Katharine H.; Brew-Graves, Chris

    2014-01-01

    Intra-operative radiotherapy (IORT) as a treatment for breast cancer is a relatively new technique that is designed to be a replacement for whole breast external beam radiotherapy (EBRT) in selected women suitable for breast-conserving therapy. This article reviews twelve reasons for the use of the technique, with a particular emphasis on targeted intra-operative radiotherapy (TARGIT) which uses X-rays generated from a portable device within the operating theatre immediately after the breast tumour (and surrounding margin of healthy tissue) has been removed. The delivery of a single fraction of radiotherapy directly to the tumour bed at the time of surgery, with the capability of adding EBRT at a later date if required (risk-adaptive technique) is discussed in light of recent results from a large multinational randomised controlled trial comparing TARGIT with EBRT. The technique avoids irradiation of normal tissues such as skin, heart, lungs, ribs and spine, and has been shown to improve cosmetic outcome when compared with EBRT. Beneficial aspects to both institutional and societal economics are discussed, together with evidence demonstrating excellent patient satisfaction and quality of life. There is a discussion of the published evidence regarding the use of IORT twice in the same breast (for new primary cancers) and in patients who would never be considered for EBRT because of their special circumstances (such as the frail, the elderly, or those with collagen vascular disease). Finally, there is a discussion of the role of the TARGIT Academy in developing and sustaining high standards in the use of the technique. PMID:25083504

  7. Dosimetric Advantages of Four-Dimensional Adaptive Image-Guided Radiotherapy for Lung Tumors Using Online Cone-Beam Computed Tomography

    SciTech Connect

    Harsolia, Asif; Hugo, Geoffrey D.; Kestin, Larry L. Grills, Inga S.; Yan Di

    2008-02-01

    Purpose: This study compares multiple planning techniques designed to improve accuracy while allowing reduced planning target volume (PTV) margins though image-guided radiotherapy (IGRT) with four-dimensional (4D) cone-beam computed tomography (CBCT). Methods and Materials: Free-breathing planning and 4D-CBCT scans were obtained in 8 patients with lung tumors. Four plans were generated for each patient: 3D-conformal, 4D-union, 4D-offline adaptive with a single correction (offline ART), and 4D-online adaptive with daily correction (online ART). For the 4D-union plan, the union of gross tumor volumes from all phases of the 4D-CBCT was created with a 5-mm expansion applied for setup uncertainty. For offline and online ART, the gross tumor volume was delineated at the mean position of tumor motion from the 4D-CBCT. The PTV margins were calculated from the random components of tumor motion and setup uncertainty. Results: Adaptive IGRT techniques provided better PTV coverage with less irradiated normal tissues. Compared with 3D plans, mean relative decreases in PTV volumes were 15%, 39%, and 44% using 4D-union, offline ART, and online ART planning techniques, respectively. This resulted in mean lung volume receiving {>=} 20Gy (V20) relative decreases of 21%, 23%, and 31% and mean lung dose relative decreases of 16%, 26%, and 31% for the 4D-union, 4D-offline ART, and 4D-online ART, respectively. Conclusions: Adaptive IGRT using CBCT is feasible for the treatment of patients with lung tumors and significantly decreases PTV volume and dose to normal tissues, allowing for the possibility of dose escalation. All analyzed 4D planning strategies resulted in improvements over 3D plans, with 4D-online ART appearing optimal.

  8. Bowel sparing in pediatric cranio-spinal radiotherapy: a comparison of combined electron and photon and helical TomoTherapy techniques to a standard photon method

    SciTech Connect

    Harron, Elizabeth; Lewis, Joanne

    2012-07-01

    The aim of this study was to compare the dose to organs at risk (OARs) from different craniospinal radiotherapy treatment approaches available at the Northern Centre for Cancer Care (NCCC), with a particular emphasis on sparing the bowel. Method: Treatment plans were produced for a pediatric medulloblastoma patient with inflammatory bowel disease using 3D conformal 6-MV photons (3DCP), combined 3D 6-MV photons and 18-MeV electrons (3DPE), and helical photon TomoTherapy (HT). The 3DPE plan was a modification of the standard 3DCP technique, using electrons to treat the spine inferior to the level of the diaphragm. The plans were compared in terms of the dose-volume data to OARs and the nontumor integral dose. Results: The 3DPE plan was found to give the lowest dose to the bowel and the lowest nontumor integral dose of the 3 techniques. However, the coverage of the spine planning target volume (PTV) was least homogeneous using this technique, with only 74.6% of the PTV covered by 95% of the prescribed dose. HT was able to achieve the best coverage of the PTVs (99.0% of the whole-brain PTV and 93.1% of the spine PTV received 95% of the prescribed dose), but delivered a significantly higher integral dose. HT was able to spare the heart, thyroid, and eyes better than the linac-based techniques, but other OARs received a higher dose. Conclusions: Use of electrons was the best method for reducing the dose to the bowel and the integral dose, at the expense of compromised spine PTV coverage. For some patients, HT may be a viable method of improving dose homogeneity and reducing selected OAR doses.

  9. Adjuvant and Definitive Radiotherapy for Adrenocortical Carcinoma

    SciTech Connect

    Sabolch, Aaron; Feng, Mary; Griffith, Kent; Hammer, Gary; Doherty, Gerard; Ben-Josef, Edgar

    2011-08-01

    Purpose: To evaluate the impact of both adjuvant and definitive radiotherapy on local control of adrenocortical carcinoma. Methods and Materials: Outcomes were analyzed from 58 patients with 64 instances of treatment for adrenocortical carcinoma at the University of Michigan's Multidisciplinary Adrenal Cancer Clinic. Thirty-seven of these instances were for primary disease, whereas the remaining 27 were for recurrent disease. Thirty-eight of the treatment regimens involved surgery alone, 10 surgery plus adjuvant radiotherapy, and 16 definitive radiotherapy for unresectable disease. The effects of patient, tumor, and treatment factors were modeled simultaneously using multiple variable Cox proportional hazards regression for associations with local recurrence, distant recurrence, and overall survival. Results: Local failure occurred in 16 of the 38 instances that involved surgery alone, in 2 of the 10 that consisted of surgery plus adjuvant radiotherapy, and in 1 instance of definitive radiotherapy. Lack of radiotherapy use was associated with 4.7 times the risk of local failure compared with treatment regimens that involved radiotherapy (95% confidence interval, 1.2-19.0; p = 0.030). Conclusions: Radiotherapy seems to significantly lower the risk of local recurrence/progression in patients with adrenocortical carcinoma. Adjuvant radiotherapy should be strongly considered after surgical resection.

  10. Escalated median dose for pituitary macroadenomas using intensity-modulated radiation therapy

    SciTech Connect

    Robinson, D.; Murray, B.; Underwood, L.; Halls, S.; Roa, W

    2004-03-31

    Three-dimensional conformal radiotherapy (3D CRT) has become an established treatment for pituitary macroadenomas. This study is an investigation into the possible dosimetric advantages of intensity-modulated radiotherapy for such critically located tumors. Three consecutive patients with pituitary macroadenoma previously treated with 3D CRT were replanned with inverse-planned IMRT using Helax-TMS (V.6.0, Helax AB, Uppsala, Sweden. Fusion of computed tomography (CT) with postoperative magnetic resonance imaging (MRI) was performed within the planning system to define the gross tumor volume (GTV), planning target volume (PTV), and normal structures including the optic chiasm. Dose-volume histograms (DVHs) for the 3D CRT plans were then compared with those of the corresponding prospective IMRT plans. Both techniques maintained critical structure doses below tolerance levels while maintaining a minimum dose of 45 Gy to 100% of the PTV. While IMRT plans deliver consistently more heterogeneous dose distributions to the PTV, the median PTV dose is elevated in the IMRT plans compared with the 3D CRT plans. For critically located tumors like these pituitary macroadenomas, IMRT allows escalation of the median dose to the tumor without an accompanying loss in critical structure sparing or creating unacceptable cold spots within the PTV.

  11. 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.

  12. Ion-induced nuclear radiotherapy

    DOEpatents

    Horn, Kevin M.; Doyle, Barney L.

    1996-01-01

    Ion-induced Nuclear Radiotherapy (INRT) is a technique for conducting radiosurgery and radiotherapy with a very high degree of control over the spatial extent of the irradiated volume and the delivered dose. Based upon the concept that low energy, ion induced atomic and nuclear reactions can be used to produce highly energetic reaction products at the site of a tumor, the INRT technique is implemented through the use of a conduit-needle or tube which conducts a low energy ion beam to a position above or within the intended treatment area. At the end of the conduit-needle or tube is a specially fabricated target which, only when struck by the ion beam, acts as a source of energetic radiation products. The inherent limitations in the energy, and therefore range, of the resulting reaction products limits the spatial extent of irradiation to a pre-defined volume about the point of reaction. Furthermore, since no damage is done to tissue outside this irradiated volume, the delivered dose may be made arbitrarily large. INRT may be used both as a point-source of radiation at the site of a small tumor, or as a topical bath of radiation to broad areas of diseased tissue.

  13. Ion-induced nuclear radiotherapy

    DOEpatents

    Horn, K.M.; Doyle, B.L.

    1996-08-20

    Ion-induced Nuclear Radiotherapy (INRT) is a technique for conducting radiosurgery and radiotherapy with a very high degree of control over the spatial extent of the irradiated volume and the delivered dose. Based upon the concept that low energy, ion induced atomic and nuclear reactions can be used to produce highly energetic reaction products at the site of a tumor, the INRT technique is implemented through the use of a conduit-needle or tube which conducts a low energy ion beam to a position above or within the intended treatment area. At the end of the conduit-needle or tube is a specially fabricated target which, only when struck by the ion beam, acts as a source of energetic radiation products. The inherent limitations in the energy, and therefore range, of the resulting reaction products limits the spatial extent of irradiation to a pre-defined volume about the point of reaction. Furthermore, since no damage is done to tissue outside this irradiated volume, the delivered dose may be made arbitrarily large. INRT may be used both as a point-source of radiation at the site of a small tumor, or as a topical bath of radiation to broad areas of diseased tissue. 25 figs.

  14. Consolidative Involved-Node Proton Therapy for Stage IA-IIIB Mediastinal Hodgkin Lymphoma: Preliminary Dosimetric Outcomes From a Phase II Study

    SciTech Connect

    Hoppe, Bradford S.; Flampouri, Stella; Su Zhong; Morris, Christopher G.; Latif, Naeem

    2012-05-01

    Purpose: To compare the dose reduction to organs at risk (OARs) with proton therapy (PT) versus three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) in patients with mediastinal Hodgkin lymphoma (HL) enrolled on a Phase II study of involved-node radiotherapy (INRT). Methods and Materials: Between June 2009 and October 2010, 10 patients were enrolled on a University of Florida institutional review board-approved protocol for de novo 'classical' Stage IA-IIIB HL with mediastinal (bulky or nonbulky) involvement after chemotherapy. INRT was planned per European Organization for Research and Treatment of Cancer guidelines. Three separate optimized plans were developed for each patient: 3D-CRT, IMRT, and PT. The primary end point was a 50% reduction in the body V4 with PT compared with 3D-CRT or IMRT. Results: The median relative reduction with PT in the primary end point, body V4, was 51% compared with 3D-CRT (p = 0.0098) and 59% compared with IMRT (p = 0.0020), thus all patients were offered treatment with PT. PT provided the lowest mean dose to the heart, lungs, and breasts for all 10 patients compared with either 3D-CRT or IMRT. The median difference in the OAR mean dose reduction with PT compared with 3D-CRT were 10.4 Gy/CGE for heart; 5.5 Gy/CGE for lung; 0.9 Gy/CGE for breast; 8.3 Gy/CGE for esophagus; and 4.1 Gy/CGE for thyroid. The median differences for mean OAR dose reduction for PT compared with IMRT were 4.3 Gy/CGE for heart, 3.1 Gy/CGE for lung, 1.4 Gy/CGE for breast, 2.8 Gy/CGE for esophagus, and 2.7 Gy/CGE for thyroid. Conclusions: All 10 patients benefitted from dose reductions to OARs with PT compared with either 3D-CRT or IMRT. It is anticipated that these reductions in dose to OAR will translate into lower rates of late complications, but long-term follow-up on this Phase II INRT study is needed.

  15. [Dosimetric comparison of different techniques for external beam accelerated partial breast irradiation].

    PubMed

    Stelczer, Gábor; Major, Tibor; Mészáros, Norbert; Polgár, Csaba; Pesznyák, Csilla

    2016-11-29

    The aim of this article is to evaluate and compare four different radiotherapy techniques of accelerated partial breast irradiation (APBI) considering planning quality, dosimetric and practical aspects. The investigated techniques are three dimensional conformal radiotherapy (3D-CRT), "step and shoot" (SS) and "sliding window" (SW) intensity-modulated radiotherapy, intensity-modulated arc therapy (RA). CT scans of 10 patients previously treated with APBI were selected for the study. Surgical clips were placed on the borders of the tumour bed during breast conserving surgery. Target volume (PTV) was defined as enlarged CTV, which was created from the tumour bed through volume expansion using individual margins. Planning objectives were set up according to the international recommendations. Non-coplanar fields were used only for the 3D-CRT plans. For each plan homogeneity, conformity and plan quality indices were calculated from volumetric and dosimetric parameters of target volumes and organs at risk. The total monitor units and feasibility were also investigated. There was no significant difference in the coverage of the target volume by the prescribed dose between the techniques. SW plans were significantly more homogeneous (HI=0.033) than the 3D-CRT (HI=0.057) and the RA (HI=0.073) plans. The homogeneity of the SS technique (HI=0.053) did not differ significantly compared to others. The conformity of the 3D-CRT technique was significantly worse (CN=0.62) than that of SS (CN=0.85), SW (CN=0.85) and RA (CN=0.86) plans. There was a significant difference between RA (29.4%) and 3D-CRT (44.1%) and SW (35.6%) plans in the V50% of the ipsilateral breast. Mean V10% of the ipsilateral lung in 3D-CRT (10.1%) plans was significantly lower than in SS (34.3%), SW (34.3%) and RA (35.3%) plans. 3D-CRT technique provided the best heart protection. The shortest treatment times were achieved with RA technique. Good target volume coverage and tolerable dose to the organs at risk

  16. [Radiotherapy of benign intracranial tumors].

    PubMed

    Delannes, M; Latorzeff, I; Chand, M E; Huchet, A; Dupin, C; Colin, P

    2016-09-01

    Most of the benign intracranial tumors are meningiomas, vestibular schwannomas, pituitary adenomas, craniopharyngiomas, and glomus tumors. Some of them grow very slowly, and can be observed without specific treatment, especially if they are asymptomatic. Symptomatic or growing tumors are treated by surgery, which is the reference treatment. When surgery is not possible, due to the location of the lesion, or general conditions, radiotherapy can be applied, as it is if there is a postoperative growing residual tumor, or a local relapse. Indications have to be discussed in polydisciplinary meetings, with precise evaluation of the benefit and risks of the treatments. The techniques to be used are the most modern ones, as multimodal imaging and image-guided radiation therapy. Stereotactic treatments, using fractionated or single doses depending on the size or the location of the tumors, are commonly realized, to avoid as much a possible the occurrence of late side effects.

  17. Radiotherapy for Pancreatic Neuroendocrine Tumors

    SciTech Connect

    Contessa, Joseph N.; Griffith, Kent A.; Wolff, Elizabeth; Ensminger, William; Zalupski, Mark; Ben-Josef, Edgar

    2009-11-15

    Purpose: Pancreatic neuroendocrine tumors (PNTs) are rare malignant neoplasms considered to be resistant to radiotherapy (RT), although data on efficacy are scarce. We reviewed our institutional experience to further delineate the role of RT for patients with PNTs. Methods and Materials: Between 1986 and 2006, 36 patients with PNTs were treated with RT to 49 sites. Of these 36 patients, 23 had radiographic follow-up data, which were used to determine the tumor response rate and freedom from local progression. Long-term toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events. Results: The overall response rate to RT was 39% (13% complete response, 26% partial response, 56% stable disease, and 4% progressive disease). A significant difference in the freedom from local progression between the groups receiving either greater than or less than the median 2 Gy/fraction biologically equivalent dose of 49.6 Gy was found, with all radiographic progression occurring in patients who had received <=32 Gy. The actuarial 3-year local freedom from progression rate was 49%. Palliation was achieved in 90% of patients, with either improvement or resolution of symptoms after RT. Of 35 patients, 33 had metastatic disease at their referral for RT, and the median overall survival for this patient population was 2 years. Three long-term Grade 3 or greater toxicities were recorded. Conclusion: RT is an effective modality for achieving local control in patients with PNTs. RT produces high rates of symptomatic palliation and freedom from local progression. Prospective trials of radiotherapy for PNTs are warranted.

  18. Continuous Arc Rotation of the Couch Therapy for the Delivery of Accelerated Partial Breast Irradiation: A Treatment Planning Analysis

    SciTech Connect

    Shaitelman, Simona F.; Kim, Leonard H.; Yan Di; Martinez, Alvaro A.; Vicini, Frank A.; Grills, Inga S.

    2011-07-01

    Purpose: We present a novel form of arc therapy: continuous arc rotation of the couch (C-ARC) and compare its dosimetry with three-dimensional conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), and volumetric-modulated arc therapy (VMAT) for accelerated partial breast irradiation (APBI). C-ARC, like VMAT, uses a modulated beam aperture and dose rate, but with the couch, not the gantry, rotating. Methods and Materials: Twelve patients previously treated with APBI using 3D-CRT were replanned with (1) C-ARC, (2) IMRT, and (3) VMAT. C-ARC plans were designed with one medial and one lateral arc through which the couch rotated while the gantry was held stationary at a tangent angle. Target dose coverage was normalized to the 3D-CRT plan. Comparative endpoints were dose to normal breast tissue, lungs, and heart and monitor units prescribed. Results: Compared with 3D-CRT, C-ARC, IMRT, and VMAT all significantly reduced the ipsilateral breast V50% by the same amount (mean, 7.8%). Only C-ARC and IMRT plans significantly reduced the contralateral breast maximum dose, the ipsilateral lung V5Gy, and the heart V5%. C-ARC used on average 40%, 30%, and 10% fewer monitor units compared with 3D-CRT, IMRT, and VMAT, respectively. Conclusions: C-ARC provides improved dosimetry and treatment efficiency, which should reduce the risks of toxicity and secondary malignancy. Its tangent geometry avoids irradiation of critical structures that is unavoidable using the en face geometry of VMAT.

  19. Intraoperative Radiotherapy in Childhood Malignant Astrocytoma

    PubMed Central

    Rana, Sohail R.; Haddy, Theresa B.; Ashayeri, Ebrahim; Goldson, Alfred L.

    1984-01-01

    A 12-year-old black male patient with glioblastoma multiforme was treated with intraoperative radiotherapy followed by conventional external beam radiation and chemotherapy. The authors' clinical experience with these therapeutic measures is discussed. PMID:6330375

  20. Historical aspects of heavy ion radiotherapy

    SciTech Connect

    Raju, M.R.

    1995-03-01

    This paper presents historical developments of heavy-ion radiotherapy including discussion of HILAC and HIMAC and discussion of cooperation between Japan and the United States, along with personal reflections.

  1. Imaging Instrumentation and Techniques for Precision Radiotherapy

    NASA Astrophysics Data System (ADS)

    Parodi, Katia; Parodi, Katia; Thieke, Christian; Thieke, Christian

    Over the last decade, several technological advances have considerably improved the achievable precision of dose delivery in radiation therapy. Clinical exploitation of the superior tumor-dose conformality offered by modern radiotherapy techniques like intensity-modulated radiotherapy and ion beam therapy requires morphological and functional assessment of the tumor during the entire therapy chain from treatment planning to beam application and treatment response evaluation. This chapter will address the main rationale and role of imaging in state-of-the-art external beam radiotherapy. Moreover, it will present the status of novel imaging instrumentation and techniques being nowadays introduced in clinical use or still under development for image guidance and, ultimately, dose guidance of precision radiotherapy.

  2. [Conformal radiotherapy for vertebral bone metastasis].

    PubMed

    Faivre, J C; Py, J F; Vogin, G; Martinage, G; Salleron, J; Royer, P; Grandgirard, N; Pasquier, D; Thureau, S

    2016-10-01

    Analgesic external beam radiation therapy is a standard of care for patients with uncomplicated painful bone metastases and/or prevention of bone complications. In case of fracture risk, radiation therapy is performed after surgery in a consolidation of an analgesic purpose and stabilizing osteosynthesis. Radiotherapy is mandatory after vertebroplasty or kyphoplasty. Spinal cord compression - the only emergency in radiation therapy - is indicated postoperatively either exclusively for non surgical indication. Analgesic re-irradiation is possible in the case of insufficient response or recurrent pain after radiotherapy. Metabolic radiation, bisphosphonates or denosumab do not dissuade external radiation therapy for pain relief. Systemic oncological treatments can be suspended with a period of wash out given the risk of radiosensitization or recall phenomenon. Better yet, the intensity modulated radiotherapy and stereotactic radiotherapy can be part of a curative strategy for oligometastatic patients and suggest new treatment prospects.

  3. [Hopes of high dose-rate radiotherapy].

    PubMed

    Fouillade, Charles; Favaudon, Vincent; Vozenin, Marie-Catherine; Romeo, Paul-Henri; Bourhis, Jean; Verrelle, Pierre; Devauchelle, Patrick; Patriarca, Annalisa; Heinrich, Sophie; Mazal, Alejandro; Dutreix, Marie

    2017-03-07

    In this review, we present the synthesis of the newly acquired knowledge concerning high dose-rate irradiations and the hopes that these new radiotherapy modalities give rise to. The results were presented at a recent symposium on the subject.

  4. [Radiotherapy of carcinoma of the salivary glands].

    PubMed

    Servagi-Vernat, S; Tochet, F

    2016-09-01

    Indication, doses, and technique of radiotherapy for salivary glands carcinoma are presented, and the contribution of neutrons and carbon ions. The recommendations for delineation of the target volumes and organs at risk are detailed.

  5. Heavy particle radiotherapy: prospects and pitfalls

    SciTech Connect

    Faju, M.R.

    1980-01-01

    The use of heavy particles in radiotherapy of tumor volumes is examined. Particles considered are protons, helium ions, heavy ions, negative pions, and fast neutrons. Advantages and disadvantages are discussed. (ACR)

  6. Intracranial aneurysm formation after radiotherapy for medulloblastoma

    PubMed Central

    Kamide, Tomoya; Mohri, Masanao; Misaki, Kouichi; Uchiyama, Naoyuki; Nakada, Mitsutoshi

    2016-01-01

    Background: The development of an intracranial aneurysm after radiotherapy is rare but secondary effect of cranial irradiation in a primary disease treatment. Case Description: The patient was a 17-year-old male adolescent who was diagnosed as having a posterior fossa medulloblastoma when he was 8 years old. He had undergone tumor resection with radiotherapy and chemotherapy. A distal posterior inferior cerebellar artery aneurysm was identified by magnetic resonance imaging 8 years after radiotherapy and grew rapidly throughout the next 1 year. The patient underwent microsurgical clipping and was discharged without deficit. Conclusion: This experience demonstrates that physicians caring for patients who have undergone intracranial radiotherapy should carefully consider the possibility of an aneurysmal formation when conducting follow-up imaging. PMID:27999713

  7. [Radiotherapy for small cell lung carcinoma].

    PubMed

    Pourel, N

    2016-10-01

    Radiotherapy for small cell lung carcinoma has known significant improvements over the past 10 years especially through routine use of PET-CT in the initial work-up and contouring before treatment. Prophylactic cranial irradiation remains a standard of care for locally advanced disease and is a subject of controversy for metastatic disease. A new indication for thoracic radiotherapy may soon arise for metastatic disease, still confirmation studies are ongoing.

  8. Blisters - an unusual effect during radiotherapy.

    PubMed

    Höller, U; Schubert, T; Budach, V; Trefzer, U; Beyer, M

    2013-11-01

    The skin reaction to radiation is regularly monitored in order to detect enhanced radiosensitivity of the patient, unexpected interactions (e.g. with drugs) or any inadvertent overdosage. It is important to distinguish secondary disease from radiation reaction to provide adequate treatment and to avoid unnecessary discontinuation of radiotherapy. A case of bullous eruption or blisters during radiotherapy of the breast is presented. Differential diagnoses bullous pemphigoid, pemphigus vulgaris, and bullous impetigo are discussed and treatment described.

  9. Radiotherapy in the treatment of vertebral hemangiomas

    SciTech Connect

    Faria, S.L.; Schlupp, W.R.; Chiminazzo, H. Jr.

    1985-02-01

    Symptomatic vertebral hemangiomas are not common. Although radiotherapy has been used as treatment, the data are sparse concerning total dose, fractionation and results. The authors report nine patients with vertebral hemangioma treated with 3000-4000 rad, 200 rad/day, 5 fractions per week, followed from 6 to 62 months. Seventy-seven percent had complete or almost complete disappearance of the symptoms. Radiotherapy schedules are discussed.

  10. Radiotherapy for Vestibular Schwannomas: A Critical Review

    SciTech Connect

    Murphy, Erin S.; 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 to >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.

  11. Adapting radiotherapy to hypoxic tumours

    NASA Astrophysics Data System (ADS)

    Malinen, Eirik; Søvik, Åste; Hristov, Dimitre; Bruland, Øyvind S.; Rune Olsen, Dag

    2006-10-01

    In the current work, the concepts of biologically adapted radiotherapy of hypoxic tumours in a framework encompassing functional tumour imaging, tumour control predictions, inverse treatment planning and intensity modulated radiotherapy (IMRT) were presented. Dynamic contrast enhanced magnetic resonance imaging (DCEMRI) of a spontaneous sarcoma in the nasal region of a dog was employed. The tracer concentration in the tumour was assumed related to the oxygen tension and compared to Eppendorf histograph measurements. Based on the pO2-related images derived from the MR analysis, the tumour was divided into four compartments by a segmentation procedure. DICOM structure sets for IMRT planning could be derived thereof. In order to display the possible advantages of non-uniform tumour doses, dose redistribution among the four tumour compartments was introduced. The dose redistribution was constrained by keeping the average dose to the tumour equal to a conventional target dose. The compartmental doses yielding optimum tumour control probability (TCP) were used as input in an inverse planning system, where the planning basis was the pO2-related tumour images from the MR analysis. Uniform (conventional) and non-uniform IMRT plans were scored both physically and biologically. The consequences of random and systematic errors in the compartmental images were evaluated. The normalized frequency distributions of the tracer concentration and the pO2 Eppendorf measurements were not significantly different. 28% of the tumour had, according to the MR analysis, pO2 values of less than 5 mm Hg. The optimum TCP following a non-uniform dose prescription was about four times higher than that following a uniform dose prescription. The non-uniform IMRT dose distribution resulting from the inverse planning gave a three times higher TCP than that of the uniform distribution. The TCP and the dose-based plan quality depended on IMRT parameters defined in the inverse planning procedure (fields

  12. Performance of dose calculation algorithms from three generations in lung SBRT: comparison with full Monte Carlo-based dose distributions.

    PubMed

    Ojala, Jarkko J; Kapanen, Mika K; Hyödynmaa, Simo J; Wigren, Tuija K; Pitkänen, Maunu A

    2014-03-06

    The accuracy of dose calculation is a key challenge in stereotactic body radiotherapy (SBRT) of the lung. We have benchmarked three photon beam dose calculation algorithms--pencil beam convolution (PBC), anisotropic analytical algorithm (AAA), and Acuros XB (AXB)--implemented in a commercial treatment planning system (TPS), Varian Eclipse. Dose distributions from full Monte Carlo (MC) simulations were regarded as a reference. In the first stage, for four patients with central lung tumors, treatment plans using 3D conformal radiotherapy (CRT) technique applying 6 MV photon beams were made using the AXB algorithm, with planning criteria according to the Nordic SBRT study group. The plans were recalculated (with same number of monitor units (MUs) and identical field settings) using BEAMnrc and DOSXYZnrc MC codes. The MC-calculated dose distributions were compared to corresponding AXB-calculated dose distributions to assess the accuracy of the AXB algorithm, to which then other TPS algorithms were compared. In the second stage, treatment plans were made for ten patients with 3D CRT technique using both the PBC algorithm and the AAA. The plans were recalculated (with same number of MUs and identical field settings) with the AXB algorithm, then compared to original plans. Throughout the study, the comparisons were made as a function of the size of the planning target volume (PTV), using various dose-volume histogram (DVH) and other parameters to quantitatively assess the plan quality. In the first stage also, 3D gamma analyses with threshold criteria 3%/3mm and 2%/2 mm were applied. The AXB-calculated dose distributions showed relatively high level of agreement in the light of 3D gamma analysis and DVH comparison against the full MC simulation, especially with large PTVs, but, with smaller PTVs, larger discrepancies were found. Gamma agreement index (GAI) values between 95.5% and 99.6% for all the plans with the threshold criteria 3%/3 mm were achieved, but 2%/2 mm

  13. Radiotherapy Treatment Planning for Testicular Seminoma

    SciTech Connect

    Wilder, Richard B.; Buyyounouski, Mark K.; Efstathiou, Jason A.; Beard, Clair J.

    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 radiotherapy 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).

  14. A systematic review of antiproton radiotherapy

    NASA Astrophysics Data System (ADS)

    Bittner, Martin-Immanuel; Grosu, Anca-Ligia; Wiedenmann, Nicole; Wilkens, Jan

    2013-01-01

    Antiprotons have been proposed as possible particles for radiotherapy; over the past years, the renewed interest in the potential biomedical relevance led to an increased research activity. It is the aim of this review to deliver a comprehensive overview regarding the evidence accumulated so far, analysing the background and depicting the current status of antiprotons in radiotherapy. A literature search has been conducted, including major scientific and commercial databases. All articles and a number of relevant conference abstracts published in the respective field have been included in this systematic review. The physical basis of antiproton radiotherapy is complex; however, the characterisation of the energy deposition profile supports its potential use in radiotherapy. Also the dosimetry improved considerably over the past few years. Regarding the biological properties, data on the effects on cells are presented; however, definite conclusions regarding the relative biological effectiveness cannot be made at the moment and radiobiological evidence of enhanced effectiveness remains scarce. In addition, there is new evidence supporting the potential imaging properties, for example for online dose verification. Clinical settings which might profit from the use of antiprotons have been further tracked. Judging from the evidence available so far, clinical constellations requiring optimal sparing in the entrance region of the beam and re-irradiations might profit most from antiproton radiotherapy. While several open questions remain to be answered, first steps towards a thorough characterisation of this interesting modality have been made.

