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Sample records for primary fractionated stereotactic

  1. Fractionated Stereotactic Radiotherapy for Facial Nerve Schwannomas.

    PubMed

    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

    2016-02-01

    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

  2. Stereotactic fractionated radiotherapy for the treatment of benign meningiomas

    SciTech Connect

    Candish, Charles; McKenzie, Michael . E-mail: mmckenzi@bccancer.bc.edu; Clark, Brenda G.; Ma, Roy; Lee, Richard; Vollans, Emily; Robar, James; Gete, Ermias; Martin, Monty

    2006-11-15

    Purpose: To assess the use of stereotactic fractionated radiotherapy (SRT) for the treatment of meningiomas. Methods and Materials: Between April 1999 and October 2004, 38 patients underwent SRT. Of 34 patients (36 tumors) assessed, the median age was 53 years. The indication was primary treatment in 26 cases (no histology) and postoperative in 10 cases. The most common sites were cavernous sinus (17), optic nerve (6), and cerebellopontine angle (5). The median gross target volume and planning target volume were 8.9 cm{sup 3} and 18.9 cm{sup 3}, respectively. Stereotactic treatment was delivered with 6-MV photons with static conformal fields (custom-made blocks, 9 patients, and micromultileaf collimator, 25 patients). Median number of fields was six. The median dose prescribed was 50 Gy (range, 45-50.4 Gy) in 28 fractions. The median homogeneity and conformality indices were 1.1 and 1.79, respectively. Results: Treatment was well tolerated. Median follow-up was 26 months with 100% progression-free survival. One patient developed an area of possible radionecrosis related to previous radiotherapy, and 2 men developed mild hypogonadism necessitating testosterone replacement. The vision of 5 of 6 patients with optic pathway meningiomas improved or remained static. Conclusions: Stereotactic fractionated radiotherapy for the treatment of meningiomas is practical, and with early follow-up, seems to be effective.

  3. 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.

  4. Effectiveness of fractionated stereotactic radiotherapy for uveal melanoma

    SciTech Connect

    Muller, Karin; Nowak, Peter; Pan, Connie de; Marijnissen, Johannes P.; Paridaens, Dion A.; Levendag, Peter; Luyten, Gre P.M. . E-mail: g.p.m.luyten@erasmusmc.nl

    2005-09-01

    Purpose: To study the effectiveness and acute side effects of fractionated stereotactic radiation therapy (fSRT) for uveal melanoma. Methods and Materials: Between 1999 and 2003, 38 patients (21 male, 17 female) were included in a prospective, nonrandomized clinical trial (mean follow-up of 25 months). A total dose of 50 Gy was given in 5 consecutive days. A blinking light and a camera (to monitor the position of the diseased eye) were fixed to a noninvasive relocatable stereotactic frame. Primary end points were local control, best corrected visual acuity, and toxicity at 3, 6, 12, and 24 months, respectively. Results: After 3 months (38 patients), the local control was 100%; after 12 months (32 patients) and 24 months (15 patients), no recurrences were seen. The best corrected visual acuity declined from a mean of 0.21 at diagnosis to 0.06 2 years after therapy. The acute side effects after 3 months were as follows: conjunctival symptoms (10), loss of lashes or hair (6), visual symptoms (5), fatigue (5), dry eye (1), cataract (1), and pain (4). One eye was enucleated at 2 months after fSRT. Conclusions: Preliminary results demonstrate that fSRT is an effective and safe treatment modality for uveal melanoma with an excellent local control and mild acute side effects. The follow-up should be prolonged to study both long-term local control and late toxicity.

  5. Nelson's syndrome: single centre experience using the linear accelerator (LINAC) for stereotactic radiosurgery and fractionated stereotactic radiotherapy.

    PubMed

    Wilson, Peter J; Williams, Janet R; Smee, Robert I

    2014-09-01

    Nelson's syndrome is a unique clinical phenomenon of growth of a pituitary adenoma following bilateral adrenalectomies for the control of Cushing's disease. Primary management is surgical, with limited effective medical therapies available. We report our own institution's series of this pathology managed with radiation: prior to 1990, 12 patients were managed with conventional radiotherapy, and between 1990 and 2007, five patients underwent stereotactic radiosurgery (SRS) and two patients fractionated stereotactic radiotherapy (FSRT), both using the linear accelerator (LINAC). Tumour control was equivocal, with two of the five SRS patients having a reduction in tumour volume, one patient remaining unchanged, and two patients having an increase in volume. In the FSRT group, one patient had a decrease in tumour volume whilst the other had an increase in volume. Treatment related morbidity was low. Nelson's syndrome is a challenging clinical scenario, with a highly variable response to radiation in our series. PMID:24825407

  6. Single-Dose Versus Fractionated Stereotactic Radiotherapy for Brain Metastases

    SciTech Connect

    Kim, Yeon-Joo; Cho, Kwan Ho; Kim, Joo-Young; Lim, Young Kyung; Min, Hye Sook; Lee, Sang Hyun; Kim, Ho Jin; Gwak, Ho Shin; Yoo, Heon; Lee, Seung Hoon

    2011-10-01

    Purpose: To evaluate the efficacy of stereotactic radiotherapy in patients with brain metastases by comparing two different treatment regimens, single-dose radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT). Methods and Materials: Between November 2003 and December 2008, 98 patients with brain metastases were included. Fifty-eight patients were treated with SRS, and forty were treated with FSRT. Fractionated stereotactic radiotherapy was used for large lesions or lesions located near critical structures. The median doses were 20 Gy for the SRS group and 36 Gy in 6 fractions for the FSRT group. Results: With a median follow-up period of 7 months, the median survival was 7 months for all patients, with a median of 6 months for the SRS group and 8 months for the FSRT group (p = 0.89). Local progression-free survival (LPFS) rates at 6 months and 1 year were 81% and 71%, respectively, for the SRS group and 97% and 69%, respectively, for the FSRT group (p = 0.31). Despite the fact that FSRT was used for large lesions and lesions in adverse locations, LPFS was not inferior to SRS. Toxicity was more frequently observed in the SRS group than in the FSRT group (17% vs. 5%, p = 0.05). Conclusions: Because patients treated with FSRT exhibited similar survival times and LPFS rates with a lower risk of toxicity in comparison to those treated with SRS, despite the fact that FSRT was used for large lesions and lesions in adverse locations, we find that FSRT can particularly be beneficial for patients with large lesions or lesions located near critical structures. Further investigation is warranted to determine the optimal dose/fractionation.

  7. Fractionated Stereotactic Radiotherapy in Patients With Optic Nerve Sheath Meningioma

    SciTech Connect

    Paulsen, Frank; Doerr, Stefan; Wilhelm, Helmut; Becker, Gerd; Bamberg, Michael; Classen, Johannes

    2012-02-01

    Purpose: To evaluate the effectiveness of fractionated stereotactic radiotherapy (SFRT) in the treatment of optic nerve sheath meningioma (ONSM). Methods and Materials: Between 1993 and 2005, 109 patients (113 eyes) with primary (n = 37) or secondary (n = 76) ONSM were treated according to a prospective protocol with SFRT to a median dose of 54 Gy. All patients underwent radiographic, ophthalmologic, and endocrine analysis before and after SFRT. Radiographic response, visual control, and late side effects were endpoints of the analysis. Results: Median time to last clinical, radiographic, and ophthalmologic follow up was 30.2 months (n = 113), 42.7 months (n = 108), and 53.7 months (n = 91), respectively. Regression of the tumor was observed in 5 eyes and progression in 4 eyes, whereas 104 remained stable. Visual acuity improved in 12, deteriorated in 11, and remained stable in 68 eyes. Mean visual field defects reduced from 33.6% (n = 90) to 17.8% (n = 56) in ipsilateral and from 10% (n = 94) to 6.7% (n = 62) in contralateral eyes. Ocular motility improved in 23, remained stable in 65, and deteriorated in 3 eyes. Radiographic tumor control was 100% at 3 years and 98% at 5 years. Visual acuity was preserved in 94.8% after 3 years and in 90.9% after 5 years. Endocrine function was normal in 90.8% after 3 years and in 81.3% after 5 years. Conclusions: SFRT represents a highly effective treatment for ONSM. Interdisciplinary counseling of the patients is recommended. Because of the high rate of preservation of visual acuity we consider SFRT the standard approach for the treatment of ONSM. Prolonged observation is warranted to more accurately assess late visual impairment. Moderate de-escalation of the radiation dose might improve the preservation of visual acuity and pituitary gland function.

  8. Stereotactic Fractionated Radiotherapy in the Treatment of Juxtapapillary Choroidal Melanoma: The McGill University Experience

    SciTech Connect

    Al-Wassia, Rolina; Dal Pra, Alan; Shun, Kitty; Shaban, Ahmed; Corriveau, Christine; Edelstein, Chaim; Deschenes, Jean; Ruo, Russel; Patrocinio, Horacio; Cury, Fabio L.B.; DeBlois, Francois; Shenouda, George

    2011-11-15

    Purpose: To report our experience with linear accelerator-based stereotactic fractionated radiotherapy in the treatment of juxtapapillary choroidal melanoma. Methods and Materials: We performed a retrospective review of 50 consecutive patients diagnosed with juxtapapillary choroidal melanoma and treated with linear accelerator-based stereotactic fractionated radiotherapy between April 2003 and December 2009. Patients with small to medium sized lesions (Collaborative Ocular Melanoma Study classification) located within 2 mm of the optic disc were included. The prescribed radiation dose was 60 Gy in 10 fractions. The primary endpoints included local control, enucleation-free survival, and complication rates. Results: The median follow-up was 29 months (range, 1-77 months). There were 31 males and 29 females, with a median age of 69 years (range, 30-92 years). Eighty-four percent of the patients had medium sized lesions, and 16% of patients had small sized lesions. There were four cases of local progression (8%) and three enucleations (6%). Actuarial local control rates at 2 and 5 years were 93% and 86%, respectively. Actuarial enucleation-free survival rates at 2 and 5 years were 94% and 84%, respectively. Actuarial complication rates at 2 and 5 years were 33% and 88%, respectively, for radiation-induced retinopathy; 9.3% and 46.9%, respectively, for dry eye; 12% and 53%, respectively, for cataract; 30% and 90%, respectively, for visual loss [Snellen acuity (decimal equivalent), <0.1]; 11% and 54%, respectively, for optic neuropathy; and 18% and 38%, respectively, for neovascular glaucoma. Conclusions: Linear accelerator-based stereotactic fractionated radiotherapy using 60 Gy in 10 fractions is safe and has an acceptable toxicity profile. It has been shown to be an effective noninvasive treatment for juxtapapillary choroidal melanomas.

  9. Fractionated stereotactic radiosurgery for recurrent ependymoma in children

    PubMed Central

    Hoffman, Lindsey M.; Plimpton, S. Reed; Foreman, Nicholas K.; Stence, Nicholas V.; Hankinson, Todd C.; Handler, Michael H.; Hemenway, Molly S.; Vibhakar, Rajeev; Liu, Arthur K.

    2013-01-01

    Outcomes for children with relapsed ependymoma are poor. Re-irradiation is a potentially viable salvage option in these patients. Data were reviewed for 12 patients (median age 5.6 years) with relapsed ependymoma who received fractionated stereotactic radiosurgery (fSRS) following maximal surgical resection from 1995 to 2012. Four patients experienced a second recurrence, including 2 in-field and 2 distant failures. Median time to second recurrence (32 months) was significantly longer than time to first recurrence (24 months) (p = 0.008). Three-year local control was 89 %, and median event free survival from fSRS was 3.4 years. Radiation necrosis was observed in 6 patients, 3 who were symptomatic. In conclusion, fSRS offers durable response with a tolerable toxicity profile in children with recurrent EPN. PMID:24078173

  10. Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

    SciTech Connect

    Rasmussen, Rune; Claesson, Magnus; Stangerup, Sven-Eric; Roed, Henrik; Christensen, Ib Jarle; Caye-Thomasen, Per; Juhler, Marianne

    2012-08-01

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

  11. [FRACTIONATED STEREOTACTIC RADIOSURGERY: A GAME CHANGER FOR NEUROSURGERY].

    PubMed

    Nissim, Ouzi; Spiegelmann, Roberto

    2016-05-01

    The article by Dr. Cohen-Inbar published in this issue of Harefuah is a timely review that brings to the general medical community the recent important developments in the field of radiosurgery--the evolution of multi-session radiosurgery [or "FSR", standing for Fractionated Stereotactic Radiation]. Radiosurgery and FSR continue to have a tremendous impact on modern neurosurgery. Sharing sub-millimetric accuracy in radiation delivery made possible by real-time-imaging positioning, frameless single and multisession radiosurgery have become two faces of a therapeutic technique with wide application in the field of intracranial pathology. Blending dose fractionation with delivery precision, FSR is a hybrid tool that can be implemented safely and effectively for practically any intra-cranial pathology without restrictions of volume or location. Dr. Cohen Inbar reviews the available data regarding doses, fractionation schemes, and results for the different pathologies in which FSR is being increasingly applied. FSR, as single-dose radiosurgery since the late 1980s, has changed the practice of neurosurgery. Radical microsorgical tumor removal at any cost in demanding intracranial locations has been replaced by upfront conservative volume-reduction surgery, leaving the more complicated part of those tumors to safer elimination by precise irradiation in single or multiple sessions. In Israel, further to the first unit operative since 1993 at the Sheba Medical Center, 3 new active LINAC based treatment sites have been added in recent years, with facilities either planned or under construction in the remaining major medical centers with neurosurgical and radiotherapy resources. They are evidence of the central role this modality has captured in the management of intracranial pathology. PMID:27526561

  12. Stereotactic Body Radiotherapy for Primary Lung Cancer at a Dose of 50 Gy Total in Five Fractions to the Periphery of the Planning Target Volume Calculated Using a Superposition Algorithm

    SciTech Connect

    Takeda, Atsuya; Sanuki, Naoko; Kunieda, Etsuo Ohashi, Toshio; Oku, Yohei; Takeda, Toshiaki; Shigematsu, Naoyuki; Kubo, Atsushi

    2009-02-01

    Purpose: To retrospectively analyze the clinical outcomes of stereotactic body radiotherapy (SBRT) for patients with Stages 1A and 1B non-small-cell lung cancer. Methods and Materials: We reviewed the records of patients with non-small-cell lung cancer treated with curative intent between Dec 2001 and May 2007. All patients had histopathologically or cytologically confirmed disease, increased levels of tumor markers, and/or positive findings on fluorodeoxyglucose positron emission tomography. Staging studies identified their disease as Stage 1A or 1B. Performance status was 2 or less according to World Health Organization guidelines in all cases. The prescribed dose of 50 Gy total in five fractions, calculated by using a superposition algorithm, was defined for the periphery of the planning target volume. Results: One hundred twenty-one patients underwent SBRT during the study period, and 63 were eligible for this analysis. Thirty-eight patients had Stage 1A (T1N0M0) and 25 had Stage 1B (T2N0M0). Forty-nine patients were not appropriate candidates for surgery because of chronic pulmonary disease. Median follow-up of these 49 patients was 31 months (range, 10-72 months). The 3-year local control, disease-free, and overall survival rates in patients with Stages 1A and 1B were 93% and 96% (p = 0.86), 76% and 77% (p = 0.83), and 90% and 63% (p = 0.09), respectively. No acute toxicity was observed. Grade 2 or higher radiation pneumonitis was experienced by 3 patients, and 1 of them had fatal bacterial pneumonia. Conclusions: The SBRT at 50 Gy total in five fractions to the periphery of the planning target volume calculated by using a superposition algorithm is feasible. High local control rates were achieved for both T2 and T1 tumors.

  13. Long-Term Outcomes of Vestibular Schwannomas Treated With Fractionated Stereotactic Radiotherapy: An Institutional Experience

    SciTech Connect

    Kapoor, Sumit; Batra, Sachin; Carson, Kathryn; Shuck, John; Kharkar, Siddharth; Gandhi, Rahul; Jackson, Juan; Wemmer, Jan; Terezakis, Stephanie; Shokek, Ori; Kleinberg, Lawrence; Rigamonti, Daniele

    2011-11-01

    Purpose: We assessed clinical outcome and long-term tumor control after fractionated stereotactic radiotherapy (FSRT) for unilateral schwannoma. Methods and Materials: Between 1995 and 2007, 496 patients were treated with fractionated stereotactic radiotherapy at Johns Hopkins Hospital (Baltimore, MD); 385 patients had radiologic follow-up that met the inclusion criteria. The primary endpoint was treatment failure. Secondary endpoints were radiologic progression and clinical outcome. Logistic regression analysis assessed the association of age, race, tumor side, sex, and pretreatment symptoms. Results: In 11 patients (3%) treatment failed, and they required salvage (microsurgical) treatment. Radiologic progression was observed in 116 patients (30.0%), including 35 patients (9%) in whom the treatment volume more than doubled during the follow-up period, although none required surgical resection. Tumors with baseline volumes of less than 1 cm{sup 3} were 18.02 times more likely to progress than those with tumor volumes of 1 cm{sup 3} or greater (odds ratio, 18.02; 95% confidence interval, 4.25-76.32). Treatment-induced neurologic morbidity included 8 patients (1.6%) with new facial weakness, 12 patients (2.8%) with new trigeminal paresthesias, 4 patients (0.9%) with hydrocephalus (1 communicating and 3 obstructive), and 2 patients (0.5%) with possibly radiation-induced neoplasia. Conclusions: Although the rate of treatment failure is low (3%), careful follow-up shows that radiologic progression occurs frequently. When reporting outcome, the 'no salvage surgery needed' and 'no additional treatment needed' criteria for treatment success need to be complemented by the radiologic data.

  14. Fractionated Stereotactic Radiotherapy in the Treatment of Vestibular Schwannoma (Acoustic Neuroma): Predicting the Risk of Hydrocephalus;Vestibular schwannoma; Hydrocephalus; Fractionated; Stereotactic radiotherapy

    SciTech Connect

    Powell, Ceri; Micallef, Caroline; Gonsalves, Adam; Wharram, Bev; Ashley, Sue; Brada, Michael

    2011-07-15

    Purpose: To determine the incidence and predictive factors for the development of hydrocephalus in patients with acoustic neuromas (AN) treated with fractionated stereotactic radiotherapy. Patients and Methods: Seventy-two patients with AN were treated with fractionated stereotactic radiotherapy between 1998 and 2007 (45-50 Gy in 25-30 fractions over 5 to 6 weeks). The pretreatment MRI scan was assessed for tumor characteristics and anatomic distortion independently of subsequent outcome and correlated with the risk of hydrocephalus. Results: At a median follow-up of 49 months (range, 1-120 months), 5-year event-free survival was 95%. Eight patients (11%) developed hydrocephalus within 19 months of radiotherapy, which was successfully treated. On univariate analysis, pretreatment factors predictive of hydrocephalus were maximum diameter (p = 0.005), proximity to midline (p = 0.009), displacement of the fourth ventricle (p = 0.02), partial effacement of the fourth ventricle (p < 0.001), contact with the medulla (p = 0.005), and more brainstem structures (p = 0.004). On multivariate analysis, after adjusting for fourth ventricular effacement, no other variables remained independently associated with hydrocephalus formation. Conclusions: Fractionated stereotactic radiotherapy results in excellent tumor control of AN, albeit with a risk of developing hydrocephalus. Patients at high risk, identified as those with larger tumors with partial effacement of the fourth ventricle before treatment, should be monitored more closely during follow-up. It would also be preferable to offer treatment to patients with progressive AN while the risk of hydrocephalus is low, before the development of marked distortion of fourth ventricle before tumor diameter significantly exceeds 2 cm.

  15. Stereotactic body radiotherapy for primary prostate cancer: a systematic review.

    PubMed

    Tan, Tze-Jian; Siva, Shankar; Foroudi, Farshad; Gill, Suki

    2014-10-01

    Stereotactic body radiotherapy (SBRT) for prostate cancer allows overall treatment times to be reduced to as little as 1 week while maintaining a non-invasive approach. This study provides a comprehensive summary of the literature relating to SBRT in prostate cancer. A systematic review of the relevant literature was performed using structured search terms. Fourteen phase I-II trials and retrospective studies using SBRT for the treatment of prostate cancer were used. Three studies were identified which addressed cost. Dose fractionation, radiotherapy procedures, biochemical progression-free survival, toxicity, cost and quality of life were critically appraised. A total of 1472 patients were examined across studies. Median follow-up ranged from 11 to 60 months. The most common dose fractionation was 35-36.25 Gy in five fractions, used in nine out of 14 studies. Ten of 14 studies used CyberKnife. The overall biochemical progression-free survival ranged 81-100%. Acute grade 2 urinary and rectal toxicities were reported in 5-42% and 0-27% of patients, respectively. Acute grade 3 or more urinary and rectal toxicity were 0.5% and 0%, respectively. Late grade 2 urinary toxicity was reported in 0-29% of patients, while 1.3% had a late grade 3 urinary toxicity. There were no late grade 4 urinary toxicities seen. Late grade 2 rectal toxicity was reported in 0-11%, while 0.5% had a late grade 3 rectal toxicity. Late grade 4 rectal toxicity was reported in 0.2% of patients. PMID:25155286

  16. 3D quantitative assessment of response to fractionated stereotactic radiotherapy and single-session stereotactic radiosurgery of vestibular schwannoma

    PubMed Central

    Schneider, T.; Chapiro, J.; Lin, M.; Geschwind, J. F.; Kleinberg, L.; Rigamonti, D.; Jusué-Torres, I.; Marciscano, A. E.; Yousem, D. M.

    2015-01-01

    Objectives To determine clinical outcome of patients with vestibular schwannoma (VS) after treatment with fractionated stereotactic radiotherapy (FSRT) and single-session stereotactic radiosurgery (SRS) by using 3D quantitative response assessment on MRI. Materials This retrospective analysis included 162 patients who underwent radiation therapy for sporadic VS. Measurements on T1-weighted contrast-enhanced MRI (in 2-year post-therapy intervals: 0–2, 2–4, 4–6, 6–8, 8–10, and 10–12 years) were taken for total tumour volume (TTV) and enhancing tumour volume (ETV) based on a semi-automated technique. Patients were considered non-responders (NRs) if they required subsequent microsurgical resection or developed radiological progression and tumour-related symptoms. Results Median follow-up was 4.1 years (range: 0.4–12.0). TTV and ETV decreased for both the FSRT and SRS groups. However, only the FSRT group achieved significant tumour shrinkage (p < 0.015 for TTV, p < 0.005 for ETV over time). The 11 NRs showed proportionally greater TTV (median TTV pre-treatment: 0.61 cm3, 8–10 years after: 1.77 cm3) and ETV despite radiation therapy compared to responders (median TTV pre-treatment: 1.06 cm3; 10–12 years after: 0.81 cm3; p = 0.001). Conclusion 3D quantification of VS showed a significant decrease in TTV and ETV on FSRT-treated patients only. NRs had significantly greater TTV and ETV over time. PMID:26139318

  17. Robotic Image-Guided Stereotactic Radiotherapy, for Isolated Recurrent Primary, Lymph Node or Metastatic Prostate Cancer

    SciTech Connect

    Jereczek-Fossa, Barbara Alicja; Beltramo, Giancarlo; Fariselli, Laura; Fodor, Cristiana; Santoro, Luigi; Vavassori, Andrea; Zerini, Dario; Gherardi, Federica; Ascione, Carmen; Bossi-Zanetti, Isa; Mauro, Roberta; Bregantin, Achille; Bianchi, Livia Corinna; De Cobelli, Ottavio; Orecchia, Roberto

    2012-02-01

    Purpose: To evaluate the outcome of robotic CyberKnife (Accuray, Sunnyvale, CA)-based stereotactic radiotherapy (CBK-SRT) for isolated recurrent primary, lymph node, or metastatic prostate cancer. Methods and Materials: Between May 2007 and December 2009, 34 consecutive patients/38 lesions were treated (15 patients reirradiated for local recurrence [P], 4 patients reirradiated for anastomosis recurrence [A], 16 patients treated for single lymph node recurrence [LN], and 3 patients treated for single metastasis [M]). In all but 4 patients, [{sup 11}C]choline positron emission tomography/computed tomography was performed. CBK-SRT consisted of reirradiation and first radiotherapy in 27 and 11 lesions, respectively. The median CBK-SRT dose was 30 Gy in 4.5 fractions (P, 30 Gy in 5 fractions; A, 30 Gy in 5 fractions; LN, 33 Gy in 3 fractions; and M, 36 Gy in 3 fractions). In 18 patients (21 lesions) androgen deprivation was added to CBK-SRT (median duration, 16.6 months). Results: The median follow-up was 16.9 months. Acute toxicity included urinary events (3 Grade 1, 2 Grade 2, and 2 Grade 3 events) and rectal events (1 Grade 1 event). Late toxicity included urinary events (3 Grade 1, 2 Grade 2, and 2 Grade 3 events) and rectal events (1 Grade 1 event and 1 Grade 2 event). Biochemical response was observed in 32 of 38 evaluable lesions. Prostate-specific antigen stabilization was seen for 4 lesions, and in 2 cases prostate-specific antigen progression was reported. The 30-month progression-free survival rate was 42.6%. Disease progression was observed for 14 lesions (5, 2, 5, and 2 in Groups P, A, LN, and M respectively). In only 3 cases, in-field progression was seen. At the time of analysis (May 2010), 19 patients are alive with no evidence of disease and 15 are alive with disease. Conclusions: CyberKnife-based stereotactic radiotherapy is a feasible approach for isolated recurrent primary, lymph node, or metastatic prostate cancer, offering excellent in-field tumor

  18. Local control rates with five-fraction stereotactic body radiotherapy for oligometastatic cancer to the lung

    PubMed Central

    Chen, Yuhchyau; Hare, Mary Z.; Usuki, Kenneth Y.; Zhang, Hong; Lundquist, Thomas; Joyce, Neil; Schell, Michael C.; Milano, Michael T.

    2014-01-01

    Objective To report our institutional experience with five fractions of daily 8-12 Gy stereotactic body radiotherapy (SBRT) for the treatment of oligometastatic cancer to the lung. Methods Thirty-four consecutive patients with oligometastatic cancers to the lung were treated with image-guided SBRT between 2008 and 2011. Patient age ranged from 38 to 81 years. There were 17 males and 17 females. Lung metastases were from the following primary cancer types: colon cancer (n=13 patients), head and neck cancer (n=6), breast cancer (n=4), melanoma (n=4), sarcoma (n=4) and renal cell carcinoma (n=3). The median prescription dose was 50 Gy in five fractions (range, 40-60 Gy) to the isocenter, with the 80% isodose line encompassing the planning target volume (PTV) [defined as gross tumor volume (GTV) + 7-11 mm volumetric expansion]. The follow-up interval ranged from 2.4-54 months, with a median of 16.7 months. Results The 1-, 2-, and 3-year patient local control (LC) rates for all patients were 93%, 88%, and 80% respectively. The 1-, 2-, and 3-year overall survival (OS) rates were 62%, 44%, and 23% respectively. The 1- and 2-year patient LC rates were 95% and 88% for tumor size 1-2 cm (n=25), and 86% for tumor size 2-3 cm (n=7). The majority (n=4) of local failures occurred within 12 months. No patient experienced local failure after 12 months except for one patient with colon cancer whose tumors progressed locally at 26 months. All five patients with local recurrences had colorectal cancer. Statistical analyses showed that age, gender, previous chemotherapy, previous surgery or radiation had no significant effect on LC rates. No patient was reported to have any symptomatic pneumonitis at any time point. Conclusions SBRT for oligometastatic disease to the lung using 8-12 Gy daily fractions over five treatments resulted in excellent 1- and 2-year LC rates. Most local failures occurred within the first 12 months, with five local failures associated with colorectal cancer

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

    SciTech Connect

    Stiebel-Kalish, Hadas; Reich, Ehud; Gal, Lior; Rappaport, Zvi Harry; Nissim, Ouzi; Pfeffer, Raphael; Spiegelmann, Roberto

    2012-02-01

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

  20. Extracranial stereotactic body radiotherapy. Review of main SBRT features and indications in primary tumors

    PubMed Central

    Rubio, Carmen; Morera, Rosa; Hernando, Ovidio; Leroy, Thomas.; Lartigau, S. Eric

    2013-01-01

    Aim Review of main SBRT features and indications in primary tumors. Background Stereotactic body radiotherapy has been developed in the last few years. SBRT allows the hypofractionated treatment of extra cranial tumors, using either a single or limited number of dose fractions, and resulting in the delivery of a high biological effective dose with low toxicity. Material and methods SBRT requires a high level of accuracy for all phases of the treatment process: effective patient immobilization, precise target localization, highly conformed dosimetry and image guided systems for treatment verification. The implementation of SBRT in routine requires a careful considering of organ motion. Gating and tracking are effective ways to do so, and less invasive technologies “fiducials free” have been developed. Due to the hypofractionated scheme, the physician must pay attention to new dosimetric constraints in organ at risk and new radiobiological models are needed to assess the optimal fractionation and dose schemes. Results Currently, SBRT is safe and effective to treat primary tumors, which are otherwise untreatable with conventional radiotherapy or surgery. SBRT has quickly developed because of its excellent results in terms of tolerance and its high locoregional control rates. SBRT indications in primary tumors, such as lung primary tumors, have become a standard of care for inoperable patients. SBRT seems to be effective in many others indications in curative or palliative intent such as liver primary tumors, and novel indications and strategies are currently emerging in prostate cancer, head and neck tumor recurrences or pelvis reirradiations. Conclusion Currently, SBRT is mainly used when there is no other therapeutic alternative for the patient. This is due to the lack of randomized trials in these settings. However, the results shown in retrospective studies let us hope to impose SBRT as a new standard of care for many patients in the next few years. PMID

  1. Five-Year Outcomes of High-Dose Single-Fraction Spinal Stereotactic Radiosurgery

    SciTech Connect

    Moussazadeh, Nelson; Lis, Eric; Katsoulakis, Evangelia; Kahn, Sweena; Svoboda, Marek; DiStefano, Natalie M.; McLaughlin, Lily; Bilsky, Mark H.; Yamada, Yoshiya; Laufer, Ilya

    2015-10-01

    Purpose: To characterize local tumor control and toxicity risk in very long-term survivors (>5 years) after high-dose spinal image guided, intensity modulated radiation therapy delivered as single-dose stereotactic radiosurgery (SRS). Previously published spinal SRS outcome analyses have included a heterogeneous population of cancer patients, mostly with short survival. This is the first study reporting the long-term tumor control and toxicity profiles after high-dose single-fraction spinal SRS. Methods and Materials: The study population included all patients treated from June 2004 to July 2009 with single-fraction spinal SRS (dose 24 Gy) who had survived at least 5 years after treatment. The endpoints examined included disease progression, surgical or radiation retreatment, in-field fracture development, and radiation-associated toxicity, scored using the Radiation Therapy Oncology Group radiation morbidity scoring criteria and the Common Terminology Criteria for Adverse Events, version 4.0. Local control and fracture development were assessed using Kaplan-Meier analysis. Results: Of 278 patients, 31 (11.1%), with 36 segments treated for spinal tumors, survived at least 5 years after treatment and were followed up radiographically and clinically for a median of 6.1 years (maximum 102 months). The histopathologic findings for the 5-year survivors included radiation-resistant metastases in 58%, radiation-sensitive metastases in 22%, and primary bone tumors in 19%. In this selected cohort, 3 treatment failures occurred at a median of 48.6 months, including 2 recurrences in the radiation field and 1 patient with demonstrated progression at the treatment margins. Ten lesions (27.8%) were associated with acute grade 1 cutaneous or gastrointestinal toxicity. Delayed toxicity ≥3 months after treatment included 8 cases (22.2%) of mild neuropathy, 2 (5.6%) of gastrointestinal discomfort, 8 (22.2%) of dermatitides, and 3 (8.3%) of myalgias/myositis. Thirteen

  2. Stereotactic ablative body radiotherapy (SABR) for primary and secondary lung tumours

    PubMed Central

    Gaya, Andrew

    2012-01-01

    Abstract Stereotactic ablative body radiotherapy (SABR) represents a technological breakthrough in radiotherapy technique, with proven benefits to patients in terms of improved tumour control and overall survival. The key components of SABR are described. The current evidence base for SABR for the treatment of primary and secondary lung tumours is appraised, and key ongoing trials are identified. PMID:23023165

  3. Single Fraction Versus Fractionated Linac-Based Stereotactic Radiotherapy for Vestibular Schwannoma: A Single-Institution Experience

    SciTech Connect

    Collen, Christine; Ampe, Ben; Gevaert, Thierry; Moens, Maarten; Linthout, Nadine; De Ridder, Mark; Verellen, Dirk; D'Haens, Jean; Storme, Guy

    2011-11-15

    Purpose: To evaluate and compare outcomes for patients with vestibular schwannoma (VS) treated in a single institution with linac-based stereotactic radiosurgery (SRS) or by fractionated stereotactic radiotherapy (SRT). Methods and Materials: One hundred and nineteen patients (SRS = 78, SRT = 41) were treated. For both SRS and SRT, beam shaping is performed by a mini-multileaf collimator. For SRS, a median single dose of 12.5 Gy (range, 11-14 Gy), prescribed to the 80% isodose line encompassing the target, was applied. Of the 42 SRT treatments, 32 treatments consisted of 10 fractions of 3-4 Gy, and 10 patients received 25 sessions of 2 Gy, prescribed to the 100% with the 95% isodose line encompassing the planning target volume. Mean largest tumor diameter was 16.6 mm in the SRS and 24.6 mm in the SRT group. Local tumor control, cranial nerve toxicity, and preservation of useful hearing were recorded. Any new treatment-induced cranial nerve neuropathy was scored as a complication. Results: Median follow-up was 62 months (range, 6-136 months), 5 patients progressed, resulting in an overall 5-year local tumor control of 95%. The overall 5-year facial nerve preservation probability was 88% and facial nerve neuropathy was statistically significantly higher after SRS, after prior surgery, for larger tumors, and in Koos Grade {>=}3. The overall 5-year trigeminal nerve preservation probability was 96%, not significantly influenced by any of the risk factors. The overall 4-year probability of preservation of useful hearing (Gardner-Robertson score 1 or 2) was 68%, not significantly different between SRS or SRT (59% vs. 82%, p = 0.089, log rank). Conclusion: Linac-based RT results in good local control and acceptable clinical outcome in small to medium-sized vestibular schwannomas (VSs). Radiosurgery for large VSs (Koos Grade {>=}3) remains a challenge because of increased facial nerve neuropathy.

  4. Fractionated Stereotactic Radiotherapy as Reirradiation for Locally Recurrent Head and Neck Cancer

    SciTech Connect

    Roh, Kwang-Won; Jang, Ji-Sun; Kim, Min-Sik; Sun, Dong-Il; Kim, Bum-Soo; Jung, So-Lyoung; Kang, Jin-Hyoung; Yoo, Eun-Jung; Yoon, Sei-Chul; Jang, Hong-Seok; Chung, Su-Mi; Kim, Yeon-Sil

    2009-08-01

    Purpose: We report early preliminary experience with CyberKnife radiosurgery (RS) as salvage treatment for locally recurrent head and neck cancer (HNC). Methods and Materials: Between March 2004 and August 2006, 36 patients (44 sites) were treated with CyberKnife RS as reirradiation for locally recurrent HNC. Treatment sites were as follows: nasopharynx (8), maxillary sinus (8), neck lymph nodes (8), skull base (7), nasal cavity (4), retropharyngeal lymph nodes (3), orbit (2), and others (4). Total doses administered were 18-40 Gy (median, 30 Gy) in 3 to 5 fractions to the 65%-85% isodose line for 3-5 consecutive days. Previous external radiation dose ranged from 39.6 to 134.4 Gy (median, 70.2 Gy). Gross tumor volume ranged from 0.2 to 114.9 cm{sup 3} (median, 22.6 cm{sup 3}). Median follow-up was 17.3 months. Results: Thirty-five of 44 sites were evaluated for response. Fifteen (42.9%) sites achieved complete response, 13 sites (37.1%) achieved a partial response, 3 (8.6%) sites maintained stable disease, and 4 sites (11.4%) showed tumor progression. Grade III acute complications were noted in 13 patients. Late complications were observed in three patients (1 bone necrosis, 2 soft tissue necrosis) during follow-up. Conclusion: These preliminary results suggest that fractionated stereotactic radiosurgery is an effective treatment modality as a salvage treatment with good short-term local control. The early overall response rate is encouraging. However, more experience and a longer follow-up are necessary to determine the role of fractionated stereotactic radiosurgery as a salvage treatment of locally recurrent HNC and to define long-term complications.

  5. Long-term results of fractionated stereotactic radiotherapy as third-line treatment in acromegaly.

    PubMed

    Diallo, Alpha M; Colin, Philippe; Litre, Claude F; Diallo, Mamadou M; Decoudier, Bénédicte; Bertoin, Florence; Higel, Brigitte; Patey, Martine; Rousseaux, Pascal; Delemer, Brigitte

    2015-12-01

    The treatment of acromegaly is based on surgery, drugs, and radiotherapy as a third-line option. Fractionated stereotactic radiotherapy (FSRT) is a new technique with a need for long-term evaluation. The purpose of the study was to evaluate long-term results of FSRT in acromegaly. Overall, 34 patients [sex ratio 1.12, age 45 (5-65) years] with a pituitary adenoma of 24.5 (9-76) mm including 20 invasive tumors were treated by radiotherapy in fractionated stereotactic conditions delivering 50 gy in 27 sessions. Baseline growth hormone (GH) and IGF1 levels were 18 (±14.5) and 632.6 (±339) µg/L, respectively. Indications of FSRT were failure of surgery and drug treatments (n = 30) or contraindication/refusal of surgery (n = 4). Hormonal control was defined by normal age- and sex-adjusted IGF1. Remission was defined by hormonal control after withdrawal of drugs for a minimum of three consecutive months. Data were analyzed in SPSS software with a significance level at p < 0.05. After a mean follow-up of 152 months, hormonal control was achieved in 33 patients (97 %) with withdrawal of drugs in 13 patients (38.2 %) without any recurrence. Factors found to be significantly associated to remission in a multivariate Cox regression were lower baseline hormone levels (GH and IGF1) and smaller tumor size. Tumor control was achieved in all patients. Acquired hypopituitarism after radiotherapy was the main side effect reported with a rate of 39 %. FSRT seems to be an effective and well tolerated third-line treatment of acromegaly, particularly adapted to macro adenomas treatment. PMID:25956280

  6. Stereotactic Body Radiotherapy as Primary Treatment for Elderly Patients with Medically Inoperable Head and Neck Cancer

    PubMed Central

    Vargo, John A.; Ferris, Robert L.; Clump, David A.; Heron, Dwight E.

    2014-01-01

    Purpose: With a growing elderly population, elderly patients with head and neck cancers represent an increasing challenge with limited prospective data to guide management. The complex interplay between advanced age, associated co-morbidities, and conventional local therapies, such as surgery and external beam radiotherapy ± chemotherapy, can significantly impact elderly patients’ quality of life (QoL). Stereotactic body radiotherapy (SBRT) is a well-established curative strategy for medical-inoperable early-stage lung cancers even in elderly populations; however, there is limited data examining SBRT as primary therapy in head and neck cancer. Material/methods: Twelve patients with medically inoperable head and neck cancer treated with SBRT ± cetuximab from 2002 to 2013 were retrospectively reviewed. SBRT consisted of primarily 44 Gy in five fractions delivered on alternating days over 1–2 weeks. Concurrent cetuximab was administered at a dose of 400 mg/m2 on day −7 followed by 250 mg/m2 on day 0 and +7 in n = 3 (25%). Patient-reported quality of life (PRQoL) was prospectively recorded using the previously validated University of Washington quality of life revised (UW-QoL-R). Results: Median clinical follow-up was 6 months (range: 0.5–29 months). The 1-year actuarial local progression-free survival, distant progression-free survival, progression-free survival, and overall survival for definitively treated patients were 69, 100, 69, and 64%, respectively. One patient (8%) experienced acute grade 3 dysphagia and one patient (8%) experienced late grade 3 mucositis; there were no grade 4–5 toxicities. Prospective collection of PRQoL as assessed by UW-QoL-R was preserved across domains. Conclusion: Stereotactic body radiotherapy shows encouraging survival and relatively low toxicity in elderly patients with unresectable head and neck cancer, which may provide an aggressive potentially curative local therapy while maintaining QoL. PMID

  7. Preliminary Results of Fractionated Stereotactic Radiotherapy After Cyst Drainage for Craniopharyngioma in Adults

    SciTech Connect

    Kanesaka, Naoto; Mikami, Ryuji; Nakayama, Hidetsugu; Nogi, Sachika; Tajima, Yu; Nakajima, Nobuyuki; Wada, Jun; Miki, Tamotsu; Haraoka, Jou; Okubo, Mitsuru; Sugahara, Shinji; Tokuuye, Koichi

    2012-03-15

    Purpose: To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) for craniopharyngioma. Methods and Materials: Between 1999 and 2005, 16 patients with craniopharyngioma were referred to Tokyo Medical University Hospital. They received FSRT alone after histologic confirmation by needle biopsy and underwent cyst drainage via endoscopy. The median prescription dose fraction was 30 Gy in six fractions. All patients except 1 were followed up until December 2009 or death. Results: The median follow-up period was 52 months (range, 4-117 months). Of the 17 patients, 3 experienced recurrence 4 to 71 months after FSRT. The 3-year local control rate was 82.4%. One patient died of thyroid cancer, and the 3-year survival rate was 94.1%. Eight patients had improved visual fields at a median of 2.5 months after FSRT, but hormonal functions did not improve in any patient. Conclusions: FSRT after cyst drainage seems to be safe and effective for patients with craniopharyngiomas, and it may be a safe alternative to surgery.

  8. 2D/3D Image fusion for accurate target localization and evaluation of a mask based stereotactic system in fractionated stereotactic radiotherapy of cranial lesions

    SciTech Connect

    Jin, J.-Y.; Ryu, Samuel; Faber, Kathleen; Mikkelsen, Tom; Chen Qing; Li Shidong; Movsas, Benjamin

    2006-12-15

    The purpose of this study was to evaluate the accuracy of a two-dimensional (2D) to three-dimensional (3D) image-fusion-guided target localization system and a mask based stereotactic system for fractionated stereotactic radiotherapy (FSRT) of cranial lesions. A commercial x-ray image guidance system originally developed for extracranial radiosurgery was used for FSRT of cranial lesions. The localization accuracy was quantitatively evaluated with an anthropomorphic head phantom implanted with eight small radiopaque markers (BBs) in different locations. The accuracy and its clinical reliability were also qualitatively evaluated for a total of 127 fractions in 12 patients with both kV x-ray images and MV portal films. The image-guided system was then used as a standard to evaluate the overall uncertainty and reproducibility of the head mask based stereotactic system in these patients. The phantom study demonstrated that the maximal random error of the image-guided target localization was {+-}0.6 mm in each direction in terms of the 95% confidence interval (CI). The systematic error varied with measurement methods. It was approximately 0.4 mm, mainly in the longitudinal direction, for the kV x-ray method. There was a 0.5 mm systematic difference, primarily in the lateral direction, between the kV x-ray and the MV portal methods. The patient study suggested that the accuracy of the image-guided system in patients was comparable to that in the phantom. The overall uncertainty of the mask system was {+-}4 mm, and the reproducibility was {+-}2.9 mm in terms of 95% CI. The study demonstrated that the image guidance system provides accurate and precise target positioning.

  9. Fractionated Stereotactic Radiotherapy Treatment of Cavernous Sinus Meningiomas: A Study of 100 Cases

    SciTech Connect

    Litre, Claude Fabien Colin, Philippe; Noudel, Remy; Peruzzi, Philippe; Bazin, Arnaud; Sherpereel, Bernard; Bernard, Marie Helene; Rousseaux, Pascal

    2009-07-15

    Purpose: We discuss our experiences with fractionated stereotactic radiotherapy (FSR) in the treatment of cavernous sinus meningiomas. Methods and Materials: From 1995 to 2006, we monitored 100 patients diagnosed with cavernous sinus meningiomas; 84 female and 16 male patients were included. The mean patient age was 56 years. The most common symptoms were a reduction in visual acuity (57%), diplopia (50%), exophthalmy (30%), and trigeminal neuralgia (34%). Surgery was initially performed on 26 patients. All patients were treated with FSR. A total of 45 Gy was administered to the lesion, with 5 fractions of 1.8 Gy completed each week. Patient treatment was performed using a Varian Clinac linear accelerator used for cranial treatments and a micro-multileaf collimator. Results: No side effects were reported. Mean follow-up period was 33 months, with 20% of patients undergoing follow-up evaluation of more than 4 years later. The tumor control rate at 3 years was 94%. Three patients required microsurgical intervention because FSR proved ineffective. In terms of functional symptoms, an 81% improvement was observed in patients suffering from exophthalmy, with 46% of these patients being restored to full health. A 52% improvement was observed in diplopia, together with a 67% improvement in visual acuity and a 50% improvement in type V neuropathy. Conclusions: FSR facilitates tumor control, either as an initial treatment option or in combination with microsurgery. In addition to being a safe procedure with few side effects, FSR offers the significant benefit of superior functional outcomes.

  10. Reirradiation of recurrent salivary gland malignancies with fractionated stereotactic body radiation therapy.

    PubMed

    Karam, Sana D; Snider, James W; Wang, Hongkun; Wooster, Margaux; Lominska, Christopher; Deeken, John; Newkirk, Kenneth; Davidson, Bruce; Harter, K William

    2012-06-01

    PURPOSE: The purpose of this study was to review a single-institution experience with the reirradiation of recurrent salivary gland tumors using fractionated stereotactic radiosurgery (SBRT). METHODS: Between 2003 and 2011, 18 patients diagnosed with recurrent, previously irradiated, salivary gland carcinomas were treated with SBRT reirradiation. Median age was 68 for all patients with most tumors being of major salivary gland origin. Most patients did not undergo surgical resection, and among those that did, all had positive margins. Only seven patients received chemotherapy, and the median SBRT dose was 30 Gy given in five fractions with a median cumulative dose of 91.1 Gy. RESULTS: The median overall survival (OS), progression-free survival (PFS), and local control (LRC) were 11.5, 3.5, and 5.5 months, respectively. The 2-year OS, PFS, and LRC rates were 39%, 24%, and 53%, respectively. Statistical analysis identified presence of gross disease and interval to reirradiation as negative predictors of survival outcomes on both univariate and multivariate analyses (p < 0.05). On multivariate analysis, tumor volume was a negative predictor of survival outcomes (p < 0.05). Long-term toxicity analysis revealed four patients in the reirradiated group with soft tissue necrosis, which correlated with the cumulative dose (p = 0.01). CONCLUSION: Our data suggest that SBRT is a reasonable treatment option for reirradiation of salivary gland tumors, but further studies are warranted. PMID:23440688

  11. Planned Two-Fraction Proton Beam Stereotactic Radiosurgery for High-Risk Inoperable Cerebral Arteriovenous Malformations

    SciTech Connect

    Hattangadi, Jona A.; Chapman, Paul H.; Bussiere, Marc R.; Niemierko, Andrzej; Ogilvy, Christopher S.; Rowell, Alison; Daartz, Juliane; Loeffler, Jay S.; Shih, Helen A.

    2012-06-01

    Purpose: To evaluate patients with high-risk cerebral arteriovenous malformations (AVMs), based on eloquent brain location or large size, who underwent planned two-fraction proton stereotactic radiosurgery (PSRS). Methods and Materials: From 1991 to 2009, 59 patients with high-risk cerebral AVMs received two-fraction PSRS. Median nidus volume was 23 cc (range, 1.4-58.1 cc), 70% of cases had nidus volume {>=}14 cc, and 34% were in critical locations (brainstem, basal ganglia). Median AVM score based on age, AVM size, and location was 3.19 (range, 0.9-6.9). Many patients had prior surgery or embolization (40%) or prior PSRS (12%). The most common prescription was 16 Gy radiobiologic equivalent (RBE) in two fractions, prescribed to the 90% isodose. Results: At a median follow-up of 56.1 months, 9 patients (15%) had total and 20 patients (34%) had partial obliteration. Patients with total obliteration received higher total dose than those with partial or no obliteration (mean dose, 17.6 vs. 15.5 Gy (RBE), p = 0.01). Median time to total obliteration was 62 months (range, 23-109 months), and 5-year actuarial rate of partial or total obliteration was 33%. Five-year actuarial rate of hemorrhage was 22% (95% confidence interval, 12.5%-36.8%) and 14% (n = 8) suffered fatal hemorrhage. Lesions with higher AVM scores were more likely to hemorrhage (p = 0.024) and less responsive to radiation (p = 0.026). The most common complication was Grade 1 headache acutely (14%) and long term (12%). One patient developed a Grade 2 generalized seizure disorder, and two had mild neurologic deficits. Conclusions: High-risk AVMs can be safely treated with two-fraction PSRS, although total obliteration rate is low and patients remain at risk for future hemorrhage. Future studies should include higher doses or a multistaged PSRS approach for lesions more resistant to obliteration with radiation.

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

    PubMed Central

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

    2016-01-01

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

  13. Inter-Fraction Tumor Volume Response during Lung Stereotactic Body Radiation Therapy Correlated to Patient Variables

    PubMed Central

    Ayan, Ahmet S.; Mo, Xiaokui; Williams, Terence M.; Mayr, Nina A.; Grecula, John C.; Chakravarti, Arnab; Xu-Welliver, Meng

    2016-01-01

    Purpose Analyze inter-fraction volumetric changes of lung tumors treated with stereotactic body radiation therapy (SBRT) and determine if the volume changes during treatment can be predicted and thus considered in treatment planning. Methods and Materials Kilo-voltage cone-beam CT (kV-CBCT) images obtained immediately prior to each fraction were used to monitor inter-fraction volumetric changes of 15 consecutive patients (18 lung nodules) treated with lung SBRT at our institution (45–54 Gy in 3–5 fractions) in the year of 2011–2012. Spearman's (ρ) correlation and Spearman's partial correlation analysis was performed with respect to patient/tumor and treatment characteristics. Multiple hypothesis correction was performed using False Discovery Rate (FDR) and q-values were reported. Results All tumors studied experienced volume change during treatment. Tumor increased in volume by an average of 15% and regressed by an average of 11%. The overall volume increase during treatment is contained within the planning target volume (PTV) for all tumors. Larger tumors increased in volume more than smaller tumors during treatment (q = 0.0029). The volume increase on CBCT was correlated to the treatment planning gross target volume (GTV) as well as internal target volumes (ITV) (q = 0.0085 and q = 0.0039 respectively) and could be predicted for tumors with a GTV less than 22 mL. The volume increase was correlated to the integral dose (ID) in the ITV at every fraction (q = 0.0049). The peak inter-fraction volume occurred at an earlier fraction in younger patients (q = 0.0122). Conclusions We introduced a new analysis method to follow inter-fraction tumor volume changes and determined that the observed changes during lung SBRT treatment are correlated to the initial tumor volume, integral dose (ID), and patient age. Furthermore, the volume increase during treatment of tumors less than 22mL can be predicted during treatment planning. The volume increase remained

  14. Predicting Chest Wall Pain From Lung Stereotactic Body Radiotherapy for Different Fractionation Schemes

    SciTech Connect

    Woody, Neil M.; Videtic, Gregory M.M.; Stephans, Kevin L.; Djemil, Toufik; Kim, Yongbok; Xia Ping

    2012-05-01

    Purpose: Recent studies with two fractionation schemes predicted that the volume of chest wall receiving >30 Gy (V30) correlated with chest wall pain after stereotactic body radiation therapy (SBRT) to the lung. This study developed a predictive model of chest wall pain incorporating radiobiologic effects, using clinical data from four distinct SBRT fractionation schemes. Methods and Materials: 102 SBRT patients were treated with four different fractionations: 60 Gy in three fractions, 50 Gy in five fractions, 48 Gy in four fractions, and 50 Gy in 10 fractions. To account for radiobiologic effects, a modified equivalent uniform dose (mEUD) model calculated the dose to the chest wall with volume weighting. For comparison, V30 and maximum point dose were also reported. Using univariable logistic regression, the association of radiation dose and clinical variables with chest wall pain was assessed by uncertainty coefficient (U) and C statistic (C) of receiver operator curve. The significant associations from the univariable model were verified with a multivariable model. Results: 106 lesions in 102 patients with a mean age of 72 were included, with a mean of 25.5 (range, 12-55) months of follow-up. Twenty patients reported chest wall pain at a mean time of 8.1 (95% confidence interval, 6.3-9.8) months after treatment. The mEUD models, V30, and maximum point dose were significant predictors of chest wall pain (p < 0.0005). mEUD improved prediction of chest wall pain compared with V30 (C = 0.79 vs. 0.77 and U = 0.16 vs. 0.11). The mEUD with moderate weighting (a = 5) better predicted chest wall pain than did mEUD without weighting (a = 1) (C = 0.79 vs. 0.77 and U = 0.16 vs. 0.14). Body mass index (BMI) was significantly associated with chest wall pain (p = 0.008). On multivariable analysis, mEUD and BMI remained significant predictors of chest wall pain (p = 0.0003 and 0.03, respectively). Conclusion: mEUD with moderate weighting better predicted chest wall pain than

  15. Dose-Response Modeling of the Visual Pathway Tolerance to Single-Fraction and Hypofractionated Stereotactic Radiosurgery.

    PubMed

    Hiniker, Susan M; Modlin, Leslie A; Choi, Clara Y; Atalar, Banu; Seiger, Kira; Binkley, Michael S; Harris, Jeremy P; Liao, Yaping Joyce; Fischbein, Nancy; Wang, Lei; Ho, Anthony; Lo, Anthony; Chang, Steven D; Harsh, Griffith R; Gibbs, Iris C; Hancock, Steven L; Li, Gordon; Adler, John R; Soltys, Scott G

    2016-04-01

    Patients with tumors adjacent to the optic nerves and chiasm are frequently not candidates for single-fraction stereotactic radiosurgery (SRS) due to concern for radiation-induced optic neuropathy. However, these patients have been successfully treated with hypofractionated SRS over 2-5 days, though dose constraints have not yet been well defined. We reviewed the literature on optic tolerance to radiation and constructed a dose-response model for visual pathway tolerance to SRS delivered in 1-5 fractions. We analyzed optic nerve and chiasm dose-volume histogram (DVH) data from perioptic tumors, defined as those within 3mm of the optic nerves or chiasm, treated with SRS from 2000-2013 at our institution. Tumors with subsequent local progression were excluded from the primary analysis of vision outcome. A total of 262 evaluable cases (26 with malignant and 236 with benign tumors) with visual field and clinical outcomes were analyzed. Median patient follow-up was 37 months (range: 2-142 months). The median number of fractions was 3 (1 fraction n = 47, 2 fraction n = 28, 3 fraction n = 111, 4 fraction n = 10, and 5 fraction n = 66); doses were converted to 3-fraction equivalent doses with the linear quadratic model using α/β = 2Gy prior to modeling. Optic structure dose parameters analyzed included Dmin, Dmedian, Dmean, Dmax, V30Gy, V25Gy, V20Gy, V15Gy, V10Gy, V5Gy, D50%, D10%, D5%, D1%, D1cc, D0.50cc, D0.25cc, D0.20cc, D0.10cc, D0.05cc, D0.03cc. From the plan DVHs, a maximum-likelihood parameter fitting of the probit dose-response model was performed using DVH Evaluator software. The 68% CIs, corresponding to one standard deviation, were calculated using the profile likelihood method. Of the 262 analyzed, 2 (0.8%) patients experienced common terminology criteria for adverse events grade 4 vision loss in one eye, defined as vision of 20/200 or worse in the affected eye. One of these patients had received 2 previous courses of radiotherapy to the optic structures

  16. Stereotactic Body Radiation Therapy for Primary, Recurrent, and Metastatic Tumors in the Head-and-Neck Region

    SciTech Connect

    Siddiqui, Farzan; Patel, Mehul; Khan, Mumtaz; McLean, Scott; Dragovic, Jadranka; Jin, J.-Y.; Movsas, Benjamin; Ryu, Samuel

    2009-07-15

    Purpose: To determine the feasibility, safety, and efficacy of stereotactic body radiation therapy (SBRT), also known as radiosurgery, in patients with head-and-neck cancers. Methods and Materials: Patients with pathologically proven malignant lesions in the head-and-neck region were treated using single-dose SBRT (S-SBRT) or fractionated SBRT (F-SBRT). Radiation doses were either single-fraction 13-18 Gy for S-SBRT or 36-48 Gy in five to eight fractions for F-SBRT. Response evaluation was based on clinical examinations and computed tomography/magnetic resonance imaging scans. Pre- and post-SBRT tumor dimensions were measured in three axes, and tumor volumes were calculated. Response evaluation also was performed using World Health Organization criteria. Results: Fifty-five lesions were treated in 44 patients (25 men, 19 women). There were three groups of patients: those with primary (n = 10), recurrent (n = 21), and metastatic tumors (n = 13). The predominant histologic type was squamous cell carcinoma (n = 33). The majority of lesions were treated using F-SBRT (n = 37). Based on radiographic and clinical assessment, a 77% (complete + partial response) response rate was noted. Percentage of reduction in tumor volume was 52% {+-} 38% based on follow-up scans in 24 patients. Tumor control rates at 1 year were 83.3% and 60.6% in the primary and recurrent groups, respectively. Median overall survival was 28.7, 6.7, and 5.6 months for the primary, recurrent, and metastatic groups, respectively. Radiation Therapy Oncology Group Grade 1-2 mucositis was noted in all patients treated for oropharyngeal or laryngeal lesions. Conclusions: The SBRT in single or fractionated doses offers a viable treatment option for selected patients with primary, recurrent, and metastatic head-and-neck cancers with functional preservation.

  17. Long-term Evaluation of Radiation-Induced Optic Neuropathy After Single-Fraction Stereotactic Radiosurgery

    SciTech Connect

    Leavitt, Jacqueline A.; Stafford, Scott L.; Link, Michael J.; Pollock, Bruce E.

    2013-11-01

    Purpose: To determine the long-term risk of radiation-induced optic neuropathy (RION) in patients having single-fraction stereotactic radiosurgery (SRS) for benign skull base tumors. Methods and Materials: Retrospective review of 222 patients having Gamma Knife radiosurgery for benign tumors adjacent to the anterior visual pathway (AVP) between 1991 and 1999. Excluded were patients with prior or concurrent external beam radiation therapy or SRS. One hundred twenty-nine patients (58%) had undergone previous surgery. Tumor types included confirmed World Health Organization grade 1 or presumed cavernous sinus meningioma (n=143), pituitary adenoma (n=72), and craniopharyngioma (n=7). The maximum dose to the AVP was ≤8.0 Gy (n=126), 8.1-10.0 Gy (n=39), 10.1-12.0 Gy (n=47), and >12 Gy (n=10). Results: The mean clinical and imaging follow-up periods were 83 and 123 months, respectively. One patient (0.5%) who received a maximum radiation dose of 12.8 Gy to the AVP developed unilateral blindness 18 months after SRS. The chance of RION according to the maximum radiation dose received by the AVP was 0 (95% confidence interval [CI] 0-3.6%), 0 (95% CI 0-10.7%), 0 (95% CI 0-9.0%), and 10% (95% CI 0-43.0%) for patients receiving ≤8 Gy, 8.1-10.0 Gy, 10.1-12.0 Gy, and >12 Gy, respectively. The overall risk of RION in patients receiving >8 Gy to the AVP was 1.0% (95% CI 0-6.2%). Conclusions: The risk of RION after single-fraction SRS in patients with benign skull base tumors who have no prior radiation exposure is very low if the maximum dose to the AVP is ≤12 Gy. Physicians performing single-fraction SRS should remain cautious when treating lesions adjacent to the AVP, especially when the maximum dose exceeds 10 Gy.

  18. Gemcitabine Chemotherapy and Single-Fraction Stereotactic Body Radiotherapy for Locally Advanced Pancreatic Cancer

    SciTech Connect

    Schellenberg, Devin; Goodman, Karyn A.; Lee, Florence; Chang, Stephanie; Kuo, Timothy; Quon, Andrew; Desser, Terry S.; Norton, Jeffrey; Greco, Ralph; Yang, George P.; Koong, Albert C.

    2008-11-01

    Purpose: Fractionated radiotherapy and chemotherapy for locally advanced pancreatic cancer achieves only modest local control. This prospective trial evaluated the efficacy of a single fraction of 25 Gy stereotactic body radiotherapy (SBRT) delivered between Cycle 1 and 2 of gemcitabine chemotherapy. Methods and Materials: A total of 16 patients with locally advanced, nonmetastatic, pancreatic adenocarcinoma received gemcitabine with SBRT delivered 2 weeks after completion of the first cycle. Gemcitabine was resumed 2 weeks after SBRT and was continued until progression or dose-limiting toxicity. The gross tumor volume, with a 2-3-mm margin, was treated in a single 25-Gy fraction by Cyberknife. Patients were evaluated at 4-6 weeks, 10-12 weeks, and every 3 months after SBRT. Results: All 16 patients completed SBRT. A median of four cycles (range one to nine) of chemotherapy was delivered. Three patients (19%) developed local disease progression at 14, 16, and 21 months after SBRT. The median survival was 11.4 months, with 50% of patients alive at 1 year. Patients with normal carbohydrate antigen (CA)19-9 levels either at diagnosis or after Cyberknife SBRT had longer survival (p <0.01). Acute gastrointestinal toxicity was mild, with 2 cases of Grade 2 (13%) and 1 of Grade 3 (6%) toxicity. Late gastrointestinal toxicity was more common, with five ulcers (Grade 2), one duodenal stenosis (Grade 3), and one duodenal perforation (Grade 4). A trend toward increased duodenal volumes radiated was observed in those experiencing late effects (p = 0.13). Conclusion: SBRT with gemcitabine resulted in comparable survival to conventional chemoradiotherapy and good local control. However, the rate of duodenal ulcer development was significant.

  19. Real-time 3D-surface-guided head refixation useful for fractionated stereotactic radiotherapy

    SciTech Connect

    Li Shidong; Liu Dezhi; Yin Gongjie; Zhuang Ping; Geng, Jason

    2006-02-15

    Accurate and precise head refixation in fractionated stereotactic radiotherapy has been achieved through alignment of real-time 3D-surface images with a reference surface image. The reference surface image is either a 3D optical surface image taken at simulation with the desired treatment position, or a CT/MRI-surface rendering in the treatment plan with corrections for patient motion during CT/MRI scans and partial volume effects. The real-time 3D surface images are rapidly captured by using a 3D video camera mounted on the ceiling of the treatment vault. Any facial expression such as mouth opening that affects surface shape and location can be avoided using a new facial monitoring technique. The image artifacts on the real-time surface can generally be removed by setting a threshold of jumps at the neighboring points while preserving detailed features of the surface of interest. Such a real-time surface image, registered in the treatment machine coordinate system, provides a reliable representation of the patient head position during the treatment. A fast automatic alignment between the real-time surface and the reference surface using a modified iterative-closest-point method leads to an efficient and robust surface-guided target refixation. Experimental and clinical results demonstrate the excellent efficacy of <2 min set-up time, the desired accuracy and precision of <1 mm in isocenter shifts, and <1 deg. in rotation.

  20. Treatment results of stereotactic interstitial brachytherapy for primary and metastatic brain tumors

    SciTech Connect

    Lucas, G.L.; Luxton, G.; Cohen, D.; Petrovich, Z.; Langholz, B.; Apuzzo, M.L.; Sapozink, M.D. )

    1991-08-01

    A total of 41 stereotactic interstitial brain implants in 39 patients were performed for recurrence after teletherapy (recurrence implant), or as part of initial treatment in conjunction with teletherapy (primary implant). Implanted tumors consisted of malignant gliomas (33), other primary brain tumors (3), and single metastatic lesions (3). All patients were temporarily implanted with Ir-192 using a coaxial catheter afterloading system; two patients were implanted twice. Survival post-implant for glioblastoma multiforme (GBM), 13 patients, was 10 months whether implanted primarily or for recurrence. Mean time to recurrence, measured from initiation of teletherapy to implantation, was 10 months. Twenty patients with anaplastic astrocytoma (AA) had a median survival post-implant of 23 months for primary implants (7 patients) and 11 months for recurrence implants (13 patients). Mean time to recurrence, measured from initiation of teletherapy to implantation, was 19 months. Three patients (9%) of the evaluable group required reoperation for symptomatic mass effect, all with initial diagnosis of AA. Survival for this subgroup was 14, 22, and 32 months post-implantation. Using stereotactic techniques, interstitial brachytherapy of brain tumors was technically feasible with negligible acute morbidity and mortality, and appeared to offer limited prolongation of control for a subset of patients with recurrent malignant gliomas. The role of this modality in primary treatment for malignant gliomas needs to be further defined by prospectively randomized trials.

  1. Fractionated stereotactic radiotherapy boost for gynecologic tumors: An alternative to brachytherapy?

    SciTech Connect

    Molla, Meritxell; Escude, Lluis D.; Nouet, Philippe; Popowski, Youri D.Sc.; Hidalgo, Alberto; Rouzaud, Michel; Linero, Dolores; Miralbell, Raymond . E-mail: Raymond.Miralbell@hcuge.ch

    2005-05-01

    Purpose: A brachytherapy (BT) boost to the vaginal vault is considered standard treatment for many endometrial or cervical cancers. We aimed to challenge this treatment standard by using stereotactic radiotherapy (SRT) with a linac-based micromultileaf collimator technique. Methods and Materials: Since January 2002, 16 patients with either endometrial (9) or cervical (7) cancer have been treated with a final boost to the areas at higher risk for relapse. In 14 patients, the target volume included the vaginal vault, the upper vagina, the parametria, or (if not operated) the uterus (clinical target volume [CTV]). In 2 patients with local relapse, the CTV was the tumor in the vaginal stump. Margins of 6-10 mm were added to the CTV to define the planning target volume (PTV). Hypofractionated dynamic-arc or intensity-modulated radiotherapy techniques were used. Postoperative treatment was delivered in 12 patients (2 x 7 Gy to the PTV with a 4-7-day interval between fractions). In the 4 nonoperated patients, a dose of 4 Gy/fraction in 5 fractions with 2 to 3 days' interval was delivered. Patients were immobilized in a customized vacuum body cast and optimally repositioned with an infrared-guided system developed for extracranial SRT. To further optimize daily repositioning and target immobilization, an inflated rectal balloon was used during each treatment fraction. In 10 patients, CT resimulation was performed before the last boost fraction to assess for repositioning reproducibility via CT-to-CT registration and to estimate PTV safety margins around the CTV. Finally, a comparative treatment planning study between BT and SRT was performed in 2 patients with an operated endometrial Stage I cancer. Results: No patient developed severe acute urinary or low-intestinal toxicity. No patient developed urinary late effects (>6 months). One patient with a vaginal relapse previously irradiated to the pelvic region presented with Grade 3 rectal bleeding 18 months after retreatment

  2. Esophageal Toxicity From High-Dose, Single-Fraction Paraspinal Stereotactic Radiosurgery

    SciTech Connect

    Cox, Brett W.; Jackson, Andrew; Hunt, Margie; Bilsky, Mark; Yamada, Yoshiya

    2012-08-01

    Purpose: To report the esophageal toxicity from single-fraction paraspinal stereotactic radiosurgery (SRS) and identify dosimetric and clinical risk factors for toxicity. Methods and Materials: A total of 204 spinal metastases abutting the esophagus (182 patients) were treated with high-dose single-fraction SRS during 2003-2010. Toxicity was scored using the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 4.0. Dose-volume histograms were combined to generate a comprehensive atlas of complication incidence that identifies risk factors for toxicity. Correlation of dose-volume factors with esophageal toxicity was assessed using Fisher's exact test and logistic regression. Clinical factors were correlated with toxicity. Results: The median dose to the planning treatment volume was 24 Gy. Median follow-up was 12 months (range, 3-81). There were 31 (15%) acute and 24 (12%) late esophageal toxicities. The rate of grade {>=}3 acute or late toxicity was 6.8% (14 patients). Fisher's exact test resulted in significant median splits for grade {>=}3 toxicity at V12 = 3.78 cm{sup 3} (relative risk [RR] 3.7, P=.05), V15 = 1.87 cm{sup 3} (RR 13, P=.0013), V20 = 0.11 cm{sup 3} (RR 6, P=0.01), and V22 = 0.0 cm{sup 3} (RR 13, P=.0013). The median split for D2.5 cm{sup 3} (14.02 Gy) was also a significant predictor of toxicity (RR 6; P=.01). A highly significant logistic regression model was generated on the basis of D2.5 cm{sup 3}. One hundred percent (n = 7) of grade {>=}4 toxicities were associated with radiation recall reactions after doxorubicin or gemcitabine chemotherapy or iatrogenic manipulation of the irradiated esophagus. Conclusions: High-dose, single-fraction paraspinal SRS has a low rate of grade {>=}3 esophageal toxicity. Severe esophageal toxicity is minimized with careful attention to esophageal doses during treatment planning. Iatrogenic manipulation of the irradiated esophagus and systemic agents classically associated with radiation

  3. Integration of surgery with fractionated stereotactic radiotherapy for treatment of nonfunctioning pituitary macroadenomas

    SciTech Connect

    Paek, Sun Ha; Downes, M. Beverly; Bednarz, Greg; Keane, William M.; Werner-Wasik, Maria; Curran, Walter J.; Andrews, David W. . E-mail: david.andrews@jefferson.edu

    2005-03-01

    Objective: To evaluate the efficacy of fractionated stereotactic radiotherapy (FSRT) after surgery in the management of residual or recurrent nonfunctioning pituitary adenomas with respect to tumor control and the development of complications. Methods and materials: The clinical records of patients with nonfunctioning pituitary adenomas who underwent FSRT were retrospectively analyzed. For newly diagnosed tumors, transsphenoidal surgery was performed, and, if residual tumor was identified at 3 months, FSRT was performed. If significant tumor volume persisted, transcranial surgery was performed before FSRT. We originally initiated FSRT with 2-Gy fractions to 46 Gy. We escalated the dose to 50.4 Gy thereafter. As a final modification, we dropped the daily dose to 1.8-Gy fractions delivered within 6 weeks. High-dose conformality and homogeneity was achieved with arc beam shaping and differential beam weighting. The radiographic, endocrinologic, and visual outcomes after FSRT were evaluated. Results: The 68 patients included 36 males and 32 females with an age range of 15-81 years. The median follow-up was 30 months (range, 2-82 months), and the median tumor volume was 6.2 cm{sup 3}. Of the 68 patients, 20 were treated to 46 Gy and 48 to 50-52.2 Gy. Most were treated to 50.4 Gy. Eleven patients had recurrent tumors, 54 had residual tumors, and no surgery was performed in 3 patients before FSRT. We noted no radiation-induced acute or late toxicities, except for radiation-induced optic neuropathy in 2 patients. At latest follow-up, the tumor had decreased in size in 26 patients and remained stable in 41 of the 42 remaining patients. Of the 68 patients, 4 (6%) developed hypopituitarism at 6, 11, 12, and 17 months after FSRT. Reviewing available serial Humphrey visual fields, visual fields were objectively improved in 28 patients, and remained stable in 24 patients, and worsened in 2 patients. Conclusion: The findings of this analysis support the use of surgery followed by

  4. SU-F-BRF-12: Investigating Dosimetric Effects of Inter-Fraction Deformation in Lung Cancer Stereotactic Body Radiotherapy (SBRT)

    SciTech Connect

    Jia, J; Tian, Z; Gu, X; Yan, H; Jia, X; Jiang, S

    2014-06-15

    Purpose: We studied dosimetric effects of inter-fraction deformation in lung stereotactic body radiotherapy (SBRT), in order to investigate the necessity of adaptive re-planning for lung SBRT treatments. Methods: Six lung cancer patients with different treatment fractions were retrospectively investigated. All the patients were immobilized and localized with a stereotactic body frame and were treated under cone-beam CT (CBCT) image guidance at each fraction. We calculated the actual delivered dose of the treatment plan using the up-to-date patient geometry of each fraction, and compared the dose with the intended plan dose to investigate the dosimetric effects of the inter-fraction deformation. Deformable registration was carried out between the treatment planning CT and the CBCT of each fraction to obtain deformed planning CT for more accurate dose calculations of the delivered dose. The extent of the inter-fraction deformation was also evaluated by calculating the dice similarity coefficient between the delineated structures on the planning CT and those on the deformed planning CT. Results: The average dice coefficients for PTV, spinal cord, esophagus were 0.87, 0.83 and 0.69, respectively. The volume of PTV covered by prescription dose was decreased by 23.78% on average for all fractions and all patients. For spinal cord and esophagus, the volumes covered by the constraint dose were increased by 4.57% and 3.83%. The maximum dose was also increased by 4.11% for spinal cord and 4.29% for esophagus. Conclusion: Due to inter-fraction deformation, large deterioration was found in both PTV coverage and OAR sparing, which demonstrated the needs for adaptive re-planning of lung SBRT cases to improve target coverage while reducing radiation dose to nearby normal tissues.

  5. Quality Assessment of Frameless Fractionated Stereotactic Radiotherapy Using Cone Beam Computed Tomography

    SciTech Connect

    Peng, Lee-Cheng; Kahler, Darren; Samant, Sanjiv; Li, Jonathan; Amdur, Robert; Palta, Jatinder R.; Liu, Chihray

    2010-12-01

    Purpose: A quality assessment of intracranial stereotactic radiotherapy was performed using cone beam computed tomography (CBCT). Setup errors were analyzed for two groups of patients: (1) those who were positioned using a frameless SonArray (FSA) system and immobilized with a bite plate and thermoplastic (TP) mask (the bFSA group); and (2) those who were positioned by room laser and immobilized using a TP mask (the mLAS group). Methods and Materials: A quality assurance phantom was used to study the system differences between FSA and CBCT. The quality assessment was performed using an Elekta Synergy imager (XVI) (Elekta Oncology Systems, Norcross, GA) and an On-Board Imager (OBI) (Varian Medical Systems, Palo Alto, CA) for 25 patients. For the first three fractions, and weekly thereafter, the FSA system was used for patient positioning, after which CBCT was performed to obtain setup errors. Results: (1) Phantom tests: The mean differences in the isocenter displacements for the two systems was 1.2 {+-} 0.7 mm. No significant variances were seen between the XVI and OBI units (p{approx}0.208). (2)Patient tests: The mean of the displacements between FSA and CBCT were independent of the CBCT system used; mean setup errors for the bFSA group were smaller (1.2 mm) than those of the mLAS group (3.2 mm) (p < 0.005). For the mLAS patients, the 90th percentile and the maximum rotational displacements were 3{sup o} and 5{sup o}, respectively. A 4-mm drift in setup accuracy occurred over the treatment course for 1 bFSA patient. Conclusions: System differences of less than 1 mm between CBCT and FSA were seen. Error regression was observed for the bFSA patients, using CBCT (up to 4 mm) during the treatment course. For the mLAS group, daily CBCT imaging was needed to obtain acceptable setup accuracies.

  6. Report on a randomized trial comparing two forms of immobilization of the head for fractionated stereotactic radiotherapy.

    PubMed

    Bednarz, Greg; Machtay, Mitchell; Werner-Wasik, Maria; Downes, Beverly; Bogner, Joachim; Hyslop, Terry; Galvin, James; Evans, James; Curran, Walter; Andrews, David

    2009-01-01

    Fractionated stereotactic radiotherapy (SRT) requires accurate and reproducible immobilization of the patient's head. This randomized study compared the efficacy of two commonly used forms of immobilization used for SRT. Two routinely used methods of immobilization, which differ in their approach to reproduce the head position from day to day, are the Gill-Thomas-Cosman (GTC) frame and the BrainLab thermoplastic mask. The GTC frame fixates on the patient's upper dentition and thus is in direct mechanical contact with the cranium. The BrainLab mask is a two-part masking system custom fitted to the front and back of the patient's head. After patients signed an IRB-approved informed consent form, eligible patients were randomized to either GTC frame or mask for their course of SRT. Patients were treated as per standard procedure; however, prior to each treatment a set of digital kilovolt images (ExacTrac, BrainLabAB, Germany) was taken. These images were fused with reference digitally reconstructed radiographs obtained from treatment planning CT to yield lateral, longitudinal, and vertical deviations of isocenter and head rotations about respective axes. The primary end point of the study was to compare the two systems with respect to mean and standard deviations using the distance to isocenter measure. A total of 84 patients were enrolled (69 patients evaluable with detailed positioning data). A mixed-effect linear regression and two-tiled t test were used to compare the distance measure for both the systems. There was a statistically significant (p < 0.001) difference between mean distances for these systems, suggesting that the GTC frame was more accurate. The mean 3D displacement and standard deviations were 3.17+1.95 mm for mask and 2.00+1.04 mm for frame. Both immobilization techniques were highly effective, but the GTC frame was more accurate. To optimize the accuracy of SRT, daily kilovolt image guidance is recommended with either immobilization system. PMID

  7. Report on a randomized trial comparing two forms of immobilization of the head for fractionated stereotactic radiotherapy

    SciTech Connect

    Bednarz, Greg; Machtay, Mitchell; Werner-Wasik, Maria; Downes, Beverly; Bogner, Joachim; Hyslop, Terry; Galvin, James; Evans, James; Curran, Walter Jr.; Andrews, David

    2009-01-15

    Fractionated stereotactic radiotherapy (SRT) requires accurate and reproducible immobilization of the patient's head. This randomized study compared the efficacy of two commonly used forms of immobilization used for SRT. Two routinely used methods of immobilization, which differ in their approach to reproduce the head position from day to day, are the Gill-Thomas-Cosman (GTC) frame and the BrainLab thermoplastic mask. The GTC frame fixates on the patient's upper dentition and thus is in direct mechanical contact with the cranium. The BrainLab mask is a two-part masking system custom fitted to the front and back of the patient's head. After patients signed an IRB-approved informed consent form, eligible patients were randomized to either GTC frame or mask for their course of SRT. Patients were treated as per standard procedure; however, prior to each treatment a set of digital kilovolt images (ExacTrac, BrainLabAB, Germany) was taken. These images were fused with reference digitally reconstructed radiographs obtained from treatment planning CT to yield lateral, longitudinal, and vertical deviations of isocenter and head rotations about respective axes. The primary end point of the study was to compare the two systems with respect to mean and standard deviations using the distance to isocenter measure. A total of 84 patients were enrolled (69 patients evaluable with detailed positioning data). A mixed-effect linear regression and two-tiled t test were used to compare the distance measure for both the systems. There was a statistically significant (p<0.001) difference between mean distances for these systems, suggesting that the GTC frame was more accurate. The mean 3D displacement and standard deviations were 3.17+1.95 mm for mask and 2.00+1.04 mm for frame. Both immobilization techniques were highly effective, but the GTC frame was more accurate. To optimize the accuracy of SRT, daily kilovolt image guidance is recommended with either immobilization system.

  8. Fractionated stereotactic radiotherapy in patients with benign or atypical intracranial meningioma: Long-term experience and prognostic factors

    SciTech Connect

    Milker-Zabel, Stefanie . E-mail: stefanie_milker-zabel@med.uni-heidelberg.de; Zabel, Angelika; Schulz-Ertner, Daniela; Schlegel, Wolfgang; Wannenmacher, Michael; Debus, Juergen

    2005-03-01

    Purpose: To analyze our long-term experience and prognostic factors after fractionated stereotactic radiotherapy (FSRT) in patients with benign or atypical intracranial meningioma. Methods and materials: Between January 1985 and December 2001, 317 patients with a median age of 55.7 years were treated with FSRT for intracranial meningioma. The tumor distribution was World Health Organization (WHO) Grade 1 in 48.3%, WHO Grade 2 in 8.2%, and unknown in 43.5%. Of the 317 patients, 97 underwent RT as their primary treatment, 79 underwent postoperative RT (subtotal resection in 38 and biopsy only in 41), and 141 were treated for recurrent disease. The median target volume was 33.6 cm{sup 3} (range, 1.0-412.6 cm{sup 3}). The median total dose was 57.6 Gy at 1.8 Gy/fraction five times weekly. Results: The median follow-up was 5.7 years (range, 1.2-14.3 years). The overall local tumor control rate was 93.1% (295 of 317). Of the 317 patients, 72 had a partial response on CT/MRI and 223 (70.4%) remained stable. At a median of 4.5 years after FSRT, 22 patients (6.9%) had local tumor progression on MRI. Local tumor failure was significantly greater in patients with WHO Grade 2 meningioma (p < 0.002) than in patients with WHO Grade 1 or unknown histologic features. Patients treated for recurrent meningioma showed a trend toward decreased progression-free survival compared with patients treated with primary therapy, after biopsy, or after subtotal resection (p < 0.06). Patients with a tumor volume >60 cm{sup 3} had a recurrence rate of 15.5% vs. 4.3% for those with a tumor volume of {<=}60 cm{sup 3} (p < 0.001). In 42.9% of the patients, preexisting neurologic deficits improved. Worsening of preexisting neurologic symptoms occurred in 8.2%. Eight patients developed new clinical symptoms, such as reduced vision, trigeminal neuralgia, and intermittent tinnitus located at the side of the irradiated meningioma after FSRT. Conclusion: These data have demonstrated that FSRT is an

  9. Single-Fraction Proton Beam Stereotactic Radiosurgery for Cerebral Arteriovenous Malformations

    SciTech Connect

    Hattangadi-Gluth, Jona A.; Chapman, Paul H.; Kim, Daniel; Niemierko, Andrzej; Bussière, Marc R.; Stringham, Alison; Daartz, Juliane; Ogilvy, Christopher; Loeffler, Jay S.; Shih, Helen A.