  15. A systematic review of antiproton radiotherapy

    NASA Astrophysics Data System (ADS)

    Bittner, Martin-Immanuel; Grosu, Anca-Ligia; Wiedenmann, Nicole; Wilkens, Jan

    2014-01-01

    Antiprotons have been proposed as possible particles for radiotherapy; over the past years, the renewed interest in the potential biomedical relevance led to an increased research activity. It is the aim of this review to deliver a comprehensive overview regarding the evidence accumulated so far, analysing the background and depicting the current status of antiprotons in radiotherapy. A literature search has been conducted, including major scientific and commercial databases. All articles and a number of relevant conference abstracts published in the respective field have been included in this systematic review. The physical basis of antiproton radiotherapy is complex; however, the characterisation of the energy deposition profile supports its potential use in radiotherapy. Also the dosimetry improved considerably over the past few years. Regarding the biological properties, data on the effects on cells are presented; however, definite conclusions regarding the relative biological effectiveness cannot be made at the moment and radiobiological evidence of enhanced effectiveness remains scarce. In addition, there is new evidence supporting the potential imaging properties, for example for online dose verification. Clinical settings which might profit from the use of antiprotons have been further tracked. Judging from the evidence available so far, clinical constellations requiring optimal sparing in the entrance region of the beam and re-irradiations might profit most from antiproton radiotherapy. While several open questions remain to be answered, first steps towards a thorough characterisation of this interesting modality have been made.

  16. Fiducial marker guided prostate radiotherapy: a review.

    PubMed

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

    2016-12-01

    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.

  17. Differences in breast tissue oxygenation following radiotherapy.

    PubMed

    Dornfeld, Ken; Gessert, Charles E; Renier, Colleen M; McNaney, David D; Urias, Rodolfo E; Knowles, Denise M; Beauduy, Jean L; Widell, Sherry L; McDonald, Bonita L

    2011-08-01

    Tissue perfusion and oxygenation changes following radiotherapy may result from and/or contribute to the toxicity of treatment. Breast tissue oxygenation levels were determined in the treated and non-treated breast 1 year after radiotherapy for breast conserving treatment. Transcutaneous oxygenation varied between subjects in both treated and non-treated breast. Subjects without diabetes mellitus (n=16) had an average oxygenation level of 64.8 ± 19.9mmHg in the irradiated breast and an average of 72.3 ± 18.1mmHg (p=0.018) at the corresponding location in the control breast. Patients with diabetes (n=4) showed a different oxygenation pattern, with lower oxygenation levels in control tissue and no decrease in the irradiated breast. This study suggests oxygenation levels in normal tissues vary between patients and may respond differently after radiotherapy.

  18. Oral verrucous carcinoma. Treatment with radiotherapy

    SciTech Connect

    Nair, M.K.; Sankaranarayanan, R.; Padmanabhan, T.K.; Madhu, C.S.

    1988-02-01

    Fifty-two cases of oral verrucous carcinoma treated with radiotherapy at the Regional Cancer Centre, Trivandrum, Kerala, India in 1982 were evaluated to determine the distribution within the oral cavity, clinical extent, and effectiveness of radiotherapy in controlling the disease. The most common site was the buccal mucosa. Fifty percent of the patients had clinically negative regional lymph nodes and 33% were in earlier stages (T1, T2, N0, and M0). The overall 3-year no evidence of disease (NED) survival rate was 44%. The 3-year NED survival rate with radium implant was 86%. We cannot comment on anaplastic transformation after radiotherapy because our treatment failures have not been subjected for biopsy concerning this matter. Because the results are comparable with those of well-differentiated squamous cell carcinoma, we think that the treatment policies advocated for oral squamous cell carcinoma are also applicable to oral verrucous carcinoma.

  19. [Good practice of image-guided radiotherapy].

    PubMed

    de Crevoisier, R; Créhange, G; Castelli, J; Lafond, C; Delpon, G

    2015-10-01

    Image-guided radiotherapy (IGRT) aims to take into account the anatomical variations occurring during the course of radiotherapy, by direct or indirect visualization of the target volume followed by a corrective action. The movements of the target, or at least the set-up errors are corrected by moving the treatment table, corresponding to the simplest and most validated IGRT modality in a standard practice. The deformations of the target volume and organs at risk are however much more common, and unfortunately much more complicated to consider, requiring multiple planning before or during the treatment, corresponding to the adaptive radiotherapy strategies. The planning target volume must be carefully chosen according to these anatomic variations. This article reviews the modalities of IGRT, standard or under evaluation, according to the different tumour sites.

  20. 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.

  1. One hundred years of radiotherapy in Turkey.

    PubMed

    Dincer, M; Kuter, S

    2001-10-01

    The study and practice of radiology in Turkey began in 1897, only 2 years after the discovery of X-rays. A simple X-ray machine was constructed in Istanbul, consisting of a Crookes tube, a Ruhmkorff coil, and a home-made battery. This machine was first used on wounded soldiers, for diagnostic purposes. The first report of X-rays being used therapeutically in Turkey was published in a national journal in 1904. By 1933, the most up-to-date radiotherapy equipment of the time had been installed in every major city in the country. Innovative radiotherapy techniques, such as rotational treatment, were also being tried in 1930s. Today, there are 45 radiotherapy centres in Turkey, and 400 radiation oncologists and 80 medical physicists practise there.

  2. Pelvic radiotherapy and sexual function in women

    PubMed Central

    Froeding, Ligita Paskeviciute

    2015-01-01

    Background During the past decade there has been considerable progress in developing new radiation methods for cancer treatment. Pelvic radiotherapy constitutes the primary or (neo) adjuvant treatment of many pelvic cancers e.g., locally advanced cervical and rectal cancer. There is an increasing focus on late effects and an increasing awareness that patient reported outcomes (PROs) i.e., patient assessment of physical, social, psychological, and sexual functioning provides the most valid information on the effects of cancer treatment. Following cure of cancer allow survivors focus on quality of life (QOL) issues; sexual functioning has proved to be one of the most important aspects of concern in long-term survivors. Methods An updated literature search in PubMed was performed on pelvic radiotherapy and female sexual functioning/dysfunction. Studies on gynaecological, urological and gastrointestinal cancers were included. The focus was on the period from 2010 to 2014, on studies using PROs, on potential randomized controlled trials (RCTs) where female sexual dysfunction (FSD) at least constituted a secondary outcome, and on studies reporting from modern radiotherapy modalities. Results The literature search revealed a few RCTs with FSD evaluated as a PRO and being a secondary outcome measure in endometrial and in rectal cancer patients. Very limited information could be extracted regarding FSD in bladder, vulva, and anal cancer patients. The literature before and after 2010 confirms that pelvic radiotherapy, independent on modality, increases the risk significantly for FSD both compared to data from age-matched healthy control women and compared to data on patients treated by surgery only. There was only very limited data available on modern radiotherapy modalities. These are awaited during the next five years. Several newer studies confirm that health care professionals are still reluctant to discuss treatment induced sexual dysfunction with patients. Conclusions

  3. Meningioma after radiotherapy for Hodgkin's disease.

    PubMed

    Deutsch, M; Rosenstein, M; Figura, J H

    1999-08-01

    The most common second primary tumors after treatment of childhood Hodgkin's disease are leukemia, lymphoma, breast cancer, soft tissue sarcoma, and thyroid cancer. Although intracranial meningioma has been reported after radiotherapy to the scalp for benign conditions and for intracranial primary brain tumors, this appears to be an extremely rare sequelae of treatment for Hodgkin's disease. The authors describe a 15-year-old boy who underwent radiotherapy for Hodgkin's disease and in whom a meningioma developed in the posterior fossa 27 years later.

  4. A novel four-dimensional radiotherapy planning strategy from a tumor-tracking beam's eye view

    NASA Astrophysics Data System (ADS)

    Li, Guang; Cohen, Patrice; Xie, Huchen; Low, Daniel; Li, Diana; Rimner, Andreas

    2012-11-01

    To investigate the feasibility of four-dimensional radiotherapy (4DRT) planning from a tumor-tracking beam's eye view (ttBEV) with reliable gross tumor volume (GTV) delineation, realistic normal tissue representation, high planning accuracy and low clinical workload, we propose and validate a novel 4D conformal planning strategy based on a synthesized 3.5D computed tomographic (3.5DCT) image with a motion-compensated tumor. To recreate patient anatomy from a ttBEV in the moving tumor coordinate system for 4DRT planning (or 4D planning), the centers of delineated GTVs in all phase CT images of 4DCT were aligned, and then the aligned CTs were averaged to produce a new 3.5DCT image. This GTV-motion-compensated CT contains a motionless target (with motion artifacts minimized) and motion-blurred normal tissues (with a realistic temporal density average). Semi-automatic threshold-based segmentation of the tumor, lung and body was applied, while manual delineation was used for other organs at risk (OARs). To validate this 3.5DCT-based 4D planning strategy, five patients with peripheral lung lesions of small size (<5 cm3) and large motion range (1.2-3.5 cm) were retrospectively studied for stereotactic body radiotherapy (SBRT) using 3D conformal radiotherapy planning tools. The 3.5DCT-based 4D plan (3.5DCT plan) with 9-10 conformal beams was compared with the 4DCT-based 4D plan (4DCT plan). The 4DCT plan was derived from multiple 3D plans based on all phase CT images, each of which used the same conformal beam configuration but with an isocenter shift to aim at the moving tumor and a minor beam aperture and weighting adjustment to maintain plan conformality. The dose-volume histogram (DVH) of the 4DCT plan was created with two methods: one is an integrated DVH (iDVH4D), which is defined as the temporal average of all 3D-phase-plan DVHs, and the other (DVH4D) is based on the dose distribution in a reference phase CT image by dose warping from all phase plans using the

  5. Effects of docetaxel plus three-dimensional conformal radiation therapy on microvessel density and apoptosis expression in local advanced squamous non-small-cell lung cancer.

    PubMed

    Zhai, X J; Cheng, H R; Long, H L; Mao, W K; Cao, L; Xiao, B R; Li, R Q

    2015-05-22

    We examined the effects of weekly single-agent docetaxel plus three-dimensional conformal radiation therapy (3D-CRT) on apoptotic index (AI) and microvessel density (MVD) in local advanced non-small-cell lung squamous cancer patients and analyzed the correlation of MVD, AI, and 50% tumor shrinkage time (T0.5) The molecular mechanism of docetaxel radiosensitization was investigated. Sixty untreated patients with stage IIIA or IIIB lung squamous cancer were enrolled and randomly divided into two groups: observation (N = 30; 3D-CRT + docetaxel + adjuvant chemotherapy) and control (N = 30; 3D-CRT + adjuvant chemotherapy). From day 1 radiotherapy, the observation group received intravenous docetaxel (36 mg/m(2)) once weekly for 6 weeks. Post-radiotherapy, chemotherapy of docetaxel combined with cisplatin lasted 4-6 cycles in both groups. Before radiotherapy and within 24 h after radiotherapy (20 Gy), bronchoscopic biopsy was performed twice at the same site. To analyze the MVD of tumor specimens with immunohistochemical staining . The AI of lung cancer cells was assessed with TUNEL assay, T0.5 values were calculated. The observation group had significantly lower MVD than the control group (P < 0.05). AI significantly increased before and after treatment in the observation group compared with the control group (P < 0.05). The decreased MVD values negatively correlated with T0.5 values (r = -0.624, P < 0.05), whereas the increased AI values did not correlate with the T0.5 values. Docetaxel radiosensitization may occur by decrease in MVD and increase in AI values. Weekly single-agent docetaxel plus 3D-CRT can improve prognosis and quality of life in local advanced non-small-cell lung squamous cancer patients.

  6. Verification of Patient Positioning in Proton Therapy based on Digital X-ray Images

    NASA Astrophysics Data System (ADS)

    Shipulin, K. N.; Kolonuto, P. E.; Mytsin, G. V.

    2007-11-01

    This paper describes a technique to verify the position of a target (tumor) in relation to a proton beam in the 3D conformal proton radiotherapy used at the Medico-Technical Complex of the JINR Dubna.

  7. Verification of Patient Positioning in Proton Therapy based on Digital X-ray Images

    SciTech Connect

    Shipulin, K. N.; Kolonuto, P. E.; Mytsin, G. V.

    2007-11-26

    This paper describes a technique to verify the position of a target (tumor) in relation to a proton beam in the 3D conformal proton radiotherapy used at the Medico-Technical Complex of the JINR Dubna.

  8. Radiotherapy in the management of early breast cancer

    SciTech Connect

    Wang, Wei

    2013-03-15

    Radiotherapy is an indispensible part of the management of all stages of breast cancer. In this article, the common indications for radiotherapy in the management of early breast cancer (stages 0, I, and II) are reviewed, including whole-breast radiotherapy as part of breast-conserving treatment for early invasive breast cancer and pre-invasive disease of ductal carcinoma in situ, post-mastectomy radiotherapy, locoregional radiotherapy, and partial breast irradiation. Key clinical studies that underpin our current practice are discussed briefly.

  9. The Leicester radiotherapy bite block: an aid to head and neck radiotherapy.

    PubMed

    Hollows, P; Hayter, J P; Vasanthan, S

    2001-02-01

    We describe the construction of a custom-made bite block to be used during external beam radiotherapy to the oral cavity. The bite block is made with standard maxillofacial prosthetic techniques and materials. The design allows accurate and reproducible positioning of the perioral tissues to aid planning of radiotherapy and treatment. The compressibility of this device improves comfort for the patient, while it is in use.

  10. A frequency-based approach to locate common structure for 2D-3D intensity-based registration of setup images in prostate radiotherapy

    SciTech Connect

    Munbodh, Reshma; Chen Zhe; Jaffray, David A.; Moseley, Douglas J.; Knisely, Jonathan P. S.; Duncan, James S.

    2007-07-15

    In many radiotherapy clinics, geometric uncertainties in the delivery of 3D conformal radiation therapy and intensity modulated radiation therapy of the prostate are reduced by aligning the patient's bony anatomy in the planning 3D CT to corresponding bony anatomy in 2D portal images acquired before every treatment fraction. In this paper, we seek to determine if there is a frequency band within the portal images and the digitally reconstructed radiographs (DRRs) of the planning CT in which bony anatomy predominates over non-bony anatomy such that portal images and DRRs can be suitably filtered to achieve high registration accuracy in an automated 2D-3D single portal intensity-based registration framework. Two similarity measures, mutual information and the Pearson correlation coefficient were tested on carefully collected gold-standard data consisting of a kilovoltage cone-beam CT (CBCT) and megavoltage portal images in the anterior-posterior (AP) view of an anthropomorphic phantom acquired under clinical conditions at known poses, and on patient data. It was found that filtering the portal images and DRRs during the registration considerably improved registration performance. Without filtering, the registration did not always converge while with filtering it always converged to an accurate solution. For the pose-determination experiments conducted on the anthropomorphic phantom with the correlation coefficient, the mean (and standard deviation) of the absolute errors in recovering each of the six transformation parameters were {theta}{sub x}:0.18(0.19) deg., {theta}{sub y}:0.04(0.04) deg., {theta}{sub z}:0.04(0.02) deg., t{sub x}:0.14(0.15) mm, t{sub y}:0.09(0.05) mm, and t{sub z}:0.49(0.40) mm. The mutual information-based registration with filtered images also resulted in similarly small errors. For the patient data, visual inspection of the superimposed registered images showed that they were correctly aligned in all instances. The results presented in this

  11. SU-E-J-93: Development of Pre-Contoured Human Model Library in DICOM-RT Format for the Epidemiological Study of the Radiotherapy Patients

    SciTech Connect

    Pyakuryal, A; Lee, C; Lee, C; Pelletier, C; Jung, J

    2015-06-15

    Purpose: Prior to 3D conformal radiation therapy planning, patient anatomy information was mostly limited to 2D beams-eye-view from the conventional simulator. To analyze the outcomes of such treatments for radiation late effects, 3D computational human models are often used in commercial treatment planning systems (TPSs). However, several underlying difficulties such as time-consuming manual delineation procedures of a large number of structures in the model have always limited its applications. Primary objective of this work was to develop a human model library for the epidemiological study by converting 3D-surface model organs to DICOM-RT format (DICOM-RT structure) using an in-house built software. We converted the ICRP reference human models to DICOM-RT models, which can be readily adopted for various dose calculations. Methods: MATLAB based code were utilized to convert the contour drawings extracted in text-format from the 3D graphic-tool, Rhinoceros into DICOM-RT structure format for 50 different organs of each model using a 16GB dual-core processor. The conversion periods were measured for each DICOM-RT models, and the reconstructed structure volumes were validated against the original 3D-surface models in the TPS. Ten reference hybrid whole-body models (8-pediatric and 2-adults) were automatically processed to create DICOM-RT computational human model library. Results: Mean contour conversion period was found to be 580 (N=2) and 394.5 (N=8) seconds for 50 organs in the adult and pediatric models respectively. A good agreement for large organs (NRMSD <1.0%) and small organs (NRMSD <7.7%) was also observed between the original volumes and corresponding DICOM-RT structure volumes of the organs. Conclusion: The ICRP reference human models were converted into DICOM-RT format to support the epidemiological study using a large cohort of conventional radiotherapy patients. Due to its DICOM-compatibility, the library may be implemented to many other different

  12. 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.

  13. 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

  14. 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

  15. Radiotherapy for inverted papilloma: a case report.

    PubMed

    Levendag, P C; Annyas, A A; Escajadillo, J R; Elema, J D

    1984-06-01

    Inverted papilloma is an infrequent tumour of the nasal cavity and paranasal sinuses associated with controversy. The incidence of carcinoma in situ associated with inverted papilloma, has not been very well documented until now. Therefore, we present a case report characterized by an aggressive clinical behaviour, treated by extensive surgery and ultimately controlled by radiotherapy.

  16. Results of radiotherapy for Peyronie's disease

    SciTech Connect

    Niewald, Marcus . E-mail: ramnie@uniklinikum-saarland.de; Wenzlawowicz, Knut v.; Fleckenstein, Jochen; Wisser, Lothar; Derouet, Harry; Ruebe, Christian

    2006-01-01

    Purpose: To retrospectively review the results of radiotherapy for Peyronie's disease. Patients and Methods: In the time interval 1983-2000, 154 patients in our clinic were irradiated for Peyronie's disease. Of those, 101 had at least one complete follow-up data set and are the subject of this study. In the majority of patients, penis deviation was between 30 and 50{sup o}, there were one or two indurated foci with a diameter between 5 and 15 mm. Pain was recorded in 48/92 patients. Seventy-two of the 101 patients received radiotherapy with a total dose of 30 Gy, and 25 received 36 Gy in daily fractions of 2.0 Gy. The remaining patients received the following dosage: 34 Gy (1 patient), 38-40 Gy (3 patients). Mean duration of follow-up was 5 years. Results: The best results ever at any time during follow-up were an improvement of deviation in 47%, reduction of number of foci in 32%, reduction of size of foci in 49%, and less induration in 52%. Approximately 50% reported pain relief after radiotherapy. There were 28 patients with mild acute dermatitis and only 4 patients with mild urethritis. There were no long-term side effects. Conclusion: Our results compare well with those of other studies in the literature. In our patient cohort, radiotherapy was an effective therapy option with only very rare and mild side effects.

  17. Neo-adjuvant radiotherapy in rectal cancer

    PubMed Central

    Glimelius, Bengt

    2013-01-01

    In rectal cancer treatment, attention has focused on the local primary tumour and the regional tumour cell deposits to diminish the risk of a loco-regional recurrence. Several large randomized trials have also shown that combinations of surgery, radiotherapy and chemotherapy have markedly reduced the risk of a loco-regional recurrence, but this has not yet had any major influence on overall survival. The best results have been achieved when the radiotherapy has been given preoperatively. Preoperative radiotherapy improves loco-regional control even when surgery has been optimized to improve lateral clearance, i.e., when a total mesorectal excision has been performed. The relative reduction is then 50%-70%. The value of radiotherapy has not been tested in combination with more extensive surgery including lateral lymph node clearance, as practised in some Asian countries. Many details about how the radiotherapy is performed are still open for discussion, and practice varies between countries. A highly fractionated radiation schedule (5 Gy × 5), proven efficacious in many trials, has gained much popularity in some countries, whereas a conventionally fractionated regimen (1.8-2.0 Gy × 25-28), often combined with chemotherapy, is used in other countries. The additional therapy adds morbidity to the morbidity that surgery causes, and should therefore be administered only when the risk of loco-regional recurrence is sufficiently high. The best integration of the weakest modality, to date the drugs (conventional cytotoxics and biologicals) is not known. A new generation of trials exploring the best sequence of treatments is required. Furthermore, there is a great need to develop predictors of response, so that treatment can be further individualized and not solely based upon clinical factors and anatomic imaging. PMID:24379566

  18. A comparative analysis of 3D conformal deep inspiratory-breath hold and free-breathing intensity-modulated radiation therapy for left-sided breast cancer.

    PubMed

    Reardon, Kelli A; Read, Paul W; Morris, Monica M; Reardon, Michael A; Geesey, Constance; Wijesooriya, Krishni

    2013-01-01

    Patients undergoing radiation for left-sided breast cancer have increased rates of coronary artery disease. Free-breathing intensity-modulated radiation therapy (FB-IMRT) and 3-dimensional conformal deep inspiratory-breath hold (3D-DIBH) reduce cardiac irradiation. The purpose of this study is to compare the dose to organs at risk in FB-IMRT vs 3D-DIBH for patients with left-sided breast cancer. Ten patients with left-sided breast cancer had 2 computed tomography scans: free breathing and voluntary DIBH. Optimization of the IMRT plan was performed on the free-breathing scan using 6 noncoplanar tangential beams. The 3D-DIBH plan was optimized on the DIBH scan and used standard tangents. Mean volumes of the heart, the left anterior descending coronary artery (LAD), the total lung, and the right breast receiving 5% to 95% (5% increments) of the prescription dose were calculated. Mean volumes of the heart and the LAD were lower (p<0.05) in 3D-DIBH for volumes receiving 5% to 80% of the prescription dose for the heart and 5% for the LAD. Mean dose to the LAD and heart were lower in 3D-DIBH (p≤0.01). Mean volumes of the total lung were lower in FB-IMRT for dose levels 20% to 75% (p<0.05), but mean dose was not different. Mean volumes of the right breast were not different for any dose; however, mean dose was lower for 3D-DIBH (p = 0.04). 3D-DIBH is an alternative approach to FB-IMRT that provides a clinically equivalent treatment for patients with left-sided breast cancer while sparing organs at risk with increased ease of implementation.

  19. A comparative analysis of 3D conformal deep inspiratory–breath hold and free-breathing intensity-modulated radiation therapy for left-sided breast cancer

    SciTech Connect

    Reardon, Kelli A.; Read, Paul W.; Morris, Monica M.; Reardon, Michael A.; Geesey, Constance; Wijesooriya, Krishni

    2013-07-01

    Patients undergoing radiation for left-sided breast cancer have increased rates of coronary artery disease. Free-breathing intensity-modulated radiation therapy (FB-IMRT) and 3-dimensional conformal deep inspiratory–breath hold (3D-DIBH) reduce cardiac irradiation. The purpose of this study is to compare the dose to organs at risk in FB-IMRT vs 3D-DIBH for patients with left-sided breast cancer. Ten patients with left-sided breast cancer had 2 computed tomography scans: free breathing and voluntary DIBH. Optimization of the IMRT plan was performed on the free-breathing scan using 6 noncoplanar tangential beams. The 3D-DIBH plan was optimized on the DIBH scan and used standard tangents. Mean volumes of the heart, the left anterior descending coronary artery (LAD), the total lung, and the right breast receiving 5% to 95% (5% increments) of the prescription dose were calculated. Mean volumes of the heart and the LAD were lower (p<0.05) in 3D-DIBH for volumes receiving 5% to 80% of the prescription dose for the heart and 5% for the LAD. Mean dose to the LAD and heart were lower in 3D-DIBH (p≤0.01). Mean volumes of the total lung were lower in FB-IMRT for dose levels 20% to 75% (p<0.05), but mean dose was not different. Mean volumes of the right breast were not different for any dose; however, mean dose was lower for 3D-DIBH (p = 0.04). 3D-DIBH is an alternative approach to FB-IMRT that provides a clinically equivalent treatment for patients with left-sided breast cancer while sparing organs at risk with increased ease of implementation.

  20. MED-3DMC: a new tool to generate 3D conformation ensembles of small molecules with a Monte Carlo sampling of the conformational space.

    PubMed

    Sperandio, Olivier; Souaille, Marc; Delfaud, François; Miteva, Maria A; Villoutreix, Bruno O

    2009-04-01

    Obtaining an efficient sampling of the low to medium energy regions of a ligand conformational space is of primary importance for getting insight into relevant binding modes of drug candidates, or for the screening of rigid molecular entities on the basis of a predefined pharmacophore or for rigid body docking. Here, we report the development of a new computer tool that samples the conformational space by using the Metropolis Monte Carlo algorithm combined with the MMFF94 van der Waals energy term. The performances of the program have been assessed on 86 drug-like molecules that resulted from an ADME/tox profiling applied on cocrystalized small molecules and were compared with the program Omega on the same dataset. Our program has also been assessed on the 85 molecules of the Astex diverse set. Both test sets show convincing performance of our program at sampling the conformational space.

  1. Technical advances in external radiotherapy for hepatocellular carcinoma

    PubMed Central

    Park, Shin-Hyung; Kim, Jae-Chul; Kang, Min Kyu

    2016-01-01

    Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular carcinoma (HCC). Currently, more advanced techniques, including intensity-modulated radiotherapy (IMRT), stereotactic ablative body radiotherapy (SABR), and charged particle therapy, are used for the treatment of HCC. IMRT can escalate the tumor dose while sparing the normal tissue even though the tumor is large or located near critical organs. SABR can deliver a very high radiation dose to small HCCs in a few fractions, leading to high local control rates of 84%-100%. Various advanced imaging modalities are used for radiotherapy planning and delivery to improve the precision of radiotherapy. These advanced techniques enable the delivery of high dose radiotherapy for early to advanced HCCs without increasing the radiation-induced toxicities. However, as there have been no effective tools for the prediction of the response to radiotherapy or recurrences within or outside the radiation field, future studies should focus on selecting the patients who will benefit from radiotherapy. PMID:27621577

  2. Accelerated Partial Breast Irradiation: What is Dosimetric Effect of Advanced Technology Approaches?

    SciTech Connect

    Moran, Jean M. Ben-David, Merav A.; Marsh, Robin B.; Balter, James M.; Griffith, Kent A.; Hayman, James A.; Pierce, Lori J.

    2009-09-01

    Purpose: The present treatment planning study compared whole breast radiotherapy (WBRT) to accelerated partial breast irradiation (APBI) for different external beam techniques and geometries (e.g., free breathing [FB] and deep inspiration breath hold [DIBH]). Methods and Materials: After approval by our institutional review board, a treatment planning study was performed of 10 patients with left-sided Stage 0-I breast cancer enrolled in a Phase I-II study of APBI using intensity-modulated radiotherapy (IMRT). After lumpectomy, patients underwent planning computed tomography scans during FB and using an active breathing control device at DIBH. For the FB geometry, standard WBRT and three-dimensional conformal radiotherapy (3D-CRT) APBI plans were created. For the DIBH geometry with active breathing control, WBRT, 3D-CRT, and IMRT APBI plans were created. Results: All APBI techniques had excellent planning target volume coverage. The maximal planning target volume dose was reduced from 116% of the prescription dose to 108% with the IMRT(DIBH) APBI plan. The maximal heart dose was >30 Gy for the WBRT techniques, 8.2 Gy for 3D-CRT(FB), and <5.0 Gy for 3D-CRT(DIBH) and IMRT(DIBH) techniques. The mean left anterior descending artery dose was significantly reduced from 11.4 Gy with WBRT(FB) to 4.2 with WBRT(DIBH) and <2.0 Gy with all APBI techniques. Conclusion: Although planning target volume coverage was acceptable with all techniques, the plans using the DIBH geometry resulted in a marked reduction in the normal tissue dose compared with WBRT planned in the absence of cardiac blocking. Additional study is needed to determine whether these techniques result in clinical benefits.

  3. Second cancers following radiotherapy for cancer

    SciTech Connect

    Curtis, R.E.

    1997-03-01

    The study of second cancer risk after radiotherapy provides a unique opportunity to study carcinogenesis since large groups of humans are deliberately exposed to substantial doses of radiation in order to cure disease. Detailed radiotherapy records for cancer patients allow precise quantification of organ dose, and population-based cancer registries are frequently available to provide access to large groups of patients who are closely followed for long periods. Moreover, cancer patients treated with surgery alone (no radiation) are frequently available to serve as a non-irradiated comparison group. New information can be provided on relatively insensitive organs, and low dose exposures in the range of scientific interest are received by organs outside the radiation treatment fields. This paper will review several recently completed studies that characterize the risk of radiation-induced second cancers. Emphasis will be given to studies providing new information on the dose-response relationship of radiation-induced leukemia, breast cancer and lung cancer.

  4. [Radiotherapy as primary treatment for chemodectoma?].

    PubMed

    Verniers, D; Van Limbergen, E; Leysen, J; Ostyn, F; Segers, A

    1990-01-01

    Chemodectomas are slowly growing tumours originating in the chemoreceptor bodies. The diagnosis is based on typical clinical symptoms and radiological investigation. CT scanning with contrast enhancement permits to establish diagnosis in most cases and gives a correct idea of tumour size, tumour extension, displacement of arteries and bone destruction. Small tympanic chemodectomas are successfully managed by surgery, without causing additional cranial nerve palsies. Surgery of larger lesions is frequently followed by a high percentage of local recurrence (greater than 50%) and important morbidity (neurologic sequelae). Our present series confirms that these tumours can successfully be treated by radiotherapy. Persisting local control rates can be obtained in more than 90% of cases with moderate doses (45-50 Gy in 5 weeks) of carefully planned radiotherapy.

  5. [Radiotherapy and targeted therapy/immunotherapy].