    2014-06-01

    Purpose/Objective(s): To evaluate the obliteration rate and potential adverse effects of single-fraction proton beam stereotactic radiosurgery (PSRS) in patients with cerebral arteriovenous malformations (AVMs). Methods and Materials: From 1991 to 2010, 248 consecutive patients with 254 cerebral AVMs received single-fraction PSRS at our institution. The median AVM nidus volume was 3.5 cc (range, 0.1-28.1 cc), 23% of AVMs were in critical/deep locations (basal ganglia, thalamus, or brainstem), and the most common prescription dose was 15 Gy(relative biological effectiveness [RBE]). Univariable and multivariable analyses were performed to assess factors associated with obliteration and hemorrhage. Results: At a median follow-up time of 35 months (range, 6-198 months), 64.6% of AVMs were obliterated. The median time to total obliteration was 31 months (range, 6-127 months), and the 5-year and 10-year cumulative incidence of total obliteration was 70% and 91%, respectively. On univariable analysis, smaller target volume (hazard ratio [HR] 0.78, 95% confidence interval [CI] 0.86-0.93, P<.0001), smaller treatment volume (HR 0.93, 95% CI 0.90-0.96, P<.0001), higher prescription dose (HR 1.16, 95% CI 1.07-1.26, P=.001), and higher maximum dose (HR 1.14, 95% CI 1.05-1.23, P=.002) were associated with total obliteration. Deep/critical location was also associated with decreased likelihood of obliteration (HR 0.68, 95% CI 0.47-0.98, P=.04). On multivariable analysis, critical location (adjusted HR [AHR] 0.42, 95% CI 0.27-0.65, P<.001) and smaller target volume (AHR 0.81, 95% CI 0.68-0.97, P=.02) remained associated with total obliteration. Posttreatment hemorrhage occurred in 13 cases (5-year cumulative incidence of 7%), all among patients with less than total obliteration, and 3 of these events were fatal. The most common complication was seizure, controlled with medications, both acutely (8%) and in the long term (9.1%). Conclusions: The current series is the largest

  10. SU-E-J-187: Management of Optic Organ Motion in Fractionated Stereotactic Radiotherapy

    SciTech Connect

    Manning, M; Maurer, J

    2015-06-15

    Purpose: Fractionated stereotactic radiotherapy (FSRT) for optic nerve tumors can potentially use planning target volume (PTV) expansions as small as 1–5 mm. However, the motion of the intraorbital segment of the optic nerve has not been studied. Methods: A subject with a right optic nerve sheath meningioma underwent CT simulation in three fixed gaze positions: right, left, and fixed forward at a marker. The gross tumor volume (GTV) and the organs-at-risk (OAR) were contoured on all three scans. An IMRT plan using 10 static non-coplanar fields to 50.4 Gy in 28 fractions was designed to treat the fixed-forward gazing GTV with a 1 mm PTV, then resulting coverage was evaluated for the GTV in the three positions. As an alternative, the composite structures were computed to generate the internal target volume (ITV), 1 mm expansion free-gazing PTV, and planning organat-risk volumes (PRVs) for free-gazing treatment. A comparable IMRT plan was created for the free-gazing PTV. Results: If the patient were treated using the fixed forward gaze plan looking straight, right, and left, the V100% for the GTV was 100.0%, 33.1%, and 0.1%, respectively. The volumes of the PTVs for fixed gaze and free-gazing plans were 0.79 and 2.21 cc, respectively, increasing the PTV by a factor of 2.6. The V100% for the fixed gaze and free-gazing plans were 0.85 cc and 2.8 cc, respectively increasing the treated volume by a factor of 3.3. Conclusion: Fixed gaze treatment appears to provide greater organ sparing than free-gazing. However unanticipated intrafraction right or left gaze can produce a geometric miss. Further study of optic nerve motion appears to be warranted in areas such as intrafraction optical confirmation of fixed gaze and optimized gaze directions to minimize lens and other normal organ dose in cranial radiotherapy.

  11. Stereotactic Fractionated Radiotherapy and LINAC Radiosurgery in the Treatment of Vestibular Schwannoma-Report About Both Stereotactic Methods From a Single Institution

    SciTech Connect

    Kopp, Christine; Fauser, Claudius; Mueller, Axel; Astner, Sabrina T.; Jacob, Vesna; Lumenta, Christianto; Meyer, Bernhard; Tonn, Joerg-Christian; Molls, Michael; Grosu, Anca-Ligia

    2011-08-01

    Purpose: To evaluate tumor control and side effects associated with radiosurgery (RS) and stereotactic fractionated radiotherapy (SFR) for vestibular schwannomas (VSs) in a group of patients treated at the same institution. Methods and Materials: Between May 1997 and June 2007, 115 consecutive cases of VS were treated in our department. The SFR group (47 patients), including larger tumors (maximum diameter >1.5 cm), received a total dose of 54 Gy at 1.8 Gy per fraction. The RS group (68 patients, maximum diameter <1.5 cm) received a total dose of 12 Gy at the 100% isodose. Evaluation included serial imaging tests (magnetic resonance imaging) and neurologic and functional hearing examinations. Results: The tumor control rate was 97.9% in the SFR group for a mean follow-up time of 32.1 months and 98.5% in the RS group for a mean follow-up time of 30.1 months. Hearing function was preserved after RS in 85% of the patients and after SFR in 79%. Facial and trigeminal nerve function remained mostly unaffected after SFR. After RS, new trigeminal neuropathy occurred in 9 of 68 patients (13%). Conclusions: A high tumor control rate and low number of side effects are registered after SFR and RS of VS. These results confirm that considering tumor diameter, both RS and SFR are good treatment modalities for VS.

  12. Re-irradiation with hypo-fractionated stereotactic robotic radiotherapy for salvage in adult patients with brainstem glioma

    PubMed Central

    Susheela, Sridhar P; Revannasiddaiah, Swaroop; Muzumder, Sandeep; Mallarajapatna, Govindarajan; Kallur, Kumar; Basavalingaiah, Ajaikumar S

    2013-01-01

    Purpose Brainstem glioma (BSG) is often treated with definitive irradiation. However, subsequent progression and death occur as a rule rather than the exception, after varying periods of control. The outlook of patients with post-irradiation progression is dismal, and most of these patients are treated with supportive care alone. Despite the obvious risks with an area as critical as the brainstem, it is a possibility to encounter situations wherein the patients (themselves or their associates) ask for re-irradiation, with the hope of a few extra months of life. The risk of radiation-induced brainstem toxicity may be justifiable under the strict assumption that the patients stand a chance of benefiting from re-irradiation but still may not live long enough to manifest brainstem toxicity. Methods Five adult BSG patients were treated with re-irradiation using robotic-arm stereotactic radiation therapy (SRT) between September 2009 and July 2012, primarily at the request of the concerned patient parties. Re-irradiation doses ranged from 16 to 25 Gray (Gy) delivered by robotic arm stereotactic irradiation in 2–5 fractions. Results Four out of five patients enjoyed a prolongation of survival in the order of months (three, five, six, and 14 months), which was very significant given that all patients had severe neurological compromise and poor performance status prior to re-irradiation. One patient has survived 36 months after re-irradiation and thus has lived long enough to manifest late radiation-induced brainstem toxicity. Conclusion Despite the obvious risks of brainstem toxicity associated with the use of re-irradiation for BSG, the use of fractionated stereotactic re-irradiation seems to offers prospects of additional periods of local control and augments duration of life. PMID:24171050

  13. Frameless stereotactic radiosurgery for the treatment of primary intracranial tumours in dogs.

    PubMed

    Mariani, C L; Schubert, T A; House, R A; Wong, M A; Hopkins, A L; Barnes Heller, H L; Milner, R J; Lester, N V; Lurie, D M; Rajon, D A; Friedman, W A; Bova, F J

    2015-12-01

    Stereotactic radiosurgery (SRS) is a procedure that delivers a single large radiation dose to a well-defined target. Here, we describe a frameless SRS technique suitable for intracranial targets in canines. Medical records of dogs diagnosed with a primary intracranial tumour by imaging or histopathology that underwent SRS were retrospectively reviewed. Frameless SRS was used successfully to treat tumours in 51 dogs with a variety of head sizes and shapes. Tumours diagnosed included 38 meningiomas, 4 pituitary tumours, 4 trigeminal nerve tumours, 3 gliomas, 1 histiocytic sarcoma and 1 choroid plexus tumour. Median survival time was 399 days for all tumours and for dogs with meningiomas; cause-specific survival was 493 days for both cohorts. Acute grade III central nervous system toxicity (altered mentation) occurred in two dogs. Frameless SRS resulted in survival times comparable to conventional radiation therapy, but with fewer acute adverse effects and only a single anaesthetic episode required for therapy. PMID:24007303

  14. Differences in Clinical Results After LINAC-Based Single-Dose Radiosurgery Versus Fractionated Stereotactic Radiotherapy for Patients With Vestibular Schwannomas

    SciTech Connect

    Combs, Stephanie E.; Welzel, Thomas; Schulz-Ertner, Daniela; Huber, Peter E.; Debus, Juergen

    2010-01-15

    Purpose: To evaluate the outcomes of patients with vestibular schwannoma (VS) treated with fractionated stereotactic radiotherapy (FSRT) vs. those treated with stereotactic radiosurgery (SRS). Methods and Materials: This study is based on an analysis of 200 patients with 202 VSs treated with FSRT (n = 172) or SRS (n = 30). Patients with tumor progression and/or progression of clinical symptoms were selected for treatment. In 165 out of 202 VSs (82%), RT was performed as the primary treatment for VS, and for 37 VSs (18%), RT was conducted for tumor progression after neurosurgical intervention. For patients receiving FSRT, a median total dose of 57.6 Gy was prescribed, with a median fractionation of 5 x 1.8 Gy per week. For patients who underwent SRS, a median single dose of 13 Gy was prescribed to the 80% isodose. Results: FSRT and SRS were well tolerated. Median follow-up time was 75 months. Local control was not statistically different for both groups. The probability of maintaining the pretreatment hearing level after SRS with doses of <=13 Gy was comparable to that of FSRT. The radiation dose for the SRS group (<=13 Gy vs. >13 Gy) significantly influenced hearing preservation rates (p = 0.03). In the group of patients treated with SRS doses of <=13 Gy, cranial nerve toxicity was comparable to that of the FSRT group. Conclusions: FSRT and SRS are both safe and effective alternatives for the treatment of VS. Local control rates are comparable in both groups. SRS with doses of <=13 Gy is a safe alternative to FSRT. While FSRT can be applied safely for the treatment of VSs of all sizes, SRS should be reserved for smaller lesions.

  15. Stereotactic Ablative Body Radiation Therapy for Primary Kidney Cancer: A 3-Dimensional Conformal Technique Associated With Low Rates of Early Toxicity

    SciTech Connect

    Pham, Daniel; Thompson, Ann; Kron, Tomas; Foroudi, Farshad; Kolsky, Michal Schneider; Devereux, Thomas; Lim, Andrew; Siva, Shankar

    2014-12-01

    Purpose: To describe our 3-dimensional conformal planning approaches and report early toxicities with stereotactic body radiation therapy for the management of primary renal cell carcinoma. Methods and Materials: This is an analysis of a phase 1 trial of stereotactic body radiation therapy for primary inoperable renal cell carcinoma. A dose of 42 Gy/3 fractions was prescribed to targets ≥5 cm, whereas for <5 cm 26 Gy/1 fraction was used. All patients underwent a planning 4-dimensional CT to generate a planning target volume (PTV) from a 5-mm isotropic expansion of the internal target volume. Planning required a minimum of 8 fields prescribing to the minimum isodose surrounding the PTV. Intermediate dose spillage at 50% of the prescription dose (R50%) was measured to describe the dose gradient. Early toxicity (<6 months) was scored using the Common Terminology Criteria for Adverse Events (v4.0). Results: From July 2012 to August 2013 a total of 20 patients (median age, 77 years) were recruited into a prospective clinical trial. Eleven patients underwent fractionated treatment and 9 patients a single fraction. For PTV targets <100 cm{sup 3} the median number of beams used was 8 (2 noncoplanar) to achieve an average R50% of 3.7. For PTV targets >100 cm{sup 3} the median beam number used was 10 (4 noncoplanar) for an average R50% value of 4.3. The R50% was inversely proportional to decreasing PTV volume (r=−0.62, P=.003) and increasing total beams used (r=−0.51, P=.022). Twelve of 20 patients (60%) suffered grade ≤2 early toxicity, whereas 8 of 20 patients (40%) were asymptomatic. Nausea, chest wall pain, and fatigue were the most common toxicities reported. Conclusion: A 3-dimensional conformal planning technique of 8-10 beams can be used to deliver highly tolerable stereotactic ablation to primary kidney targets with minimal early toxicities. Ongoing follow-up is currently in place to assess long-term toxicities and cancer control.

  16. Clinical evaluation of stereotactic radiation therapy for recurrent or second primary mediastinal lymph node metastases originating from non-small cell lung cancer

    PubMed Central

    Zhao, Xian-Zhi; Wu, Zhi-Qiang; Jiang, Bo; Song, Yong-Chun; Zhuang, Hong-Qing; Li, Feng-Tong; Zhao, Lu-Jun; Wang, Chang-Li; Li, Kai; Wang, Ping; Yuan, Zhi-Yong

    2015-01-01

    Aims To evaluate the safety and efficacy of stereotactic radiotherapy (SRT, both stereotactic body RT [SBRT] and fractionated stereotactic RT [FSRT]) in the treatment of patients with recurrent or second primary mediastinal lymph node metastases (R/SP-MLNMs) originating from non-small cell lung cancer (NSCLC). Methods Between 10/2006 and 7/2013, patients with R/SP-MLNMsoriginating from NSCLC were enrolled and treated with SRT at our hospital; their data was stored in prospectively-collected database. The enrolled patients were divided into Group A (without prior RT) and Group B (with prior RT). The primary end-point was overall survival (OS). The secondary end-points were the MLNM local control (LC), the time to symptom alleviation, and toxicity using the Common Terminology Criteria for Adverse Events (CTCAE v4.0). Results Thirty-three patients were treated (16 in Group A with 19 R/SP-MLNMs and 17 in Group B with 17 R/SP-MLNMs). For the entire cohort, the median OS was 25.5 months with a median follow-up of 20.9 months (range, 3.2-82). The 1-year and 3-year actuarial LC rates were 100% and 86%, respectively. Symptom alleviation was observed in 52% of patients, after a median of 6 days (range, 3-18). CTCAE v4.0 ≥ Grade 3 toxicities occurred in 5 patients (15%; all in Group B); among them, Grade 5 in 2 patients. Conclusions We recommend exercising extreme caution in using SRT for R/SP-MLNMs in patients who received prior RT (particularly to LN station 7). For patients without previous RT, SRT appears to be safe and efficacious treatment modality; prospective studies are warranted. PMID:25881546

  17. Stereotactic body radiotherapy for the treatment of medically inoperable primary renal cell carcinoma: Current evidence and future directions

    PubMed Central

    Swaminath, Anand; Chu, William

    2015-01-01

    The incidence of renal cell carcinoma (RCC) is steadily rising due to an aging population and more frequent imaging of the abdomen for other medical conditions. While surgery remains the standard of care treatment for localized disease, many patients are unfit due to their advanced age and medical comorbidities. In these patients, an active surveillance strategy or ablative therapies, including radiofrequency/microwave ablation or cryotherapy, can be offered. Such options have limitations particularly with fast growing, or larger tumors. A promising ablative therapy option to consider is stereo-tactic body radiotherapy (SBRT). SBRT refers to high dose, focally ablative radiation delivered in a short time (3–5 fractions), and is safe and effective in many other cancer sites, including lung, liver and spine. SBRT offers potential advantages in the primary kidney cancer setting due to its ablative dosing (overcoming the notion of “radio-resistance”), short treatment duration (important in an elderly population), low toxicity profile (enabling SBRT to treat larger RCCs than other ablative modalities), and non-invasiveness. To date, there is limited long-term prospective data on the outcomes of SBRT in primary RCC. However, early evidence is intriguing with respect to excellent local control and low toxicity; however, most studies vary in terms of technique and radiation dosing used. Well-designed prospective cohort studies with clearly defined and standardized techniques, dosing, follow-up, and integration of quality of life outcomes will be essential to further establish the role of SBRT in management of inoperable, localized RCC. PMID:26316914

  18. Phase I trial of panobinostat and fractionated stereotactic re-irradiation therapy for recurrent high grade gliomas.

    PubMed

    Shi, Wenyin; Palmer, Joshua D; Werner-Wasik, Maria; Andrews, David W; Evans, James J; Glass, Jon; Kim, Lyndon; Bar-Ad, Voichita; Judy, Kevin; Farrell, Christopher; Simone, Nicole; Liu, Haisong; Dicker, Adam P; Lawrence, Yaacov R

    2016-05-01

    Panobinostat is an oral HDAC inhibitor with radiosensitizing activity. We investigated the safety, tolerability and preliminary efficacy of panobinostat combined with fractionated stereotactic re-irradiation therapy (FSRT) for recurrent high grade gliomas. Patients with recurrent high grade gliomas were enrolled in a 3 + 3 dose escalation study to determine dose limiting toxicities (DLTs), maximum tolerated dose (MTD), safety, tolerability, and preliminary efficacy. FSRT was prescribed to 30-35 Gy delivered in 10 fractions. Panobinostat was administrated concurrently with radiotherapy. Of 12 evaluable patients, 8 had recurrent GBM, and 4 had recurrent anaplastic astrocytoma. There were three grade 3 or higher toxicities in each the 10 and 30 mg cohorts. In the 30 mg cohort, there was one DLT; grade 4 neutropenia. One patient developed late grade 3 radionecrosis. The median follow up was 18.8 months. The PFS6 was 67, 33, and 83 % for 10, 20, and 30 mg cohorts, respectively. The median OS was 7.8, 6.1 and 16.1 months for the 10, 20 and 30 mg cohorts, respectively. Panobinostat administrated with FSRT is well tolerated at 30 mg. A phase II trial is warranted to assess the efficacy of panobinostat plus FSRT for recurrent glioma. PMID:26821711

  19. Fractionated stereotactic radiotherapy: A method to evaluate geometric and dosimetric uncertainties using radiochromic films

    SciTech Connect

    Coscia, Gianluca; Vaccara, Elena; Corvisiero, Roberta; Cavazzani, Paolo; Ruggieri, Filippo Grillo; Taccini, Gianni

    2009-07-15

    In the authors' hospital, stereotactic radiotherapy treatments are performed with a Varian Clinac 600C equipped with a BrainLAB m3 micro-multileaf-collimator generally using the dynamic conformal arc technique. Patient immobilization during the treatment is achieved with a fixation mask supplied by BrainLAB, made with two reinforced thermoplastic sheets fitting the patient's head. With this work the authors propose a method to evaluate treatment geometric accuracy and, consequently, to determine the amount of the margin to keep in the CTV-PTV expansion during the treatment planning. The reproducibility of the isocenter position was tested by simulating a complete treatment on the anthropomorphic phantom Alderson Rando, inserting in between two phantom slices a high sensitivity Gafchromic EBT film, properly prepared and calibrated, and repeating several treatment sessions, each time removing the fixing mask and replacing the film inside the phantom. The comparison between the dose distributions measured on films and computed by TPS, after a precise image registration procedure performed by a commercial piece of software (FILMQA, 3cognition LLC (Division of ISP), Wayne, NJ), allowed the authors to measure the repositioning errors, obtaining about 0.5 mm in case of central spherical PTV and about 1.5 mm in case of peripheral irregular PTV. Moreover, an evaluation of the errors in the registration procedure was performed, giving negligible values with respect to the quantities to be measured. The above intrinsic two-dimensional estimate of treatment accuracy has to be increased for the error in the third dimension, but the 2 mm margin the authors generally use for the CTV-PTV expansion seems adequate anyway. Using the same EBT films, a dosimetric verification of the treatment planning system was done. Measured dose values are larger or smaller than the nominal ones depending on geometric irradiation conditions, but, in the authors' experimental conditions, always

  20. Fractionated stereotactic radiotherapy: a method to evaluate geometric and dosimetric uncertainties using radiochromic films.

    PubMed

    Coscia, Gianluca; Vaccara, Elena; Corvisiero, Roberta; Cavazzani, Paolo; Ruggieri, Filippo Grillo; Taccini, Gianni

    2009-07-01

    In the authors' hospital, stereotactic radiotherapy treatments are performed with a Varian Clinac 600C equipped with a BrainLAB m3 micro-multileaf-collimator generally using the dynamic conformal arc technique. Patient immobilization during the treatment is achieved with a fixation mask supplied by BrainLAB, made with two reinforced thermoplastic sheets fitting the patient's head. With this work the authors propose a method to evaluate treatment geometric accuracy and, consequently, to determine the amount of the margin to keep in the CTV-PTV expansion during the treatment planning. The reproducibility of the isocenter position was tested by simulating a complete treatment on the anthropomorphic phantom Alderson Rando, inserting in between two phantom slices a high sensitivity Gafchromic EBT film, properly prepared and calibrated, and repeating several treatment sessions, each time removing the fixing mask and replacing the film inside the phantom. The comparison between the dose distributions measured on films and computed by TPS, after a precise image registration procedure performed by a commercial piece of software (FILMQA, 3cognition LLC (Division of ISP), Wayne, NJ), allowed the authors to measure the repositioning errors, obtaining about 0.5 mm in case of central spherical PTV and about 1.5 mm in case of peripheral irregular PTV. Moreover, an evaluation of the errors in the registration procedure was performed, giving negligible values with respect to the quantities to be measured. The above intrinsic two-dimensional estimate of treatment accuracy has to be increased for the error in the third dimension, but the 2 mm margin the authors generally use for the CTV-PTV expansion seems adequate anyway. Using the same EBT films, a dosimetric verification of the treatment planning system was done. Measured dose values are larger or smaller than the nominal ones depending on geometric irradiation conditions, but, in the authors' experimental conditions, always

  1. Fractionated Stereotactic Gamma Knife Radiosurgery for Medial Temporal Lobe Epilepsy: A Case Report.

    PubMed

    Park, Hye Ran; Chung, Hyun-Tai; Lee, Sang Kun; Kim, Dong Gyu; Paek, Sun Ha

    2016-04-01

    An 18-year-old left-handed male harbored intractable medial temporal lobe epilepsy (MTLE) underwent fractionated gamma knife surgery (GKS) instead of open surgery, considering the mental retardation and diffuse cerebral dysfunction. GKS treatment parameters were: target volume, 8.8 cm(3); total marginal dose, 24 Gy in 3 fractionations at the 50% isodose line. The patient has been free from seizures since 9 months after GKS, with notable improvement in cognitive outcome. Fractionated GKS could be considered as a safe tool for seizure control and neuropsychological improvement in patients with MTLE. PMID:27122996

  2. Fractionated Stereotactic Gamma Knife Radiosurgery for Medial Temporal Lobe Epilepsy: A Case Report

    PubMed Central

    Park, Hye Ran; Chung, Hyun-Tai; Lee, Sang Kun; Kim, Dong Gyu

    2016-01-01

    An 18-year-old left-handed male harbored intractable medial temporal lobe epilepsy (MTLE) underwent fractionated gamma knife surgery (GKS) instead of open surgery, considering the mental retardation and diffuse cerebral dysfunction. GKS treatment parameters were: target volume, 8.8 cm3; total marginal dose, 24 Gy in 3 fractionations at the 50% isodose line. The patient has been free from seizures since 9 months after GKS, with notable improvement in cognitive outcome. Fractionated GKS could be considered as a safe tool for seizure control and neuropsychological improvement in patients with MTLE. PMID:27122996

  3. Primary Student Teachers' Perspectives of the Teaching of Fractions

    ERIC Educational Resources Information Center

    Bastürk, Savas

    2016-01-01

    The aim of this study was to investigate primary student teachers' perspectives of the teaching of fractions, i.e. their PCK of fractions. The research design used for the study was a descriptive survey method. As data collection instrument, we conducted a questionnaire composing of 14 open and closed-ended questions. The questionnaire was…

  4. Fractionated stereotactic radiation therapy improves cranial neuropathies in patients with skull base meningiomas: a retrospective cohort study

    PubMed Central

    2012-01-01

    Background Skull base meningiomas commonly present with cranial neuropathies. Fractionated stereotactic radiation therapy (FSRT) has been used to treat these tumors with excellent local control, but rates of improvement in cranial neuropathies have not been well defined. We review the experience at Thomas Jefferson University using FSRT in the management of these patients with a focus on symptom outcomes. Methods We identified 225 cases of skull base meningiomas treated with FSRT at Thomas Jefferson University from 1994 through 2009. The target volume was the enhancing tumor, treated to a standard prescription dose of 54 Gy. Symptoms at the time of RT were classified based on the cranial nerve affected. Logistic regression was performed to determine predictors of symptom improvement after FSRT. Results The median follow-up time was 4.4 years. In 92% of cases, patients were symptomatic at the time of RT; the most common were impaired visual field/acuity (58%) or extraocular movements (34%). After FSRT, durable improvement of at least one symptom occurred in 57% of cases, including 40% of visual acuity/visual field deficits, and 40% of diplopia/ptosis deficits. Of all symptomatic patients, 27% experienced improvement of at least one symptom within 2 months of the end of RT. Conclusions FSRT is very effective in achieving improvement of cranial neuropathies from skull base meningiomas, particularly visual symptoms. Over half of treated patients experience a durable improvement of at least one symptom, frequently within 2 months from the end of RT. PMID:23270432

  5. Dose-Volume Response Relationship for Brain Metastases Treated with Frameless Single-Fraction Linear Accelerator-Based Stereotactic Radiosurgery

    PubMed Central

    Pan, Jianmin; Yusuf, Mehran B; Dragun, Anthony; Dunlap, Neal; Guan, Timothy; Boling, Warren; Rai, Shesh; Woo, Shiao

    2016-01-01

    Background: Our aim was to identify a dose-volume response relationship for brain metastases treated with frameless stereotactic radiosurgery (SRS). Methods: We reviewed patients who underwent frameless single-fraction linear accelerator SRS for brain metastases between 2007 and 2013 from an institutional database. Proportional hazards modeling was used to identify predictors of outcome. A ratio of maximum lesion dose per mm-diameter (Gy/mm) was constructed to establish a dose-volume relationship. Results: There were 316 metastases evaluated in 121 patients (2 - 33 mm in the largest diameter). The median peripheral dose was 18.0 Gy (range: 10.0 – 24.0 Gy). Local control was 84.8% for all lesions and was affected by location, peripheral dose, maximum dose, and lesion size (p values < 0.050). A dose-volume response relationship was constructed using the maximum dose and lesion size. A unit increase in Gy/mm was associated with decreased local failure (p = 0.005). Local control of 80%, 85%, and 90% corresponded to maximum doses per millimeter of 1.67 Gy/mm, 2.86 Gy/mm, and 4.4 Gy/mm, respectively. Toxicity was uncommon and only 1.0% of lesions developed radionecrosis requiring surgery. Conclusions: For brain metastases less than 3 cm, a dose-volume response relationship exists between maximum radiosurgical dose and lesion size, which is predictive of local control. PMID:27284495

  6. Improved target volume definition for fractionated stereotactic radiotherapy in patients with intracranial meningiomas by correlation of CT, MRI, and [{sup 68}Ga]-DOTATOC-PET

    SciTech Connect

    Milker-Zabel, Stefanie . E-mail: stefanie_milker-zabel@med.uni-heidelberg.de; Zabel-du Bois, Angelika; Henze, Marcus; Huber, Peter; Schulz-Ertner, Daniela; Hoess, Angelika; Haberkorn, Uwe; Debus, Juergen

    2006-05-01

    Purpose: To evaluate the influence of {sup 68}-Ga-labeled DOTA ( )-D-Phe ({sup 1})-Tyr ({sup 3})-Octreotide positron emission tomography ([{sup 68}Ga]-DOTATOC-PET) for target definition for fractionated stereotactic radiotherapy (FSRT) as a complementary modality to computed tomography (CT) and magnetic resonance imaging (MRI). Because meningiomas show a high expression of somatostatin receptor subtype 2, somatostatin analogs such as DOTATOC offer the possibility of receptor-targeted imaging. Patients and Methods: Twenty-six patients received stereotactic CT, MRI, and [{sup 68}Ga]-DOTATOC-PET as part of their treatment planning. Histology was: World Health Organization (WHO) Grade 1 61.5%, WHO Grade 2 7.7%, WHO Grade 3 3.9%, and undetermined 26.9%. Six patients received radiotherapy as primary treatment, 2 after subtotal resection; 17 patients were treated for recurrent disease. Dynamic PET scans were acquired before radiotherapy over 60 min after intravenous injection of 156 {+-} 29 MBq [{sup 68}Ga]-DOTATOC. These PET images were imported in the planning software for FSRT. Planning target volume (PTV)-I outlined on CT and contrast-enhanced MRI was compared with PTV-II outlined on PET. PTV-III was defined with CT, MRI, and PET and was actually used for radiotherapy treatment. Results: PTV-III was smaller than PTV-I in 9 patients, the same size in 7 patients, and larger in 10 patients. Median PTV-I was 49.6 cc, median PTV-III was 57.2 cc. In all patients [{sup 68}Ga]-DOTATOC-PET delivered additional information concerning tumor extension. PTV-III was significantly modified based on DOTATOC-PET data in 19 patients. In 1 patient no tumor was exactly identified on CT/MRI but was visible on PET. Conclusion: These data demonstrate that [{sup 68}Ga]-DOTATOC-PET improves target definition for FSRT in patients with intracranial meningiomas. Radiation targeting with fused DOTATOC-PET, CT, and MRI resulted in significant alterations in target definition in 73%.

  7. Outcomes and Toxicity for Hypofractionated and Single-Fraction Image-Guided Stereotactic Radiosurgery for Sarcomas Metastasizing to the Spine

    SciTech Connect

    Folkert, Michael R.; Bilsky, Mark H.; Tom, Ashlyn K.; Oh, Jung Hun; Alektiar, Kaled M.; Laufer, Ilya; Tap, William D.; Yamada, Yoshiya

    2014-04-01

    Purpose: Conventional radiation treatment (20-40 Gy in 5-20 fractions, 2-5 Gy per fraction) for sarcoma metastatic to the spine provides subtherapeutic doses, resulting in poor durable local control (LC) (50%-77% at 1 year). Hypofractionated (HF) and/or single-fraction (SF) image-guided stereotactic radiosurgery (IG-SRS) may provide a more effective means of managing these lesions. Methods and Materials: Patients with pathologically proven high-grade sarcoma metastatic to the spine treated with HF and SF IG-SRS were included. LC and overall survival (OS) were analyzed by the use of Kaplan-Meier statistics. Univariate and multivariate analyses were performed by the use of Cox regression with competing-risks analysis; all confidence intervals are 95%. Toxicities were assessed according to Common Terminology Criteria for Adverse Events, version 4.0. Results: From May 2005 to November 11, 2012, 88 patients with 120 discrete metastases received HF (3-6 fractions; median dose, 28.5 Gy; n=52, 43.3%) or SF IG-SRS (median dose, 24 Gy; n=68, 56.7%). The median follow-up time was 12.3 months. At 12 months, LC was 87.9% (confidence interval [CI], 81.3%-94.5%), OS was 60.6% (CI, 49.6%-71.6%), and median survival was 16.9 months. SF IG-SRS demonstrated superior LC to HF IG-SRS (12-month LC of 90.8% [CI, 83%-98.6%] vs 84.1% [CI, 72.9%-95.3%] P=.007) and retained significance on multivariate analysis (P=.030, hazard ratio 0.345; CI, 0.132-0.901]. Treatment was well tolerated, with 1% acute grade 3 toxicity, 4.5% chronic grade 3 toxicity, and no grade >3 toxicities. Conclusions: In the largest series of metastatic sarcoma to the spine to date, IG-SRS provides excellent LC in the setting of an aggressive disease with low radiation sensitivity and poor prognosis. Single-fraction IG-SRS is associated with the highest rates of LC with minimal toxicity.

  8. Fractionated stereotactic radiotherapy plus bevacizumab after response to bevacizumab plus irinotecan as a rescue treatment for high-grade gliomas

    PubMed Central

    Conde-Moreno, Antonio José; García-Gómez, Raquel; Albert-Antequera, María; Almendros-Blanco, Piedad; De Las Peñas-Bataller, Ramón; González-Vidal, Verónica; López-Torrecilla, José Luis; Ferrer-Albiach, Carlos

    2015-01-01

    Aim To evaluate the possibility of implementing a new scheme of rescue treatment after relapse or progression of high-grade glioma (HGG) treated at the first-line with bevacizumab and irinotecan (BVZ+CPT11), evaluating the response and toxicity of associating BVZ and fractionated stereotactic radiotherapy (BVZ+FSRT). Materials and methods We retrospectively analysed data from 59 patients with relapse of HGG. Nine patients with HGG relapse after treatment using the Stupp protocol that were treated with BVZ+CPT11 for progression between July 2007 and August 2012, after which the response was assessed according to the Revised Assessment in Neuro-Oncology (RANO) criteria. BVZ was administered at a dose of 10 mg/kg and FSRT up to a prescribed dose of 30 Gy, 500 cGy per fraction, three days a week. The median follow-up was 38 months. Results The treatment was well-tolerated by all patients. The response after nuclear magnetic resonance imaging (MRI) at 3–6 months was progression in two patients, stable disease in four, and three patients had a partial response. The median overall survival (OS) from diagnosis until death or the last control was 36.8 months. The median progression-free survival (PFS) was 10.8 months. The results from tumour sub-group analysis indicated that the PFS was not statistically significant although it seemed that it was higher in grade-III. The OS was higher in grade-III gliomas. Conclusions The combination of BVZ+FSRT as a second-line HGG relapse rescue treatment is well-tolerated and seems to offer promising results. We believe that multi-centre prospective studies are needed to determine the long-term efficacy and toxicity of this therapeutic approach. PMID:25949228

  9. Long-Term Outcomes of Fractionated Stereotactic Radiation Therapy for Pituitary Adenomas at the BC Cancer Agency

    SciTech Connect

    Kim, Julian O.; Ma, Roy; Akagami, Ryojo; McKenzie, Michael; Johnson, Michelle; Gete, Ermias; Nichol, Alan

    2013-11-01

    Purpose: To assess the long-term disease control and toxicity outcomes of fractionated stereotactic radiation therapy (FSRT) in patients with pituitary adenomas treated at the BC Cancer Agency. Methods and Materials: To ensure a minimum of 5 years of clinical follow-up, this study identified a cohort of 76 patients treated consecutively with FSRT between 1998 and 2007 for pituitary adenomas: 71% (54/76) had nonfunctioning and 29% (22/76) had functioning adenomas (15 adrenocorticotrophic hormone-secreting, 5 growth hormone-secreting, and 2 prolactin-secreting). Surgery was used before FSRT in 96% (73/76) of patients. A median isocenter dose of 50.4 Gy was delivered in 28 fractions, with 100% of the planning target volume covered by the 90% isodose. Patients were followed up clinically by endocrinologists, ophthalmologists, and radiation oncologists. Serial magnetic resonance imaging was used to assess tumor response. Results: With a median follow-up time of 6.8 years (range, 0.6 - 13.1 years), the 7-year progression-free survival was 97.1% and disease-specific survival was 100%. Of the 2 patients with tumor progression, both had disease control after salvage surgery. Of the 22 patients with functioning adenomas, 50% (11/22) had complete and 9% (2/22) had partial responses after FSRT. Of the patients with normal pituitary function at baseline, 48% (14/29) experienced 1 or more hormone deficiencies after FSRT. Although 79% (60/76) of optic chiasms were at least partially within the planning target volumes, no patient experienced radiation-induced optic neuropathy. No patient experienced radionecrosis. No secondary malignancy occurred during follow-up. Conclusion: In this study of long-term follow-up of patients treated for pituitary adenomas, FSRT was safe and effective.

  10. Outcomes of Risk-Adapted Fractionated Stereotactic Radiotherapy for Stage I Non-Small-Cell Lung Cancer

    SciTech Connect

    Lagerwaard, Frank J. Haasbeek, Cornelis J.A.; Smit, Egbert F.; Slotman, Ben J.; Senan, S.

    2008-03-01

    Purpose: High local control rates can be achieved using stereotactic radiotherapy in Stage I non-small-cell lung cancer (NSCLC), but reports have suggested that toxicity may be of concern. We evaluated early clinical outcomes of 'risk-adapted' fractionation schemes in patients treated in a single institution. Methods and Materials: Of 206 patients with Stage I NSCLC, 81% were unfit to undergo surgery and the rest refused surgery. Pathologic confirmation of malignancy was obtained in 31% of patients. All other patients had new or growing 18F-fluorodeoxyglucose positron emission tomography positive lesions with radiologic characteristics of malignancy. Planning four-dimensional computed tomography scans were performed and fractionation schemes used (3 x 20 Gy, 5 x 12 Gy, and 8 x 7.5 Gy) were determined by T stage and risk of normal tissue toxicity. Results: Median overall survival was 34 months, with 1- and 2-year survivals of 81% and 64%, respectively. Disease-free survival (DFS) at 1 and 2 years was 83% and 68%, respectively, and DFS correlated with T stage (p = 0.002). Local failure was observed in 7 patients (3%). The crude regional failure rate was 9%; isolated regional recurrence was observed in 4%. The distant progression-free survival at 1 and 2 years was 85% and 77%, respectively. SRT was well tolerated and severe late toxicity was observed in less than 3% of patients. Conclusions: SRT is well tolerated in patients with extensive comorbidity with high local control rates and minimal toxicity. Early outcomes are not inferior to those reported for conventional radiotherapy. In view of patient convenience, such risk-adapted SRT schedules should be considered treatment of choice in patients presenting with medically inoperable Stage I NSCLC.

  11. Single-Fraction Stereotactic Body Radiation Therapy and Sequential Gemcitabine for the Treatment of Locally Advanced Pancreatic Cancer

    SciTech Connect

    Schellenberg, Devin; Kim, Jeff; Christman-Skieller, Claudia; Chun, Carlene L.; Columbo, Laurie Ann; Ford, James M.; Fisher, George A.; Kunz, Pamela L.; Van Dam, Jacques; Quon, Andrew; Desser, Terry S.; Norton, Jeffrey; Hsu, Annie; Maxim, Peter G.; Xing, Lei; Goodman, Karyn A.; Chang, Daniel T.; Koong, Albert C.

    2011-09-01

    Purpose: This Phase II trial evaluated the toxicity, local control, and overall survival in patients treated with sequential gemcitabine and linear accelerator-based single-fraction stereotactic body radiotherapy (SBRT). Methods and Materials: Twenty patients with locally advanced, nonmetastatic pancreatic adenocarcinoma were enrolled on this prospective single-institution, institutional review board-approved study. Gemcitabine was administered on Days 1, 8, and 15, and SBRT on Day 29. Gemcitabine was restarted on Day 43 and continued for 3-5 cycles. SBRT of 25 Gy in a single fraction was delivered to the internal target volume with a 2- 3-mm margin using a nine-field intensity-modulated radiotherapy technique. Respiratory gating was used to account for breathing motion. Follow-up evaluations occurred at 4-6 weeks, 10-12 weeks, and every 3 months after SBRT. Results: All patients completed SBRT and a median of five cycles of chemotherapy. Follow-up for the 2 remaining alive patients was 25.1 and 36.4 months. No acute Grade 3 or greater nonhematologic toxicity was observed. Late Grade 3 or greater toxicities occurred in 1 patient (5%) and consisted of a duodenal perforation (G4). Three patients (15%) developed ulcers (G2) that were medically managed. Overall, median survival was 11.8 months, with 1-year survival of 50% and 2-year survival of 20%. Using serial computed tomography, the freedom from local progression was 94% at 1 year. Conclusion: Linear accelerator-delivered SBRT with sequential gemcitabine resulted in excellent local control of locally advanced pancreatic cancer. Future studies will address strategies for reducing long-term duodenal toxicity associated with SBRT.

  12. A planning study investigating dual-gated volumetric arc stereotactic treatment of primary renal cell carcinoma

    SciTech Connect

    Devereux, Thomas; Pham, Daniel; Kron, Tomas; Foroudi, Farshad; Supple, Jeremy; Siva, Shankar

    2015-04-01

    This is a planning study investigating the dosimetric advantages of gated volumetric-modulated arc therapy (VMAT) to the end-exhale and end-inhale breathing phases for patients undergoing stereotactic treatment of primary renal cell carcinoma. VMAT plans were developed from the end-inhale (VMATinh) and the end-exhale (VMATexh) phases of the breathing cycle as well as a VMAT plan and 3-dimensional conformal radiation therapy plan based on an internal target volume (ITV) (VMATitv). An additional VMAT plan was created by giving the respective gated VMAT plan a 50% weighting and summing the inhale and exhale plans together to create a summed gated plan. Dose to organs at risk (OARs) as well as comparison of intermediate and low-dose conformity was evaluated. There was no difference in the volume of healthy tissue receiving the prescribed dose for the planned target volume (PTV) (CI100%) for all the VMAT plans; however, the mean volume of healthy tissue receiving 50% of the prescribed dose for the PTV (CI50%) values were 4.7 (± 0.2), 4.6 (± 0.2), and 4.7 (± 0.6) for the VMATitv, VMATinh, and VMATexh plans, respectively. The VMAT plans based on the exhale and inhale breathing phases showed a 4.8% and 2.4% reduction in dose to 30 cm{sup 3} of the small bowel, respectively, compared with that of the ITV-based VMAT plan. The summed gated VMAT plans showed a 6.2% reduction in dose to 30 cm{sup 3} of the small bowel compared with that of the VMAT plans based on the ITV. Additionally, when compared with the inhale and the exhale VMAT plans, a 4% and 1.5%, respectively, reduction was observed. Gating VMAT was able to reduce the amount of prescribed, intermediate, and integral dose to healthy tissue when compared with VMAT plans based on an ITV. When summing the inhale and exhale plans together, dose to healthy tissue and OARs was optimized. However, gating VMAT plans would take longer to treat and is a factor that needs to be considered.

  13. Radiobiological modeling analysis of the optimal fraction scheme in patients with peripheral non-small cell lung cancer undergoing stereotactic body radiotherapy.

    PubMed

    Huang, Bao-Tian; Lu, Jia-Yang; Lin, Pei-Xian; Chen, Jian-Zhou; Li, De-Rui; Chen, Chuang-Zhen

    2015-01-01

    This study aimed to determine the optimal fraction scheme (FS) in patients with small peripheral non-small cell lung cancer (NSCLC) undergoing stereotactic body radiotherapy (SBRT) with the 4 × 12 Gy scheme as the reference. CT simulation data for sixteen patients diagnosed with primary NSCLC or metastatic tumor with a single peripheral lesion ≤3 cm were used in this study. Volumetric modulated arc therapy (VMAT) plans were designed based on ten different FS of 1 × 25 Gy, 1 × 30 Gy, 1 × 34 Gy, 3 × 15 Gy, 3 × 18 Gy, 3 × 20 Gy, 4 × 12 Gy, 5 × 12 Gy, 6 × 10 Gy and 10 × 7 Gy. Five different radiobiological models were employed to predict the tumor control probability (TCP) value. Three other models were utilized to estimate the normal tissue complication probability (NTCP) value to the lung and the modified equivalent uniform dose (mEUD) value to the chest wall (CW). The 1 × 30 Gy regimen is recommended to achieve 4.2% higher TCP and slightly higher NTCP and mEUD values to the lung and CW compared with the 4 × 12 Gy schedule, respectively. This regimen also greatly shortens the treatment duration. However, the 3 × 15 Gy schedule is suggested in patients where the lung-to-tumor volume ratio is small or where the tumor is adjacent to the CW. PMID:26657569

  14. Radiobiological modeling analysis of the optimal fraction scheme in patients with peripheral non-small cell lung cancer undergoing stereotactic body radiotherapy

    PubMed Central

    Huang, Bao-Tian; Lu, Jia-Yang; Lin, Pei-Xian; Chen, Jian-Zhou; Li, De-Rui; Chen, Chuang-Zhen

    2015-01-01

    This study aimed to determine the optimal fraction scheme (FS) in patients with small peripheral non-small cell lung cancer (NSCLC) undergoing stereotactic body radiotherapy (SBRT) with the 4 × 12 Gy scheme as the reference. CT simulation data for sixteen patients diagnosed with primary NSCLC or metastatic tumor with a single peripheral lesion ≤3 cm were used in this study. Volumetric modulated arc therapy (VMAT) plans were designed based on ten different FS of 1 × 25 Gy, 1 × 30 Gy, 1 × 34 Gy, 3 × 15 Gy, 3 × 18 Gy, 3 × 20 Gy, 4 × 12 Gy, 5 × 12 Gy, 6 × 10 Gy and 10 × 7 Gy. Five different radiobiological models were employed to predict the tumor control probability (TCP) value. Three other models were utilized to estimate the normal tissue complication probability (NTCP) value to the lung and the modified equivalent uniform dose (mEUD) value to the chest wall (CW). The 1 × 30 Gy regimen is recommended to achieve 4.2% higher TCP and slightly higher NTCP and mEUD values to the lung and CW compared with the 4 × 12 Gy schedule, respectively. This regimen also greatly shortens the treatment duration. However, the 3 × 15 Gy schedule is suggested in patients where the lung-to-tumor volume ratio is small or where the tumor is adjacent to the CW. PMID:26657569

  15. Three independent one-dimensional margins for single-fraction frameless stereotactic radiosurgery brain cases using CBCT

    SciTech Connect

    Zhang, Qinghui; Chan, Maria F.; Burman, Chandra; Song, Yulin; Zhang, Mutian

    2013-12-15

    Purpose: Setting a proper margin is crucial for not only delivering the required radiation dose to a target volume, but also reducing the unnecessary radiation to the adjacent organs at risk. This study investigated the independent one-dimensional symmetric and asymmetric margins between the clinical target volume (CTV) and the planning target volume (PTV) for linac-based single-fraction frameless stereotactic radiosurgery (SRS).Methods: The authors assumed a Dirac delta function for the systematic error of a specific machine and a Gaussian function for the residual setup errors. Margin formulas were then derived in details to arrive at a suitable CTV-to-PTV margin for single-fraction frameless SRS. Such a margin ensured that the CTV would receive the prescribed dose in 95% of the patients. To validate our margin formalism, the authors retrospectively analyzed nine patients who were previously treated with noncoplanar conformal beams. Cone-beam computed tomography (CBCT) was used in the patient setup. The isocenter shifts between the CBCT and linac were measured for a Varian Trilogy linear accelerator for three months. For each plan, the authors shifted the isocenter of the plan in each direction by ±3 mm simultaneously to simulate the worst setup scenario. Subsequently, the asymptotic behavior of the CTV V{sub 80%} for each patient was studied as the setup error approached the CTV-PTV margin.Results: The authors found that the proper margin for single-fraction frameless SRS cases with brain cancer was about 3 mm for the machine investigated in this study. The isocenter shifts between the CBCT and the linac remained almost constant over a period of three months for this specific machine. This confirmed our assumption that the machine systematic error distribution could be approximated as a delta function. This definition is especially relevant to a single-fraction treatment. The prescribed dose coverage for all the patients investigated was 96.1%± 5.5% with an

  16. Hippocampal Dosimetry Predicts Neurocognitive Function Impairment After Fractionated Stereotactic Radiotherapy for Benign or Low-Grade Adult Brain Tumors

    SciTech Connect

    Gondi, Vinai; Hermann, Bruce P.; Mehta, Minesh P.; Tome, Wolfgang A.

    2012-07-15

    Purpose: To prospectively evaluate the association between hippocampal dose and long-term neurocognitive function (NCF) impairment for benign or low-grade adult brain tumors treated with fractionated stereotactic radiotherapy (FSRT). Methods and Materials: Adult patients with benign or low-grade adult brain tumors were treated with FSRT per institutional practice. No attempt was made to spare the hippocampus. NCF testing was conducted at baseline and 18 months follow-up, on a prospective clinical trial. Regression-based standardized z scores were calculated by using similar healthy control individuals evaluated at the same test-retest interval. NCF impairment was defined as a z score {<=}-1.5. After delineation of the bilateral hippocampi according to the Radiation Therapy Oncology Group contouring atlas, dose-volume histograms were generated for the left and right hippocampi and for the composite pair. Biologically equivalent doses in 2-Gy fractions (EQD{sub 2}) assuming an {alpha}/{beta} ratio of 2 Gy were computed. Fisher's exact test and binary logistic regression were used for univariate and multivariate analyses, respectively. Dose-response data were fit to a nonlinear model. Results: Of 29 patients enrolled in this trial, 18 completed both baseline and 18-month NCF testing. An EQD{sub 2} to 40% of the bilateral hippocampi >7.3 Gy was associated with impairment in Wechsler Memory Scale-III Word List (WMS-WL) delayed recall (odds ratio [OR] 19.3; p = 0.043). The association between WMS-WL delayed recall and EQD{sub 2} to 100% of the bilateral hippocampi >0.0 Gy trended to significance (OR 14.8; p = 0.068). Conclusion: EQD{sub 2} to 40% of the bilateral hippocampi greater than 7.3 Gy is associated with long-term impairment in list-learning delayed recall after FSRT for benign or low-grade adult brain tumors. Given that modern intensity-modulated radiotherapy techniques can reduce the dose to the bilateral hippocampi below this dosimetric threshold, patients

  17. Hippocampal Dosimetry Predicts Neurocognitive Function Impairment After Fractionated Stereotactic Radiotherapy for Benign or Low-Grade Adult Brain Tumors

    SciTech Connect

    Gondi, Vinai; Hermann, Bruce P.; Mehta, Minesh P.; Tome, Wolfgang A.

    2013-02-01

    Purpose: To prospectively evaluate the association between hippocampal dose and long-term neurocognitive function (NCF) impairment for benign or low-grade adult brain tumors treated with fractionated stereotactic radiotherapy (FSRT). Methods and Materials: Adult patients with benign or low-grade adult brain tumors were treated with FSRT per institutional practice. No attempt was made to spare the hippocampus. NCF testing was conducted at baseline and 18 months follow-up, on a prospective clinical trial. Regression-based standardized z scores were calculated by using similar healthy control individuals evaluated at the same test-retest interval. NCF impairment was defined as a z score {<=}-1.5. After delineation of the bilateral hippocampi according to the Radiation Therapy Oncology Group contouring atlas, dose-volume histograms were generated for the left and right hippocampi and for the composite pair. Biologically equivalent doses in 2-Gy fractions (EQD{sub 2}) assuming an {alpha}/{beta} ratio of 2 Gy were computed. Fisher's exact test and binary logistic regression were used for univariate and multivariate analyses, respectively. Dose-response data were fit to a nonlinear model. Results: Of 29 patients enrolled in this trial, 18 completed both baseline and 18-month NCF testing. An EQD{sub 2} to 40% of the bilateral hippocampi >7.3 Gy was associated with impairment in Wechsler Memory Scale-III Word List (WMS-WL) delayed recall (odds ratio [OR] 19.3; p = 0.043). The association between WMS-WL delayed recall and EQD{sub 2} to 100% of the bilateral hippocampi >0.0 Gy trended to significance (OR 14.8; p = 0.068). Conclusion: EQD{sub 2} to 40% of the bilateral hippocampi greater than 7.3 Gy is associated with long-term impairment in list-learning delayed recall after FSRT for benign or low-grade adult brain tumors. Given that modern intensity-modulated radiotherapy techniques can reduce the dose to the bilateral hippocampi below this dosimetric threshold, patients

  18. Frameless fractionated stereotactic radiation therapy of intracranial lesions: impact of cone beam CT based setup correction on dose distribution

    PubMed Central

    2013-01-01

    Background The purpose of this study was to evaluate the impact of Cone Beam CT (CBCT) based setup correction on total dose distributions in fractionated frameless stereotactic radiation therapy of intracranial lesions. Methods Ten patients with intracranial lesions treated with 30 Gy in 6 fractions were included in this study. Treatment planning was performed with Oncentra® for a SynergyS® (Elekta Ltd, Crawley, UK) linear accelerator with XVI® Cone Beam CT, and HexaPOD™ couch top. Patients were immobilized by thermoplastic masks (BrainLab, Reuther). After initial patient setup with respect to lasers, a CBCT study was acquired and registered to the planning CT (PL-CT) study. Patient positioning was corrected according to the correction values (translational, rotational) calculated by the XVI® system. Afterwards a second CBCT study was acquired and registered to the PL-CT to confirm the accuracy of the corrections. An in-house developed software was used for rigid transformation of the PL-CT to the CBCT geometry, and dose calculations for each fraction were performed on the transformed CT. The total dose distribution was achieved by back-transformation and summation of the dose distributions of each fraction. Dose distributions based on PL-CT, CBCT (laser set-up), and final CBCT were compared to assess the influence of setup inaccuracies. Results The mean displacement vector, calculated over all treatments, was reduced from (4.3 ± 1.3) mm for laser based setup to (0.5 ± 0.2) mm if CBCT corrections were applied. The mean rotational errors around the medial-lateral, superior-inferior, anterior-posterior axis were reduced from (−0.1 ± 1.4)°, (0.1 ± 1.2)° and (−0.2 ± 1.0)°, to (0.04 ± 0.4)°, (0.01 ± 0.4)° and (0.02 ± 0.3)°. As a consequence the mean deviation between planned and delivered dose in the planning target volume (PTV) could be reduced from 12.3% to 0.4% for D95 and from 5.9% to 0.1% for Dav. Maximum

  19. Stereotactic body radiotherapy (SBRT) with or without surgery for primary and metastatic liver tumors

    PubMed Central

    Kirichenko, Alexander; Gayou, Olivier; Parda, David; Kudithipudi, Vijay; Tom, Kusum; Khan, Akhtar; Abrams, Peter; Szramowski, Molly; Oliva, Jose; Monga, Dulabh; Raj, Moses; Thai, Ngoc

    2015-01-01

    Objectives We report single center experience on the outcome and toxicity of SBRT alone or in combination with surgery for inoperable primary and metastatic liver tumors between 2007 and 2014. Patients and methods Patients with 1–4 hepatic lesions and tumor diameter ≤9 cm received SBRT at 46.8Gy ± 3.7 in 4–6 fractions. The primary end point was local control with at least 6 months of radiographic followup, and secondary end points were toxicity and survival. Results Eighty-seven assessable patients (114 lesions) completed liver SBRT for hepatoma (39) or isolated metastases (48) with a median followup of 20.3 months (range 1.9–64.1). Fourteen patients underwent liver transplant with SBRT as a bridging treatment or for tumor downsizing. Eight patients completed hepatic resections in combination with planned SBRT for unresectable tumors. Two-year local control was 96% for hepatoma and 93.8% for metastases; it was 100% for lesions ≤4 cm. Two-year overall survival was 82.3% (hepatoma) and 64.3% (metastases). No incidence of grade >2 treatment toxicity was observed. Conclusion In this retrospective analysis we demonstrate that liver SBRT alone or in combination with surgery is safe and effective for the treatment of isolated inoperable hepatic malignancies and provides excellent local control rates. PMID:26776856

  20. Effect of different breathing patterns in the same patient on stereotactic ablative body radiotherapy dosimetry for primary renal cell carcinoma: A case study

    SciTech Connect

    Pham, Daniel; Kron, Tomas; Foroudi, Farshad; Siva, Shankar

    2013-10-01

    Stereotactic ablative body radiotherapy (SABR) for primary renal cell carcinoma (RCC) targets requires motion management strategies to verify dose delivery. This case study highlights the effect of a change in patient breathing amplitude on the dosimetry to organs at risk and target structures. A 73-year-old male patient was planned for receiving 26 Gy of radiation in 1 fraction of SABR for a left primary RCC. The patient was simulated with four-dimensional computed tomography (4DCT) and the tumor internal target volume (ITV) was delineated using the 4DCT maximum intensity projection. However, the initially planned treatment was abandoned at the radiation oncologist's discretion after pretreatment cone-beam CT (CBCT) motion verification identified a greater than 50% reduction in superior to inferior diaphragm motion as compared with the planning 4DCT. This patient was resimulated with respiratory coaching instructions. To assess the effect of the change in breathing on the dosimetry to the target, each plan was recalculated on the data set representing the change in breathing condition. A change from smaller to larger breathing showed a 46% loss in planning target volume (PTV) coverage, whereas a change from larger breathing to smaller breathing resulted in an 8% decrease in PTV coverage. ITV coverage was similarly reduced by 8% in both scenarios. This case study highlights the importance of tools to verify breathing motion prior to treatment delivery. 4D image guided radiation therapy verification strategies should focus on not only verifying ITV margin coverage but also the effect on the surrounding organs at risk.

  1. Dosimetric evaluation of the feasibility of stereotactic body radiotherapy for primary lung cancer with lobe-specific selective elective nodal irradiation

    PubMed Central

    Komatsu, Tetsuya; Kunieda, Etsuo; Kitahara, Tadashi; Akiba, Takeshi; Nagao, Ryuta; Fukuzawa, Tsuyoshi

    2016-01-01

    More than 10% of all patients treated with stereotactic body radiotherapy (SBRT) for primary lung cancer develop regional lymph node recurrence. We evaluated the dosimetric feasibility of SBRT with lobe-specific selective elective nodal irradiation (ENI) on dose–volume histograms. A total of 21 patients were treated with SBRT for Stage I primary lung cancer between January 2010 and June 2012 at our institution. The extents of lobe-specific selective ENI fields were determined with reference to prior surgical reports. The ENI fields included lymph node stations (LNS) 3 + 4 + 11 for the right upper lobe tumors, LNS 7 + 11 for the right middle or lower lobe tumors, LNS 5 + 11 for the left upper lobe tumors, and LNS 7 + 11 for the left lower lobe tumors. A composite plan was generated by combining the ENI plan and the SBRT plan and recalculating for biologically equivalent doses of 2 Gy per fraction, using a linear quadratic model. The V20 of the lung, D1cm3 of the spinal cord, D1cm3 and D10cm3 of the esophagus and D10cm3 of the tracheobronchial wall were evaluated. Of the 21 patients, nine patients (43%) could not fulfill the dose constraints. In all these patients, the distance between the planning target volume (PTV) of ENI (PTVeni) and the PTV of SBRT (PTVsrt) was ≤2.0 cm. Of the three patients who developed regional metastasis, two patients had isolated lymph node failure, and the lymph node metastasis was included within the ENI field. When the distance between the PTVeni and PTVsrt is >2.0 cm, SBRT with selective ENI may therefore dosimetrically feasible. PMID:26566656

  2. SU-E-T-563: Multi-Fraction Stereotactic Radiosurgery with Extend System of Gamma Knife: Treatment Verification Using Indigenously Designed Patient Simulating Multipurpose Phantom

    SciTech Connect

    Bisht, R; Kale, S; Gopishankar, N; Rath, G; Julka, P; Agarwal, D; Singh, M; Garg, A; Kumar, P; Thulkar, S; Sharma, B

    2015-06-15

    Purpose: Aim of the study is to evaluate mechanical and radiological accuracy of multi-fraction regimen and validate Gamma knife based fractionation using newly developed patient simulating multipurpose phantom. Methods: A patient simulating phantom was designed to verify fractionated treatments with extend system (ES) of Gamma Knife however it could be used to validate other radiotherapy procedures as well. The phantom has options to insert various density material plugs and mini CT/MR distortion phantoms to analyze the quality of stereotactic imaging. An additional thorax part designed to predict surface doses at various organ sites. The phantom was positioned using vacuum head cushion and patient control unit for imaging and treatment. The repositioning check tool (RCT) was used to predict phantom positioning under ES assembly. The phantom with special inserts for film in axial, coronal and sagittal plane were scanned with X-Ray CT and the acquired images were transferred to treatment planning system (LGP 10.1). The focal precession test was performed with 4mm collimator and an experimental plan of four 16mm collimator shots was prepared for treatment verification of multi-fraction regimen. The prescription dose of 5Gy per fraction was delivered in four fractions. Each fraction was analyzed using EBT3 films scanned with EPSON 10000XL Scanner. Results: The measurement of 38 RCT points showed an overall positional accuracy of 0.28mm. The mean deviation of 0.28% and 0.31 % were calculated as CT and MR image distortion respectively. The radiological focus accuracy test showed its deviation from mechanical center point of 0.22mm. The profile measurement showed close agreement between TPS planned and film measured dose. At tolerance criteria of 1%/1mm gamma index analysis showed a pass rate of > 95%. Conclusion: Our results show that the newly developed multipurpose patient simulating phantom is highly suitable for the verification of fractionated stereotactic

  3. Stereotactic Radiotherapy of Primary Lung Cancer and Other Targets: Results of Consultant Meeting of the International Atomic Energy Agency

    SciTech Connect

    Nagata, Yasushi; Wulf, Joern; Lax, Ingmar; Timmerman, Robert; Zimmermann, Frank; Stojkovski, Igor; Jeremic, Branislav

    2011-03-01

    To evaluate the current status of stereotactic body radiotherapy (SBRT) and identify both advantages and disadvantages of its use in developing countries, a meeting composed of consultants of the International Atomic Energy Agency was held in Vienna in November 2006. Owing to continuous developments in the field, the meeting was extended by subsequent discussions and correspondence (2007-2010), which led to the summary presented here. The advantages and disadvantages of SBRT expected to be encountered in developing countries were identified. The definitions, typical treatment courses, and clinical results were presented. Thereafter, minimal methodology/technology requirements for SBRT were evaluated. Finally, characteristics of SBRT for developing countries were recommended. Patients for SBRT should be carefully selected, because single high-dose radiotherapy may cause serious complications in some serial organs at risk. Clinical experiences have been reported in some populations of lung cancer, lung oligometastases, liver cancer, pancreas cancer, and kidney cancer. Despite the disadvantages expected to be experienced in developing countries, SBRT using fewer fractions may be useful in selected patients with various extracranial cancers with favorable outcome and low toxicity.

  4. The impact of abdominal compression on outcome in patients treated with stereotactic body radiotherapy for primary lung cancer

    PubMed Central

    Mampuya, Wambaka Ange; Matsuo, Yukinori; Ueki, Nami; Nakamura, Mitsuhiro; Mukumoto, Nobutaka; Nakamura, Akira; Iizuka, Yusuke; Kishi, Takahiro; Mizowaki, Takashi; Hiraoka, Masahiro

    2014-01-01

    The aim of this study was to evaluate the impact of abdominal compression (AC) on outcome in patients treated with stereotactic body radiotherapy (SBRT) for primary lung cancer. We retrospectively reviewed data for 47 patients with histologically proven non-small cell lung cancer and lung tumour motion ≥8 mm treated with SBRT. Setup error was corrected based on bony structure. The differences in overall survival (OS), local control (LC) and disease-free survival (DFS) were evaluated to compare patients treated with AC (n = 22) and without AC (n = 25). The median follow-up was 42.6 months (range, 1.4–94.6 months). The differences in the 3-year OS, LC and DFS rate between the two groups were not statistically significant (P = 0.909, 0.209 and 0.639, respectively). However, the largest difference was observed in the LC rate, which was 82.5% (95% CI, 54.9–94.0%) for patients treated without AC and 65.4% (95% CI, 40.2–82.0%) for those treated with AC. After stratifying the patients into prognostic groups based on sex and T-stage, the LC difference increased in the group with an unfavourable prognosis. The present study suggests that AC might be associated with a worse LC rate after SBRT using a bony-structure-based set-up. PMID:24801474

  5. Stereotactic hypofractionated accurate radiotherapy of the prostate (SHARP), 33.5 Gy in five fractions for localized disease: First clinical trial results

    SciTech Connect

    Madsen, Berit L. . E-mail: ronblm@vmmc.org; Hsi, R. Alex; Pham, Huong T.; Fowler, Jack F.; Esagui, Laura C.; Corman, John

    2007-03-15

    Purpose: To evaluate the feasibility and toxicity of stereotactic hypofractionated accurate radiotherapy (SHARP) for localized prostate cancer. Methods and Materials: A Phase I/II trial of SHARP performed for localized prostate cancer using 33.5 Gy in 5 fractions, calculated to be biologically equivalent to 78 Gy in 2 Gy fractions ({alpha}/{beta} ratio of 1.5 Gy). Noncoplanar conformal fields and daily stereotactic localization of implanted fiducials were used for treatment. Genitourinary (GU) and gastrointestinal (GI) toxicity were evaluated by American Urologic Association (AUA) score and Common Toxicity Criteria (CTC). Prostate-specific antigen (PSA) values and self-reported sexual function were recorded at specified follow-up intervals. Results: The study includes 40 patients. The median follow-up is 41 months (range, 21-60 months). Acute toxicity Grade 1-2 was 48.5% (GU) and 39% (GI); 1 acute Grade 3 GU toxicity. Late Grade 1-2 toxicity was 45% (GU) and 37% (GI). No late Grade 3 or higher toxicity was reported. Twenty-six patients reported potency before therapy; 6 (23%) have developed impotence. Median time to PSA nadir was 18 months with the majority of nadirs less than 1.0 ng/mL. The actuarial 48-month biochemical freedom from relapse is 70% for the American Society for Therapeutic Radiology and Oncology definition and 90% by the alternative nadir + 2 ng/mL failure definition. Conclusions: SHARP for localized prostate cancer is feasible with minimal acute or late toxicity. Dose escalation should be possible.

  6. Salvage Stereotactic Body Radiation Therapy (SBRT) for Local Failure After Primary Lung SBRT

    SciTech Connect

    Hearn, Jason W.D. Videtic, Gregory M.M.; Djemil, Toufik; Stephans, Kevin L.

    2014-10-01

    Purpose: Local failure after definitive stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer (NSCLC) is uncommon. We report the safety and efficacy of SBRT for salvage of local failure after previous SBRT with a biologically effective dose (BED) of ≥100 Gy{sub 10}. Methods and Materials: Using an institutional review board–approved lung SBRT registry, we identified all patients initially treated for early-stage NSCLC between August 2004 and January 2012 who received salvage SBRT for isolated local failure. Failure was defined radiographically and confirmed histologically unless contraindicated. All patients were treated on a Novalis/BrainLAB system using ExacTrac for image guidance, and received a BED of ≥100 Gy{sub 10} for each SBRT course. Tumor motion control involved a Bodyfix vacuum system for immobilization along with abdominal compression. Results: Of 436 patients treated from August 2004 through January 2012, we identified 22 patients with isolated local failure, 10 of whom received SBRT for salvage. The median length of follow-up was 13.8 months from salvage SBRT (range 5.3-43.5 months). Median tumor size was 3.4 cm (range 1.7-4.8 cm). Two of the 10 lesions were “central” by proximity to the mediastinum, but were outside the zone of the proximal bronchial tree. Since completing salvage, 3 patients are alive and without evidence of disease. A fourth patient died of medical comorbidities without recurrence 13.0 months after salvage SBRT. Two patients developed distant disease only. Four patients had local failure. Toxicity included grade 1-2 fatigue (3 patients) and grade 1-2 chest wall pain (5 patients). There was no grade 3-5 toxicity. Conclusions: Repeat SBRT with a BED of ≥100 Gy{sub 10} after local failure in patients with early-stage medically inoperable NSCLC was well tolerated in this series and may represent a viable salvage strategy in select patients with peripheral tumors ≤5 cm.

  7. Minimal Inter-Fractional Fiducial Migration during Image-Guided Lung Stereotactic Body Radiotherapy Using SuperLock Nitinol Coil Fiducial Markers

    PubMed Central

    Rong, Yi; Bazan, Jose G.; Sekhon, Ashley; Haglund, Karl; Xu-Welliver, Meng; Williams, Terence

    2015-01-01

    Objectives Stereotactic body radiotherapy (SBRT) is being increasingly used for the treatment of patients with lung cancer or lung metastasis who are medically unfit to undergo resection. In order to improve accuracy and confidence in targeting tumors, many centers rely on fiducial implantation. We evaluated the migration of a novel fiducial marker specifically designed for lung tissue implanted via electromagnetic navigation bronchoscopy (ENB). Methods We retrospectively quantified the individual and group migrations of SuperLock nitinol coil fiducials for 15 patients receiving lung stereotactic body radiotherapy (SBRT), in order to evaluate the reliability of using these fiducials as a target surrogate for cases where tumors cannot be clearly delineated on cone beam CTs (CBCTs). For each fraction, we compared the individual and group migrations of the fiducials between the planning CT and the acquired CBCT. The group migration was defined as the distance between the centroids of the fiducial group and GTV. Results A total of 16 lung targets were included in our study for these 15 patients (one patient with two targets). Of 55 fiducials placed, we observed a 100% retention rate. The mean individual migration was 1.87 mm (range, 0.63–5.25 mm) with a standard deviation of 1.26 mm. The mean group migration was 1.94 mm (range, 0.03–6.19 mm) with a standard deviation of 1.45 mm. Overall, there was minimal change in the relative locations of the markers with respect to each other, as well as to the target. Conclusions We found that the SuperLock nitinol coil fiducial marker positions are stable throughout the radiation treatment, and can be used as a reliable surrogate to target, and to avoid geometric misses during gated treatments. PMID:26158847

  8. A Phase I Dose-Escalation Study of Fractionated Stereotactic Radiosurgery in Combination With Gefitinib in Patients With Recurrent Malignant Gliomas

    SciTech Connect

    Schwer, Amanda L.; Damek, Denise M.; Kavanagh, Brian D.; Gaspar, Laurie E.; Lillehei, Kevin; Stuhr, Kelly; Chen Changhu

    2008-03-15

    Purpose: To determine the maximum tolerated dose (MTD) of fractionated stereotactic radiosurgery (SRS) with gefitinib in patients with recurrent malignant gliomas. Methods and Materials: A Phase I clinical trial was performed. Eligible patients had pathologically proved recurrent anaplastic astrocytoma or glioblastoma. Patients started gefitinib (250 mg/day) 7 days before SRS and continued for 1 year or until disease progression. SRS was delivered in three fractions over 3 days. The planning target volume (PTV) was the T1-weighted MRI postcontrast enhancing lesion + 2 mm. The first cohort received an SRS dose of 18 Gy, and subsequent cohorts received higher doses up to the maximum dose of 36 Gy. Dose-limiting toxicity (DLT) was any Grade 3 toxicity. The MTD was exceeded if 2 of 6 patients in a cohort experienced DLT. Results: Characteristics of the 15 patients enrolled were: 9 men, 6 women; median age, 47 years (range, 23-65 years); 11 glioblastoma, 4 AA; median prior RT dose, 60 Gy (range, 54-61.2 Gy); median interval since RT, 12 months (range, 3-57 months); median PTV, 41 cc (range, 12-151 cc). Median follow-up time was 7 months (range, 2-28 months). Median time on gefitinib was 5 months (range, 2-12 months). No patient experienced a DLT, and the SRS dose was escalated from 18 to 36 Gy. Grade 1-2 gefitinib-related dermatitis and diarrhea were common (10 and 7 patients, respectively). Conclusion: Fractionated SRS to a dose of 36 Gy in three fractions is well tolerated with gefitinib at daily dose of 250 mg. Further studies of SRS and novel molecular targeted agents are warranted in this challenging clinical setting.

  9. Image-guided stereotactic radiotherapy in 4 dogs with intracranial neoplasia.

    PubMed

    Moon, Alaina Burkard; Heller, Heidi Barnes; Forrest, Lisa

    2016-05-01

    The purpose of this study was to describe the use, and side effects, of a novel stereotactic radiotherapy protocol using TomoTherapy(®) in 4 dogs with confirmed or suspected primary extra-axial intracranial neoplasia. Three fractions of 8 Gy were prescribed. Acute side effects were noted in 1 dog; no late effects were noted. PMID:27152041

  10. Symptomatic Outcomes in Relation to Tumor Expansion After Fractionated Stereotactic Radiation Therapy for Vestibular Schwannomas: Single-Institutional Long-Term Experience

    SciTech Connect

    Aoyama, Hidefumi; Onodera, Shunsuke; Takeichi, Norihito; Onimaru, Rikiya; Terasaka, Shunsuke; Sawamura, Yutaka; Shirato, Hiroki

    2013-02-01

    Purpose: The effect of transient tumor expansion after conventionally fractionated stereotactic radiation therapy (SRT) on the symptomatic outcomes is not well-known. Methods and Materials: This study enrolled 201 consecutive patients who received SRT for vestibular schwannoma. A conventional fractionation schedule was applied in 194 patients (97%), and 142 (71%) received a total dose of 50 Gy. The median follow-up time was 72 months. Results: The maximum diameter was 9 mm or less in 13 patients, 10-19 mm in 79 patients, 20-29 mm in 87 patients, and 30 mm or greater in 22 patients. At presentation, tumor size of 20 mm or greater was significantly associated with loss of serviceable hearing and trigeminal neuropathy. After SRT, tumor expansion was observed in 42 patients (21%). By tumor size, tumor expansion was observed in 0%, 11.4%, 25.6%, and 50% of patients with tumors of 9 mm or less, 10-19 mm, 20-29 mm, and 30 mm or greater, respectively, in diameter. The tumor expansion was significantly associated with an increased risk of hydrocephalus requiring shunt placement (P=.004), loss of serviceable hearing (P=.0064), and worsening of facial (P<.0001) and trigeminal nerve (P<.0001) functions. Spontaneous tumor shrinkage was observed in 29 of those 42 patients, mostly within 2 years after the expansion, and the majority of the worsened symptoms except for hearing resolved once the tumor had shrunk. As a result, salvage surgical resection for symptomatic relief was required in only 5% of patients. Conclusions: Fractionated SRT could be safely applied even for medium- to large-sized ({>=}20 mm) tumors. However, greater knowledge of the risks and consequences, including transient symptomatic worsening, and the time span of expansion will be required for the follow-up of patients after SRT to avoid unnecessary surgical intervention.

  11. Stereotactic Radiosurgery for Glioblastoma.

    PubMed

    Redmond, Kristin J; Mehta, Minesh

    2015-01-01

    Glioblastoma (GBM) is the most common primary malignant brain tumor in adults and one of the most aggressive of all human cancers. GBM tumors are highly infiltrative and relatively resistant to conventional therapies. Aggressive management of GBM using a combination of surgical resection, followed by fractionated radiotherapy and chemotherapy has been shown to improve overall survival; however, GBM tumors recur in the majority of patients and the disease is most often fatal. There is a need to develop new treatment regimens and technological innovations to improve the overall survival of GBM patients. The role of stereotactic radiosurgery (SRS) for the treatment of GBM has been explored and is controversial. SRS utilizes highly precise radiation techniques to allow dose escalation and delivery of ablative radiation doses to the tumor while minimizing dose to the adjacent normal structures. In some studies, SRS with concurrent chemotherapy has shown improved local control with acceptable toxicities in select GBM patients. However, because GBM is a highly infiltrative disease, skeptics argue that local therapies, such as SRS, do not improve overall survival. The purpose of this article is to review the literature regarding SRS in both newly diagnosed and recurrent GBM, to describe SRS techniques, potential eligible SRS candidates, and treatment-related toxicities. In addition, this article will propose promising areas for future research for SRS in the treatment of GBM. PMID:26848407

  12. Single-fraction versus multifraction spinal stereotactic radiosurgery for spinal metastases from renal cell carcinoma: secondary analysis of Phase I/II trials.

    PubMed

    Ghia, Amol J; Chang, Eric L; Bishop, Andrew J; Pan, Hubert Y; Boehling, Nicholas S; Amini, Behrang; Allen, Pamela K; Li, Jing; Rhines, Laurence D; Tannir, Nizar M; Tatsui, Claudio E; Brown, Paul D; Yang, James N

    2016-05-01

    OBJECTIVE The objective of this study was to compare fractionation schemes and outcomes of patients with renal cell carcinoma (RCC) treated in institutional prospective spinal stereotactic radiosurgery (SSRS) trials who did not previously undergo radiation treatment at the site of the SSRS. METHODS Patients enrolled in 2 separate institutional prospective protocols and treated with SSRS between 2002 and 2011 were included. A secondary analysis was performed on patients with previously nonirradiated RCC spinal metastases treated with either single-fraction (SF) or multifraction (MF) SSRS. RESULTS SSRS was performed in 47 spinal sites on 43 patients. The median age of the patients was 62 years (range 38-75 years). The most common histological subtype was clear cell (n = 30). Fifteen sites underwent surgery prior to the SSRS, with laminectomy the most common procedure performed (n = 10). All SF SSRS was delivered to a dose of 24 Gy (n = 21) while MF regiments were either 27 Gy in 3 fractions (n = 20) or 30 Gy in 5 fractions (n = 6). The median overall survival duration for the entire cohort was 22.8 months. The median local control (LC) for the entire cohort was 80.6 months with 1-year and 2-year actuarial LC rates of 82% and 68%, respectively. Single-fraction SSRS correlated with improved 1- and 2-year actuarial LC relative to MF SSRS (95% vs 71% and 86% vs 55%, respectively; p = 0.009). On competing risk analysis, SF SSRS showed superior LC to MF SSRS (subhazard ratio [SHR] 6.57, p = 0.014). On multivariate analysis for LC with tumor volume (p = 0.272), number of treated levels (p = 0.819), gross tumor volume (GTV) coverage (p = 0.225), and GTV minimum point dose (p = 0.97) as covariates, MF SSRS remained inferior to SF SSRS (SHR 5.26, p = 0.033) CONCLUSIONS SSRS offers durable LC for spinal metastases from RCC. Single-fraction SSRS is associated with improved LC over MF SSRS for previously nonirradiated RCC spinal metastases. PMID:26799117

  13. Clinical Outcomes of Biological Effective Dose-Based Fractionated Stereotactic Radiation Therapy for Metastatic Brain Tumors From Non-Small Cell Lung Cancer

    SciTech Connect

    Matsuyama, Tomohiko; Kogo, Kasei; Oya, Natsuo

    2013-03-15

    Purpose: To evaluate the efficacy and toxicity of fractionated stereotactic radiation therapy (FSRT) based on biological effective dose (BED), a novel approach to deliver a fixed BED irrespective of dose fractionation, for brain metastases from non-small cell lung cancer (NSCLC). Methods and Materials: Between March 2005 and March 2009 we treated 299 patients with 1 to 5 lesions from NSCLC (573 total brain metastases) with FSRT using Novalis. The dose fractionation schedules were individually determined to deliver a peripheral BED10 (α/β ratio = 10) of approximately 80 Gy{sub 10}. The median number of fractions was 3 (range, 2-10), the median peripheral BED10 was 83.2 Gy (range, 19.1-89.6 Gy). Patients were followed up with magnetic resonance imaging (MRI) studies performed at 1- to 2-month intervals. The local tumor control rate and overall local progression-free and intracranial relapse-free survival were calculated by the Kaplan-Meier method. Results: Local control rates for all 573 lesions at 6 and 12 months were 96.3% and 94.5%, respectively. By multivariate analysis the tumor diameter was the only factor predictive of the local control rate (P=.001). The median overall survival, local progression-free survival, and intracranial relapse-free survival were 17.1, 14.9, and 4.4 months, respectively. The overall survival, local progression-free survival, and intracranial relapse-free survival rates at 6 and 12 months were 78.5% and 63.3%, 74.3% and 57.8%, and 41.0% and 21.8%, respectively. Six patients (2%) manifested progressive radiation injury to the brain even during therapy with corticosteroids; they underwent hyperbaric oxygen therapy, and follow-up MRI showed improvement. Conclusions: This study showed that BED-based FSRT for brain metastases from NSCLC is a promising strategy that may yield excellent outcomes with acceptable toxicity. Criteria must be established to determine the optimal dose fractionation for individual patients.

  14. On-Board Imaging Validation of Optically Guided Stereotactic Radiosurgery Positioning System for Conventionally Fractionated Radiotherapy for Paranasal Sinus and Skull Base Cancer

    SciTech Connect

    Maxim, Peter G.; Loo, Billy W.; Murphy, James D.; Chu, Karen P.M.; Hsu, Annie; Le, Quynh-Thu

    2011-11-15

    Purpose: To evaluate the positioning accuracy of an optical positioning system for stereotactic radiosurgery in a pilot experience of optically guided, conventionally fractionated, radiotherapy for paranasal sinus and skull base tumors. Methods and Materials: Before each daily radiotherapy session, the positioning of 28 patients was set up using an optical positioning system. After this initial setup, the patients underwent standard on-board imaging that included daily orthogonal kilovoltage images and weekly cone beam computed tomography scans. Daily translational shifts were made after comparing the on-board images with the treatment planning computed tomography scans. These daily translational shifts represented the daily positional error in the optical tracking system and were recorded during the treatment course. For 13 patients treated with smaller fields, a three-degree of freedom (3DOF) head positioner was used for more accurate setup. Results: The mean positional error for the optically guided system in patients with and without the 3DOF head positioner was 1.4 {+-} 1.1 mm and 3.9 {+-} 1.6 mm, respectively (p <.0001). The mean positional error drifted 0.11 mm/wk upward during the treatment course for patients using the 3DOF head positioner (p = .057). No positional drift was observed in the patients without the 3DOF head positioner. Conclusion: Our initial clinical experience with optically guided head-and-neck fractionated radiotherapy was promising and demonstrated clinical feasibility. The optically guided setup was especially useful when used in conjunction with the 3DOF head positioner and when it was recalibrated to the shifts using the weekly portal images.