    PubMed

    Antoni, D; Bockel, S; Deutsch, E; Mornex, F

    2016-10-01

    Thanks to recent advances achieved in oncologic systemic and local ablative treatment, the treatments become more and more efficient in term of local control and overall survival. Thus, the targeted therapies, immunotherapy or stereotactic radiotherapy have modified the management of patients, especially in case of oligometastatic disease. Many questions are raised by these innovations, particularly the diagnosis and management of new side effects or that of the combination of these different treatments, depending on the type of primary tumor. Fundamental data are available, while clinical data are still limited. Ongoing trials should help to clarify the clinical management protocols. This manuscript is a review of the combination of radiotherapy and targeted therapy/immunotherapy.

  6. Perianal Paget disease treated definitively with radiotherapy.

    PubMed

    Mann, J; Lavaf, A; Tejwani, A; Ross, P; Ashamalla, H

    2012-12-01

    Extramammary Paget disease (empd) is a relatively rare cutaneous disorder described as an apocrine gland tumour occurring in both a benign and a malignant form with metastatic potential. The areas of the body affected are the vulva, perianal region, penis, scrotum, perineum, and axilla, all of which contain apocrine glands. When empd affects the perianal region, it is called perianal Paget disease (ppd). All forms of empd, including ppd, are typically treated by wide surgical excision. Perianal Paget disease usually occurs later in life in patients who are often poor surgical candidates, but the available literature is scarce regarding other treatment modalities, including definitive radiotherapy. We contend that ppd can be safely and effectively treated with radiotherapy, and here, we present the case of a 75-year-old woman with ppd who was successfully so treated. A brief review of the literature concerning the diagnosis, natural history, and treatment of ppd is also included.

  7. Proton Radiotherapy for Solid Tumors of Childhood

    PubMed Central

    Cotter, Shane E.; McBride, Sean M.; Yock, Torunn I.

    2012-01-01

    The increasing efficacy of pediatric cancer therapy over the past four decades has produced many long-term survivors that now struggle with serious treatment related morbidities affecting their quality of life. Radiation therapy is responsible for a significant proportion of these late effects, but a relatively new and emerging modality, proton radiotherapy hold great promise to drastically reduce these treatment related late effects in long term survivors by sparing dose to normal tissues. Dosimetric studies of proton radiotherapy compared with best available photon based treatment show significant dose sparing to developing normal tissues. Furthermore, clinical data are now emerging that begin to quantify the benefit in decreased late treatment effects while maintaining excellent cancer control rates. PMID:22417062

  8. Status of radiotherapy in a multidisciplinary cancer board.

    PubMed

    Ichikawa, Mayumi; Nemoto, Kenji; Miwa, Misako; Ohta, Ibuki; Nomiya, Takuma; Yamakawa, Mayumi; Itho, Yuriko; Fukui, Tadahisa; Yoshioka, Takashi

    2014-03-01

    Multidisciplinary cancer boards (CBs) for making cancer treatment decisions have become popular in many countries; however, the status of radiotherapy in CBs and the influence of CBs on radiotherapy decisions have not been studied. To clarify these issues, we reviewed the minutes of our CBs from February 2010 to March 2012, and we classified planned treatments discussed at the CBs into five categories and analyzed decisions concerning radiotherapy in each category. The fraction of cases for which radiotherapy was recommended was 536/757 (71%). These cases included 478 cases (63%) for which radiation therapy was planned and four cases (0.5%) for which radiation therapy was unexpectedly recommended. On the other hand, radiation therapy was canceled in 21 cases (4%) for which radiation therapy had been planned. This study showed that radiotherapy was discussed in many cases at CBs and that CBs have a great influence on decisions concerning radiotherapy.

  9. Postoperative radiotherapy in the management of keloids

    PubMed Central

    Carvajal, Claudia C; Ibarra, Carla M; Arbulo, Douglas L; Russo, Moisés N; Solé, Claudio P

    2016-01-01

    Background The high recurrence rate following keloid resection has generated interest in adjuvant treatments for this disease. Objective This study assesses keloid recurrence when treated with surgery and adjuvant radiotherapy. Methods Retrospective analysis of resected keloids in patients referred to a Chilean radiation oncology centre between 2006 and 2013. Local recurrence was defined as new tissue growth on the surgical scar margin. Results Around103 keloids were analysed in 63 patients treated with 15 Gy in three fraction radiotherapy which was initiated on the same day as the surgery (75% of cases). The median keloid diameter was 6 cm; the most common site was thoracic (22%); the most common cause was prior surgery (35%); 37% caused symptoms, and several (47%) had received prior treatment with corticosteroids (32%), or surgery (30%). The median follow-up was three years, and 94% of recurrences occurred during the first year following treatment. Uni and multivariate analyses showed that an absence of symptoms was a protective factor for recurrence (OR: 0.24), while the time interval from onset to treatment with surgery plus radiotherapy >4.2 years was a risk factor (OR: 2.23). The first year recurrence rate was 32% and stabilised at 32% by the second year with no recurrences after 15 months. Conclusions The combination of surgery and radiotherapy proved to be a good therapeutic alternative in the management of keloids. Our results are similar to those described in the literature for a dose of 15 Gy. Given these results, our centre will implement a new dose escalation protocol to improve future outcomes. PMID:27994646

  10. Radiotherapy equipment--purchase or lease?

    PubMed

    Nisbet, A; Ward, A

    2001-08-01

    Against a background of increasing demand for radiotherapy equipment, this study was undertaken to investigate options for equipment procurement, in particular to compare purchase with lease. The perceived advantages of lease are that equipment can be acquired within budget and cashflow constraints, with relatively low amounts of cash leaving the NHS in the first year, avoiding the necessity of capitalizing the equipment and providing protection against the risk of obsolescence associated with high technology equipment. The perceived disadvantages of leasing are that the Trust does not own the equipment, leasing can be more expensive in revenue terms, the tender process is extended and there may be lease conditions to be met, which may be costly and/or restrictive. There are also a number of technical considerations involved in the leasing of radiotherapy equipment that influence the financial analysis and practical operation of the radiotherapy service. The technical considerations include servicing and planned preventative maintenance, upgrades, spare parts, subsequent purchase of "add ons", modification of equipment, research and development work, commencement of the lease period, return of equipment at the end of the lease period and negotiations at the end of the lease period. A study from Raigmore Hospital, Inverness is described, which involves the procurement of new, state-of-the-art radiotherapy equipment. This provides an overview of the procurement process, including a summary of the advantages and disadvantages of leasing, with the figures from the financial analysis presented and explained. In addition, a detailed description is given of the technical considerations to be taken into account in the financial analysis and negotiation of any lease contract.

  11. Low-Dose Radiotherapy in Indolent Lymphoma

    SciTech Connect

    Rossier, Christine; Schick, Ulrike; Miralbell, Raymond; Mirimanoff, Rene O.; Weber, Damien C.; Ozsahin, Mahmut

    2011-11-01

    Purpose: To assess the response rate, duration of response, and overall survival after low-dose involved-field radiotherapy in patients with recurrent low-grade lymphoma or chronic lymphocytic leukemia (CLL). Methods and Materials: Forty-three (24 women, 19 men) consecutive patients with indolent lymphoma or CLL were treated with a total dose of 4 Gy (2 x 2 Gy) using 6- 18-MV photons. The median age was 73 years (range, 39-88). Radiotherapy was given either after (n = 32; 75%) or before (n = 11; 25%) chemotherapy. The median time from diagnosis was 48 months (range, 1-249). The median follow-up period was 20 months (range, 1-56). Results: The overall response rate was 90%. Twelve patients (28%) had a complete response, 15 (35%) had a partial response, 11 (26%) had stable disease, and 5 (11%) had progressive disease. The median overall survival for patients with a positive response (complete response/partial response/stable disease) was 41 months; for patients with progressive disease it was 6 months (p = 0.001). The median time to in-field progression was 21 months (range, 0-24), and the median time to out-field progression was 8 months (range, 0-40). The 3-year in-field control was 92% in patients with complete response (median was not reached). The median time to in-field progression was 9 months (range, 0.5-24) in patients with partial response and 6 months (range, 0.6-6) in those with stable disease (p < 0.05). Younger age, positive response to radiotherapy, and no previous chemotherapy were the best factors influencing the outcome. Conclusions: Low-dose involved-field radiotherapy is an effective treatment in the management of patients with recurrent low-grade lymphoma or CLL.

  12. Radiation transport in a radiotherapy room

    SciTech Connect

    Agosteo, S.; Para, A.F.; Maggioni, B.

    1995-01-01

    The photoneutron dose equivalent in a linac radio-therapy room and its entrance maze was investigated by means of Monte Carlo simulations under different conditions. Particularly, the effect of neutron absorbers and moderator layers placed on the maze walls was considered. The contribution of prompt gamma rays emitted in absorption reactions of thermal neutrons was also taken into account. The simulation results are compared with some experimental measurements in the therapy room and in the maze. 13 refs., 5 figs., 5 tabs.

  13. 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.

  14. Hypothyroidism After Radiotherapy for Nasopharyngeal Cancer Patients

    SciTech Connect

    Wu, Y.-H.; Wang, H-M.; Chen, Hellen Hi-Wen; Lin, C.-Y.; Chen, Eric Yen-Chao; Fan, K.-H.; Huang, S.-F.; Chen, I-How; Liao, C.-T.; Cheng, Ann-Joy; Chang, Joseph Tung-Chieh

    2010-03-15

    Purpose: The aim of this study was to determine the long-term incidence and possible predictive factors for posttreatment hypothyroidism in nasopharyngeal carcinoma (NPC) patients after radiotherapy. Methods and Materials: Four hundred and eight sequential NPC patients who had received regular annual thyroid hormone surveys prospectively after radiotherapy were included in this study. Median patient age was 47.3 years, and 286 patients were male. Thyroid function was prospectively evaluated by measuring thyroid-stimulating hormone (TSH) and serum free thyroxine (FT4) levels. Low FT4 levels indicated clinical hypothyroidism in this study. Results: With a median follow-up of 4.3 years (range, 0.54-19.7 years), the incidence of low FT4 level was 5.3%, 9.0%, and 19.1% at 3, 5, and 10 years after radiotherapy, respectively. Hypothyroidism was more common with early T stage (p = 0.044), female sex (p = 0.037), and three-dimensional conformal therapy with the altered fractionation technique (p = 0.005) after univariate analysis. N stage, chemotherapy, reirradiation, and neck electron boost did not affect the incidence of hypothyroidism. Younger age and conformal therapy were significant factors that determined clinical hypothyroidism after multivariate analysis. Overall, patients presented with a low FT4 level about 1 year after presenting with an elevated TSH level. Conclusion: Among our study group of NPC patients, 19.1% experienced clinical hypothyroidism by 10 years after treatment. Younger age and conformal therapy increased the risk of hypothyroidism. We suggest routine evaluation of thyroid function in NPC patients after radiotherapy. The impact of pituitary injury should be also considered.

  15. Targeting Radiotherapy to Cancer by Gene Transfer

    PubMed Central

    2003-01-01

    Targeted radionuclide therapy is an alternative method of radiation treatment which uses a tumor-seeking agent carrying a radioactive atom to deposits of tumor, wherever in the body they may be located. Recent experimental data signifies promise for the amalgamation of gene transfer with radionuclide targeting. This review encompasses aspects of the integration of gene manipulation and targeted radiotherapy, highlighting the possibilities of gene transfer to assist the targeting of cancer with low molecular weight radiopharmaceuticals. PMID:12721515

  16. Partial breast radiotherapy with simple teletherapy techniques

    SciTech Connect

    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 × 3 Gy. 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 ≥3.0 cm 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.

  17. Current concepts on imaging in radiotherapy.

    PubMed

    Lecchi, Michela; Fossati, Piero; Elisei, Federica; Orecchia, Roberto; Lucignani, Giovanni

    2008-04-01

    New high-precision radiotherapy (RT) techniques, such as intensity-modulated radiation therapy (IMRT) or hadrontherapy, allow better dose distribution within the target and spare a larger portion of normal tissue than conventional RT. These techniques require accurate tumour volume delineation and intrinsic characterization, as well as verification of target localisation and monitoring of organ motion and response assessment during treatment. These tasks are strongly dependent on imaging technologies. Among these, computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography (US) and positron emission tomography (PET) have been applied in high-precision RT. For tumour volume delineation and characterization, PET has brought an additional dimension to the management of cancer patients by allowing the incorporation of crucial functional and molecular images in RT treatment planning, i.e. direct evaluation of tumour metabolism, cell proliferation, apoptosis, hypoxia and angiogenesis. The combination of PET and CT in a single imaging system (PET/CT) to obtain a fused anatomical and functional dataset is now emerging as a promising tool in radiotherapy departments for delineation of tumour volumes and optimization of treatment plans. Another exciting new area is image-guided radiotherapy (IGRT), which focuses on the potential benefit of advanced imaging and image registration to improve precision, daily target localization and monitoring during treatment, thus reducing morbidity and potentially allowing the safe delivery of higher doses. The variety of IGRT systems is rapidly expanding, including cone beam CT and US. This article examines the increasing role of imaging techniques in the entire process of high-precision radiotherapy.

  18. The role of radiotherapy in veterinary practice.

    PubMed

    Owen, L N

    1975-11-01

    It is common knowledge today that cancer is by no means an incurable disease and therefore it is no longer necessary to propose euthanasia for all inoperable cases of malignant neoplasia. The veterinary surgeon has a duty to inform his client of current methods of treatment, particularly radiotherapy, which may possibly provide a cure or prolong life without pain for several months. This article outlines the availability and usefulness of this important line of treatment.

  19. Glioblastoma multiforme after radiotherapy for acromegaly

    SciTech Connect

    Piatt, J.H. Jr.; Blue, J.M.; Schold, S.C. Jr.; Burger, P.C.

    1983-07-01

    A case of glioblastoma multiforme that occurred 14 years after radiotherapy for acromegaly is presented. The striking correspondence between the anatomy of the tumor and the geometry of the radiation ports is suggestive of a causal relationship. Previously reported cases of radiation-associated glioma are reviewed, and a brief appraisal of the evidence for induction of these lesions by radiation is presented. The differentiation of radiation-associated neoplasms from radionecrosis is also discussed.

  20. Adaptive Radiotherapy for an Uncommon Chloroma

    PubMed Central

    Majdoul, Soufya; Colson-Durand, Laurianne; To, Nu Hanh; Belkacemi, Yazid

    2016-01-01

    Granulocytic sarcomas, also referred to as chloromas or myeloid sarcomas, are extramedullary neoplasms that are composed of immature myeloid cells. This uncommon disease is known to be radiosensitive. However, the total dose and dose per fraction are not standardized. In addition, during the course of radiation therapy, significant reduction of the tumor is usually obtained. Thus, target volume reduction may require an intermediate radiotherapy plan evaluation for an adaptive treatment. A second plan at mid-dose is highly recommended. PMID:27920690

  1. Medical treatment for biochemical relapse after radiotherapy.

    PubMed

    Quero, L; Hennequin, C

    2014-10-01

    This article's purpose was to review the medical data justifying the use of a medical treatment for biochemical relapse after external beam radiotherapy. The MEDLINE database was searched to identify relevant information with the following medical subject headings: "prostate cancer", "radiotherapy" and "biochemical relapse". Prognostic factors affecting the overall survival of patients with a biochemical relapse after external beam radiotherapy have been identified: short prostate specific antigen (PSA)-doubling time (< 12 months), high PSA value (> 10 ng/mL) and short interval between treatment and biochemical relapse (< 18 months). If a second local treatment is not feasible, timing to initiate a salvage medical treatment is not defined. Particularly, randomized trials did not demonstrate a significant benefit of an early initiation of androgen deprivation treatment. Some retrospective studies suggest that an early androgen deprivation is justified if poor prognostic factors are found. However, if an androgen deprivation treatment is prescribed, intermittent schedule is non-inferior to a continuous administration and seems to offer a better quality of life. Many non-hormonal treatments have also been evaluated in this setting: only 5-alpha-reductase inhibitors could be proposed in some specific situations. In conclusion, the judicious use of a medical treatment for biochemical relapse is still debated. Given the natural history of this clinical situation, a simple surveillance is justified in many cases.

  2. [Influence of radiotherapy on lymphocyte stimulation].

    PubMed

    Renner, H; Renner, K H; Hassenstein, E

    1976-08-01

    More than 300 lymphocyte cultures of 12 patients with seminomas were examined during the prophylactic radiotherapy and, in several cases, during an extended period until 20.5 months after the end of the treatment. The object of this study was to find out by measuring the capacity of the lymphocytes to be stimulated in vitro wheather they could be damaged by the radiotherapy. Among other reasons, the above mentioned patients were chosen because they had been submitted to irradiations of vast volumes of lymphatic tissues at a uniform focal dose of 4000 rad. The different opinions expressed in the literature (stimulation decreassed resp. increased resp. unchanged) are reflected by our results in such a way that we did not find a qualitative loss of the capacity to be stimulated cultures. The problem of the different opinions about the capacity of lymphocytes to be stimulated after a radiotherapy appears; among other things, to be based on different examination methods. According to these methods- morphological determination of the relative number of lymphoblasts, synthesis of DNA by fluid scintillation counting, or determination of the number of surviving cells in vitro -different results are obtained. It seems not possible to use the lymphocyte stimulation in vitro as a method of testing clinical sideefects occuring during the characteristics of immunity and radiation biology are not differentiated in a more precise manner.

  3. Proton beam radiotherapy of iris melanoma

    SciTech Connect

    Damato, Bertil . E-mail: Bertil@damato.co.uk; Kacperek, Andrzej; Chopra, Mona; Sheen, Martin A.; Campbell, Ian R.; Errington, R. Douglas

    2005-09-01

    Purpose: To report on outcomes after proton beam radiotherapy of iris melanoma. Methods and Materials: Between 1993 and 2004, 88 patients with iris melanoma received proton beam radiotherapy, with 53.1 Gy in 4 fractions. Results: The patients had a mean age of 52 years and a median follow-up of 2.7 years. The tumors had a median diameter of 4.3 mm, involving more than 2 clock hours of iris in 32% of patients and more than 2 hours of angle in 27%. The ciliary body was involved in 20%. Cataract was present in 13 patients before treatment and subsequently developed in another 18. Cataract had a 4-year rate of 63% and by Cox analysis was related to age (p = 0.05), initial visual loss (p < 0.0001), iris involvement (p < 0.0001), and tumor thickness (p < 0.0001). Glaucoma was present before treatment in 13 patients and developed after treatment in another 3. Three eyes were enucleated, all because of recurrence, which had an actuarial 4-year rate of 3.3% (95% CI 0-8.0%). Conclusions: Proton beam radiotherapy of iris melanoma is well tolerated, the main problems being radiation-cataract, which was treatable, and preexisting glaucoma, which in several patients was difficult to control.

  4. Anal Cancer: An Examination of Radiotherapy Strategies

    SciTech Connect

    Glynne-Jones, Rob; Lim, Faye

    2011-04-01

    The Radiation Therapy Oncology Group 9811, ACCORD-03, and ACT II Phase III trials in anal cancer showed no benefit for cisplatin-based induction and maintenance chemotherapy, or radiation dose-escalation >59 Gy. This review examines the efficacy and toxicity of chemoradiation (CRT) in anal cancer, and discusses potential alternative radiotherapy strategies. The evidence for the review was compiled from randomized and nonrandomized trials of radiation therapy and CRT. A total of 103 retrospective/observational studies, 4 Phase I/II studies, 16 Phase II prospective studies, 2 randomized Phase II studies, and 6 Phase III trials of radiotherapy or chemoradiation were identified. There are no meta-analyses based on individual patient data. A 'one-size-fits-all' approach for all stages of anal cancer is inappropriate. Early T1 tumors are probably currently overtreated, whereas T3/T4 lesions might merit escalation of treatment. Intensity-modulated radiotherapy or the integration of biological therapy may play a role in future.

  5. Personalized radiotherapy: concepts, biomarkers and trial design

    PubMed Central

    Redalen, K R

    2015-01-01

    In the past decade, and pointing onwards to the immediate future, clinical radiotherapy has undergone considerable developments, essentially including technological advances to sculpt radiation delivery, the demonstration of the benefit of adding concomitant cytotoxic agents to radiotherapy for a range of tumour types and, intriguingly, the increasing integration of targeted therapeutics for biological optimization of radiation effects. Recent molecular and imaging insights into radiobiology will provide a unique opportunity for rational patient treatment, enabling the parallel design of next-generation trials that formally examine the therapeutic outcome of adding targeted drugs to radiation, together with the critically important assessment of radiation volume and dose-limiting treatment toxicities. In considering the use of systemic agents with presumed radiosensitizing activity, this may also include the identification of molecular, metabolic and imaging markers of treatment response and tolerability, and will need particular attention on patient eligibility. In addition to providing an overview of clinical biomarker studies relevant for personalized radiotherapy, this communication will highlight principles in addressing clinical evaluation of combined-modality-targeted therapeutics and radiation. The increasing number of translational studies that bridge large-scale omics sciences with quality-assured phenomics end points—given the imperative development of open-source data repositories to allow investigators the access to the complex data sets—will enable radiation oncology to continue to position itself with the highest level of evidence within existing clinical practice. PMID:25989697

  6. Personalized radiotherapy: concepts, biomarkers and trial design.

    PubMed

    Ree, A H; Redalen, K R

    2015-07-01

    In the past decade, and pointing onwards to the immediate future, clinical radiotherapy has undergone considerable developments, essentially including technological advances to sculpt radiation delivery, the demonstration of the benefit of adding concomitant cytotoxic agents to radiotherapy for a range of tumour types and, intriguingly, the increasing integration of targeted therapeutics for biological optimization of radiation effects. Recent molecular and imaging insights into radiobiology will provide a unique opportunity for rational patient treatment, enabling the parallel design of next-generation trials that formally examine the therapeutic outcome of adding targeted drugs to radiation, together with the critically important assessment of radiation volume and dose-limiting treatment toxicities. In considering the use of systemic agents with presumed radiosensitizing activity, this may also include the identification of molecular, metabolic and imaging markers of treatment response and tolerability, and will need particular attention on patient eligibility. In addition to providing an overview of clinical biomarker studies relevant for personalized radiotherapy, this communication will highlight principles in addressing clinical evaluation of combined-modality-targeted therapeutics and radiation. The increasing number of translational studies that bridge large-scale omics sciences with quality-assured phenomics end points-given the imperative development of open-source data repositories to allow investigators the access to the complex data sets-will enable radiation oncology to continue to position itself with the highest level of evidence within existing clinical practice.

  7. Single crystal diamond detector for radiotherapy

    NASA Astrophysics Data System (ADS)

    Schirru, F.; Kisielewicz, K.; Nowak, T.; Marczewska, B.

    2010-07-01

    The new generation of synthetic diamonds grown as a CVD single crystal on a high pressure high temperature substrate offers a wide range of applications. In particular, because of the near tissue equivalence and its small size (good spatial resolution), CVD single crystal diamond finds applicability in radiotherapy as a dosemeter of ionizing radiation. In this paper we report the electrical and dosimetric properties of a new diamond detector which was fabricated at IFJ based on a single crystal detector-grade CVD diamond provided with a novel contact metallization. Diamond properties were assessed at IFJ using a Theratron 680E therapeutic 60Co gamma rays unit and at COOK with 6 and 18 MV x-rays Varian Clinac CL2300 C/D accelerator. The new dosemeter showed high electric and dosimetric performances: low value of dark current, high current at the level of some nanoamperes during irradiation, very fast dynamic response with a rise time amounting to parts of a second, good stability and repeatability of the current and linearity of the detector signal at different dose and dose rate levels typically applied in radiotherapy. The results confirm the potential applicability of diamond material as a dosemeter for applications in radiotherapy.

  8. 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.

  9. Sacral plexus injury after radiotherapy for carcinoma of cervix

    SciTech Connect

    Stryker, J.A.; Sommerville, K.; Perez, R.; Velkley, D.E. )

    1990-10-01

    A 42-year-old woman developed lower extremity weakness and sensory loss 1 year after external and intracavitary radiotherapy for Stage IB carcinoma of cervix. She has been followed for 5 years posttreatment, and the neurologic abnormalities have persisted, but no evidence of recurrent carcinoma has been found. We believe this to be a rare case of sacral plexus radiculopathy developing as a late complication after radiotherapy. Suggestions are made for improving the radiotherapy technique to prevent this complication in future cases.

  10. MR Imaging Based Treatment Planning for Radiotherapy of Prostate Cancer

    DTIC Science & Technology

    2005-02-01

    treatment planning for radiotherapy : Dosimetric verification for prostate IiMRT" and " Dosimetric evaluation of MRI-based treatment planning for...Shawn M, Ma C-M, Freedman GM and Pollack A. MRI-Based Treatment Planning for Radiotherapy : Dosimetric Verification for Prostate IMRT. International...Freedman GM and Pollack A. MRI- Based Treatment Planning for Radiotherapy : Dosimetric Verification for Prostate ]IMRT. International Journal of Radiation

  11. 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.

  12. Biomarkers for DNA DSB inhibitors and radiotherapy clinical trials.

    PubMed

    Liu, Stanley K; Olive, Peggy L; Bristow, Robert G

    2008-09-01

    Major technical advances in radiotherapy, including IMRT and image-guided radiotherapy, have allowed for improved physical precision and increased dose delivery to the tumor, with better sparing of surrounding normal tissue. The development of inhibitors of the sensing and repair of DNA double-strand breaks (DSBs) is exciting and could be combined with precise radiotherapy targeting to improve local control following radiotherapy. However, caution must be exercised in order that DSB inhibitors are combined with radiotherapy in such a manner as to preserve the therapeutic ratio by exploiting repair deficiencies in malignant cells over that of normal cells. In this review, we discuss the rationale and current approaches to targeting DSB sensing and repair pathways in combined modality with radiotherapy. We also describe potential biomarkers that could be useful in detecting functional inhibition of DSB repair in a patient's tissues during clinical radiotherapy trials. Finally, we examine a number of issues relating to the use of DSB-inhibiting molecular agents and radiotherapy in the context of the tumor microenvironment, effects on normal tissues and the optimal timing and duration of the agent in relation to fractionated radiotherapy.

  13. Proton Radiotherapy for Liver Tumors: Dosimetric Advantages Over Photon Plans

    SciTech Connect

    Wang Xiaochun Krishnan, Sunil; Zhang Xiaodong; Dong Lei; Briere, Tina; Crane, Christopher H.; Martel, Mary; Gillin, Michael; Mohan, Radhe; Beddar, Sam

    2008-01-01

    The purpose of the study is to dosimetrically investigate the advantages of proton radiotherapy over photon radiotherapy for liver tumors. The proton plan and the photon plan were designed using commercial treatment planning systems. The treatment target dose conformity and heterogeneity and dose-volume analyses of normal structures were compared between proton and photon radiotherapy for 9 patients with liver tumors. Proton radiotherapy delivered a more conformal target dose with slightly less homogeneity when compared with photon radiotherapy. Protons significantly reduced the fractional volume of liver receiving dose greater or equal to 30 Gy (V{sub 30}) and the mean liver dose. The stomach and duodenal V{sub 45} were significantly lower with the use of proton radiotherapy. The V{sub 40} and V{sub 50} of the heart and the maximum spinal cord dose were also significantly lower with the use of proton radiotherapy. Protons were better able to spare one kidney completely and deliver less dose to one (generally the left) kidney than photons. The mean dose to the total body and most critical structures was significantly decreased using protons when compared to corresponding photon plans. In conclusion, our study suggests the dosimetric benefits of proton radiotherapy over photon radiotherapy. These dosimetric advantages of proton plans may permit further dose escalation with lower risk of complications.

  14. Dysphagia after radiotherapy: state of the art and prevention.

    PubMed

    Servagi-Vernat, S; Ali, D; Roubieu, C; Durdux, C; Laccourreye, O; Giraud, P

    2015-02-01

    Adjuvant radiotherapy after surgery or exclusive radiotherapy, with or without concurrent chemotherapy is a valuable treatment option in the great majority of patients with head and neck cancer. Recent technical progress in radiotherapy has resulted in a decreased incidence of xerostomia. Another common toxicity of radiotherapy is dysphagia, which alters the nutritional status and quality of life of patients in remission. The objective of this review is to describe the physiology of swallowing function, the pathophysiology of radiation-induced dysphagia and the various strategies currently available to prevent this complication.

  15. Radical hysterectomy with adjuvant radiotherapy versus radical radiotherapy for FIGO stage IIB cervical cancer

    PubMed Central

    2014-01-01

    Background The goal of this study was to compare treatment outcomes for Federation of Gynecology and Obstetrics (FIGO) stage IIB cervical carcinoma patients receiving radical surgery followed by adjuvant postoperative radiotherapy versus radical radiotherapy. Methods Medical records of FIGO stage IIB cervical cancer patients treated between July 2008 and December 2011 were retrospectively reviewed. A total of 148 patients underwent radical hysterectomy with pelvic lymph node dissection followed by adjuvant radiotherapy (surgery-based group). These patients were compared with 290 patients that received radical radiotherapy alone (RT-based group). Recurrence rates, progression-free survival (PFS), overall survival (OS), local control rates, and treatment-related complications were compared for these two groups. Results Similar rates of recurrence (16.89% vs. 12.41%, p = 0.200), PFS (log-rank, p = 0.211), OS (log-rank, p = 0.347), and local control rates (log-rank, p = 0.668) were observed for the surgery-based group and the RT-based group, respectively. Moreover, the incidence of acute grade 3–4 gastrointestinal reactions and late grade 3–4 lower limb lymphedema were significantly higher for the surgery-based group versus the RT-based group. Cox multivariate analyses found no significant difference in survival outcome between the two groups, and tumor diameter and histopathology were identified as significant prognostic factors for OS. Conclusions Radical radiotherapy was associated with fewer treatment-related complications and achieved comparable survival outcomes for patients with FIGO stage IIB cervical cancer compared to radical hysterectomy followed by postoperative radiotherapy. PMID:24495453

  16. Predictors of Long-Term Toxicity Using Three-Dimensional Conformal External Beam Radiotherapy to Deliver Accelerated Partial Breast Irradiation

    SciTech Connect

    Shaitelman, Simona F.; Kim, Leonard H.; Grills, Inga S.; Chen, Peter Y.; Ye Hong; Kestin, Larry L.; Yan Di; Vicini, Frank A.

    2011-11-01

    Purpose: We analyzed variables associated with long-term toxicity using three-dimensional conformal external beam radiation therapy (3D-CRT) to deliver accelerated partial breast irradiation. Methods and Materials: One hundred patients treated with 3D-CRT accelerated partial breast irradiation were evaluated using Common Terminology Criteria for Adverse Events version 4.0 scale. Cosmesis was scored using Harvard criteria. Multiple dosimetric and volumetric parameters were analyzed for their association with worst and last (W/L) toxicity outcomes. Results: Sixty-two patients had a minimum of 36 months of toxicity follow-up (median follow-up, 4.8 years). The W/L incidence of poor-fair cosmesis, any telangiectasia, and grade {>=}2 induration, volume reduction, and pain were 16.4%/11.5%, 24.2%/14.5%, 16.1%/9.7%, 17.7%/12.9%, and 11.3%/3.2%, respectively. Only the incidence of any telangiectasia was found to be predicted by any dosimetric parameter, with the absolute breast volume receiving 5% to 50% of the prescription dose (192.5 cGy-1925 cGy) being significant. No associations with maximum dose, volumes of lumpectomy cavity, breast, modified planning target volume, and PTV, dose homogeneity index, number of fields, and photon energy used were identified with any of the aforementioned toxicities. Non-upper outer quadrant location was associated with grade {>=}2 volume reduction (p = 0.02 W/p = 0.04 L). A small cavity-to-skin distance was associated with a grade {>=}2 induration (p = 0.03 W/p = 0.01 L), a borderline significant association with grade {>=}2 volume reduction (p = 0.06 W/p = 0.06 L) and poor-fair cosmesis (p = 0.08 W/p = 0.09 L), with threshold distances ranging from 5 to 8 mm. Conclusions: No dose--volume relationships associated with long-term toxicity were identified in this large patient cohort with extended follow-up. Cosmetic results were good-to-excellent in 88% of patients at 5 years.

  17. Effectiveness of Radiotherapy for Elderly Patients With Glioblastoma

    SciTech Connect

    Scott, Jacob; Tsai, Ya-Yu; Chinnaiyan, Prakash; Yu, Hsiang-Hsuan Michael

    2011-09-01

    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 analysis 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: Elderly

  18. A Four-Dimensional CT-Based Evaluation of Techniques for Gastric Irradiation

    SciTech Connect

    Geld, Ylanga G. van; Senan, Suresh; Soernsen de Koste, John R. van; Verbakel, Wilko F.A.R.; Slotman, Ben J.; Lagerwaard, Frank J.

    2007-11-01

    Purpose: To evaluate three-dimensional conformal (3D-CRT), intensity-modulated (IMRT) and respiration-gated radiotherapy (RGRT) techniques for gastric irradiation for target coverage and minimization of renal doses. All techniques were four-dimensional (4D)-CT based, incorporating the intrafractional mobility of the target volume and organs at risk (OAR). Methods and Materials: The stomach, duodenal C-loop, and OAR (kidneys, liver, and heart) were contoured in all 10 phases of planning 4D-CT scans for five patients who underwent abdominal radiotherapy. Planning target volumes (PTVs) encompassing all positions of the stomach (PTV{sub allphases}) were generated. Three respiratory phases for RGRT in inspiration and expiration were identified, and corresponding PTV{sub inspiration} and PTV{sub expiration} and OAR volumes were created. Landmark-based fields recommended for the Radiation Therapy Oncology Group (RTOG) 99-04 study protocol were simulated to assess PTV coverage. IMRT and 3D-CRT planning with and without additional RGRT planning were performed for all PTVs, and corresponding dose volume histograms were analyzed. Results: Use of landmark-based fields did not result in full geometric coverage of the PTV{sub allphases} in any patient. IMRT significantly reduced mean renal doses compared with 3D-CRT (15.0 Gy {+-} 0.9 Gy vs. 20.1 Gy {+-} 9.3 Gy and 16.6 Gy {+-} 1.5 Gy vs. 32.6 Gy {+-} 7.1 Gy for the left and right kidneys, respectively; p = 0.04). No significant increase in renal sparing was seen when adding RGRT to either 3D-CRT or IMRT. Tolerance doses to the other OAR were not exceeded. Conclusions: Individualized field margins are essential for gastric irradiation. IMRT plans significantly reduce renal doses, but the benefits of RGRT in gastric irradiation appear to be limited.

  19. 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

  20. Radiotherapy and breast reconstruction: oncology, cosmesis and complications

    PubMed Central

    Ashton, Mark W

    2012-01-01

    Breast reconstruction plays a highly important role in the management of patients with breast cancer, from a psycho-social and sexual stand-point. Given that immediate breast reconstruction does not impair the oncologic safety of breast cancer management, with no increase in local recurrence rates, and no delays in the initiation of adjuvant chemotherapy or radiotherapy, the need to balance cosmesis in reconstruction with the oncologic needs of breast cancer patients is no more evident than in the discussion of radiotherapy. Radiotherapy is essential adjuvant therapy in the treatment of breast cancer, with the use of adjuvant radiotherapy widely shown to reduce local recurrence after both partial and total mastectomy and shown to prolong both disease-free and overall survival in patients with nodal disease. In the setting of breast reconstruction, the effects of radiotherapy are potentially two-fold, with consideration required of the impact of breast reconstruction on the administration of and the initiation of radiotherapy, as well as the effects of radiotherapy on operative complications and cosmetic outcome following immediate breast reconstruction. The current editorial piece aims to analyze this balance, contrasting both autologous and implant-based reconstruction. The literature is still evolving as to the relative role of autologous vs. alloplastic reconstruction in the setting of radiotherapy, and the more recent introduction of acellular dermal matrix and other compounds further complicate the evidence. Fat grafting and evolving techniques in breast reconstruction will herald new discussions on this front. PMID:25083434

  1. 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

  2. Children Undergoing Radiotherapy: Swedish Parents' Experiences and Suggestions for Improvement.

    PubMed

    Ångström-Brännström, Charlotte; Engvall, Gunn; 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.

  3. Updates on clinical studies of selenium supplementation in radiotherapy.

    PubMed

    Puspitasari, Irma M; Abdulah, Rizky; Yamazaki, Chiho; Kameo, Satomi; Nakano, Takashi; Koyama, Hiroshi

    2014-05-29

    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.

  4. 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

  5. Our intraoperative boost radiotherapy experience and applications

    PubMed Central

    Günay, Semra; Alan, Ömür; Yalçın, Orhan; Türkmen, Aygen; Dizdar, Nihal

    2016-01-01

    Objective: To present our experience since November 2013, and case selection criteria for intraoperative boost radiotherapy (IObRT) that significantly reduces the local recurrence rate after breast conserving surgery in patients with breast cancer. Material and Methods: Patients who were suitable for IObRT were identified within the group of patients who were selected for breast conserving surgery at our breast council. A MOBETRON (mobile linear accelerator for IObRT) was used for IObRt during surgery. Results: Patients younger than 60 years old with <3 cm invasive ductal cancer in one focus (or two foci within 2 cm), with a histologic grade of 2–3, and a high possibility of local recurrence were admitted for IObRT application. Informed consent was obtained from all participants. Lumpectomy and sentinel lymph node biopsy was performed and advancement flaps were prepared according to the size and inclination of the conus following evaluation of tumor size and surgical margins by pathology. Distance to the thoracic wall was measured, and a radiation oncologist and radiation physicist calculated the required dose. Anesthesia was regulated with slower ventilation frequency, without causing hypoxia. The skin and incision edges were protected, the field was radiated (with 6 MeV electron beam of 10 Gy) and the incision was closed. In our cases, there were no major postoperative surgical or early radiotherapy related complications. Conclusion: The completion of another stage of local therapy with IObRT during surgery positively effects sequencing of other treatments like chemotherapy, hormonotherapy and radiotherapy, if required. IObRT increases disease free and overall survival, as well as quality of life in breast cancer patients. PMID:26985156

  6. Surgery Followed by Radiotherapy Versus Radiotherapy Alone for Metastatic Spinal Cord Compression From Unfavorable Tumors

    SciTech Connect

    Rades, Dirk; Huttenlocher, Stefan; Bajrovic, Amira; Karstens, Johann H.; Adamietz, Irenaeus A.; Kazic, Nadja; Rudat, Volker; Schild, Steven E.

    2011-12-01

    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 for 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.

  7. Basic immunology of antibody targeted radiotherapy

    SciTech Connect

    Wong, Jeffrey Y.C. . E-mail: jwong@coh.org

    2006-10-01

    Antibody targeted radiotherapy brings an important new treatment modality to Radiation oncology clinic. Radiation dose to tumor and normal tissues are determined by a complex interplay of antibody, antigen, tumor, radionuclide, and host-related factors. A basic understanding of these immunologic and physiologic factors is important to optimally utilize this therapy in the clinic. Preclinical and clinical studies need to be continued to broaden our understanding and to develop new strategies to further improve the efficacy of this promising form of targeted therapy.

  8. Characteristics of in vivo radiotherapy dosimetry.

    PubMed

    Edwards, C R; Mountford, P J

    2009-11-01

    The recent discussion and debate about the use of in vivo dosimetry as a routine component of the radiotherapy treatment process has not included the limitations introduced by the physical characteristics of the detectors. Although a robust calibration procedure will ensure acceptable uncertainties in the measurements of tumour dose, further work is required to confirm the accuracy of critical organ measurements with a diode or a thermoluminescent dosemeter outside the main field owing to limitations caused by a non-uniform X-ray energy response of the detector, differences between the X-ray energy spectrum inside and outside the main field, and contaminating electrons.

  9. [Quality and safety management for radiotherapy].

    PubMed

    Pourel, N; Meyrieux, C; Perrin, B

    2016-09-01

    Quality and safety management have been implemented for many years in healthcare structures (hospitals treating cancer, private radiotherapy centres). Their structure and formalization have improved progressively over time. These recommendations aim at describing the link between quality and safety management through its organization scheme based on quality-safety policy, process approach, document management and quality measurement. Dedicated tools, such as experience feedback, a priori risk mapping, to-do-lists and check-lists are shown as examples and recommended as routine practice.

  10. State of the art of radiotherapy.

    PubMed

    Garrido, Pilar; Olmedo, Eugenia

    2013-06-01

    Locally advanced or stage III disease accounts for ~30% of patients with non-small-cell lung cancer (NSCLC), which means only in the United States, more than 50,000 new patients each year. Stage III is a very heterogeneous disease, the management of patients is complex and several conditions (performance status, weight loss, comorbidities, characteristics of nodal involvement or resectability) must be considered before selecting the best treatment, which in most cases is chemotherapy (CT) and radiotherapy (RT). In this article, we will review key changes in the management of unresectable stage III during the last decades. Also we will highlight some challenges and areas of active research.

  11. Ichthyosiform scaling secondary to megavoltage radiotherapy

    SciTech Connect

    Ross, E.V. )

    1991-07-01

    Acquired ichthyosis is a rare dermatosis associated with a number of malignancies. Side effects seen on the skin secondary to megavoltage radiotherapy are uncommon but may include fine dry desquamation and tanning. The authors present a case of ichthyosiform scaling limited to the radiation fields in a patient treated for brain metastases of a primary small cell lung carcinoma. The reader is reminded that side effects of megavoltage treatment do occur on the skin. A brief review of these effects is included. 5 references.

  12. Radiotherapy changes of the pediatric hip

    SciTech Connect

    Libshitz, H.I.; Edeiken, B.S.

    1981-09-01

    Significant radiation-induced abnormalities (aseptic necrosis of the femoral heads, slipped capital femoral epiphysis, radiation-induced sarcoma) were identified in eight of 44 patients aged 16 years or younger at the time of radiotherapy and followed for at least 3 years. The incidence is 18% in the entire group and 25% (8/32) if only patients with radiographs of the hips 3 or more years after therapy are considered. The first evidence of abnormality developed 13 years after irradiation in one patient. The need for long term follow-up of therapeutically irradiated children is stressed.

  13. Particle radiotherapy with carbon ion beams

    PubMed Central

    2013-01-01

    Carbon ion radiotherapy offers superior dose conformity in the treatment of deep-seated malignant tumours compared with conventional X-ray therapy. In addition, carbon ion beams have a higher relative biological effectiveness compared with protons or X-ray beams. The algorithm of treatment planning and beam delivery system is tailored to the individual parameters of the patient. The present article reviews the available literatures for various disease sites including the head and neck, skull base, lung, liver, prostate, bone and soft tissues and pelvic recurrence of rectal cancer as well as physical and biological properties. PMID:23497542

  14. Variations in energy spectra and water-to-material stopping-power ratios in three-dimensional conformal and intensity-modulated photon fields

    SciTech Connect

    Jang, Si Young; Liu, H. Helen; Mohan, Radhe; Siebers, Jeffrey V.

    2007-04-15

    Because of complex dose distributions and dose gradients that are created in three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT), photon- and electron-energy spectra might change significantly with spatial locations and doses. This study examined variations in photon- and electron-energy spectra in 3D-CRT and IMRT photon fields. The effects of spectral variations on water-to-material stopping-power ratios used in Monte Carlo treatment planning systems and the responses of energy-dependent dosimeters, such as thermoluminescent dosimeters (TLDs) and radiographic films were further studied. The EGSnrc Monte Carlo code was used to simulate megavoltage 3D-CRT and IMRT photon fields. The photon- and electron-energy spectra were calculated in 3D water phantoms and anthropomorphic phantoms based on the fluence scored in voxel grids. We then obtained the water-to-material stopping-power ratios in the local voxels using the Spencer-Attix cavity theory. Changes in the responses of films and TLDs were estimated based on the calculated local energy spectra and published data on the dosimeter energy dependency. Results showed that the photon-energy spectra strongly depended on spatial positions and doses in both the 3D-CRT and IMRT fields. The relative fraction of low-energy photons (<100 keV) increased inversely with the photon dose in low-dose regions of the fields. A similar but smaller effect was observed for electrons in the phantoms. The maximum variation of the water-to-material stopping-power ratio over the range of calculated dose for both 3D-CRT and IMRT was negligible (<1.0%) for ICRU tissue, cortical bone, and soft bone and less than 3.6% for dry air and lung. Because of spectral softening at low doses, radiographic films in the phantoms could over-respond to dose by more than 30%, whereas the over-response of TLDs was less than 10%. Thus, spatial variations of the photon- and electron-energy spectra should be considered

  15. 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.

  16. 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.

  17. Fractionated radiotherapy and radiosurgery of intracranial meningiomas.

    PubMed

    Biau, J; Khalil, T; Verrelle, P; Lemaire, J-J

    2015-06-19

    This review focuses on the role of radiosurgery and fractionated radiotherapy in the management of intracranial meningiomas, which are the most common benign intracranial tumors. Whenever feasible, surgery remains a cornerstone of treatment in effective health care treatment where modern radiotherapy plays an important role. Irradiation can be proposed as first-line treatment, as adjuvant treatment, or as a second-line treatment after recurrence. Stereotactic radiosurgery consists of delivering, a high-dose of radiation with high precision, to the tumor in a single-fraction with a minimal exposure of surrounding healthy tissue. Stereotactic radiosurgery, especially with the gamma knife technique, has reached a high level of success for the treatment of intracranial meningiomas with excellent local control and low morbidity. However, stereotactic radiosurgery is limited by tumor size,<3-4cm, and location, i.e. reasonable distance from the organs at risk. Fractionated radiation therapy is an interesting alternative (5 to 6weeks treatment time) for large inoperable tumors. The results of fractionated radiation therapy seem encouraging as regards both local control and morbidity although long-term prospective studies are still needed.

  18. Cataractogenesis after Cobalt-60 eye plaque radiotherapy

    SciTech Connect

    Kleineidam, M.; Augsburger, J.J. ); Hernandez, C.; Glennon, P.; Brady, L.W. )

    1993-07-15

    This study was designed to estimate the actuarial incidence of typical postirradiation cataracts and to identify prognostic factors related to their development in melanoma-containing eyes treated by Cobalt-60 plaque radiotherapy. A special interest was the impact of calculated radiation dose and dose-rate to the lens. The authors evaluated the actuarial occurrence of post-irradiation cataract in 365 patients with primary posterior uveal melanoma treated by Cobalt-60 plaque radiotherapy between 1976 and 1986. Only 22% (S.E. = 4.6%) of the patients who received a total dose of 6 to 20 Gy at the center of the lens developed a visually significant cataract attributable to the radiation within 5 years after treatment. Using multivariate Cox proportional hazards modeling, the authors identified thickness of the tumor, location of the tumor's anterior margin relative to the equatorward and the ora serrata, and diameter of the eye plaque used as the best combination of covariables for predicting length of time until development of cataract. Surprisingly, the dose of radiation delivered to the lens, which was strongly correlated to all of these covariables, was not a significant predictive factor in multivariate analysis. The results suggest that success of efforts to decrease the occurrence rate of post-irradiation cataracts by better treatment planning might be limited in patients with posterior uveal melanoma. 21 refs., 2 figs., 5 tabs.

  19. Dose masking feature for BNCT radiotherapy planning

    DOEpatents

    Cook, Jeremy L.; Wessol, Daniel E.; Wheeler, Floyd J.

    2000-01-01

    A system for displaying an accurate model of isodoses to be used in radiotherapy so that appropriate planning can be performed prior to actual treatment on a patient. The nature of the simulation of the radiotherapy planning for BNCT and Fast Neutron Therapy, etc., requires that the doses be computed in the entire volume. The "entire volume" includes the patient and beam geometries as well as the air spaces in between. Isodoses derived from the computed doses will therefore extend into the air regions between the patient and beam geometries and thus depict the unrealistic possibility that radiation deposition occurs in regions containing no physical media. This problem is solved by computing the doses for the entire geometry and then masking the physical and air regions along with the isodose contours superimposed over the patient image at the corresponding plane. The user is thus able to mask out (remove) the contour lines from the unwanted areas of the image by selecting the appropriate contour masking region from the raster image.

  20. In vivo dosimetry in external beam radiotherapy

    SciTech Connect

    Mijnheer, Ben; Beddar, Sam; Izewska, Joanna; Reft, Chester

    2013-07-15

    In vivo dosimetry (IVD) is in use in external beam radiotherapy (EBRT) to detect major errors, to assess clinically relevant differences between planned and delivered dose, to record dose received by individual patients, and to fulfill legal requirements. After discussing briefly the main characteristics of the most commonly applied IVD systems, the clinical experience of IVD during EBRT will be summarized. Advancement of the traditional aspects of in vivo dosimetry as well as the development of currently available and newly emerging noninterventional technologies are required for large-scale implementation of IVD in EBRT. These new technologies include the development of electronic portal imaging devices for 2D and 3D patient dosimetry during advanced treatment techniques, such as IMRT and VMAT, and the use of IVD in proton and ion radiotherapy by measuring the decay of radiation-induced radionuclides. In the final analysis, we will show in this Vision 20/20 paper that in addition to regulatory compliance and reimbursement issues, the rationale for in vivo measurements is to provide an accurate and independent verification of the overall treatment procedure. It will enable the identification of potential errors in dose calculation, data transfer, dose delivery, patient setup, and changes in patient anatomy. It is the authors' opinion that all treatments with curative intent should be verified through in vivo dose measurements in combination with pretreatment checks.

  1. [Antalgic radiotherapy in lumbosacral carcinomatous neuropathies].

    PubMed

    Russi, E G; Gaeta, M; Pergolizzi, S; Settineri, N; Frosina, P; De Renzis, C

    1994-06-01

    Lumbosacral carcinomatous neuropathy (LCN) may be caused by infiltration or compression of the lumbosacral plexi and nerves from intrapelvic or paraaortic neoplasms. The authors submitted 23 patients complaining of LCN with CT documented intrapelvic or paraaortic tumors to palliative radiotherapy. Megavoltage external beam irradiation was administered using a 6-MV linear accelerator. Treatment field sizes ranged from 56 cm2 to 235 cm2 (mean: 150.54 cm2) and encompassed only the site where the disease involved the lumbosacral plexus or its branches. > or = 3 Gy/day fractions were used. Twenty-one of 22 assessable patients (95.4%) obtained LCN pain relief; 19 (86.3%) obtained complete LCN pain relief. The median time to pain progression (TPP) was 150 days (range: 39-510 days). The median survival was 165 days. Seven patients were LCN pain-free at death. Two patients are alive and LCN pain-free. The remaining 12 patients had recurrent LCN pain: four of them were reirradiated at the site of previous neuropathy and only two had partial relief again. The authors conclude that it is advisable to submit to palliative radiotherapy the inoperable disseminated and/or recurrent cancer patients complaining of LCN, to use large fractions not to occupy the extant time of their already short life-expectancy, and to design small fields to avoid acute side-effects.

  2. Cerebral aneurysms following radiotherapy for medulloblastoma

    SciTech Connect

    Benson, P.J.; Sung, J.H.

    1989-04-01

    Three patients, two males and one female aged 21, 14, and 31 years, respectively, developed cerebral saccular aneurysms several years after undergoing radiotherapy for cerebellar medulloblastoma at 2, 5, and 14 years of age, respectively. Following surgery, all three received combined cobalt-60 irradiation and intrathecal colloidal radioactive gold (/sup 198/Au) therapy, and died from rupture of the aneurysm 19, 9, and 17 years after the radiotherapy, respectively. Autopsy examination revealed no recurrence of the medulloblastoma, but widespread radiation-induced vasculopathy was found at the base of the brain and in the spinal cord, and saccular aneurysms arose from the posterior cerebral arteries at the basal cistern or choroidal fissure. The aneurysms differed from the ordinary saccular aneurysms of congenital type in their location and histological features. Their locations corresponded to the areas where intrathecally administered colloidal /sup 198/Au is likely to pool, and they originated directly from a segment of the artery rather than from a branching site as in congenital saccular aneurysms. It is, therefore, concluded that the aneurysms in these three patients were most likely radiation-induced.

  3. Liver-Directed Radiotherapy for Hepatocellular Carcinoma

    PubMed Central

    Keane, Florence K.; Wo, Jennifer Y.; Zhu, Andrew X.; Hong, Theodore S.

    2016-01-01

    Background The incidence of hepatocellular carcinoma (HCC) continues to increase world-wide. Many patients present with advanced disease with extensive local tumor or vascular invasion and are not candidates for traditionally curative therapies such as orthotopic liver transplantation (OLT) or resection. Radiotherapy (RT) was historically limited by its inability to deliver a tumoricidal dose; however, modern RT techniques have prompted renewed interest in the use of liver-directed RT to treat patients with primary hepatic malignancies. Summary The aim of this review was to discuss the use of external beam RT in the treatment of HCC, with particular focus on the use of stereotactic body radiotherapy (SBRT). We review the intricacies of SBRT treatment planning and delivery. Liver-directed RT involves accurate target identification, precise and reproducible patient immobilization, and assessment of target and organ motion. We also summarize the published data on liver-directed RT, and demonstrate that it is associated with excellent local control and survival rates, particularly in patients who are not candidates for OLT or resection. Key Messages Modern liver-directed RT is safe and effective for the treatment of HCC, particularly in patients who are not candidates for OLT or resection. Liver-directed RT, including SBRT, depends on accurate target identification, precise and reproducible patient immobilization, and assessment of target and organ motion. Further prospective studies are needed to fully delineate the role of liver-directed RT in the treatment of HCC. PMID:27493895

  4. Radiotherapy dosimetry using a commercial OSL system

    SciTech Connect

    Viamonte, A.; Rosa, L. A. R. da; Buckley, L. A.; Cherpak, A.; Cygler, J. E.

    2008-04-15

    A commercial optically stimulated luminescence (OSL) system developed for radiation protection dosimetry by Landauer, Inc., the InLight microStar reader, was tested for dosimetry procedures in radiotherapy. The system uses carbon-doped aluminum oxide, Al{sub 2}O{sub 3}:C, as a radiation detector material. Using this OSL system, a percent depth dose curve for {sup 60}Co gamma radiation was measured in solid water. Field size and SSD dependences of the detector response were also evaluated. The dose response relationship was investigated between 25 and 400 cGy. The decay of the response with time following irradiation and the energy dependence of the Al{sub 2}O{sub 3}:C OSL detectors were also measured. The results obtained using OSL dosimeters show good agreement with ionization chamber and diode measurements carried out under the same conditions. Reproducibility studies show that the response of the OSL system to repeated exposures is 2.5% (1sd), indicating a real possibility of applying the Landauer OSL commercial system for radiotherapy dosimetric procedures.

  5. Monte Carlo dose calculations in advanced radiotherapy

    NASA Astrophysics Data System (ADS)

    Bush, Karl Kenneth

    The remarkable accuracy of Monte Carlo (MC) dose calculation algorithms has led to the widely accepted view that these methods should and will play a central role in the radiotherapy treatment verification and planning of the future. The advantages of using MC clinically are particularly evident for radiation fields passing through inhomogeneities, such as lung and air cavities, and for small fields, including those used in today's advanced intensity modulated radiotherapy techniques. Many investigators have reported significant dosimetric differences between MC and conventional dose calculations in such complex situations, and have demonstrated experimentally the unmatched ability of MC calculations in modeling charged particle disequilibrium. The advantages of using MC dose calculations do come at a cost. The nature of MC dose calculations require a highly detailed, in-depth representation of the physical system (accelerator head geometry/composition, anatomical patient geometry/composition and particle interaction physics) to allow accurate modeling of external beam radiation therapy treatments. To perform such simulations is computationally demanding and has only recently become feasible within mainstream radiotherapy practices. In addition, the output of the accelerator head simulation can be highly sensitive to inaccuracies within a model that may not be known with sufficient detail. The goal of this dissertation is to both improve and advance the implementation of MC dose calculations in modern external beam radiotherapy. To begin, a novel method is proposed to fine-tune the output of an accelerator model to better represent the measured output. In this method an intensity distribution of the electron beam incident on the model is inferred by employing a simulated annealing algorithm. The method allows an investigation of arbitrary electron beam intensity distributions and is not restricted to the commonly assumed Gaussian intensity. In a second component of

  6. Uses of megavoltage digital tomosynthesis in radiotherapy

    NASA Astrophysics Data System (ADS)

    Sarkar, Vikren

    With the advent of intensity modulated radiotherapy, radiation treatment plans are becoming more conformal to the tumor with the decreasing margins. It is therefore of prime importance that the patient be positioned correctly prior to treatment. Therefore, image guided treatment is necessary for intensity modulated radiotherapy plans to be implemented successfully. Current advanced imaging devices require costly hardware and software upgrade, and radiation imaging solutions, such as cone beam computed tomography, may introduce extra radiation dose to the patient in order to acquire better quality images. Thus, there is a need to extend current existing imaging device ability and functions while reducing cost and radiation dose. Existing electronic portal imaging devices can be used to generate computed tomography-like tomograms through projection images acquired over a small angle using the technique of cone-beam digital tomosynthesis. Since it uses a fraction of the images required for computed tomography reconstruction, use of this technique correspondingly delivers only a fraction of the imaging dose to the patient. Furthermore, cone-beam digital tomosynthesis can be offered as a software-only solution as long as a portal imaging device is available. In this study, the feasibility of performing digital tomosynthesis using individually-acquired megavoltage images from a charge coupled device-based electronic portal imaging device was investigated. Three digital tomosynthesis reconstruction algorithms, the shift-and-add, filtered back-projection, and simultaneous algebraic reconstruction technique, were compared considering the final image quality and radiation dose during imaging. A software platform, DART, was created using a combination of the Matlab and C++ languages. The platform allows for the registration of a reference Cone Beam Digital Tomosynthesis (CBDT) image against a daily acquired set to determine how to shift the patient prior to treatment. Finally

  7. [Intensity modulated radiotherapy for head and neck cancer, dose constraint for normal tissue: Cochlea vestibular apparatus and brainstem].

    PubMed

    Guimas, V; Thariat, J; Graff-Cailleau, P; Boisselier, P; Pointreau, Y; Pommier, P; Montbarbon, X; Laude, C; Racadot, S

    2016-10-01

    Modern techniques such as intensity modulated radiation therapy (IMRT) have been proven to significantly decrease the dose delivered to the cochleovestibular apparatus, limiting consecutive toxicity especially for sensorineural hearing loss. However, recent data still report a 42% rate of radio-induced hypoacusia underscoring the need to protect the cochleovestibular apparatus. Due to the small size of the cochlea, a precise dose-volume analysis could not be performed, and recommendations only refer to the mean dose. Confusing factors such as age, concomitant chemotherapy, primary site and tumor stage should be taken into account at the time of treatment planning. (Non-coplanar) VMAT and tomotherapy have been proven better at sparing the cochlea in comparison with 3D CRT. Brainstem radio-induced injuries were poorly studied because of their infrequency and the difficulty of distinguishing between necrosis and tumor progression in the case of a primary tumor located at the base of skull. The following toxicities have been described: brainstem focal radionecrosis, cognitive disorders without dementia, cranial nerve injuries and sensori motor disability. Maximal dose to the brainstem should be kept to < 54Gy for conventional fractionation. This dose could be exceeded (no more than 10mL should receive more than 59Gy), provided this hot spot is located in the peripheral area of the organ.

  8. TU-F-BRE-07: In Vivo Neutron Detection in Patients Undergoing Stereotactic Ablative Radiotherapy (SABR) for Primary Kidney Cancer Using 6Li and 7Li Enriched TLD Pairs

    SciTech Connect

    Lonski, P; Kron, T; Franich, R; Keehan, S; Siva, S; Taylor, M

    2014-06-15

    Purpose: Stereotactic ablative radiotherapy (SABR) for primary kidney cancer often involves the use of high-energy photons combined with a large number of monitor units. While important for risk assessment, the additional neutron dose to untargeted healthy tissue is not accounted for in treatment planning. This work aims to detect out-of-field neutrons in vivo for patients undergoing SABR with high-energy (>10 MV) photons and provides preliminary estimates of neutron effective dose. Methods: 3 variations of high-sensitivity LiF:Mg,Cu,P thermoluminescent dosimeter (TLD) material, each with varying {sup 6}Li / {sup 7}Li concentrations, were used in custom-made Perspex holders for in vivo measurements. The variation in cross section for thermal neutrons between Li isotopes was exploited to distinguish neutron from photon signal. Measurements were made out-of-field for 7 patients, each undergoing 3D-conformal SABR treatment for primary kidney cancer on a Varian 21iX linear accelerator. Results: In vivo measurements show increased signal for the {sup 6}Li enriched material for patients treated with 18 MV photons. Measurements on one SABR patient treated using only 6 MV showed no difference between the 3 TLD materials. The out-of-field photon signal decreased exponentially with distance from the treatment field. The neutron signal, taken as the difference between {sup 6}Li enriched and {sup 7}Li enriched TLD response, remains almost constant up to 50 cm from the beam central axis. Estimates of neutron effective dose from preliminary TLD calibration suggest between 10 and 30 mSv per 1000 MU delivered at 18 MV for the 7 patients. Conclusion: TLD was proven to be a useful tool for the purpose of in vivo neutron detection at out-of-field locations. Further work is required to understand the relationship between TL signal and neutron dose. Dose estimates based on preliminary TLD calibration in a neutron beam suggest the additional neutron dose was <30 mSv per 1000 MU at 18 MV.