  15. SU-E-T-132: Dosimetric Impact of Positioning Errors in Hypo-Fractionated Cranial Radiation Therapy Using Frameless Stereotactic BrainLAB System

    SciTech Connect

    Keeling, V; Jin, H; Ali, I; Ahmad, S

    2014-06-01

    Purpose: To determine dosimetric impact of positioning errors in the stereotactic hypo-fractionated treatment of intracranial lesions using 3Dtransaltional and 3D-rotational corrections (6D) frameless BrainLAB ExacTrac X-Ray system. Methods: 20 cranial lesions, treated in 3 or 5 fractions, were selected. An infrared (IR) optical positioning system was employed for initial patient setup followed by stereoscopic kV X-ray radiographs for position verification. 6D-translational and rotational shifts were determined to correct patient position. If these shifts were above tolerance (0.7 mm translational and 1° rotational), corrections were applied and another set of X-rays was taken to verify patient position. Dosimetric impact (D95, Dmin, Dmax, and Dmean of planning target volume (PTV) compared to original plans) of positioning errors for initial IR setup (XC: Xray Correction) and post-correction (XV: X-ray Verification) was determined in a treatment planning system using a method proposed by Yue et al. (Med. Phys. 33, 21-31 (2006)) with 3D-translational errors only and 6D-translational and rotational errors. Results: Absolute mean translational errors (±standard deviation) for total 92 fractions (XC/XV) were 0.79±0.88/0.19±0.15 mm (lateral), 1.66±1.71/0.18 ±0.16 mm (longitudinal), 1.95±1.18/0.15±0.14 mm (vertical) and rotational errors were 0.61±0.47/0.17±0.15° (pitch), 0.55±0.49/0.16±0.24° (roll), and 0.68±0.73/0.16±0.15° (yaw). The average changes (loss of coverage) in D95, Dmin, Dmax, and Dmean were 4.5±7.3/0.1±0.2%, 17.8±22.5/1.1±2.5%, 0.4±1.4/0.1±0.3%, and 0.9±1.7/0.0±0.1% using 6Dshifts and 3.1±5.5/0.0±0.1%, 14.2±20.3/0.8±1.7%, 0.0±1.2/0.1±0.3%, and 0.7±1.4/0.0±0.1% using 3D-translational shifts only. The setup corrections (XC-XV) improved the PTV coverage by 4.4±7.3% (D95) and 16.7±23.5% (Dmin) using 6D adjustment. Strong correlations were observed between translation errors and deviations in dose coverage for XC. Conclusion

  16. Alpha/Beta Ratio for Normal Lung Tissue as Estimated From Lung Cancer Patients Treated With Stereotactic Body and Conventionally Fractionated Radiation Therapy

    SciTech Connect

    Scheenstra, Alize E.H.; Rossi, Maddalena M.G.; Belderbos, José S.A.; Damen, Eugène M.F.; Lebesque, Joos V.; Sonke, Jan-Jakob

    2014-01-01

    Purpose: To estimate the α/β ratio for which the dose-dependent lung perfusion reductions for stereotactic body radiation therapy (SBRT) and conventionally fractionated radiation therapy (CFRT) are biologically equivalent. Methods and Materials: The relations between local dose and perfusion reduction 4 months after treatment in lung cancer patients treated with SBRT and CFRT were scaled according to the linear-quadratic model using α/β ratios from 0 Gy to ∞ Gy. To test for which α/β ratio both treatments have equal biological effect, a 5-parameter logistic model was optimized for both dose–effect relationships simultaneously. Beside the α/β ratio, the other 4 parameters were d{sub 50}, the steepness parameter k, and 2 parameters (M{sub SBRT} and M{sub CFRT}) representing the maximal perfusion reduction at high doses for SBRT and CFRT, respectively. Results: The optimal fitted model resulted in an α/β ratio of 1.3 Gy (0.5-2.1 Gy), M{sub SBRT} = 42.6% (40.4%-44.9%), M{sub CFRT} = 66.9% (61.6%-72.1%), d{sub 50} = 35.4 Gy (31.5-9.2 Gy), and k = 2.0 (1.7-2.3). Conclusions: An equal reduction of lung perfusion in lung cancer was observed in SBRT and CFRT if local doses were converted by the linear-quadratic model with an α/β ratio equal to 1.3 Gy (0.5-2.1 Gy)

  17. Stereotactic body radiotherapy for patients with oligometastases from colorectal cancer: risk-adapted dose prescription with a maximum dose of 83–100 Gy in five fractions

    PubMed Central

    Takeda, Atsuya; Sanuki, Naoko; Tsurugai, Yuichiro; Oku, Yohei; Aoki, Yousuke

    2016-01-01

    We previously reported that the local control of pulmonary metastases from colorectal cancer (CRC) following stereotactic body radiotherapy (SBRT) with moderate prescription dose was relatively worse. We investigated the treatment outcomes and toxicities of patients with oligometastases from CRC treated by SBRT using risk-adapted, very high- and convergent-dose regimens. Among patients referred for SBRT from August 2011 to January 2015, those patients were extracted who had liver or pulmonary metastases from CRC, and they were treated with a total dose of 50–60 Gy in five fractions prescribed to the 60% isodose line of the maximum dose covering the surface of the planning target volume. Concurrent administration of chemotherapy was not admitted during SBRT, while neoadjuvant or adjuvant chemotherapy was allowed. A total of 21 patients (12 liver, 9 lung) with 28 oligometastases were evaluated. The median follow-up duration was 27.5 months (range: 6.5–43.3 months). Four patients were treated with SBRT as a series of initial treatments, and 17 patients were treated after recurrent oligometastases. The local control rates at 1 and 2 years from the start of SBRT were 100%. The disease-free and actuarial overall survival rates were 62% and 55%, and 79% and 79%, respectively. No severe toxicities (≥grade 3) occurred during follow-up. The outcomes following high-dose SBRT were excellent. This treatment can provide an alternative to the surgical resection of oligometastases from CRC. Prospective studies are needed to validate the effectiveness of SBRT. PMID:26983981

  18. Tumor Shrinkage Assessed by Volumetric MRI in Long-Term Follow-Up After Fractionated Stereotactic Radiotherapy of Nonfunctioning Pituitary Adenoma

    SciTech Connect

    Kopp, Christine; Theodorou, Marilena; Poullos, Nektarios; Jacob, Vesna; Astner, Sabrina T.; Molls, Michael; Grosu, Anca-Ligia

    2012-03-01

    Purpose: To evaluate tumor control and side effects associated with fractionated stereotactic radiotherapy (FSRT) in the management of residual or recurrent nonfunctioning pituitary adenomas (NFPAs). Methods and Materials: We assessed exact tumor volume shrinkage in 16 patients with NFPA after FSRT. All patients had previously undergone surgery. Gross tumor volume (GTV) was outlined on contrast-enhanced magnetic resonance imaging (MRI) before and median 63 months (range, 28-100 months) after FSRT. MRI was performed as an axial three-dimensional gradient echo T1-weighted sequence at 1.6-mm slice thickness without gap (3D MRI). Results: Mean tumor size of all 16 pituitary adenomas before treatment was 7.4 mL (3.3-18.9 mL). We found shrinkage of the treated pituitary adenoma in all patients. Within a median follow-up of 63 months (28-100 months) an absolute mean volume reduction of 3.8 mL (0.9-12.4 mL) was seen. The mean relative size reduction compared with the volume before radiotherapy was 51% (22%-95%). Shrinkage measured by 3D MRI was greater at longer time intervals after radiotherapy. A strong negative correlation between the initial tumor volume and the absolute volume reduction after FSRT was found. There was no correlation between tumor size reduction and patient age, sex, or number of previous surgeries. Conclusions: By using 3D MRI in all patients undergoing FSRT of an NFPA, tumor shrinkage is detected. Our data demonstrate that volumetric assessment based on 3D MRI adds additional information to routinely used radiological response measurements. After FSRT a mean relative size reduction of 51% can be expected within 5 years.

  19. [Stereotactic radiotherapy in brain metastases].

    PubMed

    Dhermain, F; Reyns, N; Colin, P; Métellus, P; Mornex, F; Noël, G

    2015-02-01

    Stereotactic radiotherapy of brain metastases is increasingly proposed after polydisciplinary debates among experts. Its definition and modalities of prescription, indications and clinical interest regarding the balance between efficacy versus toxicity need to be discussed. Stereotactic radiotherapy is a 'high precision' irradiation technique (within 1mm), using different machines (with invasive contention or frameless, photons X or gamma) delivering high doses (4 to 25Gy) in a limited number of fractions (usually 1 to 5, ten maximum) with a high dose gradient. Dose prescription will depend on materials, dose constraints to organs at risk varying with fractionation. Stereotactic radiotherapy may be proposed: (1) in combination with whole brain radiotherapy with the goal of increasing (modestly) overall survival of patients with a good performance status, 1 to 3 brain metastases and a controlled extracranial disease; (2) for recurrence of 1-3 brain metastases after whole brain radiotherapy; (3) after complete resection of a large and/or symptomatic brain metastases; (4) after diagnosis of 3-5 asymptomatic new or progressing brain metastases during systemic therapy, with the aim of delaying whole brain radiotherapy (avoiding its potential neurotoxicity) and maintaining a high focal control rate. Only a strict follow-up with clinical and MRI every 3 months will permit to deliver iterative stereotactic radiotherapies without jeopardizing survival. Simultaneous delivering of stereotactic radiotherapy with targeted medicines should be carefully discussed. PMID:25640215

  20. Descriptive Analysis of Oligometastatic Lesions Treated With Curative-Intent Stereotactic Body Radiotherapy

    SciTech Connect

    Milano, Michael T. Katz, Alan W.; Schell, Michael C.; Philip, Abraham; Okunieff, Paul

    2008-12-01

    Purpose: To characterize oligometastases in patients enrolled on two prospective pilot studies, treating oligometastases with hypofractionated stereotactic body radiotherapy and stereotactic radiosurgery to cranial lesions. Methods and Materials: We describe the characteristics and local control (LC) of 293 lesions in 121 patients with five or fewer metastases treated with stereotactic body radiation and/or cranial stereotactic radiosurgery. For each lesion, the primary cancer site, tumor histology, site of metastasis, gross tumor volume, and prescribed dose were ascertained. The prescribed dose is expressed by the biologically effective dose in 2-Gy fractions (BED2), calculated using the linear quadratic model, assuming an {alpha}/{beta} ratio of 10. Results: Lung lesions were significantly smaller than other lesions in our cohort, whereas liver lesions were significantly larger, possibly reflecting a detection and/or referral bias. The 2-year and 4-year tumor LC rates were 77% and 73% respectively. A larger gross tumor volume was significantly (p < 0.0001) correlated with worse lesion LC. Lesions originating from primary pancreatic, biliary or liver cancer exhibited significantly poorer LC, as did lesions from colorectal cancer. Lesions from breast cancer were better controlled. A higher BED2 did not correlate with improved tumor control. Conclusions: Stereotactic body radiation to aggressively treat oligometastatic lesions results in good local tumor control. Bulkier lesions are more difficult to control and may benefit from dose escalation.

  1. Cost-Effectiveness Analysis of Single Fraction of Stereotactic Body Radiation Therapy Compared With Single Fraction of External Beam Radiation Therapy for Palliation of Vertebral Bone Metastases

    SciTech Connect

    Kim, Hayeon; Rajagopalan, Malolan S.; Beriwal, Sushil; Huq, M. Saiful; Smith, Kenneth J.

    2015-03-01

    Purpose: Stereotactic body radiation therapy (SBRT) has been proposed for the palliation of painful vertebral bone metastases because higher radiation doses may result in superior and more durable pain control. A phase III clinical trial (Radiation Therapy Oncology Group 0631) comparing single fraction SBRT with single fraction external beam radiation therapy (EBRT) in palliative treatment of painful vertebral bone metastases is now ongoing. We performed a cost-effectiveness analysis to compare these strategies. Methods and Materials: A Markov model, using a 1-month cycle over a lifetime horizon, was developed to compare the cost-effectiveness of SBRT (16 or 18 Gy in 1 fraction) with that of 8 Gy in 1 fraction of EBRT. Transition probabilities, quality of life utilities, and costs associated with SBRT and EBRT were captured in the model. Costs were based on Medicare reimbursement in 2014. Strategies were compared using the incremental cost-effectiveness ratio (ICER), and effectiveness was measured in quality-adjusted life years (QALYs). To account for uncertainty, 1-way, 2-way and probabilistic sensitivity analyses were performed. Strategies were evaluated with a willingness-to-pay (WTP) threshold of $100,000 per QALY gained. Results: Base case pain relief after the treatment was assumed as 20% higher in SBRT. Base case treatment costs for SBRT and EBRT were $9000 and $1087, respectively. In the base case analysis, SBRT resulted in an ICER of $124,552 per QALY gained. In 1-way sensitivity analyses, results were most sensitive to variation of the utility of unrelieved pain; the utility of relieved pain after initial treatment and median survival were also sensitive to variation. If median survival is ≥11 months, SBRT cost <$100,000 per QALY gained. Conclusion: SBRT for palliation of vertebral bone metastases is not cost-effective compared with EBRT at a $100,000 per QALY gained WTP threshold. However, if median survival is ≥11 months, SBRT costs ≤$100

  2. Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer

    PubMed Central

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

    2015-01-01

    Background Stereotactic body radiotherapy (SBRT) has emerged as an effective treatment for localized prostate cancer. The purpose of this study was to compare the prostate-specific antigen (PSA) kinetics between conventionally fractionated external beam radiotherapy (CF-EBRT) and SBRT boost after whole pelvis EBRT (WP-EBRT) in localized prostate cancer. Methods A total of 77 patients with localized prostate cancer [T-stage, T1–T3; Gleason score (GS) 5–9; PSA < 20 ng/mL] were enrolled. A total of 35 patients were treated with SBRT boost (21 Gy in 3 fractions) after WP-EBRT and 42 patients were treated with CF-EBRT (45 Gy WP-EBRT and boost of 25.2–30.6 Gy in 1.8-Gy fractions). PSA nadir and rate of change in PSA (slope) were calculated and compared. Results With a median follow-up of 52.4 months (range, 14–74 months), the median PSA nadir and slope for SBRT boost were 0.29 ng/mL and −0.506, −0.235, −0.129, and −0.092 ng/mL/mo, respectively, for durations of 1 year, 2 years, 3 years, and 4 years postradiotherapy. Similarly, for CF-EBRT, the median PSA nadir and slopes were 0.39 ng/mL and −0.720 ng/mL/mo, −0.204 ng/mL/mo, −0.121 ng/mL/mo, and −0.067 ng/mL/mo, respectively. The slope of CF-EBRT was significantly different with a greater median rate of change for 1 year postradiotherapy than that of SBRT boost (P = 0.018). Contrastively, the slopes of SBRT boost for durations of 2 years, 3 years, and 4 years tended to be continuously greater than that of CF-EBRT. The significantly lower PSA nadir was observed in SBRT boost (median nadir 0.29 ng/mL) compared with CF-EBRT (median nadir 0.35 ng/mL, P = 0.025). Five-year biochemical failure (BCF) free survival was 94.3% for SBRT boost and 78.6% for CF-EBRT (P = 0.012). Conclusion Patients treated with SBRT boost after WP-EBRT experienced a lower PSA nadir and there tended to be a continuously greater rate of decline of PSA for durations of 2 years, 3 years, and

  3. Increasing trend of primary NO(2) exhaust emission fraction in Hong Kong.

    PubMed

    Tian, Linwei; Hossain, Sarah R; Lin, Hualiang; Ho, Kin Fai; Lee, Shun Cheng; Yu, Ignatius T S

    2011-12-01

    Despite the successful reduction in roadside NO( x ) levels, no such decrease has been detected in roadside NO(2) concentration in Hong Kong. One underlying cause could be the rising primary NO(2) fraction of the total emission of NO( x ). Primary NO(2) can be particularly detrimental to Hong Kong because a large fraction of the population are exposed to the traffic-related primary pollutants in the street canyons formed by congested high-rise buildings. In this study, hourly mean concentration data for roadside nitrogen oxides (NO( x )), nitrogen dioxide (NO(2)), and background ozone (O(3)) were used to estimate the mean primary NO(2) fraction from vehicle exhausts in Hong Kong. An overall increasing trend was observed for the primary NO(2) fraction (f-NO(2)) values in all the three roadside air monitoring sites. The primary NO(2) as a fraction of total NO( x ) (f-NO(2)) increased approximately from 2% in 1998 to 13% in 2008 in Hong Kong. The two particular periods of rising f-NO(2) coincided with the two implementation periods of the diesel retrofit programs for the light-duty vehicles and heavy-duty vehicles. Future vehicle emission control strategies should target not only total NO( x ) but also primary NO(2). Health benefit or disease burden estimates should be taken into account and updated in the process of policy planning and evaluation. PMID:21331790

  4. Analyzing Pre-Service Primary Teachers' Fraction Knowledge Structures through Problem Posing

    ERIC Educational Resources Information Center

    Kilic, Cigdem

    2015-01-01

    In this study it was aimed to determine pre-service primary teachers' knowledge structures of fraction through problem posing activities. A total of 90 pre-service primary teachers participated in this study. A problem posing test consisting of two questions was used and the participants were asked to generate as many as problems based on the…

  5. 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

  6. Stereotactic body radiotherapy using CyberKnife for locally advanced unresectable and metastatic pancreatic cancer

    PubMed Central

    Su, Ting-Shi; Liang, Ping; Lu, Huan-Zhen; Liang, Jian-Ning; Liu, Jian-Min; Zhou, Ying; Gao, Ying-Chuan; Tang, Min-Yang

    2015-01-01

    AIM: To evaluate the efficacy and toxicity of stereotactic body radiotherapy using CyberKnife for locally advanced unresectable and metastatic pancreatic cancer. METHODS: From June 2010 to May 2014, 25 patients with locally advanced unresectable and metastatic pancreatic cancer underwent stereotactic body radiotherapy. Nine patients presented with unresectable locally advanced disease and 16 had metastatic disease. Primary end-points of this study were overall survival, relief of abdominal pain, and toxicity. RESULTS: Fourteen patients were treated with a total dose of 30-36 Gy in three fractions and the remainder with 40-48 Gy in four fractions. Median follow-up was 11 mo (range: 2-25 mo). The median survival duration calculated from the time of stereotactic body radiotherapy for the entire group, the locally advanced group, and the metastatic group was 9.0 mo, 13.5 mo, and 8.5 mo, respectively. Overall survival was 37% and 18% at one and two years, respectively. Abdominal pain relief was achieved within 2 wk of completing radiotherapy in the patients who received successful palliation (13 of 20 patients had significant pain). Five patients (20%) had grade 1 nausea, and one (4%) had grade 2 nausea. No acute grade 3+ toxicity was seen. CONCLUSION: Stereotactic body radiotherapy using the CyberKnife system is a promising, noninvasive, palliative treatment with acceptable toxicity for locally advanced unresectable and metastatic pancreatic cancer. PMID:26185389

  7. Efficacy of stereotactic gamma knife surgery and microvascular decompression in the treatment of primary trigeminal neuralgia: a retrospective study of 220 cases from a single center

    PubMed Central

    Dai, Zi-Feng; Huang, Qi-Lin; Liu, Hai-Peng; Zhang, Wei

    2016-01-01

    Objectives A retrospective study was undertaken to compare the efficacy of stereotactic gamma knife surgery (GKS) and microvascular decompression (MVD) in the treatment of primary trigeminal neuralgia (TN) at a single center. The study included the evaluation of clinical outcomes of pain relief and pain recurrence and complications associated with GKS and MVD. Methods The study included 202 patients with primary TN and was conducted between January 2013 and December 2014; about 115 patients were treated with GKS and 87 patients were treated with MVD. TN pain was evaluated using the Barrow Neurological Institute and the visual analog scale scoring systems. Preoperative magnetic resonance tomographic angiography was performed for all patients. Microscope-assisted MVD used the suboccipital retrosigmoid sinus approach. GKS targeted the trigeminal nerve root entry zone with a margin radiation dose of 59.5 Gy, and brainstem dose <12 Gy. Posttreatment follow-up was for 2 years. Results Postoperative Barrow Neurological Institute scores for patients treated with GKS and MVD were significantly improved compared with preoperative scores (P<0.01). Reduction in postoperative pain following MVD (95.4% patients) was significantly greater than that following GKS (88.7% patients) (P<0.01). Postoperative visual analog scale scores of the MVD group were significantly reduced compared with those of patients treated with GKS at the same postoperative time points (P<0.01). Patients treated with GKS had a significantly increased rate of loss of corneal reflex compared with patients treated with MVD (P=0.002). Conclusion Both GKS and MVD are safe and effective first-line and adjunctive treatment options for patients with TN. The clinical outcomes of pain relief and reduction of pain recurrence were better with MVD. For GKS, this study showed that the optimal radiation therapeutic dose range was 70–90 Gy, but brainstem radiation protection is recommended. PMID:27555796

  8. Clinical Assessment Of Stereotactic IGRT: Spinal Radiosurgery

    SciTech Connect

    Gerszten, Peter C. Burton, Steven A.

    2008-07-01

    The role of stereotactic radiosurgery for the treatment of intracranial lesions is well established. Its use for the treatment of spinal lesions has been limited because of the availability of effective target immobilization devices. Recent advances in stereotactic IGRT have allowed for spinal applications. Large clinical experience with spinal radiosurgery to properly assess clinical outcomes has previously been limited. At our institution, we have developed a successful multidisciplinary spinal radiosurgery program in which 542 spinal lesions (486 malignant and 56 benign lesions) were treated with a single-fraction radiosurgery technique. Patient ages ranged from 18 to 85 years (mean 56 years). Lesion location included 92 cervical, 234 thoracic, 130 lumbar, and 86 sacral. The most common metastatic tumors were renal cell (89 cases), breast (74 cases), and lung (71 cases). The most common benign tumors were neurofibroma (24 cases), schwannoma (13 cases), and meningioma (7 cases). Eighty-nine cervical lesions were treated using skull tracking. Thoracic, lumbar, and sacral tumors were tracked relative to either gold or stainless steel fiducial markers. The maximum intratumoral dose ranged from 12.5 to 30 Gy (mean 20 Gy). Tumor volume ranged from 0.16 to 298 mL (mean 47 mL). Three hundred thirty-seven lesions had received prior external beam irradiation with spinal cord doses precluding further conventional irradiation. The primary indication for radiosurgery was pain in 326 cases, as a primary treatment modality in 70 cases, for tumor radiographic tumor progression in 65 cases, for post-surgical treatment in 38 cases, for progressive neurological deficit in 35 cases, and as a radiation boost in 8 cases. Follow-up period was at least 3 to 49 months. Axial and/or radicular pain improved in 300 of 326 cases (92%). Long-term tumor control was demonstrated in 90% of lesions treated with radiosurgery as a primary treatment modality and in 88% of lesions treated for

  9. Differences in rates of radiation-induced true and false rib fractures after stereotactic body radiation therapy for Stage I primary lung cancer

    PubMed Central

    Miura, Hideharu; Inoue, Toshihiko; Shiomi, Hiroya; Oh, Ryoong-Jin

    2015-01-01

    The purpose of this study was to analyze the dosimetry and investigate the clinical outcomes of radiation-induced rib fractures (RIRFs) after stereotactic body radiotherapy (SBRT). A total of 126 patients with Stage I primary lung cancer treated with SBRT, who had undergone follow-up computed tomography (CT) at least 12 months after SBRT and who had no previous overlapping radiation exposure were included in the study. We used the Mantel–Haenszel method and multiple logistic regression analysis to compare risk factors. We analyzed D(0.5 cm3) (minimum absolute dose received by a 0.5-cm3 volume) and identified each rib that received a biologically effective dose (BED) (BED3, using the linear–quadratic (LQ) formulation assuming an α/β = 3) of at least 50 Gy. Of the 126 patients, 46 (37%) suffered a total of 77 RIRFs. The median interval from SBRT to RIRF detection was 15 months (range, 3–56 months). The 3-year cumulative probabilities were 45% (95% CI, 34–56%) and 3% (95% CI, 0–6%), for Grades 1 and 2 RIRFs, respectively. Multivariate analysis showed that tumor location was a statistically significant risk factor for the development of Grade 1 RIRFs. Of the 77 RIRFs, 71 (92%) developed in the true ribs (ribs 1–7), and the remaining six developed in the false ribs (ribs 8–12). The BED3 associated with 10% and 50% probabilities of RIRF were 55 and 210 Gy to the true ribs and 240 and 260 Gy to the false ribs. We conclude that RIRFs develop more frequently in true ribs than in false ribs. PMID:25504640

  10. Proton Beam Radiotherapy Versus Three-Dimensional Conformal Stereotactic Body Radiotherapy in Primary Peripheral, Early-Stage Non-Small-Cell Lung Carcinoma: A Comparative Dosimetric Analysis

    SciTech Connect

    Macdonald, O. Kenneth; Kruse, Jon J.; Miller, Janelle M.; Garces, Yolanda I.; Brown, Paul D.; Miller, Robert C.; Foote, Robert L.

    2009-11-01

    Purpose: Proton radiotherapy (PT) and stereotactic body radiotherapy (SBRT) have the capacity to optimize the therapeutic ratio. We analyzed the dosimetric differences between PT and SBRT in treating primary peripheral early-stage non-small-cell lung cancer. Methods and Materials: Eight patients were simulated, planned, and treated with SBRT according to accepted techniques. SBRT treatments were retrospectively planned using heterogeneity corrections. PT treatment plans were generated using single-, two-, and three-field passively scattered and actively scanned proton beams. Calculated dose characteristics were compared. Results: Comparable planning target volume (PTV) median minimum and maximum doses were observed between PT and SBRT plans. Higher median maximum doses 2 cm from the PTV were observed for PT, but higher median PTV doses were observed for SBRT. The total lung mean and V5 doses were significantly lower with actively scanned PT. The lung V13 and V20 were comparable. The dose to normal tissues was lower with PT except to skin and ribs. Although the maximum doses to skin and ribs were similar or higher with PT, the median doses to these structures were higher with SBRT. Passively scattered plans, compared with actively scanned plans, typically demonstrated higher doses to the PTV, lung, and organs at risk. Conclusions: Single-, two-, or three-field passively or actively scanned proton therapy delivered comparable PTV dose with generally less dose to normal tissues in these hypothetic treatments. Actively scanned beam plans typically had more favorable dose characteristics to the target, lung, and other soft tissues compared with the passively scanned plans. The clinical significance of these findings remains to be determined.

  11. High Dose-Per-Fraction Irradiation of Limited Lung Volumes Using an Image-Guided, Highly Focused Irradiator: Simulating Stereotactic Body Radiotherapy Regimens in a Small-Animal Model

    SciTech Connect

    Cho, Jaeho; Kodym, Reinhard; Seliounine, Serguei

    2010-07-01

    Purpose: To investigate the underlying biology associated with stereotactic body radiotherapy (SBRT), both in vivo models and image-guided, highly focal irradiation systems are necessary. Here, we describe such an irradiation system and use it to examine normal tissue toxicity in a small-animal model at lung volumes similar to those associated with human therapy. Methods and Materials: High-dose radiation was delivered to a small volume of the left lung of C3H/HeJCr mice using a small-animal stereotactic irradiator. The irradiator has a collimation mechanism to produce focal radiation beams, an imaging subsystem consisting of a fluorescent screen coupled to a charge-coupled device camera, and a manual positioning stage. Histopathologic examination and micro-CT were used to evaluate the radiation response. Results: Focal obliteration of the alveoli by fibrous connective tissue, hyperplasia of the bronchiolar epithelium, and presence of a small number of inflammatory cells are the main reactions to low-volume/high-dose irradiation of the mouse lung. The tissue response suggested a radiation dose threshold for early phase fibrosis lying between 40 and 100 Gy. The irradiation system satisfied our requirements of high-dose-rate, small beam diameter, and precise localization and verification. Conclusions: We have established an experimental model and image-guided animal irradiation system for the study of high dose per fraction irradiations such as those used with SBRT at volumes analogous to those used in human beings. It will also allow the targeting of specific anatomical structures of the thorax or ultimately, orthotopic tumors of the lung.

  12. Estimation of primary and secondary particulate matter intake fractions for power plants in Georgia.

    PubMed

    Levy, Jonathan I; Wilson, Andrew M; Evans, John S; Spengler, John D

    2003-12-15

    Air pollution benefit-cost analyses depend on dispersion models to predict population exposures to pollutants, but it is difficult to determine the reasonableness of the model estimates. This is in part because validation with field measurements is not feasible for marginal concentration changes and because few models can capture the necessary spatial and temporal domains with adequate sophistication. In this study, we use the concept of an intake fraction (the fraction of a pollutant or its precursor emitted that is eventually inhaled) to provide insight about population exposures and model performance. We apply CALPUFF, a regional-scale dispersion model common in health benefits assessments, to seven power plants in northern Georgia, considering both direct emissions of fine particulate matter (PM2.5) and secondarily formed ammonium sulfate and ammonium nitrate particles over a domain within 500 km of Atlanta. We estimate emission-weighted average intake fractions of 6 x 10(-7) for primary PM2.5, 2 x 10(-7) for ammonium sulfate from SO2, and 6 x 10(-8) for ammonium nitrate from NOx, with no effect of SO2 on ammonium nitrate. To provide insight about model strengths and limitations, we compare our findings with those from a frequently applied source-receptor (S-R) matrix. Using S-R matrix over an identical domain, the corresponding intake fractions are 5 x 10(-7), 2 x 10(-7), 3 x 10(-8), and -2 x 10(-8), respectively, with the values approximately doubling if the domain is expanded to cover the continental United States. Evaluation of model assumptions and comparison of past intake fraction estimates using these two models illustrates the importance of assumptions about the relative concentrations of ammonia, sulfate, and nitrate, which significantly influences ammonium nitrate intake fractions. These findings provide a framework for improved understanding of the factors that influence population exposures to particulate matter. PMID:14717160

  13. A 3-month age difference profoundly alters the primary rat stromal vascular fraction phenotype.

    PubMed

    Quaade, Marlene Louise; Jensen, Charlotte Harken; Andersen, Ditte Caroline; Sheikh, Søren Paludan

    2016-06-01

    The stromal vascular fraction (SVF) is a heterogeneous population obtained from collagenase digestion of adipose tissue. When cultured the population becomes more homogeneous and the cells are then termed adipose stromal/stem cells (ASCs). Both the freshly isolated primary SVF population and the cultured ASC population possess regenerative abilities suggested to be mediated by paracrine mechanisms mainly. The use of ASCs and SVF cells, both in animal studies and human clinical studies, has dramatically increased during recent years. However, more knowledge regarding optimal donor characteristics such as age is demanded. Here we report that even a short age difference has an impact on the phenotype of primary SVF cells. We observed that a 3-month difference in relatively young adult rats affects the expression pattern of several mesenchymal stem cell markers in their primary SVF. The younger animals had significantly more CD90+/CD44+/CD29+/PDGFRα+primary cells, than the aged rats, suggesting an age dependent shift in the relative cell type distribution within the population. Taken together with recent studies of much more pronounced age differences, our data strongly suggest that donor age is a very critical parameter that should be taken into account in future stem cell studies, especially when using primary cells. PMID:27265810

  14. Stereotactic radiosurgery of brain metastases.

    PubMed

    Specht, Hanno M; Combs, Stephanie E

    2016-09-01

    Brain metastases are a common problem in solid malignancies and still represent a major cause of morbidity and mortality. With the ongoing improvement in systemic therapies, the expectations on the efficacy of brain metastases directed treatment options are growing. As local therapies against brain metastases continue to evolve, treatment patterns have shifted from a palliative "one-treatment-fits-all" towards an individualized, patient adapted approach. In this article we review the evidence for stereotactic radiation treatment based on the current literature. Stereotactic radiosurgery (SRS) as a local high precision approach for the primary treatment of asymptomatic brain metastases has gained wide acceptance. It leads to lasting tumor control with only minor side effects compared to whole brain radiotherapy, since there is only little dose delivered to the healthy brain. The same holds true for hypofractionated stereotactic radiotherapy (HFSRT) for large metastases or for lesions close to organs at risk (e.g. the brainstem). New treatment indications such as neoadjuvant SRS followed by surgical resection or postoperative local therapy to the resection cavity show promising data and are also highlighted in this manuscript. With the evolution of local treatment options, optimal patient selection becomes more and more crucial. This article aims to aid decision making by outlining prognostic factors, treatment techniques and indications and common dose prescriptions. PMID:27071010

  15. 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.

  16. [Stereotactic body radiation radiotherapy for oligometastatic non-small cell lung cancer (NSCLC): A case report].

    PubMed

    Leduc, C; Antoni, D; Quoix, É; Noël, G

    2015-05-01

    Metastatic non-small cell lung cancer is associated with a poor prognosis, and palliative chemotherapy is the mainstay of treatment. However, long-time survival has been observed in oligometastatic patients treated with locally ablative therapies to all sites of metastatic disease. An 80-year-old man was diagnosed with an adenocarcinoma of the lung. The right upper lobe lesion was classified cT2aN0M0 and was treated with stereotactic body radiation therapy at the dose of 60Gy in eight fractions. A few months after, he successively presented with two brain metastases and one left adrenal metastasis, with a complete response on the primary tumor. The three secondary lesions were treated with stereotactic body radiation therapy alone. Thirty months after the diagnosis and 12months after metastases' apparition, primary and brain lesion kept controlled (complete response). Oligometastatic non-small cell lung cancer management is not clear. Locally ablative therapies such as stereotactic body radiation therapy, surgery and radiofrequency are efficient and should be considered. A phase III study should evaluate radical treatment strategies in such patients. PMID:25841992

  17. Breast biopsy - stereotactic

    MedlinePlus

    ... several types of breast biopsies, including open, ultrasound-guided , and lumpectomy . This article focuses on stereotactic breast ... a special machine, a needle or sheath is guided to the exact location of the abnormal area. ...

  18. Accuracy of relocation, evaluation of geometric uncertainties and clinical target volume (CTV) to planning target volume (PTV) margin in fractionated stereotactic radiotherapy for intracranial tumors using relocatable Gill-Thomas-Cosman (GTC) frame.

    PubMed

    Das, Saikat; Isiah, Rajesh; Rajesh, B; Ravindran, B Paul; Singh, Rabi Raja; Backianathan, Selvamani; Subhashini, J

    2011-01-01

    The present study is aimed at determination of accuracy of relocation of Gill-Thomas-Cosman frame during fractionated stereotactic radiotherapy. The study aims to quantitatively determine the magnitudes of error in anteroposterior, mediolateral and craniocaudal directions, and determine the margin between clinical target volume to planning target volume based on systematic and random errors. Daily relocation error was measured using depth helmet and measuring probe. Based on the measurements, translational displacements in anteroposterior (z), mediolateral (x), and craniocaudal (y) directions were calculated. Based on the displacements in x, y and z directions, systematic and random error were calculated and three-dimensional radial displacement vector was determined. Systematic and random errors were used to derive CTV to PTV margin. The errors were within ± 2 mm in 99.2% cases in anteroposterior direction (AP), in 99.6% cases in mediolateral direction (ML), and in 97.6% cases in craniocaudal direction (CC). In AP, ML and CC directions, systematic errors were 0.56, 0.38, 0.42 mm and random errors were 1.86, 1.36 and 0.73 mm, respectively. Mean radial displacement was 1.03 mm ± 0.34. CTV to PTV margins calculated by ICRU formula were 1.86, 1.45 and 0.93 mm; by Stroom's formula they were 2.42, 1.74 and 1.35 mm; by van Herk's formula they were 2.7, 1.93 and 1.56 mm (AP, ML and CC directions). Depth helmet with measuring probe provides a clinically viable way for assessing the relocation accuracy of GTC frame. The errors were within ± 2 mm in all directions. Systematic and random errors were more along the anteroposterior axes. According to the ICRU formula, a margin of 2 mm around the tumor seems to be adequate. PMID:21587166

  19. Size-fractionated dissolved primary production and carbohydrate composition of the coccolithophore Emiliania huxleyi

    NASA Astrophysics Data System (ADS)

    Borchard, C.; Engel, A.

    2014-11-01

    Extracellular release (ER) by phytoplankton is the major source of fresh dissolved organic carbon (DOC) in marine ecosystems and accompanies primary production during all growth phases. Little is known, so far, on size and composition of released molecules, and to which extent ER occurs passively, by leakage, or actively, by exudation. Here, we report on ER by the widespread and bloom-forming coccolithophore Emiliania huxleyi grown under steady state conditions in phosphorus controlled chemostats (N : P = 29, growth rate of μ = 0.2 d-1). 14C incubations were accomplished to determine primary production (PP), comprised by particulate (PO14C) and dissolved organic carbon (DO14C), and the concentration and composition of particulate combined carbohydrates (pCCHO), and of high molecular weight (>1 kDa, HMW) dissolved combined carbohydrates (dCCHO) as major components of ER. Information on size distribution of ER products was obtained by investigating distinct size classes (<0.40 μm, <1000 kDa, <100 kDa and <10 kDa) of DO14C and HMW-dCCHO. Our results revealed relatively low ER during steady state growth, corresponding to ∼4.5% of primary production, and similar ER rates for all size classes. Acidic sugars had a significant share on freshly produced pCCHO as well as on HMW-dCCHO. While pCCHO and the smallest size (<10 kDa) fraction of HMW-dCCHO exhibited a similar sugar composition, dominated by high percentages of glucose (74-80 Mol%), the composition of HMW-dCCHO size-classes >10 kDa was significantly different with higher Mol% of arabinose. Mol% of acidic sugars increased and Mol% glucose decreased with increasing size of HMW-dCCHO. We conclude that larger polysaccharides follow different production and release pathways than smaller molecules, potentially serving distinct ecological and biogeochemical functions.

  20. Biological indicators of exposure to total and respirable aluminium dust fractions in a primary aluminium smelter.

    PubMed Central

    Röllin, H B; Theodorou, P; Cantrell, A C

    1996-01-01

    OBJECTIVES: The study attempts to define biological indicators of aluminium uptake and excretion in workers exposed to airborne aluminium compounds in a primary aluminium smelter. Also, this study defines the total and respirable aluminium dust fractions in two different potrooms, and correlates their concentrations with biological indicators in this group of workers. METHODS: Air was sampled at defined work sites. Non-destructive and conventional techniques were used to find total and respirable aluminium content of the dust. Blood and urine was collected from 84 volunteers employed at various work stations throughout the smelter and from two different cohorts of controls matched for sex, age, and socioeconomic status. Aluminium in serum samples and urine specimens was measured by flameless atomic absorption with a PE 4100 ZL spectrometer. RESULTS: The correlation of aluminium concentrations in serum and urine samples with the degree of exposure was assessed for three arbitrary exposure categories; low (0.036 mg Al/m3), medium (0.35 mg Al/m3) and high (1.47 mg Al/m3) as found in different areas of the smelter. At medium and high exposure, the ratio of respirable to total aluminium in the dust samples varied significantly. At high exposure, serum aluminium, although significantly raised, was still within the normal range of an unexposed population. The workers with low exposure excreted aluminium in urine at levels significantly higher than the controls, but still within the normal range of the population. However, potroom workers with medium and high exposure had significantly higher urinary aluminium than the normal range. CONCLUSIONS: It is concluded that only urinary aluminium constitutes a practical index of occupational exposure at or above 0.35 mg Al/m3, and that the respirable fraction of the dust may play a major role in the biological response to exposure to aluminium in a smelter environment. PMID:8758038

  1. Stereotactic (Mammographically Guided) Breast Biopsy

    MedlinePlus

    ... Z Stereotactic Breast Biopsy Stereotactic breast biopsy uses mammography – a specific type of breast imaging that uses ... the breast are often detected by physical examination, mammography, or other imaging studies. However, it is not ...

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

    PubMed

    Linskey, Mark E

    2013-12-01

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

  3. Sorption and desorption of atrazine and diuron onto water dispersible soil primary size fractions.

    PubMed

    Wang, Peng; Keller, Arturo A

    2009-03-01

    In this study, a low energy separation method was employed to separate water dispersible clay-, silt-, and sand-sized fractions. The batch equilibrium method was used to conduct atrazine and diuron sorption/desorption experiments with the bulk soils and their size fractions separately. A Freundlich sorption model provided the best fit for all sorption and desorption data. A mass balance calculation, taking into account the pesticide concentration differences in the size fraction and bulk soil, showed that pesticide sorption onto the different size fractions reproduces well the total amount of the pesticide sorbed onto the bulk soils. Due to their higher soil organic carbon content, the clay fractions were much more effective sorbents for the pesticides than the bulk soils, silt, and sand fractions. For all soils, the amount of the pesticide sorbed onto the clay fractions was more than 20% of the total amount of the pesticide sorbed by the bulk soils even though the clay fractions in these soils were only 5.3-14.0% (by weight). The clay fractions had the highest desorption hysteresis among all size fractions and the bulk soils, followed by silt fractions, implying the clay fractions had the strongest bound and least desorbable pesticide molecules. Our results suggest that attention should be paid to the pesticide sorbed to the smallest colloids, the water dispersible fraction, which can be potentially mobilized under field conditions, leading to wide spreading of contamination. PMID:19147172

  4. Olefin unit primary fractionator on-line Petro-Blast Lancing

    SciTech Connect

    Adams, W.D.; Rutan, C.R.

    1994-12-31

    Today`s commodity chemicals market forces companies to find innovative ways to extend unit on line operation between turnarounds such that they will remain economically competitive. At the OxyChem Chocolate Bayou facility the Primary Fractionator, quench oil column, fouling defined the length of the run between Olefin Unit turnarounds. Polymer growth on the valve trays restricted vapor flow through the column. This increased the column pressure drop which resulted in severe flooding. The inability to cool the furnace effluent while separating the fuel oil and gasoline components would cause premature shutdowns. Fouling locations were defined using gamma scan techniques and pressure surveys. Nozzles were welded and hot tapped at strategic locations around the column. A high pressure Petro-Blast Lancing technique, inserted through the nozzles, was then used to clean the trays. The operation has extended the unit run length although the column may require additional Petro-Blast Lancing before the next scheduled plant turnaround. If this schedule holds, a two year extension in the unit run length will be realized.

  5. Size-fractionated dissolved primary production and carbohydrate composition of the coccolithophore Emiliania huxleyi

    NASA Astrophysics Data System (ADS)

    Borchard, C.; Engel, A.

    2015-02-01

    Extracellular release (ER) by phytoplankton is the major source of fresh dissolved organic carbon (DOC) in marine ecosystems and accompanies primary production during all growth phases. Little is known, so far, on size and composition of released molecules, and to which extent ER occurs passively, by leakage, or actively, by exudation. Here, we report on ER by the widespread and bloom-forming coccolithophore Emiliania huxleyi grown under steady-state conditions in phosphorus-controlled chemostats (N:P = 29, growth rate of μ = 0.2 d-1) at present-day and high-CO2 concentrations. 14C incubations were performed to determine primary production (PP), comprised of particulate (PO14C) and dissolved organic carbon (DO14C). Concentration and composition of particulate combined carbohydrates (pCCHO) and high-molecular-weight (>1 kDa, HMW) dissolved combined carbohydrates (dCCHO) were determined by ion chromatography. Information on size distribution of ER products was obtained by investigating distinct size classes (<0.4 μm (DO14C), <0.45 μm (HMW-dCCHO), <1000, <100 and <10 kDa) of DO14CC and HMW-dCCHO. Our results revealed relatively low ER during steady-state growth, corresponding to ~4.5% of primary production, and similar ER rates for all size classes. Acidic sugars had a significant share on freshly produced pCCHO as well as on HMW-dCCHO. While pCCHO and the smallest size fraction (<10 kDa) of HMW-dCCHO exhibited a similar sugar composition, dominated by high percentage of glucose (74-80 mol%), the composition of HMW-dCCHO size classes >10 kDa was significantly different, with a higher mol% of arabinose. The mol% of acidic sugars increased and that of glucose decreased with increasing size of HMW-dCCHO. We conclude that larger polysaccharides follow different production and release pathways than smaller molecules, potentially serving distinct ecological and biogeochemical functions.

  6. Automated stereotactic positioning system.

    PubMed

    Goerss, S J; Kelly, P J; Kall, B A

    1987-01-01

    An automated stereotactic machine has been interfaced to a surgical computer to complete a totally interactive surgical system capable of locating tumor volumes. Stepper motors, activated by the host computer, drive a three-dimensional slide to position the patient's head with respect to a fixed arc, locating the surgical target. Linear encoders on each axis create a closed-loop positioning system and a digital display for visual inspection of the slide's position. The 160-mm arc directs all instrumentation to its isocenter, regardless of the two angular settings, providing maximum freedom in selecting a safe trajectory to the target. Phantom test points compatible with computerized tomographic and magnetic resonance imaging were repeatedly scanned to determine the overall system accuracy, which approached 0.6 mm, depending on the spatial resolution of the image. This stereotactic device may be used to perform stereotactic laser craniotomies, biopsies, 192Ir implants for interstitial radiation, third ventriculostomies and functional procedures. PMID:3329830

  7. Correction for volatile fractionation in ascending magmas: noble gas abundances in primary mantle melts

    NASA Astrophysics Data System (ADS)

    Burnard, Pete

    2001-09-01

    Accurate relative noble gas abundances of mantle-derived melts are required in order to further understand the distribution of noble gases in the mantle and fractionation of noble gases during the melting process. Noble gas relative abundances in the majority of oceanic basalts are highly fractionated, at least in part due to late stage, solubility controlled fractionation. Noble gas concentrations in the volatile phase (≡ noble gas:CO 2 ratio) will vary systematically during solubility controlled degassing of a magma. This contribution models the noble gas concentrations in the volatile phase during degassing at different pressures and vesicularities in order to develop a method for correcting fractionation resulting from magmatic degassing, and thereby estimate the "initial" (pre-degassing) noble gas compositions. Correcting for fractionation during magmatic degassing requires: a) a method for determining the volatile fractionation trajectory during degassing; and b) one well constrained mantle volatile composition with which to "fix" the extrapolation. The trajectory of volatile fractionation can be estimated by sequential crushing of basaltic glasses. Vesicles grow during ascent, therefore large vesicles trap early (less fractionated) volatiles while small vesicles trap late (fractionated) volatiles. Sequential crushing of basaltic glasses releases volatiles from progressively smaller vesicles, thereby allowing the fractionation trajectory resulting from degassing to be determined on individual samples. The production rate of both 21Ne and 4He in the mantle is a function of U concentration only, resulting in a constant 21Ne/ 4He production ratio in the mantle which can be used to "fix" the degassing fractionation trajectory determined by sequential crushing. This correction then allows fractionation of 4He from 40Ar prior to degassing to be assessed. This method is illustrated using multiple crushes of a single basaltic glass from the mid-Atlantic Ridge that

  8. Prognostic factors affecting local control of hepatic tumors treated by stereotactic body radiation therapy

    PubMed Central

    2012-01-01

    Purpose Robotic Stereotactic Body Radiation Therapy with real-time tumor tracking has shown encouraging results for hepatic tumors with good efficacy and low toxicity. We studied the factors associated with local control of primary or secondary hepatic lesions post-SBRT. Methods and materials Since 2007, 153 stereotactic liver treatments were administered to 120 patients using the CyberKnife® System. Ninety-nine liver metastases (72 patients), 48 hepatocellular carcinomas (42 patients), and six cholangiocarcinomas were treated. On average, three to four sessions were delivered over 12 days. Twenty-seven to 45 Gy was prescribed to the 80% isodose line. Margins consisted of 5 to 10 mm for clinical target volume (CTV) and 3 mm for planning target volume (PTV). Results Median size was 33 mm (range, 5–112 mm). Median gross tumor volume (GTV) was 32.38 cm3 (range, 0.2–499.5 cm3). Median total dose was 45 Gy in three fractions. Median minimum dose was 27 Gy in three fractions. With a median follow-up of 15.0 months, local control rates at one and two years were 84% and 74.6%, respectively. The factors associated with better local control were lesion size < 50 mm (p = 0.019), GTV volume (p < 0.05), PTV volume (p < 0.01) and two treatment factors: a total dose of 45 Gy and a dose–per-fraction of 15 Gy (p = 0.019). Conclusions Dose, tumor diameter and volume are prognostic factors for local control when a stereotactic radiation therapy for hepatic lesions is considered. These results should be considered in order to obtain a maximum therapeutic efficacy. PMID:23050794

  9. Frameless Image-Guided Intracranial Stereotactic Radiosurgery: Clinical Outcomes for Brain Metastases

    SciTech Connect

    Breneman, John C. Steinmetz, Ryan; Smith, Aaron; Lamba, Michael; Warnick, Ronald E.

    2009-07-01

    Purpose: After preclinical investigations confirming the accuracy of target localization by frameless image-guided radiosurgery, we report the clinical outcomes of patients with brain metastases who underwent frameless radiosurgery. Methods and Materials: Between 2005 and 2006, 53 patients underwent frameless stereotactic radiosurgery using a linear accelerator equipped with on-board image guidance for the treatment of 158 brain metastases. The radiation doses were delivered in a single fraction (dose range, 12-22 Gy; median, 18). Patients were followed with magnetic resonance imaging scans at 2-3-month intervals. Progression-free survival was the primary study endpoint. Results: With a median follow-up of 38 weeks (range, 14-112), the overall survival rate was 70% at 6 months, 44% at 1 year, 29% at 18 months, and 16% at 24 months. Local control was achieved in 90% of 168 treated lesions at 6 months, 80% at 12 months, 78% at 18 months, and 78% at 24 months. Local control tended to be improved in lesions treated with {>=}18 Gy and for lesions <0.2 cm{sup 3}. Adverse events occurred in 5 patients (9.6%). No evidence of imaging changes on post-stereotactic radiosurgery scans was found to suggest mistargeting of a radiation isocenter. Conclusion: The clinical outcomes after frameless stereotactic radiosurgery were comparable to those after frame-based radiosurgery techniques. Given its significant advantages in terms of patient comfort, ability to use fractionated treatment regimens, and convenience in scheduling of personnel and equipment resources, frameless radiosurgery will likely become a common technique for intracranial radiosurgery.

  10. 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

  11. Stereotactic radiosurgery and stereotactic radiotherapy for brain metastases.

    PubMed

    Halasz, Lia M; Rockhill, Jason K

    2013-01-01

    Stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (HFSRT) have become important treatment modalities for brain metastases. While effective, there are still areas of extensive debate on its appropriate use in patients with life-limiting diseases. This review provides an overview of the indications and challenges of SRS and HFSRT in the management of brain metastases. PMID:23717789

  12. The role of stereotactic ablative radiotherapy in oncological and non-oncological clinical settings: highlights from the 7th Meeting of AIRO--Young Members Working Group (AIRO Giovani).

    PubMed

    Franco, Pierfrancesco; De Bari, Berardino; Ciammella, Patrizia; Fiorentino, Alba; Chiesa, Silvia; Amelio, Dante; Pinzi, Valentina; Bonomo, Pierluigi; Vagge, Stefano; Fiore, Michele; Comito, Tiziana; Cecconi, Agnese; Mortellaro, Gianluca; Bruni, Alessio; Trovò, Marco; Filippi, Andrea Riccardo; Greto, Daniela; Alongi, Filippo

    2014-01-01

    Stereotactic ablative radiotherapy is a modern cancer treatment strategy able to deliver highly focused radiation in one or a few fractions with a radical intent in several clinical settings. Young radiation oncologists need a constant and tailored update in this context to improve patient care in daily clinical practice. A recent meeting of AIRO Giovani (AIRO--Young Members Working Group) was specifically addressed to this topic, presenting state-of-the-art knowledge, based on the latest evidence in this field. Highlights of the congress are summarized and presented in this report, including thorough contributions of the speakers dealing with the role of stereotactic ablative radiotherapy in both oncological and non-oncological diseases, divided according to anatomical and clinical scenarios: intra-cranial settings (brain malignant primary tumors, metastases, benign tumors and functional disorders) and extra-cranial indications (lung primary tumors and metastases, thoracic re-irradiation, liver, lymph node and bone metastases, prostate cancer). With literature data discussed during the congress as a background, stereotactic ablative radiotherapy has proved to be a consolidated treatment approach in specific oncological and non-oncological scenarios, as well as a promising option in other clinical settings, requiring a further prospective validation in the near future. We herein present an updated overview of stereotactic ablative radiotherapy use in the clinic. PMID:25688503

  13. Stereotactic surgery for eating disorders.

    PubMed

    Sun, Bomin; Liu, Wei

    2013-01-01

    EATING DISORDERS (EDS) ARE A GROUP OF SEVERELY IMPAIRED EATING BEHAVIORS, WHICH INCLUDE THREE SUBGROUPS: anorexia nervosa (AN), bulimia nervosa (BN), and ED not otherwise specified (EDNOS). The precise mechanism of EDs is still unclear and the disorders cause remarkable agony for the patients and their families. Although there are many available treatment methods for EDs today, such as family therapy, cognitive behavioral therapy, medication, psychotherapy, and so on, almost half of the patients are refractory to all current medical treatment and never fully recover. For treatment-refractory EDs, stereotactic surgery may be an alternative therapy. This review discusses the history of stereotactic surgery, the modern procedures, and the mostly used targets of stereotactic surgery in EDs. In spite of the limited application of stereotactic surgery in ED nowadays, stereotactic lesion and deep brain stimulation (DBS) are promising treatments with the development of modern functional imaging techniques and the increasing understanding of its mechanism in the future. PMID:23682343

  14. Stereotactic surgery for eating disorders

    PubMed Central

    Sun, Bomin; Liu, Wei

    2013-01-01

    Eating disorders (EDs) are a group of severely impaired eating behaviors, which include three subgroups: anorexia nervosa (AN), bulimia nervosa (BN), and ED not otherwise specified (EDNOS). The precise mechanism of EDs is still unclear and the disorders cause remarkable agony for the patients and their families. Although there are many available treatment methods for EDs today, such as family therapy, cognitive behavioral therapy, medication, psychotherapy, and so on, almost half of the patients are refractory to all current medical treatment and never fully recover. For treatment-refractory EDs, stereotactic surgery may be an alternative therapy. This review discusses the history of stereotactic surgery, the modern procedures, and the mostly used targets of stereotactic surgery in EDs. In spite of the limited application of stereotactic surgery in ED nowadays, stereotactic lesion and deep brain stimulation (DBS) are promising treatments with the development of modern functional imaging techniques and the increasing understanding of its mechanism in the future. PMID:23682343

  15. Multicentre results of stereotactic body radiotherapy for secondary liver tumours

    PubMed Central

    Berber, Betul; Ibarra, Rafael; Snyder, Laura; Yao, Min; Fabien, Jeffrey; Milano, Michael T; Katz, Alan W; Goodman, Karyn; Stephans, Kevin; El-Gazzaz, Galal; Aucejo, Federico; Miller, Charles; Fung, John; Lo, Simon; Machtay, Mitchell; Sanabria, Juan

    2013-01-01

    Background Surgical resection is the standard treatment for liver metastases, although for the majority of patients this is not possible. Stereotactic body radiotherapy (SBRT) is an alternative local-regional therapy. The purpose of this study was to evaluate the results of SBRT for secondary liver tumours from a combined multicentre database. Methods Variables from patients treated with SBRT from four Academic Medical Centres were entered into a common database. Local tumour control and 1-year survival rates were calculated. Results In total, 153 patients (91 women) 59 ± 8.4 years old with 363 metastatic liver lesions were treated with SBRT. The underlying primary tumour arose from gastrointestinal (GI), retroperitoneal and from extra-abdominal primaries in 56%, 8% and 36% of patients, respectively. Metastases, with a gross tumour volume (GTV) of 138.5 ± 126.8 cm3, were treated with a total radiation dose of 37.5 ± 8.2 Gy in 5 ± 3 fractions. The 1-year overall survival was 51% with an overall local control rate of 62% at a mean follow-up of 25.2 ± 5.9 months. A complete tumour response was observed in 32% of patients. Grade 3–5 adverse events were noted in 3% of patients. Conclusion Secondary liver tumours treated with SBRT had a high rate of local control with a low incidence of adverse events. PMID:23458468

  16. Tomotherapy and stereotactic radiosurgery

    NASA Astrophysics Data System (ADS)

    Soisson, Emilie T.

    Currently, at the University of Wisconsin-Madison, a linear accelerator equipped with circular collimators and a floor stand is used for stereotactic radiosurgery (SRS) delivery. In the interest of providing a more efficient delivery option for patients with multiple brain metastases, a Tomotherapy-based radiosurgery program was developed to serve as an intensity modulated compliment to our existing delivery method. The unique advantage of Tomotherapy over other radiotherapy delivery units is the on board megavoltage CT that can be used for both stereotactic localization and treatment planning. As such, a workflow was designed in which the planning image is acquired on the treatment unit itself and, instead using a patient-frame based coordinate system for stereotactic localization, volumetric imaging is used to precisely locate the target at the time of treatment. Localization and delivery accuracy was found to be comparable to conventional approaches and well within stated tolerances. A Tomotherapy-specific treatment planning technique was also developed using the Tomotherapy treatment planning system that reliably produces plans that achieve both conformal target coverage and sufficiently steep dose falloff into surrounding normal brain. Tomotherapy plans have been compared to conventional circular collimator based plans for both the treatment of brain metastases and arteriovenous malformations in terms of both target conformity and dose to normal brain. To determine the effect of plan differences on patient outcome, clinical data was used to predict the resulting risk of treatment induced symptomatic brain necrosis for both conventional and Tomotherapy based plans. Overall, it was determined that plans generated using the described planning technique are acceptable for radiosurgery. In addition, delivery time for complex cases is comparable to or improved over conventional isocentric approaches. Finally, this work explores the impact of future product

  17. Radiobiological mechanisms of stereotactic body radiation therapy and stereotactic radiation surgery

    PubMed Central

    Kim, Mi-Sook; Kim, Wonwoo; Park, In Hwan; Kim, Hee Jong; Lee, Eunjin; Jung, Jae-Hoon; Cho, Lawrence Chinsoo

    2015-01-01

    Despite the increasing use of stereotactic body radiation therapy (SBRT) and stereotactic radiation surgery (SRS) in recent years, the biological base of these high-dose hypo-fractionated radiotherapy modalities has been elusive. Given that most human tumors contain radioresistant hypoxic tumor cells, the radiobiological principles for the conventional multiple-fractionated radiotherapy cannot account for the high efficacy of SBRT and SRS. Recent emerging evidence strongly indicates that SBRT and SRS not only directly kill tumor cells, but also destroy the tumor vascular beds, thereby deteriorating intratumor microenvironment leading to indirect tumor cell death. Furthermore, indications are that the massive release of tumor antigens from the tumor cells directly and indirectly killed by SBRT and SRS stimulate anti-tumor immunity, thereby suppressing recurrence and metastatic tumor growth. The reoxygenation, repair, repopulation, and redistribution, which are important components in the response of tumors to conventional fractionated radiotherapy, play relatively little role in SBRT and SRS. The linear-quadratic model, which accounts for only direct cell death has been suggested to overestimate the cell death by high dose per fraction irradiation. However, the model may in some clinical cases incidentally do not overestimate total cell death because high-dose irradiation causes additional cell death through indirect mechanisms. For the improvement of the efficacy of SBRT and SRS, further investigation is warranted to gain detailed insights into the mechanisms underlying the SBRT and SRS. PMID:26756026

  18. 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.

  19. Stereotactic Body Radiotherapy for Treatment of Adrenal Metastases

    SciTech Connect

    Chawla, Sheema; Chen, Yuhchyau; Katz, Alan W.; Muhs, Ann G.; Philip, Abraham; Okunieff, Paul; Milano, Michael T.

    2009-09-01

    Purpose: To investigate the dosimetry and outcomes of patients undergoing stereotactic body radiotherapy (SBRT) for metastases to the adrenal glands. Methods and Materials: At University of Rochester, patients have been undergoing SBRT for limited metastases since 2001. We retrospectively reviewed 30 patients who had undergone SBRT for adrenal metastases from various primary sites, including lung (n = 20), liver (n = 3), breast (n = 3), melanoma (n = 1), pancreas (n = 1), head and neck (n = 1), and unknown primary (n = 1). Results: Of the 30 patients, 14 with five or fewer metastatic lesions (including adrenal) underwent SBRT, with the intent of controlling all known sites of metastatic disease, and 16 underwent SBRT for palliation or prophylactic palliation of bulky adrenal metastases. The prescribed dose ranged from 16 Gy in 4 fractions to 50 Gy in 10 fractions. The median dose was 40 Gy. Of the 30 patients, 24 had >3 months of follow-up with serial computed tomography. Of these 24 patients, 1 achieved a complete response, 15 achieved a partial response, 4 had stable disease, and 4 developed progressive disease. No patient developed symptomatic progression of their adrenal metastases. The 1-year survival, local control, and distant control rate was 44%, 55%, and 13%, respectively. No patient developed Radiation Therapy Oncology Group Grade 2 or greater toxicity. Conclusion: SBRT for adrenal metastases is well tolerated. Most patients developed widespread metastases shortly after treatment. Local control was poor, although this was a patient population selected for adverse risk factors, such as bulky disease. Additional studies are needed to determine the efficacy of SBRT for oligometastatic adrenal metastases, given the propensity of these patients to develop further disease progression.

  20. Stereotactic Radiotherapy for Adrenal Gland Metastases: University of Florence Experience

    SciTech Connect

    Casamassima, Franco; Livi, Lorenzo; Masciullo, Stefano; Menichelli, Claudia; Masi, Laura; Meattini, Icro; Bonucci, Ivano; Agresti, Benedetta; Simontacchi, Gabriele; Doro, Raffaela

    2012-02-01

    Purpose: To evaluate a retrospective single-institution outcome after hypofractionated stereotactic body radiotherapy (SBRT) for adrenal metastases. Methods and Materials: Between February 2002 and December 2009, we treated 48 patients with SBRT for adrenal metastases. The median age of the patient population was 62.7 years (range, 43-77 years). In the majority of patients, the prescription dose was 36 Gy in 3 fractions (70% isodose, 17.14 Gy per fraction at the isocenter). Eight patients were treated with single-fraction stereotactic radiosurgery and forty patients with multi-fraction stereotactic radiotherapy. Results: Overall, the series of patients was followed up for a median of 16.2 months (range, 3-63 months). At the time of analysis, 20 patients were alive and 28 patients were dead. The 1- and 2-year actuarial overall survival rates were 39.7% and 14.5%, respectively. We recorded 48 distant failures and 2 local failures, with a median interval to local failure of 4.9 months. The actuarial 1-year disease control rate was 9%; the actuarial 1- and 2-year local control rate was 90%. Conclusion: Our retrospective study indicated that SBRT for the treatment of adrenal metastases represents a safe and effective option with a control rate of 90% at 2 years.

  1. Evaluation of the European population intake fractions for European and Finnish anthropogenic primary fine particulate matter emissions

    NASA Astrophysics Data System (ADS)

    Tainio, Marko; Sofiev, Mikhail; Hujo, Mika; Tuomisto, Jouni T.; Loh, Miranda; Jantunen, Matti J.; Karppinen, Ari; Kangas, Leena; Karvosenoja, Niko; Kupiainen, Kaarle; Porvari, Petri; Kukkonen, Jaakko

    The intake fraction (iF) has been defined as the integrated incremental intake of a pollutant released from a source category or region summed over all exposed individuals. In this study we evaluated the iFs in the population of Europe for emissions of anthropogenic primary fine particulate matter (PM 2.5) from sources in Europe, with a more detailed analysis of the iF from Finnish sources. Parameters for calculating the iFs include the emission strengths, the predicted atmospheric concentrations, European population data, and the average breathing rate per person. Emissions for the whole of Europe and Finland were based on the inventories of the European Monitoring and Evaluation Programme (EMEP) and the Finnish Regional Emission Scenario (FRES) model, respectively. The atmospheric dispersion of primary PM 2.5 was computed using the regional-scale dispersion model SILAM. The iFs from Finnish sources were also computed separately for six emission source categories. The iFs corresponding to the primary PM 2.5 emissions from the European countries for the whole population of Europe were generally highest for the densely populated Western European countries, second highest for the Eastern and Southern European countries, and lowest for the Northern European and Baltic countries. For the entire European population, the iF values varied from the lowest value of 0.31 per million for emissions from Cyprus, to the highest value of 4.42 per million for emissions from Belgium. These results depend on the regional distribution of the population and the prevailing long-term meteorological conditions. Regarding Finnish primary PM 2.5 emissions, the iF was highest for traffic emissions (0.68 per million) and lowest for major power plant emissions (0.50 per million). The results provide new information that can be used to find the most cost-efficient emission abatement strategies and policies.

  2. Three-Staged Stereotactic Radiotherapy Without Whole Brain Irradiation for Large Metastatic Brain Tumors

    SciTech Connect

    Higuchi, Yoshinori Serizawa, Toru; Nagano, Osamu; Matsuda, Shinji; Ono, Junichi; Sato, Makoto; Iwadate, Yasuo; Saeki, Naokatsu

    2009-08-01

    Purpose: To evaluate the efficacy and toxicity of staged stereotactic radiotherapy with a 2-week interfraction interval for unresectable brain metastases more than 10 cm{sup 3} in volume. Patients and Methods: Subjects included 43 patients (24 men and 19 women), ranging in age from 41 to 84 years, who had large brain metastases (> 10 cc in volume). Primary tumors were in the colon in 14 patients, lung in 12, breast in 11, and other in 6. The peripheral dose was 10 Gy in three fractions. The interval between fractions was 2 weeks. The mean tumor volume before treatment was 17.6 {+-} 6.3 cm{sup 3} (mean {+-} SD). Mean follow-up interval was 7.8 months. The local tumor control rate, as well as overall, neurological, and qualitative survivals, were calculated using the Kaplan-Meier method. Results: At the time of the second and third fractions, mean tumor volumes were 14.3 {+-} 6.5 (18.8% reduction) and 10.6 {+-} 6.1 cm{sup 3} (39.8% reduction), respectively, showing significant reductions. The median overall survival period was 8.8 months. Neurological and qualitative survivals at 12 months were 81.8% and 76.2%, respectively. Local tumor control rates were 89.8% and 75.9% at 6 and 12 months, respectively. Tumor recurrence-free and symptomatic edema-free rates at 12 months were 80.7% and 84.4%, respectively. Conclusions: The 2-week interval allowed significant reduction of the treatment volume. Our results suggest staged stereotactic radiotherapy using our protocol to be a possible alternative for treating large brain metastases.

  3. Cardiotoxicity of Jamesoni's mamba (Dendroaspis jamesoni) venom and its fractionated components in primary cultures of rat myocardial cells.

    PubMed

    Mbugua, P M; Welder, A A; Acosta, D

    1988-08-01

    Primary cultures of spontaneously beating myocardial cells isolated from neonatal rat hearts were used to screen the cardiotoxic effects of Jamesoni's mamba (Dendroaspis jamesoni) venom and components isolated from the venom by gel filtration and ion exchange chromatography. Cardiotoxicity was evaluated on the basis of leakage of lactate dehydrogenase (LDH), changes in morphology, cell membrane lysis, cellular viability, and alterations in spontaneous beating activity. The whole venom caused dose- and time-dependent leakage of LDH, disruption of the cell monolayer, decreases in viability, and inhibition of beating activity. Gel filtration of the venom yielded eight fractions (DjI to DjVIII). DjI (30 micrograms/ml), DjII (20 micrograms/ml), and DjV (20 micrograms/ml) caused significant (P less than 0.001) leakage of LDH, extensive morphologic damage, and decreases in viability. At lower concentrations DjI to DjVIII caused progressive inhibition of spontaneous beating activity. The main fraction (DjV), which was the most toxic, was further separated into 14 polypeptides (Dj1 to Dj14) by ion-exchange chromatography using Bio-Rex 70. Based on the ability to induce LDH leakage, produce morphologic damage, lyse cell membranes, and arrest beating activity, four categories of polypeptides were identified: cardiotoxins, Dj1 and Dj2; cardiotoxinlike polypeptides, Dj3 to Dj8; less active membrane lytic polypeptides, Dj9 to Dj13; and membrane lytic polypeptide, Dj14. PMID:3410805

  4. A single fraction from Uncaria sinensis exerts neuroprotective effects against glutamate-induced neurotoxicity in primary cultured cortical neurons.

    PubMed

    Kim, Ha Neui; Jang, Ji Yeon; Choi, Byung Tae

    2015-06-01

    We identified a neuroprotective single fraction among 62 ones of hexane extract from Uncaria sinensis (JGH43IA) and investigated its effects and mechanisms in primary cortical neurons. Pretreatment with JGH43IA showed a significantly increase cell viability in a dose-dependent manner with a decrease in the lactate dehydrogenase release. When we performed morphological assay and flow cytometry to determination of the type of cell death, pretreatment with JGH43IA showed a significant reduction of glutamate-induced apoptotic cell death. Then we explored the downstream signaling pathways of N-methyl-D-aspartate receptor (NMDAR) with calpain activation to elucidate possible pathways of neuroprotection by JGH43IA. Pretreatment with JGH43IA exhibited a significant attenuation of NMDAR GluN2B subunit activation and a decrease in active form of calpain 1 leading to subsequent cleavage of striatal-enriched protein tyrosine phosphatase (STEP). In addition, pretreatment with JGH43IA showed a marked increase of cAMP responsive element binding protein. These results suggest that JGH43IA may have neuroprotective effects through down-regulation of NMDAR GluN2B subunit and calpain 1 activation, and subsequent alleviation of STEP cleavage. This single fraction from U. sinensis might be a useful therapeutic agent for brain disorder associated with glutamate injury. PMID:26140220

  5. A single fraction from Uncaria sinensis exerts neuroprotective effects against glutamate-induced neurotoxicity in primary cultured cortical neurons

    PubMed Central

    Kim, Ha Neui; Jang, Ji Yeon

    2015-01-01

    We identified a neuroprotective single fraction among 62 ones of hexane extract from Uncaria sinensis (JGH43IA) and investigated its effects and mechanisms in primary cortical neurons. Pretreatment with JGH43IA showed a significantly increase cell viability in a dose-dependent manner with a decrease in the lactate dehydrogenase release. When we performed morphological assay and flow cytometry to determination of the type of cell death, pretreatment with JGH43IA showed a significant reduction of glutamate-induced apoptotic cell death. Then we explored the downstream signaling pathways of N-methyl-D-aspartate receptor (NMDAR) with calpain activation to elucidate possible pathways of neuroprotection by JGH43IA. Pretreatment with JGH43IA exhibited a significant attenuation of NMDAR GluN2B subunit activation and a decrease in active form of calpain 1 leading to subsequent cleavage of striatal-enriched protein tyrosine phosphatase (STEP). In addition, pretreatment with JGH43IA showed a marked increase of cAMP responsive element binding protein. These results suggest that JGH43IA may have neuroprotective effects through down-regulation of NMDAR GluN2B subunit and calpain 1 activation, and subsequent alleviation of STEP cleavage. This single fraction from U. sinensis might be a useful therapeutic agent for brain disorder associated with glutamate injury. PMID:26140220

  6. Image-Guided Robotic Stereotactic Body Radiation Therapy for Liver Metastases: Is There a Dose Response Relationship?

    SciTech Connect

    Vautravers-Dewas, Claire; Dewas, Sylvain; Bonodeau, Francois; Adenis, Antoine; Lacornerie, Thomas; Penel, Nicolas; Lartigau, Eric; Mirabel, Xavier

    2011-11-01

    Purpose: To evaluate the outcome, tolerance, and toxicity of stereotactic body radiotherapy, using image-guided robotic radiation delivery, for the treatment of patients with unresectable liver metastases. Methods and Material: Patients were treated with real-time respiratory tracking between July 2007 and April 2009. Their records were retrospectively reviewed. Metastases from colorectal carcinoma and other primaries were not necessarily confined to liver. Toxicity was evaluated using National Cancer Institute Common Criteria for Adverse Events version 3.0. Results: Forty-two patients with 62 metastases were treated with two dose levels of 40 Gy in four Dose per Fraction (23) and 45 Gy in three Dose per Fraction (13). Median follow-up was 14.3 months (range, 3-23 months). Actuarial local control for 1 and 2 years was 90% and 86%, respectively. At last follow-up, 41 (66%) complete responses and eight (13%) partial responses were observed. Five lesions were stable. Nine lesions (13%) were locally progressed. Overall survival was 94% at 1 year and 48% at 2 years. The most common toxicity was Grade 1 or 2 nausea. One patient experienced Grade 3 epidermitis. The dose level did not significantly contribute to the outcome, toxicity, or survival. Conclusion: Image-guided robotic stereotactic body radiation therapy is feasible, safe, and effective, with encouraging local control. It provides a strong alternative for patients who cannot undergo surgery.

  7. MO-B-18C-01: Proton Therapy II: Proton Stereotactic Radiotherapy

    SciTech Connect

    Winey, B; Daartz, J

    2014-06-15

    Proton stereotactic radiotherapy shares fundamental principles with general proton therapy physics, specifically range uncertainties and broad beam measurement techniques. Significant differences emerge when treating with smaller field sizes that suffer lateral disequilibrium and when fractions are reduced. This session will explore the history and scope of proton stereotactic radiotherapy in clinical practice. Uncertainties and treatment planning methods specific to stereotactic treatments will be discussed. The session will include an overview of the physical properties of small proton fields and resulting needs for accurate measurements and modeling of dose distributions for radiosurgery treatment planning. Learning Objectives: Understand the clinical rationale for proton radiosurgery. Understand the similarities and differences from general proton therapy. Understand the similarities and differences from photon stereotactic radiosurgery. Understand the basic physics and clinical physics methods for measuring and commissioning a radiosurgery program.

  8. Improving the appropriateness of sudden arrhythmic death primary prevention by implantable cardioverter-defibrillator therapy in patients with low left ventricular ejection fraction. Point of view

    PubMed Central

    Disertori, Marcello; Gulizia, Michele M.; Casolo, Giancarlo; Delise, Pietro; Di Lenarda, Andrea; Di Tano, Giuseppe; Lunati, Maurizio; Mestroni, Luisa; Salerno-Uriarte, Jorge; Tavazzi, Luigi

    2016-01-01

    It is generally accepted that the current guidelines for the primary prevention of sudden arrhythmic death, which are based on ejection fraction, do not allow the optimal selection of patients with low left ventricular ejection fraction of ischemic and nonischemic etiology for implantation of a cardioverter-defibrillator. Ejection fraction alone is limited in both sensitivity and specificity. An analysis of the risk of sudden arrhythmic death with a combination of multiple tests (ejection fraction associated with one or more arrhythmic risk markers) could partially compensate for these limitations. We propose a polyparametric approach for defining the risk of sudden arrhythmic death using ejection fraction in combination with other clinical and arrhythmic risk markers (i.e. late gadolinium enhancement cardiac magnetic resonance, T-wave alternans, programmed ventricular stimulation, autonomic tone, and genetic testing) that have been validated in nonrandomized trials. In this article, we examine these approaches to identify three subsets of patients who cannot be comprehensively assessed by the current guidelines: patients with ejection fraction of 35% or less and a relatively low risk of sudden arrhythmic death despite the ejection fraction value; patients with ejection fraction of 35% or less and high competitive risk of death due to evolution of heart failure or noncardiac causes; and patients with ejection fraction between 35 and 45% with relatively high risk of sudden arrhythmic death despite the ejection fraction value. PMID:26895401

  9. Phase 1 Clinical Trial of Stereotactic Body Radiation Therapy Concomitant With Neoadjuvant Chemotherapy for Breast Cancer

    SciTech Connect

    Bondiau, Pierre-Yves; Courdi, Adel; Bahadoran, Phillipe; Chamorey, Emmanuel; Queille-Roussel, Catherine; Lallement, Michel; Birtwisle-Peyrottes, Isabelle; Chapellier, Claire; Pacquelet-Cheli, Sandrine; Ferrero, Jean-Marc

    2013-04-01

    Purpose: Stereotactic body radiation therapy (SBRT) allows stereotactic irradiation of thoracic tumors. It may have a real impact on patients who may not otherwise qualify for breast-conserving surgery. We conducted a phase 1 trial that tested 5 dose levels of SBRT concomitant with neoadjuvant chemotherapy (NACT) before to surgery. The purpose of the current dose escalation study was to determine the maximum tolerable dose of SBRT in the treatment of breast cancer. Methods and Materials: To define toxicity, we performed dermatologic examinations that included clinical examinations by 2 separate physicians and technical evaluations using colorimetry, dermoscopy, and skin ultrasonography. Dermatologic examinations were performed before NACT, 36 and 56 days after the beginning of NACT, and before surgery. Surgery was performed 4 to 8 weeks after the last chemotherapy session. Efficacy, the primary endpoint, was determined by the pathologic complete response (pCR) rate. Results: Maximum tolerable dose was not reached. Only 1 case of dose-limiting toxicity was reported (grade 3 dermatologic toxicity), and SBRT was overall well tolerated. The pCR rate was 36%, with none being observed at the first 2 dose levels, and the highest rate being obtained at dose level 3 (25.5 Gy delivered in 3 fractions). Furthermore, the breast-conserving surgery rate was up to 92% compared with an 8% total mastectomy rate. No surgical complications were reported. Conclusions: This study demonstrates that SBRT can be safely combined with NACT. Regarding the efficacy endpoints, this trial showed promising results in terms of pCR rate (36%) and breast-conserving rate (92%). The findings provide a strong rationale for extending the study into a phase 2 trial. In view of the absence of correlation between dose and pCR, and given that the data from dose level 3 met the statistical requirements, a dose of 25.5 Gy in 3 fractions should be used for the phase 2 trial.

  10. Stereotactic Body Radiation Therapy for Recurrent Head and Neck Cancer.

    PubMed

    Ling, Diane C; Vargo, John A; Heron, Dwight E

    2016-01-01

    Stereotactic body radiation therapy (SBRT) offers a promising opportunity for cure and/or palliation to patients with recurrent head and neck cancer whose comorbidities, performance status, and history of prior treatment may preclude many other salvage options. Stereotactic body radiation therapy appears to have a favorable response and toxicity profile compared with other nonoperative salvage options for recurrent head and neck cancer. However, the risk of severe toxicity remains, with carotid blowout syndrome a unique concern, although the incidence of this complication may be minimized with alternating-day fractionation. The short overall treatment time and low rates of acute toxicity make SBRT an optimal vehicle to integrate with novel systemic therapies, and several phase II studies have used concurrent cetuximab as a radiosensitizer with SBRT with promising results. Ongoing studies aim to evaluate the potential synergistic effect of SBRT with immune checkpoint inhibitors in recurrent head and neck cancer. PMID:27441751

  11. Clinical outcomes of stereotactic body radiotherapy for spinal metastases from hepatocellular carcinoma

    PubMed Central

    Lee, Eonju; Kim, Tae Gyu; Yu, Jeong Il; Lim, Do Hoon; Nam, Heerim; Lee, Hyebin; Lee, Joon Hyeok

    2015-01-01

    Purpose To investigate the outcomes of patients with spinal metastases from hepatocellular carcinoma (HCC), who were treated by stereotactic body radiotherapy (SBRT). Materials and Methods This retrospective study evaluated 23 patients who underwent SBRT from October 2008 to August 2012 for 36 spinal metastases from HCC. SBRT consisted of approximately 2 fractionation schedules, which were 18 to 40 Gy in 1 to 4 fractions for group A lesions (n = 15) and 50 Gy in 10 fractions for group B lesions (n = 21). Results The median follow-up period was 7 months (range, 2 to 16 months). Seven patients developed grade 1 or 2 gastrointestinal toxicity, and one developed grade 2 leucopenia. Compression fractures occurred in association with 25% of the lesions, with a median time to fracture of 2 months. Pain relief occurred in 92.3% and 68.4% of group A and B lesions, respectively. Radiologic response (complete and partial response) occurred in 80.0% and 61.9% of group A and B lesions, respectively. The estimated 1-year spinal-tumor progression-free survival rate was 78.5%. The median overall survival period and 1-year overall survival rate were 9 months (range, 2 to 16 months) and 25.7%, respectively. Conclusion SBRT for spinal metastases from HCC is well tolerated and effective at providing pain relief and radiologic response. Because compression fractures develop at a high rate following SBRT for spinal metastases from primary HCC, careful follow up of the patient is required. PMID:26484305

  12. Treatment of Primary Axillary Hyperhidrosis by Fractional Microneedle Radiofrequency: Is it Still Effective after Long-term Follow-up?