  9. Laryngeal sensation and pharyngeal delay time after (chemo)radiotherapy.

    PubMed

    Maruo, Takashi; Fujimoto, Yasushi; Ozawa, Kikuko; Hiramatsu, Mariko; Suzuki, Atsushi; Nishio, Naoki; Nakashima, Tsutomu

    2014-08-01

    The objective of the study was to evaluate the association between changes in laryngeal sensation and initiation of swallowing reflex or swallowing function before and after (chemo)radiotherapy. A prospective study was conducted in a tertiary referral university hospital. Thirteen patients who received (chemo)radiotherapy for treatment of laryngeal or hypopharyngeal cancer were included. Laryngeal sensation was evaluated at the tip of the epiglottis before and 1, 3 months, and 1 year after (chemo)radiotherapy. Videofluoroscopy was performed at the same time. Quantitative determinations included changes in laryngeal sensation, computed analysis of pharyngeal delay time, the distance and velocity of hyoid bone movement during the phase of hyoid excursion, and pharyngeal residue rate (the proportion of the bolus that was left as residue in the pharynx at the first swallow). Laryngeal sensation significantly deteriorated 1 month after (chemo)radiotherapy, but there was a tendency to return to pretreatment levels 1 year after treatment. Neither pharyngeal delay time nor displacement of the hyoid bone changed significantly before and after (chemo)radiotherapy. In addition, there was no significant difference in the mean velocity of hyoid bone movement and the amount of stasis in the pharynx at the first swallow before and after (chemo)radiotherapy. After (chemo)radiotherapy, laryngeal sensation deteriorated. But, in this study, videofluoroscopy showed that swallowing reflex and function were maintained.

  10. Radiotherapy enhances laser palliation of malignant dysphagia: a randomised study.

    PubMed Central

    Sargeant, I R; Tobias, J S; Blackman, G; Thorpe, S; Glover, J R; Bown, S G

    1997-01-01

    BACKGROUND/AIMS: A major drawback of laser endoscopy in the palliation of malignant dysphagia is the need for repeated treatments. This study was designed to test whether external beam radiotherapy would reduce the necessity for repeated laser therapy. PATIENTS/METHODS: Sixty seven patients with inoperable oesophageal or gastric cardia cancers and satisfactory swallowing after initial laser recanalisation were randomised to palliative external beam radiotherapy (30 Gy in 10 fractions) or no radiotherapy. All patients underwent a 'check' endoscopy five weeks after initial recanalisation and were subsequently reendoscoped only for recurrent dysphagia, which occurred in 59 patients. RESULTS: Dysphagia was relieved equally well in both groups and the improvement was maintained with further endoscopic treatment. The initial dysphagia controlled interval and the duration between procedures required to maintain lifelong palliation (treatment interval) increased from five to nine weeks (median) in the radiotherapy group (p < 0.01 both parameters). Radiotherapy was well tolerated in all but three patients. One perforation occurred and two fistulae opened after dilatation in patients who received radiotherapy. CONCLUSION: Additional radiotherapy reduces the necessity for therapeutic endoscopy for a patient's remaining life. It has an important role in relatively well patients who are likely to survive long enough to benefit. PMID:9135526

  11. Cerebral necrosis after 25Gy radiotherapy in childhood followed 28 years later by 54Gy radiotherapy.

    PubMed

    Koot, Radboud W; Stalpers, Lukas J A; Aronica, Eleonora; Andries Bosch, D

    2007-09-01

    The development of brain necrosis is life-long risk of repeat radiation therapy, even after a long time interval and a moderate radiation dose. We report on a 34-year-old patient who had prophylactic cranial irradiation with 25Gy and adjuvant chemotherapy in childhood for leukaemia and in adulthood, 28 years later, therapeutic radiotherapy with 54Gy for an atypical (WHO grade II) meningioma. About 2 years later he developed a contrast-enhancing lesion on MRI-scan that was indicative of a tumor according to a thallium-201 ((201)Tl) SPECT scan. Histopathology of the operated contrast-enhancing lesion showed extensive radionecrosis. Radiation necrosis is a small but serious risk after repeat radiation therapy, even after a very long-term interval, the delivery of small fractions and an average cumulative total dose. Patients undergoing repeat radiotherapy therefore need to be followed life-long for potential late radiation toxicity.

  12. Long-Term Breast Cancer Patient Outcomes After Adjuvant Radiotherapy Using Intensity-Modulated Radiotherapy or Conventional Tangential Radiotherapy.

    PubMed

    Yang, Jen-Fu; Lee, Meei-Shyuan; Lin, Chun-Shu; Chao, Hsing-Lung; Chen, Chang-Ming; Lo, Cheng-Hsiang; Fan, Chao-Yueh; Tsao, Chih-Cheng; Huang, Wen-Yen

    2016-03-01

    The aim of the article is to analyze breast cancer patient clinical outcomes after long-term follow-up using intensity-modulated radiotherapy (IMRT) or conventional tangential radiotherapy (cRT). We retrospectively reviewed patients with stage 0-III breast cancer who received breast conserving therapy between April 2004 and December 2007. Of the 234 patients, 103 (44%) were treated with IMRT and 131 (56%) were treated with cRT. A total prescription dose of 45 to 50 Gy (1.8-2 Gy per fraction) was delivered to the whole breast. A 14 Gy boost dose was delivered in 7 fractions. The median follow-up was 8.2 years. Five of 131 (3.8%) cRT-treated patients and 2 of 103 (1.9%) IMRT-treated patients had loco-regional failure. The 8-year loco-regional failure-free survival rates were 96.7% and 97.6% (P = 0.393) in the cRT and IMRT groups, respectively, whereas the 8-year disease-free survival (DFS) rates were 91.2% and 93.1%, respectively (P = 0.243). Patients treated with IMRT developed ≥ grade 2 acute dermatitis less frequently than patients treated with cRT (40.8% vs 56.5%; P = 0.017). There were no differences in late toxicity. IMRT reduces ≥ grade 2 acute skin toxicity. Local control, DFS, and overall survival were equivalent with IMRT and cRT. IMRT can be considered a standard technique for breast cancer treatment.

  13. Brain necrosis after radiotherapy for primary intracerebral tumor.

    PubMed

    Hohwieler, M L; Lo, T C; Silverman, M L; Freidberg, S R

    1986-01-01

    Radiotherapy is a standard postoperative treatment for cerebral glioma. We have observed the onset of symptoms related to brain necrosis, as opposed to recurrent tumor, in surviving patients. This has been manifest as dementia with a computed tomographic pattern of low density in the frontal lobe uninvolved with tumor, but within the field of radiotherapy. Two patients presented with mass lesions also unrelated to recurrent tumor. We question the necessity of full brain irradiation and suggest that radiotherapy techniques be altered to target the tumor and not encompass the entire brain.

  14. Synergistic Effects of Gold Nanocages in Hyperthermia and Radiotherapy Treatment

    NASA Astrophysics Data System (ADS)

    Zhang, Ai-wei; Guo, Wei-hua; Qi, Ya-fei; Wang, Jian-zhen; Ma, Xiang-xing; Yu, De-xin

    2016-06-01

    Gold nanocages (GNCs) are a promising material that not only converts near infrared (NIR) light to heat for the ablation of tumors but also acts as a radiosensitizer. The combination of hyperthermia and radiotherapy has a synergistic effect that can lead to significant tumor cell necrosis. In the current study, we synthesized GNCs that offered the combined effects of hyperthermia and radiotherapy. This combination strategy resulted in increased tumor cell apoptosis and significant tumor tissue necrosis. We propose that GNCs can be used for clinical treatment and to potentially overcome resistance to radiotherapy by clearly increasing the antitumor effect.

  15. [Endocrine function following cranial radiotherapy of neoplasms in children].

    PubMed

    Couselo Sánchez, J M; Fernández Bujía, M L; Pombo Arias, M; Devesa Múgiga, J; Tojo Sierra, R; Peña Guitán, J

    1984-01-01

    The effect of radiotherapy upon the diencephalo-hypophyseal axis was studied in 14 children that had received cranial radio-therapy (2,400 to 6,000 R) to treat different intracranial tumors. Several hormones were evaluated between 2 months and 3 years after radiotherapy was performed. 35.7 per 100 of the patients were deficient in growth hormone, 37.5 per 100 showed an alteration of prolactin secretion, and 28 per 100 an abnormal response to thyroid-stimulating hormone.

  16. Intensity-Modulated Radiotherapy for Sinonasal Cancer: Improved Outcome Compared to Conventional Radiotherapy

    SciTech Connect

    Dirix, Piet; Vanstraelen, Bianca; Jorissen, Mark; Vander Poorten, Vincent; Nuyts, Sandra

    2010-11-15

    Purpose: To evaluate clinical outcome and toxicity of postoperative intensity-modulated radiotherapy (IMRT) for malignancies of the nasal cavity and paranasal sinuses. Methods and Materials: Between 2003 and 2008, 40 patients with cancer of the paranasal sinuses (n = 34) or nasal cavity (n = 6) received postoperative IMRT to a dose of 60 Gy (n = 21) or 66 Gy (n = 19). Treatment outcome and toxicity were retrospectively compared with that of a previous patient group (n = 41) who were also postoperatively treated to the same doses but with three-dimensional conformal radiotherapy without intensity modulation, from 1992 to 2002. Results: Median follow-up was 30 months (range, 4-74 months). Two-year local control, overall survival, and disease-free survival were 76%, 89%, and 72%, respectively. Compared to the three-dimensional conformal radiotherapy treatment, IMRT resulted in significantly improved disease-free survival (60% vs. 72%; p = 0.02). No grade 3 or 4 toxicity was reported in the IMRT group, either acute or chronic. The use of IMRT significantly reduced the incidence of acute as well as late side effects, especially regarding skin toxicity, mucositis, xerostomia, and dry-eye syndrome. Conclusions: Postoperative IMRT for sinonasal cancer significantly improves disease-free survival and reduces acute as well as late toxicity. Consequently, IMRT should be considered the standard treatment modality for malignancies of the nasal cavity and paranasal sinuses.

  17. High-LET charged particle radiotherapy

    SciTech Connect

    Castro, J.R. |

    1991-07-01

    The Department of Radiation Oncology at UCSF Medical Center and the Radiation Oncology Department at UC Lawrence Berkeley Laboratory have been evaluating the use of high LET charged particle radiotherapy in a Phase 1--2 research trial ongoing since 1979. In this clinical trail, 239 patients have received at least 10 Gy (physical) minimum tumor dose with neon ions, meaning that at least one-half of their total treatment was given with high-LET charged particle therapy. Ninety-one patients received all of their therapy with neon ions. Of the 239 patients irradiated, target sites included lesions in the skin, subcutaneous tissues, head and neck such as paranasal sinuses, nasopharynx and salivary glands (major and minor), skull base and juxtaspinal area, GI tract including esophagus, pancreas and biliary tract, prostate, lung, soft tissue and bone. Analysis of these patients has been carried out with a minimum followup period of 2 years.

  18. [Radiotherapy phase I trials' methodology: Features].

    PubMed

    Rivoirard, R; Vallard, A; Langrand-Escure, J; Guy, J-B; Ben Mrad, M; Yaoxiong, X; Diao, P; Méry, B; Pigne, G; Rancoule, C; Magné, N

    2016-12-01

    In clinical research, biostatistical methods allow the rigorous analysis of data collection and should be defined from the trial design to obtain the appropriate experimental approach. Thus, if the main purpose of phase I is to determine the dose to use during phase II, methodology should be finely adjusted to experimental treatment(s). Today, the methodology for chemotherapy and targeted therapy is well known. For radiotherapy and chemoradiotherapy phase I trials, the primary endpoint must reflect both effectiveness and potential treatment toxicities. Methodology should probably be complex to limit failures in the following phases. However, there are very few data about methodology design in the literature. The present study focuses on these particular trials and their characteristics. It should help to raise existing methodological patterns shortcomings in order to propose new and better-suited designs.

  19. TOPICAL REVIEW: Anatomical imaging for radiotherapy

    NASA Astrophysics Data System (ADS)

    Evans, Philip M.

    2008-06-01

    The goal of radiation therapy is to achieve maximal therapeutic benefit expressed in terms of a high probability of local control of disease with minimal side effects. Physically this often equates to the delivery of a high dose of radiation to the tumour or target region whilst maintaining an acceptably low dose to other tissues, particularly those adjacent to the target. Techniques such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery and computer planned brachytherapy provide the means to calculate the radiation dose delivery to achieve the desired dose distribution. Imaging is an essential tool in all state of the art planning and delivery techniques: (i) to enable planning of the desired treatment, (ii) to verify the treatment is delivered as planned and (iii) to follow-up treatment outcome to monitor that the treatment has had the desired effect. Clinical imaging techniques can be loosely classified into anatomic methods which measure the basic physical characteristics of tissue such as their density and biological imaging techniques which measure functional characteristics such as metabolism. In this review we consider anatomical imaging techniques. Biological imaging is considered in another article. Anatomical imaging is generally used for goals (i) and (ii) above. Computed tomography (CT) has been the mainstay of anatomical treatment planning for many years, enabling some delineation of soft tissue as well as radiation attenuation estimation for dose prediction. Magnetic resonance imaging is fast becoming widespread alongside CT, enabling superior soft-tissue visualization. Traditionally scanning for treatment planning has relied on the use of a single snapshot scan. Recent years have seen the development of techniques such as 4D CT and adaptive radiotherapy (ART). In 4D CT raw data are encoded with phase information and reconstructed to yield a set of scans detailing motion through the breathing, or cardiac, cycle. In ART a set of

  20. Breast cellulitis after conservative surgery and radiotherapy

    SciTech Connect

    Rescigno, J.; McCormick, B.; Brown, A.E.; Myskowski, P.L. )

    1994-04-30

    Cellulitis is a previously unreported complication of conservative surgery and radiation therapy for early stage breast cancer. Patients who presented with breast cellulitis after conservative therapy are described. Eleven patients that developed cellulitis of the breast over a 38-month period of observation are the subject of this report. Clinical characteristics of patients with cellulitis and their treatment and outcome are reported. Potential patient and treatment-related correlates for the development of cellulitis are analyzed. The risk of cellulitis persists years after initial breast cancer therapy. The clinical course of the patients was variable: some patients required aggressive, long-duration antibiotic therapy, while others had rapid resolution with antibiotics. Three patients suffered from multiple episodes of cellulitis. Patients with breast cancer treated with conservative surgery and radiotherapy are at risk for breast cellulitis. Systematic characterization of cases of cellulitis may provide insight into diagnosis, prevention, and more effective therapy for this uncommon complication. 15 refs., 1 fig., 2 tabs.

  1. Radiotherapy and Antiangiogenic TM in Lung Cancer

    PubMed Central

    Khan, Mohamed K; Miller, Meredith W; Taylor, Jeremy; Gill, Navkiranjit K; Dick, Robert D; Van Golen, Kenneth; Brewer, George J; Merajver, Sofia D

    2002-01-01

    Abstract Tetrathiomolybdate (TM) is a potent nontoxic orally delivered copper complexing agent under development for the last several years for the treatment of Wilson's disease. It has been shown to block angiogenesis in primary and metastatic tumors. Therefore, the combination of cytotoxic radiotherapy (RT) and antiangiogenic TM could target both the existing tumor and the tumor microvasculature in a comprehensive strategy. Using a Lewis lung high metastatic (LLHM) carcinoma mouse tumor model, we demonstrate that the combination of TM and RT is more effective than either used as monotherapy. We also show that their therapeutic effects are additive, with no additional toxicity. We show that TM has no significant cytotoxicity in vitro against LLHM tumor cells, further supporting the antiangiogenic mechanism for its action. PMID:11896571

  2. Targeted Radiotherapy of Estrogen Receptor Positive Tumors

    SciTech Connect

    Raghavan Rajagopalan

    2006-08-31

    The overall objectives of the proposal were to develop estrogen receptor (ER) binding small molecule radiopharmaceuticals for targeted radiotherapy of ER positive (ER+) tumors. In particular, this proposal focused on embedding a {sup 186,188}Re or a {sup 32}P radionuclide into an estrogen steroidal framework by isosteric substitution such that the resulting structure is topologically similar to the estrogen (estrogen mimic). The estrogen mimic molecules expected to bind to the ER and exhibit biodistribution akin to that of native estrogen due to structural mimicry. It is anticipated that the {sup 186,188}Re- or a {sup 32}P-containing estrogen mimics will be useful for targeted molecular radiotherapy of ER+ tumors. It is well established that the in vivo target tissue uptake of estrogen like steroidal molecules is related to the binding of the steroids to sex hormone binding globulin (SHBG). SHBG is important in the uptake of estrogens and testosterone in target tissues by SHBG receptors on the cell surface. However, hitherto the design of estrogen like small molecule radiopharmaceuticals was focused on optimizing ER binding characteristics without emphasis on SHBG binding properties. Consequently, even the molecules with good ER affinity in vitro, performed poorly in biodistribution studies. Based on molecular modeling studies the proposal focused on developing estrogen mimics 1-3 which were topologically similar to native estrogens, and form hydrogen bonds in ER and SHBG in the same manner as those of native estrogens. To this end the technical objectives of the proposal focused on synthesizing the rhenium-estrone and estradiol mimics 1 and 2 respectively, and phosphorous estradiol mimic 3 and to assess their stability and in vitro binding characteristics to ER and SHBG.

  3. Use of Postmastectomy Radiotherapy in Older Women

    SciTech Connect

    Smith, Benjamin D. Haffty, Bruce G.; Smith, Grace L.; Hurria, Arti; Buchholz, Thomas A.; Gross, Cary P.

    2008-05-01

    Purpose: Clinical trials and guidelines published between 1997 and 2001 concluded that postmastectomy radiotherapy (PMRT) improves overall survival for women with high-risk breast cancer. However, the effect of these findings on current practice is not known. Using the Surveillance, Epidemiology, and End Results-Medicare cohort, we sought to characterize the adoption of PMRT from 1992 to 2002 and identify risk factors for PMRT omission among high-risk older patients. Methods and Materials: We identified 28,973 women aged {>=}66 years who had been treated with mastectomy for invasive breast cancer between 1992 and 2002. Trends in the adoption of PMRT for low- (T1-T2N0), intermediate- (T1-T2N1), and high- (T3-T4 and/or N2-N3) risk patients were characterized using a Monte Carlo permutation algorithm. Multivariate logistic regression identified the risk factors for PMRT omission and calculated the adjusted use rates. Results: Postmastectomy radiotherapy use increased gradually and consistently for low-risk (+2.16%/y) and intermediate-risk (+7.20%/y) patients throughout the study interval. In contrast, PMRT use for high-risk patients increased sharply between 1996 and 1997 (+30.99%/y), but subsequently stabilized. Between 1998 and 2002, only 53% of high-risk patients received PMRT. The risk factors for PMRT omission included advanced age, moderate to severe comorbidity, smaller tumor size, fewer positive lymph nodes, and geographic region, with adjusted use rates ranging from 63.5% in San Francisco to 44.9% in Connecticut. Conclusion: Among the high-risk patients, PMRT use increased sharply in 1997 after the initial clinical trial publication. Despite subsequent guidelines recommending the use of PMRT, no further increase in PMRT use has occurred, and nearly 50% of high-risk patients still do not receive PMRT.

  4. Statistical process control for radiotherapy quality assurance.

    PubMed

    Pawlicki, Todd; Whitaker, Matthew; Boyer, Arthur L

    2005-09-01

    Every quality assurance process uncovers random and systematic errors. These errors typically consist of many small random errors and a very few number of large errors that dominate the result. Quality assurance practices in radiotherapy do not adequately differentiate between these two sources of error. The ability to separate these types of errors would allow the dominant source(s) of error to be efficiently detected and addressed. In this work, statistical process control is applied to quality assurance in radiotherapy for the purpose of setting action thresholds that differentiate between random and systematic errors. The theoretical development and implementation of process behavior charts are described. We report on a pilot project is which these techniques are applied to daily output and flatness/symmetry quality assurance for a 10 MV photon beam in our department. This clinical case was followed over 52 days. As part of our investigation, we found that action thresholds set using process behavior charts were able to identify systematic changes in our daily quality assurance process. This is in contrast to action thresholds set using the standard deviation, which did not identify the same systematic changes in the process. The process behavior thresholds calculated from a subset of the data detected a 2% change in the process whereas with a standard deviation calculation, no change was detected. Medical physicists must make decisions on quality assurance data as it is acquired. Process behavior charts help decide when to take action and when to acquire more data before making a change in the process.

  5. Intensity-Modulated Radiotherapy for Pancreatic Adenocarcinoma

    SciTech Connect

    Abelson, Jonathan A.; Murphy, James D.; Minn, Ann Yuriko; Chung, Melody; Fisher, George A.; Ford, James M.; Kunz, Pamela; Norton, Jeffrey A.; Visser, Brendan C.; Poultsides, George A.; Koong, Albert C.; Chang, Daniel T.

    2012-03-15

    Purpose: To report the outcomes and toxicities in patients treated with intensity-modulated radiotherapy (IMRT) for pancreatic adenocarcinoma. Methods and Materials: Forty-seven patients with pancreatic adenocarcinoma were treated with IMRT between 2003 and 2008. Of these 47 patients, 29 were treated adjuvantly and 18 definitively. All received concurrent 5-fluorouracil chemotherapy. The treatment plans were optimized such that 95% of the planning target volume received the prescription dose. The median delivered dose for the adjuvant and definitive patients was 50.4 and 54.0 Gy, respectively. Results: The median age at diagnosis was 63.9 years. For adjuvant patients, the 1- and 2-year overall survival rate was 79% and 40%, respectively. The 1- and 2-year recurrence-free survival rate was 58% and 17%, respectively. The local-regional control rate at 1 and 2 years was 92% and 80%, respectively. For definitive patients, the 1-year overall survival, recurrence-free survival, and local-regional control rate was 24%, 16%, and 64%, respectively. Four patients developed Grade 3 or greater acute toxicity (9%) and four developed Grade 3 late toxicity (9%). Conclusions: Survival for patients with pancreatic cancer remains poor. A small percentage of adjuvant patients have durable disease control, and with improved therapies, this proportion will increase. Systemic therapy offers the greatest opportunity. The present results have demonstrated that IMRT is well tolerated. Compared with those who received three-dimensional conformal radiotherapy in previously reported prospective clinical trials, patients with pancreatic adenocarcinoma treated with IMRT in our series had improved acute toxicity.

  6. Evaluation of Coplanar Partial Left Breast Irradiation Using Tomotherapy-Based Topotherapy

    SciTech Connect

    McIntosh, Alyson; Read, Paul W.; Khandelwal, Shiv R.; Arthur, Douglas W.; Turner, A. Benton C.; Ruchala, Kenneth J.; Olivera, Gustavo H.; Jeswani, Sam; Sheng, Ke

    2008-06-01

    Purpose: To investigate the use of topotherapy for accelerated partial breast irradiation through field-design optimization and dosimetric comparison to linear accelerator-based three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT). Methods and Materials: Hypothetical 3-cm lumpectomy sites were contoured in each quadrant of a left breast by using dosimetric guidelines from the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 protocol. Coplanar intensity-modulated topotherapy treatment plans were optimized by using two-, three-, four-, five-, and seven-field arrangements for delivery by the tomotherapy unit with fixed gantry angles. Optimized noncoplanar five-field 3D-CRT and IMRT were compared with corresponding topotherapy plans. Results: On average, 99.5% {+-} 0.5% of the target received 100% of the prescribed dose for all topotherapy plans. Average equivalent uniform doses ranged from 1.20-2.06, 0.79-1.76, and 0.10-0.29 Gy for heart, ipsilateral lung, and contralateral lung, respectively. Average volume of normal breast exceeding 90% of the prescription and average area of skin exceeding 35 Gy were lowest for five-field plans. Average uniformity indexes for five-field plans using 3D-CRT, IMRT, and topotherapy were 1.047, 1.050, and 1.040, respectively. Dose-volume histograms and calculated equivalent uniform doses of all three techniques illustrate clinically equivalent doses to ipsilateral breast, lung, and heart. Conclusions: This dosimetric evaluation for a single patient shows that coplanar partial breast topotherapy provides good target coverage with exceptionally low dose to organs at risk. Use of more than five fields provided no additional dosimetric advantage. A comparison of five-field topotherapy to 3D-CRT and IMRT for accelerated partial breast irradiation illustrates equivalent target conformality and uniformity.

  7. Three-Dimensional Conformal Radiation Therapy for Esophageal Squamous Cell Carcinoma: Is Elective Nodal Irradiation Necessary?

    SciTech Connect

    Zhao Kuaile; Ma Jinbo; Liu Guang; Wu Kailiang; Shi Xuehui; Jiang Guoliang

    2010-02-01

    Purpose: To evaluate the local control, survival, and toxicity associated with three-dimensional conformal radiotherapy (3D-CRT) for squamous cell carcinoma (SCC) of the esophagus, to determine the appropriate target volumes, and to determine whether elective nodal irradiation is necessary in these patients. Methods and Materials: A prospective study of 3D-CRT was undertaken in patients with esophageal SCC without distant metastases. Patients received 68.4 Gy in 41 fractions over 44 days using late-course accelerated hyperfractionated 3D-CRT. Only the primary tumor and positive lymph nodes were irradiated. Isolated out-of-field regional nodal recurrence was defined as a recurrence in an initially uninvolved regional lymph node. Results: All 53 patients who made up the study population tolerated the irradiation well. No acute or late Grade 4 or 5 toxicity was observed. The median survival time was 30 months (95% confidence interval, 17.7-41.8). The overall survival rate at 1, 2, and 3 years was 77%, 56%, and 41%, respectively. The local control rate at 1, 2, and 3 years was 83%, 74%, and 62%, respectively. Thirty-nine of the 53 patients (74%) showed treatment failure. Seventeen of the 39 (44%) developed an in-field recurrence, 18 (46%) distant metastasis with or without regional failure, and 3 (8%) an isolated out-of-field nodal recurrence only. One patient died of disease in an unknown location. Conclusions: In patients treated with 3D-CRT for esophageal SCC, the omission of elective nodal irradiation was not associated with a significant amount of failure in lymph node regions not included in the planning target volume. Local failure and distant metastases remained the predominant problems.

  8. Differences in Effective Target Volume Between Various Techniques of Accelerated Partial Breast Irradiation

    SciTech Connect

    Shaitelman, Simona F.; Vicini, Frank A.; Grills, Inga S.; Martinez, Alvaro A.; Yan Di; Kim, Leonard H.

    2012-01-01

    Purpose: Different cavity expansions are used to define the clinical target volume (CTV) for accelerated partial breast irradiation (APBI) delivered via balloon brachytherapy (1 cm) vs. three-dimensional conformal radiotherapy (3D-CRT) (1.5 cm). Previous studies have argued that the CTVs generated by these different margins are effectively equivalent. In this study, we use deformable registration to assess the effective CTV treated by balloon brachytherapy on clinically representative 3D-CRT planning images. Methods and Materials: Ten patients previously treated with the MammoSite were studied. Each patient had two computed tomography (CT) scans, one acquired before and one after balloon implantation. In-house deformable registration software was used to deform the MammoSite CTV onto the balloonless CT set. The deformed CTV was validated using anatomical landmarks common to both CT scans. Results: The effective CTV treated by the MammoSite was on average 7% {+-} 10% larger and 38% {+-} 4% smaller than 3D-CRT CTVs created using uniform expansions of 1 and 1.5 cm, respectively. The average effective CTV margin was 1.0 cm, the same as the actual MammoSite CTV margin. However, the effective CTV margin was nonuniform and could range from 5 to 15 mm in any given direction. Effective margins <1 cm were attributable to poor cavity-balloon conformance. Balloon size relative to the cavity did not significantly correlate with the effective margin. Conclusion: In this study, the 1.0-cm MammoSite CTV margin treated an effective volume that was significantly smaller than the 3D-CRT CTV based on a 1.5-cm margin.

  9. Applications of synchrotron X-rays to radiotherapy

    NASA Astrophysics Data System (ADS)

    Blattmann, H.; Gebbers, J.-O.; Bräuer-Krisch, E.; Bravin, A.; Le Duc, G.; Burkard, W.; Di Michiel, M.; Djonov, V.; Slatkin, D. N.; Stepanek, J.; Laissue, J. A.

    2005-08-01

    Radiotherapy is among the most useful treatments of cancer. Penetrating radiation (ionizing particles or bremsstrahlung photons) is aimed toward the tumor-bearing target, gradually delivering as high radiation to it as is usefully suppressive of tumor growth, yet tolerated by normal vital tissues inevitably irradiated with the tumor. The high collimation and dose rate of synchrotron X-ray beams, even when monochromatized, favor radiotherapy. Photon activation therapy, tomotherapy, microbeam radiation therapy, and radiosurgery mediated by synchrotron wigglers are conceptually promising for difficult tumors. Radiotherapy of malignant brain tumors in rats has been encouraging, but suitable beam lines exist at only a few research facilities and much basic work must be done before the promise of synchrotron-based radiotherapy can be realized clinically.

  10. [Clinical to planning target volume margins in prostate cancer radiotherapy].

    PubMed

    Ramiandrisoa, F; Duvergé, L; Castelli, J; Nguyen, T D; Servagi-Vernat, S; de Crevoisier, R

    2016-10-01

    The knowledge of inter- and intrafraction motion and deformations of the intrapelvic target volumes (prostate, seminal vesicles, prostatectomy bed and lymph nodes) as well as the main organs at risk (bladder and rectum) allow to define rational clinical to planning target volume margins, depending on the different radiotherapy techniques and their uncertainties. In case of image-guided radiotherapy, prostate margins and seminal vesicles margins can be between 5 and 10mm. The margins around the prostatectomy bed vary from 10 to 15mm and those around the lymph node clinical target volume between 7 and 10mm. Stereotactic body radiotherapy allows lower margins, which are 3 to 5mm around the prostate. Image-guided and stereotactic body radiotherapy with adequate margins allow finally moderate or extreme hypofractionation.

  11. Evaluation of air photoactivation at linear accelerators for radiotherapy.

    PubMed

    Tana, Luigi; Ciolini, Riccardo; Ciuffardi, Eva; Romei, Chiara; d'Errico, Francesco

    2015-06-01

    High-energy x-rays produced by radiotherapy accelerators operating at potentials above 10 MV may activate the air via (γ, n) reactions with both oxygen and nitrogen. While the activation products are relatively short-lived, personnel entering the accelerator room may inhale some radioactive air, which warrants internal dosimetry assessments. This work illustrates a method based on the use of ammonium nitrate solutions for the evaluation of photon-induced air activation and for the estimate of internal doses to radiotherapy personnel. Air activation and internal dosimetry assessments based on our method are presented for some widespread radiotherapy linear accelerator models. Our results indicate that the equivalent dose to the lungs of radiotherapy personnel is negligible for beam energies below 18 MeV.

  12. Stereotactic body radiotherapy in lung cancer: an update *

    PubMed Central

    Abreu, Carlos Eduardo Cintra Vita; Ferreira, Paula Pratti Rodrigues; de Moraes, Fabio Ynoe; Neves, Wellington Furtado Pimenta; Gadia, Rafael; Carvalho, Heloisa de Andrade

    2015-01-01

    Abstract For early-stage lung cancer, the treatment of choice is surgery. In patients who are not surgical candidates or are unwilling to undergo surgery, radiotherapy is the principal treatment option. Here, we review stereotactic body radiotherapy, a technique that has produced quite promising results in such patients and should be the treatment of choice, if available. We also present the major indications, technical aspects, results, and special situations related to the technique. PMID:26398758

  13. [Radiotherapy and implantable medical device: example of infusion pumps].

    PubMed

    Abrous-Anane, S; Benhassine, S; Lopez, S; Cristina, K; Mazeron, J-J

    2013-12-01

    Indication for radiotherapy is often questioned for patients equipped with implantable medical devices like infusion pumps as the radiation tolerance is poor or not known. We report here on the case of a patient who we treated with pelvic radiotherapy for cervical cancer and who had an infusion pump in iliac fossa. We conducted a series of tests on five identical pumps that insured that the treatment protocol is harmless to the implanted device.

  14. Radiochromic Film Dosimetry and its Applications in Radiotherapy

    SciTech Connect

    Williams, Matthew; Metcalfe, Peter

    2011-05-05

    Radiochromic film can be a fast and inexpensive means for performing accurate quantitative radiation dosimetry. The development of new radiochromic compositions that have greater dose sensitivity and fewer environmental dependencies has led to an ever increasing use of the film in radiotherapy applications. In this report the various physical and dosimetric properties of radiochromic film are presented and the strategies to adequately manage these properties when using radiochromic film for radiotherapy applications are discussed.

  15. Implementing radiotherapy in Africa: Focus on the needs in Rwanda.

    PubMed

    Kamanzi, J-B; Adeduntan, R; Antoni, D; Musafiri, S; Noël, G

    2016-05-01

    Cancer care is a concern in low- and middle-income countries. The needs of structure to treat patients are huge. Because of the cost of radiotherapy, and the need for highly specialized workers, providing radiation therapy in these nations is a challenge. However, some solutions exist that can dramatically improve future care. In this article, we reviewed the plight of cancer treatment organization in Africa, and more specifically, the status of radiotherapy needs and concerns within Rwanda.

  16. PET/CT and radiotherapy in prostate cancer.

    PubMed

    De Jong, I J; De Haan, T D; Wiegman, E M; Van Den Bergh, A C M; Pruim, J; Breeuwsma, A J

    2010-10-01

    Radiotherapy is one of the corner stone treatments for patients with prostate cancer. Especially for locally advanced tumors radiotherapy +/- adjuvant androgen deprivation treatment is standard of care. This brings up the need for accurate assessment of extra prostatic tumor growth and/or the presence of nodal metastases for selection of the optimal radiation dose and treatment volume. Morphological imaging like transrectal ultra sound, computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used but are limited in their accuracy in detecting extra prostatic extension and nodal metastases. In this article we present a structured review of the literature on positron emission tomography (PET)/CT and radiotherapy in prostate cancer patients with emphasis on: 1) the pretreatment assessment of extra prostatic tumor extension, nodal and distant metastases; 2) the intraprostatic tumor characterization and radiotherapy treatment planning; and 3) treatment evaluation and the use of PET/CT in guidance of salvage treatment. PET/CT is not an appropriate imaging technique for accurate T-staging of prostate cancer prior to radiotherapy. Although macroscopic disease beyond the prostatic capsule and into the periprostatic fat or in seminal vesicle is often accurately detected, the microscopic extension of prostate cancer remains undetected. Choline PET/CT holds a great potential as a single step diagnostic procedure of lymph nodes and skeleton, which could facilitate radiotherapy treatment planning. At present the use of PET/CT for treatment planning in radiotherapy is still experimental. Choline PET based tumor delineation is not yet standardized and different segmentation-algorithms are under study. However, dose escalation using dose-painting is feasible with only limited increases of the doses to the bladder and rectum wall. PET/CT using either acetate or choline is able to detect recurrent prostate cancer after radiotherapy but stratification of patients

  17. Treatment of ameloblastoma and ameloblastic carcinoma with radiotherapy.

    PubMed

    Kennedy, William R; Werning, John W; Kaye, Frederic J; Mendenhall, William M

    2016-10-01

    The purpose of this study is to report our institutional experience using radiotherapy in the treatment of ameloblastoma and ameloblastic carcinoma. Three patients with ameloblastoma and 3 patients with ameloblastic carcinoma were treated with radiotherapy alone (2 patients) or surgery and postoperative radiotherapy (4 patients) at the University of Florida between 1973 and 2007. Follow-up ranged from 4.0 to 13.1 years with a median of 7.8 years. Radiotherapy complications were scored using the Common Terminology Criteria for Adverse Events, version 4.0. Local control was achieved in 4 of the 6 patients. One patient treated with RT alone for an unresectable ameloblastoma developed a local recurrence and metastases in both the cervical lymph nodes and lungs, but had excellent response to dual BRAF/MEK inhibition with dabrafenib and trametinib. Another patient treated with surgery and postoperative radiotherapy for an ameloblastic carcinoma recurred locally without metastasis, but was not salvaged. No significant treatment-related complications were observed. For patients with local recurrence or inadequate margins after surgery, adjuvant radiotherapy provides the potential for disease control. In the setting of metastatic disease, targeted therapies may provide an additional opportunity for salvage.

  18. Complete response of myeloid sarcoma with cardiac involvement to radiotherapy

    PubMed Central

    Yang, Wen-Chi; Yao, Ming; Chen, Yu-Hsuan

    2016-01-01

    We present a rare case of intracardiac myeloid sarcoma (MS) of acute myeloid leukemia (AML) and who responds completely well to low-dose radiotherapy. This 19-year-old young man initially presented with AML and received standard chemotherapy followed by allogeneic hematopoietic stem cell transplantation (HSCT). However, he developed intracardiac isolated MS relapse with the presentation of exertional dyspnea and superior vena cava (SVC) syndrome 3 years later. He then received radiotherapy with 24 Gy at a 12 daily fractions using forward “field in field” intensity modulated radiotherapy technique. He dramatically had improved clinical symptoms, and complete remission was achieved one month after completing radiotherapy. Our result is in line with anecdotal case reports showed that radiotherapy with 15 Gy in 10 fractions or with 24 Gy in 12 fractions resulted in good response and less toxicity of 2 cases of MS with cardiac involvement. These results indicate that a modest radiotherapy dose, 24 Gy, achieves good local control of MS with cardiac involvement. PMID:27293853

  19. Monte Carlo role in radiobiological modelling of radiotherapy outcomes

    NASA Astrophysics Data System (ADS)

    El Naqa, Issam; Pater, Piotr; Seuntjens, Jan

    2012-06-01

    Radiobiological models are essential components of modern radiotherapy. They are increasingly applied to optimize and evaluate the quality of different treatment planning modalities. They are frequently used in designing new radiotherapy clinical trials by estimating the expected therapeutic ratio of new protocols. In radiobiology, the therapeutic ratio is estimated from the expected gain in tumour control probability (TCP) to the risk of normal tissue complication probability (NTCP). However, estimates of TCP/NTCP are currently based on the deterministic and simplistic linear-quadratic formalism with limited prediction power when applied prospectively. Given the complex and stochastic nature of the physical, chemical and biological interactions associated with spatial and temporal radiation induced effects in living tissues, it is conjectured that methods based on Monte Carlo (MC) analysis may provide better estimates of TCP/NTCP for radiotherapy treatment planning and trial design. Indeed, over the past few decades, methods based on MC have demonstrated superior performance for accurate simulation of radiation transport, tumour growth and particle track structures; however, successful application of modelling radiobiological response and outcomes in radiotherapy is still hampered with several challenges. In this review, we provide an overview of some of the main techniques used in radiobiological modelling for radiotherapy, with focus on the MC role as a promising computational vehicle. We highlight the current challenges, issues and future potentials of the MC approach towards a comprehensive systems-based framework in radiobiological modelling for radiotherapy.

  20. Nutritional consequences of the radiotherapy of head and neck cancer

    SciTech Connect

    Chencharick, J.D.; Mossman, K.L.

    1983-03-01

    Nutrition-related complications of radiotherapy were evaluated in 74 head and neck cancer patients. Subjective changes of mouth dryness, taste, dysphagia, appetite, and food preferences were determined by questionnaire before and at weekly intervals during curative radiotherapy. Changes in body weight during therapy were also recorded. In addition, 24-hour dietary histories were taken from eight patients at the beginning and end of treatment. Results of the study indicate that patients were subjectively aware of nutritional problems prior to therapy and that therapy exacerbated these problems. As many as 25% of the patients experienced oral complications such as taste loss and/or dry mouth prior to initiation of radiotherapy. By the end of radiotherapy, over 80% of the patients were aware of oral and nutritional problems. Patients had an average weight loss of 5 kg prior to therapy; this loss of weight did not change during therapy. Diet histories of eight patients indicate significant caloric deficiencies early and late in radiotherapy. The oral and nutritional problems experienced by patients, even prior to therapy, support the idea that nutritional evaluation and maintenance are important not only during therapy, but prior to radiotherapy as well. Nutritional evaluation should be made a routine, integral part of therapy for every cancer patient.

  1. Radiotherapy in Glioblastoma: the Past, the Present and the Future.

    PubMed

    Gzell, C; Back, M; Wheeler, H; Bailey, D; Foote, M

    2017-01-01

    The aim of this review is to explore the changing utility of radiotherapy in the treatment of patients with glioblastoma over the past 60 years. Together with surgery, radiotherapy has always been the cornerstone of treatment of glioblastoma, but techniques have significantly advanced over this time. The exploration of early two-dimensional techniques, investigation of dose escalation, concomitant chemotherapy and modern techniques, including intensity-modulated radiotherapy, image-guided radiotherapy, and volumetric-modulated arc therapy will be covered. In addition, current controversies including decreasing margin size, re-irradiation, treatment of elderly patients, and novel imaging tracers will be discussed. Future directions including immunotherapy and tumour treating fields are examined. Radiotherapy-based treatments cannot rely solely on advances in chemotherapy or immunotherapy to improve the overall survival of patients with glioblastoma. Radiation oncology needs to continue to develop and improve the delivery, target definition, and dose of radiotherapy to these patients to improve their survival and the toxicity associated with treatment.

  2. 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

  3. Results of radiotherapy in non round cell spinal metastasis.

    PubMed

    Kraiwattanapong, Chaiwat; Buranapanitkit, Boonsin; Kiriratnikom, Theerasan

    2004-03-01

    Spinal metastases are commonly encountered by physicians in a variety of clinical fields. There are some controversies in choice of treatment between surgery and radiotherapy. This report is a study of the outcomes of radiotherapy for metastatic nonround cell tumors of the spine. Medical records and films of 31 patients who were treated with radiotherapy at Songklanakarind Hospital were retrospectively reviewed. The most common primary tumors were prostate and breast. One patient had spinal metastases from malignant serous cystadenoma of the fallopian tube of which no previous report has been published. This patient had excellent results after radiotherapy. Back and neck pain were the primary symptoms of the patients, while motor or sensory deficits (or both) were found in 58 per cent of the cases. Seven patients had neurological recovery and 18 patients had pain relief after radiotherapy. Cause of compression is the only factor effecting the result from univariate and multivariate analysis. Spinal cord compressed by a tumor had a better recovery than those which were compressed by a bony fragment or intervertebral disc. The authors concluded that radiotherapy remains a good treatment for patient with non round cell spinal metastasis. Cause of spinal cord compression is the only factor predicting the result of treatment.

  4. Pectoral stretching program for women undergoing radiotherapy for breast cancer.

    PubMed

    Lee, T S; Kilbreath, S L; Refshauge, K M; Pendlebury, S C; Beith, J M; Lee, M J

    2007-05-01

    Surgery and radiotherapy commonly cause adverse musculoskeletal problems, particularly loss of strength and range of motion, in the upper quadrant of breast cancer patients. Few well-designed studies have investigated whether these impairments can be prevented. Stretching is an effective technique for increasing range of motion, hence the aim of this study was to investigate whether a stretching program reduced acute musculoskeletal impairments in patients undergoing radiotherapy for breast cancer. Sixty-four women were recruited prior to commencement of radiotherapy following breast cancer surgery. Participants were randomised to either a control or stretch group. Participants in both groups were reviewed by the physical therapist on a weekly basis for approximately 6 weeks, and were given general information about skin care and lymphedema. The control group received no advice about exercise. The stretch group received instruction on low-load, prolonged pectoral stretches, which were to be performed daily and were checked at weekly visits. Shoulder range of motion, strength, arm circumference, and quality of life measurements were taken prior to, and at completion of radiotherapy, and at 7 months after radiotherapy. There was no difference in any outcome between groups. Breast symptoms increased for both groups during radiotherapy, without loss of strength or range of movement. The incidence of lymphedema during the study was low for both groups and did not differ between groups. The pectoral stretching program did not influence the outcomes measured because the symptoms reported by patients were not a consequence of contracture.

  5. 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.

  6. New Methods for Targeted Alpha Radiotherapy

    NASA Astrophysics Data System (ADS)

    Robertson, J. David

    2014-03-01

    Targeted radiotherapies based on alpha emitters are a promising alternative to beta emitting radionuclides. Because of their much shorter range, targeted α-radiotherapy (TAT) agents have great potential for application to small, disseminated tumors and micro metastases and treatment of hematological malignancies consisting of individual, circulating neoplastic cells. A promising approach to TAT is the use of the in vivo α-generator radionuclides 223 = 11.4 d) and 225Ac 1/2 = 10.0 d). In addition to their longer half-lives, these two isotopes have the potential of dramatically increasing the therapeutic efficacy of TAT as they each emit four α particles in their decay chain. This principle has recently been exploited in the development of Xofigo®, the first TAT agent approved for clinical use by the U.S. FDA. Xofigo, formulated as 223RaCl2, is used for treatment of metastatic bone cancer in men with castration-resistant prostate cancer. TAT with 223Ra works, however, only in the case of bone cancer because radium, as a chemical analogue of calcium, efficiently targets bone. In order to bring the benefits of TAT with 223Ra or 225Ac to other tumor types, a new delivery method must be devised. Retaining the in vivo α generator radionuclides at the target site through the decay process is one of the major challenges associated with the development of TAT. Because the recoil energy of the daughter radionuclides from the α-emission is ~ 100 keV - a value which is four orders of magnitude greater than the energy of a covalent bond - the daughters will not remain bound to the bioconjugate at the targeting site. Various approaches have been attempted to achieve retention of the α-generator daughter radionuclides at the target site, including incorporation of the in vivo generator into liposomes and fullerenes. Unfortunately, to date single wall liposomes and fullerenes are able to retain less than 10% of the daughter radionuclides. We have recently demonstrated that a

  7. Concomitant use of radiotherapy and two topoisomerase inhibitors to treat adult T-cell leukemia with a radiotherapy-resistant bulky disease: a case series.

    PubMed

    Obama, Kosuke

    2014-01-01

    Concomitant chemoradiotherapy is established as the standard treatment to improve the prognosis of several types of solid tumor, but has not been the general practice for hematological malignancies. Here, I report two cases of adult T-cell leukemia (ATL) with a radiotherapy-resistant bulky disease treated with concomitant radiotherapy and two topoisomerase inhibitors: etoposide (VP-16) and irinotecan (CPT-11). Patient 1 was a 78-year-old man with chemotherapy-resistant inguinal bulky mass. Radiotherapy (total 40 Gy) for this inguinal lesion was started; however, the bulky disease was found to be resistant to radiotherapy and progressed. VP-16 and CPT-11 were administered in addition to radiotherapy (after a total of 20 Gy of radiotherapy). Patient 2 was a 71-year-old man with a solitary bulky mass in left cervical lesion. Various previous chemotherapy and radiotherapy approaches had not been able to control the disease. Six months after first radiotherapy, the bulky disease rapidly progressed with the occurrence of pain. Second radiotherapy (30 Gy) was started with simultaneous administration of CPT-11 and VP-16. In both cases, the bulky disease gradually regressed and completely disappeared by the end of radiotherapy. Thus, flexible adaptation of concomitant chemoradiotherapy including two topoisomerase inhibitors may offer a potential therapeutic option for radiotherapy-resistant bulky diseases, even in hematological malignancies.

  8. Development of three-dimensional radiotherapy techniques in breast cancer

    NASA Astrophysics Data System (ADS)

    Coles, Charlotte E.

    Radiotherapy following conservation surgery decreases local relapse and death from breast cancer. Currently, the challenge is to minimise the morbidity caused by this treatment without losing efficacy. Despite many advances in radiation techniques in other sites of the body, the majority of breast cancer patients are still planned and treated using 2-dimensional simple radiotherapy techniques. In addition, breast irradiation currently consumes 30% of the UK's radiotherapy workload. Therefore, any change to more complex treatment should be of proven benefit. The primary objective of this research is to develop and evaluate novel radiotherapy techniques to decrease irradiation of normal structures and improve localisation of the tumour bed. I have developed a forward-planned intensity modulated (IMRT) breast radiotherapy technique, which has shown improved dosimetry results compared to standard breast radiotherapy. Subsequently, I have developed and implemented a phase III randomised controlled breast IMRT trial. This National Cancer Research Network adopted trial will answer an important question regarding the clinical benefit of breast IMRT. It will provide DNA samples linked with high quality clinical outcome data, for a national translational radiogenomics study investigating variation in normal tissue toxicity. Thus, patients with significant late normal tissue side effects despite good dose homogeneity will provide the best model for finding differences due to underlying genetics. I evaluated a novel technique using high definition free-hand 3-dimensional (3D) ultrasound in a phantom study, and the results suggested that this is an accurate and reproducible method for tumour bed localisation. I then compared recognised methods of tumour bed localisation with the 3D ultrasound method in a clinical study. The 3D ultrasound technique appeared to accurately represent the shape and spatial position of the tumour cavity. This tumour bed localisation research

  9. Waiting time for radiotherapy in women with cervical cancer

    PubMed Central

    do Nascimento, Maria Isabel; Azevedo e Silva, Gulnar

    2016-01-01

    ABSTRACT OBJECTIVE To describe the waiting time for radiotherapy for patients with cervical cancer. METHODS This descriptive study was conducted with 342 cervical cancer cases that were referred to primary radiotherapy, in the Baixada Fluminense region, RJ, Southeastern Brazil, from October 1995 to August 2010. The waiting time was calculated using the recommended 60-day deadline as a parameter to obtaining the first cancer treatment and considering the date at which the diagnosis was confirmed, the date of first oncological consultation and date when the radiotherapy began. Median and proportional comparisons were made using the Kruskal Wallis and Chi-square tests. RESULTS Most of the women (72.2%) began their radiotherapy within 60 days from the diagnostic confirmation date. The median of this total waiting time was 41 days. This median worsened over the time period, going from 11 days (1995-1996) to 64 days (2009-2010). The median interval between the diagnostic confirmation and the first oncological consultation was 33 days, and between the first oncological consultation and the first radiotherapy session was four days. The median waiting time differed significantly (p = 0.003) according to different stages of the tumor, reaching 56 days, 35 days and 30 days for women whose cancers were classified up to IIA; from IIB to IIIB, and IVA-IVB, respectively. CONCLUSIONS Despite most of the women having had access to radiotherapy within the recommended 60 days, the implementation of procedures to define the stage of the tumor and to reestablish clinical conditions took a large part of this time, showing that at least one of these intervals needs to be improved. Even though the waiting times were ideal for all patients, the most advanced cases were quickly treated, which suggests that access to radiotherapy by women with cervical cancer has been reached with equity. PMID:26786473

  10. 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.

  11. 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

  12. Present Status of Radiotherapy in Clinical Practice

    NASA Astrophysics Data System (ADS)

    Duehmke, Eckhart

    Aims of radiation oncology are cure from malignant diseases and - at the same time preservation of anatomy (e.g. female breast, uterus, prostate) and organ functions (e.g. brain, eye, voice, sphincter ani). At present, methods and results of clinical radiotherapy (RT) are based on experiences with natural history and radiobiology of malignant tumors in properly defined situations as well as on technical developments since World War II in geometrical and biological treatment planning in teletherapy and brachytherapy. Radiobiological research revealed tolerance limits of healthy tissues to be respected, effective total treatment doses of high cure probability depending on histology and tumor volume, and - more recently - altered fractionation schemes to be adapted to specific growth fractions and intrinsic radiosensitivities of clonogenic tumor cells. In addition, Biological Response Modifiers (BRM), such as cis-platinum, oxygen and hyperthermia may steepen cell survival curves of hypoxic tumor cells, others - such as tetrachiordekaoxid (TCDO) - may enhance repair of normal tissues. Computer assisted techniques in geometrical RT-planning based on individual healthy and pathologic anatomy (CT, MRT) provide high precision RT for well defined brain lesions by using dedicated linear accelerators (Stereotaxy). CT-based individual tissue compensators help with homogenization of distorted dose distributions in magna field irradiation for malignant lymphomas and with total body irradiation (TBI) before allogeneic bone marrow transplantation, e.g. for leukemia. RT with fast neutrons, Boron Neutron Capture Therapy (BNCT), RT with protons and heavy ions need to be tested in randomized trials before implementation into clinical routine.

  13. 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.

  14. Steroid requirements during radiotherapy for malignant gliomas.

    PubMed

    Marantidou, Athina; Levy, Christine; Duquesne, Alyette; Ursu, Renata; Bailon, Olivier; Coman, Irene; Belin, Catherine; Carpentier, Antoine F

    2010-10-01

    Radiotherapy (RT) is the standard treatment for high-grade gliomas. However, toxicity may develop during RT, such as brain edema or worsening of neurological symptoms. Surprisingly, no dedicated study had focused on steroid requirements during RT in adult patients with malignant gliomas. We evaluated prospectively all patients with malignant gliomas treated by RT in a single center from July 2006 to May 2009. Age, sex, initial Karnofsky performance status (KPS), tumor localization and histology, type of surgical resection, clinical target volume, total dose and duration of RT, concomitant treatment with temozolomide, and steroid dosage during RT and at 1 and 3 months after RT were recorded in all patients. Most of the 80 patients (70%) were already taking steroids before RT. Half of them (55%) required initiation or further steroids increase during RT. The median time to steroid increase was 8 days. Only 13% of patients remained free of steroids during RT, and the mean maximal dosage of prednisone was 55 ± 48 mg. At 3 months after RT, 29% of patients were free of steroids, and the mean prednisone dosage was 32 ± 50 mg. Unresected tumors and initial KPS ≤80% were the only variables associated with higher steroid requirements on multivariate analysis. In our series, almost all patients required steroids during RT. Poor initial KPS and biopsy were associated with higher steroid requirements.

  15. [Prostate localization systems for prostate radiotherapy].

    PubMed

    de Crevoisier, R; Lagrange, J-L; Messai, T; M'Barek, B; Lefkopoulos, D

    2006-11-01

    The development of sophisticated conformal radiation therapy techniques for prostate cancer, such as intensity-modulated radiotherapy, implies precise and accurate targeting. Inter- and intrafraction prostate motion can be significant and should be characterized, unless the target volume may occasionally be missed. Indeed, bony landmark-based portal imaging does not provide the positional information for soft-tissue targets (prostate and seminal vesicles) or critical organs (rectum and bladder). In this article, we describe various prostate localization systems used before or during the fraction: rectal balloon, intraprostatic fiducials, ultrasound-based localization, integrated CT/linear accelerator system, megavoltage or kilovoltage cone-beam CT, Calypso 4D localization system tomotherapy, Cyberknife and Exactrac X-Ray 6D. The clinical benefit in using such prostate localization tools is not proven by randomized studies and the feasibility has just been established for some of these techniques. Nevertheless, these systems should improve local control by a more accurate delivery of an increased prescribed dose in a reduced planning target volume.

  16. Fractionated Stereotactic Radiotherapy for Facial Nerve Schwannomas

    PubMed Central

    Shi, Wenyin; Jain, Varsha; Kim, Hyun; Champ, Colin; Jain, Gaurav; Farrell, Christopher; Andrews, David W.; Judy, Kevin; Liu, Haisong; Artz, Gregory; Werner-Wasik, Maria; Evans, James J.

    2015-01-01

    Purpose Data on the clinical course of irradiated facial nerve schwannomas (FNS) are lacking. We evaluated fractionated stereotactic radiotherapy (FSRT) for FNS. Methods Eight consecutive patients with FNS treated at our institution between 1998 and 2011 were included. Patients were treated with FSRT to a median dose of 50.4 Gy (range: 46.8–54 Gy) in 1.8 or 2.0 Gy fractions. We report the radiographic response, symptom control, and toxicity associated with FSRT for FNS. Results The median follow-up time was 43 months (range: 10–75 months). All patients presented with symptoms including pain, tinnitus, facial asymmetry, diplopia, and hearing loss. The median tumor volume was 1.57 cc. On the most recent follow-up imaging, five patients were noted to have stable tumor size; three patients had a net reduction in tumor volume. Additionally, six patients had improvement in clinical symptoms, one patient had stable clinical findings, and one patient had worsened House-Brackmann grade due to cystic degeneration. Conclusion FSRT treatment of FNS results in excellent control of growth and symptoms with a small rate of radiation toxicity. Given the importance of maintaining facial nerve function, FSRT could be considered as a primary management modality for enlarging or symptomatic FNS. PMID:26949592

  17. Chemically enhanced radiotherapy: visions for the future

    PubMed Central

    Susheela, Sridhar P.

    2016-01-01

    Radiotherapy (RT) is an important part of cancer management, with more than a third of all cancer cures being attributable to RT. Despite the advances in RT over the past century, the overall outcomes in a majority of malignancies are still unsatisfactory. There has been a constant endeavor to enhance the outcome of RT, and this has been in the form of altered fractionation, oxymimetic radiosensitizers, the use of concurrent chemotherapy, anti-angiogenic therapy and anti-growth factor receptor targeted therapies. This article presents a vision for the future, with emphasis upon emerging prospects which could enhance RT outcomes. Positive speculations regarding the use of immunological aspects, the use of nanoscale technology and the adoption of metronomic concurrent chemotherapy have been presented. Also, the potential with the use of low dose hyperradiosensitivity in enhancing chemotherapy outcomes too has been discussed. In this era of evidence based clinical practise, there exists a strong obsession towards the ‘present’ with ‘contempt towards the future’. Accepting the shortcomings of the existing modalities, there must be a strong zeal towards discovering better methodologies to enhance radiotherapeutic outcomes for the sake of a better future. PMID:26904574

  18. Second cancers following radiotherapy for cervical cancer

    SciTech Connect

    Kleinerman, R.A.; Curtis, R.E.; Boice, J.D. Jr.; Flannery, J.T.; Fraumeni, J.F. Jr.

    1982-11-01

    Incidence of second primary cancers was evaluated in 7,127 women with invasive cancer of the cervix uteri, diagnosed between 1935 and 1978, and followed up to 38 years (average, 8.9 yr) in Connecticut. Among 5,997 women treated with radiation, 449 developed second primary cancers compared with 313 expected (relative risk . 1.4) on the basis of rates from the Connecticut Tumor Registry. Excess incidence was noticeable 15 years or more after radiotherapy and attributed mostly to cancers of sites in or near the radiation field, especially the bladder, kidneys, rectum, corpus uteri, and ovaries. No excess was found for these sites among the 1,130 nonirradiated women. The ratio of observed to expected cancers for these sites did not vary appreciably by age at irradiation. The data suggested that high-dose pelvic irradiation was associated with increase in cancers of the bladder, kidneys, rectum, ovaries, corpus uteri, and non-Hodgkin's lymphoma but, apparently, not leukemia, Hodgkin's disease, breast cancer, or colon cancer.

  19. Hypnotherapy in radiotherapy patients: A randomized trial

    SciTech Connect

    Stalpers, Lukas J.A. . E-mail: l.stalpers@amc.uva.nl; Costa, Hanna C. da; Merbis, Merijn A.E.; Fortuin, Andries A.; Muller, Martin J.; Dam, Frits van

    2005-02-01

    Purpose: To determine whether hypnotherapy reduces anxiety and improves the quality of life in cancer patients undergoing curative radiotherapy (RT). Methods and materials: After providing written informed consent, 69 patients were randomized between standard curative RT alone (36 controls) and RT plus hypnotherapy (33 patients). Patients in the hypnotherapy group received hypnotherapy at the intake, before RT simulation, before the first RT session, and halfway between the RT course. Anxiety was evaluated by the State-Trait Anxiety Inventory DY-1 form at six points. Quality of life was measured by the Rand Medical Outcomes Study 36-item Health Survey (SF-36) at five points. Additionally, patients answered a questionnaire to evaluate their experience and the possible benefits of this research project. Results: No statistically significant difference was found in anxiety or quality of life between the hypnotherapy and control groups. However, significantly more patients in the hypnotherapy group indicated an improvement in mental (p < 0.05) and overall (p < 0.05) well-being. Conclusion: Hypnotherapy did not reduce anxiety or improve the quality of life in cancer patients undergoing curative RT. The absence of statistically significant differences between the two groups contrasts with the hypnotherapy patients' own sense of mental and overall well-being, which was significantly greater after hypnotherapy. It cannot be excluded that the extra attention by the hypnotherapist was responsible for this beneficial effect in the hypnotherapy group. An attention-only control group would be necessary to control for this effect.