    PubMed Central

    Abtahi-Naeini, Bahareh; Naeini, Farahnaz Fatemi; Saffaei, Ali; Behfar, Shadi; Pourazizi, Mohsen; Mirmohammadkhani, Majid; Bolandnazar, Najmeh-Sadat

    2016-01-01

    Background: Primary axillary hyperhidrosis (PAH) is a chronic idiopathic disorder causing major stress in patients. Among the common therapies for PAH, only surgical interventions have proven feasible as a permanent solution. Objective and Aim: The aim of this study was to evaluate the efficacy and safety of fractional microneedle radiofrequency (FMR) as an alternative permanent treatment for PAH with long-term follow-up. Materials and Methods: This was a single-blind, sham-controlled comparative study. Twenty-five patients with severe PAH were provided three treatments of FMR at 3-week intervals (the treatment group), and a control group was provided the sham treatment. Clinical efficacy was evaluated using the hyperhidrosis disease severity scale (HDSS) at baseline and the end of the study, as well as during the 1 year follow-up phase. Results: HDSS demonstrated significant improvement after treatment in the treatment group compared to the sham control. The mean (±standard deviation) of HDSS in the group being treated with radiofrequency was 2.50 (±0.88) after 1 year follow-up, and that of the control group was 3.38 (±0.49; P < 0.001). Follow-up results show that there were 10 patients (41.6%) with no relapse and 11 patients (45.9%) with relapse after 1 year. There was a significant correlation between HDSS changes in relapse and body mass index (BMI) (P = 0.03). Conclusion: Treatment of PAH with FMR is a safe and noninvasive procedure with a positive therapeutic effect on HDSS. It is recommended, however, that sessions of FMR be repeated after 1 year, particularly in overweight patients with high BMIs. Clinical Trial Registration: IRCT2013111915455N1. Level of Evidences: Level II-1. PMID:27057039

  13. Emerging applications of stereotactic body radiotherapy.

    PubMed

    Lo, Simon S; Loblaw, Andrew; Chang, Eric L; Mayr, Nina A; Teh, Bin S; Huang, Zhibin; Yao, Min; Ellis, Rodney J; Biswas, Tithi; Sohn, Jason W; Machtay, Mitchell; Sahgal, Arjun

    2014-05-01

    Stereotactic body radiotherapy (SBRT) has been used extensively in patients with lung, liver and spinal tumors, and the treatment outcomes are very favorable. For certain conditions such as medically inoperable stage I non-small-cell lung cancer, liver and lung oligometastases, primary liver cancer and spinal metastases, SBRT is regarded as one of the standard therapies. In the recent years, the use of SBRT has been extended to other disease conditions and sites such as recurrent head and neck cancer, renal cell carcinoma, prostate cancer, adrenal metastasis, pancreatic cancer, gynecological malignancies, spinal cord compression, breast cancer, and stage II-III non-small-cell lung cancer. Preliminary data in the literature show promising results but the follow-up intervals are short for most studies. This paper will provide an overview of these emerging applications. PMID:24947266

  14. Stereotactic Radiation Therapy for Benign Meningioma: Long-Term Outcome in 318 Patients

    SciTech Connect

    Fokas, Emmanouil; Henzel, Martin; Surber, Gunar; Hamm, Klaus; Engenhart-Cabillic, Rita

    2014-07-01

    Purpose: To investigate the long-term outcome of stereotactic-based radiation therapy in a large cohort of patients with benign intracranial meningiomas. Methods and Materials: Between 1997 and 2010, 318 patients with histologically confirmed (44.7%; previous surgery) or imaging-defined (55.3%) benign meningiomas were treated with either fractionated stereotactic radiation therapy (79.6%), hypofractionated stereotactic radiation therapy (15.4%), or stereotactic radiosurgery (5.0%), depending on tumor size and location. Local control (LC), overall survival (OS), cause-specific survival (CSS), prognostic factors, and toxicity were analyzed. Results: The median follow-up was 50 months (range, 12-167 months). Local control, OS, and CSS at 5 years were 92.9%, 88.7%, and 97.2%, and at 10 years they were 87.5%, 74.1%, and 97.2%, respectively. In the multivariate analysis, tumor location (P=.029) and age >66 years (P=.031) were predictors of LC and OS, respectively. Worsening of pre-existing neurologic symptoms immediately after radiation therapy occurred in up to 2%. Clinically significant acute toxicity (grade 3°) occurred in 3%. Only grade 1-2 late toxicity was observed in 12%, whereas no new neurologic deficits or treatment-related mortality were encountered. Conclusions: Patients with benign meningiomas predominantly treated with standard fractionated stereotactic radiation therapy with narrow margins enjoy excellent LC and CSS, with minimal long-term morbidity.

  15. Gallotannin-rich Caesalpinia spinosa fraction decreases the primary tumor and factors associated with poor prognosis in a murine breast cancer model

    PubMed Central

    2013-01-01

    Background Several treatment alternatives are available for primary breast cancer, although those for metastatic disease or inflammation associated with tumor progression are ineffective. Therefore, there is a great need for new therapeutic alternatives capable of generating an immune response against residual tumor cells, thus contributing to eradication of micrometastases and cancer stem cells. The use of complex natural products is an excellent therapeutic alternative widely used by Chinese, Hindu, Egyptian, and ancestral Latin-American Indian populations. Methods The present study evaluated cytotoxic, antitumor, and tumor progression activities of a gallotannin-rich fraction derived from Caesalpinia spinosa (P2Et). The parameters evaluated in vitro were mitochondrial membrane depolarization, phosphatidylserine externalization, caspase 3 activation, DNA fragmentation, and clonogenic activity. The parameters evaluated in vivo were tumor growth, leukocyte number, metastatic cell number, and cytokine production by flow cytometry. Results The in vitro results showed that the P2Et fraction induced apoptosis with mitochondrial membrane potential loss, phosphatidylserine externalization, caspase 3 activation, DNA fragmentation, and decreased clonogenic capacity of 4T1 cells. In vivo, the P2Et fraction induced primary tumor reduction in terms of diameter and weight in BALB/c mice transplanted with 4T1 cells and decreased numbers of metastatic cells, mainly in the spleen. Furthermore, decreases in the number of peripheral blood leukocytes (leukemoid reaction) and interleukin 6 (IL-6) serum levels were found, which are events associated with a poor prognosis. The P2Et fraction exerts its activity on the primary tumor, reduces cell migration to distant organs, and decreases IL-6 serum levels, implying tumor microenvironment mechanisms. Conclusions Overall, the P2Et fraction lessens risk factors associated with tumor progression and diminishes primary tumor size, showing

  16. Repeated stereotactic body radiotherapy for oligometastatic prostate cancer recurrence

    PubMed Central

    2014-01-01

    Purpose To assess the outcome of prostate cancer (PCa) patients diagnosed with oligometastatic disease at recurrence and treated with stereotactic body radiotherapy (SBRT). Methods Non-castrate patients with up to 3 synchronous metastases (bone and/or lymph nodes) diagnosed on positron emission tomography - computed tomography, following biochemical recurrence after local curative treatment, were treated with (repeated) SBRT to a dose of 50 Gy in 10 fractions or 30 Gy in 3 fractions. Androgen deprivation therapy-free survival (ADT-FS) defined as the time interval between the first day of SBRT and the initiation of ADT was the primary endpoint. ADT was initiated if more than 3 metastases were detected during follow-up even when patients were still asymptomatic. Secondary endpoints were local control, progression free survival (PFS) and toxicity. Toxicity was scored using the Common Terminology Criteria for Adverse Events. Results With a median follow-up from time of SBRT of 2 years, we treated 50 patients with 70 metastatic lesions with a local control rate of 100%. The primary involved metastatic sites were lymph nodes (54%), bone (44%), and viscera (2%). The median PFS was 19 mo (95% CI: 13–25 mo) with 75% of recurring patients having ≤3 metastases. A 2nd and 3rd course of SBRT was delivered in 19 and 6 patients respectively. This results in a median ADT-FS of 25 months (20–30 mo). On univariate analysis, only a short PSA doubling time was a significant predictor for both PFS (HR: 0.90, 95% CI: 0.82 – 0.99) and ADT-FS (HR: 0.83; 95% CI: 0.71 – 0.97). Ten patients (20%) developed toxicity following treatment, which was classified as grade I in 7 and grade II in 3 patients. Conclusion Repeated SBRT for oligometastatic prostate cancer postpones palliative androgen deprivation therapy with 2 years without grade III toxicity. PMID:24920079

  17. Stereotactic radiosurgery - discharge

    MedlinePlus

    ... PA: Elsevier Saunders; 2012:chap 11. Read More Acoustic neuroma Brain tumor - primary - adults Cerebral arteriovenous malformation ... A.M. Editorial team. Related MedlinePlus Health Topics Acoustic Neuroma Arteriovenous Malformations Brain Tumors Childhood Brain Tumors ...

  18. Characterization of saccharides in size-fractionated ambient particulate matter and aerosol sources: the contribution of primary biological aerosol particles (PBAPs) and soil to ambient particulate matter.

    PubMed

    Jia, Yuling; Fraser, Matthew

    2011-02-01

    Size-fractionated (equivalent to ambient PM2.5 and PM10) local soil, plant, and spore samples were collected in the Sonoran Desert near Phoenix, AZ and measured for saccharide content with the goal of characterizing ambient particulate matter sources including soil and primary biological aerosol particles (PBAPs) from plants and fungi. Different saccharide compositions were observed among soil, plant, and spore samples and between PM2.5 and PM10 fractions. The total measured nonlevoglucosan saccharide content relative to PM mass in ambient aerosols collected in a Phoenix suburb (Higley) was much higher compared to the local soil samples but much lower compared to the PBAP. The enrichment of saccharides from two saccharide-dominated PM source factors resolved by a positive matrix factorization model is also higher than the saccharide content in the size-fractionated local soil samples, but lower than that measured in the size-segregated PBAP samples. This indicates that ambient concentration of particulate saccharides at Higley was dominated by contributions from PBAPs directly injected into the atmosphere from plants and spores rather than from soil and associated biota. Our results also suggest the contribution to the fine size fraction of ambient PM from the primary biologically derived sources may be greater than previously acknowledged. PMID:21214236

  19. Multifunctional T Lymphocytes Generated After Therapy With an Antitumor Gallotanin-Rich Normalized Fraction Are Related to Primary Tumor Size Reduction in a Breast Cancer Model.

    PubMed

    Urueña, Claudia; Gomez, Alejandra; Sandoval, Tito; Hernandez, John; Li, Shaoping; Barreto, Alfonso; Fiorentino, Susana

    2015-09-01

    Natural compounds are promising sources for anticancer therapies because of their multifunctional activity and low toxicity. Although the host immune response (IR) is clearly implicated in tumor control, the relationship between natural therapies and IR has not yet been elucidated. The present work evaluates IR induction after treatment with a gallotannin-rich fraction from Caesalpinia spinosa (P2Et). Breast tumor 4T1 cells were used to evaluate antitumor properties and IR activation. Apoptosis and expression of immunogenic cell death (ICD) markers were assessed in vitro, whereas IR and postvaccination tumor evolution were assessed in vivo. P2Et fraction induced apoptotic cell death, displaying phosphatidylserine externalization and DNA fragmentation. ICD markers such as calreticulin, high-mobility group box 1 translocation from nuclei to cytoplasm, and ATP secretion were observed. Primary tumor control was improved by vaccination with P2Et-pretreated 4T1 cells (t-P2Et), yielding long-lasting ex vivo multifunctional CD4(+) and CD8(+) T lymphocytes (interleukin [IL]-2(+), tumor necrosis factor [TNF]-α(+), interferon [IFN]-γ(+)) that secrete IL-2, TNF-α, IL-4, IL-5, and IFN-γ after specific 4T1 cell stimulation. The present study constitutes the first demonstration of a long-lasting antitumor IR induction and primary tumor reduction induced by a complex natural fraction. These data reveal the potential use of this fraction as an adjuvant in breast cancer treatment. PMID:26220604

  20. A phase I trial of stereotactic body radiation therapy (SBRT) for liver metastases

    SciTech Connect

    Schefter, Tracey E. . E-mail: Tracey.Schefter@uchsc.edu; Kavanagh, Brian D.; Timmerman, Robert D.; Cardenes, Higinia R.; Baron, Anna; Gaspar, Laurie E.

    2005-08-01

    Purpose: To determine the maximum tolerated dose (MTD) of stereotactic body radiation therapy (SBRT) for liver metastases. Methods and Materials: A multicenter Phase I clinical trial was conducted. Eligible patients had one to three liver metastases, tumor diameter <6 cm, and adequate liver function. The first cohort received 36 Gy to the planning target volume (PTV) in three fractions (F). Subsequent cohorts received higher doses up to a chosen maximum of 60 Gy/3F. At least 700 mL of normal liver had to receive a total dose <15 Gy. Dose-limiting toxicity (DLT) included acute Grade 3 liver or intestinal toxicity or any acute Grade 4 toxicity. The MTD was exceeded if 2/6 patients in a cohort experienced DLT. Results: Eighteen patients were enrolled (10 male, 8 female): median age, 55 years (range, 26-83 years); most common primary site, colorectal (6 patients); median aggregate gross tumor volume, 18 ml (range, 3-98 ml). Four patients had multiple tumors. No patient experienced a DLT, and dose was escalated to 60 Gy/3F without reaching MTD. Conclusions: Biologically potent doses of SBRT are well tolerated in patients with limited liver metastases. Results of this study form the basis for an ongoing Phase II SBRT study of 60 Gy over three fractions for liver metastases.

  1. Comparison of left ventricular ejection fraction and inducible ventricular tachycardia in ST-elevation myocardial infarction treated by primary angioplasty versus thrombolysis.

    PubMed

    Chong, James J H; Ganesan, Anand N; Eipper, Vicki; Kovoor, Pramesh

    2008-01-15

    Electrophysiologic studies predict the risk for sudden death after myocardial infarction (MI). Although primary angioplasty has become the preferred method of treatment for ST-elevation MI, intravenous thrombolysis remains the first-line treatment in 30% to 70% of cases worldwide. Rates of ventricular tachyarrhythmias may vary according to type of reperfusion treatment. This study was undertaken to examine the hypothesis that the left ventricular ejection fraction (LVEF) and rates of inducible ventricular tachycardia may be more favorable in treatment with primary angioplasty rather than thrombolysis. Consecutive patients receiving primary angioplasty (n = 225) or thrombolysis (n = 195) for ST-elevation MI were included. The mean LVEF was 48 +/- 12% for the primary angioplasty group and 46 +/- 13% for the thrombolysis group (p = 0.30). The proportion of patients with LVEFs <40% was 30% in the primary angioplasty group and 30% in the thrombolysis group (p = 0.98). Patients with LVEFs <40% underwent electrophysiologic studies. Ventricular tachycardia was inducible in 23 of 66 primary angioplasty patients (34.8%) compared with 21 of 55 (38.1%) thrombolysis patients (p = 0.69). Implantable cardiac defibrillators were inserted in 30 patients, of whom 8 (27%) had appropriate device activations. The mean time from MI to first spontaneous activation was 387 +/- 458 days. In conclusion, patients treated with thrombolysis or primary angioplasty for ST-elevation MIs had similar resultant LVEFs and rates of inducible ventricular tachycardia. There was a surprisingly high rate of spontaneous defibrillator activations, often occurring late after MI. PMID:18178398

  2. Vertebral Compression Fracture (VCF) After Spine Stereotactic Body Radiation Therapy (SBRT): Analysis of Predictive Factors

    SciTech Connect

    Cunha, Marcelo V.R.; Al-Omair, Ameen; Atenafu, Eshetu G.; Masucci, Giuseppina Laura; Letourneau, Daniel; Korol, Renee; Yu, Eugene; Howard, Peter; Lochray, Fiona; Costa, Leodante B. da; Fehlings, Michael G.; Sahgal, Arjun

    2012-11-01

    Purpose: Vertebral compression fractures (VCFs) are increasingly observed after spine stereotactic body radiation therapy (SBRT). The aim of this study was to determine the risk of VCF after spine SBRT and identify clinical and dosimetric factors predictive for VCF. The analysis incorporated the recently described Spinal Instability Neoplastic Score (SINS) criteria. Methods and Materials: The primary endpoint of this study was the development of a de novo VCF (ie, new endplate fracture or collapse deformity) or fracture progression based on an existing fracture at the site of treatment after SBRT. We retrospectively scored 167 spinal segments in 90 patients treated with spine SBRT according to each of the 6 SINS criteria. We also evaluated the presence of paraspinal extension, prior radiation, various dosimetric parameters including dose per fraction ({>=}20 Gy vs <20 Gy), age, and histology. Results: The median follow-up was 7.4 months. We identified 19 fractures (11%): 12 de novo fractures (63%) and 7 cases of fracture progression (37%). The mean time to fracture after SBRT was 3.3 months (range, 0.5-21.6 months). The 1-year fracture-free probability was 87.3%. Multivariate analysis confirmed that alignment (P=.0003), lytic lesions (P=.007), lung (P=.03) and hepatocellular (P<.0001) primary histologies, and dose per fraction of 20 Gy or greater (P=.004) were significant predictors of VCF. Conclusions: The presence of kyphotic/scoliotic deformity and the presence of lytic tumor were the only predictive factors of VCF based on the original 6 SINS criteria. We also report that patients with lung and hepatocellular tumors and treatment with SBRT of 20 Gy or greater in a single fraction are at a higher risk of VCF.

  3. Stereotactic Body Radiation Therapy in Spinal Metastases

    SciTech Connect

    Ahmed, Kamran A.; Stauder, Michael C.; Miller, Robert C.; Bauer, Heather J.; Rose, Peter S.; Olivier, Kenneth R.; Brown, Paul D.; Brinkmann, Debra H.; Laack, Nadia N.

    2012-04-01

    Purpose: Based on reports of safety and efficacy, stereotactic body radiotherapy (SBRT) for treatment of malignant spinal tumors was initiated at our institution. We report prospective results of this population at Mayo Clinic. Materials and Methods: Between April 2008 and December 2010, 85 lesions in 66 patients were treated with SBRT for spinal metastases. Twenty-two lesions (25.8%) were treated for recurrence after prior radiotherapy (RT). The mean age of patients was 56.8 {+-} 13.4 years. Patients were treated to a median dose of 24 Gy (range, 10-40 Gy) in a median of three fractions (range, 1-5). Radiation was delivered with intensity-modulated radiotherapy (IMRT) and prescribed to cover 80% of the planning target volume (PTV) with organs at risk such as the spinal cord taking priority over PTV coverage. Results: Tumor sites included 48, 22, 12, and 3 in the thoracic, lumbar, cervical, and sacral spine, respectively. The mean actuarial survival at 12 months was 52.2%. A total of 7 patients had both local and marginal failure, 1 patient experienced marginal but not local failure, and 1 patient had local failure only. Actuarial local control at 1 year was 83.3% and 91.2% in patients with and without prior RT. The median dose delivered to patients who experienced local/marginal failure was 24 Gy (range, 18-30 Gy) in a median of three fractions (range, 1-5). No cases of Grade 4 toxicity were reported. In 1 of 2 patients experiencing Grade 3 toxicity, SBRT was given after previous radiation. Conclusion: The results indicate SBRT to be an effective measure to achieve local control in spinal metastases. Toxicity of treatment was rare, including those previously irradiated. Our results appear comparable to previous reports analyzing spine SBRT. Further research is needed to determine optimum dose and fractionation to further improve local control and prevent toxicity.

  4. Patient barriers to implantable cardioverter defibrillator implantation for the primary prevention of sudden cardiac death in patients with heart failure and reduced ejection fraction

    PubMed Central

    Chan, Laura Lihua; Lim, Choon Pin; Aung, Soe Tin; Quetua, Paul; Ho, Kah Leng; Chong, Daniel; Teo, Wee Siong; Sim, David; Ching, Chi Keong

    2016-01-01

    INTRODUCTION Device therapy is efficacious in preventing sudden cardiac death (SCD) in patients with reduced ejection fraction. However, few who need the device eventually opt to undergo implantation and even fewer reconsider their decisions after deliberation. This is due to many factors, including unresolved patient barriers. This study identified the factors that influenced patients’ decision to decline implantable cardioverter defibrillator (ICD) implantation, and those that influenced patients who initially declined an implant to reconsider having one. METHODS A single-centre survey was conducted among 240 patients who had heart failure with reduced ejection fraction and met the ICD implantation criteria, but had declined ICD implantation. RESULTS Participants who refused ICD implantation were mostly male (84%), Chinese (71%), married (72%), currently employed (54%), and had up to primary or secondary education (78%) and monthly income of < SGD 3,000 (51%). Those who were more likely to reconsider their decision were aware that SCD was a consequence of heart failure with reduced ejection fraction, knowledgeable of the preventive role of ICDs, currently employed and aware that their doctor strongly recommended the implant. Based on multivariate analysis, knowledge of the role of ICDs for primary prophylaxis was the most important factor influencing patient decision. CONCLUSION This study identified the demographic and social factors of patients who refused ICD therapy. Knowledge of the role of ICDs in preventing SCD was found to be the strongest marker for reconsidering ICD implantation. Measures to address this information gap may lead to higher rates of ICD implantation. PMID:27075476

  5. Differential protection among fractionated blueberry polyphenolic families against DA-, Aβ42 and LPS-induced decrements in Ca2+ buffering in primary hippocampal cells

    PubMed Central

    Joseph, James A.; Shukitt-Hale, Barbara; Brewer, Gregory J.; Weikel, Karen A.; Kalt, Wilhelmina; Fisher, Derek R.

    2011-01-01

    It has been postulated that at least part of the loss of cognitive function in aging may be the result of deficits in Ca2+ recovery (CAR) and increased oxidative/inflammatory (OX/INF) stress signaling. However, previous research showed that aged animals supplemented with blueberry (BB) extract, showed fewer deficits in CAR, as well as motor and cognitive functional deficits. A recent subsequent experiment has shown that DA- or Aβ42-induced deficits in CAR in primary hippocampal neuronal cells (HNC) were antagonized by BB extract, and (OX/INF) signaling was reduced. Present experiments assessed the most effective BB polyphenol fraction that could protect against OX/INF-induced deficits in CAR, ROS generation, or viability. HNCs treated with BB extract, BB fractions (e.g., proanthocyanidin, PAC), or control medium were exposed to dopamine (DA, 0.1mM), amyloid beta (Aβ42, 25 µM) or lipopolysaccharide (LPS, 1µg/ml). Results indicated that the degree of protection against deficits in CAR varied as a function of the stressor and was generally greater against Aβ42 and LPS than DA. The whole BB, anthocyanin (ANTH) and pre-C18 fractions offered the greatest protection, while chlorogenic acid offered the lowest protection. Protective capabilities of the various fractions against ROS depended upon the stressor, where the BB extract and the combined PAC (high and low m.w.) fraction offered the best protection against LPS and Aβ42 but were less effective against DA-induced ROS. The high and low m.w. PACs and the ANTH fractions enhanced ROS production regardless of the stressor used and this reflected increased activation of stress signals (e.g., P38 MAPK). The viability data indicated that the whole BB and combined PAC fraction showed greater protective effects against the stressors than the more fractionated polyphenolic components. Thus, these results suggest that, except for a few instances, the lesser the polyphenolic fractionation the greater the effects, especially

  6. Carbon-Isotope Fractionations of Autotrophic Bacteria: Relevance to Primary Production and Microbial Evolution in Hot Springs and Hydrothermal Vents

    NASA Astrophysics Data System (ADS)

    Zhang, C. L.; Romanek, C. S.; Mills, G.

    2004-12-01

    Terrestrial hot springs and marine hydrothermal vents are often dominated by autotrophic microorganisms. Species of the Bacteria Domain in these environments are known to use different pathways for CO2 fixation. These may include the Calvin cycle, the Acetyl CoA pathway, the reverse TCA cycle, and the 3-HP pathway. Each cycle or pathway may be characterized by distinct patterns of carbon isotope fractionation. This presentation will summarize isotope fractionation patterns associated with known autotrophic bacteria and to use these patterns for interpreting natural isotopic variations. Examples will include hot springs from the Yellowstone National Park and Nevada desert, USA and Kamchatka, Russia, and hydrothermal vents from the East Pacific Rise. An attempt will be made to discuss isotopic variations within a particular pathway in the context of species evolution through horizontal gene transfer.

  7. A primary experience of conventional fractionated three-dimensional conformal partial breast irradiation for early-stage breast cancer

    PubMed Central

    LIAO, LINGXIA; HAN, GUANG; LI, YANPING; WANG, ZHAOHUA; LIU, DONG; PI, ZHENGCHAO

    2011-01-01

    Recently, a number of clinical trials assessing partial breast irradiation (PBI), in particular accelerated partial breast irradiation, have been conducted in patients with early-stage breast cancer after breast-conserving surgery (BCS) in Europe and the US. By contrast, PBI is rarely performed in Eastern countries. In general, there are many physiological differences between Eastern and Western populations, and whether PBI is suitable for Eastern populations remains uncertain. Moreover, PBI is still in the stage of clinical research, and numerous questions have yet to be resolved. Thus, we designed a PBI trial to explore its feasibility and effectiveness for Eastern patients. According to the study criteria, 12 patients were enrolled between June 2003 and March 2007. Using three-dimensional conformal partial breast irradiation, they received a conventional fraction of 2 Gy/fraction/day, 5 fractions/week, DT60 Gy. According to follow-up data collected in August 2010, the rates of local recurrence and distant metastasis were 0%. The most common adverse reactions included grade 2 radioactive erythema in 2 (17%) cases and pigment deposition in 10 (83%). The results revealed that the patients exhibited good local tumor control, with minor adverse reactions and satisfactory cosmetic results. More samples and long-term observations are required to further assess the validity and feasibility of PBI. PMID:22977539

  8. Stereotactic proton beam therapy for intracranial arteriovenous malformations

    SciTech Connect

    Vernimmen, Frederik J.A.I. . E-mail: fv@sun.ac.za; Slabbert, Jacobus P.; Wilson, Jennifer A.; Fredericks, Shaheeda

    2005-05-01

    Purpose: To investigate hypofractionated stereotactic proton therapy of predominantly large intracranial arteriovenous malformations (AVMs) by analyzing retrospectively the results from a cohort of patients. Methods and Materials: Since 1993, a total of 85 patients with vascular lesions have been treated. Of those, 64 patients fulfilled the criteria of having an arteriovenous malformation and sufficient follow-up. The AVMs were grouped by volume: <14 cc (26 patients) and {>=}14 cc (38 patients). Treatment was delivered with a fixed horizontal 200 MeV proton beam under stereotactic conditions, using a stereophotogrammetric positioning system. The majority of patients were hypofractionated (2 or 3 fractions), and the proton doses are presented as single-fraction equivalent cobalt Gray equivalent doses (SFEcGyE). The overall mean minimum target volume dose was 17.37 SFEcGyE, ranging from 10.38-22.05 SFEcGyE. Results: Analysis by volume group showed obliteration in 67% for volumes <14 cc and 43% for volumes {>=}14 cc. Grade IV acute complications were observed in 3% of patients. Transient delayed effects were seen in 15 patients (23%), becoming permanent in 3 patients. One patient also developed a cyst 8 years after therapy. Conclusions: Stereotactic proton beam therapy applied in a hypofractionated schedule allows for the safe treatment of large AVMs, with acceptable results. It is an alternative to other treatment strategies for large AVMs. AVMs are likely not static entities, but probably undergo vascular remodeling. Factors influencing angiogenesis could play a new role in a form of adjuvant therapy to improve on the radiosurgical results.

  9. Stereotactic hypothalamotomy for behaviour disorders

    PubMed Central

    Schvarcz, J. R.; Driollet, R.; Rios, E.; Betti, O.

    1972-01-01

    Posterior hypothalamotomy is a relatively simple stereotactic procedure. The radiological determination of the target and its physiological corroboration by electrical stimulation are accurate. The lesions have always been made in the site of maximum sympathetic response. In this respect, the cardiovascular changes (hypertension and tachycardia), which are always elicited from a more restricted area, are of particular importance. Depth recordings, however, have been less useful. Undesirable side-effects, if present, were mild and transitory. There was no postoperative intelligence deficit, at least with the standard tests. Images PMID:5035309

  10. A Pilot Study of Hypofractionated Stereotactic Radiation Therapy and Sunitinib in Previously Irradiated Patients With Recurrent High-Grade Glioma

    SciTech Connect

    Wuthrick, Evan J.; Curran, Walter J.; Camphausen, Kevin; Lin, Alexander; Glass, Jon; Evans, James; Andrews, David W.; Axelrod, Rita; Shi, Wenyin; Werner-Wasik, Maria; Haacke, E. Mark; Hillman, Gilda G.; Dicker, Adam P.

    2014-10-01

    Purpose/Objective(s): Angiogenic blockade with irradiation may enhance the therapeutic ratio of radiation therapy (RT) through vascular normalization. We sought to determine the safety and toxicity profile of continuous daily-dosed sunitinib when combined with hypofractionated stereotactic RT (fSRT) for recurrent high-grade gliomas (rHGG). Methods and Materials: Eligible patients had malignant high-grade glioma that recurred or progressed after primary surgery and RT. All patients received a minimum of a 10-day course of fSRT, had World Health Organization performance status of 0 to 1, and a life expectancy of >3 months. During fSRT, sunitinib was administered at 37.5 mg daily. The primary endpoint was acute toxicity, and response was assessed via serial magnetic resonance imaging. Results: Eleven patients with rHGG were enrolled. The fSRT doses delivered ranged from 30 to 42 Gy in 2.5- to 3.75-Gy fractions. The median follow-up time was 40 months. Common acute toxicities included hematologic disorders, fatigue, hypertension, and elevated liver transaminases. Sunitinib and fSRT were well tolerated. One grade 4 mucositis toxicity occurred, and no grade 4 or 5 hypertensive events or intracerebral hemorrhages occurred. One patient had a nearly complete response, and 4 patients had stable disease for >9 months. Two patients (18%) remain alive and progression-free >3 years from enrollment. The 6-month progression-free survival was 45%. Conclusions: Sunitinib at a daily dose of 37.5 mg given concurrently with hypofractionated stereotactic reirradiation for rHGG yields acceptable toxicities and an encouraging 6-month progression-free survival.

  11. Stereotactic LINAC-Radiosurgery for Glomus Jugulare Tumors: A Long-Term Follow-Up of 27 Patients

    PubMed Central

    El Majdoub, Faycal; Hunsche, Stefan; Igressa, Alhadi; Kocher, Martin; Sturm, Volker; Maarouf, Mohammad

    2015-01-01

    Background The optimal treatment of glomus jugulare tumors (GJTs) remains controversial. Due to the critical location, microsurgery still provides high treatment-related morbidity and a decreased quality of life. Thus, we performed stereotactical radiosurgery (SRS) for the treatment of GJTs and evaluated the long-term outcome. Methods Between 1991 and 2011, 32 patients with GJTs underwent SRS using a linear accelerator (LINAC) either as primary or salvage therapy. Twenty-seven patients (median age 59.9 years, range 28.7–79.9 years) with a follow-up greater than five years (median 11 years, range 5.3–22.1 years) were selected for retrospective analysis. The median therapeutic single dose applied to the tumor surface was 15 Gy (range 11–20 Gy) and the median tumor volume was 9.5 ml (range 2.8–51 ml). Results Following LINAC-SRS, 10 of 27 patients showed a significant improvement of their previous neurological complaints, whereas 12 patients remained unchanged. Five patients died during follow-up due to old age or other, not treatment-related reasons. MR-imaging showed a partial remission in 12 and a stable disease in 15 patients. No tumor progression was observed. The actuarial overall survival rates after five, ten and 20 years were 100%, 95.2% and 79.4%, respectively. Conclusions Stereotactic LINAC-Radiosurgery can achieve an excellent long-term tumor control beside a low rate of morbidity in the treatment of GJTs. It should be considered as an alternative therapy regime to surgical resection or fractionated external beam radiation either as primary, adjuvant or salvage therapy. PMID:26069957

  12. CT Perfusion Imaging as an Early Biomarker of Differential Response to Stereotactic Radiosurgery in C6 Rat Gliomas

    PubMed Central

    Yeung, Timothy Pok Chi; Kurdi, Maher; Wang, Yong; Al-Khazraji, Baraa; Morrison, Laura; Hoffman, Lisa; Jackson, Dwayne; Crukley, Cathie; Lee, Ting-Yim; Bauman, Glenn; Yartsev, Slav

    2014-01-01

    Background The therapeutic efficacy of stereotactic radiosurgery for glioblastoma is not well understood, and there needs to be an effective biomarker to identify patients who might benefit from this treatment. This study investigated the efficacy of computed tomography (CT) perfusion imaging as an early imaging biomarker of response to stereotactic radiosurgery in a malignant rat glioma model. Methods Rats with orthotopic C6 glioma tumors received either mock irradiation (controls, N = 8) or stereotactic radiosurgery (N = 25, 12 Gy in one fraction) delivered by Helical Tomotherapy. Twelve irradiated animals were sacrificed four days after stereotactic radiosurgery to assess acute CT perfusion and histological changes, and 13 irradiated animals were used to study survival. Irradiated animals with survival >15 days were designated as responders while those with survival ≤15 days were non-responders. Longitudinal CT perfusion imaging was performed at baseline and regularly for eight weeks post-baseline. Results Early signs of radiation-induced injury were observed on histology. There was an overall survival benefit following stereotactic radiosurgery when compared to the controls (log-rank P<0.04). Responders to stereotactic radiosurgery showed lower relative blood volume (rBV), and permeability-surface area (PS) product on day 7 post-stereotactic radiosurgery when compared to controls and non-responders (P<0.05). rBV and PS on day 7 showed correlations with overall survival (P<0.05), and were predictive of survival with 92% accuracy. Conclusions Response to stereotactic radiosurgery was heterogeneous, and early selection of responders and non-responders was possible using CT perfusion imaging. Validation of CT perfusion indices for response assessment is necessary before clinical implementation. PMID:25329655

  13. Intake fractions of primary conserved air pollutants emitted from on-road vehicles in the United States

    NASA Astrophysics Data System (ADS)

    Lobscheid, Agnes B.; Nazaroff, William W.; Spears, Michael; Horvath, Arpad; McKone, Thomas E.

    2012-12-01

    Vehicular air pollutant emissions are characterized by a high degree of spatial variability that is correlated with the distribution of people. The consequences of the spatial association between emissions and exposed populations have not been fully captured in lifecycle and other impact assessments. The intake fraction (iF) quantifies aggregate air-pollutant exposures attributable to sources. Utilizing source-receptor (S-R) relationships derived from the US Environmental Protection Agency's AERMOD steady-state plume model, we quantify the intake fraction of conserved pollutants emitted from on-road mobile sources and report here the first characterization across approximately 65,000 census tracts of the conterminous United States. Considering exposures out to 50 km from the source, the population-weighted mean iF is 8.6 parts per million (ppm). The population-weighted median generally increases with geographic scale, from 3.6 ppm for census tracts to 4.2 ppm for counties, and 5.1 ppm for states, while the population-weighted interquartile range (IQR) progressively narrows as geographic scale increases: 0.85-8.8 ppm for census tracts, 1.5-8.5 ppm for counties, and 3.2-7.5 ppm for states. Across the four US Census regions, the population weighted median iF varies from 2.2 ppm (South) to 7.5 ppm (West), and the census-tract IQR spans an order of magnitude in each region (2.1-17 ppm in the West; 0.55-6.9 ppm in the Midwest; 0.45-5.5 ppm in the South; and 1.8-18 ppm in the Northeast). The population-weighted mean intake fraction for populous urban counties is about two orders of magnitude greater than for sparsely populated rural counties. On a population-weighted average basis and considering the 50 km analysis range, 75% of the intake occurs in the same county as emissions.

  14. Stereotactic radiotherapy and radiosurgery for non-functioning and secreting pituitary adenomas.

    PubMed

    Minniti, Giuseppe; Clarke, Enrico; Scaringi, Claudia; Enrici, Riccardo Maurizi

    2016-01-01

    Radiotherapy (RT) is frequently employed in patients with residual or recurrent pituitary adenoma with excellent rates of tumor control and remission of hormonal hypersecretion. Advances in RT have improved with the use of stereotactic techniques either as fractionated stereotactic radiotherapy (FSRT) or stereotactic radiosurgery (SRS), all aiming to improve the dose distribution to the tumor while reducing the amount of normal brain receiving significant doses of radiation. We provide an overview of the recent published literature on the long-term efficacy and adverse effects of stereotactic irradiation in nonfunctioning and secreting pituitary adenomas. Both techniques are associated with excellent clinical outcomes; however, advantages and drawbacks of each of these techniques in terms of local control, hormonal excess normalization, and radiation-induced toxicity remain a matter of debate. In clinical practice, single-fraction SRS may represent a convenient approach to patients with small and medium-sized pituitary adenoma away at least 2 mm from the optic chiasm, whereas FSRT is preferred over SRS for lesions >2.5-3 cm in size and/or involving the anterior optic pathway. PMID:27330422

  15. Stereotactic Body Radiotherapy (SBRT) for Intrahepatic and Hilar Cholangiocarcinoma

    PubMed Central

    Mahadevan, Anand; Dagoglu, Nergiz; Mancias, Joseph; Raven, Kristin; Khwaja, Khalid; Tseng, Jennifer F; Ng, Kimmie; Enzinger, Peter; Miksad, Rebecca; Bullock, Andrea; Evenson, Amy

    2015-01-01

    Background: Unresectable intrahepatic and hilar cholangiocarcinomas carry a dismal prognosis. Systemic chemotherapy and conventional external beam radiation and brachytherapy have been used with limited success. We explored the use of stereotactic body radiotherapy (SBRT) for these patients. Methods: Patients with unresectable intrahepatic or hilar cholangiocarcinoma or those with positive margins were included in this study. Systemic therapy was used at the discretion of the medical oncologist. The CyberknifeTM stereotactic body radiotherapy system used to treat these patients. Patients were treated with three daily fractions. Clinical and radiological follow-up were performed every three months. Results: 34 patients (16 male and 18 female) with 42 lesions were included in this study. There were 32 unresectable tumors and two patients with resected tumors with positive margins. The median SBRT dose was 30Gy in three fractions. The median follow-up was 38 months (range 8-71 months). The actuarial local control rate was 79%. The median overall survival was 17 months and the median progression free survival was ten months. There were four Grade III toxicities (12%), including duodenal ulceration, cholangitis and liver abscess. Conclusions: SBRT is an effective and reasonably safe local therapy option for unresectable intrahepatic or hilar cholangiocarcinoma. PMID:26516357

  16. Uncovering heart failure with preserved ejection fraction in patients with type 2 diabetes in primary care: time for a change.

    PubMed

    Boonman-de Winter, L J M; Cramer, M J; Hoes, A W; Rutten, F H

    2016-04-01

    Undetected heart failure appears to be an important health problem in patients with type 2 diabetes and aged ≥ 60 years. The prevalence of previously unknown heart failure in these patients is high, steeply rises with age, and is overall higher in women than in men. The majority of the patients with newly detected heart failure have a preserved ejection fraction. A diagnostic algorithm to detect or exclude heart failure in these patients with variables from the medical files combined with items from history taking and physical examination provides a good to excellent accuracy. Annual screening appears to be cost-effective. Both unrecognised heart failure with reduced and with preserved ejection fraction were associated with a clinically relevant lower health status in patients with type 2 diabetes. Also the prognosis of these patients was worse than of those without heart failure. Existing disease-management programs for type 2 diabetes pay insufficient attention to early detection of cardiovascular diseases, including heart failure. We conclude that more attention is needed for detection of heart failure in older patients with type 2 diabetes. PMID:26905581

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

    SciTech Connect

    Wang Xin; Liu Xiaoxia; Mei Guanghai; Dai Jiazhong; Pan Li; Wang Enmin

    2012-06-01

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

  18. Tumor Volume-Adapted Dosing in Stereotactic Ablative Radiotherapy of Lung Tumors

    SciTech Connect

    Trakul, Nicholas; Chang, Christine N.; Harris, Jeremy; Chapman, Christopher; Rao, Aarti; Shen, John; Quinlan-Davidson, Sean; Filion, Edith J.; Wakelee, Heather A.; Colevas, A. Dimitrios; Whyte, Richard I.; and others

    2012-09-01

    Purpose: Current stereotactic ablative radiotherapy (SABR) protocols for lung tumors prescribe a uniform dose regimen irrespective of tumor size. We report the outcomes of a lung tumor volume-adapted SABR dosing strategy. Methods and Materials: We retrospectively reviewed the outcomes in 111 patients with a total of 138 primary or metastatic lung tumors treated by SABR, including local control, regional control, distant metastasis, overall survival, and treatment toxicity. We also performed subset analysis on 83 patients with 97 tumors treated with a volume-adapted dosing strategy in which small tumors (gross tumor volume <12 mL) received single-fraction regimens with biologically effective doses (BED) <100 Gy (total dose, 18-25 Gy) (Group 1), and larger tumors (gross tumor volume {>=}12 mL) received multifraction regimens with BED {>=}100 Gy (total dose, 50-60 Gy in three to four fractions) (Group 2). Results: The median follow-up time was 13.5 months. Local control for Groups 1 and 2 was 91.4% and 92.5%, respectively (p = 0.24) at 12 months. For primary lung tumors only (excluding metastases), local control was 92.6% and 91.7%, respectively (p = 0.58). Regional control, freedom from distant metastasis, and overall survival did not differ significantly between Groups 1 and 2. Rates of radiation pneumonitis, chest wall toxicity, and esophagitis were low in both groups, but all Grade 3 toxicities developed in Group 2 (p = 0.02). Conclusion: A volume-adapted dosing approach for SABR of lung tumors seems to provide excellent local control for both small- and large-volume tumors and may reduce toxicity.

  19. Feasibility and early clinical assessment of flattening filter free (FFF) based stereotactic body radiotherapy (SBRT) treatments

    PubMed Central

    2011-01-01

    Purpose To test feasibility and safety of clinical usage of Flattening Filter Free (FFF) beams for delivering ablative stereotactic body radiation therapy (SBRT) doses to various tumor sites, by means of Varian TrueBeam™ (Varian Medical Systems). Methods and Materials Seventy patients were treated with SBRT and FFF: 51 lesions were in the thorax (48 patients),10 in the liver, 9 in isolated abdominal lymph node, adrenal gland or pancreas. Doses ranged from 32 to 75 Gy, depending on the anatomical site and the volume of the lesion to irradiate. Lung lesions were treated with cumulative doses of 32 or 48 Gy, delivered in 4 consecutive fractions. The liver patients were treated in 3 fractions with total dose of 75 Gy. The isolated lymph nodes were irradiated in 6 fractions with doses of 45 Gy. The inclusion criteria were the presence of isolated node, or few lymph nodes in the same lymph node region, in absence of other active sites of cancer disease before the SBRT treatment. Results All 70 patients completed the treatment. The minimum follow-up was 3 months. Six cases of acute toxicities were recorded (2 Grade2 and 2 Grade3 in lung and 2 Grade2 in abdomen). No patient experienced acute toxicity greater than Grade3. No other types or grades of toxicities were observed at clinical evaluation visits. Conclusions This study showed that, with respect to acute toxicity, SBRT with FFF beams showed to be a feasible technique in 70 consecutive patients with various primary and metastatic lesions in the body. PMID:21910868

  20. Springtime size-fractionated primary production across hydrographic and PAR-light gradients in Chilean Patagonia (41-50°S)

    NASA Astrophysics Data System (ADS)

    Jacob, Bárbara G.; Tapia, Fabián J.; Daneri, Giovanni; Iriarte, Jose L.; Montero, Paulina; Sobarzo, Marcus; Quiñones, Renato A.

    2014-12-01

    We combined on-deck and in situ measurements and satellite-derived data to study the spatial variability of springtime size-fractionated primary production and chlorophyll-a biomass along gradients of hydrographic conditions and surface PAR in central and northern Chilean Patagonia (41-50°S). This extensive and fragmented region encompasses numerous fjords and channels, as well as the northern and southern icefields (46-47°S, 48-52°S). Primary production displayed a latitudinal pattern decreasing southwards (6-fold lower), particularly toward areas influenced by rivers with a nival regime. Micro-phytoplankton (>20 μm) dominated the primary production (57-93%) and chlorophyll-a (43-91%) of northern sites, where warmer and more saline surface waters exhibit greater PAR irradiance. Small phytoplankton cells (<2 μm; 2-20 μm) contributed > 50% of carbon fixation and chlorophyll-a in the southernmost sites, especially those located near glaciers and major rivers, where surface temperature, salinity, and PAR irradiance were lowest. The long-term (2002-2012) average field of springtime PAR derived from satellite imagery showed a southward increase in longitudinal gradients, which indicates that spatial changes in surface light attenuation along this region are largely driven by glacier-derived freshwater inputs. A principal component analysis of surface temperature, salinity, and PAR produced an ordination of sites that was consistent with spatial changes in the balance of oceanic versus riverine influence on surface conditions along this region. Total primary production was significantly correlated (r = 0.61, p = 0.007) with the first principal component, which explained 65% of joint variability in hydrographic conditions and PAR. The same principal component clearly separated sites in northern Patagonia where micro-phytoplankton dominated total primary production - along the Reloncavi fjord and Inner Sea of Chiloe - from those located further south where other size

  1. Stereotactic Body Radiation Therapy for Patients With Lung Cancer Previously Treated With Thoracic Radiation

    SciTech Connect

    Kelly, Patrick; Balter, Peter A.; Rebueno, Neal; Sharp, Hadley J.; Liao Zhongxing; Komaki, Ritsuko; Chang, Joe Y.

    2010-12-01

    Purpose: Stereotactic body radiation therapy (SBRT) provides excellent local control with acceptable toxicity for patients with early-stage non-small cell lung cancer. However, the efficacy and safety of SBRT for patients previously given thoracic radiation therapy is not known. In this study, we retrospectively reviewed outcomes after SBRT for recurrent disease among patients previously given radiation therapy to the chest. Materials and Methods: A search of medical records for patients treated with SBRT to the thorax after prior fractionated radiation therapy to the chest at The University of Texas M. D. Anderson Cancer Center revealed 36 such cases. The median follow-up time after SBRT was 15 months. The endpoints analyzed were overall survival, local control, and the incidence and severity of treatment-related toxicity. Results: SBRT provided in-field local control for 92% of patients; at 2 years, the actuarial overall survival rate was 59%, and the actuarial progression-free survival rate was 26%, with the primary site of failure being intrathoracic relapse. Fifty percent of patients experienced worsening of dyspnea after SBRT, with 19% requiring oxygen supplementation; 30% of patients experienced chest wall pain and 8% Grade 3 esophagitis. No Grade 4 or 5 toxic effects were noted. Conclusions: SBRT can provide excellent in-field tumor control in patients who have received prior radiation therapy. Toxicity was significant but manageable. The high rate of intrathoracic failure indicates the need for further study to identify patients who would derive the most benefit from SBRT for this purpose.

  2. Linac-based stereotactic radiotherapy and radiosurgery in patients with meningioma

    PubMed Central

    2014-01-01

    Background It was our purpose to analyze long-term clinical outcome and to identify prognostic factors after Linac-based fractionated stereotactic radiotherapy (Linac-based FSRT) and stereotactic radiosurgery (SRS) in patients with intracranial meningiomas. Materials and methods Between 10/1995 and 03/2009, 297 patients with a median age of 59 years were treated with FSRT for intracranial meningioma. 50 patients had a Grade I meningioma, 20 patients had a Grade II meningioma, 12 patients suffered from a Grade III tumor, and in 215 cases no histology was obtained (Grade 0). Of the 297 patients, 144 underwent FSRT as their primary treatment and 158 underwent postoperative FSRT. 179 patients received normofractionated radiotherapy (nFSRT), 92 patients received hypofractionated FSRT (hFSRT) and 26 patients underwent SRS. Patients with nFSRT received a mean total dose of 57.31 ± 5.82 Gy, patients with hFSRT received a mean total dose of 37.6 ± 4.4 Gy and patients who underwent SRS received a mean total dose of 17.31 ± 2.58 Gy. Results Median follow-up was 35 months. Overall progression free survival (PFS) was 92.3% at 3 years, 87% at 5 years and 84.1% at 10 years. Patients with adjuvant radiotherapy showed significantly better PFS-rates than patients who had been treated with primary radiotherapy. There was no significant difference between PFS-rates of nFSRT, hFSRT and SRS patients. PFS-rates were independent of tumor size. Patients who had received nFSRT showed less acute toxicity than those who had received hFSRT. In the Grade 0/I group the rate of radiologic focal reactions was significantly lower than in the atypical/malignant histology group. Conclusion This large study showed that FSRT is an effective and safe treatment modality with high PFS-rates for intracranial meningioma. We identified “pathological grading” and and “prior surgery” as significant prognostic factors. PMID:24650090

  3. Stereotactic Body Radiation Therapy for Oligometastases to the Lung: A Phase 2 Study

    SciTech Connect

    Nuyttens, Joost J.; Voort van Zyp, Noëlle C.M.G. van der; Verhoef, Cornelis; Maat, A.; Klaveren, Robertus J. van; Holt, Bronno van der; Aerts, Joachim; Hoogeman, Mischa

    2015-02-01

    Purpose: To assess, in a phase 2 study, the efficacy and toxicity of stereotactic body radiation therapy for oligometastases to the lung in inoperable patients. Methods and Materials: Patients with lung metastases were included in this study if (1) the primary tumor was controlled; (2) patients were ineligible for or refused surgery and chemotherapy; and (3) patients had 5 or fewer metastatic lesions in no more than 2 organs. Large peripheral tumors were treated with a dose of 60 Gy (3 fractions), small peripheral tumors with 30 Gy (1 fraction), central tumors received 60 Gy (5 fractions), and mediastinal tumors or tumors close to the esophagus received 56 Gy (7 fractions). Results: Thirty patients with 57 metastatic lung tumors from various primary cancers were analyzed. The median follow-up was 36 months (range, 4-60 months). At 2 years, local control for the 11 central tumors was 100%, for the 23 peripheral tumors treated to 60 Gy it was 91%, and for the 23 tumors treated in a single 30-Gy fraction it was 74% (P=.13). This resulted in an overall local control rate at 1 year of 79%, with a 2-sided 80% confidence interval of 67% to 87%. Because the hypothesized value of 70% lies within the confidence interval, we cannot reject the hypothesis that the true local control rate at 1 year is ≤70%, and therefore we did not achieve the goal of the study: an actuarial local control of the treated lung lesions at 1 year of 90%. The 4-year overall survival rate was 38%. Grade 3 acute toxicity occurred in 5 patients. Three patients complained of chronic grade 3 toxicity, including pain, fatigue, and pneumonitis, and 3 patients had rib fractures. Conclusions: The local control was promising, and the 4-year overall survival rate was 38%. The treatment was well tolerated, even for central lesions.

  4. Stereotactic radiotherapy of meningiomas compressing optical pathways

    SciTech Connect

    Hamm, Klaus-Detlef . E-mail: khamm@erfurt.helios-kliniken.de; Henzel, Martin; Gross, Markus W.; Surber, Gunnar; Kleinert, Gabriele; Engenhart-Cabillic, Rita

    2006-11-15

    Purpose: Microsurgical resection is usually the treatment of choice for meningiomas, especially for those that compress the optical pathways. However, in many cases of skull-base meningiomas a high risk of neurological deficits and recurrences exist in cases where the complete tumor removal was not possible. In such cases (fractionated) stereotactic radiotherapy (SRT) can offer an alternative treatment option. We evaluated the local control rate, symptomatology, and toxicity. Patients and Methods: Between 1997 and 2003, 183 patients with skull-base meningiomas were treated with SRT, among them were 65 patients with meningiomas that compressed optical pathways (64 benign, 1 atypical). Of these 65 cases, 20 were treated with SRT only, 27 were subtotally resected before SRT, and 18 underwent multiple tumor resections before SRT. We investigated the results until 2005, with a median follow-up of 45 months (range, 22-83 months). The tumor volume (TV = gross tumor volume) ranged from 0.61 to 90.20 cc (mean, 18.9 cc). Because of the risk of new visual disturbances, the dose per fraction was either 2 or 1.8 Gy for all patients, to a total dose of 50 to 60 Gy. Results: The overall survival and the progression-free survival rates for 5 years were assessed to 100% in this patient group. To date, no progression for these meningiomas have been observed. Quantitatively, tumor shrinkage of more than 20%, or more than 2 mm in diameter, was proved in 35 of the 65 cases after SRT. In 29 of the 65 patients, at least 1 of the symptoms improved. On application of the Common Toxicity Criteria (CTC), acute toxicity (Grade 3) was seen in 1 case (worsening of conjunctivitis). Another 2 patients developed late toxicity by LENT-SOMA score, 1 x Grade 1 and 1 x Grade 3 (field of vision loss). Conclusion: As a low-risk and effective treatment option for tumor control, SRT with 1.8 to 2.0 Gy per fraction can also be recommended in case of meningiomas that compress optical pathways. An

  5. Dose-Volume Histogram Analysis of Stereotactic Body Radiotherapy Treatment of Pancreatic Cancer: A Focus on Duodenal Dose Constraints.

    PubMed

    Goldsmith, Christy; Price, Patricia; Cross, Timothy; Loughlin, Sheila; Cowley, Ian; Plowman, Nicholas

    2016-04-01

    Pancreatic carcinoma is an aggressive disease and radiotherapy treatment delivery to the primary tumor is constrained by the anatomical close location of the duodenum, stomach, and small bowel. Duodenal dose tolerance for radiosurgery in 2-5 fractions has been largely unknown. The literature was surveyed for quantitative models of risk in 1-5 fractions and we analyzed our own patient population of 44 patients with unresectable pancreatic tumors who received 3 or 5 fractions of stereotactic body radiotherapy (SBRT) between March 2009 and March 2013. A logistic model was constructed in the dose-volume histogram (DVH) Evaluator software for the duodenal D50%, D30cc, D5cc, D1cc, and maximum point dose D0.035cc. Dose tolerance limits from the literature were overlaid onto the clinical duodenal data in the form of a DVH Risk Map, with risk levels of the published limits estimated from the model of clinical data. In 3 fractions, Kopek 2010 found a statistically significant difference in D1cc of patients with no common terminology criteria for adverse events (CTCAE) v3 grade 2 or higher duodenal complications (mean D1cc = 25.3Gy) as compared with patients with grade 2 or higher toxicity (mean D1cc = 37.4Gy). From the logistic model of our duodenal data in 3 fractions, D1cc = 25.3Gy had 4.7% risk of grade 3-4 hemorrhage or stricture and D1cc = 37.4Gy had 20% risk. The 10% risk level was D1cc = 31.4Gy and we were able to keep duodenum dose for all our patients later this level. PMID:27000512

  6. [Brain radiation necrosis after stereotactic radiotherapy of the resection cavity for intracranial metastases: analysis of the literature from four cases].

    PubMed

    Doré, M; Lefebvre, L; Delpon, G; Thillays, F

    2015-04-01

    Stereotactic hypofractionated radiotherapy after resection of brain metastasis is an alternative to whole brain radiotherapy. A high dose per fraction is associated with a risk of radiation necrosis. We present four cases of confirmed histological radiation necrosis. Differentiating recurrent tumour from radiation necrosis in this scenario is challenging. An enhancing area in magnetic resonance imaging (MRI) with a "cut bell pepper" appearance may suggest radiation necrosis. Advanced imaging modalities such as perfusion MR imaging and positron emission tomography can be useful. Dosimetric predictors of the occurrence of radiation necrosis after stereotactic hypofractionated radiotherapy are poorly understood and require prospective studies on larger cohorts. PMID:25573799

  7. Robust frameless stereotactic localization in extra-cranial radiotherapy

    SciTech Connect

    Riboldi, Marco; Baroni, Guido; Spadea, Maria Francesca; Bassanini, Fabio; Tagaste, Barbara; Garibaldi, Cristina; Orecchia, Roberto; Pedotti, Antonio

    2006-04-15

    In the field of extra-cranial radiotherapy, several inaccuracies can make the application of frameless stereotactic localization techniques error-prone. When optical tracking systems based on surface fiducials are used, inter- and intra-fractional uncertainties in marker three-dimensional (3D) detection may lead to inexact tumor position estimation, resulting in erroneous patient setup. This is due to the fact that external fiducials misdetection results in deformation effects that are poorly handled in a rigid-body approach. In this work, the performance of two frameless stereotactic localization algorithms for 3D tumor position reconstruction in extra-cranial radiotherapy has been specifically tested. Two strategies, unweighted versus weighted, for stereotactic tumor localization were examined by exploiting data coming from 46 patients treated for extra-cranial lesions. Measured isocenter displacements and rotations were combined to define isocentric procedures, featuring 6 degrees of freedom, for correcting patient alignment (isocentric positioning correction). The sensitivity of the algorithms to uncertainties in the 3D localization of fiducials was investigated by means of 184 numerical simulations. The performance of the implemented isocentric positioning correction was compared to conventional point-based registration. The isocentric positioning correction algorithm was tested on a clinical dataset of inter-fractional and intra-fractional setup errors, which was collected by means of an optical tracker on the same group of patients. The weighted strategy exhibited a lower sensitivity to fiducial localization errors in simulated misalignments than those of the unweighted strategy. Isocenter 3D displacements provided by the weighted strategy were consistently smaller than those featured by the unweighted strategy. The peak decrease in median and quartile values of isocenter 3D displacements were 1.4 and 2.7 mm, respectively. Concerning clinical data, the

  8. Concurrent Stereotactic Radiosurgery and Bevacizumab in Recurrent Malignant Gliomas: A Prospective Trial

    SciTech Connect

    Cabrera, Alvin R.; Cuneo, Kyle C.; Desjardins, Annick; Sampson, John H.; McSherry, Frances; Herndon, James E.; Peters, Katherine B.; Allen, Karen; Hoang, Jenny K.; Chang, Zheng; Craciunescu, Oana; Vredenburgh, James J.; Friedman, Henry S.; Kirkpatrick, John P.

    2013-08-01

    Purpose: Virtually all patients with malignant glioma (MG) eventually recur. This study evaluates the safety of concurrent stereotactic radiosurgery (SRS) and bevacizumab (BVZ), an antiangiogenic agent, in treatment of recurrent MG. Methods and Materials: Fifteen patients with recurrent MG, treated at initial diagnosis with surgery and adjuvant radiation therapy/temozolomide and then at least 1 salvage chemotherapy regimen, were enrolled in this prospective trial. Lesions <3 cm in diameter were treated in a single fraction, whereas those 3 to 5 cm in diameter received 5 5-Gy fractions. BVZ was administered immediately before SRS and 2 weeks later. Neurocognitive testing (Mini-Mental Status Exam, Trail Making Test A/B), Functional Assessment of Cancer Therapy-Brain (FACT-Br) quality-of-life assessment, physical exam, and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) were performed immediately before SRS and 1 week and 2 months following completion of SRS. The primary endpoint was central nervous system (CNS) toxicity. Secondary endpoints included survival, quality of life, microvascular properties as measured by DCE-MRI, steroid usage, and performance status. Results: One grade 3 (severe headache) and 2 grade 2 CNS toxicities were observed. No patients experienced grade 4 to 5 toxicity or intracranial hemorrhage. Neurocognition, quality of life, and Karnofsky performance status did not change significantly with treatment. DCE-MRI results suggest a significant decline in tumor perfusion and permeability 1 week after SRS and further decline by 2 months. Conclusions: Treatment of recurrent MG with concurrent SRS and BVZ was not associated with excessive toxicity in this prospective trial. A randomized trial of concurrent SRS/BVZ versus conventional salvage therapy is needed to establish the efficacy of this approach.

  9. Prognostic value of pretreatment circulating neutrophils, monocytes, and lymphocytes on outcomes in lung stereotactic body radiotherapy

    PubMed Central

    Giuliani, M.; Sampson, L.R.; Wong, O.; Gay, J.; Le, L.W.; Cho, B.C.J.; Brade, A.; Sun, A.; Bezjak, A.; Hope, A.J.

    2016-01-01

    Purpose In the present study, we determined the association of pretreatment circulating neutrophils, monocytes, and lymphocytes with clinical outcomes after lung stereotactic body radiotherapy (sbrt). Methods All patients with primary lung cancer and with a complete blood count within 3 months of lung sbrt from 2005 to 2012 were included. Overall survival (os) was calculated using the Kaplan–Meier method. Factors associated with os were investigated using univariable and multivariable Cox proportional hazards regression. Fine–Gray competing risk regression was performed to test the association of the neutrophil:lymphocyte (nlr) and monocyte:lymphocyte (mlr) ratios with two types of failure: disease-related failure and death, and death unrelated to disease. Results Of the 299 sbrt patients identified, 122 were eligible for analysis. The median and range of the nlr and mlr were 3.0 (0.3–22.0) and 0.4 (0.1–1.9) respectively. On multivariable analysis, sex (p = 0.02), T stage (p = 0.04), and nlr (p < 0.01) were associated with os. On multivariable analysis, T stage (p < 0.01) and mlr (p < 0.01) were associated with disease-related failure; mlr (p = 0.03), nlr (p < 0.01), and sbrt dose of 48 Gy in 4 fractions (p = 0.03) and 54 Gy or 60 Gy in 3 fractions (p = 0.02) were associated with disease-unrelated death. Median survival was 4.3 years in the nlr≤3 group (95% confidence interval: 3.5 to not reached) and 2.5 years in the nlr>3 group (95% confidence interval: 1.7 to 4.8; p < 0.01). Conclusions In lung sbrt patients, nlr and mlr are independently associated with os and disease-unrelated death. If validated, nlr and mlr could help to identify patients who would benefit most from sbrt. PMID:27536185

  10. 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.

  11. Salvage Stereotactic Reirradiation With or Without Cetuximab for Locally Recurrent Head-and-Neck Cancer: A Feasibility Study

    SciTech Connect

    Comet, Benedicte; Kramar, Andrew; Faivre-Pierret, Mathieu; Dewas, Sylvain; Coche-Dequeant, Bernard; Degardin, Marian; Lefebvre, Jean-Louis; Lacornerie, Thomas; Lartigau, Eric F.

    2012-09-01

    Purpose: Normal tissues tolerance limits the use of reirradiation for recurrent head-and-neck cancers (HNC). Stereotactic body radiotherapy (SBRT) could offer precise irradiation while sparing healthy tissues. Results of a feasibility study using SBRT with or without cetuximab are reported for reirradiation of recurrent primary HNC. Methods and Materials: Patients with inoperable recurrent, or new primary tumor, in a previously irradiated area were included. Reirradiation dose was 36 Gy in six fractions of 6 Gy to the 85% isodose line covering 95% of the planning target volume. Patients with squamous cell carcinoma received concomitant cetuximab. Results: Between June 2007 and January 2010, 40 patients were prospectively treated for 43 lesions. Median age was 60 and median tumor size was 29 mm. Fifteen patients received concomitant cetuximab and 1 received concomitant cisplatin. Median follow-up was 25.6 months with 34 patients evaluable for tumor response. Median overall survival was 13.6 months and response rate was 79.4% (15 complete and 12 partial responses). Grade 3 toxicity occurred in 4 patients. Conclusion: These results suggest that short SBRT with or without cetuximab is an effective salvage treatment with good response rate in this poor prognosis population with previously irradiated HNC. Treatment is feasible and, with appropriate care to limiting critical structure, acute toxicities are acceptable. A prospective multicenter Phase II trial of SRT and concomitant cetuximab in recurrent HNC squamous cell carcinoma is ongoing.

  12. Lung stereotactic radiotherapy for oligometastases: comparison of oligo-recurrence and sync-oligometastases†

    PubMed Central

    Yamashita, Hideomi; Niibe, Yuzuru; Yamamoto, Takaya; Katsui, Kuniaki; Jingu, Keiichi; Kanazawa, Susumu; Terahara, Atsuro; Nakagawa, Keiichi

    2016-01-01

    Background Oligometastases can be divided into sync-oligometastases and oligo-recurrence. The difference is whether the primary site is uncontrolled or controlled. The goal of this multicenter study was to evaluate treatment outcomes and factors affecting survival after stereotactic body radiotherapy for pulmonary oligometastases. Methods The information after stereotactic body radiotherapy from January 2004 to April 2014 was retrospectively collected. Ninety-six patients (65 males, 31 females) were enrolled. Ten cases (10%) were sync-oligometastases, 79 cases (82%) were oligo-recurrences and 7 (7%) were unclassified oligometastases with <6 months of disease-free interval. The median disease-free interval between initial therapy and stereotactic body radiotherapy was 24 months. The median calculated biological effective dose was 105.6 Gy. Results The median follow-up period was 32 months for survivors. The 3-year overall survival and relapse-free survival rates were 53% and 32%, respectively. No Grade 5 toxicity occurred. The median overall survival was 23.9 months for sync-oligometastases and 66.6 months for oligo-recurrence (P = 0.0029). On multivariate analysis, sync-oligometastases and multiple oligometastatic tumors were significant unfavorable factors for both overall survival and relapse-free survival. Conclusions In stereotactic body radiotherapy for oligometastatic lung tumors, the state of oligo-recurrence has the potential of a significant prognostic factor for survival. PMID:27162324

  13. Application of stereotactic body radiation therapy to cancer liver metastasis.

    PubMed

    Zhang, Si-Yuan; Zhu, Guang-Ying; Li, Gong; Zhang, Yi-Bao; Geng, Jian-Hao

    2016-09-01

    As an accurate external beam irradiation method, stereotactic body radiotherapy (SBRT) has been increasingly used to deliver high dose in less fractions. The liver is one of the most common organs for cancer metastasis. Recently, there have been several trials applying SBRT to cancer liver metastasis and have proved to be effective and safe with local control (LC) rates ranging from 70% to 100% within one or two years and 2-year overall survival (OS) rates ranging from 30% to 38%. Many published studies indicate that SBRT for cancer liver metastasis results in good outcomes without severe toxicities. However, the validated contribution of SBRT to an improved progression-free survival is still missing and more randomized trials should be conducted. PMID:26704306

  14. Stereotactic radiosurgery for functional disorders.

    PubMed

    Friehs, Gerhard M; Park, Michael C; Goldman, Marc A; Zerris, Vasilios A; Norén, Georg; Sampath, Prakash

    2007-01-01

    Stereotactic radiosurgery (SRS) with the Gamma Knife and linear accelerator has revolutionized neurosurgery over the past 20 years. The most common indications for radiosurgery today are tumors and arteriovenous malformations of the brain. Functional indications such as treatment of movement disorders or intractable pain only contribute a small percentage of treated patients. Although SRS is the only noninvasive form of treatment for functional disorders, it also has some limitations: neurophysiological confirmation of the target structure is not possible, and one therefore must rely exclusively on anatomical targeting. Furthermore, lesion sizes may vary, and shielding adjacent radiosensitive neural structures may be difficult or impossible. The most common indication for functional SRS is the treatment of trigeminal neuralgia. Radiosurgical treatment for epilepsy and certain psychiatric illnesses is performed in several centers as part of strict research protocols, and radiosurgical pallidotomy or medial thalamotomy is no longer recommended due to the high risk of complications. Radiosurgical ventrolateral thalamotomy for the treatment of tremor in patients with Parkinson disease or multiple sclerosis, as well as in the treatment of essential tremor, may be indicated for a select group of patients with advanced age, significant medical conditions that preclude treatment with open surgery, or patients who must receive anticoagulation therapy. A promising new application of SRS is high-dose radiosurgery delivered to the pituitary stalk. This treatment has already been successfully performed in several centers around the world to treat severe pain in patients with end-stage cancer. PMID:18081480

  15. Chest Wall Volume Receiving >30 Gy Predicts Risk of Severe Pain and/or Rib Fracture After Lung Stereotactic Body Radiotherapy

    SciTech Connect

    Dunlap, Neal E.; Cai, Jing; Biedermann, Gregory B.; Yang, Wensha; Benedict, Stanley H.; Sheng Ke; Schefter, Tracey E.; Kavanagh, Brian D.; Larner, James M.

    2010-03-01

    Purpose: To identify the dose-volume parameters that predict the risk of chest wall (CW) pain and/or rib fracture after lung stereotactic body radiotherapy. Methods and Materials: From a combined, larger multi-institution experience, 60 consecutive patients treated with three to five fractions of stereotactic body radiotherapy for primary or metastatic peripheral lung lesions were reviewed. CW pain was assessed using the Common Toxicity Criteria for pain. Peripheral lung lesions were defined as those located within 2.5 cm of the CW. A minimal point dose of 20 Gy to the CW was required. The CW volume receiving >=20, >=30, >=40, >=50, and >=60 Gy was determined and related to the risk of CW toxicity. Results: Of the 60 patients, 17 experienced Grade 3 CW pain and five rib fractures. The median interval to the onset of severe pain and/or fracture was 7.1 months. The risk of CW toxicity was fitted to the median effective concentration dose-response model. The CW volume receiving 30 Gy best predicted the risk of severe CW pain and/or rib fracture (R{sup 2} = 0.9552). A volume threshold of 30 cm{sup 3} was observed before severe pain and/or rib fracture was reported. A 30% risk of developing severe CW toxicity correlated with a CW volume of 35 cm{sup 3} receiving 30 Gy. Conclusion: The development of CW toxicity is clinically relevant, and the CW should be considered an organ at risk in treatment planning. The CW volume receiving 30 Gy in three to five fractions should be limited to <30 cm{sup 3}, if possible, to reduce the risk of toxicity without compromising tumor coverage.

  16. Toxicity and outcomes of thoracic re-irradiation using stereotactic body radiation therapy (SBRT)

    PubMed Central

    2013-01-01

    Background Patients treated for a thoracic malignancy carry a significant risk of developing other lung lesions. Locoregional control of intrathoracic recurrences is challenging due to the impact of prior therapies on normal tissues. We examined the safety and efficacy of thoracic re-irradiation using high-precision image-guided stereotactic body radiation therapy (SBRT). Methods Records of 39 patients with prior intra-thoracic conventionally fractionated radiation therapy (RT) who underwent SBRT for a subsequent primary, recurrent or metastatic lung tumor from 11/2004 to 7/2011 were retrospectively reviewed. Results Median dose of prior RT was 61 Gy (range 30–80 Gy). Median biologically effective prescription dose (α/β = 10) (BED10) of SBRT was 70.4 Gy (range 42.6-180 Gy). With a median followup of 12.6 months among survivors, 1- and 2-year actuarial local progression-free survival (LPFS) were 77% and 64%, respectively. Median recurrence-free (RFS) and overall survival (OS) were 13.8 and 22.0 months, respectively. Patients without overlap of high-dose regions of the primary and re-irradiation plans were more likely to receive a BED10 ≥100 Gy, which was associated with higher LPFS (hazard ratio, [HR] = 0.18, p = 0.04), RFS ([HR] = 0.31, p = 0.038) and OS ([HR] = 0.25, p = 0.014). Grade 2 and 3 pulmonary toxicity was observed in 18% and 5% of patients, respectively. Other grade 2–4 toxicities included chest wall pain in 18%, fatigue in 15% and skin toxicity in 5%. No grade 5 events occurred. Conclusions SBRT can be safely and successfully administered to patients with prior thoracic RT. Dose reduction for cases with direct overlap of successive radiation fields results in acceptable re-treatment toxicity profile. PMID:23617949

  17. Stereotactic body radiotherapy for lung metastases as oligo-recurrence: a single institutional study

    PubMed Central

    Aoki, Masahiko; Hatayama, Yoshiomi; Kawaguchi, Hideo; Hirose, Katsumi; Sato, Mariko; Akimoto, Hiroyoshi; Miura, Hiroyuki; Ono, Shuichi; Takai, Yoshihiro

    2016-01-01

    The purpose of this study was to investigate clinical outcomes following stereotactic body radiotherapy (SBRT) for lung metastases as oligo-recurrence. From May 2003 to June 2014, records for 66 patients with 76 oligo-recurrences in the lungs treated with SBRT were retrospectively reviewed. Oligo-recurrence primary sites and patient numbers were as follows: lungs, 31; colorectal, 13; head and neck, 10; esophagus, 3; uterus, 3; and others, 6. The median SBRT dose was 50 Gy (range, 45–60 Gy) administered in a median of 5 (range, 5–9) fractions. All patients received SBRT, with no acute toxicity. Surviving patients had a median follow-up time of 36.5 months. The 3-year rates of local control, overall survival and disease-free survival were 90.6%, 76.0% and 53.7%, respectively. Longer disease-free interval from initial treatment to SBRT, and non-colorectal cancer were both associated with favorable outcomes. Disease progression after SBRT occurred in 31 patients, most with distant metastases (n = 24) [among whom, 87.5% (n = 21) had new lung metastases]. Among these 21 patients, 12 were judged as having a second oligo-recurrence. Additional SBRT was performed for these 12 patients, and all 12 tumors were controlled without disease progression. Three patients (4.5%) developed Grade 2 radiation pneumonitis. No other late adverse events of Grade ≥2 were identified. Thus, SBRT for oligo-recurrence achieved acceptable tumor control, with additional SBRT also effective for selected patients with a second oligo-recurrence after primary SBRT. PMID:26494115

  18. Adaptation of telecobalt unit for stereotactic irradiation

    SciTech Connect

    Singh, I. Rabi Raja . E-mail: rabiraja@cmcvellore.ac.in; Ravindran, B. Paul; Ayyangar, K.M.

    2007-04-01

    We investigated the feasibility of using an isocentric telecobalt unit for advanced treatment techniques, such as stereotactic radiotherapy. To adapt the telecobalt unit (Th780 C) for stereotactic irradiation, collimator inserts of various sizes, collimator mount, and a couch mount suitable for the telecobalt unit were developed, and the characteristics of the narrow beams of Cobalt-60 ({sup 60}Co) were studied. Comparative study was carried out between the stereotactic radiotherapy plans of 6 MV and {sup 60}Co beams using a 3-dimensional (3D) treatment planning system. The beam penumbra of {sup 60}Co beams was found to be larger than those of 6 MV beams. The dose-volume histograms (DVH) obtained from the {sup 60}Co beam plan were comparable to those obtained from the 6 MV plan. The DVH of nontarget tissue obtained from the plans of the 2 beams were found to be in good agreement to each other. The difference in equivalent fall-off distance (EFOD) for all 3 cases was found insignificant; hence, it can be concluded that the fall-off dose in the dose distribution of the {sup 60}Co stereotactic plan is as good as that of the 6 MV stereotactic plan. In all 3 cases for which the treatment plans were compared between {sup 60}Co and 6 MV beams, it was observed that the fall-off doses outside the target were similar; therefore, considering {sup 60}Co with 5-mm margin is a cost effective alternative for the linac-based stereotactic radiotherapy.

  19. A discrete fractional random transform

    NASA Astrophysics Data System (ADS)

    Liu, Zhengjun; Zhao, Haifa; Liu, Shutian

    2005-11-01

    We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

  20. Imaging of Radiation Dose for Stereotactic Radiosurgery.

    PubMed

    Guan, Timothy Y; Almond, Peter R; Park, Hwan C; Lindberg, Robert D; Shields, Christopher B

    2015-01-01

    The distributions of radiation dose for stereotactic radiosurgery, using a modified linear accelerator (Philips SL-25 and SRS-200), have been studied by using three different dosimeters: (1) ferrous-agarose-xylenol orange (FAX) gels, (2) TLD, and (3) thick-emulsion GafChromic dye film. These dosimeters were loaded into a small volume of defect in a phantom head. A regular linac stereotactic radiosurgery treatment was then given to the phantom head for each type of dosimeter. The measured radiation dose and its distributions were found to be in good agreement with those calculated by the treatment planning computer. PMID:27421869

  1. Integral Whole Brain Dose from Stereotactic Radiosurgery of 47 Metastatic Lesions: A Dosimetric Case Study

    PubMed Central

    Chen, Joseph C; Miller, Michael J; Lodin, Kenneth; Girvigian, Michael R

    2015-01-01

    This report describes the case of a 15-year-old male diagnosed with primary ALK-positive adenocarcinoma of the lung metastatic to the brain. He was treated with surgical resection for a single lesion followed by whole brain radiotherapy and subsequently underwent 10 courses of stereotactic radiosurgery for 47 lesions delivered over a four-year period. Currently, all metastatic lesions in the brain are completely resolved or locally controlled. PMID:26858917

  2. Stereotactic Ablative Radiotherapy for the Treatment of Clinically Localized Renal Cell Carcinoma

    PubMed Central

    Campbell, Scott P.; Song, Daniel Y.; Pierorazio, Phillip M.; Allaf, Mohamad E.; Gorin, Michael A.

    2015-01-01

    Thermal ablation is currently the most studied treatment option for medically inoperable patients with clinically localized renal cell carcinoma (RCC). Recent evidence suggests that stereotactic ablative radiotherapy (SABR) may offer an effective noninvasive alternative for these patients. In this review, we explore the current literature on SABR for the primary treatment of RCC and make recommendations for future studies so that an accurate comparison between SABR and other ablative therapies may be conducted. PMID:26640488

  3. High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station.

    PubMed

    Accardo, L; Aguilar, M; Aisa, D; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Carosi, G; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cerreta, D; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Cindolo, F; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Du, W J; Duranti, M; D'Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Haas, D; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Henning, R; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Levi, G; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lolli, M; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Massera, F; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Monreal, B; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pauluzzi, M; Pedreschi, E; Pensotti, S; Pereira, R; Pilastrini, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rossi, L; Rozhkov, A; Rozza, D; Rybka, G; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Vitale, V; Volpini, G; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Wu, K Y; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhou, F; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

    2014-09-19

    A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron fraction no longer exhibits an increase with energy. PMID:25279616

  4. Stereotactic Body Radiosurgery for Spinal Metastatic Disease: An Evidence-Based Review

    PubMed Central

    Hall, William A.; Stapleford, Liza J.; Hadjipanayis, Costas G.; Curran, Walter J.; Crocker, Ian; Shu, Hui-Kuo G.

    2011-01-01

    Spinal metastasis is a problem that afflicts many cancer patients. Traditionally, conventional fractionated radiation therapy and/or surgery have been the most common approaches for managing such patients. Through technical advances in radiotherapy, high dose radiation with extremely steep drop off can now be delivered to a limited target volume along the spine under image-guidance with very high precision. This procedure, known as stereotactic body radiosurgery, provides a technique to rapidly treat selected spinal metastasis patients with single- or limited-fraction treatments that have similar to superior efficacies compared with more established approaches. This review describes current treatment systems in use to deliver stereotactic body radiosurgery as well as results of some of the larger case series from a number of institutions that report outcomes of patients treated for spinal metastatic disease. These series include nearly 1400 patients and report a cumulative local control rate of 90% with myelopathy risk that is significantly less than 1%. Based on this comprehensive review of the literature, we believe that stereotactic body radiosurgery is an established treatment modality for patients with spinal metastatic disease that is both safe and highly effective. PMID:22312536

  5. Modelling the Gross Primary Productivity of West Africa with the Regional Biomass Model RBM+, using optimized 250 m MODIS FPAR and fractional vegetation cover information

    NASA Astrophysics Data System (ADS)

    Machwitz, Miriam; Gessner, Ursula; Conrad, Christopher; Falk, Ulrike; Richters, Jochen; Dech, Stefan

    2015-12-01

    Global warming associated with climate change is one of the greatest challenges of today's world. Increasing emissions of the greenhouse gas CO2 are considered as a major contributing factor to global warming. One regulating factor of CO2 exchange between atmosphere and land surface is vegetation. Measurements of land cover changes in combination with modelling the Gross Primary Productivity (GPP) can contribute to determine important sources and sinks of CO2. The aim of this study is to accurately model the GPP for a region in West Africa with a spatial resolution of 250 m, and the differentiation of GPP based on woody and herbaceous vegetation. For this purpose, the Regional Biomass Model (RBM) was applied, which is based on a Light Use Efficiency (LUE) approach. The focus was on the spatial enhancement of the RBM from the original 1000-250 m spatial resolution (RBM+). The adaptation to the 250 m scale included the modification of two main input parameters: (1) the fraction of absorbed Photosynthetically Active Radiation (FPAR) based on the 1000 m MODIS MOD15A2 FPAR product which was downscaled to 250 m using MODIS NDVI time series; (2) the fractional cover of woody and herbaceous vegetation, which was improved by using a multi-scale approach. For validation and regional adjustments of GPP and the input parameters, in situ data from a climate station and eddy covariance measurements were integrated. The results of this approach show that the input parameters could be improved significantly: downscaling considerably reduces data gaps of the original FPAR product and the improved dataset differed less than 5.0% from the original data for cloud free regions. The RMSE of the fractional vegetation cover varied between 5.1 and 12.7%. Modelled GPP showed a slight overestimation in comparison to eddy covariance measurements. The in situ data was exceeded by 8.8% for 2005 and by 2.0% for 2006. The model results were converted to NPP and also agreed well with previous NPP

  6. Evaluation of efficacy and safety of robotic stereotactic body radiosurgery and hypofractionated stereotactic radiotherapy for vertebral metastases

    PubMed Central

    Blamek, Sławomir; Roch-Zniszczoł, Agata; Stąpór-Fudzińska, Małgorzata; Miszczyk, Leszek

    2015-01-01

    Aim of the study The purpose of this study was to evaluate the efficacy and safety of applying CyberKnife (CK) radiosurgery in patients with spinal metastases. Material and methods Twenty-eight patients with vertebral metastases treated using the CK system were included in the study. Eleven patients suffered from pain, and in 1 case neurological symptoms were observed. The remaining patients were free from clinical symptoms of metastatic disease. The doses applied ranged between 8 and 40 Gy delivered in 4 fractions of 8–15 Gy. Results In the first follow-up evaluation (mean 4.5 months after the treatment), pain was stable in 5 of 8 evaluable cases and in 3 regression occurred. The last follow-up examination (mean 11 months after stereotactic radiosurgery) revealed stable ailments in 3 of 6 evaluable cases, improvement in 3 and new complaints in another 4 patients. In 17 patients imaging studies were conducted after a mean time of 11 months after CK treatment. Stabilization was confirmed in 11, regression in 4 and progression in 2 cases. Median overall survival was 20.6 months. Median progression-free survival was 12.6 months. No side effects attributable to the treatment were observed, but during follow-up transient or permanent deterioration in neurological status as a consequence of disease progression was diagnosed in 4 patients. Delivery time of a single fraction ranged between 0.5 and 1.5 hours. Conclusions Robotic stereotactic radiosurgery as part of multimodality therapy for metastatic spinal tumours is safe and effective. Because of long irradiation times, this kind of treatment is not suitable for patients in poor general condition. PMID:26557782

  7. Fatal complications after stereotactic body radiation therapy for central lung tumors abutting the proximal bronchial tree

    PubMed Central

    Haseltine, Justin M.; Rimner, Andreas; Gelblum, Daphna Y.; Modh, Ankit; Rosenzweig, Kenneth E.; Jackson, Andrew; Yorke, Ellen D.; Wu, Abraham J.

    2016-01-01

    Purpose Stereotactic body radiation therapy (SBRT) is associated with excess toxicity following treatment of central lung tumors. Risk-adapted fractionation appears to have mitigated this risk, but it remains unclear whether SBRT is safe for all tumors within the central lung zone, especially those abutting the proximal bronchial tree (PBT). We investigated the dependence of toxicity on tumor proximity to PBT and whether tumors abutting the PBT had greater toxicity than other central lung tumors after SBRT. Materials and methods A total of 108 patients receiving SBRT for central lung tumors were reviewed. Patients were classified based on closest distance from tumor to PBT. Primary endpoint was SBRT-related death. Secondary endpoints were overall survival, local control, and grade 3+ pulmonary adverse events. We compared tumors abutting the PBT to nonabutting and those ≤1 cm and >1 cm from PBT. Results Median follow-up was 22.7 months. Median distance from tumor to PBT was 1.78 cm. Eighty-eight tumors were primary lung and 20 were recurrent or metastatic; 23% of tumors were adenocarcinoma and 71% squamous cell. Median age was 77.5 years. Median dose was 4500 cGy in 5 fractions prescribed to the 100% isodose line. Eighteen patients had tumors abutting the PBT, 4 of whom experienced SBRT-related death. No other patients experienced death attributed to SBRT. Risk of SBRT-related death was significantly higher for tumors abutting the PBT compared with nonabutting tumors (P < .001). Two patients with SBRT-related death received anti-vascular endothelial growth factor therapy and experienced pulmonary hemorrhage. Patients with tumors ≤1 cm from PBT had significantly more grade 3+ events than those with tumors >1cm from PBT (P = .014). Conclusions Even with risk-adapted fractionation, tumors abutting PBT are associated with a significant and differential risk of SBRT-related toxicity and death. SBRT should be used with particular caution in central-abutting tumors

  8. Image-Guided Stereotactic Spine Radiosurgery on a Conventional Linear Accelerator

    SciTech Connect

    Wang Jiazhu Rice, Roger; Mundt, Arno; Sandhu, Ajay; Murphy, Kevin

    2010-04-01

    Stereotactic radiosurgery for spinal metastasis consists of a high radiation dose delivered to the tumor in 1 to 5 fractions. Due to the high radiation dose in a single or fewer treatments, the precision of tumor localization and dose delivery is of great concern. Many groups have published their experiences of spinal radiosurgery with the use of CyberKnife System (Accuray Inc.). In this study, we report in detail our approach to stereotactic spine radiosurgery (SSRS) using a conventional linear accelerator (Varian Trilogy), utilizing the features of kilovolt on-board imaging (kV-OBI) and cone beam computed tomography (CBCT) for image guidance. We present our experience in various aspects of the SSRS procedure, including patient simulation and immobilization, intensity-modulated radiation treatment (IMRT) planning and beam selection, portal dosimetry for patient planning quality assurance (QA), and the use of image guidance in tumor localization prior to and during treatment delivery.

  9. Dose profile measurements during respiratory-gated lung stereotactic radiotherapy: A phantom study

    NASA Astrophysics Data System (ADS)

    Jong, W. L.; Wong, J. H. D.; Ng, K. H.; Ung, N. M.

    2016-03-01

    During stereotactic body radiotherapy, high radiation dose (∼60 Gy) is delivered to the tumour in small fractionation regime. In this study, the dosimetric characteristics were studied using radiochromic film during respiratory-gated and non-gated lung stereotactic body radiotherapy (SBRT). Specifically, the effect of respiratory cycle and amplitude, as well as gating window on the dosimetry were studied. In this study, the dose profiles along the irradiated area were measured. The dose profiles for respiratory-gated radiation delivery with different respiratory or tumour motion amplitudes, gating windows and respiratory time per cycle were in agreement with static radiation delivery. The respiratory gating system was able to deliver the radiation dose accurately (±1.05 mm) in the longitudinal direction. Although the treatment time for respiratory-gated SBRT was prolonged, this approach can potentially reduce the margin for internal tumour volume without compromising the tumour coverage. In addition, the normal tissue sparing effect can be improved.

  10. Quality Assurance of Immobilization and Target Localization Systems for Frameless Stereotactic Cranial and Extracranial Hypofractionated Radiotherapy

    SciTech Connect

    Solberg, Timothy D. Medin, Paul M.; Mullins, John; Li Sicong

    2008-05-01

    The success of stereotactic radiosurgery has stimulated significant interest in the application of such an approach for the treatment of extracranial tumors. The potential benefits of reduced healthcare costs and improved patient outcomes that could be realized in a high-precision, hypofractionated treatment paradigm are numerous. Image-guidance technologies are eliminating the historic requirement for rigid head fixation and will also accelerate the clinical implementation of the approach in extracranial sites. An essential prerequisite of 'frameless' stereotactic systems is that they provide localization accuracy consistent with the safe delivery of a therapeutic radiation dose given in one or few fractions. In this report, we reviewed the technologies for frameless localization of cranial and extracranial targets with emphasis on the quality assurance aspects.

  11. The use of spine stereotactic radiosurgery for oligometastatic disease.

    PubMed

    Ho, Jennifer C; Tang, Chad; Deegan, Brian J; Allen, Pamela K; Jonasch, Eric; Amini, Behrang; Wang, Xin A; Li, Jing; Tatsui, Claudio E; Rhines, Laurence D; Brown, Paul D; Ghia, Amol J

    2016-08-01

    OBJECTIVE The authors investigated the outcomes following spine stereotactic radiosurgery (SSRS) for patients with oligometastatic disease of the spine. METHODS The study was a secondary analysis of 38 of 209 patients enrolled in 2 separate institutional Phase I/II prospective protocols and treated with SSRS between 2002 and 2011. Of these 38 patients, 33 (87%) were treated for a solitary spine metastasis, with no other history of metastatic disease. SSRS was prescribed to 24 Gy in 1 fraction (8%), 18 Gy in 1 fraction (18%), 16 Gy in 1 fraction (11%), 27 Gy in 3 fractions (53%), 30 Gy in 5 fractions (8%), or 20 Gy in 5 fractions (3%). Seventeen patients (45%) received prior conventional external beam radiation therapy. RESULTS The median overall survival (OS) was 75.7 months, and the 2- and 5-year OS rates were 84% and 60%, respectively. In multivariate analysis, patients who had prior spine surgery and a better Karnofsky Performance Scale score had an improved OS (HR 0.16, 95% CI 0.05-0.52, p < 0.01, and HR 0.33, 95% CI 0.13%-0.84%, p = 0.02, respectively), and those who had undergone prior radiation therapy had a worse OS (HR 3.6, 95% CI 1.2%-10%, p = 0.02). The 1-, 2-, and 5-year local progression-free survival rates were 85%, 82%, and 78%, respectively. The median time to systemic therapy modification was 41 months. Two patients (5%) experienced late Grade 3-4 toxicity. CONCLUSIONS Patients with oligometastatic disease of the spine treated with SSRS can experience long-term survival and a long time before needing a modification in systemic therapy. In addition, SSRS leads to excellent local control and minimal late toxicity. PMID:27035507

  12. Imaging for Stereotactic Spine Radiotherapy: Clinical Considerations

    SciTech Connect

    Dahele, Max; Zindler, Jaap D.; Sanchez, Esther; Verbakel, Wilko F.; Kuijer, Joost P.A.; Slotman, Ben J.; Senan, Suresh

    2011-10-01

    There is growing interest in the use of stereotactic body radiation therapy (SBRT) for spinal metastases. With the need for accurate target definition and conformal avoidance of critical normal structures, high-quality multimodal imaging has emerged as a key component at each stage of the treatment process. Multidisciplinary collaboration is necessary to optimize imaging protocols and implement imaging advances into routine patient care.

  13. Effective Rat Lung Tumor Model for Stereotactic Body Radiation Therapy.

    PubMed

    Zhang, Zhang; Wodzak, Michelle; Belzile, Olivier; Zhou, Heling; Sishc, Brock; Yan, Hao; Stojadinovic, Strahinja; Mason, Ralph P; Brekken, Rolf A; Chopra, Rajiv; Story, Michael D; Timmerman, Robert; Saha, Debabrata

    2016-06-01

    Stereotactic body radiation therapy (SBRT) has found an important role in the treatment of patients with non-small cell lung cancer, demonstrating improvements in dose distribution and even tumor cure rates, particularly for early-stage disease. Despite its emerging clinical efficacy, SBRT has primarily evolved due to advances in medical imaging and more accurate dose delivery, leaving a void in knowledge of the fundamental biological mechanisms underlying its activity. Thus, there is a critical need for the development of orthotropic animal models to further probe the biology associated with high-dose-per-fraction treatment typical of SBRT. We report here on an improved surgically based methodology for generating solitary intrapulmonary nodule tumors, which can be treated with simulated SBRT using the X-RAD 225Cx small animal irradiator and Small Animal RadioTherapy (SmART) Plan treatment system. Over 90% of rats developed solitary tumors in the right lung. Furthermore, the tumor response to radiation was monitored noninvasively via bioluminescence imaging (BLI), and complete ablation of tumor growth was achieved with 36 Gy (3 fractions of 12 Gy each). We report a reproducible, orthotopic, clinically relevant lung tumor model, which better mimics patient treatment regimens. This system can be utilized to further explore the underlying biological mechanisms relevant to SBRT and high-dose-per-fraction radiation exposure and to provide a useful model to explore the efficacy of radiation modifiers in the treatment of non-small cell lung cancer. PMID:27223828

  14. Observation of a Dose-Control Relationship for Lung and Liver Tumors After Stereotactic Body Radiation Therapy

    SciTech Connect

    McCammon, Robert Schefter, Tracey E.; Gaspar, Laurie E.; Zaemisch, Rebekah; Gravdahl, Daniel; Kavanagh, Brian

    2009-01-01

    Purpose: To determine prognostic factors for local control of primary or metastatic tumors within the lung or liver treated with stereotactic body radiation therapy (SBRT) within a single institution. Methods and Materials: The records of 141 consecutive patients with 246 lesions treated with three-fraction SBRT from Oct 1999 through Aug 2005 were reviewed. Local control was assessed radiographically. Univariate and multivariate analyses were performed to evaluate the influence of the following factors on local control: total dose, expressed as either nominal prescription dose or equivalent uniform dose (EUD); gross tumor volume; primary site; treatment site (lung vs. other); histologic characteristics (adenocarcinoma vs. other); gender; age; and primary vs. metastatic tumor. Results: On univariate analysis, increased dose (either nominal or EUD) and smaller gross tumor volume were significant predictors of higher local control. Lesions treated to a nominal dose of 54 Gy or greater had a 3-year actuarial local control rate of 89.3% compared with 59.0% and 8.1% for those treated to 36-53.9 Gy and less than 36 Gy. On multivariate analysis, only increased nominal dose and EUD retained statistical significance. Treatment was well tolerated; 5.7% of patients experienced Grade 3 or higher toxicity. Conclusions: This large single-institution series suggests a dose-control relationship within the range of SBRT doses applied. Excellent local control rates are achieved with a nominal dose of 54 Gy or greater, corresponding to an EUD greater than 65.3 Gy. These results support the use of aggressive SBRT regimens when durable tumor control is the primary objective.

  15. Regional Normal Lung Tissue Density Changes in Patients Treated With Stereotactic Body Radiation Therapy for Lung Tumors

    SciTech Connect

    Diot, Quentin; Kavanagh, Brian; Schefter, Tracey; Gaspar, Laurie; Stuhr, Kelly; Miften, Moyed

    2012-11-15

    Purpose: To describe regional lung tissue density changes in normal lung tissue of patients with primary and metastatic lung tumors who received stereotactic body radiation therapy (SBRT). Methods and Materials: A total of 179 post-SBRT follow-up computed tomography (CT) scans of 62 patients who received SBRT between 2003 and 2009 were studied. Median prescription dose was 54 Gy (range, 30-60 Gy) in 3 to 5 fractions. SBRT-induced lung density changes on post-SBRT follow-up CT were evaluated at approximately 3, 6, 12, 18, 24, and 30 months after treatment. Dose-response curves (DRC) were generated for SBRT-induced lung damage by averaging CT number (HU) changes for regions of the lungs receiving the same dose at 5-Gy intervals. Results: For all follow-up interval periods, CT numbers linearly increased with dose until 35 Gy and were constant thereafter. For 3, 18, 24, and 30 months, the rate of relative electron density increase with dose was approximately 0.24% per Gy. At 6 months, the rate was also similar below 20 Gy but then rose to 0.6% per Gy above this threshold. After 6 months, DRCs were mostly time-independent. When split between patients treated with 3 fractions of 12 to 20 Gy (median, 20 Gy; average tumor volume, 12 {+-} 16 cm{sup 3}) and with >3 fractions of 6 to 12.5 Gy (median, 9 Gy; average tumor volume, 30 {+-} 40 cm{sup 3}), DRCs differed significantly. In both cases, CT changes at 3, 18, 24, and 30 months were identical to those of the population DRC; however, patients who received >3 fractions showed 6-month CT changes that were more than twice those for the group that received 3 fractions. Conclusions: This analysis of SBRT-induced normal lung density changes indicates that lung normal tissue has more pronounced self-limited acute effects than late effects. Differences in acute CT changes following treatments in 3 fractions were considerably less than for treatments in >3 fractions.

  16. Stereotactic Radiotherapy for Intracranial Nonacoustic Schwannomas Including Facial Nerve Schwannoma

    SciTech Connect

    Nishioka, Kentaro; Abo, Daisuke; Aoyama, Hidefumi; Furuta, Yasushi; Onimaru, Rikiya; Onodera, Shunsuke; Sawamura, Yutaka; Ishikawa, Masayori; Fukuda, Satoshi; Shirato, Hiroki

    2009-12-01

    Purpose: Although the effectiveness of stereotactic radiosurgery for nonacoustic schwannomas is currently being assessed, there have been few studies on the efficacy of stereotactic radiotherapy (SRT) for these tumors. We investigated the long-term outcome of SRT for nonacoustic intracranial nerve schwannomas. Methods and Materials: Seventeen patients were treated between July 1994 and December 2006. Of these patients, 7 had schwannomas located in the jugular foramen, 5 in the trigeminal nerve, 4 in the facial nerve, and 1 in the oculomotor nerve. Radiotherapy was used as an initial treatment without surgery in 10 patients (59%) and after initial subtotal resection in the remaining patients. The tumor volume ranged from 0.3 to 31.3 mL (mean, 8.2 mL). The treatment dose was 40 to 54 Gy in 20 to 26 fractions. The median follow-up period was 59.5 months (range, 7.4-122.6 months). Local control was defined as stable or decreased tumor size on follow-up magnetic resonance imaging. Results: Tumor size was decreased in 3 patients, stable in 13, and increased in 1 after SRT. Regarding neurologic symptoms, 8 patients (47%) had improvement and 9 patients were unchanged. One patient had an increase in tumor size and received microsurgical resection at 32 months after irradiation. No patient had worsening of pre-existing neurologic symptoms or development of new cranial nerve deficits at the last follow-up. Conclusions: SRT is an effective alternative to surgical resection for patients with nonacoustic intracranial nerve schwannomas with respect to not only long-term local tumor control but also neuro-functional preservation.

  17. Comparing the clinical outcomes in stereotactic body radiotherapy for lung tumors between Ray-Tracing and Monte-Carlo algorithms

    PubMed Central

    Song, Jin Ho; Kang, Ki Mun; Choi, Hoon-Sik; Jeong, Hojin; Ha, In Bong; Lee, Jong Deog; Kim, Ho Cheol; Jeong, Yi Yeong; Cho, Yu Ji; Lee, Seung Jun; Kim, Sung Hwan; Jang, In-Seok; Jeong, Bae Kwon

    2016-01-01

    Purpose The purpose of this study was to compare the clinical outcomes between the groups using Ray-Tracing (RAT) and Monte-Carlo (MC) calculation algorithms for stereotactic body radiotherapy (SBRT) of lung tumors. Materials and Methods Thirty-five patients received SBRT with CyberKnife for 47 primary or metastatic lung tumors. RAT was used for 22 targets in 12 patients, and MC for 25 targets in 23 patients. Total dose of 48 to 60 Gy was prescribed in 3 to 5 fractions on median 80% isodose line. The response rate, local control rate, and toxicities were compared between RAT and MC groups. Results The response rate was lower in the RAT group (77.3%) compared to the MC group (100%) (p = 0.008). The response rates showed an association with the mean dose to the gross tumor volume, which the doses were re-calculated with MC algorithm in both groups. However, the local control rate and toxicities did not differ between the groups. Conclusions The clinical outcome and toxicity of lung SBRT between the RAT and MC groups were similar except for the response rate when the same apparent doses were prescribed. The lower response rate in the RAT group, however, did not compromise the local control rates. As such, reducing the prescription dose for MC algorithm may be performed but done with caution. PMID:26544622

  18. Stereotactic Ablative Radiation Therapy as First Local Therapy for Lung Oligometastases From Colorectal Cancer: A Single-Institution Cohort Study

    SciTech Connect

    Filippi, Andrea Riccardo; Badellino, Serena; Ceccarelli, Manuela; Guarneri, Alessia; Franco, Pierfrancesco; Monagheddu, Chiara; Spadi, Rosella; Ragona, Riccardo; Racca, Patrizia; Ricardi, Umberto

    2015-03-01

    Purpose: To estimate stereotactic ablative radiation therapy (SABR) efficacy and its potential role as an alternative to surgery for the treatment of lung metastases from colorectal cancer. Methods and Materials: Forty consecutive patients who received SABR as first local therapy at the time of lung progression were included, from 2004 to 2014. The primary study endpoint was overall survival. Secondary endpoints were progression-free survival and safety. Results: A single nodule was treated in 26 patients (65%), 2 nodules in 10 patients (25%), 3 in 3 patients (7.5%), and 4 in 1 patient (2.5%), for a total of 59 lesions. The median delivered biological effective dose was 96 Gy, in 1 to 8 daily fractions. Median follow-up time was 20 months (range, 3-72 months). Overall survival rates at 1, 2, and 5 years were, respectively, 84%, 73%, and 39%, with 14 patients (35%) dead. Median overall survival was 46 months. Progression occurred in 25 patients (62.5%), at a median interval of 8 months; failure at SABR site was observed in 3 patients (7.5%). Progression-free survival rates were 49% and 27% at 1 and 2 years, respectively. Discussion: The results of this retrospective exploratory analysis suggest safety and efficacy of SABR in patients affected with colorectal cancer lung oligometastases and urge inclusion of SABR in prospective clinical trials.

  19. Neovascular Glaucoma After Stereotactic Radiotherapy for Juxtapapillary Choroidal Melanoma: Histopathologic and Dosimetric Findings

    SciTech Connect

    Fernandes, Bruno F.; Weisbrod, Daniel; Yuecel, Yeni H.; Follwell, Matthew; Krema, Hatem; Heydarian, Mostafa; Xu Wei; Payne, David; McGowan, Hugh; Simpson, Ernest R.; Laperriere, Normand; Sahgal, Arjun

    2011-06-01

    Purpose: Enucleation after stereotactic radiotherapy (SRT) for juxtapapillary choroidal melanoma may be required because of tumor progression (TP) or the development of intractable radiation-induced neovascular glaucoma (NVG). We compare pathologic changes and dosimetric findings in those eyes enucleated secondary to NVG as opposed to TP to better understand potential mechanisms. Methods and Materials: Patients with juxtapapillary choroidal melanoma treated with SRT (70 Gy in 5 fractions, alternate days over a total of 10 days) at the Princess Margaret Hospital, Toronto, Ontario, Canada, who underwent enucleation between 1998 and 2006 were selected. We correlated dosimetric data based on the patient's original SRT treatment plan with histopathologic findings in the retina, optic nerve head, and anterior chamber. A dedicated ocular pathologist reviewed each case in a blinded fashion. Results: Ten eyes in ten patients were enucleated after SRT. Six were enucleated secondary to NVG and four secondary to because of TP. Aggressive tumor features such as invasion of the sclera and epithelioid cell type were observed predominantly in the TP group. Retinal damage was more predominant in the NVG group, as were findings of radiation-related retinal vascular changes of fibrinoid necrosis and hyalinization. No conclusive radiation-related effects were found in the anterior chamber. The maximum point dose and dose to 0.1 cc were lower for the anterior chamber as compared with the dose to the tumor, retina, and optic nerve head. The mean 0.1-cc doses to the retina were 69.4 Gy and 73.5 Gy and to the anterior chamber were 4.9 Gy and 17.3 Gy for the NVG group and tumor progression group, respectively. Conclusions: Our findings suggest that NVG is due to radiation damage to the posterior chamber of the eye rather than primary radiation damage to the anterior segment.

  20. Stereotactic body radiation therapy for liver tumours using flattening filter free beam: dosimetric and technical considerations

    PubMed Central

    2012-01-01

    Purpose To report the initial institute experience in terms of dosimetric and technical aspects in stereotactic body radiation therapy (SBRT) delivered using flattening filter free (FFF) beam in patients with liver lesions. Methods and Materials From October 2010 to September 2011, 55 consecutive patients with 73 primary or metastatic hepatic lesions were treated with SBRT on TrueBeam using FFF beam and RapidArc technique. Clinical target volume (CTV) was defined on multi-phase CT scans, PET/CT, MRI, and 4D-CT. Dose prescription was 75 Gy in 3 fractions to planning target volume (PTV). Constraints for organs at risk were: 700 cc of liver free from the 15 Gy isodose, Dmax < 21 Gy for stomach and duodenum, Dmax < 30 Gy for heart, D0.1 cc < 18 Gy for spinal cord, V15 Gy < 35% for kidneys. The dose was downscaled in cases of not full achievement of dose constraints. Daily cone beam CT (CBCT) was performed. Results Forty-three patients with a single lesion, nine with two lesions and three with three lesions were treated with this protocol. Target and organs at risk objectives were met for all patients. Mean delivery time was 2.8 ± 1.0 min. Pre-treatment plan verification resulted in a Gamma Agreement Index of 98.6 ± 0.8%. Mean on-line co-registration shift of the daily CBCT to the simulation CT were: -0.08, 0.05 and -0.02 cm with standard deviations of 0.33, 0.39 and 0.55 cm in, vertical, longitudinal and lateral directions respectively. Conclusions SBRT for liver targets delivered by means of FFF resulted to be feasible with short beam on time. PMID:22296849

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

    PubMed

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

    2010-01-01

    Medial middle fossa meningiomas are challenging for neurosurgical treatment. Invasion of cranial nerves and vessels leads to high risk of complications after removal of such meningiomas. Currently methods of conformal stereotactic radiation treatment are applied wider and wider for the discussed lesions. During a 3.5-year period 80 patients with medial middle fossa meningiomas were treated in Burdenko Moscow Neurosurgical Institute using linear accelerator "Novalis". In 31 case radiation treatment was preceded by surgical resection. In majority of patients symptoms included cranial nerve dysfunction: oculomotor disturbances in 62.5%, trigeminal impairment--in 37.5%, visual deficit--in 43.8%, facial nerve palsy--in 1.25%. 74 patients underwent radiotherapy with classical fractioning, 2--in hypofractionated mode and 4 received radiosurgery. In cases of classical fractioning mean marginal dose reached 46.3 Gy during 28-33 fractions, in hypofractioning (7 fractions)--31.5 Gy, in radiosurgery--16.25 Gy. Mean follow-up period was 18.4 months (6-42 months). Control of tumor growth was achieved in 97.5% of cases (78 patients): in 42 (52.5%) lesion shrinked, in 36 (45%) stabilization was observed. Clinical examination revealed improvement of visual function in 15 patients (18%) and deterioration in 2 (2.5%). No new neuropathies were found. Stereotactic radiation treatment is the method of choice for medial anterior and middle fossa meningiomas due to effective control of tumor progression and minimal rate of complications. PMID:20429360

  2. Vertebral compression fractures after stereotactic body radiation therapy: a large, multi-institutional, multinational evaluation.

    PubMed

    Jawad, Maha Saada; Fahim, Daniel K; Gerszten, Peter C; Flickinger, John C; Sahgal, Arjun; Grills, Inga S; Sheehan, Jason; Kersh, Ronald; Shin, John; Oh, Kevin; Mantel, Frederick; Guckenberger, Matthias

    2016-06-01

    OBJECTIVE The purpose of this study was to identify factors contributing to an increased risk for vertebral compression fracture (VCF) following stereotactic body radiation therapy (SBRT) for spinal tumors. METHODS A total of 594 tumors were treated with spinal SBRT as primary treatment or re-irradiation at 8 different institutions as part of a multi-institutional research consortium. Patients underwent LINAC-based, image-guided SBRT to a median dose of 20 Gy (range 8-40 Gy) in a median of 1 fraction (range 1-5 fractions). Median patient age was 62 years. Seventy-one percent of tumors were osteolytic, and a preexisting vertebral compression fracture (VCF) was present in 24% of cases. Toxicity was assessed following treatment. Univariate and multivariate analyses were performed using a logistic regression method to determine parameters predictive for post-SBRT VCF. RESULTS At a median follow-up of 10.1 months (range 0.03-57 months), 80% of patients had local tumor control. At the time of last imaging follow-up, at a median of 8.8 months after SBRT, 3% had a new VCF, and 2.7% had a progressive VCF. For development of any (new or progressive) VCF following SBRT, the following factors were predictive for VCF on univariate analysis: short interval from primary diagnosis to SBRT (less than 36.8 days), solitary metastasis, no additional bone metastases, no prior chemotherapy, preexisting VCF, no MRI used for target delineation, tumor volume of 37.3 cm(3) or larger, equivalent 2-Gy-dose (EQD2) tumor of 41.8 Gy or more, and EQD2 spinal cord Dmax of 46.1 Gy or more. Preexisting VCF, solitary metastasis, and prescription dose of 38.4 Gy or more were predictive on multivariate analysis. The following factors were predictive of a new VCF on univariate analysis: solitary metastasis, no additional bone metastases, and no MRI used for target delineation. Presence of a solitary metastasis and lack of MRI for target delineation remained significant on multivariate analysis

  3. Statistical analysis of target motion in gated lung stereotactic body radiation therapy

    NASA Astrophysics Data System (ADS)

    Zhao, Bo; Yang, Yong; Li, Tianfang; Li, Xiang; Heron, Dwight E.; Saiful Huq, M.

    2011-03-01

    An external surrogate-based respiratory gating technique is a useful method to reduce target margins for the treatment of a moving lung tumor. The success of this technique relies on a good correlation between the motion of the external markers and the internal tumor as well as the repeatability of the respiratory motion. In gated lung stereotactic body radiation therapy (SBRT), the treatment time for each fraction could exceed 30 min due to large fractional dose. Tumor motion may experience pattern changes such as baseline shift during such extended treatment time. The purpose of this study is to analyze tumor motion traces in actual treatment situations and to evaluate the effect of the target baseline shift in gated lung SBRT treatment. Real-time motion data for both the external markers and tumors from 51 lung SBRT treatments with Cyberknife Synchrony technology were analyzed in this study. The treatment time is typically greater than 30 min. The baseline shift was calculated with a rolling average window equivalent to ~20 s and subtracted from that at the beginning. The magnitude of the baseline shift and its relationship with treatment time were investigated. Phase gating simulation was retrospectively performed on 12 carefully selected treatments with respiratory amplitude larger than 5 mm and regular phases. A customized gating window was defined for each individual treatment. It was found that the baseline shifts are specific to each patient and each fraction. Statistical analysis revealed that more than 69% treatments exhibited increased baseline shifts with the lapse of treatment time. The magnitude of the baseline shift could reach 5.3 mm during a 30 min treatment. Gating simulation showed that tumor excursion was caused mainly by the uncertainties in phase gating simulation and baseline shift, the latter being the primary factor. With a 5 mm gating window, 2 out of 12 treatments in the study group showed significant tumor excursion. Baseline shifts

  4. Long-term outcome of stereotactic radiosurgery (Srs) in patients with acoustic neuromas

    SciTech Connect

    Combs, Stephanie E. . E-mail: Stephanie.Combs@med.uni-heidelberg.de; Thilmann, Christoph; Debus, Juergen; Schulz-Ertner, Daniela

    2006-04-01

    Purpose: To evaluate the effectiveness and long-term outcome of stereotactic radiosurgery (SRS) for acoustic neuromas (AN). Patients and Methods: Between 1990 and 2001, we treated 26 patients with 27 AN with SRS. Two patients suffered from neurofibromatosis type 2. Before SRS, a subtotal or total resection had been performed in 3 and in 5 patients, respectively. For SRS, a median single dose of 13 Gy/80% isodose was applied. Results: The overall actuarial 5-year and 10-year tumor control probability in all patients was 91%. Two patients developed tumor progression after SRS at 36 and 48 months. Nineteen patients (73%) were at risk of treatment-related facial nerve toxicity; of these, 1 patient developed a complete facial nerve palsy after SRS (5%). A total of 93% of the lesions treated were at risk of radiation-induced trigeminal neuralgia. Two patients (8%) developed mild dysesthesia of the trigeminal nerve after SRS. The hearing preservation rate in patients with useful hearing before SRS was 55% at 9 years. Conclusion:: Stereotactic radiosurgery results in good local control rates of AN and the risk of cranial nerve toxicities is acceptable. As toxicity is lower with fractionated stereotactic radiotherapy, SRS should be reserved for smaller lesions.

  5. Hypofractionated Radiotherapy and Stereotactic Boost with Concurrent and Adjuvant Temozolamide for Glioblastoma in Good Performance Status Elderly Patients – Early Results of a Phase II Trial

    PubMed Central

    Floyd, Scott R.; Kasper, Ekkehard M.; Uhlmann, Erik J.; Fonkem, Ekokobe; Wong, Eric T.; Mahadevan, Anand

    2012-01-01

    Glioblastoma Multiforme (GBM) is an aggressive primary brain neoplasm with dismal prognosis. Based on successful phase III trials, 60 Gy involved-field radiotherapy in 30 fractions over 6 weeks [Standard radiation therapy (RT)] with concurrent and adjuvant temozolomide is currently the standard of care. In this disease, age and Karnofsky Performance Status (KPS) are the most important prognostic factors. For elderly patients, clinical trials comparing standard RT with radiotherapy abbreviated to 40 Gy in 15 fractions over 3 weeks demonstrated similar outcomes, indicating shortened radiotherapy may be an appropriate option for elderly patients. However, these trials did not include temozolomide chemotherapy, and included patients with poor KPS, possibly obscuring benefits of more aggressive treatment for some elderly patients. We conducted a prospective Phase II trial to examine the efficacy of a hypofractionated radiation course followed by a stereotactic boost with concurrent and adjuvant temozolomide chemotherapy in elderly patients with good performance status. In this study, patients 65 years and older with a KPS > 70 and histologically confirmed GBM received 40 Gy in 15 fractions with 3D conformal technique followed by a 1–3 fraction stereotactic boost to the enhancing tumor. All patients also received concurrent and adjuvant temozolomide. Patients were evaluated 1 month post-treatment and every 2 months thereafter. Between 2007 and 2010, 20 patients (9 males and 11 females) were enrolled in this study. The median age was 75.4 years (range 65–87 years). At a median follow-up of 11 months (range 7–32 months), 12 patients progressed and 5 are alive. The median progression free survival was 11 months and the median overall survival was 13 months. There was no additional toxicity. These results indicate that elderly patients with good KPS can achieve outcomes comparable to the current standard of care using an abbreviated

  6. Dose-Response Relationship for Image-Guided Stereotactic Body Radiotherapy of Pulmonary Tumors: Relevance of 4D Dose Calculation

    SciTech Connect

    Guckenberger, Matthias Wulf, Joern; Mueller, Gerd; Krieger, Thomas; Baier, Kurt; Gabor, Manuela; Richter, Anne; Wilbert, Juergen; Flentje, Michael

    2009-05-01

    Purpose: To evaluate outcome after image-guided stereotactic body radiotherapy (SBRT) for early-stage non-small-cell lung cancer (NSCLC) and pulmonary metastases. Methods and Materials: A total of 124 patients with 159 pulmonary lesions (metastases n = 118; NSCLC, n = 41; Stage IA, n = 13; Stage IB, n = 19; T3N0, n = 9) were treated with SBRT. Patients were treated with hypofractionated schemata (one to eight fractions of 6-26 Gy); biologic effective doses (BED) to the clinical target volume (CTV) were calculated based on four-dimensional (4D) dose calculation. The position of the pulmonary target was verified using volume imaging before all treatments. Results: With mean/median follow-up of 18/14 months, actuarial local control was 83% at 36 months with no difference between NSCLC and metastases. The dose to the CTV based on 4D dose calculation was closely correlated with local control: local control rates were 89% and 62% at 36 months for >100 Gy and <100 Gy BED (p = 0.0001), respectively. Actuarial freedom from regional and systemic progression was 34% at 36 months for primary NSCLC group; crude rate of regional failure was 15%. Three-year overall survival was 37% for primary NSCLC and 16% for metastases; no dose-response relationship for survival was observed. Exacerbation of comorbidities was the most frequent cause of death for primary NSCLC. Conclusions: Doses of >100 Gy BED to the CTV based on 4D dose calculation resulted in excellent local control rates. This cutoff dose is not specific to the treatment technique and protocol of our study and may serve as a general recommendation.

  7. Stereotactic radiosurgery for gynecologic cancer.

    PubMed

    Kunos, Charles; Brindle, James M; Debernardo, Robert

    2012-01-01

    Stereotactic body radiotherapy (SBRT) distinguishes itself by necessitating more rigid patient immobilization, accounting for respiratory motion, intricate treatment planning, on-board imaging, and reduced number of ablative radiation doses to cancer targets usually refractory to chemotherapy and conventional radiation. Steep SBRT radiation dose drop-off permits narrow 'pencil beam' treatment fields to be used for ablative radiation treatment condensed into 1 to 3 treatments. Treating physicians must appreciate that SBRT comes at a bigger danger of normal tissue injury and chance of geographic tumor miss. Both must be tackled by immobilization of cancer targets and by high-precision treatment delivery. Cancer target immobilization has been achieved through use of indexed customized Styrofoam casts, evacuated bean bags, or body-fix molds with patient-independent abdominal compression.(1-3) Intrafraction motion of cancer targets due to breathing now can be reduced by patient-responsive breath hold techniques,(4) patient mouthpiece active breathing coordination,(5) respiration-correlated computed tomography,(6) or image-guided tracking of fiducials implanted within and around a moving tumor.(7-9) The Cyberknife system (Accuray [Sunnyvale, CA]) utilizes a radiation linear accelerator mounted on a industrial robotic arm that accurately follows patient respiratory motion by a camera-tracked set of light-emitting diodes (LED) impregnated on a vest fitted to a patient.(10) Substantial reductions in radiation therapy margins can be achieved by motion tracking, ultimately rendering a smaller planning target volumes that are irradiated with submillimeter accuracy.(11-13) Cancer targets treated by SBRT are irradiated by converging, tightly collimated beams. Resultant radiation dose to cancer target volume histograms have a more pronounced radiation "shoulder" indicating high percentage target coverage and a small high-dose radiation "tail." Thus, increased target conformality

  8. Stereotactic body radiation therapy for prostate cancer: Rational and reasonable.

    PubMed

    Kupelian, Patrick; Mehta, Niraj H; King, Chris; Steinberg, Michael; Finkelstein, Steven E; Fernandez, Eduardo

    2015-01-01

    Stereotactic body radiation therapy (SBRT), a treatment procedure that uses large doses per fraction, is currently being used to treat prostate cancer with external radiation therapy in 4 to 5 treatments. Published series in the clinical use of SBRT in patients with localized prostate cancer demonstrate high efficacy within the available follow-up time periods. Rectal and sexual toxicity profiles have been favorable compared with other radiation techniques and surgery. Urinary toxicity profiles might be more comparable to those observed with brachytherapy, more pronounced in the acute setting. SBRT is technically more challenging, requiring precise geometric targeting with in-room image guidance. The use of large doses per fraction potentially provides unique biological effects on both tumor and normal tissues. Immunologic responses in normal tissues, local stromal microenvironment, and specific antigen-presenting cells induced by such high doses likely contribute to effective tumor kill. Ultimately, SBRT for prostate cancer offers significant logistical advantages, with increased convenience to patients and decreased overall cost to the health care delivery system. PMID:25413392

  9. In vivo biological effects of stereotactic radiosurgery: A primate model

    SciTech Connect

    Lunsford, L.D.; Altschuler, E.M.; Flickinger, J.C.; Wu, A.; Martinez, A.J. )

    1990-09-01

    Single-fraction, closed skull, small-volume irradiation (radiosurgery) of intact intracranial structures requires accurate knowledge of radiation tolerance. We have developed a baboon model to assess the in vivo destructive radiobiological effects of stereotactic radiosurgery. Three baboons received a single-fraction, 150-Gy lesion of the caudate nucleus, the thalamus, or the pons using the 8-mm diameter collimator of the gamma unit. Serial standard neurodiagnostic tests (neurological examination, computed tomographic scan, magnetic resonance imaging, stable xenon-enhanced computed tomographic scan of cerebral blood flow, somatosensory and brain stem evoked potentials, and myelin basic protein levels of cerebrospinal fluid) were compared with preoperative studies. Magnetic resonance imaging revealed the development of a lesion at the target site between 45 and 60 days after irradiation. Deterioration of the brain stem evoked potentials preceded imaging changes when the lesion encroached on auditory pathways. Myelin basic protein levels increased subsequent to imaging changes. Postmortem neuropathological examination confirmed a well-demarcated radionecrosis of the target volume. The baboon model appears to be an excellent method to study the in vivo biological effects of radiosurgery.

  10. Stereotactic Body Radiation Therapy Boost in Locally Advanced Pancreatic Cancer

    SciTech Connect

    Seo, Young Seok; Kim, Mi-Sook; Yoo, Sung Yul; Cho, Chul Koo; Yang, Kwang Mo; Yoo, Hyung Jun; Choi, Chul Won; Lee, Dong Han; Kim, Jin; Kim, Min Suk; Kang, Hye Jin; Kim, YoungHan

    2009-12-01

    Purpose: To investigate the clinical application of a stereotactic body radiation therapy (SBRT) boost in locally advanced pancreatic cancer patients with a focus on local efficacy and toxicity. Methods and Materials: We retrospectively reviewed 30 patients with locally advanced and nonmetastatic pancreatic cancer who had been treated between 2004 and 2006. Follow-up duration ranged from 4 to 41 months (median, 14.5 months). A total dose of 40 Gy was delivered in 20 fractions using a conventional three-field technique, and then a single fraction of 14, 15, 16, or 17 Gy SBRT was administered as a boost without a break. Twenty-one patients received chemotherapy. Overall and local progression-free survival were calculated and prognostic factors were evaluated. Results: One-year overall survival and local progression-free survival rates were 60.0% and 70.2%, respectively. One patient (3%) developed Grade 4 toxicity. Carbohydrate antigen 19-9 response was found to be an independent prognostic factor for survival. Conclusions: Our findings indicate that a SBRT boost provides a safe means of increasing radiation dose. Based on the results of this study, we recommend that a well controlled Phase II study be conducted on locally advanced pancreatic cancer.

  11. Stereotactic radiosurgery of deeply seated low grade gliomas.

    PubMed

    Barcia, J A; Barcia-Salorio, J L; Ferrer, C; Ferrer, E; Algás, R; Hernández, G

    1994-01-01

    The authors report the results of a series of 16 cases of low-grade gliomas in whom radiosurgery was performed. This series started in 1977. All the tumours received a single radiosurgical session (with a mean dose of 21.7 Gy, 5-10 mm. collimator; one patient received two sessions and in another patient two different targets were irradiated in the same session). Prior to radiosurgery, six patients received conventional external fractionated radiotherapy, with two lateral fields of up to 10 x 10 cm. and a mean dose of 55.1 Gy and another six patients with tumours less than 5 cm. in diameter, received stereotactic radiotherapy using four fields of up to 5 x 5 cm. and a mean dose of 53.1 Gy. In both cases, conventional fractionation was used, giving a dose of 1.8 to 2 Gy/day. The tumour disappeared in 8 cases (50%) and shunk or ceased its growth in 5 additional cases (31%). In 3 cases of brainstem gliomas in which the clinical condition was previously very poor there was no evolutional change and the patients eventually died. We conclude that radiosurgery is effective in the treatment of deeply seated low-grade gliomas, where it may become the treatment of choice in the absence of other more definitive choices. PMID:7717138

  12. Acceptance testing prone stereotactic breast biopsy units.

    PubMed

    Kimme-Smith, C; Solberg, T

    1994-07-01

    When the Mammography Quality Standards Act becomes law in October, 1994, stereotactic breast biopsy units may require yearly physicist calibration. Upright stereotactic units can be easily tested using conventional mammography procedures and a gelatin phantom containing simulated calcifications, but prone units are difficult to assess because of the under-table tube configuration. The two current manufacturers of these units have made different design decisions which affect each unit's calibration. There are a number of important distinctions between screening and prone biopsy units. For the two currently available prone units, a pronounced heel effect makes ion chamber position critical. Focal spot measurements are particularly difficult on one unit because there is no light field. The fixed grid on the other unit must be tested with a flood film. Physicists who inspect these units before their clinical use should be aware of variations needed by this equipment for specific acceptance tests. PMID:7968854

  13. Stereotactic Body Radiation Therapy Can Be Used Safely to Boost Residual Disease in Locally Advanced Non-Small Cell Lung Cancer: A Prospective Study

    SciTech Connect

    Feddock, Jonathan; Arnold, Susanne M.; Shelton, Brent J.; Sinha, Partha; Conrad, Gary; Chen, Li; Rinehart, John; McGarry, Ronald C.

    2013-04-01

    Purpose: To report the results of a prospective, single-institution study evaluating the feasibility of conventional chemoradiation (CRT) followed by stereotactic body radiation therapy (SBRT) as a means of dose escalation for patients with stage II-III non-small cell lung cancer (NSCLC) with residual disease. Methods and Materials: Patients without metastatic disease and with radiologic evidence of limited residual disease (≤5 cm) within the site of the primary tumor and good or complete nodal responses after standard CRT to a target dose of 60 Gy were considered eligible. The SBRT boost was done to achieve a total combined dose biological equivalent dose >100 Gy to the residual primary tumor, consisting of 10 Gy × 2 fractions (20 Gy total) for peripheral tumors, and 6.5 Gy × 3 fractions (19.5 Gy total) for medial tumors using the Radiation Therapy Oncology Group protocol 0813 definitions. The primary endpoint was the development of grade ≥3 radiation pneumonitis (RP). Results: After a median follow-up of 13 months, 4 patients developed acute grade 3 RP, and 1 (2.9%) developed late and persistent grade 3 RP. No patients developed grade 4 or 5 RP. Mean lung dose, V2.5, V5, V10, and V20 values were calculated for the SBRT boost, and none were found to significantly predict for RP. Only advancing age (P=.0147), previous smoking status (P=.0505), and high CRT mean lung dose (P=.0295) were significantly associated with RP development. At the time of analysis, the actuarial local control rate at the primary tumor site was 82.9%, with only 6 patients demonstrating recurrence. Conclusions: Linear accelerator-based SBRT for dose escalation of limited residual NSCLC after definitive CRT was feasible and did not increase the risk for toxicity above that for standard radiation therapy.

  14. Stereotactic Mesencephalotomy for Cancer - Related Facial Pain

    PubMed Central

    Kim, Deok-ryeong; Lee, Sang-won

    2014-01-01

    Cancer-related facial pain refractory to pharmacologic management or nondestructive means is a major indication for destructive pain surgery. Stereotactic mesencephalotomy can be a valuable procedure in the management of cancer pain involving the upper extremities or the face, with the assistance of magnetic resonance imaging (MRI) and electrophysiologic mapping. A 72-year-old man presented with a 3-year history of intractable left-sided facial pain. When pharmacologic and nondestructive measures failed to provide pain alleviation, he was reexamined and diagnosed with inoperable hard palate cancer with intracranial extension. During the concurrent chemoradiation treatment, his cancer-related facial pain was aggravated and became medically intractable. After careful consideration, MRI-based stereotactic mesencephalotomy was performed at a point 5 mm behind the posterior commissure, 6 mm lateral to and 5 mm below the intercommissural plane using a 2-mm electrode, with the temperature of the electrode raised to 80℃ for 60 seconds. Up until now, the pain has been relatively well-controlled by intermittent intraventricular morphine injection and oral opioids, with the pain level remaining at visual analogue scale 4 or 5. Stereotactic mesencephalotomy with the use of high-resolution MRI and electrophysiologic localization is a valuable procedure in patients with cancer-related facial pain. PMID:25289131

  15. Stereotactic catheter placement for Ommaya reservoirs.

    PubMed

    Kennedy, Benjamin C; Brown, Lauren T; Komotar, Ricardo J; McKhann, Guy M

    2016-05-01

    Ommaya reservoirs are an important surgical therapy for the chronic intrathecal administration of chemotherapy for patients with leptomeningeal carcinomatosis. Surgical accuracy is paramount in these patients with typically normal sized ventricles, and may be improved with stereotactic guidance. This paper aimed to review a large series of stereotactic Ommaya catheter placements, examining accuracy and complications. We conducted a retrospective review of 109 consecutive adult patients who underwent stereotactic Ommaya catheter placement for leptomeningeal carcinomatosis or central nervous system lymphoma at Columbia University Medical Center, USA, from 1998-2013. The rate of accurate placement in the ventricular system was 99%, with the only poor catheter position due to post-placement migration. The rate of peri-operative complications was 6.4%. Hemorrhagic complications occurred in patients with thrombocytopenia or therapeutic anti-coagulation pre-operatively or during the post-operative period. Use of stereotaxy for catheter placement of Ommaya reservoirs is safe and effective, and should be considered when placing a catheter into non-hydrocephalic ventricles. PMID:26778516

  16. STOCK AND DISTRIBUTION OF TOTAL AND CORN-DERIVED SOIL ORGANIC CARBON IN AGGREGATE AND PRIMARY PARTICLE FRACTIONS FOR DIFFERENT LAND USE AND SOIL MANAGEMENT PRACTICES

    SciTech Connect

    Puget, P; Lal, Rattan; Izaurralde, R Cesar C.; Post, M; Owens, Lloyd

    2005-04-01

    Land use, soil management, and cropping systems affect stock, distribution, and residence time of soil organic carbon (SOC). Therefore, SOC stock and its depth distribution and association with primary and secondary particles were assessed in long-term experiments at the North Appalachian Experimental Watersheds near Coshocton, Ohio, through *13C techniques. These measurements were made for five land use and soil management treatments: (1) secondary forest, (2) meadow converted from no-till (NT) corn since 1988, (3) continuous NT corn since 1970, (4) continuous NT corn-soybean in rotation with ryegrass since 1984, and (5) conventional plow till (PT) corn since 1984. Soil samples to 70-cm depth were obtained in 2002 in all treatments. Significant differences in soil properties were observed among land use treatments for 0 to 5-cm depth. The SOC concentration (g C kg*1 of soil) in the 0 to 5-cm layer was 44.0 in forest, 24.0 in meadow, 26.1 in NT corn, 19.5 in NT corn-soybean, and 11.1 i n PT corn. The fraction of total C in corn residue converted to SOC was 11.9% for NT corn, 10.6% for NT corn-soybean, and 8.3% for PT corn. The proportion of SOC derived from corn residue was 96% for NT corn in the 0 to 5-cm layer, and it decreased gradually with depth and was 50% in PT corn. The mean SOC sequestration rate on conversion from PT to NT was 280 kg C ha*1 y*1. The SOC concentration decreased with reduction in aggregate size, and macro-aggregates contained 15 to 35% more SOC concentration than microaggregates. In comparison with forest, the magnitude of SOC depletion in the 0 to 30-cm layer was 15.5 Mg C/ha (24.0%) in meadow, 12.7 Mg C/ha (19.8%) in NT corn, 17.3 Mg C/ha (26.8%) in NT corn-soybean, and 23.3 Mg C/ha (35.1%) in PT corn. The SOC had a long turnover time when located deeper in the subsoil.

  17. Stereotactically-navigated percutaneous Irreversible Electroporation (IRE) compared to conventional IRE: a prospective trial

    PubMed Central

    Pregler, Benedikt; Nießen, Christoph; Schicho, Andreas; Haimerl, Michael; Jung, Ernst Michael; Stroszczynski, Christian; Wiggermann, Philipp

    2016-01-01

    Purpose. The purpose of this study was to compare CT-navigated stereotactic IRE (SIRE) needle placement to non-navigated conventional IRE (CIRE) for percutaneous ablation of liver malignancies. Materials and Methods. A prospective trial including a total of 20 patients was conducted with 10 patients in each arm of the study. IRE procedures were guided using either CT fluoroscopy (CIRE) or a stereotactic planning and navigation system (SIRE). Primary endpoint was procedure time. Secondary endpoints were accuracy of needle placement, technical success rate, complication rate and dose-length product (DLP). Results. A total of 20 IRE procedures were performed to ablate hepatic malignancies (16 HCC, 4 liver metastases), 10 procedures in each arm. Mean time for placement of IRE electrodes in SIRE was significantly shorter with 27 ± 8 min compared to 87 ± 30 min for CIRE (p < 0.001). Accuracy of needle placement for SIRE was higher than CIRE (2.2 mm vs. 3.3 mm mean deviation, p < 0.001). The total DLP and the fluoroscopy DLP were significantly lower in SIRE compared to CIRE. Technical success rate and complication rates were equal in both arms. Conclusion. SIRE demonstrated a significant reduction of procedure length and higher accuracy compared to CIRE. Stereotactic navigation has the potential to reduce radiation dose for the patient and the radiologist without increasing the risk of complications or impaired technical success compared to CIRE. PMID:27602266

  18. Stereotactically-navigated percutaneous Irreversible Electroporation (IRE) compared to conventional IRE: a prospective trial.

    PubMed

    Beyer, Lukas P; Pregler, Benedikt; Nießen, Christoph; Schicho, Andreas; Haimerl, Michael; Jung, Ernst Michael; Stroszczynski, Christian; Wiggermann, Philipp

    2016-01-01

    Purpose. The purpose of this study was to compare CT-navigated stereotactic IRE (SIRE) needle placement to non-navigated conventional IRE (CIRE) for percutaneous ablation of liver malignancies. Materials and Methods. A prospective trial including a total of 20 patients was conducted with 10 patients in each arm of the study. IRE procedures were guided using either CT fluoroscopy (CIRE) or a stereotactic planning and navigation system (SIRE). Primary endpoint was procedure time. Secondary endpoints were accuracy of needle placement, technical success rate, complication rate and dose-length product (DLP). Results. A total of 20 IRE procedures were performed to ablate hepatic malignancies (16 HCC, 4 liver metastases), 10 procedures in each arm. Mean time for placement of IRE electrodes in SIRE was significantly shorter with 27 ± 8 min compared to 87 ± 30 min for CIRE (p < 0.001). Accuracy of needle placement for SIRE was higher than CIRE (2.2 mm vs. 3.3 mm mean deviation, p < 0.001). The total DLP and the fluoroscopy DLP were significantly lower in SIRE compared to CIRE. Technical success rate and complication rates were equal in both arms. Conclusion. SIRE demonstrated a significant reduction of procedure length and higher accuracy compared to CIRE. Stereotactic navigation has the potential to reduce radiation dose for the patient and the radiologist without increasing the risk of complications or impaired technical success compared to CIRE. PMID:27602266

  19. Poster — Thur Eve — 32: Stereotactic Body Radiation Therapy for Peripheral Lung Lesion: Treatment Planning and Quality Assurance

    SciTech Connect

    Wan, Shuying; Oliver, Michael; Wang, Xiaofang

    2014-08-15

    Stereotactic body radiation therapy (SBRT), due to its high precision for target localizing, has become widely used to treat tumours at various locations, including the lungs. Lung SBRT program was started at our institution a year ago. Eighteen patients with peripheral lesions up to 3 cm diameter have been treated with 48 Gy in 4 fractions. Based on four-dimensional computed tomography (4DCT) simulation, internal target volume (ITV) was delineated to encompass the respiratory motion of the lesion. A margin of 5 mm was then added to create the planning target volume (PTV) for setup uncertainties. There was no expansion from gross tumour volume (GTV) to clinical target volume (CTV). Pinnacle 9.6 was used as the primary treatment planning system. Volumetric modulated arc therapy (VMAT) technique, with one or two coplanar arcs, generally worked well. For quality assurance (QA), each plan was exported to Eclipse 10 and dose calculation was repeated. Dose volume histograms (DVHs) of the targets and organs at risk (OARs) were then compared between the two treatment planning systems. Winston-Lutz tests were carried out as routine machine QA. Patient-specific QA included ArcCheck measurement with an insert, where an ionization chamber was placed at the centre to measure dose at the isocenter. For the first several patients, and subsequently for the plans with extremely strong modulation, Gafchromic film dosimetry was also employed. For each patient, a mock setup was scheduled prior to treatments. Daily pre- and post-CBCT were acquired for setup and assessment of intra-fractional motion, respectively.

  20. The role of stereotactic radiosurgery in the treatment of intramedullary spinal cord neoplasms: a systematic literature review.

    PubMed

    Hernández-Durán, Silvia; Hanft, Simon; Komotar, Ricardo J; Manzano, Glen R

    2016-04-01

    Advances in imaging technology and microsurgical techniques have made microsurgical resection the treatment of choice in cases of symptomatic intramedullary tumors. The use of stereotactic radiosurgery (SRS) for spinal tumors is a recent development, and its application to intramedullary lesions is debated. We conducted a literature search through PubMed's MeSH system, compiling information regarding intramedullary neoplasms treated by SRS. We compiled histology, tumor location and size, treatment modality, radiation dose, fractionation, radiation-induced complications, follow-up, and survival. Ten papers reporting on 52 patients with 70 tumors were identified. Metastatic lesions accounted for 33 %, while 67 % were primary ones. Tumor location was predominantly cervical (53 %), followed by thoracic (33 %). Mean volume was 0.55 cm(3) (95 % confidence interval (CI), 0.26-0.83). Preferred treatment modality was CyberKnife® (87 %), followed by Novalis® (7 %) and linear particle accelerator (LINAC) (6 %). Mean radiation dose was 22.14 Gy (95 % CI, 20.75-23.53), with mean fractionation of 4 (95 % CI, 3-5). Three hemangioblastomas showed cyst enlargement. Symptom improvement or stabilization was seen in all but two cases. Radionecrotic spots adjacent to treated areas were seen at autopsy in four lesions, without clinical manifestations. Overall, clinical and radiological outcomes were favorable. Although surgery remains the treatment of choice for symptomatic intramedullary lesions, SRS can be a safe and effective option in selected cases. While this review suggests the overall safety and efficacy of SRS in the management of intramedullary tumors, future studies need randomized, homogeneous patient populations followed over a longer period to provide more robust evidence in its favor. PMID:26219855

  1. Treatment of Five or More Brain Metastases With Stereotactic Radiosurgery

    SciTech Connect

    Hunter, Grant K.; Suh, John H.; Reuther, Alwyn M.; Vogelbaum, Michael A.; Barnett, Gene H.; Angelov, Lilyana; Weil, Robert J.; Neyman, Gennady; Chao, Samuel T.

    2012-08-01

    Purpose: To examine the outcomes of patients with five or more brain metastases treated in a single session with stereotactic radiosurgery (SRS). Methods and Materials: Sixty-four patients with brain metastases treated with SRS to five or more lesions in a single session were reviewed. Primary disease type, number of lesions, Karnofsky performance score (KPS) at SRS, and status of primary and systemic disease at SRS were included. Patients were treated using dosing as defined by Radiation Therapy Oncology Group Protocol 90-05, with adjustments for critical structures. We defined prior whole-brain radiotherapy (WBRT) as WBRT completed >1 month before SRS and concurrent WBRT as WBRT completed within 1 month before or after SRS. Kaplan-Meier estimates and Cox proportional hazard regression were used to determine which patient and treatment factors predicted overall survival (OS). Results: The median OS after SRS was 7.5 months. The median KPS was 80 (range, 60-100). A KPS of {>=}80 significantly influenced OS (median OS, 4.8 months for KPS {<=}70 vs. 8.8 months for KPS {>=}80, p = 0.0097). The number of lesions treated did not significantly influence OS (median OS, 6.6 months for eight or fewer lesions vs. 9.9 months for more than eight, p = nonsignificant). Primary site histology did not significantly influence median OS. On multivariate Cox modeling, KPS and prior WBRT significantly predicted for OS. Whole-brain radiotherapy before SRS compared with concurrent WBRT significantly influenced survival, with a risk ratio of 0.423 (95% confidence interval 0.191-0.936, p = 0.0338). No significant differences were observed when no WBRT was compared with concurrent WBRT or when the no WBRT group was compared with prior WBRT. A KPS of {<=}70 predicted for poorer outcomes, with a risk ratio of 2.164 (95% confidence interval 1.157-4.049, p = 0.0157). Conclusions: Stereotactic radiosurgery to five or more brain lesions is an effective treatment option for patients with

  2. Predictors of Toxicity Associated With Stereotactic Body Radiation Therapy to the Central Hepatobiliary Tract

    SciTech Connect

    Osmundson, Evan C.; Wu, Yufan; Luxton, Gary; Bazan, Jose G.; Koong, Albert C.; Chang, Daniel T.

    2015-04-01

    Purpose: To identify dosimetric predictors of hepatobiliary (HB) toxicity associated with stereotactic body radiation therapy (SBRT) for liver tumors. Methods and Materials: We retrospectively reviewed 96 patients treated with SBRT for primary (53%) or metastatic (47%) liver tumors between March 2006 and November 2013. The central HB tract (cHBT) was defined by a 15-mm expansion of the portal vein from the splenic confluence to the first bifurcation of left and right portal veins. Patients were censored for toxicity upon local progression or additional liver-directed therapy. HB toxicities were graded according to Common Terminology Criteria for Adverse Events version 4.0. To compare different SBRT fractionations, doses were converted to biologically effective doses (BED) by using the standard linear quadratic model α/β = 10 (BED10). Results: Median follow-up was 12.7 months after SBRT. Median BED10 was 85.5 Gy (range: 37.5-151.2). The median number of fractions was 5 (range: 1-5), with 51 patients (53.1%) receiving 5 fractions and 29 patients (30.2%) receiving 3 fractions. In total, there were 23 (24.0%) grade 2+ and 18 (18.8%) grade 3+ HB toxicities. Nondosimetric factors predictive of grade 3+ HB toxicity included cholangiocarcinoma (CCA) histology (P<.0001), primary liver tumor (P=.0087), and biliary stent (P<.0001). Dosimetric parameters most predictive of grade 3+ HB toxicity were volume receiving above BED10 of 72 Gy (V{sub BED10}72) ≥ 21 cm{sup 3} (relative risk [RR]: 11.6, P<.0001), V{sub BED10}66 ≥ 24 cm{sup 3} (RR: 10.5, P<.0001), and mean BED10 (Dmean{sub BED10}) cHBT ≥14 Gy (RR: 9.2, P<.0001), with V{sub BED10}72 and V{sub BED10}66 corresponding to V40 and V37.7 for 5 fractions and V33.8 and V32.0 for 3 fractions, respectively. V{sub BED10}72 ≥ 21 cm{sup 3}, V{sub BED10}66 ≥ 24 cm{sup 3}, and Dmean{sub BED10} cHBT ≥14 Gy were consistently predictive of grade 3+ toxicity on multivariate analysis. Conclusions: V

  3. First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV.

    PubMed

    Aguilar, M; Alberti, G; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Anderhub, H; Arruda, L; Azzarello, P; Bachlechner, A; Barao, F; Baret, B; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Basili, A; Batalha, L; Bates, J; Battiston, R; Bazo, J; Becker, R; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Berges, P; Bertucci, B; Bigongiari, G; Biland, A; Bindi, V; Bizzaglia, S; Boella, G; de Boer, W; Bollweg, K; Bolmont, J; Borgia, B; Borsini, S; Boschini, M J; Boudoul, G; Bourquin, M; Brun, P; Buénerd, M; Burger, J; Burger, W; Cadoux, F; Cai, X D; Capell, M; Casadei, D; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, C R; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chernoplyiokov, N; Chikanian, A; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Commichau, V; Consolandi, C; Contin, A; Corti, C; Costado Dios, M T; Coste, B; Crespo, D; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirkoz, B; Dennett, P; Derome, L; Di Falco, S; Diao, X H; Diago, A; Djambazov, L; Díaz, C; von Doetinchem, P; Du, W J; Dubois, J M; Duperay, R; Duranti, M; D'Urso, D; Egorov, A; Eline, A; Eppling, F J; Eronen, T; van Es, J; Esser, H; Falvard, A; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Flood, K; Foglio, R; Fohey, M; Fopp, S; Fouque, N; Galaktionov, Y; Gallilee, M; Gallin-Martel, L; Gallucci, G; García, B; García, J; García-López, R; García-Tabares, L; Gargiulo, C; Gast, H; Gebauer, I; Gentile, S; Gervasi, M; Gillard, W; Giovacchini, F; Girard, L; Goglov, P; Gong, J; Goy-Henningsen, C; Grandi, D; Graziani, M; Grechko, A; Gross, A; Guerri, I; de la Guía, C; Guo, K H; Habiby, M; Haino, S; Hauler, F; He, Z H; Heil, M; Heilig, J; Hermel, R; Hofer, H; Huang, Z C; Hungerford, W; Incagli, M; Ionica, M; Jacholkowska, A; Jang, W Y; Jinchi, H; Jongmanns, M; Journet, L; Jungermann, L; Karpinski, W; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Koulemzine, A; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Laudi, E; Laurenti, G; Lauritzen, C; Lebedev, A; Lee, M W; Lee, S C; Leluc, C; León Vargas, H; Lepareur, V; Li, J Q; Li, Q; Li, T X; Li, W; Li, Z H; Lipari, P; Lin, C H; Liu, D; Liu, H; Lomtadze, T; Lu, Y S; Lucidi, S; Lübelsmeyer, K; Luo, J Z; Lustermann, W; Lv, S; Madsen, J; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masciocchi, F; Masi, N; Maurin, D; McInturff, A; McIntyre, P; Menchaca-Rocha, A; Meng, Q; Menichelli, M; Mereu, I; Millinger, M; Mo, D C; Molina, M; Mott, P; Mujunen, A; Natale, S; Nemeth, P; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oh, S; Oliva, A; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Park, W H; Pauluzzi, M; Pauss, F; Pauw, A; Pedreschi, E; Pensotti, S; Pereira, R; Perrin, E; Pessina, G; Pierschel, G; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pochon, J; Pohl, M; Poireau, V; Porter, S; Pouxe, J; Putze, A; Quadrani, L; Qi, X N; Rancoita, P G; Rapin, D; Ren, Z L; Ricol, J S; Riihonen, E; Rodríguez, I; Roeser, U; Rosier-Lees, S; Rossi, L; Rozhkov, A; Rozza, D; Sabellek, A; Sagdeev, R; Sandweiss, J; Santos, B; Saouter, P; Sarchioni, M; Schael, S; Schinzel, D; Schmanau, M; Schwering, G; Schulz von Dratzig, A; Scolieri, G; Seo, E S; Shan, B S; Shi, J Y; Shi, Y M; Siedenburg, T; Siedling, R; Son, D; Spada, F; Spinella, F; Steuer, M; Stiff, K; Sun, W; Sun, W H; Sun, X H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tassan-Viol, J; Ting, Samuel C C; Ting, S M; Titus, C; Tomassetti, N; Toral, F; Torsti, J; Tsai, J R; Tutt, J C; Ulbricht, J; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vargas Trevino, M; Vaurynovich, S; Vecchi, M; Vergain, M; Verlaat, B; Vescovi, C; Vialle, J P; Viertel, G; Volpini, G; Wang, D; Wang, N H; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Wallraff, W; Weng, Z L; Willenbrock, M; Wlochal, M; Wu, H; Wu, K Y; Wu, Z S; Xiao, W J; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J G; Zhang, Z; Zhang, M M; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zuccon, P; Zurbach, C

    2013-04-01

    A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼ 250  GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena. PMID:25166975

  4. Small Bowel Dose Tolerance for Stereotactic Body Radiation Therapy.

    PubMed

    LaCouture, Tamara A; Xue, Jinyu; Subedi, Gopal; Xu, Qianyi; Lee, Justin T; Kubicek, Gregory; Asbell, Sucha O

    2016-04-01

    Inconsistencies permeate the literature regarding small bowel dose tolerance limits for stereotactic body radiation therapy (SBRT) treatments. In this review, we organized these diverse published limits with MD Anderson at Cooper data into a unified framework, constructing the dose-volume histogram (DVH) Risk Map, demonstrating low-risk and high-risk SBRT dose tolerance limits for small bowel. Statistical models of clinical data from 2 institutions were used to assess the safety spectrum of doses used in the exposure of the gastrointestinal tract in SBRT; 30% of the analyzed cases had vascular endothelial growth factor inhibitors (VEGFI) or other biological agents within 2 years before or after SBRT. For every dose tolerance limit in the DVH Risk Map, the probit dose-response model was used to estimate the risk level from our clinical data. Using the current literature, 21Gy to 5cc of small bowel in 3 fractions has low toxicity and is reasonably safe, with 6.5% estimated risk of grade 3 or higher complications, per Common Terminology Criteria for Adverse Events version 4.0. In the same fractionation for the same volume, if lower risk is required, 16.2Gy has an estimated risk of only 2.5%. Other volumes and fractionations are also reviewed; for all analyzed high-risk small bowel limits, the risk is 8.2% or less, and the low-risk limits have 4% or lower estimated risk. The results support current clinical practice, with some possibility for dose escalation. PMID:27000513

  5. Innovative Hypofractionated Stereotactic Regimen Achieves Excellent Local Control with No Radiation Necrosis: Promising Results in the Management of Patients with Small Recurrent Inoperable GBM

    PubMed Central

    Pannullo, Susan C.; Minkowitz, Shlomo; Taube, Shoshana; Chang, Jenghwa; Parashar, Bhupesh; Christos, Paul; Wernicke, A.Gabriella

    2016-01-01

    Management of recurrent glioblastoma multiforme (GBM) remains a challenge. Several institutions reported that a single fraction of ≥ 20 Gy for small tumor burden results in excellent local control; however, this is at the expense of a high incidence of radiation necrosis (RN). Therefore, we developed a hypofractionation pattern of 33 Gy/3 fractions, which is a radiobiological equivalent of 20 Gy, with the aim to lower the incidence of RN. We reviewed records of 21 patients with recurrent GBM treated with hypofractionated stereotactic radiation therapy (HFSRT) to their 22 respective lesions. Sixty Gy fractioned external beam radiotherapy was performed as first-line treatment. Median time from primary irradiation to HFSRT was 9.6 months (range: 3.1 – 68.1 months). In HFSRT, a median dose of 33 Gy in 11 Gy fractions was delivered to the 80% isodose line that encompassed the target volume. The median tumor volume was 1.07 cm3 (range: 0.11 – 16.64 cm3). The median follow-up time after HFSRT was 9.3 months (range: 1.7 – 33.6 months). Twenty-one of 23 lesions treated (91.3%) achieved local control while 2/23 (8.7%) progressed. Median time to progression outside of the treated site was 5.2 months (range: 2.2 – 9.6 months). Progression was treated with salvage chemotherapy. Five of 21 patients (23.8%) were alive at the end of this follow-up; two patients remain disease-free. The remaining 16/21 patients (76.2%) died of disease. Treatment was well tolerated by all patients with no acute CTC/RTOG > Grade 2. There was 0% incidence of RN. A prospective trial will be underway to validate these promising results. PMID:27096136

  6. Innovative Hypofractionated Stereotactic Regimen Achieves Excellent Local Control with No Radiation Necrosis: Promising Results in the Management of Patients with Small Recurrent Inoperable GBM.

    PubMed

    Jia, Angela; Pannullo, Susan C; Minkowitz, Shlomo; Taube, Shoshana; Chang, Jenghwa; Parashar, Bhupesh; Christos, Paul; Wernicke, A Gabriella

    2016-01-01

    Management of recurrent glioblastoma multiforme (GBM) remains a challenge. Several institutions reported that a single fraction of ≥ 20 Gy for small tumor burden results in excellent local control; however, this is at the expense of a high incidence of radiation necrosis (RN). Therefore, we developed a hypofractionation pattern of 33 Gy/3 fractions, which is a radiobiological equivalent of 20 Gy, with the aim to lower the incidence of RN. We reviewed records of 21 patients with recurrent GBM treated with hypofractionated stereotactic radiation therapy (HFSRT) to their 22 respective lesions. Sixty Gy fractioned external beam radiotherapy was performed as first-line treatment. Median time from primary irradiation to HFSRT was 9.6 months (range: 3.1 - 68.1 months). In HFSRT, a median dose of 33 Gy in 11 Gy fractions was delivered to the 80% isodose line that encompassed the target volume. The median tumor volume was 1.07 cm3 (range: 0.11 - 16.64 cm3). The median follow-up time after HFSRT was 9.3 months (range: 1.7 - 33.6 months). Twenty-one of 23 lesions treated (91.3%) achieved local control while 2/23 (8.7%) progressed. Median time to progression outside of the treated site was 5.2 months (range: 2.2 - 9.6 months). Progression was treated with salvage chemotherapy. Five of 21 patients (23.8%) were alive at the end of this follow-up; two patients remain disease-free. The remaining 16/21 patients (76.2%) died of disease. Treatment was well tolerated by all patients with no acute CTC/RTOG > Grade 2. There was 0% incidence of RN. A prospective trial will be underway to validate these promising results. PMID:27096136

  7. Upfront Stereotactic Radiosurgery for Pineal Parenchymal Tumors in Adults

    PubMed Central

    Park, Jong Hoon; Kim, Jeong Hoon; Kwon, Do Hoon; Kim, Chang Jin; Khang, Shin Kwang

    2015-01-01

    Objective Pineal parenchymal tumors (PPTs) in adults are rare, and knowledge regarding their optimal management and treatment outcome is limited. Herein, we present the clinical results of our series of PPTs other than pineoblastomas managed by stereotactic radiosurgery (SRS) at upfront setting. Methods Between 1997 and 2014, nine consecutive adult patients with the diagnosis of PPTs, either pineocytoma or pineal parenchymal tumor of intermediate differentiation, were treated with SRS. There were 6 men and 3 women. The median age was 39 years (range, 31-53 years). All of the patients presented with symptoms of hydrocephalus. Endoscopic third ventriculostomy and biopsy was done for initial management. After histologic diagnosis, patients were treated with Gamma Knife with the mean dose of 13.3 Gy (n=3) or fractionated Cyberknife with 32 Gy (n=6). Results After a mean follow-up of 78.6 months (range, 14-223 months), all patients were alive and all of their tumors were locally controlled except for one instance of cerebrospinal fluid seeding metastasis. On magnetic resonance images, tumor size decreased in all patients, resulting in complete response in 3 patients and partial response in 6. One patient had experienced temporary memory impairment after SRS, which improved spontaneously. Conclusion SRS is effective and safe for PPTs in adults and can be considered as a useful alternative to surgical resection at upfront setting. PMID:26587186

  8. Stereotactic Body Radiotherapy Reirradiation for Recurrent Epidural Spinal Metastases

    SciTech Connect

    Mahadevan, Anand; Floyd, Scott; Wong, Eric; Jeyapalan, Suriya; Groff, Michael; Kasper, Ekkehard

    2011-12-01

    Purpose: When patients show progression after conventional fractionated radiation for spine metastasis, further radiation and surgery may not be options. Stereotactic body radiotherapy (SBRT) has been successfully used in treatment of the spine and may be applicable in these cases. We report the use of SBRT for 60 consecutive patients (81 lesions) who had radiological progressive spine metastasis with epidural involvement after previous radiation for spine metastasis. Methods and Materials: SBRT was used with fiducial and vertebral anatomy-based targeting. The radiation dose was prescribed based on the extent of spinal canal involvement; the dose was 8 Gy Multiplication-Sign 3 = 24 Gy when the tumor did not touch the spinal cord and 5 to 6 Gy x 5 = 25 to 30 Gy when the tumor abutted the cord. The cord surface received up to the prescription dose with no hot spots in the cord. Results: The median overall survival was 11 months, and the median progression-free survival was 9 months. Overall, 93% of patients had stable or improved disease while 7% of patients showed disease progression; 65% of patients had pain relief. There was no significant toxicity other than fatigue. Conclusions: SBRT is feasible and appears to be an effective treatment modality for reirradiation after conventional palliative radiation fails for spine metastasis patients.

  9. Stereotactic Ablative Radiotherapy for Oligometastatic Disease in Liver

    PubMed Central

    Kim, Myungsoo; Son, Seok Hyun; Won, Yong Kyun; Kay, Chul Seung

    2014-01-01

    Liver metastasis in solid tumors, including colorectal cancer, is the most frequent and lethal complication. The development of systemic therapy has led to prolonged survival. However, in selected patients with a finite number of discrete lesions in liver, defined as oligometastatic state, additional local therapies such as surgical resection, radiofrequency ablation, cryotherapy, and radiotherapy can lead to permanent local disease control and improve survival. Among these, an advance in radiation therapy made it possible to deliver high dose radiation to the tumor more accurately, without impairing the liver function. In recent years, the introduction of stereotactic ablative radiotherapy (SABR) has offered even more intensive tumor dose escalation in a few fractions with reduced dose to the adjacent normal liver. Many studies have shown that SABR for oligometastases is effective and safe, with local control rates widely ranging from 50% to 100% at one or two years. And actuarial survival at one and two years has been reported ranging from 72% to 94% and from 30% to 62%, respectively, without severe toxicities. In this paper, we described the definition and technical aspects of SABR, clinical outcomes including efficacy and toxicity, and related parameters after SABR in liver oligometastases from colorectal cancer. PMID:24868526

  10. Stereotactic Body Radiotherapy (SBRT) Reirradiation for Recurrent Pancreas Cancer

    PubMed Central

    Dagoglu, Nergiz; Callery, Mark; Moser, James; Tseng, Jennifer; Kent, Tara; Bullock, Andrea; Miksad, Rebecca; Mancias, Joseph D.; Mahadevan, Anand

    2016-01-01

    Objectives: After adjuvant or definitive radiation for pancreas cancer, there are limited conventional treatment options for recurrent pancreas cancer. We explored the role of (Stereotactic Body Radiotherapy) SBRT for reirradiation of recurrent pancreas Cancer. Methods: This is a retrospective study of patients reirradiated with SBRT for recurrent pancreas cancer. All patients were deemed unresectable and treated with systemic therapy. Fiducial gold markers were used. CT simulation was performed with oral and IV contrast and patients were treated with respiratory motion tracking in the CyberknifeTM system. Results: 30 patients (17 men and 13 women) with a median age of 67 years were included in the study. The median target volume was 41.29cc. The median prescription dose was 25Gy (24-36Gy) in a median of 5 fractions prescribed to a mean 78% isodose line. The median overall survival was 14 months. The 1 and 2 year local control was 78%. The worst toxicity included 3/30(10%) Grade III acute toxicity for pain, bleeding and vomiting. There was 2/30 (7%) Grade III long-term bowel obstructions. Conclusions: SBRT can be a useful and tolerable option for patients with recurrent pancreas cancer after prior radiation. PMID:26918041

  11. Stereotactic ablative radiotherapy for oligometastatic disease in liver.

    PubMed

    Kim, Myungsoo; Son, Seok Hyun; Won, Yong Kyun; Kay, Chul Seung

    2014-01-01

    Liver metastasis in solid tumors, including colorectal cancer, is the most frequent and lethal complication. The development of systemic therapy has led to prolonged survival. However, in selected patients with a finite number of discrete lesions in liver, defined as oligometastatic state, additional local therapies such as surgical resection, radiofrequency ablation, cryotherapy, and radiotherapy can lead to permanent local disease control and improve survival. Among these, an advance in radiation therapy made it possible to deliver high dose radiation to the tumor more accurately, without impairing the liver function. In recent years, the introduction of stereotactic ablative radiotherapy (SABR) has offered even more intensive tumor dose escalation in a few fractions with reduced dose to the adjacent normal liver. Many studies have shown that SABR for oligometastases is effective and safe, with local control rates widely ranging from 50% to 100% at one or two years. And actuarial survival at one and two years has been reported ranging from 72% to 94% and from 30% to 62%, respectively, without severe toxicities. In this paper, we described the definition and technical aspects of SABR, clinical outcomes including efficacy and toxicity, and related parameters after SABR in liver oligometastases from colorectal cancer. PMID:24868526

  12. Cranial stereotactic radiosurgery: current status of the initial paradigm shifter.

    PubMed

    Sheehan, Jason P; Yen, Chun-Po; Lee, Cheng-Chia; Loeffler, Jay S

    2014-09-10

    The concept of stereotactic radiosurgery (SRS) was first described by Lars Leksell in 1951. It was proposed as a noninvasive alternative to open neurosurgical approaches to manage a variety of conditions. In the following decades, SRS emerged as a unique discipline involving a collegial partnership among neurosurgeons, radiation oncologists, and medical physicists. SRS relies on the precisely guided delivery of high-dose ionizing radiation to an intracranial target. The focused convergence of multiple beams yields a potent therapeutic effect on the target and a steep dose fall-off to surrounding structures, thereby minimizing the risk of collateral damage. SRS is typically administered in a single session but can be given in as many as five sessions or fractions. By providing an ablative effect noninvasively, SRS has altered the treatment paradigms for benign and malignant intracranial tumors, functional disorders, and vascular malformations. Literature on extensive intracranial radiosurgery has unequivocally demonstrated the favorable benefit-to-risk profile that SRS affords for appropriately selected patients. In a departure from conventional radiotherapeutic strategies, radiosurgical principles have recently been extended to extracranial indications such as lung, spine, and liver tumors. The paradigm shift resulting from radiosurgery continues to alter the landscape of related fields. PMID:25113762

  13. [Stereotactic aspiration of Spirometra mansonides larvae].

    PubMed

    Caballero, Joel; Morales, Losmill; García, Diana; Alarcón, Idelmys; Torres, Anay; Sáez, Gladys

    2015-08-01

    Brain sparganosis is a non-common parasite infection by Diphyllobothrium or Spirometra mansonoides larvae. This last one is responsible for most of the infestations in humans. We report a 19 years male patient bearer of a brain sparganosis. The patient presented with headache and left hemiparesis. CT diagnosis of right thalamic lesions was made and aspiration biopsy was performed using stereotactic system, obtaining a whole and death larvae. Histopathology confirms a CNS parasitism and it was treated initially with albendazol. ELISA test confirmed Spirometra spp. infestation. The patient developed asymptomatic with total remission of the lesions. It constitutes the second report in Cuba of brain sparganosis. PMID:26436792

  14. Clinical accuracy of ExacTrac intracranial frameless stereotactic system

    SciTech Connect

    Ackerly, T.; Lancaster, C. M.; Geso, M.; Roxby, K. J.

    2011-09-15

    Purpose: In this paper, the authors assess the accuracy of the Brainlab ExacTrac system for frameless intracranial stereotactic treatments in clinical practice. Methods: They recorded couch angle and image fusion results (comprising lateral, longitudinal, and vertical shifts, and rotation corrections about these axes) for 109 stereotactic radiosurgery and 166 stereotactic radiotherapy patient treatments. Frameless stereotactic treatments involve iterative 6D image fusion corrections applied until the results conform to customizable pass criteria, theirs being 0.7 mm and 0.5 deg. for each axis. The planning CT slice thickness was 1.25 mm. It has been reported in the literature that the CT slices' thickness impacts the accuracy of localization to bony anatomy. The principle of invariance with respect to patient orientation was used to determine spatial accuracy. Results: The data for radiosurgery comprised 927 image pairs, of which 532 passed (pass ratio of 57.4%). The data for radiotherapy comprised 15983 image pairs, of which 10 050 passed (pass ratio of 62.9%). For stereotactic radiotherapy, the combined uncertainty of ExacTrac calibration, image fusion, and intrafraction motion was (95% confidence interval) 0.290-0.302 and 0.306-0.319 mm in the longitudinal and lateral axes, respectively. The combined uncertainty of image fusion and intrafraction motion in the anterior-posterior coordinates was 0.174-0.182 mm. For stereotactic radiosurgery, the equivalent ranges are 0.323-0.393, 0.337-0.409, and 0.231-0.281 mm. The overall spatial accuracy was 1.24 mm for stereotactic radiotherapy (SRT) and 1.35 mm for stereotactic radiosurgery (SRS). Conclusions: The ExacTrac intracranial frameless stereotactic system spatial accuracy is adequate for clinical practice, and with the same pass criteria, SRT is more accurate than SRS. They now use frameless stereotaxy exclusively at their center.

  15. Stereotactic radiosurgery of prostate cancer - dose distribution for VMAT and CyberKnife techniques

    NASA Astrophysics Data System (ADS)

    Ślosarek, Krzysztof; Osewski, Wojciech; Grządziel, Aleksandra; Stąpór-Fudzińska, Małgorzata; Szlag, Marta

    2016-06-01

    New capabilities of biomedical accelerators allow for very precise depositing of the radiation dose and imaging verification during the therapy. In addition, computer algorithms calculating dose distributions are taking into account the increasing number of physical effects. Therefore, administration of high dose fractionation, which is consistent with radiobiology used in oncology, becomes safer and safer. Stereotactic radiosurgery (SRS), which is very precise irradiation with high dose fractionation is increasingly widespread use in radiotherapy of prostate cancer. For this purpose different biomedical accelerators are used. The aim of this study is to compare dose distributions for two techniques: VMAT and CyberKnife. Statistical analysis was performed for the two groups of patients treated by VMAT technique (25 patients), and CyberKnife technique (15 patients). The analysis shows that the dose distributions are comparable, both in the treated area (prostate) and in the critical organs (rectum, urinary bladder, femoral heads). The results show that stereotactic radiosurgery of prostate cancer can be carried out on CyberKnife accelerator as well as on the classical accelerator with the use of VMAT technique.