  20. Stereotactic Body Radiotherapy for Oligometastatic Lung Tumors

    SciTech Connect

    Norihisa, Yoshiki; Nagata, Yasushi Takayama, Kenji; Matsuo, Yukinori; Sakamoto, Takashi; Sakamoto, Masato; Mizowaki, Takashi; Yano, Shinsuke; Hiraoka, Masahiro

    2008-10-01

    Purpose: Since 1998, we have treated primary and oligometastatic lung tumors with stereotactic body radiotherapy (SBRT). The term 'oligometastasis' is used to indicate a small number of metastases limited to an organ. We evaluated our clinical experience of SBRT for oligometastatic lung tumors. Methods and Materials: A total of 34 patients with oligometastatic lung tumors were included in this study. The primary involved organs were the lung (n = 15), colorectum (n = 9), head and neck (n = 5), kidney (n = 3), breast (n = 1), and bone (n = 1). Five to seven, noncoplanar, static 6-MV photon beams were used to deliver 48 Gy (n = 18) or 60 Gy (n = 16) at the isocenter, with 12 Gy/fraction within 4-18 days (median, 12 days). Results: The overall survival rate, local relapse-free rate, and progression-free rate at 2 years was 84.3%, 90.0%, and 34.8%, respectively. No local progression was observed in tumors irradiated with 60 Gy. SBRT-related pulmonary toxicities were observed in 4 (12%) Grade 2 cases and 1 (3%) Grade 3 case. Patients with a longer disease-free interval had a greater overall survival rate. Conclusion: The clinical result of SBRT for oligometastatic lung tumors in our institute was comparable to that after surgical metastasectomy; thus, SBRT could be an effective treatment of pulmonary oligometastases.

  1. Overview of Carbon-ion Radiotherapy

    NASA Astrophysics Data System (ADS)

    Tsujii, Hirohiko

    2017-01-01

    The outcome of radiotherapy depends on potential efficiency of accelerators and their related accessories. In charged particle therapy before the 1990s, accelerators that were primarily installed for physics research had been shared, which however had limited flexibility for clinical use. Therapy-dedicated facility was first constructed at Loma Linda University for PBT in 1990 and at NIRS for CIRT in 1993. Currently, there are more than 56 facilities for PBT, 6 for CIRT, and 6 for PBT/CIRT, and even more facilities are under construction or active planning. CIRT has beneficial property for cancer therapy because, as compared with photon therapy, it offers superior dose distributions by exhibiting a Bragg peak in the body and, as compared with PBT, it has higher radiobiological effectiveness. The number of potential candidates for charged particle therapy is estimated to range from 0.018% to 0.035% of all irradiated cancer patients. In CIRT at NIRS, Japan, more than 9,000 patients have been treated with promising results in non-SCC tumors and photon-resistant types of tumors at various sites. It is of note that in CIRT a significant reduction in overall treatment time and fractions has been successfully achieved.

  2. Radiotherapy treatments using Tsallis entropy statistical approach

    NASA Astrophysics Data System (ADS)

    D, Rodríguez-Pérez; O, Sotolongo-Grau; O, Sotolongo-Costa; C, Antoranz J.

    2014-03-01

    Several radiobiological models mimic the biologic effect of one single radiation dose on a living tissue. However, the actual fractionated radiotherapy requires accounting for a new magnitude, i.e., time. Here, we explore the biological consequences posed by the mathematical prolongation of a previous single radiation model to fractionated treatment. The survival fraction is obtained, together with the equivalent physical dose, in terms of a time dependent factor (similar to a repair coefficient) describing the tissue trend to recovering its radioresistance. The model describes how dose fractions add up to obtain the equivalent dose and how the repair coefficient poses a limit to reach an equivalent dose equal to the critical one that would completely annihilate the tumor. On the other hand, the surrounding healthy tissue is a limiting factor to treatment planning. This tissue has its own repair coefficient and thus should limit the equivalent dose of a treatment. Depending on the repair coefficient and the critical dose of each tissue, unexpected results (failure to fully remove the tumor) can be obtained. To illustrate these results and predictions, some realistic example calculations will be performed using parameter values within actual clinical ranges. In conclusion, the model warns about treatment limitations and proposes ways to overcome them.

  3. System Toward Automation in Radiotherapy Treatment: START

    NASA Astrophysics Data System (ADS)

    Cheng, Andrew Y. S.; Tsoi, Kenneth Y. P.

    1994-10-01

    START is a new automation system invented for nasopharyngeal carcinoma treatment. A laser scanner system capable of non-contact digitization of 3D surface is used to digitize the contours of the patient's face, shoulder and special landmark reference features of the patient. These features are stored in the computer in 3D digitized format. The digitized facial features with traced landmark reference features are used for fabrication of a true sized wood-particle laminates mould by a computer numerical controlled milling system. A Cobex mask is formed on this mould by using vacuum forming technique. With an image analysis and computer aided design system, the X-ray film with treatment window marked is traced automatically and converted to match the prescanned 3D information. A computer controlled 6-axis robot can precisely mark out the required areas on the Cobex cast for treatment. Finally, the patient receives radiotherapy treatment with the Cobex case as a positioning registration device. The new system will replace the manual procedure with better patient comfort, higher efficiency and enhanced accuracy.

  4. [Influence of radiotherapy on lymphocyte subpopulations].

    PubMed

    Ceschia, T; Beorchia, A; Guglielmi, R; Mandoliti, G; Fongione, S; Cereghini, M; Tonutti, E; Sala, P G; Pizzi, G

    1991-04-01

    The authors investigated the effects of radiation therapy on the immune system by studying lymphocyte subsets and other parameters in 32 patients undergoing radiation therapy for solid cancer. With monoclonal antibody techniques, we studied both T- and B-lymphocytes; cell suspensions were analyzed by means of a Facs Spectrum III Ortho (Ortho-Diagnostic) unit. The first control was performed right after the beginning of radiotherapy, when the dose to the patients was 50 Gy or higher. The second control was performed at 40 Gy because all patients received this dose. 30% of the patients exhibited lymphopenia from the beginning of the study; at 40 Gy the number of T-lymphocytes was low and helper/suppressor ratio was altered. A variable response of B-cells was observed, although all patients exhibited restoration of normal values at 6 months. Four patients only suffered from side-effects: a patient with tongue cancer presented oral mycosis, and a woman--treated for breast cancer--presented vaginal mycosis. Two cases of cystitis were also observed, after 18 Gy, in patients with uterine carcinoma undergoing pelvic irradiation. Disease progression was observed in 2 patients with head and neck cancer, while 3 patients died from lung cancer progression. Another one, with head and neck cancer, died because of heart failure.

  5. Effect of intensity-modulated radiotherapy versus two-dimensional conventional radiotherapy alone in nasopharyngeal carcinoma

    PubMed Central

    OuYang, Pu-Yun; Shi, Dingbo; Sun, Rui; Zhu, Yu-Jia; Xiao, Yao; Zhang, Lu-Ning; Zhang, Xu-Hui; Chen, Ze-Ying; Lan, Xiao-Wen; Tang, Jie; Gao, Yuan-Hong; Ma, Jun; Deng, Wuguo; Xie, Fang-Yun

    2016-01-01

    Background Albeit intensity-modulated radiotherapy (IMRT) is currently the recommended radiation technique in treating nasopharyngeal carcinoma, the effect of IMRT versus two-dimensional conventional radiotherapy (2DCRT) alone is still contradictory. Results In the original unmatched cohort of 1198 patients, IMRT obtained comparable 5-year overall survival (OS) (91.3% vs 87.1%, P = 0.120), locoregional relapse-free survival (LRFS) (92.3% vs 90.4%, P = 0.221) and distant metastasis-free survival (DMFS) (92.9% vs 92.1%, P = 0.901) to 2DCRT. In the propensity-matched cohort of 604 patients, no significant survival differences were observed between the two arms (5-year OS 90.9% vs 90.5%, P = 0.655; LRFS 92.5% vs 92.4%, P = 0.866; DMFS 92.5% vs 92.9%, P = 0.384). In multivariate analysis, IMRT did not significantly lower the risk of death, locoregional relapse or distant metastasis, irrespective of tumor stage. Methods Overall, 1198 patients who underwent IMRT (316 patients) or 2DCRT (882 patients) without any chemotherapy was retrospectively analyzed. Patients in both arms were matched at equal ratio using propensity-score matching method. OS, LRFS and DMFS were assessed with Kaplan-Meier method, log-rank test and Cox regression. Conclusions In this propensity-matched study, IMRT showed no survival advantage over 2DCRT alone in nasopharyngeal carcinoma. PMID:27058901

  6. Modeling the Risk of Secondary Malignancies after Radiotherapy

    PubMed Central

    Schneider, Uwe

    2011-01-01

    In developed countries, more than half of all cancer patients receive radiotherapy at some stage in the management of their disease. However, a radiation-induced secondary malignancy can be the price of success if the primary cancer is cured or at least controlled. Therefore, there is increasing concern regarding radiation-related second cancer risks in long-term radiotherapy survivors and a corresponding need to be able to predict cancer risks at high radiation doses. Of particular interest are second cancer risk estimates for new radiation treatment modalities such as intensity modulated radiotherapy, intensity modulated arc-therapy, proton and heavy ion radiotherapy. The long term risks from such modern radiotherapy treatment techniques have not yet been determined and are unlikely to become apparent for many years, due to the long latency time for solid tumor induction. Most information on the dose-response of radiation-induced cancer is derived from data on the A-bomb survivors who were exposed to γ-rays and neutrons. Since, for radiation protection purposes, the dose span of main interest is between zero and one Gy, the analysis of the A-bomb survivors is usually focused on this range. With increasing cure rates, estimates of cancer risk for doses larger than one Gy are becoming more important for radiotherapy patients. Therefore in this review, emphasis was placed on doses relevant for radiotherapy with respect to radiation induced solid cancer. Simple radiation protection models should be used only with extreme care for risk estimates in radiotherapy, since they are developed exclusively for low dose. When applied to scatter radiation, such models can predict only a fraction of observed second malignancies. Better semi-empirical models include the effect of dose fractionation and represent the dose-response relationships more accurately. The involved uncertainties are still huge for most of the organs and tissues. A major reason for this is that the

  7. Improved outcome of nasopharyngeal carcinoma treated with conventional radiotherapy

    SciTech Connect

    Palazzi, Mauro . E-mail: mauro.palazzi@istitutotumori.mi.it; Guzzo, Marco; Tomatis, Stefano Ph.D.; Cerrotta, Annamaria; Potepan, Paolo; Quattrone, Pasquale; Cantu, Giulio

    2004-12-01

    Purpose: To describe the outcome of patients with nonmetastatic nasopharyngeal carcinoma (NPC) treated with conventional radiotherapy at a single institution. Methods and materials: From 1990 to 1999, 171 consecutive patients with NPC were treated with conventional (two-dimensional) radiotherapy. Tumor histology was undifferentiated in 82% of cases. Tumor-node-metastasis Stage (American Joint Committee on Cancer/International Union Against Cancer 1997 system) was I in 6%, II in 36%, III in 22%, and IV in 36% of patients. Mean total radiation dose was 68.4 Gy. Chemotherapy was given to 62% of the patients. The median follow-up for surviving patients was 6.3 years (range, 3.1-13.1 years). Results: The 5-year overall survival, disease-specific survival, and disease-free survival rates were 72%, 74%, and 62%, respectively. The 5-year local, regional, and distant control rates were 84%, 80%, and 83% respectively. Late effects of radiotherapy were prospectively recorded in 100 patients surviving without relapse; 44% of these patients had Grade 3 xerostomia, 33% had Grade 3 dental damage, and 11% had Grade 3 hearing loss. Conclusions: This analysis shows an improved outcome for patients treated from 1990 to 1999 compared with earlier retrospective series, despite the use of two-dimensional radiotherapy. Late toxicity, however, was substantial with conventional radiotherapy.

  8. [The need for a paradigm shift in radiotherapy].

    PubMed

    Mayer, Árpád; Katona, Csilla; Farkas, Róbert; Póti, Zsuzsa

    2015-11-01

    The status and indications of radiotherapy have significantly changed in the past decade because novel techniques, radiobiological research and major advances in informatics have made better local control possible. Using supplemented marking of the target volume with computer tomography based other image-making methods adapted made it possible to define the tumor and intact surrounding tissues more precisely. With novel radiotherapy techniques the dosage of the homogenity and the covering in the target volume can be raised optimally, especially with intensity modulated arc radiotherapy (volumetric modulated arc therapy) without causing radiation injury or damage to intact surrounding tissues. Furthermore, with novel techniques and target volume marking, new indications have appeared in clinical practice and besides stereotactic radiotherapy for intracranial metastases, the extracranial so-called oligometastic conditions can be maintained close to a curative state (or in remission) for many years. Among these, perhaps the most striking is the stereotactic radiotherapy treatment of liver, lung and spinal cord metastases in one or more fractions, for which the indispensable condition is the image or respiratory guided technique.

  9. Combination chemotherapy and radiotherapy in non-Hodgkin's lymphomata.

    PubMed Central

    Bonadonna, G.; De Lena, M.; Lattuada, A.; Milani, F.; Monfardini, S.; Beretta, G.

    1975-01-01

    The results obtained with intensive chemotherapy and intensive chemotherapy plus radiotherapy in non-Hodgkin's lymphomata are reported. A quintuple drug regimen (mechloretamine, adriamycin, bleomycin, vincristine and prednisone) in histiocytic lymphomata (Stage III and IV) yielded complete remissions in 53% and complete plus partial remissions in 77%. These figures were 44% and 64% respectively in lymphocytic lymphoma. In Stage III complete responders after combination chemotherapy were subsequently irradiated (involved field irradiation). The median duration of complete remission after completion of radiotherapy was 9-5 months in histiocytic and 12-0 months in lymphocytic lymphomata. At 2 years actuarial survival in Stage III and IV was better in patients with the lymphocytic type and with nodular pattern than with histiocytic and diffuse patterns. A more recent trial compares, in Stage IV patients, cyclophosphamide, vincristine and prednisone (CVP) versus adriamycin, bleomycin and prednisone (ABP). Although the number of evaluable patients is still limited, there appears to be no difference in the response rate between CVP and ABP. In Stages I and II, 6 cycles of CVP were given as adjuvant treatment after radiotherapy. At the present moment, there is no statistical difference in the relapse rate between the group of patients treated with radiotherapy alone and that with radiotherapy plus CVP. PMID:52367

  10. Low-dose prophylactic craniospinal radiotherapy for intracranial germinoma

    SciTech Connect

    Schoenfeld, Gordon O.; Amdur, Robert J. . E-mail: amdurrj@ufl.edu; Schmalfuss, Ilona M.; Morris, Christopher G.; Keole, Sameer R.; Mendenhall, William M.; Marcus, Robert B.

    2006-06-01

    Purpose: To report outcomes of patients with localized intracranial germinoma treated with low-dose craniospinal irradiation (CSI) followed by a boost to the ventricular system and primary site. Methods and Materials: Thirty-one patients had pathologically confirmed intracranial germinoma and no spine metastases. Low-dose CSI was administered in 29 patients: usually 21 Gy of CSI, 9.0 Gy of ventricular boost, and a 19.5-Gy tumor boost, all at 1.5 Gy per fraction. Our neuroradiologist recorded three-dimensional tumor size on magnetic resonance images before, during, and after radiotherapy. Results: With a median follow-up of 7.0 years, 29 of 31 patients (94%) are disease free. One failure had nongerminomatous histology; the initial diagnosis was a sampling error. Of 3 patients who did not receive CSI, 1 died. No patient developed myelopathy, visual deficits, dementia, or skeletal growth problems. In locally controlled patients, tumor response according to magnetic resonance scan was nearly complete within 6 months after radiotherapy. Conclusions: Radiotherapy alone with low-dose prophylactic CSI cures almost all patients with localized intracranial germinoma. Complications are rare when the daily dose of radiotherapy is limited to 1.5 Gy and the total CSI dose to 21 Gy. Patients without a near-complete response to radiotherapy should undergo resection to rule out a nongerminomatous element.

  11. [Role of 18FDG-PET/CT in the management and gross tumor volume definition for radiotherapy of head and neck cancer; single institution experiences based on long-term follow-up].

    PubMed

    Hideghéty, Katalin; Cserháti, Adrienne; Besenyi, Zsuzsanna; Zag, Levente; Gaál, Szilvia; Együd, Zsófia; Mózes, Petra; Szántó, Erika; Csenki, Melinda; Rusz, Orsolya; Varga, Zoltán; Dobi, Ágnes; Maráz, Anikó; Pávics, László; Lengyel, Zsolt

    2015-06-01

    The purpose of our work is evaluation of the impact of 18FDG-PET/CT on the complex management of locoregionally advanced (T3-4N1-3) head and neck squamous cell cancer (LAHNSC), and on the target definition for 3D conformal (3DCRT) and intensity-modulated radiotherapy (IMRT). 18FDG-PET/CT were performed on 185 patients with LAHNSC prior to radiotherapy/chemoradiation in the treatment position between 2006 and 2011. Prior to it 91 patients received induction chemotherapy (in 20 cases of these, baseline PET/CT was also available). The independently delineated CT-based gross tumor volume (GTVct) and PET/CT based ones (GTVpet) were compared. Impact of PET/CT on the treatment strategy, on tumor response evaluation to ICT, on GTV definition furthermore on overall and disease-specific survival (OS, DSS) was analysed. PET/CT revealed 10 head and neck, 2 lung cancers for 15 patients with carcinoma of unknown primary (CUP) while 3 remained unknown. Second tumors were detected in 8 (4.4%), distant metastasis in 15 (8.2%) cases. The difference between GTVct and GTVpet was significant (p=0.001). In 16 patients (14%) the GTVpet were larger than GTVct due to multifocal manifestations in the laryngo-pharyngeal regions (4 cases) or lymph node metastases (12 cases). In the majority of the cases (82 pts, 72%) PET/CT-based conturing resulted in remarkable decrease in the volume (15-20%: 4 cases, 20-50%: 46 cases, >50%: 32 cases). On the basis of the initial and post-ICT PET/CT comparison in 15/20 patients more than 50% volume reduction and in 6/20 cases complete response were achieved. After an average of 6.4 years of follow-up the OS (median: 18.3±2.6 months) and DSS (median: 25.0±4.0 months) exhibited close correlation (p=0.0001) to the GTVpet. In cases with GTVpet <10 cm3 prior to RT, DSS did not reach the median, the mean is 82.1±6.1 months, while in cases with GTVpet 10-40 cm3 the median of the DSS was 28.8±4.9 months (HR = 3.57; 95% CI: 1.5-8.3), and in those with GTVpet >40

  12. Optimization approaches for planning external beam radiotherapy

    NASA Astrophysics Data System (ADS)

    Gozbasi, Halil Ozan

    Cancer begins when cells grow out of control as a result of damage to their DNA. These abnormal cells can invade healthy tissue and form tumors in various parts of the body. Chemotherapy, immunotherapy, surgery and radiotherapy are the most common treatment methods for cancer. According to American Cancer Society about half of the cancer patients receive a form of radiation therapy at some stage. External beam radiotherapy is delivered from outside the body and aimed at cancer cells to damage their DNA making them unable to divide and reproduce. The beams travel through the body and may damage nearby healthy tissue unless carefully planned. Therefore, the goal of treatment plan optimization is to find the best system parameters to deliver sufficient dose to target structures while avoiding damage to healthy tissue. This thesis investigates optimization approaches for two external beam radiation therapy techniques: Intensity-Modulated Radiation Therapy (IMRT) and Volumetric-Modulated Arc Therapy (VMAT). We develop automated treatment planning technology for IMRT that produces several high-quality treatment plans satisfying provided clinical requirements in a single invocation and without human guidance. A novel bi-criteria scoring based beam selection algorithm is part of the planning system and produces better plans compared to those produced using a well-known scoring-based algorithm. Our algorithm is very efficient and finds the beam configuration at least ten times faster than an exact integer programming approach. Solution times range from 2 minutes to 15 minutes which is clinically acceptable. With certain cancers, especially lung cancer, a patient's anatomy changes during treatment. These anatomical changes need to be considered in treatment planning. Fortunately, recent advances in imaging technology can provide multiple images of the treatment region taken at different points of the breathing cycle, and deformable image registration algorithms can

  13. Treatment planning system and dose delivery accuracy in extracranial stereotactic radiotherapy using Elekta body frame

    NASA Astrophysics Data System (ADS)

    Dawod, Tamer; Bremer, Michael; Karstens, Johann H.; Werner, Martin

    2010-01-01

    The purpose of this study was to measure the photon beam transmission through the Elekta Stereotactic Body Frame (ESBF) and treatment couch, to determine the dose calculations accuracy of the MasterPlan Treatment Planning System (TPS) using Pencil Beam (PBA) and Collapsed Cone (CCA) algorithms during the use of Elekta Stereotactic Body Frame (ESBF), and to demonstrate a simple calculation method to put this transmission into account during the treatment planning dose calculations. The dose was measured at the center of an in-house custom-built inhomogeneous PMMA thorax phantom with and without ‘the frame + treatment couch’. The phantom was CT-imaged inside the ESBF and planned with multiple 3D-CRT fields using PBA and CCA for photon beams of energies 6 MV and 10 MV. There were two treatment plans for dose calculations. In the first plan, the ‘frame + couch’ were included in the body contour and, therefore, included in the TPS dose calculations. In the second plan, the ‘frame + couch’ were not included in the body contour and, therefore, not included in the calculations. Transmission of the ‘frame + couch’ was determined by the ratio of the dose measurements with the ‘frame + couch’ to the measurements without them. To validate the accuracy of the calculation model, plans with and without the ‘frame + couch’ surrounding the phantoms were compared with their corresponding measurements. The transmission of the ‘frame + couch’ varies from 90.23-97.54% depending on the energy, field size, the angle of the beams and whether the beams also intercept them. The validation accuracy of the Pencil Beam (PBA) and Collapsed Cone (CCA) algorithms were within 5.33% and 4.04% respectively for the individual measurements for all gantry angles under this study. The results showed that both PBA and CCA algorithms can calculate the dose to the target within 4.25% and 1.95% of the average measured value. The attenuation caused by the ESBF and couch must be

  14. Radiotherapy issues in elderly breast cancer patients.

    PubMed

    Kunkler, Ian

    2012-12-01

    Breast cancer in the elderly is a rising health care challenge. Under-treatment is common. While the proportion of older patients receiving adjuvant radiotherapy (RT) is rising, the proportion undergoing breast-conserving surgery without irradiation has also risen. The evidence base for loco-regional treatment is limited, reflecting the historical exclusion of older patients from randomised trials. The 2011 Oxford overview shows that the risk of first recurrence is halved in all age groups by adjuvant RT after breast-conserving surgery, although the absolute benefit in older 'low-risk' patients is small. There is level 1 evidence that a breast boost after breast-conserving surgery and whole-breast irradiation reduces local recurrence in older as in younger women, although in the former the absolute reduction is modest. Partial breast irradiation (external beam or intraoperative or postoperative brachytherapy) is potentially an attractive option for older patients, but the evidence base is insufficient to recommend it routinely. Similarly, shortened (hypofractionated) dose fraction schedules may be more convenient for older patients and are supported by level 1 evidence. There remains uncertainty about whether there is a subgroup of older low-risk patients in whom postoperative RT can be omitted after breast-conserving surgery. Biomarkers of 'low risk' are needed to refine the selection of patients for the omission of adjuvant RT. The role of postmastectomy irradiation is well established for 'high-risk' patients but uncertain in the intermediate-risk category of patients with 1-3 involved axillary nodes or node-negative patients with other risk factors where its role is investigational.

  15. Predicting radiotherapy outcomes using statistical learning techniques.

    PubMed

    El Naqa, Issam; Bradley, Jeffrey D; Lindsay, Patricia E; Hope, Andrew J; Deasy, Joseph O

    2009-09-21

    Radiotherapy outcomes are determined by complex interactions between treatment, anatomical and patient-related variables. A common obstacle to building maximally predictive outcome models for clinical practice is the failure to capture potential complexity of heterogeneous variable interactions and applicability beyond institutional data. We describe a statistical learning methodology that can automatically screen for nonlinear relations among prognostic variables and generalize to unseen data before. In this work, several types of linear and nonlinear kernels to generate interaction terms and approximate the treatment-response function are evaluated. Examples of institutional datasets of esophagitis, pneumonitis and xerostomia endpoints were used. Furthermore, an independent RTOG dataset was used for 'generalizabilty' validation. We formulated the discrimination between risk groups as a supervised learning problem. The distribution of patient groups was initially analyzed using principle components analysis (PCA) to uncover potential nonlinear behavior. The performance of the different methods was evaluated using bivariate correlations and actuarial analysis. Over-fitting was controlled via cross-validation resampling. Our results suggest that a modified support vector machine (SVM) kernel method provided superior performance on leave-one-out testing compared to logistic regression and neural networks in cases where the data exhibited nonlinear behavior on PCA. For instance, in prediction of esophagitis and pneumonitis endpoints, which exhibited nonlinear behavior on PCA, the method provided 21% and 60% improvements, respectively. Furthermore, evaluation on the independent pneumonitis RTOG dataset demonstrated good generalizabilty beyond institutional data in contrast with other models. This indicates that the prediction of treatment response can be improved by utilizing nonlinear kernel methods for discovering important nonlinear interactions among model

  16. Carbon Ion Radiotherapy for Unresectable Retroperitoneal Sarcomas

    SciTech Connect

    Serizawa, Itsuko; Kagei, Kenji; Kamada, Tadashi; Imai, Reiko; Sugahara, Shinji; Okada, Tohru; Tsuji, Hiroshi; Ito, Hisao; Tsujii, Hirohiko

    2009-11-15

    Purpose: To evaluate the applicability of carbon ion radiotherapy (CIRT) for unresectable retroperitoneal sarcomas with regard to normal tissue morbidity and local tumor control. Methods and Materials: From May 1997 to February 2006, 24 patients (17 male and 7 female) with unresectable retroperitoneal sarcoma received CIRT. Age ranged from 16 to 77 years (median, 48.6 years). Of the patients, 16 had primary disease and 8 recurrent disease. Histologic diagnoses were as follows: malignant fibrous histiocytoma in 6, liposarcoma in 3, malignant peripheral nerve sheath tumor in 3, Ewing/primitive neuroectodermal tumor (PNET) in 2, and miscellaneous in 10 patients. The histologic grades were as follows: Grade 3 in 15, Grade 2-3 in 2, Grade 2 in 3, and unknown in 4. Clinical target volumes ranged between 57 cm{sup 3} and 1,194 cm{sup 3} (median 525 cm{sup 3}). The delivered carbon ion dose ranged from 52.8 to 73.6 GyE in 16 fixed fractions over 4 weeks. Results: The median follow-up was 36 months (range, 6-143 months). The overall survival rates at 2 and 5 years were 75% and 50%, respectively. The local control rates at 2 and 5 years were 77% and 69%. No complications of the gastrointestinal tract were encountered. No other toxicity greater than Grade 2 was observed. Conclusions: Use of CIRT is suggested to be effective and safe for retroperitoneal sarcomas. The results obtained with CIRT were a good overall survival rate and local control, notwithstanding the fact that most patients were not eligible for surgical resection and had high-grade sarcomas.

  17. Spinal Cord Tolerance for Stereotactic Body Radiotherapy

    SciTech Connect

    Sahgal, Arjun; Ma Lijun; Gibbs, Iris; Gerszten, Peter C.; Ryu, Sam; Soltys, Scott; Weinberg, Vivian; Wong Shun; Chang, Eric; Fowler, Jack; Larson, David A.

    2010-06-01

    Purpose: Dosimetric data are reported for five cases of radiation-induced myelopathy after stereotactic body radiotherapy (SBRT) to spinal tumors. Analysis per the biologically effective dose (BED) model was performed. Methods and Materials: Five patients with radiation myelopathy were compared to a subset of 19 patients with no radiation myelopathy post-SBRT. In all patients, the thecal sac was contoured to represent the spinal cord, and doses to the maximum point, 0.1-, 1-, 2-, and 5-cc volumes, were analyzed. The mean normalized 2-Gy-equivalent BEDs (nBEDs), calculated using an alpha/beta value of 2 for late toxicity with units Gy 2/2, were compared using the t test and analysis of variance test. Results: Radiation myelopathy was observed at the maximum point with doses of 25.6 Gy in two fractions, 30.9 Gy in three fractions, and 14.8, 13.1, and 10.6 Gy in one fraction. Overall, there was a significant interaction between patient subsets and volume based on the nBED (p = 0.0003). Given individual volumes, a significant difference was observed for the mean maximum point nBED (p = 0.01). Conclusions: The maximum point dose should be respected for spine SBRT. For single-fraction SBRT 10 Gy to a maximum point is safe, and up to five fractions an nBED of 30 to 35 Gy 2/2 to the thecal sac also poses a low risk of radiation myelopathy.

  18. Volumetric Modulated Arc Radiotherapy for Vestibular Schwannomas

    SciTech Connect

    Lagerwaard, Frank J. Meijer, Otto W.M.; Hoorn, Elles A.P. van der; Verbakel, Wilko; Slotman, Ben J.; Senan, Suresh

    2009-06-01

    Purpose: To evaluate volumetric modulated arc radiotherapy (RapidArc [RA]), a novel approach allowing for rapid treatment delivery, for the treatment of vestibular schwannoma (VS). Methods and Materials: The RA plans were generated for a small (0.5 cm{sup 3}), intermediate (2.8 cm{sup 3}), and large (14.8 cm{sup 3}) VS. The prescription dose was 12.5 Gy to the encompassing 80% isodose. The RA plans were compared with conventional radiosurgery plans using both a single dynamic conformal arc (1DCA) and five noncoplanar dynamic conformal arcs (5DCA). Conformity indices (CI) and dose-volume histograms of critical organs were compared. The RA plan for the medium-sized VS was measured in a phantom using Gafchromic EBT films and compared with calculated dose distributions. Results: The RA planning was completed within 30 min in all cases, and calculated treatment delivery time (after patient setup) was 5 min vs. 20 min for 5DCA. A superior CI was achieved with RA, with a substantial decrease in low-dose irradiation of the normal brain achieved relative to 5DCA plans. Maximum doses to critical organs were similar for RA and 5DCA but were higher for 1DCA. Film measurements showed the differences between calculated and measured doses to be smaller than 1.5% in the high-dose area and smaller than 3% in the low-dose area. Conclusion: The RA plans consistently achieved a higher CI and decrease in areas of low-dose irradiation. This, together with shorter treatment delivery times, has led to RA replacing our conventional five-arc radiosurgery technique for VS.