  16. Stereotactic Ablative Body Radiation Therapy for Octogenarians With Non-Small Cell Lung Cancer

    SciTech Connect

    Takeda, Atsuya; Sanuki, Naoko; Eriguchi, Takahisa; Kaneko, Takeshi; Morita, Satoshi; Handa, Hiroshi; Aoki, Yousuke; Oku, Yohei; Kunieda, Etsuo

    2013-06-01

    Purpose: To retrospectively investigate treatment outcomes of stereotactic ablative body radiation therapy (SABR) for octogenarians with non-small cell lung cancer (NSCLC). Methods and Materials: Between 2005 and 2012, 109 patients aged ≥80 years with T1-2N0M0 NSCLC were treated with SABR: 47 patients had histology-unproven lung cancer; 62 patients had pathologically proven NSCLC. The prescribed doses were either 50 Gy/5 fractions for peripheral tumors or 40 Gy/5 fractions for centrally located tumors. The treatment outcomes, toxicities, and the correlating factors for overall survival (OS) were evaluated. Results: The median follow-up duration after SABR was 24.2 (range, 3.0-64.6) months. Only limited toxicities were observed, except for 1 grade 5 radiation pneumonitis. The 3-year local, regional, and distant metastasis-free survival rates were 82.3%, 90.1%, and 76.8%, respectively. The OS and lung cancer-specific survival rates were 53.7% and 70.8%, respectively. Multivariate analysis revealed that medically inoperable, low body mass index, high T stage, and high C-reactive protein were the predictors for short OS. The OS for the operable octogenarians was significantly better than that for inoperable (P<.01). Conclusions: Stereotactic ablative body radiation therapy for octogenarians was feasible, with excellent OS. Multivariate analysis revealed that operability was one of the predictors for OS. For medically operable octogenarians with early-stage NSCLC, SABR should be prospectively compared with resection.

  17. Stereotactic radiosurgery for WHO grade I meningiomas.

    PubMed

    Sheehan, Jason P; Williams, Brian J; Yen, Chun Po

    2010-09-01

    Meningiomas represent a common intracranial tumor in the adult population. Although extirpation to achieve a gross total resection or at least decrease mass effect has been the mainstay of treatment, stereotactic radiosurgery has come to play an increasingly important role in the management of patients with meningiomas. Radiosurgery utilizes highly focused, beams of ionizing radiation to inactivate tumor cells. Image guidance and a steep dose fall off are critical features of this approach. The radiobiology of radiosurgery differs in certain advantageous ways from conventional radiotherapy. Radiosurgery initially was utilized to treat recurrent or residual skull base meningiomas. As success was observed in this setting, radiosurgery has gradually expanded its role so as to treat convexity meningiomas; it is also used as an upfront treatment for patients for whom clinical and neuro-imaging findings are consistent with a meningioma. Most large series demonstrate tumor control rates for patients with grade I meningiomas in excess of 85%. Neurological function is generally preserved or improved for patients with meningiomas. However, complications can occur. Longitudinal follow-up including neurologic and radiologic assessment is required. Single and multisession stereotactic radiosurgery will likely play an expanded role in the treatment of patients with meningiomas. PMID:20734218

  18. Dual mode stereotactic localization method and application

    DOEpatents

    Keppel, Cynthia E.; Barbosa, Fernando Jorge; Majewski, Stanislaw

    2002-01-01

    The invention described herein combines the structural digital X-ray image provided by conventional stereotactic core biopsy instruments with the additional functional metabolic gamma imaging obtained with a dedicated compact gamma imaging mini-camera. Before the procedure, the patient is injected with an appropriate radiopharmaceutical. The radiopharmaceutical uptake distribution within the breast under compression in a conventional examination table expressed by the intensity of gamma emissions is obtained for comparison (co-registration) with the digital mammography (X-ray) image. This dual modality mode of operation greatly increases the functionality of existing stereotactic biopsy devices by yielding a much smaller number of false positives than would be produced using X-ray images alone. The ability to obtain both the X-ray mammographic image and the nuclear-based medicine gamma image using a single device is made possible largely through the use of a novel, small and movable gamma imaging camera that permits its incorporation into the same table or system as that currently utilized to obtain X-ray based mammographic images for localization of lesions.

  19. Stereotactic localization using magnetic resonance imaging.

    PubMed

    Walton, L; Hampshire, A; Forster, D M; Kemeny, A A

    1995-01-01

    A phantom study has been carried out to assess the accuracy of stereotactic localisation, using magnetic resonance imaging. The stereotactic coordinates of an array of Perspex rods within the phantom were determined and compared with measured values, in a series of transverse, coronal and sagittal images. In the transverse plane, the maximum errors experienced were X = 2.3 mm and Y = 10.7 mm. If the third fiducial plate, at the front of the frame, were not used in the scaling of the images, there was considerable improvement in the Y direction (maximum error Y = 2.1 mm). However, some deterioration in the accuracy in the X direction resulted, particularly at the extremes of Z (maximum error X = 3.5 mm). In the coronal plane, the maximum errors were X = 1.8 mm and Z = 8.0 mm. With the third plate off, the errors decreased to X = 1.9 mm and Z = 3.3 mm. In the sagittal plane, the maximum errors recorded were Y = 1.1 mm and Z = 7.5 mm. It is not possible to calibrate in this plane without the third plate. PMID:8584823

  20. Multimedia educational services in stereotactic radiotherapy.

    PubMed

    Bazioglou, M; Theodorou, K; Kappas, C

    1999-01-01

    The computer-based learning methods in medicine have been well established as stand-alone learning systems. Recently, these systems were enriched with the use of telematics technology to provide distance learning capabilities. Stereotactic radiotherapy is one of the most representative advanced radiotherapy techniques. Due to the multidisciplinary character of the technique and the rapid evolution of technology implemented, the demands in training have increased. The potential of interactive multimedia and Internet technologies for the achievement of distance learning capabilities in this domain are investigated. The realization of a computer-based educational program in stereotactic radiotherapy in a multimedia format is a new application in the computer-aided distance learning field. The system is built according to a client and server architecture, based on the Internet infrastructure, and composed of server nodes. The impact of the system may be described in terms of: time and transportation costs saving, flexibility in training (scheduling, rate and subject selection), online communication and interaction with experts, cost effective access to material (delivery or access by a large number of users and revision of the material by avoiding high costs of computer-based training systems and database development). PMID:10394345

  1. Survival after stereotactic biopsy of malignant gliomas

    SciTech Connect

    Coffey, R.J.; Lunsford, L.D.; Taylor, F.H.

    1988-03-01

    For many patients with malignant gliomas in inaccessible or functionally important locations, stereotactic biopsy followed by radiation therapy (RT) may be a more appropriate initial treatment than craniotomy and tumor resection. We studied the long term survival in 91 consecutive patients with malignant gliomas diagnosed by stereotactic biopsy: 64 had glioblastoma multiforme (GBM) and 27 had anaplastic astrocytoma (AA). Sixty-four per cent of the GBMs and 33% of the AAs involved deep or midline cerebral structures. The treatment prescribed after biopsy, the tumor location, the histological findings, and the patient's age at presentation (for AAs) were statistically important factors determining patient survival. If adequate RT (tumor dose of 5000 to 6000 cGy) was not prescribed, the median survival was less than or equal to 11 weeks regardless of tumor histology or location. The median survival for patients with deep or midline tumors who completed RT was similar in AA (19.4 weeks) and GBM (27 weeks) cases. Histology was an important predictor of survival only for patients with adequately treated lobar tumors. The median survival in lobar GBM patients who completed RT was 46.9 weeks, and that in lobar AA patients who completed RT was 129 weeks. Cytoreductive surgery had no statistically significant effect on survival. Among the clinical factors examined, age of less than 40 years at presentation was associated with prolonged survival only in AA patients. Constellations of clinical features, tumor location, histological diagnosis, and treatment prescribed were related to survival time.

  2. Stereotactic Body Radiation Therapy in Recurrent Hepatocellular Carcinoma

    SciTech Connect

    Huang, Wen-Yen; Jen, Yee-Min; Lee, Meei-Shyuan; Chang, Li-Ping; Chen, Chang-Ming; Ko, Kai-Hsiung; Lin, Kuen-Tze; Lin, Jang-Chun; Chao, Hsing-Lung; Lin, Chun-Shu; Su, Yu-Fu; Fan, Chao-Yueh; Chang, Yao-Wen

    2012-10-01

    Purpose: To examine the safety and efficacy of Cyberknife stereotactic body radiation therapy (SBRT) and its effect on survival in patients of recurrent hepatocellular carcinoma (HCC). Methods and Materials: This was a matched-pair study. From January 2008 to December 2009, 36 patients with 42 lesions of unresectable recurrent HCC were treated with SBRT. The median prescribed dose was 37 Gy (range, 25 to 48 Gy) in 4-5 fractions over 4-5 consecutive working days. Another 138 patients in the historical control group given other or no treatments were selected for matched analyses. Results: The median follow-up time was 14 months for all patients and 20 months for those alive. The 1- and 2-year in-field failure-free rates were 87.6% and 75.1%, respectively. Out-field intrahepatic recurrence was the main cause of failure. The 2-year overall survival (OS) rate was 64.0%, and median time to progression was 8.0 months. In the multivariable analysis of all 174 patients, SBRT (yes vs. no), tumor size ({<=}4 cm vs. >4 cm), recurrent stage (stage IIIB/IV vs. I) and Child-Pugh classification (A vs. B/C) were independent prognostic factors for OS. Matched-pair analysis revealed that patients undergoing SBRT had better OS (2-year OS of 72.6% vs. 42.1%, respectively, p = 0.013). Acute toxicities were mild and tolerable. Conclusion: SBRT is a safe and efficacious modality and appears to be well-tolerated at the dose fractionation we have used, and its use correlates with improved survival in this cohort of patients with recurrent unresectable HCC. Out-field recurrence is the major cause of failure. Further studies of combinations of SBRT and systemic therapies may be reasonable.

  3. Hypofractionated stereotactic radiation therapy in skull base meningiomas.

    PubMed

    Navarria, Pierina; Pessina, Federico; Cozzi, Luca; Clerici, Elena; Villa, Elisa; Ascolese, Anna Maria; De Rose, Fiorenza; Comito, Tiziana; Franzese, Ciro; D'Agostino, Giuseppe; Lobefalo, Francesca; Fogliata, Antonella; Reggiori, Giacomo; Fornari, Maurizio; Tomatis, Stefano; Bello, Lorenzo; Scorsetti, Marta

    2015-09-01

    To investigate the role of hypo-fractionated stereotactic radiation treatment (HSRT) in the management of skull base meningioma. Twenty-six patients were included in the study and treated with a dose of 30 Gy in 5 fractions with volumetric modulated arc therapy (RapidArc). Eighteen patients were symptomatic before treatment. Endpoints were local toxicity and relief from symptoms. Tumors were located in anterior skull base in 4/27 cases, in middle skull base in 12/27 and in posterior skull base in 11/27. HSRT was performed as first treatment in 17 (65 %) patients, in 9 (35 %) patients it followed a previous partial resection. Median follow up was 24.5 months (range 5-57 months). clinical remission of symptoms, complete or partial, was obtained in the vast majority of patients after treatment. Out of the 18 symptomatic patients, partial remission occurred in 9 (50 %) patients and complete remission in 9 (50 %). All asymptomatic patients retained their status after treatment. No severe neurologic toxicity grade III-IV was recorded. No increase of meningioma in the same site of treatment occurred; 16 (62 %) patients had stable disease and 9 (38 %) patients had tumor reduction. The mean tumor volume after treatment was 10.8 ± 17.8 cm(3) compared with 13.0 ± 19.1 cm(3) before treatment (p = 0.02). The mean actuarial OS was 54.4 ± 2.8 months. The 1- and 2-years OS was 92.9 ± 0.7 %. HSRT proved to be feasible for these patients not eligible to full surgery or to ablative radiation therapy. Local control and durability of results suggest for a routine application of this approach in properly selected cases. PMID:26040487

  4. Frameless stereotactic body radiation therapy for multiple lung metastases.

    PubMed

    Li, Qilin; Mu, Jinming; Gu, Wendong; Chen, Yuan; Ning, Zhonghua; Jin, Jianxue; Pei, Honglei

    2014-01-01

    Two patients with multiple lung metastases (≥ 5) were treated using frameless stereotactic body radiation therapy (SBRT) on an Elekta Axesse linear accelerator equipped with an interdigitation-capable multileaf collimator and four-dimensional cone-beam CT (4D CBCT). The technique and the early clinical outcomes were evaluated. Patient A with five lung metastases and Patient B with seven lung metastases underwent SBRT (48 Gy/8 fractions for Patient A, 42 Gy/7 fractions for Patient B). The treatments were administered using a 6 MV photon beam. The nominal dose rate was 660 MUs/min. Patients were positioned and immobilized using thermoplastic masks and image guidance was done using 4D CBCT. The targets were delineated on the images of the 4D CT, and the positron emission tomography-computed tomography (PET-CT) images were taken as references. A two-step, volumetric-modulated arc therapy (VMAT) plan was designed for each patient. Step 1: the lesions in one lung were irradiated by a 210° arc field; Step 2: the rest of the lesions in the other lung were irradiated by a 120° arc field. Plans were evaluated using conformity index (CI) and homogeneity index (HI). Patients were followed up and adverse events were graded according to the Common Terminology Criteria for Adverse Events v4.0 (CTCAE v4.0). The beam-on time of each treatment was less than 10 min. The CI and HI for the two plans were 0.562, 0.0709 and 0.513, 0.0794, respectively. Pulmonary function deteriorated slightly in both patients, and the patient with seven lung lesions was confirmed to have Grade 1 radiation pneumonitis. The technique was fast, accurate, and well tolerated by patients, and the two-step plan is a helpful design in reducing the dose to the lungs. PMID:25207400

  5. Stereotactic Radiosurgery for Acoustic Neuromas: What Happens Long Term?

    SciTech Connect

    Roos, Daniel E.; Potter, Andrew E.; Brophy, Brian P.

    2012-03-15

    Purpose: To determine the clinical outcomes for acoustic neuroma treated with low-dose linear accelerator stereotactic radiosurgery (SRS) >10 years earlier at the Royal Adelaide Hospital using data collected prospectively at a dedicated SRS clinic. Methods and Materials: Between November 1993 and December 2000, 51 patients underwent SRS for acoustic neuroma. For the 44 patients with primary SRS for sporadic (unilateral) lesions, the median age was 63 years, the median of the maximal tumor diameter was 21 mm (range, 11-34), and the marginal dose was 14 Gy for the first 4 patients and 12 Gy for the other 40. Results: The crude tumor control rate was 97.7% (1 patient required salvage surgery for progression at 9.75 years). Only 8 (29%) of 28 patients ultimately retained useful hearing (interaural pure tone average {<=}50 dB). Also, although the Kaplan-Meier estimated rate of hearing preservation at 5 years was 57% (95% confidence interval, 38-74%), this decreased to 24% (95% confidence interval, 11-44%) at 10 years. New or worsened V and VII cranial neuropathy occurred in 11% and 2% of patients, respectively; all cases were transient. No case of radiation oncogenesis developed. Conclusions: The long-term follow-up data of low-dose (12-14 Gy) linear accelerator SRS for acoustic neuroma have confirmed excellent tumor control and acceptable cranial neuropathy rates but a continual decrease in hearing preservation out to {>=}10 years.

  6. Pulmonary imaging after stereotactic radiotherapy-does RECIST still apply?

    PubMed

    Mattonen, Sarah A; Ward, Aaron D; Palma, David A

    2016-09-01

    The use of stereotactic ablative radiotherapy (SABR) for the treatment of primary lung cancer and metastatic disease is rapidly increasing. However, the presence of benign fibrotic changes on CT imaging makes response assessment following SABR a challenge, as these changes develop with an appearance similar to tumour recurrence. Misclassification of benign fibrosis as local recurrence has resulted in unnecessary interventions, including biopsy and surgical resection. Response evaluation criteria in solid tumours (RECIST) are widely used as a universal set of guidelines to assess tumour response following treatment. However, in the context of non-spherical and irregular post-SABR fibrotic changes, the RECIST criteria can have several limitations. Positron emission tomography can also play a role in response assessment following SABR; however, false-positive results in regions of inflammatory lung post-SABR can be a major clinical issue and optimal standardized uptake values to distinguish fibrosis and recurrence have not been determined. Although validated CT high-risk features show a high sensitivity and specificity for predicting recurrence, most recurrences are not detected until more than 1-year post-treatment. Advanced quantitative radiomic analysis on CT imaging has demonstrated promise in distinguishing benign fibrotic changes from local recurrence at earlier time points, and more accurately, than physician assessment. Overall, the use of RECIST alone may prove inferior to novel metrics of assessing response. PMID:27245137

  7. Stereotactic radiosurgery for intracranial arteriovenous malformations: A review.

    PubMed

    Moorthy, Ranjith K; Rajshekhar, Vedantam

    2015-01-01

    Stereotactic radiosurgery (SRS) has proven to be an effective strategy in the management of intracranial arteriovenous malformations (AVMs) in children and adults over the past three decades. Its application has resulted in lowering the morbidity and mortality associated with treatment of deep-seated AVMs. SRS has been used as a primary modality of therapy as well as in conjunction with embolization and microsurgery in the management of AVMs. The obliteration rate after SRS has been reported to range from 35% to 92%. Smaller AVMs receiving higher marginal doses have obliteration rates of 70% and more. The median follow-up reported in most series is approximately 36-40 months. The median time to obliteration has been reported to be approximately 24-36 months in most series. Radiation-induced neurological complications have been reported in less than 10% of patients, with a 1.5%-6% risk of developing a new permanent neurological deficit. The bleeding rate during the latency to obliteration has been reported to be approximately 5%. This review describes the experience reported in literature with respect to the indications, dosage, factors affecting obliteration rate of AVMs, and complications after SRS. PMID:26588616

  8. Effect of radiation protraction on BED in the case of large fraction dose

    SciTech Connect

    Kuperman, V. Y.

    2013-08-15

    Purpose: To investigate the effect of radiation protraction on biologically effective dose (BED) in the case when dose per fraction is significantly greater than the standard dose of 2 Gy.Methods: By using the modified linear-quadratic model with monoexponential repair, the authors investigate the effect of long treatment times combined with dose escalation.Results: The dependences of the protraction factor and the corresponding BED on fraction time were determined for different doses per fraction typical for stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT). In the calculations, the authors consider changes in the BED to the normal tissue under the condition of fixed BED to the target.Conclusion: The obtained results demonstrate that simultaneous increase in fraction time and dose per fraction can be beneficial for SRS and SBRT because of the related decrease in BED to normal structures while BED to the target is fixed.

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

    PubMed

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

    2010-01-01

    Aim of this study is to assess the role of stereotactic radiosurgery (SRS) and radiotherapy (SRT) in management of cranial nerves schwannomas by analysis of tumor control, clinical response and variables affecting treatment outcomes. Between April 2005 and January 2009 patients with schwannomas of VIII (63), V (14) and caudal nerves (2) were treated in Burdenko Moscow Neurosurgical Institute using linear accelerator. Mean age was 49 years (13-82). In 42 cases radiation treatment was preceded by surgical resection. 13 patients had type I or II neurofibromatosis. Mean volume of the tumor was 3.9 cm3 (0.5-14.4 cm3) and 13.4 cm3 (2.8-41.3 cm3) for SRS and SRT, respectively. Mean SRS dose was 12 Gy (10.8-14.4 Gy) for vestibular schwannomas and 15 Gy (13.2-18 Gy) for schwannomas of other nerves. In hypofractionated SRT the dose of 35 Gy was delivered in 7 fractions or 30 Gy in 6 fractions. In cases of classical fractioning total dose of 50-60 Gy was divided into daily fractions of 1.8-2.0 Gy. Radiographic tumor control rate reached 97.5% at the last follow-up. 5 patients experienced trigeminal dysfunction, it was transient in 3 cases and persistent in 2. Permanent decline in House-Brackmann facial nerve scale developed in 2 of 79 patients. After treatment effective hearing (class I-II) was preserved in 7 of 9 patients (67%) who had same level of hearing before SRS. Linear accelerator-based stereotactic radiation treatment provides long-term tumor control associated with high rates of preservation of neurological functions. No further tumor surgery was necessary in 100% of cases with solitary tumors with a minimal follow-up of 5 years. PMID:20429361

  10. Robotic Stereotactic Radioablation Concomitant With Neo-Adjuvant Chemotherapy for Breast Tumors

    SciTech Connect

    Bondiau, Pierre-Yves; Bahadoran, Phillipe; Lallement, Michel; Birtwisle-Peyrottes, Isabelle; Chapellier, Claire; Chamorey, Emmanuel; Courdi, Adel; Quielle-Roussel, Catherine; Thariat, Juliette; Ferrero, Jean-Marc

    2009-11-15

    Purpose: Robotic stereotactic radioablation (RSR) allows stereotactic irradiation of thoracic tumors; however, it has never been used for breast tumors and may have a real potential. We conducted a Phase I study, including neoadjuvant chemotherapy (NACT), a two-level dose-escalation study (6.5 Gy x 3 fractions and 7.5 Gy x 3 fractions) using RSR and breast-conserving surgery followed by conventional radiotherapy. Materials and Methods: To define toxicity, we performed a dermatologic exam (DE) including clinical examination by two independent observers and technical examination by colorimetry, dermoscopy, and skin ultrasound. DE was performed before NACT (DE0), at 36 days (DE1), at 56 days (DE2), after the NACT treatment onset, and before surgery (DE3). Surgery was performed 4-8 weeks after the last chemotherapy session. A pathologic examination was also performed. Results: There were two clinical complete responses and four clinical partial responses at D56 and D85. Maximum tolerable dose was not reached. All patients tolerated RSR with no fatigue; 2 patients presented with mild pain after the third fraction of the treatment. There was no significant toxicity measured with ultrasound and dermoscopy tests. Postoperative irradiation (50 Gy) has been delivered without toxicity. Conclusion: The study showed the feasibility of irradiation with RSR combined with chemotherapy and surgery for breast tumors. There was no skin toxicity at a dose of 19.5 Gy or 22.5 Gy delivered in three fractions combined with chemotherapy. Lack of toxicity suggested that the dose could be increased further. Pathologic response was acceptable.

  11. Stereotactic Body Radiotherapy and Ablative Therapies for Lung Cancer.

    PubMed

    Abbas, Ghulam; Danish, Adnan; Krasna, Mark J

    2016-07-01

    The treatment paradigm for early stage lung cancer and oligometastatic disease to the lung is rapidly changing. Ablative therapies, especially stereotactic body radiation therapy, are challenging the surgical gold standard and have the potential to be the standard for operable patients with early stage lung cancer who are high risk due to co- morbidities. The most commonly used ablative modalities include stereotactic body radiation therapy, microwave ablation, and radiofrequency ablation. PMID:27261915

  12. Intrafractional setup errors in patients undergoing non-invasive fixation using an immobilization system during hypofractionated stereotactic radiotherapy for lung tumors

    PubMed Central

    Watanabe, Meguru; Onishi, Hiroshi; Kuriyama, Kengo; Komiyama, Takafumi; Marino, Kan; Araya, Masayuki; Saito, Ryo; Aoki, Shinichi; Maehata, Yoshiyasu; Tominaga, Rihito; Oguri, Jitsuhiko; Sano, Naoki; Araki, Tsutomu

    2013-01-01

    Intrafractional setup errors during hypofractionated stereotactic radiotherapy (SRT) were investigated on the patient under voluntary breath-holding conditions with non-invasive immobilization on the CT-linac treatment table. A total of 30 patients with primary and metastatic lung tumors were treated with the hypofractionated SRT with a total dose of 48–60 Gy with four treatment fractions. The patient was placed supine and stabilized on the table with non-invasive patient fixation. Intrafractional setup errors in Right/Left (R.L.), Posterior/Anterior (P.A.), and Inferior/Superior (I.S.) dimensions were analyzed with pre- and post-irradiation CT images. The means and one standard deviation of the intrafractional errors were 0.9 ± 0.7mm (R.L.), 0.9 ± 0.7mm (P.A.) and 0.5 ± 1.0 mm (I.S.). Setup errors in each session of the treatment demonstrated no statistically significant difference in the mean value between any two sessions. The frequency within 3mm displacement was 98% in R.L., 98% in P.A. and 97% in I.S. directions. SRT under the non-invasive patient fixation immobilization system with a comparatively loose vacuum pillow demonstrated satisfactory reproducibility of minimal setup errors with voluntary breath-holding conditions that required a small internal margin. PMID:23412467

  13. Possible Misinterpretation of Demarcated Solid Patterns of Radiation Fibrosis on CT Scans as Tumor Recurrence in Patients Receiving Hypofractionated Stereotactic Radiotherapy for Lung Cancer

    SciTech Connect

    Takeda, Atsuya; Kunieda, Etsuo Takeda, Toshiaki; Tanaka, Michio; Sanuki, Naoko; Fujii, Hirofumi; Shigematsu, Naoyuki; Kubo, Atsushi M.D.

    2008-03-15

    Purpose: To retrospectively analyze opacity changes near primary lung cancer tumors irradiated by using hypofractionated stereotactic radiotherapy (HSRT) to determine the presence or absence of tumor recurrence. Methods and Materials: After review-board approval for a retrospective study, we examined data from 50 patients treated with curative intent for proven or highly suspected localized peripheral-lung cancer and followed up for at least 12 months. All patients had received 50 Gy in five fractions (80% isodose) and were followed up monthly with chest X-ray until clinical and X-ray findings stabilized. Follow-up computed tomography scans were performed 1 and 3 months after HSRT and thereafter at 3-month intervals during the first 2 years. Results: Median follow-up was 30.4 months (range, 12.0-73.8 months). Abnormal opacities that were suspicious for recurrent tumor appeared in 20 patients at a median of 20.7 months (range, 5.9-61.4 months). Only 3 patients were finally found to have recurrence; 14 were recurrence free but were suspected to have fibrosis, and findings for the other 3 patients were considered equivocal because of a short follow-up period ({<=}6 months). Conclusion: Radiation fibrosis, which may occur 1 year or longer after completion of HSRT, is difficult to distinguish from tumor recurrence. Even when opacities increase on follow-up radiologic scans, recurrence cannot be diagnosed conclusively based on image findings; biopsy occasionally is warranted.

  14. Integration of Functional MRI and White Matter Tractography in Stereotactic Radiosurgery Clinical Practice

    SciTech Connect

    Pantelis, Evaggelos; Papadakis, Nikolaos; Verigos, Kosmas; Stathochristopoulou, Irene; Antypas, Christos; Lekas, Leonidas; Tzouras, Argyrios; Georgiou, Evangelos; Salvaras, Nikolaos

    2010-09-01

    Purpose: To study the efficacy of the integration of functional magnetic resonance imaging (fMRI) and diffusion tensor imaging tractography data into stereotactic radiosurgery clinical practice. Methods and Materials: fMRI and tractography data sets were acquired and fused with corresponding anatomical MR and computed tomography images of patients with arteriovenous malformation (AVM), astrocytoma, brain metastasis, or hemangioma and referred for stereotactic radiosurgery. The acquired data sets were imported into a CyberKnife stereotactic radiosurgery system and used to delineate the target, organs at risk, and nearby functional structures and fiber tracts. Treatment plans with and without the incorporation of the functional structures and the fiber tracts into the optimization process were developed and compared. Results: The nearby functional structures and fiber tracts could receive doses of >50% of the maximum dose if they were excluded from the planning process. In the AVM case, the doses received by the Broadmann-17 structure and the optic tract were reduced to 700 cGy from 1,400 cGy and to 1,200 cGy from 2,000 cGy, respectively, upon inclusion into the optimization process. In the metastasis case, the motor cortex received 850 cGy instead of 1,400 cGy; and in the hemangioma case, the pyramidal tracts received 780 cGy instead of 990 cGy. In the astrocytoma case, the dose to the motor cortex bordering the lesion was reduced to 1,900 cGy from 2,100 cGy, and therefore, the biologically equivalent dose in three fractions was delivered instead. Conclusions: Functional structures and fiber tracts could receive high doses if they were not considered during treatment planning. With the aid of fMRI and tractography images, they can be delineated and spared.

  15. Intensity-modulated stereotactic radiotherapy (IMSRT) for skull-base meningiomas

    SciTech Connect

    Yenice, Kamil M. . E-mail: kyenice@radonc.uchicago.edu; Narayana, Ashwatha; Chang, Jenghwa; Gutin, Philip H.; Amols, Howard I.

    2006-11-15

    Purpose: To investigate the potential benefits of a micromultileaf collimator ({mu}MLC) -based intensity-modulated stereotactic radiotherapy (IMSRT) in skull-base meningiomas. Methods and Materials: Seven patients with inoperable or recurrent small-volume (1.7-15.5 cc) skull-base meningiomas were treated with IMSRT to 54 Gy in 30 fractions using a {mu}MLC in the dynamic mode. IMSRT plan quality was evaluated in comparison with the conformal stereotactic radiotherapy technique, using the same beam arrangement and static delivery with the {mu}MLC. Plans were compared using multiple dose distributions and dose-volume histograms for the planning target volume and organs at risk. The conformity and uniformity metrics, as well as normal-tissue complication probabilities, were calculated for the two techniques. Follow-up with MRI and clinical examination was performed at regular intervals. Results: With a mean follow-up of 17 months, local control has been achieved in all cases, and no treatment-related toxicities have been noted. For cavernous sinus tumors overlapping with optic apparatus, IMSRT has improved the dose uniformity within the target on average by 8%, which resulted in a reduction of the estimated chiasm normal-tissue complication probability by up to 65%. Conclusions: Intensity-modulated stereotactic radiotherapy can be safely delivered to improve the dose distributions in select skull-base meningiomas with an appreciable concomitant dose reduction to involved critical structures. Longer follow-up with a larger patient group is necessary to demonstrate sustained tumor control and low morbidity with IMSRT for small inoperable, recurrent, or subtotally resected meningiomas.

  16. Increased Bowel Toxicity in Patients Treated With a Vascular Endothelial Growth Factor Inhibitor (VEGFI) After Stereotactic Body Radiation Therapy (SBRT)

    SciTech Connect

    Barney, Brandon M.; Markovic, Svetomir N.; Laack, Nadia N.; Miller, Robert C.; Sarkaria, Jann N.; Macdonald, O. Kenneth; Bauer, Heather J.; Olivier, Kenneth R.

    2013-09-01

    Purpose: Gastrointestinal injury occurs rarely with agents that affect the vascular endothelial growth factor receptor and with abdominal stereotactic body radiation therapy (SBRT). We explored the incidence of serious bowel injury (SBI) in patients treated with SBRT with or without vascular endothelial growth factor inhibitor (VEGFI) therapy. Methods and Materials: Seventy-six patients with 84 primary or metastatic intra-abdominal lesions underwent SBRT (median dose, 50 Gy in 5 fractions). Of the patients, 20 (26%) received VEGFI within 2 years after SBRT (bevacizumab, n=14; sorafenib, n=4; pazopanib, n=1; sunitinib, n=1). The incidence of SBI (Common Terminology Criteria for Adverse Events, version 4.0, grade 3-5 ulceration or perforation) after SBRT was obtained, and the relationship between SBI and VEGFI was examined. Results: In the combined population, 7 patients (9%) had SBI at a median of 4.6 months (range, 3-17 months) from SBRT. All 7 had received VEGFI before SBI and within 13 months of completing SBRT, and 5 received VEGFI within 3 months of SBRT. The 6-month estimate of SBI in the 26 patients receiving VEGFI within 3 months of SBRT was 38%. No SBIs were noted in the 63 patients not receiving VEGFI. The log–rank test showed a significant correlation between SBI and VEGFI within 3 months of SBRT (P=.0006) but not between SBI and radiation therapy bowel dose (P=.20). Conclusions: The combination of SBRT and VEGFI results in a higher risk of SBI than would be expected with either treatment independently. Local therapies other than SBRT may be considered if a patient is likely to receive a VEGFI in the near future.

  17. Hypofractionated stereotactic radiotherapy and continuous low-dose temozolomide in patients with recurrent or progressive malignant gliomas.

    PubMed

    Minniti, Giuseppe; Scaringi, Claudia; De Sanctis, Vitaliana; Lanzetta, Gaetano; Falco, Teresa; Di Stefano, Domenica; Esposito, Vincenzo; Enrici, Riccardo Maurizi

    2013-01-01

    To evaluate the efficacy of reirradiation and systemic chemotherapy as salvage treatment in patients with recurrent malignant glioma. Between May 2006 and December 2011, 54 patients with recurrent malignant glioma received hypofractionated stereotactic radiotherapy (HSRT) plus systemic therapy at University of Rome Sapienza, Sant' Andrea Hospital. All patients had Karnofsky performance score ≥60 and were previously treated with standard conformal RT (60 Gy) with concomitant and adjuvant temozolomide (TMZ) up to 12 cycles. Thirty-eight patients had a GBM and 16 patients had a grade 3 glioma. The median time interval between primary RT and reirradiation was 15.5 months. At the time of recurrence all patients received HSRT (30 Gy in 6-Gy fractions) plus concomitant TMZ (75 mg/m(2)/day) followed by continuous TMZ at 50 mg/m(2) everyday up to 1 year or until progression. Median overall survival after HSRT was 12.4 months, and the 12- and 24-month survival rates were 53 and 16 %, respectively. The median progression-free survival (PFS) was 6 months, and the 12- and 24-month PFS rates were 24 and 10 %, respectively. KPS >70 (P = 0.04) and grade 3 glioma were independent favourable prognostic factors for survival. In general chemoradiation regimen was well tolerated with relatively low treatment-related toxicity. HSRT plus concomitant TMZ followed by continuous dose-intense TMZ is a feasible treatment option associated with survival benefits and low risk of complications in selected patients with recurrent malignant glioma. The potential advantages of combined chemoradiation schedules in patients with recurrent malignant gliomas need to be explored in future studies. PMID:23129347

  18. Image-guided robotic stereotactic body radiotherapy for benign spinal tumors: theUniversity of California San Francisco preliminary experience.

    PubMed

    Sahgal, A; Chou, D; Ames, C; Ma, L; Lamborn, K; Huang, K; Chuang, C; Aiken, A; Petti, P; Weinstein, P; Larson, D

    2007-12-01

    We evaluate our preliminary experience using the Cyberknife Radiosurgery System in treating benign spinal tumors. A retrospective review of 16 consecutively treated patients, comprising 19 benign spinal tumors, was performed. Histologic types included neurofibroma [11], chordoma [4], hemangioma [2], and meningioma [2]. Three patients had Neurofibromatosis Type 1 (NF1). Only one tumor, recurrent chordoma, had been previously irradiated, and as such not considered in the local failure analysis. Local failure, for the remaining 18 tumors, was based clinically on symptom progression and/or tumor enlargement based on imaging. Indications for spine stereotactic body radiotherapy (SBRT) consisted of either adjuvant to subtotal resection (5/19), primary treatment alone (12/19), boost following external beam radiotherapy (1/19), and salvage following previous radiation (1/19). Median tumor follow-up is 25 months (2-37), and one patient (with NF1) died at 12 months from a stroke. The median total dose, number of fractions, and prescription isodose was 21 Gy (10-30 Gy), 3 fx (1-5 fx), 80% (42-87%). The median tumor volume was 7.6 cc (0.2-274.1 cc). The median V100 (volume V receiving 100% of the prescribed dose) and maximum tumor dose was 95% (77-100%) and 26.7 Gy (15.4-59.7 Gy), respectively. Three tumors progressed at 2, 4, and 36 months post-SR (n=18). Two tumors were neurofibromas (both in NF1 patients), and the third was an intramedullary hemangioblastoma. Based on imaging, two tumors had MRI documented progression, three had regressed, and 13 were unchanged (n=18). With short follow-up, local control following Cyberknife spine SBRT for benign spinal tumors appear acceptable. PMID:17994789

  19. High-dose MVCT image guidance for stereotactic body radiation therapy

    SciTech Connect

    Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D.; Chao, Edward; Lucas, Dan; Flynn, Ryan T.; Miften, Moyed

    2012-08-15

    Purpose: Stereotactic body radiation therapy (SBRT) is a potent treatment for early stage primary and limited metastatic disease. Accurate tumor localization is essential to administer SBRT safely and effectively. Tomotherapy combines helical IMRT with onboard megavoltage CT (MVCT) imaging and is well suited for SBRT; however, MVCT results in reduced soft tissue contrast and increased image noise compared with kilovoltage CT. The goal of this work was to investigate the use of increased imaging doses on a clinical tomotherapy machine to improve image quality for SBRT image guidance. Methods: Two nonstandard, high-dose imaging modes were created on a tomotherapy machine by increasing the linear accelerator (LINAC) pulse rate from the nominal setting of 80 Hz, to 160 Hz and 300 Hz, respectively. Weighted CT dose indexes (wCTDIs) were measured for the standard, medium, and high-dose modes in a 30 cm solid water phantom using a calibrated A1SL ion chamber. Image quality was assessed from scans of a customized image quality phantom. Metrics evaluated include: contrast-to-noise ratios (CNRs), high-contrast spatial resolution, image uniformity, and percent image noise. In addition, two patients receiving SBRT were localized using high-dose MVCT scans. Raw detector data collected after each scan were used to reconstruct standard-dose images for comparison. Results: MVCT scans acquired using a pitch of 1.0 resulted in wCTDI values of 2.2, 4.7, and 8.5 cGy for the standard, medium, and high-dose modes respectively. CNR values for both low and high-contrast materials were found to increase with the square root of dose. Axial high-contrast spatial resolution was comparable for all imaging modes at 0.5 lp/mm. Image uniformity was improved and percent noise decreased as the imaging dose increased. Similar improvements in image quality were observed in patient images, with decreases in image noise being the most notable. Conclusions: High-dose imaging modes are made possible on a

  20. Stereotactic body radiotherapy for prostate cancer.

    PubMed

    Henderson, D R; Tree, A C; van As, N J

    2015-05-01

    The use of stereotactic body radiotherapy (SBRT) for localised prostate cancer is now supported by a substantial body of non-randomised data, with medium-term outcomes consistent with current standard radiotherapy. The ability to deliver profoundly hypofractionated treatment, combined with the relatively low α/β ratio of prostate cancer, may result in a more favourable therapeutic ratio, presenting an opportunity for isotoxic dose escalation. Furthermore, as treatment can be given in five attendances, SBRT has the potential both to reduce costs and improve patient quality of life. However, in a treatment landscape with many competing options of broadly similar efficacy, randomised trials are essential to define the relative benefits of this approach. SBRT also has an emerging application in oligometastatic prostate cancer, with promising early outcomes for delaying disease progression and deferring the need for androgen deprivation therapy. PMID:25707911

  1. 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.

  2. Stereotactic Body Radiation Therapy for Locally Advanced and Borderline Resectable Pancreatic Cancer Is Effective and Well Tolerated

    SciTech Connect

    Chuong, Michael D.; Springett, Gregory M.; Freilich, Jessica M.; Park, Catherine K.; Weber, Jill M.; Mellon, Eric A.; Hodul, Pamela J.; Malafa, Mokenge P.; Meredith, Kenneth L.; Hoffe, Sarah E.; Shridhar, Ravi

    2013-07-01

    Purpose: Stereotactic body radiation therapy (SBRT) provides high rates of local control (LC) and margin-negative (R0) resections for locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC), respectively, with minimal toxicity. Methods and Materials: A single-institution retrospective review was performed for patients with nonmetastatic pancreatic cancer treated with induction chemotherapy followed by SBRT. SBRT was delivered over 5 consecutive fractions using a dose painting technique including 7-10 Gy/fraction to the region of vessel abutment or encasement and 5-6 Gy/fraction to the remainder of the tumor. Restaging scans were performed at 4 weeks, and resectable patients were considered for resection. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Results: Seventy-three patients were evaluated, with a median follow-up time of 10.5 months. Median doses of 35 Gy and 25 Gy were delivered to the region of vessel involvement and the remainder of the tumor, respectively. Thirty-two BRPC patients (56.1%) underwent surgery, with 31 undergoing an R0 resection (96.9%). The median OS, 1-year OS, median PFS, and 1-year PFS for BRPC versus LAPC patients was 16.4 months versus 15 months, 72.2% versus 68.1%, 9.7 versus 9.8 months, and 42.8% versus 41%, respectively (all P>.10). BRPC patients who underwent R0 resection had improved median OS (19.3 vs 12.3 months; P=.03), 1-year OS (84.2% vs 58.3%; P=.03), and 1-year PFS (56.5% vs 25.0%; P<.0001), respectively, compared with all nonsurgical patients. The 1-year LC in nonsurgical patients was 81%. We did not observe acute grade ≥3 toxicity, and late grade ≥3 toxicity was minimal (5.3%). Conclusions: SBRT safely facilitates margin-negative resection in patients with BRPC pancreatic cancer while maintaining a high rate of LC in unresectable patients. These data support the expanded implementation of SBRT for pancreatic cancer.

  3. Stereotactic Interstitial Radiosurgery With the Photon Radiosurgery System (PRS) for Metastatic Brain Tumors: A Prospective Single-Center Clinical Trial

    SciTech Connect

    Pantazis, Georgios; Trippel, Michael; Birg, Walter; Ostertag, Christoph B.; Nikkhah, Guido

    2009-12-01

    Purpose: To evaluate the efficacy and the treatment outcome of tumor patients being treated stereotactically with a miniature X-ray generator (Photon Radiosurgery System, PRS). Methods and Materials: Thirty-five patients with histologically diagnosed cerebral metastases were treated with a single fraction of stereotactic interstitial irradiation (median, 18 Gy). Clinical and neuroimaging evaluation were assessed at 2-, 6-, and 12-week intervals postoperatively and every 3 months thereafter. Survival, local control, and distant and overall brain freedom from progression were obtained using the Kaplan-Meier method. Results: Median survival was 7.37 months and the actuarial survival rates at 6 and 12 months were 60.0% and 34.3%, respectively. Acute complications on six patients were associated with shorter survival. Local tumor control at the initial stage and at the last follow-up were 82% and 50%. Eighteen patients (53%) developed distant brain metastases after treatment. At 1 year, the local control rate and distant and overall brain freedom from progression were 33.0%, 43.3%, and 14.7%, respectively. A shorter local tumor control was observed by PRS treatment of a recurrent tumor and by irregular tumor configuration. Conclusions: Interstitial radiosurgery with the PRS requires continued investigation. It allows for an immediate and potentially cost-efficient treatment for patients with singular, small (<= 6.36 cm{sup 3}; or <= 2.3 cm) spherical brain metastasis subsequent to a stereotactic biopsy.

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

    SciTech Connect

    Wurm, Reinhard E. . E-mail: Reinhard.Wurm@charite.de; Kuczer, David A.; Schlenger, Lorenz; Matnjani, Gesa; Scheffler, Dirk; Cosgrove, Vivian P.; Ahlswede, Julia; Woiciechowsky, Christian; Budach, Volker

    2006-11-15

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

  5. Frame-Based Immobilization and Targeting for Stereotactic Body Radiation Therapy

    SciTech Connect

    Murray, Bryan C. . E-mail: bryan.murray@utsouthwestern.edu; Forster, Kenneth; Timmerman, Robert

    2007-07-01

    defined by the body frame fiducials. The ability to impose abdominal compression proved to be a simple way to reduce target and tissue motion. SBRT with Stereotactic Body Frame enables comfortable patient immobilization and facilitates repeated registering and re-registering of the patient to the frame. With the body frame, large-dose-per fraction treatment is possible for localized tumor deposits with the aim of attaining a more therapeutic result.

  6. Clinical Results of a Pilot Study on Stereovision-Guided Stereotactic Radiotherapy and Intensity Modulated Radiotherapy

    PubMed Central

    Li, Shidong; Kleinberg, Lawrence R.; Rigamonti, Daniele; Wharam, Moody D.; Rashid, Abdul; Jackson, Juan; Djajaputra, David; He, Shenjen; Creasey, Tunisia; DeWeese, Theodore L.

    2011-01-01

    Real-time stereovision-guidance has been introduced for efficient and convenient fractionated stereotactic radiotherapy (FSR) and image-guided intensity-modulated radiation therapy (IMRT). This first pilot study is to clinically evaluate its accuracy and precision as well as impact on treatment doses. Sixty-one FSR patients wearing stereotactic masks (SMs) and nine IMRT patients wearing flexible masks (FMs), were accrued. Daily target reposition was initially based-on biplane-radiographs and then adjusted in six degrees of freedom under real-time stereovision guidance. Mean and standard deviation of the head displacements measured the accuracy and precision. Head positions during beam-on times were measured with real-time stereovisions and used for determination of delivered doses. Accuracy ± precision in direction with the largest errors shows improvement from 0.4 ± 2.3 mm to 0.0 ± 1.0 mm in the inferior-to-superior direction for patients wearing SM or from 0.8 ± 4.3 mm to 0.4 ± 1.7 mm in the posterior-to-anterior direction for patients wearing FM. The image-guidance increases target volume coverage by >30% for small lesions. Over half of head position errors could be removed from the stereovision-guidance. Importantly, the technique allows us to check head position during beam-on time and makes it possible for having frameless head refixation without tight masks. PMID:21070083

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

    PubMed

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

    2015-05-01

    To evaluate the efficacy of hypofractionated stereotactic radiotherapy performed as reirradiation in combination with fotemustine or bevacizumab as salvage treatment in patients with recurrent malignant glioma. Between May 2006 and December 2013, 54 patients with recurrent malignant glioma received hypofractionated stereotactic radiotherapy (HSRT, 25 Gy in 5-Gy fractions) plus either fotemustine or bevacizumab at University of Rome Sapienza, Sant'Andrea Hospital. All patients had Karnofsky performance score (KPS) ≥ 60 and were previously treated with standard chemoradiotherapy. Forty-two patients had a GBM and 12 patients had an anaplastic astrocytoma (AA). The median overall survival (OS) time and 12-month OS rates after HSRT was 11 months and 30 % for patients treated with HSRT plus bevacizumab and 8.3 months and 5 % for those treated with HSRT plus fotemustine (p = 0.01). Median PFS times were 4 and 6 months for patients treated with HSRT plus fotemustine or bevacizumab, respectively (p = 0.01). KPS > 70 (p = 0.04), AA histology, and the treatment with bevacizumab were independent favourable prognostic factors for OS. In general, both treatments were well tolerated with relatively low treatment-related toxicity. HSRT combined with bevacizumab or fotemustine may represent a feasible treatment option for patients with progressive malignant gliomas, although most of the tumors recur in a few months. Efficacy of bevacizumab or alkylating agents in combination with different radiation schedules needs to be evaluated in prospective studies. PMID:25702193

  8. Effects of combined sunitinib and extracranial stereotactic radiotherapy on bone marrow hematopoiesis

    PubMed Central

    Kao, Johnny; Timmins, Jonathan; Ozao-Choy, Junko; Packer, Stuart

    2016-01-01

    There is considerable interest in deploying stereotactic body radiotherapy in combination with immune therapy for patients with extracranial oligometastases. In addition to angiogenesis inhibition, sunitinib appears to mediate antitumor immunity through effects on circulating monocytic cells. The current study investigated the effects of combined sunitinib and stereotactic radiotherapy on hematopoiesis. As part of a phase I/II clinical trial utilizing concurrent sunitinib (25–50 mg on days 1–28) and image-guided radiation therapy (40–50 Gy in 10 fractions starting on days 8–19) for patients with metastatic cancer, the complete blood count, platelet count and automatic differential were performed pretreatment and on days 8 and 19. On average, sunitinib monotherapy for 7 days resulted in a 33% decrease in monocytes and an 18% decrease in neutrophils (P<0.01 for all). Compared to sunitinib alone, combined sunitinib and radiation resulted in a further decrease in neutrophils, lymphocytes and platelets (P<0.05). Following sunitinib and radiation treatment, a greater than average decrease in monocytes (≥200/µl) was associated with a significant increase in progression-free and overall survival times. This exploratory study provides further evidence that monocytes represent a potential biomarker in patients with solid tumors treated with sunitinib. PMID:27602153

  9. A preplanning method for stereotactic radiosurgery to improve treatment workflow.

    PubMed

    Ahn, Kang-Hyun; Ozturk, Naim; Smith, Brett; Slavin, Konstantin V; Koshy, Matthew; Aydogan, Bulent

    2016-01-01

    Frame-based stereotactic radiosurgery (SRS) requires fixation of an invasive head ring to ensure accurate targeting. Minimizing waiting time with a fixed head ring is important for patient comfort and satisfaction. We report a practical preplanning solution for the Brainlab iPlan treatment planning system that reduces waiting time by expediting the planning process on treatment day. A water-filled anthropomorphic head phantom was used to acquire a surrogate CT image set for preplanning and fused with patient's MRI, which was obtained before the day of treatment. Once an acceptable preplan was obtained, it was saved as a plan template and the phantom image set was removed from the Brainlab database to prevent any confusion and mix-up of image sets. On the treatment day, the patient's CT and MRI were fused, and the customized beam settings of the preplan template were then applied and optimized. Up to 10-fold of reduction in treatment plan time was demonstrated by bench testing with multiple planners and a variety of cases. Loading the plan template and fine-tuning the preconfigured beam settings took only a small fraction of the preplan time to restore the conformity and dose falloff comparable to those of the preplan. For instance, preplan time was 2 hr for a two-isocenter case, whereas, it took less than 20 min for a less experienced planner to plan it on the day of treat-ment using the preplan method. The SRS preplanning technique implemented in this study for the Brainlab iPlan treatment planning system offers an opportunity to explore possible beam configurations thoroughly, optimize planning parameters, resolve gantry angle clearance issues, and communicate and address challenges with physicians before the treatment day. Preplanning has been proven to improve plan quality and to improve efficiency in our clinic, especially for multiple-isocenter and dosimetrically challenging cases. PMID:27167274

  10. Stereotactic Body Radiotherapy and Gemcitabine for Locally Advanced Pancreatic Cancer

    SciTech Connect

    Mahadevan, Anand; Jain, Sanjay; Goldstein, Michael; Miksad, Rebecca; Pleskow, Douglas; Sawhney, Mandeep; Brennan, Darren M.D.; Callery, Mark; Vollmer, Charles

    2010-11-01

    Purpose: Patients with nonmetastatic locally advanced unresectable pancreatic cancer have a dismal prognosis. Conventional concurrent chemoradiotherapy requires 6 weeks of daily treatment and can be arduous. We explored the safety and effectiveness of a 3-day course of hypofractionated stereotactic body radiotherapy (SBRT) followed by gemcitabine in this population. Patients and Methods: A total of 36 patients with nonmetastatic, locally advanced, unresectable pancreatic cancer with {>=}12 months of follow-up were included. They received three fractions of 8, 10, or 12 Gy (total dose, 24-36 Gy) of SBRT according to the tumor location in relation to the stomach and duodenum, using fiducial-based respiratory motion tracking on a robotic radiosurgery system. The patients were then offered gemcitabine for 6 months or until tolerance or disease progression. Results: With an overall median follow-up of 24 months (range, 12-33), the local control rate was 78%, the median overall survival time was 14.3 months, the median carbohydrate antigen 19-9-determined progression-free survival time was 7.9 months, and the median computed tomography-determined progression-free survival time was 9.6 months. Of the 36 patients, 28 (78%) eventually developed distant metastases. Six patients (17%) were free of progression at the last follow-up visit (range, 13-30 months) as determined by normalized tumor markers with stable computed tomography findings. Nine Grade 2 (25%) and five Grade 3 (14%) toxicities attributable to SBRT occurred. Conclusion: Hypofractionated SBRT can be delivered quickly and effectively in patients with nonmetastatic, locally advanced, unresectable pancreatic cancer with acceptable side effects and minimal interference with gemcitabine chemotherapy.

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

    PubMed Central

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

    2016-01-01

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

  12. Stereotactic Radiotherapy for Unilateral Orbital Lymphoma and Orbital Pseudo-Tumors: A Planning Study

    SciTech Connect

    Chino, Kazumi Tanyi, James A.; Stea, Baldassarre

    2009-04-01

    Orbital lymphoma and Grave's ophthalmopathy (GO) are successfully treated with radiation therapy. The lenses are blocked to prevent cataract formation. However, blocking of the lens by traditional methods can be difficult for tumors located anteriorly and extending into the retrobulbar space. We present a series of 3 patients with orbital lymphoma and 1 with GO treated with stereotactic intensity modulated radiation therapy (IMRT) to spare normal structures, including the lens. Three patients with orbital lymphomas and 1 with unilateral GO were treated with IMRT using a linac with stereotactic capabilities. Avoidance structures included the ipsilateral lens and globe, the contralateral lens and globe, the chiasm, and the brainstem. Two patients with orbital lymphoma were treated with 24 Gy in 12 fractions, and 1 patient was treated with 30.6 Gy in 17 fractions. The patient with GO was treated with 20 Gy in 10 fractions. The dosimetry was analyzed to determine the dose to normal tissues. Patient follow-up varies between 8 and 24 months. The mean minimal dose to the ipsilateral lens was 13.6% of the total dose, the mean maximal dose was 33.5%, and the mean median dose was 19.3%. The mean median dose to the contralateral eye was 1.1% of the total dose. The mean median dose to the chiasm was 14.9% of the total dose. The mean median dose to the brainstem was 1.9% of the total dose. No cataracts or other complications were noted in the 4 patients treated with this technique so far. IMRT gives a more conformal treatment to the orbital contents while sparing normal tissues such as the ipsilateral lens and adjacent critical structures. This should result in fewer complications such as cataracts.

  13. Quantitative evaluation of 3D dosimetry for stereotactic volumetric-modulated arc delivery using COMPASS.

    PubMed

    Vikraman, Subramani; Manigandan, Durai; Karrthick, Karukkupalayam Palaniappan; Sambasivaselli, Raju; Senniandavar, Vellaingiri; Ramu, Mahendran; Rajesh, Thiyagarajan; Lutz, Muller; Muthukumaran, Manavalan; Karthikeyan, Nithyanantham; Tejinder, Kataria

    2015-01-01

    The purpose of this study was to evaluate quantitatively the patient-specific 3D dosimetry tool COMPASS with 2D array MatriXX detector for stereotactic volumetric-modulated arc delivery. Twenty-five patients CT images and RT structures from different sites (brain, head & neck, thorax, abdomen, and spine) were taken from CyberKnife Multiplan planning system for this study. All these patients underwent radical stereotactic treatment in CyberKnife. For each patient, linac based volumetric-modulated arc therapy (VMAT) stereotactic plans were generated in Monaco TPS v3.1 using Elekta Beam Modulator MLC. Dose prescription was in the range of 5-20 Gy per fraction. Target prescription and critical organ constraints were tried to match the delivered treatment plans. Each plan quality was analyzed using conformity index (CI), conformity number (CN), gradient Index (GI), target coverage (TC), and dose to 95% of volume (D95). Monaco Monte Carlo (MC)-calculated treatment plan delivery accuracy was quantitatively evaluated with COMPASS-calculated (CCA) dose and COMPASS indirectly measured (CME) dose based on dose-volume histogram metrics. In order to ascertain the potential of COMPASS 3D dosimetry for stereotactic plan delivery, 2D fluence verification was performed with MatriXX using MultiCube phantom. Routine quality assurance of absolute point dose verification was performed to check the overall delivery accuracy. Quantitative analyses of dose delivery verification were compared with pass and fail criteria of 3 mm and 3% distance to agreement and dose differences. Gamma passing rate was compared with 2D fluence verification from MatriXX with MultiCube. Comparison of COMPASS reconstructed dose from measured fluence and COMPASS computed dose has shown a very good agreement with TPS calculated dose. Each plan was evaluated based on dose volume parameters for target volumes such as dose at 95% of volume (D95) and average dose. For critical organs dose at 20% of volume (D20), dose

  14. 10 CFR 35.2645 - Records of periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Records of periodic spot-checks for gamma stereotactic... MATERIAL Records § 35.2645 Records of periodic spot-checks for gamma stereotactic radiosurgery units. (a) A... and intercom systems, timer termination, treatment table retraction mechanism, and stereotactic...

  15. 10 CFR 35.2645 - Records of periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of periodic spot-checks for gamma stereotactic... MATERIAL Records § 35.2645 Records of periodic spot-checks for gamma stereotactic radiosurgery units. (a) A... and intercom systems, timer termination, treatment table retraction mechanism, and stereotactic...

  16. 10 CFR 35.2645 - Records of periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Records of periodic spot-checks for gamma stereotactic... MATERIAL Records § 35.2645 Records of periodic spot-checks for gamma stereotactic radiosurgery units. (a) A... and intercom systems, timer termination, treatment table retraction mechanism, and stereotactic...

  17. 10 CFR 35.2645 - Records of periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Records of periodic spot-checks for gamma stereotactic... MATERIAL Records § 35.2645 Records of periodic spot-checks for gamma stereotactic radiosurgery units. (a) A... and intercom systems, timer termination, treatment table retraction mechanism, and stereotactic...

  18. Outcomes for Spine Stereotactic Body Radiation Therapy and an Analysis of Predictors of Local Recurrence

    SciTech Connect

    Bishop, Andrew J.; Tao, Randa; Rebueno, Neal C.; Christensen, Eva N.; Allen, Pamela K.; Wang, Xin A.; Amini, Behrang; Tannir, Nizar M.; Tatsui, Claudio E.; Rhines, Laurence D.; Li, Jing; Chang, Eric L.; Brown, Paul D.; Ghia, Amol J.

    2015-08-01

    Purpose: To investigate local control, survival outcomes, and predictors of local relapse for patients treated with spine stereotactic body radiation therapy. Methods and Materials: We reviewed the records of 332 spinal metastases consecutively treated with stereotactic body radiation therapy between 2002 and 2012. The median follow-up for all living patients was 33 months (range, 0-111 months). Endpoints were overall survival and local control (LC); recurrences were classified as either in-field or marginal. Results: The 1-year actuarial LC and overall survival rates were 88% and 64%, respectively. Patients with local relapses had poorer dosimetric coverage of the gross tumor volume (GTV) compared with patients without recurrence (minimum dose [Dmin] biologically equivalent dose [BED] 23.9 vs 35.1 Gy, P<.001; D98 BED 41.8 vs 48.1 Gy, P=.001; D95 BED 47.2 vs 50.5 Gy, P=.004). Furthermore, patients with marginal recurrences had poorer prescription coverage of the GTV (86% vs 93%, P=.01) compared with those with in-field recurrences, potentially because of more upfront spinal canal disease (78% vs 24%, P=.001). Using a Cox regression univariate analysis, patients with a GTV BED Dmin ≥33.4 Gy (median dose) (equivalent to 14 Gy in 1 fraction) had a significantly higher 1-year LC rate (94% vs 80%, P=.001) compared with patients with a lower GTV BED Dmin; this factor was the only significant variable on multivariate Cox analysis associated with LC (P=.001, hazard ratio 0.29, 95% confidence interval 0.14-0.60) and also was the only variable significant in a separate competing risk multivariate model (P=.001, hazard ratio 0.30, 95% confidence interval 0.15-0.62). Conclusions: Stereotactic body radiation therapy offers durable control for spinal metastases, but there is a subset of patients that recur locally. Patients with local relapse had significantly poorer tumor coverage, which was likely attributable to treatment planning directives that prioritized the

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

    SciTech Connect

    Dunavoelgyi, Roman; Dieckmann, Karin; Gleiss, Andreas; Sacu, Stefan; Kircher, Karl; Georgopoulos, Michael; Georg, Dietmar; Zehetmayer, Martin; Poetter, Richard

    2012-05-01

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

  20. Cone Beam CT Image Guidance for Intracranial Stereotactic Treatments: Comparison With a Frame Guided Set-Up

    SciTech Connect

    Masi, Laura Casamassima, Franco; Polli, Caterina; Menichelli, Claudia; Bonucci, Ivano; Cavedon, Carlo

    2008-07-01

    Purpose: An analysis is performed of the setup errors measured by a kV cone beam computed tomography (CBCT) for intracranial stereotactic radiotherapy (SRT) patients immobilized by a thermoplastic mask and a bite-block and positioned using stereotactic coordinates. We evaluated the overall positioning precision and accuracy of the immobilizing and localizing systems. The potential of image-guided radiotherapy to replace stereotactic methods is discussed. Methods and Materials: Fifty-seven patients received brain SRT. After a frame-guided setup, before each fraction (131 fractions), a CBCT was acquired and the detected displacements corrected online. Translational and rotational errors were analyzed calculating overall mean and standard deviation. A separate analysis was performed for bite-block (in conjunction with mask) and for simple thermoplastic mask. Interobserver variability for CBCT three-dimensional registration was assessed. The residual error after correction and intrafractional motion were calculated. Results: The mean module of the three-dimensional displacement vector was 3.0 {+-} 1.4 mm. Setup errors for bite block and mask were smaller (2.9 {+-} 1.3 mm) than those for thermoplastic mask alone (3.2 {+-} 1.5 mm), but statistical significance was not reached (p = 0.15). Interobserver variability was negligible. The maximum margin calculated for residual errors and intra fraction motion was small but not negligible (1.57 mm). Conclusions: Considering the detected setup errors, daily image guidance is essential for the efficacy of SRT treatments when mask immobilization is used, and even when a bite-block is used in conjunction. The frame setup is still used as a starting point for the opportunity of rotational corrections. Residual margins after on-line corrections must be evaluated.

  1. Fractional oscillator.

    PubMed

    Stanislavsky, A A

    2004-11-01

    We consider a fractional oscillator which is a generalization of the conventional linear oscillator in the framework of fractional calculus. It is interpreted as an ensemble average of ordinary harmonic oscillators governed by a stochastic time arrow. The intrinsic absorption of the fractional oscillator results from the full contribution of the harmonic oscillator ensemble: these oscillators differ a little from each other in frequency so that each response is compensated by an antiphase response of another harmonic oscillator. This allows one to draw a parallel in the dispersion analysis for media described by a fractional oscillator and an ensemble of ordinary harmonic oscillators with damping. The features of this analysis are discussed. PMID:15600586

  2. CT-guided stereotactic neurosurgery: experience in 24 cases with a new stereotactic system.

    PubMed Central

    Thomas, D G; Anderson, R E; du Boulay, G H

    1984-01-01

    Twenty-four cases have been operated upon using a prototype Brown-Roberts-Wells, CT-guided stereotactic neurosurgical system. This device has proved to be practical and flexible in clinical use. No CT scanner modifications were required, a fact which simplified its use in more than one hospital. Multiple targets can be biopsied with ease and relative safety. Drainage and other therapeutic procedures can be carried out with minimal hazard. Future applications of this system may include its use with NMR and PET images. Images PMID:6363629

  3. Australia's Next Top Fraction Model

    ERIC Educational Resources Information Center

    Gould, Peter

    2013-01-01

    Peter Gould suggests Australia's next top fraction model should be a linear model rather than an area model. He provides a convincing argument and gives examples of ways to introduce a linear model in primary classrooms.

  4. Role of stereotactic radiosurgery with a linear accelerator in treatment of intracranial arteriovenous malformations and tumors in children.

    PubMed

    Loeffler, J S; Rossitch, E; Siddon, R; Moore, M R; Rockoff, M A; Alexander, E

    1990-05-01

    Between 1986 and 1988, 16 children were treated for 10 arteriovenous malformations and 6 recurrent intracranial tumors with stereotactic radiation therapy using a modified Clinac 6/100 linear accelerator. The median age of our patients was 10.5 years. For the group with arteriovenous malformation, follow-up ranged from 6 months to 37 months (median was 20 months). No patient bled during the follow-up period. Five of eight patients with follow-up longer than 12 months have achieved complete obliteration of their arteriovenous malformation by angiogram. The four remaining patients who have not achieved a complete obliteration are awaiting their 2-year posttreatment angiogram. The other patient has been treated within the year and have not yet been studied. Five of the six recurrent tumor patients are alive with a median follow-up of 8 months. The remaining patient was controlled locally, but he died of recurrent disease outside the area treated with radiosurgery. The radiographic responses of these patients have included three complete responses, two substantial reductions in tumor volume (greater than 50%) and one stabilization. Despite previous radiotherapy, there have been no significant complications in these patients. We conclude that stereotactic radiation therapy using a standard linear accelerator is an effective and safe technique in the treatment of selected intracranial arteriovenous malformations and tumors in children. In addition, stereotactic radiosurgery may have unique applications in the treatment of localized primary and recurrent pediatric brain tumors. PMID:2184409

  5. Stereotactic body radiation therapy for nonmetastatic lung cancer: An analysis of 75 patients treated over 5 years

    SciTech Connect

    Beitler, Jonathan J. . E-mail: jbeitler92@alumni.gsb.columbia.edu; Badine, Edgard A.; El-Sayah, Danny; Makara, Denise; Friscia, Phillip; Silverman, Phillip; Terjanian, Terenig

    2006-05-01

    Purpose: Non-small-cell lung cancer (NSCLC) may not be medically operable even in patients with surgically resectable disease. For patients who either refuse surgery or are medically inoperable, radiation therapy may be the best therapeutic choice. Stereotactic body radiation therapy (SBRT) employs external fixation and hypofractionation to deliver a high dose per fraction of radiation to a small target volume. Methods and Materials: Retrospective review of 75 patients treated over 5 years at Staten Island University Hospital as definitive treatment for NSCLC or presumed NSCLC. Patients received a median of 5 fractions of 8 Gy per fraction over 27 days. Results: Overall 1-, 2-, and 5-year actuarial survivals were 63%, 45%, and 17%. Patients with a gross tumor volume (GTV) less than 65 cm{sup 3} enjoyed a longer median survival (25.7 vs. 9.9 months, p < 0.003), and at 5 years, the actuarial survival for the patients with GTVs less than 65 cm{sup 3} was 24% vs. 0% for those with GTVs larger than 65 cm{sup 3}. Conclusions: Stereotactic body radiation therapy as delivered was ineffective for curing the patients whose GTVs were larger than 65 cm{sup 3}. SBRT was promising for those with GTVs less than 65 cm{sup 3}.

  6. Comparison of Two RapidArc Delivery Strategies in Stereotactic Body Radiotherapy of Peripheral Lung Cancer with Flattening Filter Free Beams

    PubMed Central

    Lin, Pei-Xian; Chen, Jian-Zhou; Kuang, Yu; Chen, Chuang-Zhen

    2015-01-01

    Purpose To investigate the performance of using partial arc (PA) and full arc with avoidance sectors (FAAS) in stereotactic body radiotherapy (SBRT) of peripheral lung cancer with flattening filter free (FFF) beams. Methods Eighteen patients with primary (T1 or T2) non-small-cell lung cancer (NSCLC) or lung metastatic were selected for this study. Nine patients with a gross tumor volume (GTV) <= 10 cc were designated as the small tumor group. The other nine patients with a GTV between 10 cc and 44 cc were assigned to the large tumor group. The treatment plans were generated in eighteen patients using PA and FAAS techniques, respectively, and delivered with a Varian TrueBeam Linac. Dosimetry of the target and organs at risk (OARs), monitor unit (MU), out-of-field dose, and delivery time were statistically analyzed. Delta4 and portal dosimetry were employed to evaluate the delivery accuracy. Results For the small tumor group, compared with the PA plans, the FAAS plans significantly achieved a lower MU/fraction, out-of-field dose and a shorter treatment time (p<0.05), but the target dose was slightly higher than that delivered by PA plans (p<0.05). For the large tumor group, the PA plans significantly attained a shorter treatment time (p<0.05), whereas MU/fraction, out-of-field dose and dose to OARs were comparable between the two plans (p>0.05). Furthermore, all plans generated from the eighteen patients achieved a high pass rate in patient-specific quality assurance, with all the gamma indices greater than 97% at the Γ3mm, 3% threshold. Conclusion This study suggests that the FAAS technique is more beneficial for the small tumor patients undergoing lung SBRT with FFF beams because of its higher treatment efficiency and MU reduction. However, for the large tumor patients, the PA technique is recommended due to its higher treatment efficiency. PMID:26131554

  7. Stereotactic radiosurgery in elderly patients with brain metastases.

    PubMed

    Minniti, Giuseppe; Esposito, Vincenzo; Clarke, Enrico; Scaringi, Claudia; Bozzao, Alessandro; Lanzetta, Gaetano; De Sanctis, Vitaliana; Valeriani, Maurizio; Osti, Mattia; Enrici, Riccardo Maurizi

    2013-02-01

    Stereotactic radiosurgery (SRS) has been increasingly employed as an alternative to whole brain radiation therapy in patients with brain metastases, with the aim to reduce its potential toxicity. We have evaluated clinical outcomes of SRS as initial treatment for brain metastases in patients 70 years and older. Between November 2007 and October 2011, 102 patients of 70 years and older with 1-4 metastases were treated with SRS. The primary end point of the study was overall survival. Secondary end points were local control and distant failure rates, cause of death, performance measurements, and toxicity of treatment. At a median follow-up of 11.0 months (range 1-48 months), median survival and median time to distant failure were 13.2 and 10 months, respectively. The 1- and 2-year survival rates were 63 and 28 %, and respective distant failure rates were 54 and 78 %. Forty-five patients succumbed to their extracranial disease and 14 patients died of progressive intracranial disease. Nine patients recurred locally after SRS. The 1- and 2-year local control rates were 90 and 84 %, respectively. Evaluation of neurocognitive function using the Mini-Mental State Examination (MMSE) showed no significant neurocognitive decline after SRS. MMSE score improved in 15 % of patients, worsened in 12 % of patients, and remained stable in the others. Severe neurological complications were reported in 7 (7 %) patients, requiring surgery or medical treatment. Initial treatment with SRS with close monitoring may represent a relatively safe treatment strategy associated with survival benefit, with outcomes similar to those reported in historical series of SRS for younger patients. PMID:23187817

  8. Stereotactic radiosurgery for four or more intracranial metastases

    SciTech Connect

    Bhatnagar, Ajay K.; Flickinger, John C. . E-mail: flickingerjc@upmc.edu; Kondziolka, Douglas; Lunsford, L. Dade

    2006-03-01

    Purpose: To evaluate the outcomes after a single stereotactic radiosurgery procedure for the care of patients with 4 or more intracranial metastases. Methods and Materials: Two hundred five patients with primary malignancies, including non-small-cell lung carcinoma (42%), breast carcinoma (23%), melanoma (17%), renal cell carcinoma (6%), colon cancer (3%), and others (10%) underwent gamma knife radiosurgery for 4 or more intracranial metastases at one time. The median number of brain metastases was 5 (range, 4-18) with a median total treatment volume of 6.8 cc (range, 0.6-51.0 cc). Radiosurgery was used as sole management (17% of patients), or in combination with whole brain radiotherapy (46%) or after failure of whole brain radiotherapy (38%). The median marginal radiosurgery dose was 16 Gy (range, 12-20 Gy). The mean follow-up was 8 months. Results: The median overall survival after radiosurgery for all patients was 8 months. The 1-year local control rate was 71%, and the median time to progressive/new brain metastases was 9 months. Using the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) classification system, the median overall survivals for RPA classes I, II, and III were 18, 9, and 3 months, respectively (p < 0.00001). Multivariate analysis revealed total treatment volume, age, RPA classification, and marginal dose as significant prognostic factors. The number of metastases was not statistically significant (p 0.333). Conclusion: Radiosurgery seems to provide survival benefit for patients with 4 or more intracranial metastases. Because total treatment volume was the most significant predictor of survival, the total volume of brain metastases, rather than the number of metastases, should be considered in identifying appropriate radiosurgery candidates.

  9. Proton Stereotactic Radiosurgery for the Treatment of Benign Meningiomas

    SciTech Connect

    Halasz, Lia M.; Bussiere, Marc R.; Dennis, Elizabeth R.; Niemierko, Andrzej; Chapman, Paul H.; Loeffler, Jay S.; Shih, Helen A.

    2011-12-01

    Purpose: Given the excellent prognosis for patients with benign meningiomas, treatment strategies to minimize late effects are important. One strategy is proton radiation therapy (RT), which allows less integral dose to normal tissue and greater homogeneity than photon RT. Here, we report the first series of proton stereotactic radiosurgery (SRS) used for the treatment of meningiomas. Methods and Materials: We identified 50 patients with 51 histologically proven or image- defined, presumed-benign meningiomas treated at our institution between 1996 and 2007. Tumors of <4 cm in diameter and located {>=}2 mm from the optic apparatus were eligible for treatment. Indications included primary treatment (n = 32), residual tumor following surgery (n = 8), and recurrent tumor following surgery (n = 10). The median dose delivered was 13 Gray radiobiologic equivalent (Gy[RBE]) (range, 10.0-15.5 Gy[RBE]) prescribed to the 90% isodose line. Results: Median follow-up was 32 months (range, 6-133 months). Magnetic resonance imaging at the most recent follow-up or time of progression revealed 33 meningiomas with stable sizes, 13 meningiomas with decreased size, and 5 meningiomas with increased size. The 3-year actuarial tumor control rate was 94% (95% confidence interval, 77%-98%). Symptoms were improved in 47% (16/ 34) of patients, unchanged in 44% (15/34) of patients, and worse in 9% (3/34) of patients. The rate of potential permanent adverse effects after SRS was 5.9% (3/51 patients). Conclusions: Proton SRS is an effective therapy for small benign meningiomas, with a potentially lower rate of long-term treatment-related morbidity. Longer follow-up is needed to assess durability of tumor control and late effects.

  10. Reirradiation Human Spinal Cord Tolerance for Stereotactic Body Radiotherapy

    SciTech Connect

    Sahgal, Arjun; Ma, Lijun; Weinberg, Vivian; Gibbs, Iris C.; Chao, Sam; Chang, Ung-Kyu; Werner-Wasik, Maria; Angelov, Liliyanna; Chang, Eric L.; Sohn, Moon-Jun; Soltys, Scott G.; Letourneau, Daniel; Ryu, Sam; Gerszten, Peter C.; Fowler, Jack; Wong, C. Shun; and others

    2012-01-01

    Purpose: We reviewed the treatment for patients with spine metastases who initially received conventional external beam radiation (EBRT) and were reirradiated with 1-5 fractions of stereotactic body radiotherapy (SBRT) who did or did not subsequently develop radiation myelopathy (RM). Methods and Materials: Spinal cord dose-volume histograms (DVHs) for 5 RM patients (5 spinal segments) and 14 no-RM patients (16 spine segments) were based on thecal sac contours at retreatment. Dose to a point within the thecal sac that receives the maximum dose (P{sub max}), and doses to 0.1-, 1.0-, and 2.0-cc volumes within the thecal sac were reviewed. The biologically effective doses (BED) using {alpha}/{beta} = 2 Gy for late spinal cord toxicity were calculated and normalized to a 2-Gy equivalent dose (nBED = Gy{sub 2/2}). Results: The initial conventional radiotherapy nBED ranged from {approx}30 to 50 Gy{sub 2/2} (median {approx}40 Gy{sub 2/2}). The SBRT reirradiation thecal sac mean P{sub max} nBED in the no-RM group was 20.0 Gy{sub 2/2} (95% confidence interval [CI], 10.8-29.2), which was significantly lower than the corresponding 67.4 Gy{sub 2/2} (95% CI, 51.0-83.9) in the RM group. The mean total P{sub max} nBED in the no-RM group was 62.3 Gy{sub 2/2} (95% CI, 50.3-74.3), which was significantly lower than the corresponding 105.8 Gy{sub 2/2} (95% CI, 84.3-127.4) in the RM group. The fraction of the total P{sub max} nBED accounted for by the SBRT P{sub max} nBED for the RM patients ranged from 0.54 to 0.78 and that for the no-RM patients ranged from 0.04 to 0.53. Conclusions: SBRT given at least 5 months after conventional palliative radiotherapy with a reirradiation thecal sac P{sub max} nBED of 20-25 Gy{sub 2/2} appears to be safe provided the total P{sub max} nBED does not exceed approximately 70 Gy{sub 2/2}, and the SBRT thecal sac P{sub max} nBED comprises no more than approximately 50% of the total nBED.

  11. Estimated Risk Level of Unified Stereotactic Body Radiation Therapy Dose Tolerance Limits for Spinal Cord.

    PubMed

    Grimm, Jimm; Sahgal, Arjun; Soltys, Scott G; Luxton, Gary; Patel, Ashish; Herbert, Scott; Xue, Jinyu; Ma, Lijun; Yorke, Ellen; Adler, John R; Gibbs, Iris C

    2016-04-01

    A literature review of more than 200 stereotactic body radiation therapy spine articles from the past 20 years found only a single article that provided dose-volume data and outcomes for each spinal cord of a clinical dataset: the Gibbs 2007 article (Gibbs et al, 2007(1)), which essentially contains the first 100 stereotactic body radiation therapy (SBRT) spine treatments from Stanford University Medical Center. The dataset is modeled and compared in detail to the rest of the literature review, which found 59 dose tolerance limits for the spinal cord in 1-5 fractions. We partitioned these limits into a unified format of high-risk and low-risk dose tolerance limits. To estimate the corresponding risk level of each limit we used the Gibbs 2007 clinical spinal cord dose-volume data for 102 spinal metastases in 74 patients treated by spinal radiosurgery. In all, 50 of the patients were previously irradiated to a median dose of 40Gy in 2-3Gy fractions and 3 patients developed treatment-related myelopathy. These dose-volume data were digitized into the dose-volume histogram (DVH) Evaluator software tool where parameters of the probit dose-response model were fitted using the maximum likelihood approach (Jackson et al, 1995(3)). Based on this limited dataset, for de novo cases the unified low-risk dose tolerance limits yielded an estimated risk of spinal cord injury of ≤1% in 1-5 fractions, and the high-risk limits yielded an estimated risk of ≤3%. The QUANTEC Dmax limits of 13Gy in a single fraction and 20Gy in 3 fractions had less than 1% risk estimated from this dataset, so we consider these among the low-risk limits. In the previously irradiated cohort, the estimated risk levels for 10 and 14Gy maximum cord dose limits in 5 fractions are 0.4% and 0.6%, respectively. Longer follow-up and more patients are required to improve the risk estimates and provide more complete validation. PMID:27000514

  12. Indirect Tumor Cell Death After High-Dose Hypofractionated Irradiation: Implications for Stereotactic Body Radiation Therapy and Stereotactic Radiation Surgery

    SciTech Connect

    Song, Chang W.; Lee, Yoon-Jin; Griffin, Robert J.; Park, Inhwan; Koonce, Nathan A.; Hui, Susanta; Kim, Mi-Sook; Dusenbery, Kathryn E.; Sperduto, Paul W.; Cho, L. Chinsoo

    2015-09-01

    Purpose: The purpose of this study was to reveal the biological mechanisms underlying stereotactic body radiation therapy (SBRT) and stereotactic radiation surgery (SRS). Methods and Materials: FSaII fibrosarcomas grown subcutaneously in the hind limbs of C3H mice were irradiated with 10 to 30 Gy of X rays in a single fraction, and the clonogenic cell survival was determined with in vivo–in vitro excision assay immediately or 2 to 5 days after irradiation. The effects of radiation on the intratumor microenvironment were studied using immunohistochemical methods. Results: After cells were irradiated with 15 or 20 Gy, cell survival in FSaII tumors declined for 2 to 3 days and began to recover thereafter in some but not all tumors. After irradiation with 30 Gy, cell survival declined continuously for 5 days. Cell survival in some tumors 5 days after 20 to 30 Gy irradiation was 2 to 3 logs less than that immediately after irradiation. Irradiation with 20 Gy markedly reduced blood perfusion, upregulated HIF-1α, and increased carbonic anhydrase-9 expression, indicating that irradiation increased tumor hypoxia. In addition, expression of VEGF also increased in the tumor tissue after 20 Gy irradiation, probably due to the increase in HIF-1α activity. Conclusions: Irradiation of FSaII tumors with 15 to 30 Gy in a single dose caused dose-dependent secondary cell death, most likely by causing vascular damage accompanied by deterioration of intratumor microenvironment. Such indirect tumor cell death may play a crucial role in the control of human tumors with SBRT and SRS.

  13. Stereotactic Body Radiotherapy for Metastatic and Recurrent Ewing Sarcoma and Osteosarcoma

    PubMed Central

    Brown, Lindsay C.; Lester, Rachael A.; Grams, Michael P.; Haddock, Michael G.; Olivier, Kenneth R.; Arndt, Carola A. S.; Rose, Peter S.; Laack, Nadia N.

    2014-01-01

    Background. Radiotherapy has been utilized for metastatic and recurrent osteosarcoma and Ewing sarcoma (ES), in order to provide palliation and possibly prolong overall or progression-free survival. Stereotactic body radiotherapy (SBRT) is convenient for patients and offers the possibility of increased efficacy. We report our early institutional experience using SBRT for recurrent and metastatic osteosarcoma and Ewing sarcoma. Methods. We reviewed all cases of osteosarcoma or ES treated with SBRT between 2008 and 2012. Results. We identified 14 patients with a total of 27 lesions from osteosarcoma (n = 19) or ES (n = 8). The median total curative/definitive SBRT dose delivered was 40 Gy in 5 fractions (range, 30–60 Gy in 3–10 fractions). The median total palliative SBRT dose delivered was 40 Gy in 5 fractions (range, 16–50 Gy in 1–10 fractions). Two grade 2 and 1 grade 3 late toxicities occurred, consisting of myonecrosis, avascular necrosis with pathologic fracture, and sacral plexopathy. Toxicity was seen in the settings of concurrent chemotherapy and reirradiation. Conclusions. This descriptive report suggests that SBRT may be a feasible local treatment option for patients with osteosarcoma and ES. However, significant toxicity can result, and thus systematic study is warranted to clarify efficacy and characterize long-term toxicity. PMID:25548538

  14. The tolerance of gastrointestinal organs to stereotactic body radiation therapy: what do we know so far?

    PubMed Central

    Thomas, Tarita O.; Hasan, Shaakir; Small, William; Herman, Joseph M.; Lock, Michael; Kim, Edward Y.; Mayr, Nina A.; Teh, Bin S.

    2014-01-01

    As stereotactic body radiation therapy (SBRT) for gastrointestinal (GI) gains popularity, there is a need to optimize doses and fractionation to minimize GI toxicity. GI organs that have classically developed radiation-induced toxicity include the liver & biliary system, small bowel, esophagus, and rectum. While the literature quantifies dose restrictions for these organs under standard fractionation, there is limited data regarding toxicity with the ablative dose schedules used in SBRT. We conducted a review of the literature to identify prospective and retrospective studies that detail GI toxicities when SBRT was employed. Based on the literature, the median SBRT dose for abdominal and thoracic tumors ranged from 24 to 60 Gy, at 5 to 25 Gy per fraction. The respective observed frequencies of grade 3 and 4 toxicities for the liver, biliary system, small bowel, and esophagus were variable among different studies. Typically, patients who suffered grade 3 and 4 toxicities were more likely to have had some form of systemic therapy as well. The effect of dose, fractionation, timing, and volume on GI toxicities has been described in the literature but more data is necessary to develop uniform treatment guidelines for SBRT. PMID:24982772

  15. Extrapolation of Normal Tissue Complication Probability for Different Fractionations in Liver Irradiation

    SciTech Connect

    Tai An; Erickson, Beth; Li, X. Allen

    2009-05-01

    Purpose: The ability to predict normal tissue complication probability (NTCP) is essential for NTCP-based treatment planning. The purpose of this work is to estimate the Lyman NTCP model parameters for liver irradiation from published clinical data of different fractionation regimens. A new expression of normalized total dose (NTD) is proposed to convert NTCP data between different treatment schemes. Method and Materials: The NTCP data of radiation- induced liver disease (RILD) from external beam radiation therapy for primary liver cancer patients were selected for analysis. The data were collected from 4 institutions for tumor sizes in the range of of 8-10 cm. The dose per fraction ranged from 1.5 Gy to 6 Gy. A modified linear-quadratic model with two components corresponding to radiosensitive and radioresistant cells in the normal liver tissue was proposed to understand the new NTD formalism. Results: There are five parameters in the model: TD{sub 50}, m, n, {alpha}/{beta} and f. With two parameters n and {alpha}/{beta} fixed to be 1.0 and 2.0 Gy, respectively, the extracted parameters from the fitting are TD{sub 50}(1) = 40.3 {+-} 8.4Gy, m =0.36 {+-} 0.09, f = 0.156 {+-} 0.074 Gy and TD{sub 50}(1) = 23.9 {+-} 5.3Gy, m = 0.41 {+-} 0.15, f = 0.0 {+-} 0.04 Gy for patients with liver cirrhosis scores of Child-Pugh A and Child-Pugh B, respectively. The fitting results showed that the liver cirrhosis score significantly affects fractional dose dependence of NTD. Conclusion: The Lyman parameters generated presently and the new form of NTD may be used to predict NTCP for treatment planning of innovative liver irradiation with different fractionations, such as hypofractioned stereotactic body radiation therapy.

  16. Stereotactic ventral pallidotomy for Parkinson's disease.

    PubMed

    Dogali, M; Fazzini, E; Kolodny, E; Eidelberg, D; Sterio, D; Devinsky, O; Berić, A

    1995-04-01

    Eighteen patients with medically intractable Parkinson's disease that was characterized by bradykinesia, rigidity, and marked "on-off" fluctuations underwent stereotactic ventral pallidotomy under local anesthesia. Targeting was aided by anatomic coordinates derived from the MRI, intraoperative cell recordings, and electrical stimulation prior to lesioning. A nonsurgically treated group of seven similarly affected individuals was also followed. Assessment of motor function was made at baseline and at 3-month intervals for 1 year. Following the lesioning, patients improved in bradykinesia, rigidity, resting tremor, and balance with resolution of medication-induced contralateral dyskinesia. When compared with preoperative baseline, all quantifiable test scores after surgery improved significantly with the patients off medications for 12 hours: UPDRS by 65%, and CAPIT subtest scores on the contralateral limb by 38.2% and the ipsilateral limb by 24.2%. Walk scores improved by 45%. Medication requirements were unchanged, but the patients who had had surgery were able to tolerate larger doses because of reduced dyskinesia. Ventral pallidotomy produces statistically significant reduction in parkinsonism and contralateral "on" dyskinesia without morbidity or mortality and with a short hospitalization in Parkinson's disease patients for whom medical therapy has failed. PMID:7723966

  17. Repeat Stereotactic Radiosurgery for Acoustic Neuromas

    SciTech Connect

    Kano, Hideyuki; Kondziolka, Douglas; Niranjan, Ajay M.Ch.; Flannery, Thomas J.; Flickinger, John C.; Lunsford, L. Dade

    2010-02-01

    Purpose: To evaluate the outcome of repeat stereotactic radiosurgery (SRS) for acoustic neuromas, we assessed tumor control, clinical outcomes, and the risk of adverse radiation effects in patients whose tumors progressed after initial management. Methods and Materials: During a 21-year experience at our center, 1,352 patients underwent SRS as management for their acoustic neuromas. We retrospectively identified 6 patients who underwent SRS twice for the same tumor. The median patient age was 47 years (range, 35-71 years). All patients had imaging evidence of tumor progression despite initial SRS. One patient also had incomplete surgical resection after initial SRS. All patients were deaf at the time of the second SRS. The median radiosurgery target volume at the time of the initial SRS was 0.5 cc and was 2.1 cc at the time of the second SRS. The median margin dose at the time of the initial SRS was 13 Gy and was 11 Gy at the time of the second SRS. The median interval between initial SRS and repeat SRS was 63 months (range, 25-169 months). Results: At a median follow-up of 29 months after the second SRS (range, 13-71 months), tumor control or regression was achieved in all 6 patients. No patient developed symptomatic adverse radiation effects or new neurological symptoms after the second SRS. Conclusions: With this limited experience, we found that repeat SRS for a persistently enlarging acoustic neuroma can be performed safely and effectively.

  18. Stereotactic radiosurgery for intramedullary spinal arteriovenous malformations.

    PubMed

    Kalani, Maziyar A; Choudhri, Omar; Gibbs, Iris C; Soltys, Scott G; Adler, John R; Thompson, Patricia A; Tayag, Armine T; Samos, Cindy H; Chang, Steven D

    2016-07-01

    Spinal cord arteriovenous malformations (AVM) are rare lesions associated with recurrent hemorrhage and progressive ischemia. Occasionally a favorable location, size or vascular anatomy may allow management with endovascular embolization and/or microsurgical resection. For most, however, there is no good treatment option. Between 1997 and 2014, we treated 37 patients (19 females, 18 males, median age 30years) at our institution diagnosed with intramedullary spinal cord AVM (19 cervical, 12 thoracic, and six conus medullaris) with CyberKnife (Accuray, Sunnyvale, CA, USA) stereotactic radiosurgery. A history of hemorrhage was present in 50% of patients. The mean AVM volume of 2.3cc was treated with a mean marginal dose of 20.5Gy in a median of two sessions. Clinical and MRI follow-up were carried out annually, and spinal angiography was repeated at 3years. We report an overall obliteration rate of 19% without any post-treatment hemorrhagic events. In those AVM that did not undergo obliteration, significant volume reduction was noted at 3years. Although the treatment paradigm for spinal cord AVM continues to evolve, radiosurgical treatment is capable of safely obliterating or significantly shrinking most intramedullary spinal cord AVM. PMID:26869363

  19. New Strategies in Stereotactic Radiotherapy for Oligometastases.

    PubMed

    Palma, David A; Louie, Alexander V; Rodrigues, George B

    2015-12-01

    Patients with metastatic solid tumors are usually treated with palliative intent. Systemic therapy and palliative radiation are often used, with the goals of prolonging survival or maintaining quality of life, but not of cure. In contrast to this paradigm, the theory of oligometastasis suggests that some patients who have a small number of metastases may be amenable to cure if all lesions can be eradicated. Aggressive treatment of patients with oligometastases, using either surgery or radiotherapy, has become more common in the past decade, yet in most situations, no randomized evidence is available to support such an approach. Stereotactic ablative radiotherapy (SABR) is a novel treatment for oligometastases, delivering large doses of radiotherapy in only a few treatments, with excellent rates of local control, and appears to be an excellent noninvasive alternative to surgical resection of metastases. This article reviews recent biologic and clinical data that support the existence of the oligometastatic state and discusses gaps in this evidence base. The emerging role for SABR in the management of this challenging patient population is discussed with a focus on ongoing clinical trials in an attempt to improve overall survival, delay progression, or induce immunologic anticancer effects through the abscopal effect. PMID:26626571

  20. let-7 Overexpression Leads to an Increased Fraction of Cells in G2/M, Direct Down-regulation of Cdc34, and Stabilization of Wee1 Kinase in Primary Fibroblasts*S⃞

    PubMed Central

    Legesse-Miller, Aster; Elemento, Olivier; Pfau, Sarah J.; Forman, Joshua J.; Tavazoie, Saeed; Coller, Hilary A.

    2009-01-01

    microRNAs play a critically important role in a wide array of biological processes including those implicated in cancer, neuro-degenerative and metabolic disorders, and viral infection. Although we have begun to understand microRNA biogenesis and function, experimental demonstration of their functional effects and the molecular mechanisms by which they function remains a challenge. Members of the let-7/miR-98 family play a critical role in cell cycle control with respect to differentiation and tumorigenesis. In this study, we show that exogenous addition of pre-let-7 in primary human fibroblasts results in a decrease in cell number and an increased fraction of cells in the G2/M cell cycle phase. Combining microarray techniques with DNA sequence analysis to identify potential let-7 targets, we discovered 838 genes with a let-7 binding site in their 3′-untranslated region that were down-regulated upon overexpression of let-7b. Among these genes is cdc34, the ubiquitin-conjugating enzyme of the Skp1/cullin/F-box (SCF) complex. Cdc34 protein levels are strongly down-regulated by let-7 overexpression. Reporter assays demonstrated direct regulation of the cdc34 3′-untranslated region by let-7. We hypothesized that low Cdc34 levels would result in decreased SCF activity, stabilization of the SCF target Wee1, and G2/M accumulation. Consistent with this hypothesis, small interfering RNA-mediated down-regulation of Wee1 reversed the G2/M phenotype induced by let-7 overexpression. We conclude that Cdc34 is a functional target of let-7 and that let-7 induces down-regulation of Cdc34, stabilization of the Wee1 kinase, and an increased fraction of cells in G2/M in primary fibroblasts. PMID:19126550

  1. Dose-Volume Parameters Predict for the Development of Chest Wall Pain After Stereotactic Body Radiation for Lung Cancer

    SciTech Connect

    Mutter, Robert W.; Liu Fan; Abreu, Andres; Yorke, Ellen; Jackson, Andrew; Rosenzweig, Kenneth E.

    2012-04-01

    Purpose: Chest wall (CW) pain has recently been recognized as an important adverse effect of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC). We developed a dose-volume model to predict the development of this toxicity. Methods and Materials: A total of 126 patients with primary, clinically node-negative NSCLC received three to five fractions of SBRT to doses of 40-60 Gy and were prospectively followed. The dose-absolute volume histograms of two different definitions of the CW as an organ at risk (CW3cm and CW2cm) were examined for all 126 patients. Results: With a median follow-up of 16 months, the 2-year estimated actuarial incidence of Grade {>=} 2 CW pain was 39%. The median time to onset of Grade {>=} 2 CW pain (National Cancer Institute Common Terminology Criteria for Adverse Events, Version 3.0) was 9 months. There was no predictive advantage for biologically corrected dose over physical dose. Neither fraction number (p = 0.07) nor prescription dose (p = 0.07) were significantly correlated with the development of Grade {>=} 2 CW pain. Cox Proportional Hazards analysis identified significant correlation with a broad range of dose-volume combinations, with the CW volume receiving 30 Gy (V30) as one of the strongest predictors (p < 0.001). CW2cm consistently enabled better prediction of CW toxicity. When a physical dose of 30 Gy was received by more than 70 cm{sup 3} of CW2cm, there was a significant correlation with Grade {>=} 2 CW pain (p = 0.004). Conclusions: CW toxicity after SBRT is common and long-term follow-up is needed to identify affected patients. A volume of CW {>=} 70 cm{sup 3} receiving 30 Gy is significantly correlated with Grade {>=} 2 CW pain. We are currently applying this constraint at our institution for patients receiving thoracic SBRT. An actuarial atlas of our data is provided as an electronic supplement to facilitate data-sharing and meta-analysis relating to CW pain.

  2. DOSE–VOLUME PARAMETERS PREDICT FOR THE DEVELOPMENT OF CHEST WALL PAIN AFTER STEREOTACTIC BODY RADIATION FOR LUNG CANCER

    PubMed Central

    Mutter, Robert W.; Liu, Fan; Abreu, Andres; Yorke, Ellen; Jackson, Andrew; Rosenzweig, Kenneth E.

    2013-01-01

    Purpose Chest wall (CW) pain has recently been recognized as an important adverse effect of stereotactic body radiation therapy (SBRT) for non–small-cell lung cancer (NSCLC). We developed a dose–volume model to predict the development of this toxicity. Methods and Materials A total of 126 patients with primary, clinically node-negative NSCLC received three to five fractions of SBRT to doses of 40–60 Gy and were prospectively followed. The dose–absolute volume histograms of two different definitions of the CW as an organ at risk (CW3cm and CW2cm) were examined for all 126 patients. Results With a median follow-up of 16 months, the 2-year estimated actuarial incidence of Grade ≥ 2 CW pain was 39%. The median time to onset of Grade ≥ 2 CW pain (National Cancer Institute Common Terminology Criteria for Adverse Events, Version 3.0) was 9 months. There was no predictive advantage for biologically corrected dose over physical dose. Neither fraction number (p = 0.07) nor prescription dose (p = 0.07) were significantly correlated with the development of Grade ≥ 2 CW pain. Cox Proportional Hazards analysis identified significant correlation with a broad range of dose-volume combinations, with the CW volume receiving 30 Gy (V30) as one of the strongest predictors (p < 0.001). CW2cm consistently enabled better prediction of CW toxicity. When a physical dose of 30 Gy was received by more than 70 cm3 of CW2cm, there was a significant correlation with Grade ≥ 2 CW pain (p = 0.004). Conclusions CW toxicity after SBRT is common and long-term follow-up is needed to identify affected patients. A volume of CW ≥ 70 cm3 receiving 30 Gy is significantly correlated with Grade ≥ 2 CW pain. We are currently applying this constraint at our institution for patients receiving thoracic SBRT. An actuarial atlas of our data is provided as an electronic supplement to facilitate data-sharing and meta-analysis relating to CW pain. PMID:21868173

  3. Stereotactic Body Radiation Therapy for Re-irradiation of Persistent or Recurrent Non-Small Cell Lung Cancer

    SciTech Connect

    Trovo, Marco; Minatel, Emilio; Durofil, Elena; Polesel, Jerry; Avanzo, Michele; Baresic, Tania; Bearz, Alessandra; Del Conte, Alessandro; Franchin, Giovanni; Gobitti, Carlo; Rumeileh, Imad Abu; Trovo, Mauro G.

    2014-04-01

    Purpose: To retrospectively assess toxicity and outcome of re-irradiation with stereotactic body radiation therapy (SBRT) in patients with recurrent or persistent non-small cell lung cancer (NSCLC), who were previously treated with radical radiation therapy (50-60 Gy). The secondary endpoint was to investigate whether there are dosimetric parameter predictors of severe radiation toxicity. Methods and Materials: The analysis was conducted in 17 patients with “in-field” recurrent/persistent centrally located NSCLC, who underwent re-irradiation with SBRT. SBRT consisted of 30 Gy in 5 to 6 fractions; these prescriptions would be equivalent for the tumor to 37.5 to 40 Gy, bringing the total 2-Gy-per-fraction cumulative dose to 87 to 100 Gy, considering the primary radiation therapy treatment. Actuarial analyses and survival were calculated by the Kaplan-Meier method, and P values were estimated by the log-rank test, starting from the date of completion of SBRT. Dosimetric parameters from the subgroups with and without grade ≥3 pulmonary toxicity were compared using a 2-tailed Student t test. Results: The median follow-up was 18 months (range, 4-57 months). Only 2 patients had local failure, corresponding to a local control rate of 86% at 1 year. The Kaplan-Meier estimates of overall survival (OS) rates at 1 and 2 years were 59% and 29%, respectively; the median OS was 19 months. Four patients (23%) experienced grade 3 radiation pneumonitis, and 1 patient developed fatal pneumonitis. One patient died of fatal hemoptysis 2 months after the completion of SBRT. Unexpectedly, heart maximum dose, D5 (minimum dose to at least 5% of the heart volume), and D10 were correlated with risk of radiation pneumonitis (P<.05). Conclusions: Re-irradiation with SBRT for recurrent/persistent centrally located NSCLC achieves excellent results in terms of local control. However, the high rate of severe toxicity reported in our study is of concern.

  4. Salvage Reirradiaton With Stereotactic Body Radiotherapy for Locally Recurrent Head-and-Neck Tumors

    SciTech Connect

    Cengiz, Mustafa; Ozyigit, Goekhan; Yazici, Goezde; Dogan, Ali; Yildiz, Ferah; Zorlu, Faruk; Guerkaynak, Murat; Gullu, Ibrahim H.; Hosal, Sefik; Akyol, Fadil

    2011-09-01

    Purpose: In this study, we present our results of reirradiation of locally recurrent head-and-neck cancer with image-guided, fractionated, frameless stereotactic body radiotherapy technique. Methods and Materials: From July 2007 to February 2009, 46 patients were treated using the CyberKnife (Accuray, Sunnyvale, CA) at the Department of Radiation Oncology, Hacettepe University, Ankara, Turkey. All patients had recurrent, unresectable, and previously irradiated head-and-neck cancer. The most prominent site was the nasopharynx (32.6%), and the most common histopathology was epidermoid carcinoma. The planning target volume was defined as the gross tumor volume identified on magnetic resonance imaging and computed tomography. There were 22 female and 24 male patients. Median age was 53 years (range, 19-87 years). The median tumor dose with stereotactic body radiotherapy was 30 Gy (range, 18-35 Gy) in a median of five (range, one to five) fractions. Results: Of 37 patients whose response to therapy was evaluated, 10 patients (27%) had complete tumor regression, 11 (29.8%) had partial response, and 10 (27%) had stable disease. Ultimate local disease control was achieved in 31 patients (83.8%). The overall survival was 11.93 months in median (ranged, 11.4 - 17.4 months), and the median progression free survival was 10.5 months. One-year progression-free survival and overall survival were 41% and 46%, respectively. Grade II or greater long-term complications were observed in 6 (13.3%) patients. On follow-up, 8 (17.3%) patients had carotid blow-out syndrome, and 7 (15.2%) patients died of bleeding from carotid arteries. We discovered that this fatal syndrome occurred only in patients with tumor surrounding carotid arteries and carotid arteries receiving all prescribed dose. Conclusions: Stereotactic body radiotherapy is an appealing treatment option for patients with recurrent head-and-neck cancer previously treated with radiation to high doses. Good local control with

  5. Outcomes and toxicities of stereotactic body radiation therapy for non-spine bone oligometastases

    PubMed Central

    Owen, Dawn; Laack, Nadia N.; Mayo, Charles S.; Garces, Yolanda I.; Park, Sean S.; Bauer, Heather J.; Nelson, Kathryn; Miller, Robert W.; Brown, Paul D.; Olivier, Kenneth R.

    2015-01-01

    Purpose Stereotactic body radiation therapy (SBRT) is being applied more widely for oligometastatic disease. This technique is now being used for non-spine bony metastases in addition to liver, spine, and lung. However, there are few studies examining the toxicity and outcomes of SBRT for non-spine bone metastases. Methods and Materials Between 2008 and 2012, 74 subjects with oligometastatic non-spine bony metastases of varying histologies were treated at the Mayo Clinic with SBRT. A total of 85 non-spine bony sites were treated. Median local control, overall survival, and progression-free survival were described. Acute toxicity (defined as toxicity <90 days) and late toxicity (defined as toxicity ≥90 days) were reported and graded as per standardized Common Toxicity Criteria for Adverse Events 4.0 criteria. Results The median age of patients treated was 60 years. The most common histology was prostate cancer (31%) and most patients had fewer than 3 sites of disease at the time of simulation (64%). Most of the non-spine bony sites lay within the pelvis (65%). Dose and fractionation varied but the most common prescription was 24 Gy/1 fraction. Local recurrence occurred in 7 patients with a median time to failure of 2.8 months. Local control was 91.8% at 1 year. With a median follow-up of 7.6 months, median SBRT specific overall survival and progression-free survival were 9.3 months and 9.7 months, respectively. Eighteen patients developed acute toxicity (mostly grade 1 and 2 fatigue and acute pain flare); 9 patients developed grade 1–2 late toxicities. Two patients developed pathologic fractures but both were asymptomatic. There were no late grade 3 or 4 toxicities. Conclusions Stereotactic body radiation therapy is a feasible and tolerable treatment for non-spine bony metastases. Longer follow-up will be needed to accurately determine late effects. PMID:24890360

  6. Evaluation of the peripheral dose in stereotactic radiotherapy and radiosurgery treatments

    SciTech Connect

    Di Betta, Erika; Fariselli, Laura; Bergantin, Achille; Locatelli, Federica; Del Vecchio, Antonella; Broggi, Sara; Fumagalli, Maria Luisa

    2010-07-15

    Purpose: The main purpose of this work was to compare peripheral doses absorbed during stereotactic treatment of a brain lesion delivered using different devices. These data were used to estimate the risk of stochastic effects. Methods: Treatment plans were created for an anthropomorphic phantom and delivered using a LINAC with stereotactic cones and a multileaf collimator, a CyberKnife system (before and after a supplemental shielding was applied), a TomoTherapy system, and a Gamma Knife unit. For each treatment, 5 Gy were prescribed to the target. Measurements were performed with thermoluminescent dosimeters inserted roughly in the position of the thyroid, sternum, upper lung, lower lung, and gonads. Results: Mean doses ranged from of 4.1 (Gamma Knife) to 62.8 mGy (LINAC with cones) in the thyroid, from 2.3 (TomoTherapy) to 30 mGy (preshielding CyberKnife) in the sternum, from 1.7 (TomoTherapy) to 20 mGy (preshielding CyberKnife) in the upper part of the lungs, from 0.98 (Gamma Knife) to 15 mGy (preshielding CyberKnife) in the lower part of the lungs, and between 0.3 (Gamma Knife) and 10 mGy (preshielding CyberKnife) in the gonads. Conclusions: The peripheral dose absorbed in the sites of interest with a 5 Gy fraction is low. Although the risk of adverse side effects calculated for 20 Gy delivered in 5 Gy fractions is negligible, in the interest of optimum patient radioprotection, further studies are needed to determine the weight of each contributor to the peripheral dose.

  7. Evaluation of the peripheral dose in stereotactic radiotherapy and radiosurgery treatments1

    PubMed Central

    Di Betta, Erika; Fariselli, Laura; Bergantin, Achille; Locatelli, Federica; Del Vecchio, Antonella; Broggi, Sara; Fumagalli, Maria Luisa

    2010-01-01

    Purpose: The main purpose of this work was to compare peripheral doses absorbed during stereotactic treatment of a brain lesion delivered using different devices. These data were used to estimate the risk of stochastic effects. Methods: Treatment plans were created for an anthropomorphic phantom and delivered using a LINAC with stereotactic cones and a multileaf collimator, a CyberKnife® system (before and after a supplemental shielding was applied), a TomoTherapy® system, and a Gamma Knife® unit. For each treatment, 5 Gy were prescribed to the target. Measurements were performed with thermoluminescent dosimeters inserted roughly in the position of the thyroid, sternum, upper lung, lower lung, and gonads. Results: Mean doses ranged from of 4.1 (Gamma Knife) to 62.8 mGy (LINAC with cones) in the thyroid, from 2.3 (TomoTherapy) to 30 mGy (preshielding CyberKnife) in the sternum, from 1.7 (TomoTherapy) to 20 mGy (preshielding CyberKnife) in the upper part of the lungs, from 0.98 (Gamma Knife) to 15 mGy (preshielding CyberKnife) in the lower part of the lungs, and between 0.3 (Gamma Knife) and 10 mGy (preshielding CyberKnife) in the gonads. Conclusions: The peripheral dose absorbed in the sites of interest with a 5 Gy fraction is low. Although the risk of adverse side effects calculated for 20 Gy delivered in 5 Gy fractions is negligible, in the interest of optimum patient radioprotection, further studies are needed to determine the weight of each contributor to the peripheral dose. PMID:20831066

  8. Recursive Partitioning Analysis Index Is Predictive for Overall Survival in Patients Undergoing Spine Stereotactic Body Radiation Therapy for Spinal Metastases

    SciTech Connect

    Chao, Samuel T.; Koyfman, Shlomo A.; Woody, Neil; Angelov, Lilyana; Soeder, Sherry L.; Reddy, Chandana A.; Rybicki, Lisa A.; Djemil, Toufik; Suh, John H.

    2012-04-01

    Purpose: To generate a prognostic index using recursive partitioning analysis (RPA) for patients undergoing spine stereotactic body radiation therapy (sSBRT) for spinal metastases (sMet). Methods and Materials: From an institutional review board-approved database, 174 patients were treated for sMet with sSBRT between February 2006 and August 2009. Median dose was 14 Gy (range, 8-24 Gy), typically in a single fraction (range, 1-5). Kaplan-Meier analysis was performed to detect any correlation between survival and histology. Histologies were divided into favorable (breast and prostate), radioresistant (renal cell, melanoma and sarcoma), and other (all other histologies). RPA was performed to identify any association of the following variables with overall survival (OS) following sSBRT: histology, gender, age, Karnofsky performance status (KPS), control of primary, extraosseous metastases, time from primary diagnosis (TPD), dose of sSBRT ({<=}14 Gy vs. >14 Gy), extent of spine disease (epidural only, bone and epidural, bone only), upfront or salvage treatment, presence of paraspinal extension, and previous surgery. Results: Median follow-up was 8.9 months. Median OS time from sSBRT was 10.7 months. Median OS intervals for favorable histologies were 14 months, 11.2 months for radioresistant histologies, and 7.3 months for other histologies (p = 0.02). RPA analysis resulted in three classes (p < 0.0001). Class 1 was defined as TPD of >30 months and KPS of >70; Class 2 was TPD of >30 months and KPS of {<=}70 or a TPD of {<=}30 months and age <70 years old; Class 3 was TPD of {<=}30 months and age {>=}70 years old. Median OS was 21.1 months for Class 1 (n = 59), 8.7 months for Class 2 (n = 104), and 2.4 months for Class 3 (n = 11). Conclusion: sSBRT patients treated for sMet have a wide variability in OS. We developed an RPA classification system that is predictive of OS. While many patients are treated for palliation of pain or to avoid symptomatic progression, this

  9. Inter- and Intrafraction Variability in Liver Position in Non-Breath-Hold Stereotactic Body Radiotherapy

    SciTech Connect

    Case, Robert B.; Sonke, Jan-Jakob; Moseley, Douglas J.; Kim, John; Brock, Kristy K.; Dawson, Laura A.

    2009-09-01

    Purpose: The inter- and intrafraction variability of liver position was assessed in patients with liver cancer treated with kilovoltage cone-beam computed tomography (CBCT)-guided stereotactic body radiotherapy. Methods and Materials: A total of 314 CBCT scans obtained in the treatment position immediately before and after each fraction were evaluated from 29 patients undergoing six-fraction, non-breath-hold stereotactic body radiotherapy for unresectable liver cancer. Off-line, the CBCT scans were sorted into 10 bins, according to the phase of respiration. The liver position (relative to the vertebral bodies) was measured using rigid alignment of the exhale CBCT liver with the exhale planning CT liver, following the alignment of the vertebrae. The interfraction liver position change was measured by comparing the pretreatment CBCT scans, and the intrafraction change was measured from the CBCT scans obtained immediately before and after each fraction. Results: The mean amplitude of liver motion for all patients was 1.8 mm (range, 0.1-5.7), 8.0 mm (range, 0.1-18.8), and 4.3 mm (range 0.1-12.1) in the medial-lateral (ML), craniocaudal (CC), and anteroposterior (AP) directions, respectively. The mean absolute ML, CC, and AP interfraction changes in liver position were 2.0 mm (90th percentile, 4.2), 3.5 mm (90th percentile, 7.3), and 2.3 mm (90th percentile, 4.7). The mean absolute intrafraction ML, CC, and AP changes were 1.3 mm (90th percentile, 2.9), 1.6 mm (90th percentile, 3.6), and 1.5 mm (90th percentile, 3.1), respectively. The interfraction changes were significantly larger than the intrafraction changes, with a CC systematic error of 2.9 and 1.1 mm, respectively. The intraobserver reproducibility ({sigma}, n = 29 fractions) was 1.3 mm in the ML, 1.4 mm in the CC, and 1.6 mm in the AP direction. Conclusion: Interfraction liver position changes relative to the vertebral bodies are an important source of geometric uncertainty, providing a rationale for

  10. Once-Weekly, High-Dose Stereotactic Body Radiotherapy for Lung Cancer: 6-Year Analysis of 60 Early-Stage, 42 Locally Advanced, and 7 Metastatic Lung Cancers

    SciTech Connect

    Salazar, Omar M. Sandhu, Taljit S.; Lattin, Paul B.; Chang, Jung H.; Lee, Choon K.; Groshko, Gayle A.; Lattin, Cheryl J.

    2008-11-01

    Purpose: To explore once-weekly stereotactic body radiotherapy (SBRT) in nonoperable patients with localized, locally advanced, or metastatic lung cancer. Methods and Materials: A total of 102 primary (89 untreated plus 13 recurrent) and 7 metastatic tumors were studied. The median follow-up was 38 months, the average patient age was 75 years. Of the 109 tumors studied, 60 were Stage I (45 IA and 15 IB), 9 were Stage II, 30 were Stage III, 3 were Stage IV, and 7 were metastases. SBRT only was given in 73% (40 Gy in four fractions to the planning target volume to a total dose of 53 Gy to the isocenter for a biologically effective dose of 120 Gy{sub 10}). SBRT was given as a boost in 27% (22.5 Gy in three fractions once weekly for a dose of 32 Gy at the isocenter) after 45 Gy in 25 fractions to the primary plus the mediastinum. The total biologically effective dose was 120 Gy{sub 10}. Respiration gating was used in 46%. Results: The overall response rate was 75%; 33% had a complete response. The overall response rate was 89% for Stage IA patients (40% had a complete response). The local control rate was 82%; it was 100% and 93% for Stage IA and IB patients, respectively. The failure rate was 37%, with 17% within the planning target volume. No Grade 3-4 acute toxicities developed in any patient; 12% and 7% of patients developed Grade 1 and 2 toxicities, respectively. Late toxicity, all Grade 2, developed in 3% of patients. The 5-year cause-specific survival rate for Stage I was 70% and was 74% and 64% for Stage IA and IB patients, respectively. The 3-year Stage III cause-specific survival rate was 30%. The patients with metastatic lung cancer had a 57% response rate, a 27% complete response rate, an 86% local control rate, a median survival time of 19 months, and 23% 3-year survival rate. Conclusions: SBRT is noninvasive, convenient, fast, and economically attractive; it achieves results similar to surgery for early or metastatic lung cancer patients who are older

  11. Fraction Reduction through Continued Fractions

    ERIC Educational Resources Information Center

    Carley, Holly

    2011-01-01

    This article presents a method of reducing fractions without factoring. The ideas presented may be useful as a project for motivated students in an undergraduate number theory course. The discussion is related to the Euclidean Algorithm and its variations may lead to projects or early examples involving efficiency of an algorithm.

  12. A comparison of robotic arm versus gantry linear accelerator stereotactic body radiation therapy for prostate cancer

    PubMed Central

    Avkshtol, Vladimir; Dong, Yanqun; Hayes, Shelly B; Hallman, Mark A; Price, Robert A; Sobczak, Mark L; Horwitz, Eric M; Zaorsky, Nicholas G

    2016-01-01

    Prostate cancer is the most prevalent cancer diagnosed in men in the United States besides skin cancer. Stereotactic body radiation therapy (SBRT; 6–15 Gy per fraction, up to 45 minutes per fraction, delivered in five fractions or less, over the course of approximately 2 weeks) is emerging as a popular treatment option for prostate cancer. The American Society for Radiation Oncology now recognizes SBRT for select low- and intermediate-risk prostate cancer patients. SBRT grew from the notion that high doses of radiation typical of brachytherapy could be delivered noninvasively using modern external-beam radiation therapy planning and delivery methods. SBRT is most commonly delivered using either a traditional gantry-mounted linear accelerator or a robotic arm-mounted linear accelerator. In this systematic review article, we compare and contrast the current clinical evidence supporting a gantry vs robotic arm SBRT for prostate cancer. The data for SBRT show encouraging and comparable results in terms of freedom from biochemical failure (>90% for low and intermediate risk at 5–7 years) and acute and late toxicity (<6% grade 3–4 late toxicities). Other outcomes (eg, overall and cancer-specific mortality) cannot be compared, given the indolent course of low-risk prostate cancer. At this time, neither SBRT device is recommended over the other for all patients; however, gantry-based SBRT machines have the abilities of treating larger volumes with conventional fractionation, shorter treatment time per fraction (~15 minutes for gantry vs ~45 minutes for robotic arm), and the ability to achieve better plans among obese patients (since they are able to use energies >6 MV). Finally, SBRT (particularly on a gantry) may also be more cost-effective than conventionally fractionated external-beam radiation therapy. Randomized controlled trials of SBRT using both technologies are underway. PMID:27574585

  13. A comparison of robotic arm versus gantry linear accelerator stereotactic body radiation therapy for prostate cancer.

    PubMed

    Avkshtol, Vladimir; Dong, Yanqun; Hayes, Shelly B; Hallman, Mark A; Price, Robert A; Sobczak, Mark L; Horwitz, Eric M; Zaorsky, Nicholas G

    2016-01-01

    Prostate cancer is the most prevalent cancer diagnosed in men in the United States besides skin cancer. Stereotactic body radiation therapy (SBRT; 6-15 Gy per fraction, up to 45 minutes per fraction, delivered in five fractions or less, over the course of approximately 2 weeks) is emerging as a popular treatment option for prostate cancer. The American Society for Radiation Oncology now recognizes SBRT for select low- and intermediate-risk prostate cancer patients. SBRT grew from the notion that high doses of radiation typical of brachytherapy could be delivered noninvasively using modern external-beam radiation therapy planning and delivery methods. SBRT is most commonly delivered using either a traditional gantry-mounted linear accelerator or a robotic arm-mounted linear accelerator. In this systematic review article, we compare and contrast the current clinical evidence supporting a gantry vs robotic arm SBRT for prostate cancer. The data for SBRT show encouraging and comparable results in terms of freedom from biochemical failure (>90% for low and intermediate risk at 5-7 years) and acute and late toxicity (<6% grade 3-4 late toxicities). Other outcomes (eg, overall and cancer-specific mortality) cannot be compared, given the indolent course of low-risk prostate cancer. At this time, neither SBRT device is recommended over the other for all patients; however, gantry-based SBRT machines have the abilities of treating larger volumes with conventional fractionation, shorter treatment time per fraction (~15 minutes for gantry vs ~45 minutes for robotic arm), and the ability to achieve better plans among obese patients (since they are able to use energies >6 MV). Finally, SBRT (particularly on a gantry) may also be more cost-effective than conventionally fractionated external-beam radiation therapy. Randomized controlled trials of SBRT using both technologies are underway. PMID:27574585

  14. Pulmonary Function Testing After Stereotactic Body Radiotherapy to the Lung

    SciTech Connect

    Bishawi, Muath; Kim, Bong; Moore, William H.; Bilfinger, Thomas V.

    2012-01-01

    Purpose: Surgical resection remains the standard of care for operable early-stage non-small-cell lung cancer (NSCLC). However, some patients are not fit for surgery because of comorbidites such as chronic obstructive pulmonary disease (COPD) and other medical conditions. We aimed to evaluate pulmonary function and tumor volume before and after stereotactic body radiotherapy (SBRT) for patients with and without COPD in early-stage lung cancer. Methods and Materials: A review of prospectively collected data of Stage I and II lung cancers, all treated with SBRT, was performed. The total SBRT treatment was 60 Gy administered in three 20 Gy fractions. The patients were analyzed based on their COPD status, using their pretreatment pulmonary function test cutoffs as established by the American Thoracic Society guidelines (forced expiratory volume [FEV]% {<=}50% predicted, FEV%/forced vital capacity [FVC]% {<=}70%). Changes in tumor volume were also assessed by computed tomography. Results: Of a total of 30 patients with Stage I and II lung cancer, there were 7 patients in the COPD group (4 men, 3 women), and 23 in t he No-COPD group (9 men, 14 women). At a mean follow-up time of 4 months, for the COPD and No-COPD patients, pretreatment and posttreatment FEV% was similar: 39 {+-} 5 vs. 40 {+-} 9 (p = 0.4) and 77 {+-} 0.5 vs. 73 {+-} 24 (p = 0.9), respectively. The diffusing capacity of the lungs for carbon monoxide (DL{sub CO}) did significantly increase for the No-COPD group after SBRT treatment: 60 {+-} 24 vs. 69 {+-} 22 (p = 0.022); however, DL{sub CO} was unchanged for the COPD group: 49 {+-} 13 vs. 50 {+-} 14 (p = 0.8). Although pretreatment tumor volume was comparable for both groups, tumor volume significantly shrank in the No-COPD group from 19 {+-} 24 to 9 {+-} 16 (p < 0.001), and there was a trend in the COPD patients from 12 {+-} 9 to 6 {+-} 5 (p = 0.06). Conclusion: SBRT did not seem to have an effect on FEV{sub 1} and FVC, but it shrank tumor volume and

  15. Adaptive Stereotactic Body Radiation Therapy Planning for Lung Cancer

    SciTech Connect

    Qin, Yujiao; Zhang, Fan; Yoo, David S.; Kelsey, Chris R.; Yin, Fang-Fang; Cai, Jing

    2013-09-01

    Purpose: To investigate the dosimetric effects of adaptive planning on lung stereotactic body radiation therapy (SBRT). Methods and Materials: Forty of 66 consecutive lung SBRT patients were selected for a retrospective adaptive planning study. CBCT images acquired at each fraction were used for treatment planning. Adaptive plans were created using the same planning parameters as the original CT-based plan, with the goal to achieve comparable comformality index (CI). For each patient, 2 cumulative plans, nonadaptive plan (P{sub NON}) and adaptive plan (P{sub ADP}), were generated and compared for the following organs-at-risks (OARs): cord, esophagus, chest wall, and the lungs. Dosimetric comparison was performed between P{sub NON} and P{sub ADP} for all 40 patients. Correlations were evaluated between changes in dosimetric metrics induced by adaptive planning and potential impacting factors, including tumor-to-OAR distances (d{sub T-OAR}), initial internal target volume (ITV{sub 1}), ITV change (ΔITV), and effective ITV diameter change (Δd{sub ITV}). Results: 34 (85%) patients showed ITV decrease and 6 (15%) patients showed ITV increase throughout the course of lung SBRT. Percentage ITV change ranged from −59.6% to 13.0%, with a mean (±SD) of −21.0% (±21.4%). On average of all patients, P{sub ADP} resulted in significantly (P=0 to .045) lower values for all dosimetric metrics. Δd{sub ITV}/d{sub T-OAR} was found to correlate with changes in dose to 5 cc (ΔD5cc) of esophagus (r=0.61) and dose to 30 cc (ΔD30cc) of chest wall (r=0.81). Stronger correlations between Δd{sub ITV}/d{sub T-OAR} and ΔD30cc of chest wall were discovered for peripheral (r=0.81) and central (r=0.84) tumors, respectively. Conclusions: Dosimetric effects of adaptive lung SBRT planning depend upon target volume changes and tumor-to-OAR distances. Adaptive lung SBRT can potentially reduce dose to adjacent OARs if patients present large tumor volume shrinkage during the treatment.

  16. Stereotactic Body Radiotherapy for Small Lung Tumors in the University of Tokyo Hospital

    PubMed Central

    Haga, Akihiro; Kida, Satoshi; Nakagawa, Keiichi

    2014-01-01

    Our work on stereotactic body radiation therapy (SBRT) for primary and metastatic lung tumors will be described. The eligibility criteria for SBRT, our previous SBRT method, the definition of target volume, heterogeneity correction, the position adjustment using four-dimensional cone-beam computed tomography (4D CBCT) immediately before SBRT, volumetric modulated arc therapy (VMAT) method for SBRT, verifying of tumor position within internal target volume (ITV) using in-treatment 4D-CBCT during VMAT-SBRT, shortening of treatment time using flattening-filter-free (FFF) techniques, delivery of 4D dose calculation for lung-VMAT patients using in-treatment CBCT and LINAC log data with agility multileaf collimator, and SBRT method for centrally located lung tumors in our institution will be shown. In our institution, these efforts have been made with the goal of raising the local control rate and decreasing adverse effects after SBRT. PMID:25110653

  17. Retreatment for prostate cancer with stereotactic body radiation therapy (SBRT): Feasible or foolhardy?

    PubMed

    Arcangeli, Stefano; Agolli, Linda; Donato, Vittorio

    2015-01-01

    The most popular therapeutic option in the management of radio-recurrent prostatic carcinoma is represented by the androgen deprivation therapy, that however should be considered only palliative and hampered by potential adverse effects of testosterone suppression. Local therapies such as surgery, cryoablation or brachytherapy might be curative choices for patients in good conditions and with a long-life expectancy, but at cost of significant risk of failure and severe toxicity. The administration of stereotactic body radiation therapy (SBRT) in this setting have come about because of tremendous technologic advances in image guidance and treatment delivery techniques that enable the delivery of large doses to tumor with reduced margins and high gradients outside the target, thereby reducing the volume of rectum which already received significant doses from primary radiotherapy. So far, very modest data are available to support its employment. Rationale, clinical experience, and challenges are herein reviewed and discussed. PMID:26696782

  18. Dose-Response Model for Chest Wall Tolerance of Stereotactic Body Radiation Therapy.

    PubMed

    Kimsey, Frank; McKay, Jesse; Gefter, Jeffrey; Milano, Michael T; Moiseenko, Vitali; Grimm, Jimm; Berg, Ronald

    2016-04-01

    Many recent studies have described rib fractures and chest wall pain following stereotactic body radiation therapy (SBRT). Although these toxicities generally are not life-threatening, the chest wall and ribs are considered dose-limiting tissues because of the potential effect on patients׳ quality of life. Few studies have reported dose-response models that can provide quantitative estimates of risk as a function of dose and volume. Notably, Memorial Sloan Kettering Cancer Center (Mutter et al(8)) analyzed grade 2 or higher chest wall toxicity in a cohort of 126 patients treated with linear accelerator-based SBRT; the authors provided detailed dose-volume histogram (DVH) data to allow for pooled analyses. We pooled these 126 patients with an additional 44 patients treated with CyberKnife at the Erlanger Medical Center to create an updated dose-response model for chest wall tolerance. In the aggregate analysis, the 10% risk level for grade 2 or higher complications for D70cc was 16.2Gy in 4 fractions, and the 50% risk level was D70cc = 65.1Gy in 4 fractions. For D2cc, the 10% and 50% risk levels in 4 fractions were 43.0Gy and 87.9Gy, respectively. These dose-tolerance limits may help quantify chest wall toxicity risks. Further research continues to determine more accurate estimates of grade 3 risk levels. PMID:27000509

  19. Management of Spinal Metastases From Renal Cell Carcinoma Using Stereotactic Body Radiotherapy

    SciTech Connect

    Nguyen, Quynh-Nhu; Shiu, Almon S.; Rhines, Laurence D.; Wang He; Allen, Pamela K.; Wang, Xin Shelley; Chang, Eric L.

    2010-03-15

    Purpose: To evaluate the outcomes associated with stereotactic body radiotherapy (SBRT) in the management of spinal metastases from renal cell carcinoma (RCC). Methods and Materials: SBRT was used in the treatment of patients with spinal metastases from RCC. Patients received either 24 Gy in a single fraction, 27 Gy in three fractions, or 30 Gy delivered in five fractions. Effectiveness of SBRT with respect to tumor control and palliation of pain was assessed using patient-reported outcomes. Results: A total of 48 patients with 55 spinal metastases were treated with SBRT with a median follow-up time of 13.1 months (range, 3.3-54.5 months). The actuarial 1-year spine tumor progression free survival was 82.1%. At pretreatment baseline, 23% patients were pain free; at 1 month and 12 months post-SBRT, 44% and 52% patients were pain free, respectively. No Grade 3-4 neurologic toxicity was observed. Conclusions: The data support SBRT as a safe and effective treatment modality that can be used to achieve good tumor control and palliation of pain associated with RCC spinal metastases. Further evaluation with randomized trials comparing SBRT to conventional radiotherapy may be warranted.

  20. Gas Chromatography-Quadrupole Time-of-Flight Mass Spectrometry-Based Determination of Isotopologue and Tandem Mass Isotopomer Fractions of Primary Metabolites for (13)C-Metabolic Flux Analysis.

    PubMed

    Mairinger, Teresa; Steiger, Matthias; Nocon, Justyna; Mattanovich, Diethard; Koellensperger, Gunda; Hann, Stephan

    2015-12-01

    For the first time an analytical work flow based on accurate mass gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOFMS) with chemical ionization for analysis providing a comprehensive picture of (13)C distribution along the primary metabolism is elaborated. The method provides a powerful new toolbox for (13)C-based metabolic flux analysis, which is an emerging strategy in metabolic engineering. In this field, stable isotope tracer experiments based on, for example, (13)C are central for providing characteristic patterns of labeled metabolites, which in turn give insights into the regulation of metabolic pathway kinetics. The new method enables the analysis of isotopologue fractions of 42 free intracellular metabolites within biotechnological samples, while tandem mass isotopomer information is also accessible for a large number of analytes. Hence, the method outperforms previous approaches in terms of metabolite coverage, while also providing rich isotopomer information for a significant number of key metabolites. Moreover, the established work flow includes novel evaluation routines correcting for isotope interference of naturally distributed elements, which is crucial following derivatization of metabolites. Method validation in terms of trueness, precision, and limits of detection was performed, showing excellent analytical figures of merit with an overall maximum bias of 5.8%, very high precision for isotopologue and tandem mass isotopomer fractions representing >10% of total abundance, and absolute limits of detection in the femtomole range. The suitability of the developed method is demonstrated on a flux experiment of Pichia pastoris employing two different tracers, i.e., 1,6(13)C2-glucose and uniformly labeled (13)C-glucose. PMID:26513365

  1. The use of RapidArc volumetric-modulated arc therapy to deliver stereotactic radiosurgery and stereotactic body radiotherapy to intracranial and extracranial targets

    SciTech Connect

    Roa, Dante E.; Schiffner, Daniel C.; Zhang Juying; Dietrich, Salam N.; Kuo, Jeffrey V.; Wong, Jason; Ramsinghani, Nilam S.; Al-Ghazi, Muthana S.A.L.

    2012-10-01

    Twenty-three targets in 16 patients treated with stereotactic radiosurgery (SRS) or stereotactic body radiotherapy (SBRT) were analyzed in terms of dosimetric homogeneity, target conformity, organ-at-risk (OAR) sparing, monitor unit (MU) usage, and beam-on time per fraction using RapidArc volumetric-modulated arc therapy (VMAT) vs. multifield sliding-window intensity-modulated radiation therapy (IMRT). Patients underwent computed tomography simulation with site-specific immobilization. Magnetic resonance imaging fusion and optical tracking were incorporated as clinically indicated. Treatment planning was performed using Eclipse v8.6 to generate sliding-window IMRT and 1-arc and 2-arc RapidArc plans. Dosimetric parameters used for target analysis were RTOG conformity index (CI{sub RTOG}), homogeneity index (HI{sub RTOG}), inverse Paddick Conformity Index (PCI), D{sub mean} and D5-D95. OAR sparing was analyzed in terms of D{sub max} and D{sub mean}. Treatment delivery was evaluated based on measured beam-on times delivered on a Varian Trilogy linear accelerator and recorded MU values. Dosimetric conformity, homogeneity, and OAR sparing were comparable between IMRT, 1-arc RapidArc and 2-arc RapidArc plans. Mean beam-on times {+-} SD for IMRT and 1-arc and 2-arc treatments were 10.5 {+-} 7.3, 2.6 {+-} 1.6, and 3.0 {+-} 1.1 minutes, respectively. Mean MUs were 3041, 1774, and 1676 for IMRT, 1-, and 2-arc plans, respectively. Although dosimetric conformity, homogeneity, and OAR sparing were similar between these techniques, SRS and SBRT fractions treated with RapidArc were delivered with substantially less beam-on time and fewer MUs than IMRT. The rapid delivery of SRS and SBRT with RapidArc improved workflow on the linac with these otherwise time-consuming treatments and limited the potential for intrafraction organ and patient motion, which can cause significant dosimetric errors. These clinically important advantages make image-guided RapidArc useful in the delivery

  2. Three-dimensional interactive and stereotactic human brain atlas of white matter tracts.

    PubMed

    Nowinski, Wieslaw L; Chua, Beng Choon; Yang, Guo Liang; Qian, Guo Yu

    2012-01-01

    We present a human brain atlas of white matter (WM) tracts containing 40 major tracts, which is three-dimensional (3D), segmented, labeled, interactive, stereotactic and correlated to structure and vasculature. We consider: (1) WM accuracy by correlating WM tracts to underlying neuroanatomy and quantifying them; (2) balance between realism and completeness by processing a sequence of track volumes generated for various parameters with the increasing track number to enable a tract "shape convergence". MPRAGE and DTI in 64 directions of the same subject were acquired on 3 Tesla. The method has three steps: DTI-MPRAGE registration, 3D tract generation from DTI, to WM reconstruction from MPRAGE to parcellation into 17 components. 82 track volumes were generated for a wide spectrum of parameter values: Fractional Anisotropy threshold in [0.0125, 0.55] and trajectory angle lower than 45°, 60°, 65°, 70°, 75°, 80°, 85°, 90°. For each tract, a sequence of track volumes was processed to create/edit contours delineating this tract to achieve its shape convergence. The parcellated tracts were grouped into commissures, associations, projections and posterior fossa tracts, and labeled following Terminologia Anatomica. To facilitate that, a dedicated tract editor is developed which processes multiple track volumes, handles tracts in three representations (tracks, contours, envelopes); provides editing/visualization simultaneously on axial, coronal, sagittal planes; enables tract labeling and coloring; and provides numerous tools (track counting, smoothing and length thresholding; representation conversion and saving; structural atlas support). A stereotactic tract atlas along with parcellated WM was developed to explore in real-time any individual tract or their groups along with surrounding neuroanatomy. PMID:21505883

  3. Clinical Outcome of Hypofractionated Stereotactic Radiotherapy for Abdominal Lymph Node Metastases

    SciTech Connect

    Bignardi, Mario; Navarria, Piera; Mancosu, Pietro; Cozzi, Luca; Fogliata, Antonella; Tozzi, Angelo; Castiglioni, Simona; Carnaghi, Carlo; Tronconi, Maria Chiara; Santoro, Armando; Scorsetti, Marta

    2011-11-01

    Purpose: We report the medium-term clinical outcome of hypofractionated stereotactic body radiotherapy (SBRT) in a series of patients with either a solitary metastasis or oligometastases from different tumors to abdominal lymph nodes. Methods and Materials: Between January 2006 and June 2009, 19 patients with unresectable nodal metastases in the abdominal retroperitoneal region were treated with SBRT. Of the patients, 11 had a solitary nodal metastasis and 8 had a dominant nodal lesion as part of oligometastatic disease, defined as up to five metastases. The dose prescription was 45 Gy to the clinical target volume in six fractions. The prescription had to be downscaled by 10% to 20% in 6 of 19 cases to keep within dose/volume constraints. The first 11 patients were treated with three-dimensional conformal techniques and the last 8 by volumetric intensity-modulated arc therapy. Median follow-up was 1 year. Results: Of 19 patients, 2 had a local progression at the site of SBRT; both also showed concomitant tumor growth at distant sites. The actuarial rate of freedom from local progression was 77.8% {+-} 13.9% at both 12 and 24 months. Eleven patients showed progressive local and/or distant disease at follow-up. The 12- and 24-month progression-free survival rates were 29.5% {+-} 13.4% and 19.7% {+-} 12.0%, respectively. The number of metastases (solitary vs. nonsolitary oligometastases) emerged as the only significant variable affecting progression-free survival (p < 0.0004). Both acute and chronic toxicities were minimal. Conclusions: Stereotactic body radiotherapy for metastases to abdominal lymph nodes was shown to be feasible with good clinical results in terms of medium-term local control and toxicity rates. Even if most patients eventually show progressive disease at other sites, local control achieved by SBRT may be potentially significant for preserving quality of life and delaying further chemotherapy.

  4. Excellent Local Control With Stereotactic Radiotherapy Boost After External Beam Radiotherapy in Patients With Nasopharyngeal Carcinoma

    SciTech Connect

    Hara, Wendy; Loo, Billy W.; Goffinet, Don R.; Chang, Steven D.; Adler, John R.; Pinto, Harlan A.; Fee, Willard E.; Kaplan, Michael J.; Fischbein, Nancy J.; Le, Quynh-Thu

    2008-06-01

    Purpose: To determine long-term outcomes in patients receiving stereotactic radiotherapy (SRT) as a boost after external beam radiotherapy (EBRT) for locally advanced nasopharyngeal carcinoma (NPC). Methods and Materials: Eight-two patients received an SRT boost after EBRT between September 1992 and July 2006. Nine patients had T1, 30 had T2, 12 had T3, and 31 had T4 tumors. Sixteen patients had Stage II, 19 had Stage III, and 47 had Stage IV disease. Patients received 66 Gy of EBRT followed by a single-fraction SRT boost of 7-15 Gy, delivered 2-6 weeks after EBRT. Seventy patients also received cisplatin-based chemotherapy delivered concurrently with and adjuvant to radiotherapy. Results: At a median follow-up of 40.7 months (range, 6.5-144.2 months) for living patients, there was only 1 local failure in a patient with a T4 tumor. At 5 years, the freedom from local relapse rate was 98%, freedom from nodal relapse 83%, freedom from distant metastasis 68%, freedom from any relapse 67%, and overall survival 69%. Late toxicity included radiation-related retinopathy in 3, carotid aneurysm in 1, and radiographic temporal lobe necrosis in 10 patients, of whom 2 patients were symptomatic with seizures. Of 10 patients with temporal lobe necrosis, 9 had T4 tumors. Conclusion: Stereotactic radiotherapy boost after EBRT provides excellent local control for patients with NPC. Improved target delineation and dose homogeneity of radiation delivery for both EBRT and SRT is important to avoid long-term complications. Better systemic therapies for distant control are needed.

  5. Target Coverage in Image-Guided Stereotactic Body Radiotherapy of Liver Tumors

    SciTech Connect

    Wunderink, Wouter . E-mail: w.wunderink@erasmusmc.nl; Romero, Alejandra Mendez; Osorio, Eliana M. Vasquez; Boer, Hans C.J. de; Brandwijk, Rene P.; Levendag, Peter C.; Heijmen, Ben

    2007-05-01

    Purpose: To determine the effect of image-guided procedures (with computed tomography [CT] and electronic portal images before each treatment fraction) on target coverage in stereotactic body radiotherapy for liver patients using a stereotactic body frame (SBF) and abdominal compression. CT guidance was used to correct for day-to-day variations in the tumor's mean position in the SBF. Methods and Materials: By retrospectively evaluating 57 treatment sessions, tumor coverage, as obtained with the clinically applied CT-guided protocol, was compared with that of alternative procedures. The internal target volume-plus (ITV{sup +}) was introduced to explicitly include uncertainties in tumor delineations resulting from CT-imaging artifacts caused by residual respiratory motion. Tumor coverage was defined as the volume overlap of the ITV{sup +}, derived from a tumor delineated in a treatment CT scan, and the planning target volume. Patient stability in the SBF, after acquisition of the treatment CT scan, was evaluated by measuring the displacement of the bony anatomy in the electronic portal images relative to CT. Results: Application of our clinical protocol (with setup corrections following from manual measurements of the distances between the contours of the planning target volume and the daily clinical target volume in three orthogonal planes, multiple two-dimensional) increased the frequency of nearly full ({>=}99%) ITV{sup +} coverage to 77% compared with 63% without setup correction. An automated three-dimensional method further improved the frequency to 96%. Patient displacements in the SBF were generally small ({<=}2 mm, 1 standard deviation), but large craniocaudal displacements (maximal 7.2 mm) were occasionally observed. Conclusion: Daily, CT-assisted patient setup may substantially improve tumor coverage, especially with the automated three-dimensional procedure. In the present treatment design, patient stability in the SBF should be verified with portal

  6. Respiratory Gating during Stereotactic Body Radiotherapy for Lung Cancer Reduces Tumor Position Variability

    PubMed Central

    Saito, Tetsuo; Matsuyama, Tomohiko; Toya, Ryo; Fukugawa, Yoshiyuki; Toyofuku, Takamasa; Semba, Akiko; Oya, Natsuo

    2014-01-01

    Purpose We evaluated the effects of respiratory gating on treatment accuracy in lung cancer patients undergoing lung stereotactic body radiotherapy by using electronic portal imaging device (EPID) images. Materials and Methods Our study population consisted of 30 lung cancer patients treated with stereotactic body radiotherapy (48 Gy/4 fractions/4 to 9 days). Of these, 14 were treated with- (group A) and 16 without gating (group B); typically the patients whose tumors showed three-dimensional respiratory motion ≧5 mm were selected for gating. Tumor respiratory motion was estimated using four-dimensional computed tomography images acquired during treatment simulation. Tumor position variability during all treatment sessions was assessed by measuring the standard deviation (SD) and range of tumor displacement on EPID images. The two groups were compared for tumor respiratory motion and position variability using the Mann-Whitney U test. Results The median three-dimensional tumor motion during simulation was greater in group A than group B (9 mm, range 3–30 mm vs. 2 mm, range 0–4 mm; p<0.001). In groups A and B the median SD of the tumor position was 1.1 mm and 0.9 mm in the craniocaudal- (p = 0.24) and 0.7 mm and 0.6 mm in the mediolateral direction (p = 0.89), respectively. The median range of the tumor position was 4.0 mm and 3.0 mm in the craniocaudal- (p = 0.21) and 2.0 mm and 1.5 mm in the mediolateral direction (p = 0.20), respectively. Conclusions Although patients treated with respiratory gating exhibited greater respiratory tumor motion during treatment simulation, tumor position variability in the EPID images was low and comparable to patients treated without gating. This demonstrates the benefit of respiratory gating. PMID:25379729

  7. Combined Effects of Embolization and Hypofractionated Conformal Stereotactic Radiotherapy in Arteriovenous Malformations of the Brain

    PubMed Central

    Lindvall, P.; Wikholm, G.; Bergström, P.; Löfroth, P.; Bergenheim, A.T.

    2005-01-01

    Summary There are three major treatment options for cerebral AVMs; surgery, embolization and radiosurgery. Embolization may be effective to reduce the size and density but completely obliterates AVMs only in a minority of cases. Radiosurgery may be an alternative to resection, especially in smaller AVMs. Large AVMs have been considered difficult to treat safely and effectively with single fraction radiosurgery. Hypofractionated conformal stereotactic radiotherapy (HCSRT) alone or in combination with embolization may be an alternative treatment. Embolization may reduce the volume and density of AVMs, followed by HCSRT, allowing a safe delivery of a higher total dose of radiation than possible with a single fraction. Sixteen patients with AVMs were treated with embolization and HCSRT. Embolization was performed in 1-6 (median 2) sessions. HCSRT was delivered in 5 fractions with 6-7 Gy each to the total dose of 30-35 Gy. Cerebral angiographies before and after embolization were digitally compared for calculation of volume reduction and luminescence as a measure of AVM density. The mean AVM volume in 15 patients was reduced from 11.9 ± 2.1 (1-29, median 10.0) ml to 6.5 ± 2.0 (0.5-28, median 3) ml by embolization. The luminescence for all AVMs was significantly higher after than before embolization, indicating that all AVMs were less dense after embolization. Thirteen out of 16 patients (13/16, 81%) treated with embolization and HCSRT have so far shown obliteration of their AVMs 2-9 (median 4) years after HCSRT. Three patients experienced neurological sequele after embolization, and three patients developed radionecrosis after HCSRT. Using a new method to compare cerebral angiographies in AVMs we report reduction in density and volume after embolization. The obliteration rate of a combined treatment with embolization and HCSRT seems comparable with single fraction radiosurgery although the AVMs in our series are larger than reported in most series treated with single

  8. Probabilities of Radiation Myelopathy Specific to Stereotactic Body Radiation Therapy to Guide Safe Practice

    SciTech Connect

    Sahgal, Arjun; Weinberg, Vivian; Ma, Lijun; Chang, Eric; Chao, Sam; Muacevic, Alexander; Gorgulho, Alessandra; Soltys, Scott; Gerszten, Peter C.; Ryu, Sam; Angelov, Lilyana; Gibbs, Iris; Wong, C. Shun; Larson, David A.

    2013-02-01

    Purpose: Dose-volume histogram (DVH) results for 9 cases of post spine stereotactic body radiation therapy (SBRT) radiation myelopathy (RM) are reported and compared with a cohort of 66 spine SBRT patients without RM. Methods and Materials: DVH data were centrally analyzed according to the thecal sac point maximum (Pmax) volume, 0.1- to 1-cc volumes in increments of 0.1 cc, and to the 2 cc volume. 2-Gy biologically equivalent doses (nBED) were calculated using an {alpha}/{beta} = 2 Gy (units = Gy{sub 2/2}). For the 2 cohorts, the nBED means and distributions were compared using the t test and Mann-Whitney test, respectively. Significance (P<.05) was defined as concordance of both tests at each specified volume. A logistic regression model was developed to estimate the probability of RM using the dose distribution for a given volume. Results: Significant differences in both the means and distributions at the Pmax and up to the 0.8-cc volume were observed. Concordant significance was greatest for the Pmax volume. At the Pmax volume the fit of the logistic regression model, summarized by the area under the curve, was 0.87. A risk of RM of 5% or less was observed when limiting the thecal sac Pmax volume doses to 12.4 Gy in a single fraction, 17.0 Gy in 2 fractions, 20.3 Gy in 3 fractions, 23.0 Gy in 4 fractions, and 25.3 Gy in 5 fractions. Conclusion: We report the first logistic regression model yielding estimates for the probability of human RM specific to SBRT.

  9. Lung Density Changes After Stereotactic Radiotherapy: A Quantitative Analysis in 50 Patients

    SciTech Connect

    Palma, David A.; Soernsen de Koste, John van; Verbakel, Wilko F.A.R.; Vincent, Andrew; Senan, Suresh

    2011-11-15

    Purpose: Radiologic lung density changes are observed in more than 50% of patients after stereotactic body radiotherapy (SBRT) for lung cancer. We studied the relationship between SBRT dose and posttreatment computed tomography (CT) density changes, a surrogate for lung injury. Methods and Materials: The SBRT fractionation schemes used to treat Stage I lung cancer with RapidArc were three fractions of 18 Gy, five fractions of 11 Gy, or eight fractions of 7.5 Gy, prescribed at the 80% isodose. Follow-up CT scans performed at less than 6 months (n = 50) and between 6 and 9 months (n = 30) after SBRT were reviewed. Posttreatment scans were coregistered with baseline scans using a B-spline deformable registration algorithm. Voxel-Hounsfield unit histograms were created for doses between 0.5 and 50 Gy. Linear mixed effects models were used to assess the effects of SBRT dose on CT density, and the influence of possible confounders was tested. Results: Increased CT density was associated with higher dose, increasing planning target volume size, and increasing time after SBRT (all p < 0.0001). Density increases were apparent in areas receiving >6 Gy, were most prominent in areas receiving >20 Gy, and seemed to plateau above 40 Gy. In regions receiving >36 Gy, the reduction in air-filled fraction of lung after treatment was up to 18%. No increase in CT density was observed in the contralateral lung receiving {>=}3 Gy. Conclusions: A dose-response relationship exists for quantitative CT density changes after SBRT. A threshold of effect is seen at low doses, and a plateau at highest doses.

  10. soil organic matter fractionation

    NASA Astrophysics Data System (ADS)

    Osat, Maryam; Heidari, Ahmad

    2010-05-01

    Carbon is essential for plant growth, due to its effects on other soil properties like aggregation. Knowledge of dynamics of organic matter in different locations in the soil matrix can provide valuable information which affects carbon sequestration and soil the other soil properties. Extraction of soil organic matter (SOM) fractions has been a long standing approach to elucidating the roles of soil organic matter in soil processes. Several kind fractionation methods are used and all provide information on soil organic matter function. Physical fractionation capture the effects on SOM dynamics of the spatial arrangement of primary and secondary organomineral particles in soil while chemical fractionation can not consider the spatial arrangement but their organic fractions are suitable for advanced chemical characterization. Three method of physical separation of soil have been used, sieving, sedimentation and densitometry. The distribution of organic matter within physical fractions of the soil can be assessed by sieving. Sieving separates soil particles based strictly on size. The study area is located on north central Iran, between 35° 41'- 36° 01' N and 50° 42'- 51° 14' E. Mean annual precipitation about 243.8 mm and mean annual air temperature is about 14.95 °C. The soil moisture and temperature regime vary between aridic-thermic in lower altitudes to xeric-mesic in upper altitudes. More than 36 surface soil samples (0-20 cm) were collected according to land-use map units. After preliminary analyzing of samples 10 samples were selected for further analyses in five size fractions and three different time intervals in September, January and April 2008. Fractionation carried out by dry sieving in five classes, 1-2 mm, 0.5-1 mm, 270 μm-0.5mm, 53-270 μm and <53 μm. Organic matter and C/N ratio were determined for all fractions at different time intervals. Chemical fractionation of organic matter also carried out according to Tan (2003), also Mineralogical

  11. Medical physics aspects of the synchrotron radiation therapies: Microbeam radiation therapy (MRT) and synchrotron stereotactic radiotherapy (SSRT).

    PubMed

    Bräuer-Krisch, Elke; Adam, Jean-Francois; Alagoz, Enver; Bartzsch, Stefan; Crosbie, Jeff; DeWagter, Carlos; Dipuglia, Andrew; Donzelli, Mattia; Doran, Simon; Fournier, Pauline; Kalef-Ezra, John; Kock, Angela; Lerch, Michael; McErlean, Ciara; Oelfke, Uwe; Olko, Pawel; Petasecca, Marco; Povoli, Marco; Rosenfeld, Anatoly; Siegbahn, Erik A; Sporea, Dan; Stugu, Bjarne

    2015-09-01

    Stereotactic Synchrotron Radiotherapy (SSRT) and Microbeam Radiation Therapy (MRT) are both novel approaches to treat brain tumor and potentially other tumors using synchrotron radiation. Although the techniques differ by their principles, SSRT and MRT share certain common aspects with the possibility of combining their advantages in the future. For MRT, the technique uses highly collimated, quasi-parallel arrays of X-ray microbeams between 50 and 600 keV. Important features of highly brilliant Synchrotron sources are a very small beam divergence and an extremely high dose rate. The minimal beam divergence allows the insertion of so called Multi Slit Collimators (MSC) to produce spatially fractionated beams of typically ∼25-75 micron-wide microplanar beams separated by wider (100-400 microns center-to-center(ctc)) spaces with a very sharp penumbra. Peak entrance doses of several hundreds of Gy are extremely well tolerated by normal tissues and at the same time provide a higher therapeutic index for various tumor models in rodents. The hypothesis of a selective radio-vulnerability of the tumor vasculature versus normal blood vessels by MRT was recently more solidified. SSRT (Synchrotron Stereotactic Radiotherapy) is based on a local drug uptake of high-Z elements in tumors followed by stereotactic irradiation with 80 keV photons to enhance the dose deposition only within the tumor. With SSRT already in its clinical trial stage at the ESRF, most medical physics problems are already solved and the implemented solutions are briefly described, while the medical physics aspects in MRT will be discussed in more detail in this paper. PMID:26043881

  12. Stereotactic body radiation therapy of early-stage non-small-cell lung carcinoma: Phase I study

    SciTech Connect

    McGarry, Ronald C. . E-mail: rmcgarry@iupui.edu; Papiez, Lech; Williams, Mark; Whitford, Tia; Timmerman, Robert D.

    2005-11-15

    Purpose: A Phase I dose escalation study of stereotactic body radiation therapy to assess toxicity and local control rates for patients with medically inoperable Stage I lung cancer. Methods and Materials: All patients had non-small-cell lung carcinoma, Stage T1a or T1b N0, M0. Patients were immobilized in a stereotactic body frame and treated in escalating doses of radiotherapy beginning at 24 Gy total (3 x 8 Gy fractions) using 7-10 beams. Cohorts were dose escalated by 6.0 Gy total with appropriate observation periods. Results: The maximum tolerated dose was not achieved in the T1 stratum (maximum dose = 60 Gy), but within the T2 stratum, the maximum tolerated dose was realized at 72 Gy for tumors larger than 5 cm. Dose-limiting toxicity included predominantly bronchitis, pericardial effusion, hypoxia, and pneumonitis. Local failure occurred in 4/19 T1 and 6/28 T2 patients. Nine local failures occurred at doses {<=}16 Gy and only 1 at higher doses. Local failures occurred between 3 and 31 months from treatment. Within the T1 group, 5 patients had distant or regional recurrence as an isolated event, whereas 3 patients had both distant and regional recurrence. Within the T2 group, 2 patients had solitary regional recurrences, and the 4 patients who failed distantly also failed regionally. Conclusions: Stereotactic body radiation therapy seems to be a safe, effective means of treating early-stage lung cancer in medically inoperable patients. Excellent local control was achieved at higher dose cohorts with apparent dose-limiting toxicities in patients with larger tumors.

  13. Stereotactic body radiation therapy for prostate cancer patients with old age or medical comorbidity: a 5-year follow-up of an investigational study.

    PubMed

    Lee, Sea-Won; Jang, Hong Seok; Lee, Jong Hoon; Kim, Sung Hwan; Yoon, Sei Chul

    2014-12-01

    We evaluated 5-year follow-up of stereotactic body radiation therapy (SBRT) with Cyberknife for prostate cancer patients. Forty-five men with prostate adenocarcinoma who received SBRT using Cyberknife from May 2006 to November 2012 were enrolled in this study. They were prostate cancer patients with old age and medical comorbidities who received a total of 36 Gy to the prostate in 5 fractions with either everyday or every other day schedule. Prostate-specific antigen (PSA) levels at initial diagnosis and after radiation were traced. Primary endpoints were biochemical relapse-free survival (bRFS), progression-free survival (PFS), and overall survival (OS). The definition of biochemical relapse was a PSA level of nadir+2 ng/mL. Progression was defined as biochemically or clinically detected disease and the start of salvage therapy. After median follow-up of 63 months, the 5-year bRFS for all patients was estimated at 89.7%. The 5-year PFS was estimated at 71%. Four cases of biochemical relapse were observed, including two patients who experienced locoregional failure and one patient who had distant metastasis with biochemical relapse. The 5-year OS was estimated at 94.3%. There were five deaths, all of which were unrelated to prostate cancer. There was no grade 3 or higher acute complication. Grade 3 or higher late urinary toxicity was reported in 2 (4.4%) of 45 patients. The 5-year survival and toxicity outcome of SBRT using Cyberknife on prostate cancer patients with old age or comorbidities were favorable and safe in an investigational study. PMID:25526468

  14. Incidence and Predictive Factors of Pain Flare After Spine Stereotactic Body Radiation Therapy: Secondary Analysis of Phase 1/2 Trials

    SciTech Connect

    Pan, Hubert Y.; Allen, Pamela K.; Wang, Xin S.; Chang, Eric L.; Rhines, Laurence D.; Tatsui, Claudio E.; Amini, Behrang; Wang, Xin A.; Tannir, Nizar M.; Brown, Paul D.; Ghia, Amol J.

    2014-11-15

    Purpose/Objective(s): To perform a secondary analysis of institutional prospective spine stereotactic body radiation therapy (SBRT) trials to investigate posttreatment acute pain flare. Methods and Materials: Medical records for enrolled patients were reviewed. Study protocol included baseline and follow-up surveys with pain assessment by Brief Pain Inventory and documentation of pain medications. Patients were considered evaluable for pain flare if clinical note or follow-up survey was completed within 2 weeks of SBRT. Pain flare was defined as a clinical note indicating increased pain at the treated site or survey showing a 2-point increase in worst pain score, a 25% increase in analgesic intake, or the initiation of steroids. Binary logistic regression was used to determine predictive factors for pain flare occurrence. Results: Of the 210 enrolled patients, 195 (93%) were evaluable for pain flare, including 172 (88%) clinically, 135 (69%) by survey, and 112 (57%) by both methods. Of evaluable patients, 61 (31%) had undergone prior surgery, 57 (29%) had received prior radiation, and 34 (17%) took steroids during treatment, mostly for prior conditions. Pain flare was observed in 44 patients (23%). Median time to pain flare was 5 days (range, 0-20 days) after the start of treatment. On multivariate analysis, the only independent factor associated with pain flare was the number of treatment fractions (odds ratio = 0.66, P=.004). Age, sex, performance status, spine location, number of treated vertebrae, prior radiation, prior surgery, primary tumor histology, baseline pain score, and steroid use were not significant. Conclusions: Acute pain flare after spine SBRT is a relatively common event, for which patients should be counseled. Additional study is needed to determine whether prophylactic or symptomatic intervention is preferred.

  15. Prognostic impact of average iodine density assessed by dual-energy spectral imaging for predicting lung tumor recurrence after stereotactic body radiotherapy.

    PubMed

    Aoki, Masahiko; Hirose, Katsumi; Sato, Mariko; Akimoto, Hiroyoshi; Kawaguchi, Hideo; Hatayama, Yoshiomi; Fujioka, Ichitaro; Tanaka, Mitsuki; Ono, Shuichi; Takai, Yoshihiro

    2016-07-01

    The purpose of this study was to investigate the prognostic significance of average iodine density as assessed by dual-energy computed tomography (DE-CT) for lung tumors treated with stereotactic body radiotherapy (SBRT). From March 2011 to August 2014, 93 medically inoperable patients with 74 primary lung cancers and 19 lung metastases underwent DE-CT prior to SBRT of a total dose of 45-60 Gy in 5-10 fractions. Of these 93 patients, nine patients had two lung tumors. Thus, 102 lung tumors were included in this study. DE-CT was performed for pretreatment evaluation. Regions of interest were set for the entire tumor, and average iodine density was obtained using a dedicated imaging software and evaluated with regard to local control. The median follow-up period was 23.4 months (range, 1.5-54.5 months). The median value of the average iodine density was 1.86 mg/cm(3) (range, 0.40-9.27 mg/cm(3)). Two-year local control rates for the high and low average iodine density groups divided by the median value of the average iodine density were 96.9% and 75.7% (P = 0.006), respectively. Tumors with lower average iodine density showed a worse prognosis, possibly reflecting a hypoxic cell population in the tumor. The average iodine density exhibited a significant impact on local control. Our preliminary results indicate that iodine density evaluated using dual-energy spectral CT may be a useful, noninvasive and quantitative assessment of radio-resistance caused by presumably hypoxic cell populations in tumors. PMID:26826198

  16. Prognostic impact of average iodine density assessed by dual-energy spectral imaging for predicting lung tumor recurrence after stereotactic body radiotherapy

    PubMed Central

    Aoki, Masahiko; Hirose, Katsumi; Sato, Mariko; Akimoto, Hiroyoshi; Kawaguchi, Hideo; Hatayama, Yoshiomi; Fujioka, Ichitaro; Tanaka, Mitsuki; Ono, Shuichi; Takai, Yoshihiro

    2016-01-01

    The purpose of this study was to investigate the prognostic significance of average iodine density as assessed by dual-energy computed tomography (DE-CT) for lung tumors treated with stereotactic body radiotherapy (SBRT). From March 2011 to August 2014, 93 medically inoperable patients with 74 primary lung cancers and 19 lung metastases underwent DE-CT prior to SBRT of a total dose of 45–60 Gy in 5–10 fractions. Of these 93 patients, nine patients had two lung tumors. Thus, 102 lung tumors were included in this study. DE-CT was performed for pretreatment evaluation. Regions of interest were set for the entire tumor, and average iodine density was obtained using a dedicated imaging software and evaluated with regard to local control. The median follow-up period was 23.4 months (range, 1.5–54.5 months). The median value of the average iodine density was 1.86 mg/cm3 (range, 0.40–9.27 mg/cm3). Two-year local control rates for the high and low average iodine density groups divided by the median value of the average iodine density were 96.9% and 75.7% (P = 0.006), respectively. Tumors with lower average iodine density showed a worse prognosis, possibly reflecting a hypoxic cell population in the tumor. The average iodine density exhibited a significant impact on local control. Our preliminary results indicate that iodine density evaluated using dual-energy spectral CT may be a useful, noninvasive and quantitative assessment of radio-resistance caused by presumably hypoxic cell populations in tumors. PMID:26826198

  17. 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.

  18. OP09STEREOTACTIC RADIOSURGERY FOR BRAIN METASTASES AT THE CHRISTIE AT SALFORD ROYAL HOSPITAL: OUR TWO-YEAR EXPERIENCE

    PubMed Central

    Helbrow, J.; McBain, C.; Gattamaneni, R.; Tran, A.; McCarthy, C.; Edwards, R.; Redikin, J.; Handley, J.; O'Hara, C.; Kennedy, J.; Mills, S.; Soh, C.; Leggate, J.; Whitfield, G.

    2014-01-01

    INTRODUCTION: Stereotactic radiosurgery (SRS) for brain metastases (BMs) commenced at The Christie at Salford in Dec 11 using the Novalis TxTM and BrainLab ExacTrac® system. We report our first 2 years' data. METHOD: Patients meeting NHS commissioning criteria were referred via MDT for assessment and if suitable consent. We used the BrainLab mask, CT and MRI. Gross tumour volumes (GTVs) were grown by 2mm if <4cm3 and by 1mm if >4cm3 to a planning target volume. The dose to the 80% isodose was 21Gy/1 fraction(#), 18Gy/1# and 25.5Gy/3# alternate days for PTVs <7cm3, 7-13cm3 and >13cm3 respectively and 30Gy/5# on alternate days to the 90% isodose in critical locations or where organ at risk constraints were exceeded. Follow up was 3-monthly with MRI and clinic review. Radiological response was classified as complete, unequivocal, enlargement consistent with treatment, enlargement suspicious of progression or unequivocal progression. RESULTS: Between Dec 11-Jan 14, 89 patients were consented, 51% female. Median age was 61 years (range 16-81). Primaries included lung (34%), breast (22%) and melanoma (15%), which was controlled in 67%; 42% had no extracranial metastases. A total of 170 BMs were treated (1 a retreat); per course a median of 2 (1-5) BMs were treated with median total GTV 4.87cm3 (0.05-29.9cm3). Prescribed dose was 21Gy/1# in 101 BMs, 18Gy/1# in 43, 25.5Gy/3# in 10 and 30Gy/5# in 16. One year survival from first SRS was: overall 48% (95% CI 34%-60%), lung 39% (18%-59%), breast 89% (62%-97%) and melanoma 44% (10%-75%). CONCLUSION: Overall survival results are encouraging and suggest appropriate patient selection. More detailed analysis including toxicity and time to intracranial progression will be presented.