  19. Predicting radiotherapy outcomes using statistical learning techniques

    NASA Astrophysics Data System (ADS)

    El Naqa, Issam; Bradley, Jeffrey D.; Lindsay, Patricia E.; Hope, Andrew J.; Deasy, Joseph O.

    2009-09-01

    Radiotherapy outcomes are determined by complex interactions between treatment, anatomical and patient-related variables. A common obstacle to building maximally predictive outcome models for clinical practice is the failure to capture potential complexity of heterogeneous variable interactions and applicability beyond institutional data. We describe a statistical learning methodology that can automatically screen for nonlinear relations among prognostic variables and generalize to unseen data before. In this work, several types of linear and nonlinear kernels to generate interaction terms and approximate the treatment-response function are evaluated. Examples of institutional datasets of esophagitis, pneumonitis and xerostomia endpoints were used. Furthermore, an independent RTOG dataset was used for 'generalizabilty' validation. We formulated the discrimination between risk groups as a supervised learning problem. The distribution of patient groups was initially analyzed using principle components analysis (PCA) to uncover potential nonlinear behavior. The performance of the different methods was evaluated using bivariate correlations and actuarial analysis. Over-fitting was controlled via cross-validation resampling. Our results suggest that a modified support vector machine (SVM) kernel method provided superior performance on leave-one-out testing compared to logistic regression and neural networks in cases where the data exhibited nonlinear behavior on PCA. For instance, in prediction of esophagitis and pneumonitis endpoints, which exhibited nonlinear behavior on PCA, the method provided 21% and 60% improvements, respectively. Furthermore, evaluation on the independent pneumonitis RTOG dataset demonstrated good generalizabilty beyond institutional data in contrast with other models. This indicates that the prediction of treatment response can be improved by utilizing nonlinear kernel methods for discovering important nonlinear interactions among model

  20. Carbon ion radiotherapy of skull base chondrosarcomas

    SciTech Connect

    Schulz-Ertner, Daniela . E-mail: Daniela.Ertner@med.uni-heidelberg.de; Nikoghosyan, Anna; Hof, Holger; Didinger, Bernd; Combs, Stephanie E.; Jaekel, Oliver; Karger, Christian P.; Edler, Lutz; Debus, Juergen

    2007-01-01

    Purpose: To evaluate the effectiveness and toxicity of carbon ion radiotherapy in chondrosarcomas of the skull base. Patients and Methods: Between November 1998 and September 2005, 54 patients with low-grade and intermediate-grade chondrosarcomas of the skull base have been treated with carbon ion radiation therapy (RT) using the raster scan technique at the Gesellschaft fuer Schwerionenforschung in Darmstadt, Germany. All patients had gross residual tumors after surgery. Median total dose was 60 CGE (weekly fractionation 7 x 3.0 CGE). All patients were followed prospectively in regular intervals after treatment. Local control and overall survival rates were calculated using the Kaplan-Meier method. Toxicity was assessed according to the Common Terminology Criteria (CTCAE v.3.0) and Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) score. Results: Median follow-up was 33 months (range, 3-84 months). Only 2 patients developed local recurrences. The actuarial local control rates were 96.2% and 89.8% at 3 and 4 years; overall survival was 98.2%at 5 years. Only 1 patient developed a mucositis CTCAE Grade 3; the remaining patients did not develop any acute toxicities >CTCAE Grade 2. Five patients developed minor late toxicities (RTOG/EORTC Grades 1-2), including bilateral cataract (n = 1), sensory hearing loss (n = 1), a reduction of growth hormone (n = 1), and asymptomatic radiation-induced white matter changes of the adjacent temporal lobe (n = 2). Grade 3 late toxicity occurred in 1 patient (1.9%) only. Conclusions: Carbon ion RT is an effective treatment for low- and intermediate-grade chondrosarcomas of the skull base offering high local control rates with low toxicity.

  1. Stereotactic Body Radiotherapy for Primary Hepatocellular Carcinoma

    SciTech Connect

    Andolino, David L.; Johnson, Cynthia S.; Maluccio, Mary; Kwo, Paul; Tector, A. Joseph; Zook, Jennifer; Johnstone, Peter A.S.; Cardenes, Higinia R.

    2011-11-15

    Purpose: To evaluate the safety and efficacy of stereotactic body radiotherapy (SBRT) for the treatment of primary hepatocellular carcinoma (HCC). Methods and Materials: From 2005 to 2009, 60 patients with liver-confined HCC were treated with SBRT at the Indiana University Simon Cancer Center: 36 Child-Turcotte-Pugh (CTP) Class A and 24 CTP Class B. The median number of fractions, dose per fraction, and total dose, was 3, 14 Gy, and 44 Gy, respectively, for those with CTP Class A cirrhosis and 5, 8 Gy, and 40 Gy, respectively, for those with CTP Class B. Treatment was delivered via 6 to 12 beams and in nearly all cases was prescribed to the 80% isodose line. The records of all patients were reviewed, and treatment response was scored according to Response Evaluation Criteria in Solid Tumors v1.1. Toxicity was graded according to the Common Terminology Criteria for Adverse Events v4.0. Local control (LC), time to progression (TTP), progression-free survival (PFS), and overall survival (OS) were calculated according to the method of Kaplan and Meier. Results: The median follow-up time was 27 months, and the median tumor diameter was 3.2 cm. The 2-year LC, PFS, and OS were 90%, 48%, and 67%, respectively, with median TTP of 47.8 months. Subsequently, 23 patients underwent transplant, with a median time to transplant of 7 months. There were no {>=}Grade 3 nonhematologic toxicities. Thirteen percent of patients experienced an increase in hematologic/hepatic dysfunction greater than 1 grade, and 20% experienced progression in CTP class within 3 months of treatment. Conclusions: SBRT is a safe, effective, noninvasive option for patients with HCC {<=}6 cm. As such, SBRT should be considered when bridging to transplant or as definitive therapy for those ineligible for transplant.

  2. Carotid artery disease after head and neck radiotherapy.

    PubMed

    Thalhammer, Christoph; Husmann, Marc; Glanzmann, Christoph; Studer, Gabriela; Amann-Vesti, Beatrice R

    2015-01-01

    Radiation induced atherosclerosis of the carotid artery is a clinically relevant late complication after head and neck radiotherapy. Improved long-term survival after multimodality therapy in neck malignancies result in an increased risk of carotid artery disease in patients after radiotherapy (RT). This review focuses on the current knowledge of occlusive carotid disease after head and neck radiotherapy and highlights the exceeding morphologic post-radiation vessel wall pathologies. More severe and extensive carotid artery atherosclerosis with plaque in all segments including the common carotid artery is a frequent finding after RT. Therefore, colour coded duplex ultrasound surveillance in patients after head and neck RT is recommended. Some histopathological studies indicate differences to “classical” atherosclerosis, and pathogenesis of chronic radiation vasculopathy is still under discussion.

  3. Could Radiotherapy Effectiveness Be Enhanced by Electromagnetic Field Treatment?

    PubMed Central

    Francisco, Artacho-Cordón; del Mar, Salinas-Asensio María; Irene, Calvente; Sandra, Ríos-Arrabal; Josefa, León; Elisa, Román-Marinetto; Nicolás, Olea; Isabel, Núñez María

    2013-01-01

    One of the main goals in radiobiology research is to enhance radiotherapy effectiveness without provoking any increase in toxicity. In this context, it has been proposed that electromagnetic fields (EMFs), known to be modulators of proliferation rate, enhancers of apoptosis and inductors of genotoxicity, might control tumor recruitment and, thus, provide therapeutic benefits. Scientific evidence shows that the effects of ionizing radiation on cellular compartments and functions are strengthened by EMF. Although little is known about the potential role of EMFs in radiotherapy (RT), the radiosensitizing effect of EMFs described in the literature could support their use to improve radiation effectiveness. Thus, we hypothesized that EMF exposure might enhance the ionizing radiation effect on tumor cells, improving the effects of RT. The aim of this paper is to review reports of the effects of EMFs in biological systems and their potential therapeutic benefits in radiotherapy. PMID:23867611

  4. Dose factor entry and display tool for BNCT radiotherapy

    DOEpatents

    Wessol, Daniel E.; Wheeler, Floyd J.; Cook, Jeremy L.

    1999-01-01

    A system for use in Boron Neutron Capture Therapy (BNCT) radiotherapy planning where a biological distribution is calculated using a combination of conversion factors and a previously calculated physical distribution. Conversion factors are presented in a graphical spreadsheet so that a planner can easily view and modify the conversion factors. For radiotherapy in multi-component modalities, such as Fast-Neutron and BNCT, it is necessary to combine each conversion factor component to form an effective dose which is used in radiotherapy planning and evaluation. The Dose Factor Entry and Display System is designed to facilitate planner entry of appropriate conversion factors in a straightforward manner for each component. The effective isodose is then immediately computed and displayed over the appropriate background (e.g. digitized image).

  5. Role of hypofractionated radiotherapy in breast locoregional radiation.

    PubMed

    Caudrelier, J-M; Truong, P T

    2015-06-01

    Long-term results of randomised trials have confirmed the safety and efficacy of hypofractionated radiotherapy using approximately 2.6 Gy per fraction to lower total doses of 40-42.6 Gy delivered over 3 weeks, for postoperative treatment of early breast cancer. In these trials, hypofractionated radiotherapy was predominantly used for breast only treatment, while there are fewer trials that specifically examined hypofractionated radiotherapy to the breast plus regional nodes. Hypofractionated locoregional radiation is considered a standard of care in the United Kingdom and in some parts of Canada. We aim to review the radiobiology and normal tissue effects of hypofractionated locoregional radiation and to summarize available published clinical experiences using this treatment strategy as adjuvant therapy after breast conserving surgery or mastectomy for women with early breast cancer.

  6. Endometrial adenocarcinoma, adjuvant radiotherapy tailored to prognostic factors.

    PubMed

    Meerwaldt, J H; Hoekstra, C J; van Putten, W L; Tjokrowardojo, A J; Koper, P C

    1990-02-01

    The optimal adjuvant radiotherapy for surgically treated endometrial cancer has not yet been defined. We report on 389 patients treated between 1970 and 1985 with adjuvant radiotherapy. The treatment was tailored to the known prognostic factors: myometrial invasion and grade of differentiation of the tumor. Ten-year overall survival was 67%, 10-year relapse-free survival 77%; 23% relapse, of which 21% distant and 6% locoregional relapse. In a multivariate analysis, stage (pT), grade, and myometrial invasion were prognostic factors. The number of locoregional failures was very small (n = 23). This small number, the fact that radiation treatment was tailored to prognostic factors, and the absence of a nontreated control group precluded an analysis of the effect of the adjuvant irradiation. Large randomized studies with a control (no treatment) arm should be performed to determine the value of adjuvant radiotherapy.

  7. Role of additional radiotherapy in advanced stages of Hodgkin's disease.

    PubMed

    Meerwaldt, J H; Coleman, C N; Fischer, R I; Lister, T A; Diehl, V

    1992-09-01

    Although radiotherapy is widely used as additional treatment following chemotherapy, its precise role has never been clearly proven. Relapses tend to occur in previously involved bulky sites. Non-randomized studies may suggest a positive effect of the addition of radiotherapy. This effect however, might also be caused by selection. Randomized studies have not resulted in a survival advantage for the patients treated with additional radiotherapy compared to no further treatment or additional chemotherapy. The SWOG study 7808 suggest a 20% benefit in remission duration for the nodular sclerosis histology subgroup. Definitive conclusions have to wait for more mature results of randomized studies including the ongoing EORTC study and the possibility to perform an overview of all studies.

  8. Radiotherapy-induced skin reactions: assessment and management.

    PubMed

    Glover, Deborah; Harmer, Victoria

    Radiotherapy, the use of high-energy rays to either kill cancer cells or treat some benign tumours, is undoubtedly a positive intervention. However, as the primary mode of action in radiotherapy treatment is the killing of cells to prevent replication, other non-cancerous cells may be affected. For example, up to 85% of patients will experience some form of skin reaction, which will range from local erythema to moist desquamation. Such reactions are not only distressing and painful for the patient, if severe enough, they may warrant a halt in treatment. This article outlines the aims and nature of radiotherapy, and then discusses the aetiology of skin reactions, risk factors for reaction, and assessment tools. Management interventions will also be shown, with emphasis on silicone dressings.

  9. The role of radiotherapy in multimodal treatment of pancreatic carcinoma

    PubMed Central

    2010-01-01

    Pancreatic ductal carcinoma is one of the most lethal malignancies, but in recent years a number of positive developments have occurred in the management of pancreatic carcinoma. This article aims to give an overview of the current knowledge regarding the role of radiotherapy in the treatment of pancreatic ductal adenocarcinoma (PDAC). The results of meta-analyses, phase III-studies, and phase II-studies using chemoradiotherapy and chemotherapy for resectable and non-resectable PDAC were reviewed. The use of radiotherapy is discussed in the neoadjuvant and adjuvant settings as well as in the locally advanced situation. Whenever possible, radiotherapy should be performed as simultaneous chemoradiotherapy. Patients with PDAC should be offered entry into clinical trials to identify optimal treatment results. PMID:20615227

  10. Cytogenetic, clinical, and cytologic characteristics of radiotherapy-related leukemias

    SciTech Connect

    Philip, P.; Pedersen-Bjergaard, J.

    1988-04-01

    From 1978 to 1985, we observed eight cases of acute nonlymphocytic leukemia or preleukemia, three cases of acute lymphoblastic leukemia, and three cases of chronic myeloid leukemia in patients previously treated exclusively with radiotherapy for other tumor types. The latent period from administration of radiotherapy to development of leukemia varied between 12 and 243 months. Clonal chromosome aberrations reported previously as characteristic of acute nonlymphocytic leukemia following therapy with alkylating agents were observed in three of the eight patients with acute nonlymphocytic leukemia (5q- and -7) and in two of the three patients with acute lymphoblastic leukemia (-7 and 12p-). All three patients with radiotherapy-related chronic myeloid leukemia presented a t(9;22)(q34;q11). The results suggest that cytogenetic characteristics may reflect the etiology in radiation-induced acute leukemias, whereas radiation-related chronic myeloid leukemia does not seem to differ chromosomally from de novo cases of the disease.

  11. Radiotherapy for extramammary Paget disease of the anogenital region.

    PubMed

    Dilmé-Carreras, Elisabet; Iglesias-Sancho, Maribel; Márquez-Balbás, Gemma; Sola-Ortigosa, Joaquín; Umbert-Millet, Pablo

    2011-07-01

    Extramammary Paget disease is a rare condition that most commonly affects the anogenital region in the elderly. The treatment of choice has been surgical excision of the affected area with adequate depth and lateral margins, criteria that cannot always be fulfilled, especially when the vulva, anal canal, or penis are involved. More recently radiotherapy has been suggested as a suitable treatment when surgical excision or other modalities are not appropriate. We report a case of anogenital extramammary Paget disease and the clinical response to treatment with radiotherapy. The aim of this article is to review relevant aspects of radiotherapy as a first-choice curative treatment in specific situations of anogenital extramammary Paget disease in situ.

  12. Imaging practices and radiation doses from imaging in radiotherapy.

    PubMed

    Siiskonen, Teemu; Kaijaluoto, Sampsa; Florea, Tudor

    2017-03-25

    Modern radiotherapy treatments require frequent imaging for accurate patient positioning relative to the therapeutic radiation beam. Imaging practices in five Finnish radiotherapy clinics were assessed and discussed from the patient dose optimization point of view. The results show that imaging strategies are not jointly established and variations exist. The organ absorbed doses depend on imaging technique and imaging frequency. In particular, organ doses from the cone beam computed tomography can have very large variations (a factor of 10-50 in breast imaging and factor of 5 in prostate imaging). The cumulative imaging organ dose from the treatment can vary by a factor of ten or more for the same treatment, depending on the chosen technique and imaging frequency. Awareness and optimization of the imaging dose in image-guided radiotherapy should be strengthened.

  13. Radiotherapy-induced concomitant coronary artery stenosis and mitral valve disease.

    PubMed

    Akboga, Mehmet Kadri; Akyel, Ahmet; Sahinarslan, Asife; Cengel, Atiye

    2014-04-01

    Radiotherapy is extensively used in the treatment of Hodgkin's disease. One of its untoward effects is on heart. Coronary arteries and heart valves can be adversely affected from radiotherapy. However, co-existence of both conditions is very rare. In this report, we present a patient with Hodgkin's disease who developed both coronary artery stenosis and severe mitral valve regurgitation after radiotherapy.

  14. Randomized comparisons of radiotherapy and nitrosoureas for the treatment of malignant glioma after surgery

    SciTech Connect

    Walker, M.D.; Green, S.B.; Byar, D.P.

    1980-12-04

    Within three weeks of definitive surgical intervention, 467 patients with histologically proved malignant glioma were randomized to receive one of four treatment regimens: semustine (MeCCNU), radiotherapy, carmustine (BCNU) plus radiotherapy, or semustine plus radiotherapy. We analyzed the data for the total randomized population and for the 358 patients in whom the initial protocol specifications were met (the valid study group). Observed toxicity included acceptable skin reactions secondary to radiotherapy and reversible leukopenia and thrombocytopenia due to chemotherapy. Radiotherapy used alone or in combination with a nitrosourea significantly improved survival in comparison with semustine alone. The group receiving carmustine plus radiotherapy had the best survival, but the difference in survival between the groups receiving carmustine plus radiotherapy and semustine plus radiotherapy was not statistically significant. The combination of carmustine plus radiotherapy produced a modest benefit in long-term (18-month) survival as compared with radiotherapy alone, although the difference between survival curves was not significant at the 0.05 level. This study suggests that it is best to use radiotherapy in the post-surgical treatment of malignant glioma and to continue the search for an effective chemotherapeutic regimen to use in addition to radiotherapy.

  15. Patterns of care of radiotherapy in México

    PubMed Central

    Poitevin-Chacón, Adela; Hinojosa-Gómez, José

    2012-01-01

    Aim This survey is performed to learn about the structure of radiotherapy in México. Background Radiation oncology practice is increasing because of the higher incidence of cancer. There is no published data about radiotherapy in México. Materials and methods A questionnaire was sent to the 83 registered centers in the database of the Mexican regulatory agency. One out of the 32 states has no radiotherapy. 27 centers from 14 states provided their answers. Results 829 patients are treated annually with any radiotherapy modality in each center. Two centers have one cobalt machine, 7 have a cobalt and a linac and 10 have more than one linac. Five centers use 2D planning systems, 22 use 3D; 9, conventional simulators; 22, CT based simulation, and 1 center has no simulation. Most of the centers verify beams with films, electronic portal image devices and cone beam CTs are also used. Intensity modulated and image guided radiotherapy are performed in 5 states. Breast, prostate, cervix, lung, rectum and head and neck cancer are the six most common locations. There are 45 public and 38 private centers, 2 dedicated to children. Two gamma knife units, 5 Novalis systems, 1 tomotherapy and 2 cyberknife machines are working. All centers have at least one radiation oncologist, one physicist and one radiotherapist. Conclusions Definitive conclusions cannot be drawn from this limited feedback due to a low participation of centers. This survey about radiotherapy in Mexico shows the heterogeneity of equipment as well as medical and technical staff in the whole country. PMID:24416531

  16. Adjuvant radiotherapy for locally advanced upper tract urothelial carcinoma

    PubMed Central

    Huang, Yun-Ching; Chang, Ying-Hsu; Chiu, Kuo-Hsiung; Shindel, Alan W.; Lai, Chia-Hsuan

    2016-01-01

    There is relatively little literature on adjuvant radiotherapy after radical nephroureterectomy with bladder cuff excision (RNU) for patients with upper tract urothelial carcinoma (UTUC). This study was designed to determine the efficacy of adjuvant radiotherapy for patients with pT3N0M0 UTUC. We retrospectively reviewed 198 patients treated with RNU between December 2001 and January 2015. Postoperative radiotherapy was administered in 40 (20.2%) of patients. Patients who received radiotherapy were younger than those that did not (65.2 vs. 70.5 years, p = 0.023). With median follow up of 29.1 months, Kaplan-Meier analysis with the log-rank test demonstrated no significant differences between those omitting vs receiving adjuvant radiotherapy in regards to 2-year rates of overall survival (72.0% vs. 73.4%, p = 0.979), cancer-specific survival (73.2% vs. 75.3%, p = 0.844), and recurrence-free survival (61.2% vs. 66.3%, p = 0.742). However, in multivariable analysis with Cox regression, young age, absence of chronic kidney disease, negative lymphovascular invasion, negative surgical margin, and adjuvant chemotherapy were also associated with better cancer-specific survival. In conclusion, adjuvant radiotherapy did not offer any significant benefit in terms of overall, cancer-specific, and recurrence-free survivals in patients with pT3N0M0 UTUC after RNU. More effective systemic adjuvant chemotherapy is necessary to improve the outcome of these patients. PMID:27910890

  17. Mathematical Modeling of Cancer Immunotherapy and Its Synergy with Radiotherapy.

    PubMed

    Serre, Raphael; Benzekry, Sebastien; Padovani, Laetitia; Meille, Christophe; André, Nicolas; Ciccolini, Joseph; Barlesi, Fabrice; Muracciole, Xavier; Barbolosi, Dominique

    2016-09-01

    Combining radiotherapy with immune checkpoint blockade may offer considerable therapeutic impact if the immunosuppressive nature of the tumor microenvironment (TME) can be relieved. In this study, we used mathematical models, which can illustrate the potential synergism between immune checkpoint inhibitors and radiotherapy. A discrete-time pharmacodynamic model of the combination of radiotherapy with inhibitors of the PD1-PDL1 axis and/or the CTLA4 pathway is described. This mathematical framework describes how a growing tumor first elicits and then inhibits an antitumor immune response. This antitumor immune response is described by a primary and a secondary (or memory) response. The primary immune response appears first and is inhibited by the PD1-PDL1 axis, whereas the secondary immune response happens next and is inhibited by the CTLA4 pathway. The effects of irradiation are described by a modified version of the linear-quadratic model. This modeling offers an explanation for the reported biphasic relationship between the size of a tumor and its immunogenicity, as measured by the abscopal effect (an off-target immune response). Furthermore, it explains why discontinuing immunotherapy may result in either tumor recurrence or a durably sustained response. Finally, it describes how synchronizing immunotherapy and radiotherapy can produce synergies. The ability of the model to forecast pharmacodynamic endpoints was validated retrospectively by checking that it could describe data from experimental studies, which investigated the combination of radiotherapy with immune checkpoint inhibitors. In summary, a model such as this could be further used as a simulation tool to facilitate decision making about optimal scheduling of immunotherapy with radiotherapy and perhaps other types of anticancer therapies. Cancer Res; 76(17); 4931-40. ©2016 AACR.

  18. Unilateral Radiotherapy for the Treatment of Tonsil Cancer

    SciTech Connect

    Chronowski, Gregory M.; Garden, Adam S.; Morrison, William H.; Frank, Steven J.; Schwartz, David L.; Shah, Shalin J.; Beadle, Beth M.; Gunn, G. Brandon; Kupferman, Michael E.; Ang, Kian K.; Rosenthal, David I.

    2012-05-01

    Purpose: To assess, through a retrospective review, clinical outcomes of patients with squamous cell carcinoma of the tonsil treated at the M. D. Anderson Cancer Center with unilateral radiotherapy techniques that irradiate the involved tonsil region and ipsilateral neck only. Methods and Materials: Of 901 patients with newly diagnosed squamous cell carcinoma of the tonsil treated with radiotherapy at our institution, we identified 102 that were treated using unilateral radiotherapy techniques. All patients had their primary site of disease restricted to the tonsillar fossa or anterior pillar, with <1 cm involvement of the soft palate. Patients had TX (n = 17 patients), T1 (n = 52), or T2 (n = 33) disease, with Nx (n = 3), N0 (n = 33), N1 (n = 23), N2a (n = 21), or N2b (n = 22) neck disease. Results: Sixty-one patients (60%) underwent diagnostic tonsillectomy before radiotherapy. Twenty-seven patients (26%) underwent excision of a cervical lymph node or neck dissection before radiotherapy. Median follow-up for surviving patients was 38 months. Locoregional control at the primary site and ipsilateral neck was 100%. Two patients experienced contralateral nodal recurrence (2%). The 5-year overall survival and disease-free survival rates were 95% and 96%, respectively. The 5-year freedom from contralateral nodal recurrence rate was 96%. Nine patients required feeding tubes during therapy. Of the 2 patients with contralateral recurrence, 1 experienced an isolated neck recurrence and was salvaged with contralateral neck dissection only and remains alive and free of disease. The other patient presented with a contralateral base of tongue tumor and involved cervical lymph node, which may have represented a second primary tumor, and died of disease. Conclusions: Unilateral radiotherapy for patients with TX-T2, N0-N2b primary tonsil carcinoma results in high rates of disease control, with low rates of contralateral nodal failure and a low incidence of acute toxicity

  19. A new fixation aid for the radiotherapy of eye tumors

    SciTech Connect

    Buchgeister, Markus; Grisanti, Salvatore; Suesskind, Daniela; Bamberg, Michael; Paulsen, Frank

    2007-12-15

    A modified swim goggle holding a light spot as an optical guide for actively aligning the eye in a reproducible orientation has been constructed to perform radiotherapy of ocular tumors. This device is compatible with computed tomography (CT) and magnetic resonance imaging systems. Image fusion of these data sets yielded clinically acceptable results. The reproducibility of the eye's positioning is tested by repeated CT. The eye's alignment during radiotherapy is monitored by an infrared TV camera with individual markings of the eye's position on the TV-monitor screen. From 2003-2006, 50 patients were treated with this fixation aid by radiosurgery with good patient compliance.

  20. Genetics and genomics of radiotherapy toxicity: towards prediction

    PubMed Central

    2011-01-01

    Radiotherapy is involved in many curative treatments of cancer; millions of survivors live with the consequences of treatment, and toxicity in a minority limits the radiation doses that can be safely prescribed to the majority. Radiogenomics is the whole genome application of radiogenetics, which studies the influence of genetic variation on radiation response. Work in the area focuses on uncovering the underlying genetic causes of individual variation in sensitivity to radiation, which is important for effective, safe treatment. In this review, we highlight recent advances in radiotherapy and discuss results from four genome-wide studies of radiotoxicity. PMID:21861849

  1. The use of antioxidants in radiotherapy-induced skin toxicity.

    PubMed

    Amber, Kyle T; Shiman, Michael I; Badiavas, Evangelos V

    2014-01-01

    Radiation-induced skin damage is one of the most common complications of radiotherapy. In order to combat these side effects, patients often turn to alternative therapies, which often include antioxidants. Antioxidants such as those in the polyphenol chemical class, xanthine derivatives, tocepherol, sucralfate, and ascorbate have been studied for their use in either preventing or treating radiotherapy-induced skin damage. Apart from their known role as free radical scavengers, some of these antioxidants appear to alter cytokine release affecting cutaneous and systemic changes. We review the role of antioxidants in treating and preventing radiation-induced skin damage as well as the possible complications of using such therapy.

  2. A new fixation aid for the radiotherapy of eye tumors.

    PubMed

    Buchgeister, Markus; Grisanti, Salvatore; Süsskind, Daniela; Bamberg, Michael; Paulsen, Frank

    2007-12-01

    A modified swim goggle holding a light spot as an optical guide for actively aligning the eye in a reproducible orientation has been constructed to perform radiotherapy of ocular tumors. This device is compatible with computed tomography (CT) and magnetic resonance imaging systems. Image fusion of these data sets yielded clinically acceptable results. The reproducibility of the eye's positioning is tested by repeated CT. The eye's alignment during radiotherapy is monitored by an infrared TV camera with individual markings of the eye's position on the TV-monitor screen. From 2003-2006, 50 patients were treated with this fixation aid by radiosurgery with good patient compliance.

  3. Status of carbon-ion radiotherapy facilities in Japan

    NASA Astrophysics Data System (ADS)

    Kitagawa, Atsushi

    2013-05-01

    Carbon-ion radiotherapy has large physical and biological advantages, and clinical results performed by HIMAC at NIRS awaken a deep interest. Several hospital-specified facilities are recently under commissioning or construction in Japan. Carbon-ion radiotherapy is based on the advanced technology in wide various fields. In order to promote this treatment method to the daily treatment, constant cooperative efforts by public and private organizations are necessary, i.e. providing of abundant clinical data, technology transfer, personnel training, organizing of the specialists' network, and so on. The present status and future prospects in Japan are reported.

  4. The Tumour Microenvironment after Radiotherapy: Mechanisms of Resistance and Recurrence

    PubMed Central

    Barker, Holly E.; Paget, James T. E.; Khan, Aadil A.; Harrington, Kevin J.

    2016-01-01

    Radiotherapy plays a central part in curing cancer. For decades, most research on improving treatment outcomes has focussed on modulating radiation-induced biological effects on cancer cells. Recently, we have better understood that components within the tumour microenvironment have pivotal roles in determining treatment outcomes. In this Review, we describe vascular, stromal and immunological changes induced in the tumour microenvironment by irradiation and discuss how they may promote radioresistance and tumour recurrence. Subsequently, we highlight how this knowledge is guiding the development of new treatment paradigms in which biologically targeted agents will be combined with radiotherapy. PMID:26105538

  5. Predictors of Acute Esophagitis in Lung Cancer Patients Treated With Concurrent Three-Dimensional Conformal Radiotherapy and Chemotherapy

    SciTech Connect

    Rodriguez, Nuria Algara, Manuel; Foro, Palmira; Lacruz, Marti; Reig, Anna; Membrive, Ismael; Lozano, Joan; Lopez, Jose Luis; Quera, Jaime; Fernandez-Velilla, Enric;