  19. Outcomes of Stereotactic Ablative Radiotherapy in Patients With Potentially Operable Stage I Non-Small Cell Lung Cancer

    SciTech Connect

    Lagerwaard, Frank J.; Verstegen, Naomi E.; Haasbeek, Cornelis J.A.; Slotman, Ben J.; Paul, Marinus A.; Smit, Egbert F.; Senan, Suresh

    2012-05-01

    Background: Approximately two-thirds of patients with early-stage non-small-cell lung cancer (NSCLC) in The Netherlands currently undergo surgical resection. As an increasing number of fit patients have elected to undergo stereotactic ablative radiotherapy (SABR) in recent years, we studied outcomes after SABR in patients with potentially operable stage I NSCLC. Methods and Materials: In an institutional prospective database collected since 2003, 25% of lung SABR cases (n = 177 patients) were found to be potentially operable when the following patients were excluded: those with (1) synchronous lung tumors or other malignancy, (2) prior high-dose radiotherapy/pneumonectomy, (3) chronic obstructive pulmonary disease with a severity score of 3-4 according to the Global initiative for Obstructive Lung Disease classification. (4) a performance score of {>=}3, and (5) other comorbidity precluding surgery. Study patients included 101 males and 76 females, with a median age of 76 years old, 60% of whom were staged as T1 and 40% of whom were T2. Median Charlson comorbidity score was 2 (range, 0-5). A SABR dose of 60 Gy was delivered using a risk-adapted scheme in 3, 5, or 8 fractions, depending on tumor size and location. Follow-up chest computed tomography scans were obtained at 3, 6, and 12 months and yearly thereafter. Results: Median follow-up was 31.5 months; and median overall survival (OS) was 61.5 months, with 1- and 3-year survival rates of 94.7% and 84.7%, respectively. OS rates at 3 years in patients with (n = 59) and without (n = 118) histological diagnosis did not differ significantly (96% versus 81%, respectively, p = 0.39). Post-SABR 30-day mortality was 0%, while predicted 30-day mortality for a lobectomy, derived using the Thoracoscore predictive model (Falcoz PE et al. J Thorac Cardiovasc Surg 2007;133:325-332), would have been 2.6%. Local control rates at 1 and 3 years were 98% and 93%, respectively. Regional and distant failure rates at 3 years were each

  20. Anti-PD-1 Blockade and Stereotactic Radiation Produce Long-Term Survival in Mice With Intracranial Gliomas

    SciTech Connect

    Zeng, Jing; See, Alfred P.; Phallen, Jillian; Jackson, Christopher M.; Belcaid, Zineb; Ruzevick, Jacob; Durham, Nicholas; Meyer, Christian; Harris, Timothy J.; Albesiano, Emilia; Pradilla, Gustavo; Ford, Eric; Wong, John; Hammers, Hans-Joerg; Mathios, Dimitris; Tyler, Betty; Brem, Henry; Tran, Phuoc T.; Pardoll, Drew; Drake, Charles G.; and others

    2013-06-01

    Purpose: Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults, and radiation is one of the main treatment modalities. However, cure rates remain low despite best available therapies. Immunotherapy is a promising modality that could work synergistically with radiation, which has been shown to increase antigen presentation and promote a proinflammatory tumor microenvironment. Programmed-death-1 (PD-1) is a surface receptor expressed on activated and exhausted T cells, which mediate T cell inhibition upon binding with its ligand PD-L1, expressed on many tumor types including human GBMs. We tested the combination of anti-PD-1 immunotherapy with stereotactic radiosurgery in a mouse orthotopic GBM model. Methods and Materials: We performed intracranial implantation of mouse glioma cell line GL261 transfected with luciferase into C57BL/6 mice. Mice were stratified into 4 treatment groups: (1) control; (2) radiation only; (3) anti-PD-1 antibody only; and (4) radiation plus anti-PD-1 antibody. Overall survival was quantified. The mice were killed on day 21 after implantation to assess immunologic parameters in the brain/tumor, cervical lymph nodes, and spleen. Results: Improved survival was demonstrated with combination anti-PD-1 therapy plus radiation compared with either modality alone: median survival was 25 days in the control arm, 27 days in the anti-PD-1 antibody arm, 28 days in the radiation arm, and 53 days in the radiation plus anti-PD-1 therapy arm (P<.05 by log-rank Mantle-Cox). Long-term survival was seen only in the combined treatment arm, with a fraction (15%-40%) of animals alive at day 180+ after treatment. Immunologic data on day 21 after implantation showed increased tumor infiltration by cytotoxic T cells (CD8+/interferon-γ+/tumor necrosis factor-α+) and decreased regulatory T cells (CD4+/FOXP3) in the combined treatment group compared with the single modality arms. Conclusions: The combination of PD-1 blockade and localized

  1. Stereotactic PET atlas of the human brain: Aid for visual interpretation of functional brain images

    SciTech Connect

    Minoshima, S.; Koeppe, R.A.; Frey, A.; Ishihara, M.; Kuhl, D.E.

    1994-06-01

    In the routine analysis of functional brain images obtained by PET, subjective visual interpretation is often used for anatomic localization. To enhance the accuracy and consistency of the anatomic interpretation, a PET stereotactic atlas and localization approach was designed for functional brain images. The PET atlas was constructed from a high-resolution [{sup 18}F]fluorodeoxyglucose (FDG) image set of a normal volunteer (a 41-yr-ld woman). The image set was reoriented stereotactically, according to the intercommissural (anterior and posterior commissures) line and transformed to the standard stereotactic atlas coordinates. Cerebral structures were annotated on the transaxial planes using a proportional grid system and surface-rendered images. The stereotactic localization technique was applied to image sets from patients with Alzheimer`s disease, and areas of functional alteration were localized visually by referring to the PET atlas. Major brain structures were identified on both transaxial planes and surface-rendered images. In the stereotactic system, anatomic correspondence between the PET atlas and stereotactically reoriented individual image sets of patients with Alzheimer`s disease facilitated both indirect and direct localization of the cerebral structures. Because rapid stereotactic alignment methods for PET images are now available for routine use, the PET atlas will serve as an aid for visual interpretation of functional brain images in the stereotactic system. Widespread application of stereotactic localization may be used in functional brain images, not only in the research setting, but also in routine clinical situations. 41 refs., 3 figs.

  2. Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer Tumors Greater Than 5 cm: Safety and Efficacy

    SciTech Connect

    Woody, Neil M. Stephans, Kevin L.; Marwaha, Gaurav; Djemil, Toufik; Videtic, Gregory M.M.

    2015-06-01

    Purpose: The purpose of this study was to determine outcomes of patients with node-negative medically inoperable non-small cell lung cancer (NSCLC) whose primary tumors exceeded 5 cm and were treated with stereotactic body radiation therapy (SBRT). Methods and Materials: We surveyed our institutional prospective lung SBRT registry to identify treated patients with tumors >5 cm. Treatment outcomes for local control (LC), locoregional control (LRC), disease-free survival (DFS), and overall survival (OS) were assessed by Kaplan-Meier estimates. Toxicities were graded according to Common Terminology Criteria for Adverse Events version 4. Mean pretreatment pulmonary function test values were compared to mean posttreatment values. Results: From December 2003 to July 2014, 40 patients met study criteria. Median follow-up was 10.8 months (range: 0.4-70.3 months). Median age was 76 years (range: 56-90 years), median body mass index was 24.3 (range: 17.7-37.2), median Karnofsky performance score was 80 (range: 60-90), and median Charlson comorbidity index score was 2 (range: 0-5). Median forced expiratory volume in 1 second (FEV1) was 1.41 L (range: 0.47-3.67 L), and median diffusion capacity (DLCO) was 47% of predicted (range: 29%-80%). All patients were staged by fluorodeoxyglucose-positron emission tomography/computed tomography staging, and 47.5% underwent mediastinal staging by endobronchial ultrasonography. Median tumor size was 5.6 cm (range: 5.1-10 cm), median SBRT dose was 50 Gy (range: 30-60 Gy) in 5 fractions (range: 3-10 fractions). Eighteen-month LC, LRC, DFS, and OS rates were 91.2%, 64.4%, 34.6%, and 59.7%, respectively. Distant failure was the predominant pattern of failure (32.5%). Three patients (7.5%) experienced grade 3 or higher toxicity. Mean posttreatment FEV1 was not significantly reduced (P=.51), but a statistically significant absolute 6.5% (P=.03) reduction in DLCO was observed. Conclusions: Lung SBRT for medically inoperable node

  3. Local control rates of metastatic renal cell carcinoma to the bone using stereotactic body radiation therapy: Is RCC truly radioresistant?′

    PubMed Central

    Bourlon, Maria T.; Bedrick, Edward; Bhatia, Shilpa; Kessler, Elizabeth R.; Flaig, Thomas W.; Fisher, Christine M.; Kavanagh, Brian D; Lam, Elaine T.; Karam, Sana D.

    2015-01-01

    Purpose We report the radiographic and clinical response rate of stereotactic body radiation therapy (SBRT) compared with conventional fractionated external beam radiation therapy (CF-EBRT) for renal cell carcinoma (RCC) bone lesions treated at our institution. Methods and materials Forty-six consecutive patients were included in the study, with 95 total lesions treated (50 SBRT, 45 CF-EBRT). We included patients who had histologic confirmation of primary RCC and radiographic evidence of metastatic bone lesions. The most common SBRT regimen used was 27 Gy in 3 fractions. Results Median follow-up was 10 months (range, 1-64 months). Median time to symptom control between SBRT and CF-EBRT were 2 (range, 0-6 weeks) and 4 weeks (range, 0-7 weeks), respectively. Symptom control rates with SBRT and CF-EBRT were significantly different (P = .020) with control rates at 10, 12, and 24 months of 74.9% versus 44.1%, 74.9% versus 39.9%, and 74.9% versus 35.7%, respectively. The median time to radiographic failure and unadjusted pain progression was 7 months in both groups. When controlling for gross tumor volume, dose per fraction, smoking, and the use of systemic therapy, biologically effective dose ≥80 Gy was significant for clinical response (hazard ratio [HR], 0.204; 95% confidence interval [CI], 0.043-0.963; P = .046) and radiographic (HR, 0.075; 95% CI, 0.013-0.430; P = .004). When controlling for gross tumor volume and total dose, biologically effective dose ≥80 Gy was again predictive of clinical local control (HR, 0.140; 95% CI, 0.025-0.787; P = .026). Toxicity rates were low and equivalent in both groups, with no grade 4 or 5 toxicity reported. Conclusions SBRT is both safe and effective for treating RCC bone metastases, with rapid improvement in symptoms after treatment and more durable clinical and radiographic response rate. Future prospective trials are needed to further define efficacy and toxicity of treatment, especially in the setting of targeted agents

  4. Stereotactic ablative radiotherapy with CyberKnife for advanced thymic carcinoma: a case report

    PubMed Central

    Fan, C.Y.; Huang, W.Y.; Jen, Y.M.; Lin, M.J.; Lin, K.T.

    2015-01-01

    Thymic carcinoma is a rare but lethal mediastinal cancer. The optimal treatment for advanced thymic carcinoma is not yet established. This report is the first known of stereotactic ablative radiotherapy (sabr) with CyberKnife (Accuray, Sunnyvale, CA, U.S.A.) as definitive therapy for thymic carcinoma. The patient, a 70-year-old woman with thymic carcinoma, invasion into neighboring organs, and pleural metastases—underwent CyberKnife sabr at 40 Gy in 5 fractions for two lesions, one in the thymus and one in the right paraspinal pleura. After 61 months of observation, a partial response was observed in the irradiated fields. However, disease progression in the non-irradiated pleura was noted. The patient underwent salvage CyberKnife sabr for the four initially nonirradiated pleural lesions. Computed tomography images obtained 10 months after the salvage therapy revealed a partial response. The patient is living, with progression-free irradiated lesions and no radiation-related toxicity. CyberKnife sabr is feasible for patients who are unable to undergo either surgery or conventionally fractionated radiation therapy. PMID:26628883

  5. Bilateral orbital metastases from breast cancer: a case report of successful palliation using stereotactic radiotherapy.

    PubMed

    Kim, Jin Ho; Choi, Sang Yul; Cho, Chul Koo; Yang, Kwang Mo; Noh, Woo Chul; Kim, Mi-Sook

    2011-01-01

    Of ophthalmic involvement from metastatic breast cancer, extraocular/intraorbital metastases are extremely rare. External beam radiotherapy has been a mainstay palliation for symptomatic orbital metastases. We present a case of bilateral orbital metastases from breast cancer successfully treated with stereotactic radiotherapy (SRT). A 38-year-old woman presented with decreased vision in the right eye for 3 weeks. Eight months previously, she underwent whole-brain radiotherapy for multiple brain metastases from breast cancer. Visual acuity was hand motion, and the eyelid closed incompletely in the affected eye. Computed tomography scans showed a 3-cm extraconal mass in the right orbit. She underwent temporary tarsorrhaphy followed by SRT. A total dose of 39 Gy was delivered to the right orbital mass in three daily fractions. Four months later, her visual function was normal in both eyes and the right orbital mass disappeared. A new lesion was detected in the left orbit. She underwent SRT for the left orbital lesion using the same dose-fractionation schedule. No radiation-related toxicities were observed. She died 19 months after the first SRT. Our case suggests that SRT may be an effective and safe treatment option in patients with orbital metastases from breast cancer. PMID:21999613

  6. Dose to the intracranial arteries in stereotactic and intensity-modulated radiotherapy for skull base tumors

    SciTech Connect

    Nieder, Carsten . E-mail: cnied@hotmail.com; Grosu, Anca L.; Stark, Sybille; Wiedenmann, Nicole; Busch, Raymonde; Kneschaurek, Peter; Molls, Michael

    2006-03-15

    Purpose: To examine retrospectively the maximum dose to the large skull base/intracranial arteries in fractionated stereotactic radiotherapy (FSRT) and intensity-modulated radiotherapy (IMRT), because of the potential risk of perfusion disturbances. Methods and Materials: Overall, 56 patients with tumors adjacent to at least one major artery were analyzed. Our strategy was to perform FSRT with these criteria: 1.8 Gy per fraction, planning target volume (PTV) enclosed by the 95% isodose, maximum dose 107%. Dose limits were applied to established organs at risk, but not the vessels. If FSRT planning failed to meet any of these criteria, IMRT was planned with the same objectives. Results: In 31 patients (median PTV, 23 cm{sup 3}), the FSRT plan fulfilled all criteria. No artery received a dose {>=}105%. Twenty-five patients (median PTV, 39 cm{sup 3}) needed IMRT planning. In 11 of 25 patients (median PTV, 85 cm{sup 3}), no plan satisfying all our criteria could be calculated. Only in this group, moderately increased maximum vessel doses were observed (106-110%, n = 7, median PTV, 121 cm{sup 3}). The median PTV dose gradient was 29% (significantly different from the 14 patients with satisfactory IMRT plans). Three of the four patients in this group had paranasal sinus tumors. Conclusion: The doses to the major arteries should be calculated in IMRT planning for critical tumor locations if a dose gradient >13% within the PTV can not be avoided because the PTV is large or includes air cavities.

  7. Increasing the Therapeutic Ratio of Stereotactic Ablative Radiotherapy by Individualized Isotoxic Dose Prescription.

    PubMed

    Zindler, Jaap D; Thomas, Charles R; Hahn, Stephen M; Hoffmann, Aswin L; Troost, Esther G C; Lambin, Philippe

    2016-02-01

    To obtain a favorable tradeoff between treatment benefits and morbidity ("therapeutic ratio"), radiotherapy (RT) dose is prescribed according to the tumor volume, with the goal of controlling the disease while respecting normal tissue tolerance levels. We propose a new paradigm for tumor dose prescription in stereotactic ablative radiotherapy (SABR) based on organ-at-risk (OAR) tolerance levels called isotoxic dose prescription (IDP), which is derived from experiences and limitations of conventionally fractionated radiotherapy. With IDP, the radiation dose is prescribed based on the predefined level of normal tissue complication probability of a nearby dose-limiting OAR at a prespecified dose-volume constraint. Simultaneously, the prescribed total tumor dose (TTD) is maximized to the technically highest achievable level in order to increase the local tumor control probability (TCP). IDP is especially relevant for tumors located at eloquent locations or for large tumors in which severe toxicity has been described. IDP will result in a lower RT dose or a treatment scheduled with more fractions if the OAR tolerance level is exceeded, and potential dose escalation occurs when the OAR tolerance level allows it and when it is expected to be beneficial (if TCP < 90%). For patients with small tumors at noneloquent sites, the current SABR dose prescription already results in high rates of local control at low toxicity rates. In this review, the concept of IDP is described in the context of SABR. PMID:26476075

  8. 4D VMAT, gated VMAT, and 3D VMAT for stereotactic body radiation therapy in lung

    NASA Astrophysics Data System (ADS)

    Chin, E.; Loewen, S. K.; Nichol, A.; Otto, K.

    2013-02-01

    Four-dimensional volumetric modulated arc therapy (4D VMAT) is a treatment strategy for lung cancers that aims to exploit relative target and tissue motion to improve organ at risk (OAR) sparing. The algorithm incorporates the entire patient respiratory cycle using 4D CT data into the optimization process. Resulting treatment plans synchronize the delivery of each beam aperture to a specific phase of target motion. Stereotactic body radiation therapy treatment plans for 4D VMAT, gated VMAT, and 3D VMAT were generated on three patients with non-small cell lung cancer. Tumour motion ranged from 1.4-3.4 cm. The dose and fractionation scheme was 48 Gy in four fractions. A B-spline transformation model registered the 4D CT images. 4D dose volume histograms (4D DVH) were calculated from total dose accumulated at the maximum exhalation. For the majority of OARs, gated VMAT achieved the most radiation sparing but treatment times were 77-148% longer than 3D VMAT. 4D VMAT plan qualities were comparable to gated VMAT, but treatment times were only 11-25% longer than 3D VMAT. 4D VMAT's improvement of healthy tissue sparing can allow for further dose escalation. Future study could potentially adapt 4D VMAT to irregular patient breathing patterns.

  9. Hypofractionated stereotactic radiotherapy in medium-sized to large arteriovenous malformations.

    PubMed

    Lindvall, Peter; Grayson, David; Bergström, Per; Bergenheim, A Tommy

    2015-06-01

    We have reviewed treatment results in terms of obliteration and complications in 24 patients with medium to large sized cerebral arteriovenous malformations (AVMs) (mean volume 18.5±8.9cm(3); range: 10-42) treated with hypofractionated stereotactic radiotherapy (HSRT). AVMs are congenital lesions associated with a high morbidity and mortality. Radiosurgery is one option for treatment. However, in larger AVMs with volumes exceeding 10cm(3) obliteration rates are less favourable and radiation induced complications more frequent. For larger AVMs, volume-staged radiosurgery is one option while another option may be the use of HSRT. Patients were treated with 6-7Gy in five fractions to a total dose of 30-35Gy (mean total dose 32.9±1.6Gy [standard error of the mean]). Sixteen patients (69.6%) showed obliteration after a mean time of 35.2±14.8 months (range: 24-60). Only one patient (4.2%) experienced symptomatic radionecrosis. Our treatment with HSRT seems safe and efficient for treatment of medium to large sized AVMs. Treatment results seem to be in line with volume-staged radiosurgery and may be an alternative for AVMs not suitable for single fraction radiosurgery. PMID:25827867

  10. Multimodality stereotactic brain tissue identification: the NASA smart probe project

    NASA Technical Reports Server (NTRS)

    Andrews, R.; Mah, R.; Aghevli, A.; Freitas, K.; Galvagni, A.; Guerrero, M.; Papsin, R.; Reed, C.; Stassinopoulos, D.

    1999-01-01

    Real-time tissue identification can benefit procedures such as stereotactic brain biopsy, functional neurosurgery and brain tumor excision. Optical scattering spectroscopy has been shown to be effective at discriminating cancer from noncancerous conditions in the colon, bladder and breast. The NASA Smart Probe extends the concept of 'optical biopsy' by using neural network techniques to combine the output from 3 microsensors contained within a cannula 2. 7 mm in diameter (i.e. the diameter of a stereotactic brain biopsy needle). Experimental data from 5 rats show the clear differentiation between tissues such as brain, nerve, fat, artery and muscle that can be achieved with optical scattering spectroscopy alone. These data and previous findings with other modalities such as (1) analysis of the image from a fiberoptic neuroendoscope and (2) the output from a microstrain gauge suggest the Smart Probe multiple microsensor technique shows promise for real-time tissue identification in neurosurgical procedures. Copyright 2000 S. Karger AG, Basel.

  11. Monte Carlo dosimetry for synchrotron stereotactic radiotherapy of brain tumours

    NASA Astrophysics Data System (ADS)

    Boudou, Caroline; Balosso, Jacques; Estève, François; Elleaume, Hélène

    2005-10-01

    A radiation dose enhancement can be obtained in brain tumours after infusion of an iodinated contrast agent and irradiation with kilovoltage x-rays in tomography mode. The aim of this study was to assess dosimetric properties of the synchrotron stereotactic radiotherapy technique applied to humans (SSR) for preparing clinical trials. We designed an interface for dose computation based on a Monte Carlo code (MCNPX). A patient head was constructed from computed tomography (CT) data and a tumour volume was modelled. Dose distributions were calculated in SSR configuration for various energy beam and iodine content in the target volume. From the calculations, it appears that the iodine-filled target (10 mg ml-1) can be efficiently irradiated by a monochromatic beam of energy ranging from 50 to 85 keV. This paper demonstrates the feasibility of stereotactic radiotherapy for treating deep-seated brain tumours with monoenergetic x-rays from a synchrotron.

  12. Stereotactic radiosurgery and immunotherapy for metastatic spinal melanoma.

    PubMed

    Caruso, James P; Cohen-Inbar, Or; Bilsky, Mark H; Gerszten, Peter C; Sheehan, Jason P

    2015-03-01

    The management of metastatic spinal melanoma involves maximizing local control, preventing recurrence, and minimizing treatment-associated toxicity and spinal cord damage. Additionally, therapeutic measures should promote mechanical stability, facilitate rehabilitation, and promote quality of life. These objectives prove difficult to achieve given melanoma's elusive nature, radioresistant and chemoresistant histology, vascular character, and tendency for rapid and early metastasis. Different therapeutic modalities exist for metastatic spinal melanoma treatment, including resection (definitive, debulking, or stabilization procedures), stereotactic radiosurgery, and immunotherapeutic techniques, but no single treatment modality has proven fully effective. The authors present a conceptual overview and critique of these techniques, assessing their effectiveness, separately and combined, in the treatment of metastatic spinal melanoma. They provide an up-to-date guide for multidisciplinary treatment strategies. Protocols that incorporate specific, goal-defined surgery, immunotherapy, and stereotactic radiosurgery would be beneficial in efforts to maximize local control and minimize toxicity. PMID:25727228

  13. Prognostic Value of MR Imaging Texture Analysis in Brain Non-Small Cell Lung Cancer Oligo-Metastases Undergoing Stereotactic Irradiation

    PubMed Central

    Tini, Paolo; Biondi, Michelangelo; Sebaste, Lucio; Vanzi, Eleonora; De Otto, Gianmarco; Rubino, Giovanni; Carfagno, Tommaso; Battaglia, Giuseppe; Pastina, Pierpaolo; Cerase, Alfonso; Mazzoni, Lorenzo Nicola; Banci Buonamici, Fabrizio; Pirtoli, Luigi

    2016-01-01

    Background  Stereotactic irradiation is widely used in brain oligo-metastases treatment. The aim of this study is to evaluate the prognostic value of magnetic resonance imaging (MRI) texture analysis (TA) of brain metastases (BM) of non-small cell lung cancer (NSCLC). Materials and methods  This study included thirty-eight consecutive patients undergoing stereotactic irradiation, that is, stereotactic fractionated radiotherapy (SRT) or radiosurgery (SRS), from January 2011 to December 2014 for 1-2 brain BM from NSCLC. Whole-brain radiotherapy (WBRT) was not delivered. The diagnostic MRI DICOM (Digital Imaging and Communications in Medicine) images were collected and analyzed with a homemade ImageJ macro, and typical TA parameters (mean, standard deviation, skewness, kurtosis, entropy, and uniformity) were evaluated for: brain progression-free survival; modality of brain metastatic progression (local progression or/and new metastases); and overall survival, after SRT/SRS. Results After SRT/SRS 14 patients (36.8%) experienced recurrence in the brain, with a recurrence in the irradiated site (five patients, 13.2%), new metastases (11 patients, 28.9%), local recurrence and new metastases (two patients, 5.25%). Nineteen patients (50%) died of tumor progression or other causes. Entropy and uniformity were significantly associated with local progression, whereas kurtosis was significantly associated with both local progression and new brain metastases. Conclusions  These results appear promising, since the knowledge of factors correlated with the modality of brain progression after stereotactic irradiation of brain oligo-metastatic foci of NSCLC might help in driving the best treatment in these patients (association of SRT/SRS with WBRT? Increase of SRT/SRS dose?). Our preliminary data needs confirmation in large patient series. PMID:27226944

  14. Quality Assurance and Commissioning of an Infrared Marker-Based Patient Positioning System for Frameless Extracranial Stereotactic Radiotherapy

    PubMed Central

    Gupta, Tejpal; Phurailatpam, Reena; Ajay, Mishra; Rajeshri, Pai; Pranshu, Mohindra; Supriya, Chopra

    2007-01-01

    Rapid advancements in imaging technology have led to remarkable improvements in identification and localization of tumors, ushering the era of high-precision techniques in contemporary radiotherapy practice. However, uncertainties in patient set-up and organ motion during a course of fractionated radiotherapy can compromise precision of radiation therapy. Excellent accuracy has been achieved with invasive and non-invasive fixation systems for stereotactic radiotherapy. This report describes the commissioning procedure and Quality Assurance studies done to evaluate the accuracy of isocenter localization by an infrared marker-based positioning system (ExacTrac). The ExacTrac has two infrared cameras that emit and detect infrared rays from reflective markers and construct three-dimensional coordinates of each marker. It detects the difference of the actual isocenter position from the planned isocenter coordinates in three translational (lateral, longitudinal, vertical, or x,y,z axes) and three rotational axes (six degree of freedom). This study performed on a flat and static phantom shows excellent accuracy achieved by the ExacTrac system. The positioning accuracy of ExacTrac (± 1 mm translational displacement and ± 1° rotational errors) can be a valuable tool in implementing frameless extracranial stereotactic radiotherapy. Nevertheless, it needs to be further evaluated on patients with inherent motion and greater positional uncertainty before being adopted in clinical practice. PMID:23675057

  15. Predictor of Severe Gastroduodenal Toxicity After Stereotactic Body Radiotherapy for Abdominopelvic Malignancies

    SciTech Connect

    Bae, Sun Hyun; Kim, Mi-Sook; Cho, Chul Koo; Kang, Jin-Kyu; Lee, Sang Yeob; Lee, Kyung-Nam; Lee, Dong Han; Han, Chul Ju; Yang, Ki Young; Kim, Sang Bum

    2012-11-15

    Purpose: To identify the predictors for the development of severe gastroduodenal toxicity (GDT) in patients treated with stereotactic body radiotherapy (SBRT) using 3 fractionations for abdominopelvic malignancies. Methods and Materials: From 2001 to 2011, 202 patients with abdominopelvic malignancies were treated with curative-intent SBRT. Among these patients, we retrospectively reviewed the clinical records of 40 patients with the eligibility criteria as follows: 3 fractionations, follow-up period {>=}1 year, absence of previous radiation therapy (RT) history or combination of external-beam RT and the presence of gastroduodenum (GD) that received a dose higher than 20% of prescribed dose. The median SBRT dose was 45 Gy (range, 33-60 Gy) with 3 fractions. We analyzed the clinical and dosimetric parameters, including multiple dose-volume histogram endpoints: V{sub 20} (volume of GD that received 20 Gy), V{sub 25}, V{sub 30}, V{sub 35}, and D{sub max} (the maximum point dose). The grade of GDT was defined by the National Cancer Institute Common Toxicity Criteria version 4.0, and GDT {>=}grade 3 was defined as severe GDT. Results: The median time to the development of severe GDT was 6 months (range, 3-12 months). Severe GDT was found in 6 patients (15%). D{sub max} was the best dosimetric predictor for severe GDT. D{sub max} of 35 Gy and 38 Gy were respectively associated with a 5% and 10% probability of the development of severe GDT. A history of ulcer before SBRT was the best clinical predictor on univariate analysis (P=.0001). Conclusions: We suggest that D{sub max} is a valuable predictor of severe GDT after SBRT using 3 fractionations for abdominopelvic malignancies. A history of ulcer before SBRT should be carefully considered as a clinical predictor, especially in patients who receive a high dose to GD.

  16. Surgical resection of epidural disease improves local control following postoperative spine stereotactic body radiotherapy

    PubMed Central

    Al-Omair, Ameen; Masucci, Laura; Masson-Cote, Laurence; Campbell, Mikki; Atenafu, Eshetu G.; Parent, Amy; Letourneau, Daniel; Yu, Eugene; Rampersaud, Raja; Massicotte, Eric; Lewis, Stephen; Yee, Albert; Thibault, Isabelle; Fehlings, Michael G.; Sahgal, Arjun

    2013-01-01

    Background Spine stereotactic body radiotherapy (SBRT) is increasingly being applied to the postoperative spine metastases patient. Our aim was to identify clinical and dosimetric predictors of local control (LC) and survival. Methods Eighty patients treated between October 2008 and February 2012 with postoperative SBRT were identified from our prospective database and retrospectively reviewed. Results The median follow-up was 8.3 months. Thirty-five patients (44%) were treated with 18–26 Gy in 1 or 2 fractions, and 45 patients (56%) with 18–40 Gy in 3–5 fractions. Twenty-one local failures (26%) were observed, and the 1-year LC and overall survival (OS) rates were 84% and 64%, respectively. The most common site of failure was within the epidural space (15/21, 71%). Multivariate proportional hazards analysis identified systemic therapy post-SBRT as the only significant predictor of OS (P = .02) and treatment with 18–26 Gy/1 or 2 fractions (P = .02) and a postoperative epidural disease grade of 0 or 1 (0, no epidural disease; 1, epidural disease that compresses dura only, P = .003) as significant predictors of LC. Subset analysis for only those patients (n = 48/80) with high-grade preoperative epidural disease (cord deformed) indicated significantly greater LC rates when surgically downgraded to 0/1 vs 2 (P = .0009). Conclusions Postoperative SBRT with high total doses ranging from 18 to 26 Gy delivered in 1–2 fractions predicted superior LC, as did postoperative epidural grade. PMID:24057886

  17. Tolerance of the Spinal Cord to Stereotactic Radiosurgery: Insights From Hemangioblastomas

    SciTech Connect

    Daly, Megan E.; Choi, Clara Y.H.; Gibbs, Iris C.; Adler, John R.; Chang, Steven D.; Lieberson, Robert E.; Soltys, Scott G.

    2011-05-01

    Purpose: To evaluate spinal cord dose-volume effects, we present a retrospective review of stereotactic radiosurgery (SRS) treatments for spinal cord hemangioblastomas. Methods and Materials: From November 2001 to July 2008, 27 spinal hemangioblastomas were treated in 19 patients with SRS. Seventeen tumors received a single fraction with a median dose of 20 Gy (range, 18-30 Gy). Ten lesions were treated using 18-25 Gy in two to three sessions. Cord volumes receiving 8, 10, 12, 14, 16, 18, 20, 22, and 24 Gy and dose to 10, 100, 250, 500, 1000, and 2000 mm{sup 3} of cord were determined. Multisession treatments were converted to single-fraction biologically effective dose (SFBED). Results: Single-fraction median cord D{sub max} was 22.7 Gy (range, 17.8-30.9 Gy). Median V10 was 454 mm{sup 3} (range, 226-3543 mm{sup 3}). Median dose to 500 mm{sup 3} cord was 9.5 Gy (range, 5.3-22.5 Gy). Fractionated median SFBED{sub 3} cord D{sub max} was 14.1 Gy{sub 3} (range, 12.3-19.4 Gy{sub 3}). Potential toxicities included a Grade 2 unilateral foot drop 5 months after SRS and 2 cases of Grade 1 sensory deficits. The actuarial 3-year local tumor control estimate was 86%. Conclusions: Despite exceeding commonly cited spinal cord dose constraints, SRS for spinal hemangioblastomas is safe and effective. Consistent with animal experiments, these data support a partial-volume tolerance model for the human spinal cord. Because irradiated cord volumes were generally small, application of these data to other clinical scenarios should be made cautiously. Further prospective studies of spinal radiosurgery are needed.

  18. 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

  19. Adaptive Liver Stereotactic Body Radiation Therapy: Automated Daily Plan Reoptimization Prevents Dose Delivery Degradation Caused by Anatomy Deformations

    SciTech Connect

    Leinders, Suzanne M.; Breedveld, Sebastiaan; Méndez Romero, Alejandra; Schaart, Dennis; Seppenwoolde, Yvette; Heijmen, Ben J.M.

    2013-12-01

    Purpose: To investigate how dose distributions for liver stereotactic body radiation therapy (SBRT) can be improved by using automated, daily plan reoptimization to account for anatomy deformations, compared with setup corrections only. Methods and Materials: For 12 tumors, 3 strategies for dose delivery were simulated. In the first strategy, computed tomography scans made before each treatment fraction were used only for patient repositioning before dose delivery for correction of detected tumor setup errors. In adaptive second and third strategies, in addition to the isocenter shift, intensity modulated radiation therapy beam profiles were reoptimized or both intensity profiles and beam orientations were reoptimized, respectively. All optimizations were performed with a recently published algorithm for automated, multicriteria optimization of both beam profiles and beam angles. Results: In 6 of 12 cases, violations of organs at risk (ie, heart, stomach, kidney) constraints of 1 to 6 Gy in single fractions occurred in cases of tumor repositioning only. By using the adaptive strategies, these could be avoided (<1 Gy). For 1 case, this needed adaptation by slightly underdosing the planning target volume. For 2 cases with restricted tumor dose in the planning phase to avoid organ-at-risk constraint violations, fraction doses could be increased by 1 and 2 Gy because of more favorable anatomy. Daily reoptimization of both beam profiles and beam angles (third strategy) performed slightly better than reoptimization of profiles only, but the latter required only a few minutes of computation time, whereas full reoptimization took several hours. Conclusions: This simulation study demonstrated that replanning based on daily acquired computed tomography scans can improve liver stereotactic body radiation therapy dose delivery.

  20. Alisertib and Fractionated Stereotactic Radiosurgery in Treating Patients With Recurrent High Grade Gliomas

    ClinicalTrials.gov

    2016-04-11

    Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Oligodendroglioma; Adult Brain Stem Glioma; Adult Diffuse Astrocytoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Mixed Glioma; Adult Oligodendroglioma; Adult Pilocytic Astrocytoma; Adult Pineal Gland Astrocytoma; Adult Subependymal Giant Cell Astrocytoma; Recurrent Adult Brain Tumor

  1. Optical spectroscopy for stereotactic biopsy of brain tumors

    NASA Astrophysics Data System (ADS)

    Markwardt, Niklas; von Berg, Anna; Fiedler, Sebastian; Goetz, Marcus; Haj-Hosseini, Neda; Polzer, Christoph; Stepp, Herbert; Zelenkov, Petr; Rühm, Adrian

    2015-07-01

    Stereotactic biopsy procedure is performed to obtain a tissue sample for diagnosis purposes. Currently, a fiber-based mechano-optical device for stereotactic biopsies of brain tumors is developed. Two different fluorophores are employed to improve the safety and reliability of this procedure: The fluorescence of intravenously applied indocyanine green (ICG) facilitates the recognition of blood vessels and thus helps minimize the risk of cerebral hemorrhages. 5- aminolevulinic-acid-induced protoporphyrin IX (PpIX) fluorescence is used to localize vital tumor tissue. ICG fluorescence detection using a 2-fiber probe turned out to be an applicable method to recognize blood vessels about 1.5 mm ahead of the fiber tip during a brain tumor biopsy. Moreover, the suitability of two different PpIX excitation wavelengths regarding practical aspects was investigated: While PpIX excitation in the violet region (at 405 nm) allows for higher sensitivity, red excitation (at 633 nm) is noticeably superior with regard to blood layers obscuring the fluorescence signal. Contact measurements on brain simulating agar phantoms demonstrated that a typical blood coverage of the tumor reduces the PpIX signal to about 75% and nearly 0% for 633 nm and 405 nm excitation, respectively. As a result, 633 nm seems to be the wavelength of choice for PpIX-assisted detection of high-grade gliomas in stereotactic biopsy.

  2. CT Imaging Findings after Stereotactic Radiotherapy for Liver Tumors

    PubMed Central

    Brook, Olga R.; Thornton, Eavan; Mendiratta-Lala, Mishal; Mahadevan, Anand; Raptopoulos, Vassilious; Brook, Alexander; Najarian, Robert; Sheiman, Robert; Siewert, Bettina

    2015-01-01

    Purpose. To study radiological response to stereotactic radiotherapy for focal liver tumors. Materials and Methods. In this IRB-approved, HIPAA-compliant study CTs of 68 consecutive patients who underwent stereotactic radiotherapy for liver tumors between 01/2006 and 01/2010 were retrospectively reviewed. Two independent reviewers evaluated lesion volume and enhancement pattern of the lesion and of juxtaposed liver parenchyma. Results. 36 subjects with hepatocellular carcinoma (HCC), 25 with liver metastases, and seven with cholangiocarcinoma (CCC) were included in study. Mean follow-up time was 5.6 ± 7.1 months for HCC, 6.4 ± 5.1 months for metastases, and 10.1 ± 4.8 months for the CCC. Complete response was seen in 4/36 (11.1%) HCCs and 1/25 (4%) metastases. Partial response (>30% decrease in long diameter) was seen in 25/36 (69%) HCCs, 14/25 (58%) metastases, and 7/7 (100%) of CCCs. Partial response followed by local recurrence (>20% increase in long diameter from nadir) occurred in 2/36 (6%) HCCs and 4/25 (17%) metastases. Liver parenchyma adjacent to the lesion demonstrated a prominent halo of delayed enhancement in 27/36 (78%) of HCCs, 19/21 (91%) of metastases, and 7/7 (100%) of CCCs. Conclusion. Sustainable radiological partial response to stereotactic radiotherapy is most frequent outcome seen in liver lesions. Prominent halo of delayed enhancement of the adjacent liver is frequent finding. PMID:26221135

  3. Stereotactic radiosurgery/stereotactic body radiation therapy-reflection on the last decade's achievements and future directions.

    PubMed

    Knisely, Jonathan; Sahgal, Arjun; Lo, Simon; Ma, Lijun; Chang, Eric

    2016-04-01

    Stereotactic radiosurgery (SRS) and its extracranial first cousin, stereotactic body radiation therapy (SBRT) have become increasingly important in the palliative treatment of cancer patients over the past decade. Appropriately designed and adequately powered clinical trials have in many clinical scenarios amply justified the time, effort, and expense associated with the development and delivery of these highly conformal and complex radiation treatment plans. Ongoing trials are anticipated to provide further confirmatory documentation of the benefits that have been readily observed by caregivers, patients, and their families. It may be predicted that future directions for palliative radiosurgery will include simplification, through greater automation, of the detailed steps that are still required for safe treatment, and thereby increase the chances for patients to receive these advanced palliative interventions at local institutions, from local caregivers. PMID:27121742

  4. Dosimetric Comparison of Intensity-Modulated Stereotactic Radiotherapy With Other Stereotactic Techniques for Locally Recurrent Nasopharyngeal Carcinoma

    SciTech Connect

    Kung, Shiris Wai Sum; Wu, Vincent Wing Cheung; Kam, Michael Koon Ming; Leung, Sing Fai; Yu, Brian Kwok Hung; Ngai, Dennis Yuen Kan; Wong, Simon Chun Fai; Chan, Anthony Tak Cheung

    2011-01-01

    Purpose: Locally recurrent nasopharyngeal carcinoma (NPC) patients can be salvaged by reirradiation with a substantial degree of radiation-related complications. Stereotactic radiotherapy (SRT) is widely used in this regard because of its rapid dose falloff and high geometric precision. The aim of this study was to examine whether the newly developed intensity-modulated stereotactic radiotherapy (IMSRT) has any dosimetric advantages over three other stereotactic techniques, including circular arc (CARC), static conformal beam (SmMLC), and dynamic conformal arc (mARC), in treating locally recurrent NPC. Methods and Materials: Computed tomography images of 32 patients with locally recurrent NPC, previously treated with SRT, were retrieved from the stereotactic planning system for contouring and computing treatment plans. Treatment planning of each patient was performed for the four treatment techniques: CARC, SmMLC, mARC, and IMSRT. The conformity index (CI) and homogeneity index (HI) of the planning target volume (PTV) and doses to the organs at risk (OARs) and normal tissue were compared. Results: All four techniques delivered adequate doses to the PTV. IMSRT, SmMLC, and mARC delivered reasonably conformal and homogenous dose to the PTV (CI <1.47, HI <0.53), but not for CARC (p < 0.05). IMSRT presented with the smallest CI (1.37) and HI (0.40). Among the four techniques, IMSRT spared the greatest number of OARs, namely brainstem, temporal lobes, optic chiasm, and optic nerve, and had the smallest normal tissue volume in the low-dose region. Conclusion: Based on the dosimetric comparison, IMSRT was optimal for locally recurrent NPC by delivering a conformal and homogenous dose to the PTV while sparing OARs.

  5. Primary Intracranial Synovial Sarcoma.

    PubMed

    Patel, Mohit; Li, Luyuan; Nguyen, Ha Son; Doan, Ninh; Sinson, Grant; Mueller, Wade

    2016-01-01

    Background. Synovial sarcoma is an aggressive soft tissue sarcoma with uncertain histological origin. The pathology frequently presents as a localized disease, especially near large joints around the knee and thigh. Intracranial disease, which is rare, has been reported as metastasis from synovial sarcoma. We report a case with no obvious primary extracranial pathology, suggesting primary intracranial disease; this has not been reported in the literature. Case Description. A 21-year-old male, with a prior right skull lesion resection for atypical spindle cell neoplasm, presented with headaches, gait instability, left arm weakness, and left homonymous hemianopsia. CT of head demonstrated a right parietal hemorrhagic lesion with mass effect, requiring surgical decompression. Histopathology revealed synovial sarcoma. FISH analysis noted the existence of the t(X;18)(p11.2;q11.2) chromosomal translocation. PET scan did not show other metastatic disease. He underwent stereotactic radiotherapy and adjuvant chemotherapy. At 2-year follow-up, he remained nonfocal without recurrence. Conclusion. We report the first known case of primary intracranial synovial sarcoma. Moreover, we stress that intracranial lesions may have a tendency for hemorrhage, requiring urgent lifesaving decompression. PMID:27247811

  6. Primary Intracranial Synovial Sarcoma

    PubMed Central

    Li, Luyuan; Sinson, Grant; Mueller, Wade

    2016-01-01

    Background. Synovial sarcoma is an aggressive soft tissue sarcoma with uncertain histological origin. The pathology frequently presents as a localized disease, especially near large joints around the knee and thigh. Intracranial disease, which is rare, has been reported as metastasis from synovial sarcoma. We report a case with no obvious primary extracranial pathology, suggesting primary intracranial disease; this has not been reported in the literature. Case Description. A 21-year-old male, with a prior right skull lesion resection for atypical spindle cell neoplasm, presented with headaches, gait instability, left arm weakness, and left homonymous hemianopsia. CT of head demonstrated a right parietal hemorrhagic lesion with mass effect, requiring surgical decompression. Histopathology revealed synovial sarcoma. FISH analysis noted the existence of the t(X;18)(p11.2;q11.2) chromosomal translocation. PET scan did not show other metastatic disease. He underwent stereotactic radiotherapy and adjuvant chemotherapy. At 2-year follow-up, he remained nonfocal without recurrence. Conclusion. We report the first known case of primary intracranial synovial sarcoma. Moreover, we stress that intracranial lesions may have a tendency for hemorrhage, requiring urgent lifesaving decompression. PMID:27247811

  7. 10 CFR 35.635 - Full calibration measurements on gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Full calibration measurements on gamma stereotactic radiosurgery units. 35.635 Section 35.635 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy Units, and Gamma Stereotactic Radiosurgery Units § 35.635 Full calibration...

  8. 10 CFR 35.645 - Periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Periodic spot-checks for gamma stereotactic radiosurgery... § 35.645 Periodic spot-checks for gamma stereotactic radiosurgery units. (a) A licensee authorized to... minimum— (1) Assure proper operation of— (i) Treatment table retraction mechanism, using backup...

  9. 10 CFR 35.2645 - Records of periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Records of periodic spot-checks for gamma stereotactic radiosurgery units. 35.2645 Section 35.2645 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2645 Records of periodic spot-checks for gamma stereotactic radiosurgery units. (a) A licensee shall retain a record of...

  10. 10 CFR 35.645 - Periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Periodic spot-checks for gamma stereotactic radiosurgery... § 35.645 Periodic spot-checks for gamma stereotactic radiosurgery units. (a) A licensee authorized to... minimum— (1) Assure proper operation of— (i) Treatment table retraction mechanism, using backup...

  11. 10 CFR 35.645 - Periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Periodic spot-checks for gamma stereotactic radiosurgery... § 35.645 Periodic spot-checks for gamma stereotactic radiosurgery units. (a) A licensee authorized to... minimum— (1) Assure proper operation of— (i) Treatment table retraction mechanism, using backup...

  12. 10 CFR 35.645 - Periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Periodic spot-checks for gamma stereotactic radiosurgery... § 35.645 Periodic spot-checks for gamma stereotactic radiosurgery units. (a) A licensee authorized to... minimum— (1) Assure proper operation of— (i) Treatment table retraction mechanism, using backup...

  13. 10 CFR 35.645 - Periodic spot-checks for gamma stereotactic radiosurgery units.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Periodic spot-checks for gamma stereotactic radiosurgery units. 35.645 Section 35.645 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy Units, and Gamma Stereotactic Radiosurgery Units § 35.645 Periodic spot-checks for...

  14. Stereotactic Radiotherapy for Cervical Spinal Intramedullary Metastasis and Multiple Brain Metastases: A Case Report

    PubMed Central

    Kawamura, Toshiki; Ohshima, Yukihiko; Takeuchi, Arisa; Mori, Toshie; Ishiguchi, Tuneo

    2016-01-01

    A case of cervical (C) spinal intramedullary metastasis and multiple small brain metastases from papillary thyroid carcinoma was presented. Spinal metastasis caused posterior neck and left shoulder pain, dysesthesia in both legs, and motor weakness in both legs and left arm, though the brain metastases were asymptomatic. Both the spinal and brain metastases were successfully treated by frameless stereotactic radiotherapy (SRT)/stereotactic radiosurgery (SRS). The patient's symptoms were almost entirely relieved within two months. A 76-year-old woman was diagnosed as having a thyroid tumor and lung metastasis by roentgenography and computed tomography. Biopsy of the thyroid tumor extending into the mediastinum revealed papillary thyroid carcinoma. She underwent surgical resection of thyroid with dissection of the mediastinum lymph node area. Internal oral radioisotope therapy was not effective for the multiple small lung metastases. She did well for 15 months, but later developed posterior neck and left shoulder pain and dysesthesia in the right leg and then dysesthesia and motor weakness in both legs. Then she experienced weakness in the left upper extremity. Magnetic resonance imaging (MRI) disclosed a small cervical spinal intramedullary mass lesion at the level of C6 and C7 on the left side as well as nine small brain lesions. The cervical spinal intramedullary metastatic tumor was treated by volumetric modulated arc radiotherapy (VMAT) SRT and the nine small brain metastatic tumors were treated by dynamic conformal arc (DCA) SRS uneventfully. A total dose of 39 Gy (100% dose) was delivered in 13 fractions for the spinal lesion (prescription, D95=95% dose; maximum dose=46.3 Gy). Single fraction SRS of 22 Gy (prescription, D95=100% dose) was performed for each of the nine small brain tumors. The spinal tumor was decreased in size on follow-up MRI two months after SRT. Three of the nine brain lesions had disappeared and six were decreased in size on

  15. Stereotactic Radiotherapy for Cervical Spinal Intramedullary Metastasis and Multiple Brain Metastases: A Case Report.

    PubMed

    Mori, Yoshimasa; Kawamura, Toshiki; Ohshima, Yukihiko; Takeuchi, Arisa; Mori, Toshie; Ishiguchi, Tuneo

    2016-01-01

    A case of cervical (C) spinal intramedullary metastasis and multiple small brain metastases from papillary thyroid carcinoma was presented. Spinal metastasis caused posterior neck and left shoulder pain, dysesthesia in both legs, and motor weakness in both legs and left arm, though the brain metastases were asymptomatic. Both the spinal and brain metastases were successfully treated by frameless stereotactic radiotherapy (SRT)/stereotactic radiosurgery (SRS). The patient's symptoms were almost entirely relieved within two months. A 76-year-old woman was diagnosed as having a thyroid tumor and lung metastasis by roentgenography and computed tomography. Biopsy of the thyroid tumor extending into the mediastinum revealed papillary thyroid carcinoma. She underwent surgical resection of thyroid with dissection of the mediastinum lymph node area. Internal oral radioisotope therapy was not effective for the multiple small lung metastases. She did well for 15 months, but later developed posterior neck and left shoulder pain and dysesthesia in the right leg and then dysesthesia and motor weakness in both legs. Then she experienced weakness in the left upper extremity. Magnetic resonance imaging (MRI) disclosed a small cervical spinal intramedullary mass lesion at the level of C6 and C7 on the left side as well as nine small brain lesions. The cervical spinal intramedullary metastatic tumor was treated by volumetric modulated arc radiotherapy (VMAT) SRT and the nine small brain metastatic tumors were treated by dynamic conformal arc (DCA) SRS uneventfully. A total dose of 39 Gy (100% dose) was delivered in 13 fractions for the spinal lesion (prescription, D95=95% dose; maximum dose=46.3 Gy). Single fraction SRS of 22 Gy (prescription, D95=100% dose) was performed for each of the nine small brain tumors. The spinal tumor was decreased in size on follow-up MRI two months after SRT. Three of the nine brain lesions had disappeared and six were decreased in size on

  16. Dosimetric verification of stereotactic radiosurgery/stereotactic radiotherapy dose distributions using Gafchromic EBT3

    SciTech Connect

    Cusumano, Davide; Fumagalli, Maria L.; Marchetti, Marcello; Fariselli, Laura; De Martin, Elena

    2015-10-01

    Aim of this study is to examine the feasibility of using the new Gafchromic EBT3 film in a high-dose stereotactic radiosurgery and radiotherapy quality assurance procedure. Owing to the reduced dimensions of the involved lesions, the feasibility of scanning plan verification films on the scanner plate area with the best uniformity rather than using a correction mask was evaluated. For this purpose, signal values dispersion and reproducibility of film scans were investigated. Uniformity was then quantified in the selected area and was found to be within 1.5% for doses up to 8 Gy. A high-dose threshold level for analyses using this procedure was established evaluating the sensitivity of the irradiated films. Sensitivity was found to be of the order of centiGray for doses up to 6.2 Gy and decreasing for higher doses. The obtained results were used to implement a procedure comparing dose distributions delivered with a CyberKnife system to planned ones. The procedure was validated through single beam irradiation on a Gafchromic film. The agreement between dose distributions was then evaluated for 13 patients (brain lesions, 5 Gy/die prescription isodose ~80%) using gamma analysis. Results obtained using Gamma test criteria of 5%/1 mm show a pass rate of 94.3%. Gamma frequency parameters calculation for EBT3 films showed to strongly depend on subtraction of unexposed film pixel values from irradiated ones. In the framework of the described dosimetric procedure, EBT3 films proved to be effective in the verification of high doses delivered to lesions with complex shapes and adjacent to organs at risk.

  17. Hypofractionated radiotherapy in pancreatic cancer: Lessons from the past in the era of stereotactic body radiation therapy.

    PubMed

    De Bari, Berardino; Porta, Laetitia; Mazzola, Rosario; Alongi, Filippo; Wagner, Anna Dorothea; Schäfer, Markus; Bourhis, Jean; Ozsahin, Mahmut

    2016-07-01

    The role of neoadjuvant and definitive radiotherapy combined or not to chemotherapy in the therapeutic approach to pancreatic cancer has not been yet elucidated. There is some evidence in favour of neoadjuvant local and/or systemic approaches that enable surgical resection in patients initially considered to be "borderline resectable". Nevertheless, most of these studies have been conducted using schedules of radiotherapy (treatment volumes, total doses, dose/fraction) that are nowadays considered not efficient enough and/or too toxic. Recently, stereotactic body radiation therapy (SBRT) has been proposed as a new therapeutic option for pancreatic cancer, both in the neoadjuvant and in the definitive setting. The aim of this study is to review the radiobiological and clinical evidences supporting hypofractionation in pancreatic cancer. Moreover, we performed an extensive review of available clinical and dosimetric data on SBRT in pancreatic cancer. PMID:27233119

  18. 4π Noncoplanar Stereotactic Body Radiation Therapy for Head-and-Neck Cancer: Potential to Improve Tumor Control and Late Toxicity

    SciTech Connect

    Rwigema, Jean-Claude M.; Nguyen, Dan; Heron, Dwight E.; Chen, Allen M.; Lee, Percy; Wang, Pin-Chieh; Vargo, John A.; Low, Daniel A.; Huq, M. Saiful; Tenn, Stephen; Steinberg, Michael L.; Kupelian, Patrick; Sheng, Ke

    2015-02-01

    Purpose: To evaluate the potential benefit of 4π radiation therapy in recurrent, locally advanced, or metastatic head-and-neck cancer treated with stereotactic body radiation therapy (SBRT). Methods and Materials: Twenty-seven patients with 29 tumors who were treated using SBRT were included. In recurrent disease (n=26), SBRT was delivered with a median 44 Gy (range, 35-44 Gy) in 5 fractions. Three patients with sinonasal mucosal melanoma, metastatic breast cancer, and primary undifferentiated carcinoma received 35 Gy, 22.5 Gy, and 40 Gy in 5 fractions, respectively. Novel 4π treatment plans were created for each patient to meet the objective that 95% of the planning target volume was covered by 100% of the prescription dose. Doses to organs at risk (OARs) and 50% dose spillage volumes were compared against the delivered clinical SBRT plans. Local control (LC), late toxicity, tumor control probability (TCP), and normal tissue complication probability were determined. Results: Using 4π plans, mean/maximum doses to all OARs were reduced by 22% to 89%/10% to 86%. With 4π plans, the 50% dose spillage volume was decreased by 33%. Planning target volume prescription dose escalation by 10 Gy and 20 Gy were achieved while keeping doses to OARs significantly improved or unchanged from clinical plans, except for the carotid artery maximum dose at 20-Gy escalation. At a median follow-up of 10 months (range, 1-41 months), crude LC was 52%. The 2-year LC of 39.2% approximated the predicted mean TCP of 42.2%, which increased to 45.9% with 4π plans. For 10-Gy and 20-Gy dose escalation, 4π plans increased TCP from 80.1% and 88.1% to 85.5% and 91.4%, respectively. The 7.4% rate of grade ≥3 late toxicity was comparable to the predicted 5.6% mean normal tissue complication probability for OARs, which was significantly reduced by 4π planning at the prescribed and escalated doses. Conclusions: 4π plans may allow dose escalation with significant and consistent

  19. A Pilot Trial of Serial 18F-Fluorodeoxyglucose Positron Emission Tomography in Patients With Medically Inoperable Stage I Non-Small-Cell Lung Cancer Treated With Hypofractionated Stereotactic Body Radiotherapy

    SciTech Connect

    Henderson, Mark A.; Hoopes, David J.; Fletcher, James W.; Lin, P.-F.; Tann, Mark; Yiannoutsos, Constantin T.; Williams, Mark D.; Fakiris, Achilles J.; McGarry, Ronald C.; Timmerman, Robert D.

    2010-03-01

    Purpose: Routine assessment was made of tumor metabolic activity as measured by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in Stage I non-small-cell lung cancer (NSCLC). This report describes PET correlates prospectively collected after stereotactic body radiotherapy (SBRT) for patients with medically inoperable NSCLC. Methods and Materials: 14 consecutive patients with medically inoperable Stage I NSCLC were enrolled. All patients received SBRT to 60-66 Gy in three fractions. Patients underwent serial planned FDG-PET/computed tomography fusion imaging before SBRT and at 2, 26, and 52 weeks after SBRT. Results: With median follow-up of 30.2 months, no patients experienced local failure. One patient developed regional failure, 1 developed distant failure, and 1 developed a second primary. The median tumor maximum standardized uptake value (SUV{sub max}) before SBRT was 8.70. The median SUV{sub max} values at 2, 26, and 52 weeks after SBRT were 6.04, 2.80, and 3.58, respectively. Patients with low pre-SBRT SUV were more likely to experience initial 2-week rises in SUV, whereas patients with high pre-SBRT SUV commonly had SUV declines 2 weeks after treatment (p = 0.036). Six of 13 patients had primary tumor SUV{sub max} >3.5 at 12 months after SBRT but remained without evidence of local disease failure on further follow-up. Conclusions: A substantial proportion of patients may have moderately elevated FDG-PET SUV{sub max} at 12 months without evidence of local failure on further follow-up. Thus, slightly elevated PET SUV{sub max} should not be considered a surrogate for local treatment failure. Our data do not support routine serial FDG-PET/computed tomography for follow-up of patients receiving SBRT for Stage I NSCLC.

  20. Salvage Stereotactic Body Radiotherapy (SBRT) Following In-Field Failure of Initial SBRT for Spinal Metastases

    SciTech Connect

    Thibault, Isabelle; Campbell, Mikki; Tseng, Chia-Lin; Atenafu, Eshetu G.; Letourneau, Daniel; Yu, Eugene; Cho, B.C. John; Lee, Young K.; Fehlings, Michael G.; Sahgal, Arjun

    2015-10-01

    Purpose: We report our experience in salvaging spinal metastases initially irradiated with stereotactic body radiation therapy (SBRT), who subsequently progressed with imaging-confirmed local tumor progression, and were re-irradiated with a salvage second SBRT course to the same level. Methods and Materials: From a prospective database, 56 metastatic spinal segments in 40 patients were identified as having been irradiated with a salvage second SBRT course to the same level. In addition, 24 of 56 (42.9%) segments had initially been irradiated with conventional external beam radiation therapy before the first course of SBRT. Local control (LC) was defined as no progression on magnetic resonance imaging at the treated segment, and calculated according to the competing risk model. Overall survival (OS) was evaluated for each patient treated by use of the Kaplan-Meier method. Results: The median salvage second SBRT total dose and number of fractions was 30 Gy in 4 fractions (range, 20-35 Gy in 2-5 fractions), and for the first course of SBRT was 24 Gy in 2 fractions (range, 20-35 Gy in 1-5 fractions). The median follow-up time after salvage second SBRT was 6.8 months (range, 0.9-39 months), the median OS was 10.0 months, and the 1-year OS rate was 48%. A longer time interval between the first and second SBRT courses predicted for better OS (P=.02). The crude LC was 77% (43/56), the 1-year LC rate was 81%, and the median time to local failure was 3.0 months (range, 2.7-16.7 months). Of the 13 local failures, 85% (11/13) and 46% (6/13) showed progression within the epidural space and paraspinal soft tissues, respectively. Absence of baseline paraspinal disease predicted for better LC (P<.01). No radiation-induced vertebral compression fractures or cases of myelopathy were observed. Conclusion: A second course of spine SBRT, most often with 30 Gy in 4 fractions, for spinal metastases that failed initial SBRT is a feasible and efficacious salvage treatment option.

  1. Treatment of brain metastases of renal cell cancer with combined hypofractionated stereotactic radiotherapy and whole brain radiotherapy with hippocampal sparing

    PubMed Central

    VRÁNA, DAVID; ŠTUDENTOVÁ, HANA; MATZENAUER, MARCEL; VLACHOVÁ, ZUZANA; CWIERTKA, KAREL; GREMLICA, DAVID; KALITA, ONDŘEJ

    2016-01-01

    Renal cell cancer patients with brain metastatic disease generally have poor prognosis. Treatment options include surgery, radiotherapy, targeted therapy or best supportive care with respect to disease burden, patient preference and performance status. In the present case report the radiotherapy technique combining whole brain radiotherapy with hippocampal sparing (hippocampal avoidance whole brain radiotherapy HA-WBRT) and hypofractionated stereotactic radiotherapy (SRT) of the brain metastases is performed in a patient with metastatic renal cell carcinoma. HA-WBRT was administered to 30 Gy in 10 fractions with sparing of the hippocampal structures and SRT of 21 Gy in 3 fractions to brain metastases which has preceded the HA-WBRT. Two single arc volumetric modulated arc radiotherapy (VMAT) plans were prepared using Monaco planning software. The HA-WBRT treatment plan achieved the following results: D2=33.91 Gy, D98=25.20 Gy, D100=14.18 Gy, D50=31.26 Gy. The homogeneity index was calculated as a deduction of the minimum dose in 2% and 98% of the planning target volume (PTV), divided by the minimum dose in 50% of the PTV. The maximum dose to the hippocampus was 17.50 Gy and mean dose was 11.59 Gy. The following doses to organs at risk (OAR) were achieved: Right opticus Dmax, 31.96 Gy; left opticus Dmax, 30.96 Gy; chiasma D max, 32,76 Gy. The volume of PTV for stereotactic radiotherapy was 3,736 cm3, with coverage D100=20.95 Gy and with only 0.11% of the PTV being irradiated to dose below the prescribed dose. HA-WBRT with SRT represents a feasible technique for radiotherapy of brain metastatic disease, however this technique is considerably demanding on departmental equipment and staff time/experience. PMID:27313693

  2. Cone-Beam Computed Tomography for On-Line Image Guidance of Lung Stereotactic Radiotherapy: Localization, Verification, and Intrafraction Tumor Position

    SciTech Connect

    Purdie, Thomas G. . E-mail: Tom.Purdie@rmp.uhn.on.ca; Bissonnette, Jean-Pierre; Franks, Kevin; Bezjak, Andrea; Payne, David; Sie, Fanny; Sharpe, Michael B.; Jaffray, David A.

    2007-05-01

    Purpose: Cone-beam computed tomography (CBCT) in-room imaging allows accurate inter- and intrafraction target localization in stereotactic body radiotherapy of lung tumors. Methods and Materials: Image-guided stereotactic body radiotherapy was performed in 28 patients (89 fractions) with medically inoperable Stage T1-T2 non-small-cell lung carcinoma. The targets from the CBCT and planning data set (helical or four-dimensional CT) were matched on-line to determine the couch shift required for target localization. Matching based on the bony anatomy was also performed retrospectively. Verification of target localization was done using either megavoltage portal imaging or CBCT imaging; repeat CBCT imaging was used to assess the intrafraction tumor position. Results: The mean three-dimensional tumor motion for patients with upper lesions (n = 21) and mid-lobe or lower lobe lesions (n = 7) was 4.2 and 6.7 mm, respectively. The mean difference between the target and bony anatomy matching using CBCT was 6.8 mm (SD, 4.9, maximum, 30.3); the difference exceeded 13.9 mm in 10% of the treatment fractions. The mean residual error after target localization using CBCT imaging was 1.9 mm (SD, 1.1, maximum, 4.4). The mean intrafraction tumor deviation was significantly greater (5.3 mm vs. 2.2 mm) when the interval between localization and repeat CBCT imaging (n = 8) exceeded 34 min. Conclusion: In-room volumetric imaging, such as CBCT, is essential for target localization accuracy in lung stereotactic body radiotherapy. Imaging that relies on bony anatomy as a surrogate of the target may provide erroneous results in both localization and verification.

  3. SU-E-J-240: The Impact On Clinical Dose-Distributions When Using MR-Images Registered with Stereotactic CT-Images in Gamma Knife Radiosurgery

    SciTech Connect

    Benmakhlouf, H; Kraepelien, T; Forander, P; Wangerid, T

    2014-06-01

    Purpose: Most Gamma knife treatments are based solely on MR-images. However, for fractionated treatments and to implement TPS dose calculations that require electron densities, CT image data is essential. The purpose of this work is to assess the dosimetric effects of using MR-images registered with stereotactic CT-images in Gamma knife treatments. Methods: Twelve patients treated for vestibular schwannoma with Gamma Knife Perfexion (Elekta Instruments, Sweden) were selected for this study. The prescribed doses (12 Gy to periphery) were delivered based on the conventional approach of using stereotactic MR-images only. These plans were imported into stereotactic CT-images (by registering MR-images with stereotactic CT-images using the Leksell gamma plan registration software). The dose plans, for each patient, are identical in both cases except for potential rotations and translations resulting from the registration. The impact of the registrations was assessed by an algorithm written in Matlab. The algorithm compares the dose-distributions voxel-by-voxel between the two plans, calculates the full dose coverage of the target (treated in the conventional approach) achieved by the CT-based plan, and calculates the minimum dose delivered to the target (treated in the conventional approach) achieved by the CT-based plan. Results: The mean dose difference between the plans was 0.2 Gy to 0.4 Gy (max 4.5 Gy) whereas between 89% and 97% of the target (treated in the conventional approach) received the prescribed dose, by the CT-plan. The minimum dose to the target (treated in the conventional approach) given by the CT-based plan was between 7.9 Gy and 10.7 Gy (compared to 12 Gy in the conventional treatment). Conclusion: The impact of using MR-images registered with stereotactic CT-images has successfully been compared to conventionally delivered dose plans showing significant differences between the two. Although CTimages have been implemented clinically; the effect of the

  4. SU-E-T-624: Quantitative Evaluation of 2D Versus 3D Dosimetry for Stereotactic Volumetric Modulated Arc Delivery Using COMPASS

    SciTech Connect

    Vikraman, S; Karrthick, K; Rajesh, T; Sambasivaselli, R; Senniandanvar, V; Kataria, T; Manigandan, D; Karthikeyan, N; Muthukumaran, M

    2014-06-15

    Purpose: The purpose of this study was to evaluate quantitatively 2D versus 3D dosimetry for stereotactic volumetric modulated arc delivery using COMPASS with 2D array. Methods: Twenty-five patients CT images and RT structures of different sites like brain, head and neck, thorax, abdomen and spine were taken from Multiplan planning system for this study. All these patients underwent radical stereotactic treatment in Cyberknife. For each patient, linac based VMAT stereotactic plans were generated in Monaco TPS v 3.1 using Elekta Beam Modulator MLC. Dose prescription was in the range of 5-20Gy/fraction.TPS calculated VMAT plan delivery accuracy was quantitatively evaluated with COMPASS measured dose and calculated dose based on DVH metrics. In order to ascertain the potential of COMPASS 3D dosimetry for stereotactic plan delivery, 2D fluence verification was performed with MatriXX using Multicube. Results: For each site, D{sub 9} {sub 5} was achieved with 100% of prescription dose with maximum 0.05SD. Conformity index (CI) was observed closer to 1.15 in all cases. Maximum deviation of 2.62 % was observed for D{sub 9} {sub 5} when compared TPS versus COMPASS measured. Considerable deviations were observed in head and neck cases compare to other sites. The maximum mean and standard deviation for D{sub 9} {sub 5}, average target dose and average gamma were -0.78±1.72, -1.10±1.373 and 0.39±0.086 respectively. Numbers of pixels passing 2D fluence verification were observed as a mean of 99.36% ±0.455 SD with 3% dose difference and 3mm DTA. For critical organs in head and neck cases, significant dose differences were observed in 3D dosimetry while the target doses were matched well within limit in both 2D and 3D dosimetry. Conclusion: The quantitative evaluations of 2D versus 3D dosimetry for stereotactic volumetric modulated plans showed the potential of highlighting the delivery errors. This study reveals that COMPASS 3D dosimetry is an effective tool for patient

  5. The treatment of recurrent brain metastases with stereotactic radiosurgery.

    PubMed

    Loeffler, J S; Kooy, H M; Wen, P Y; Fine, H A; Cheng, C W; Mannarino, E G; Tsai, J S; Alexander, E

    1990-04-01

    Between May 1986 and August 1989, we treated 18 patients with 21 recurrent or persistent brain metastases with stereotactic radiosurgery using a modified linear accelerator. To be eligible for radiosurgery, patients had to have a performance status of greater than or equal to 70% and have no evidence of (or stable) systemic disease. All but one patient had received prior radiotherapy, and were treated with stereotactic radiosurgery at the time of recurrence. Polar lesions were treated only if the patient had undergone and failed previous complete surgical resection (10 patients). Single doses of radiation (900 to 2,500 cGy) were delivered to limited volumes (less than 27 cm3) using a modified 6MV linear accelerator. The most common histology of the metastatic lesion was carcinoma of the lung (seven patients), followed by carcinoma of the breast (four patients), and melanoma (four patients). With median follow-up of 9 months (range, 1 to 39), all tumors have been controlled in the radiosurgery field. Two patients failed in the immediate margin of the treated volume and were subsequently treated with surgery and implantation of 125I to control the disease. Radiographic response was dramatic and rapid in the patients with adenocarcinoma, while slight reduction and stabilization occurred in those patients with melanoma, renal cell carcinoma, and sarcoma. The majority of patients improved neurologically following treatment, and were able to be withdrawn from corticosteroid therapy. Complications were limited and transient in nature and no cases of symptomatic radiation necrosis occurred in any patient despite previous exposure to radiotherapy. Stereotactic radiosurgery is an effective and relatively safe treatment for recurrent solitary metastases and is an appealing technique for the initial management of deep-seated lesions as a boost to whole brain radiotherapy. PMID:2179476

  6. Computation and Optimization of Dose Distributions for Rotational Stereotactic Radiosurgery

    NASA Astrophysics Data System (ADS)

    Fox, Timothy Harold

    1994-01-01

    The stereotactic radiosurgery technique presented in this work is the patient rotator method which rotates the patient in a sitting position with a stereotactic head frame attached to the skull while collimated non-coplanar radiation beams from a 6 MV medical linear accelerator are delivered to the target point. The hypothesis of this dissertation is that accurate, three-dimensional dose distributions can be computed and optimized for the patient rotator method used in stereotactic radiosurgery. This dissertation presents research results in three areas related to computing and optimizing dose distributions for the patient rotator method. A three-dimensional dose model was developed to calculate the dose at any point in the cerebral cortex using a circular and adjustable collimator system and the geometry of the radiation beam with respect to the target point. The computed dose distributions compared to experimental measurements had an average maximum deviation of <0.7 mm for the relative isodose distributions greater than 50%. A system was developed to qualitatively and quantitatively visualize the computed dose distributions with patient anatomy. A registration method was presented for transforming each dataset to a common reference system. A method for computing the intersections of anatomical contour's boundaries was developed to calculate dose-volume information. The system efficiently and accurately reduced the large computed, volumetric sets of dose data, medical images, and anatomical contours to manageable images and graphs. A computer-aided optimization method was developed for rigorously selecting beam angles and weights for minimizing the dose to normal tissue. Linear programming was applied as the optimization method. The computed optimal beam angles and weights for a defined objective function and dose constraints exhibited a superior dose distribution compared to a standard plan. The developed dose model, qualitative and quantitative visualization

  7. Histopathologic tumor response after induction chemotherapy and stereotactic body radiation therapy for borderline resectable pancreatic cancer

    PubMed Central

    Chuong, Michael D.; Frakes, Jessica M.; Figura, Nicholas; Hoffe, Sarah E.; Shridhar, Ravi; Mellon, Eric A.; Hodul, Pamela J.; Malafa, Mokenge P.; Springett, Gregory M.

    2016-01-01

    Background While clinical outcomes following induction chemotherapy and stereotactic body radiation therapy (SBRT) have been reported for borderline resectable pancreatic cancer (BRPC) patients, pathologic response has not previously been described. Methods This single-institution retrospective review evaluated BRPC patients who completed induction gemcitabine-based chemotherapy followed by SBRT and surgical resection. Each surgical specimen was assigned two tumor regression grades (TRG), one using the College of American Pathologists (CAP) criteria and one using the MD Anderson Cancer Center (MDACC) criteria. Overall survival (OS) and progression free survival (PFS) were correlated to TRG score. Results We evaluated 36 patients with a median follow-up of 13.8 months (range, 6.1-24.8 months). The most common induction chemotherapy regimen (82%) was GTX (gemcitabine, docetaxel, capecitabine). A median SBRT dose of 35 Gy (range, 30-40 Gy) in 5 fractions was delivered to the region of vascular involvement. The margin-negative resection rate was 97.2%. Improved response according to MDACC grade trended towards superior PFS (P=061), but not OS. Any neoadjuvant treatment effect according to MDACC scoring (IIa-IV vs. I) was associated with improved OS and PFS (both P=0.019). We found no relationship between CAP score and OS or PFS. Conclusions These data suggest that the increased pathologic response after induction chemotherapy and SBRT is correlated with improved survival for BRPC patients. PMID:27034789

  8. Reliability of the Bony Anatomy in Image-Guided Stereotactic Radiotherapy of Brain Metastases

    SciTech Connect

    Guckenberger, Matthias Baier, Kurt; Guenther, Iris; Richter, Anne; Wilbert, Juergen; Sauer, Otto; Vordermark, Dirk; Flentje, Michael

    2007-09-01

    Purpose: To evaluate whether the position of brain metastases remains stable between planning and treatment in cranial stereotactic radiotherapy (SRT). Methods and Materials: Eighteen patients with 20 brain metastases were treated with single-fraction (17 lesions) or hypofractionated (3 lesions) image-guided SRT. Median time interval between planning and treatment was 8 days. Before treatment a cone-beam CT (CBCT) and a conventional CT after application of i.v. contrast were acquired. Setup errors using automatic bone registration (CBCT) and manual soft-tissue registration of the brain metastases (conventional CT) were compared. Results: Tumor size was not significantly different between planning and treatment. The three-dimensional setup error (mean {+-} SD) was 4.0 {+-} 2.1 mm and 3.5 {+-} 2.2 mm according to the bony anatomy and the lesion itself, respectively. A highly significant correlation between automatic bone match and soft-tissue registration was seen in all three directions (r {>=} 0.88). The three-dimensional distance between the isocenter according to bone match and soft-tissue registration was 1.7 {+-} 0.7 mm, maximum 2.8 mm. Treatment of intracranial pressure with steroids did not influence the position of the lesion relative to the bony anatomy. Conclusion: With a time interval of approximately 1 week between planning and treatment, the bony anatomy of the skull proved to be an excellent surrogate for the target position in image-guided SRT.

  9. Severe Chest Wall Toxicity From Cryoablation in the Setting of Prior Stereotactic Ablative Radiotherapy.

    PubMed

    Chaudhuri, Aadel A; Binkley, Michael S; Aggarwal, Sonya; Qian, Yushen; Carter, Justin N; Shah, Rajesh; Loo, Billy W

    2016-01-01

    We present the case of a 42-year-old woman with metastatic synovial sarcoma of parotid origin, treated definitively with chemoradiation, who subsequently developed oligometastatic disease limited to the lungs. She underwent multiple left and right lung wedge resections and left lower lobectomy, followed by right lower lobe stereotactic ablative radiotherapy (SABR), 54 Gy in three fractions to a right lower lobe lesion abutting the chest wall. Two years later, she was treated with cryoablation for a separate right upper lobe nodule abutting the chest wall. Two months later, she presented with acute shortness of breath, pleuritic chest pain, decreased peripheral blood O2 saturation, and productive cough. A computed tomography (CT) scan demonstrated severe chest wall necrosis in the area of recent cryoablation that, in retrospect, also received a significant radiation dose from her prior SABR. This case demonstrates that clinicians should exercise caution in using cryoablation when treating lung tumors abutting a previously irradiated chest wall. Note: Drs. Loo and Shah contributed equally as co-senior authors. PMID:27004154

  10. Severe Chest Wall Toxicity From Cryoablation in the Setting of Prior Stereotactic Ablative Radiotherapy

    PubMed Central

    Chaudhuri, Aadel A; Binkley, Michael S; Aggarwal, Sonya; Qian, Yushen; Carter, Justin N; Shah, Rajesh

    2016-01-01

    We present the case of a 42-year-old woman with metastatic synovial sarcoma of parotid origin, treated definitively with chemoradiation, who subsequently developed oligometastatic disease limited to the lungs. She underwent multiple left and right lung wedge resections and left lower lobectomy, followed by right lower lobe stereotactic ablative radiotherapy (SABR), 54 Gy in three fractions to a right lower lobe lesion abutting the chest wall. Two years later, she was treated with cryoablation for a separate right upper lobe nodule abutting the chest wall. Two months later, she presented with acute shortness of breath, pleuritic chest pain, decreased peripheral blood O2 saturation, and productive cough. A computed tomography (CT) scan demonstrated severe chest wall necrosis in the area of recent cryoablation that, in retrospect, also received a significant radiation dose from her prior SABR. This case demonstrates that clinicians should exercise caution in using cryoablation when treating lung tumors abutting a previously irradiated chest wall. Note: Drs. Loo and Shah contributed equally as co-senior authors. PMID:27004154

  11. Stereotactic Body Radiation Therapy for Low- to Intermediate-risk Prostate Adenocarcinoma.

    PubMed

    Jeong, Bae-Kwon; Jeong, Hojin; Ha, In Bong; Choi, Hoon Sik; Kam, Sung Chul; Hwa, Jeong Seok; Hyun, Jae Seog; Chung, Ky Hyun; Choi, See Min; Kang, Ki Mun

    2015-06-01

    The aim of the present study was to evaluate the efficacy and toxicity of stereotactic body radiation therapy (SBRT) for low- to intermediate-risk prostate adenocarcinoma. Thirty-nine patients were retrospectively reviewed. The SBRT was delivered using the CyberKnife with the fiducial tracking method combined with In-tempo imaging. The gross target volume, which included the prostate only, was delineated on the fused CT/MRI scans. The prescription dose was delivered every other day as 5 fractions of 7.5 Gy. Venous blood was obtained before and after SBRT to assess the prostate-specific antigen (PSA) level. Toxicity was evaluated using the CTCAE, v4.03. The median follow-up time was 30.0 months. The median initial PSA level was 7.7 ng/mL. PSA levels decreased in all patients treated with SBRT, and after 5 months, the median PSA was less than 2 ng/mL. The rate of overall 3-yr actuarial biochemical failure free survival was 93.9%. Acute side effects were generally comparable with those of previous studies. The PSA change and toxicity after SBRT for low- to intermediate-risk prostate adenocarcinoma indicates favorable biochemical responses and tolerable levels of toxicity. Additionally short course treatment may produce cost benefit and convenience to patients. PMID:26028922

  12. Stereotactic Body Radiation Therapy for Low- to Intermediate-risk Prostate Adenocarcinoma

    PubMed Central

    2015-01-01

    The aim of the present study was to evaluate the efficacy and toxicity of stereotactic body radiation therapy (SBRT) for low- to intermediate-risk prostate adenocarcinoma. Thirty-nine patients were retrospectively reviewed. The SBRT was delivered using the CyberKnife with the fiducial tracking method combined with In-tempo imaging. The gross target volume, which included the prostate only, was delineated on the fused CT/MRI scans. The prescription dose was delivered every other day as 5 fractions of 7.5 Gy. Venous blood was obtained before and after SBRT to assess the prostate-specific antigen (PSA) level. Toxicity was evaluated using the CTCAE, v4.03. The median follow-up time was 30.0 months. The median initial PSA level was 7.7 ng/mL. PSA levels decreased in all patients treated with SBRT, and after 5 months, the median PSA was less than 2 ng/mL. The rate of overall 3-yr actuarial biochemical failure free survival was 93.9%. Acute side effects were generally comparable with those of previous studies. The PSA change and toxicity after SBRT for low- to intermediate-risk prostate adenocarcinoma indicates favorable biochemical responses and tolerable levels of toxicity. Additionally short course treatment may produce cost benefit and convenience to patients. PMID:26028922

  13. Stereotactic radiosurgery (SRS) in the modern management of patients with brain metastases

    PubMed Central

    Soliman, Hany; Das, Sunit; Larson, David A.; Sahgal, Arjun

    2016-01-01

    Stereotactic radiosurgery (SRS) is an established non-invasive ablative therapy for brain metastases. Early clinical trials with SRS proved that tumor control rates are superior to whole brain radiotherapy (WBRT) alone. As a result, WBRT plus SRS was widely adopted for patients with a limited number of brain metastases (“limited number” customarily means 1-4). Subsequent trials focused on answering whether WBRT upfront was necessary at all. Based on current randomized controlled trials (RCTs) and meta-analyses comparing SRS alone to SRS plus WBRT, adjuvant WBRT results in better intracranial control; however, at the expense of neurocognitive functioning and quality of life. These adverse effects of WBRT may also negatively impact on survival in younger patients. Based on the results of these studies, treatment has shifted to SRS alone in patients with a limited number of metastases. Additionally, RCTs are evaluating the role of SRS alone in patients with >4 brain metastases. New developments in SRS include fractionated SRS for large tumors and the integration of SRS with targeted systemic therapies that cross the blood brain barrier and/or stimulate an immune response. We present in this review the current high level evidence and rationale supporting SRS as the standard of care for patients with limited brain metastases, and emerging applications of SRS. PMID:26848525

  14. Effect of bite tray impression technique on relocation accuracy in frameless stereotactic radiotherapy

    SciTech Connect

    Herbert, Clare E.; Ebert, Martin A.; Barclay, D.; Whittall, David S.; Joseph, David J.; Harper, Chris S.; Spry, Nigel A

    2003-03-31

    A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate.

  15. Monte Carlo calculation of dose distributions in oligometastatic patients planned for spine stereotactic ablative radiotherapy

    NASA Astrophysics Data System (ADS)

    Moiseenko, V.; Liu, M.; Loewen, S.; Kosztyla, R.; Vollans, E.; Lucido, J.; Fong, M.; Vellani, R.; Popescu, I. A.

    2013-10-01

    Dosimetric consequences of plans optimized using the analytical anisotropic algorithm (AAA) implemented in the Varian Eclipse treatment planning system for spine stereotactic body radiotherapy were evaluated by re-calculating with BEAMnrc/DOSXYZnrc Monte Carlo. Six patients with spinal vertebral metastases were planned using volumetric modulated arc therapy. The planning goal was to cover at least 80% of the planning target volume with a prescribed dose of 35 Gy in five fractions. Tissue heterogeneity-corrected AAA dose distributions for the planning target volume and spinal canal planning organ-at-risk volume were compared against those obtained from Monte Carlo. The results showed that the AAA overestimated planning target volume coverage with the prescribed dose by up to 13.5% (mean 8.3% +/- 3.2%) when compared to Monte Carlo simulations. Maximum dose to spinal canal planning organ-at-risk volume calculated with Monte Carlo was consistently smaller than calculated with the treatment planning system and remained under spinal cord dose tolerance. Differences in dose distribution appear to be related to the dosimetric effects of accounting for body composition in Monte Carlo simulations. In contrast, the treatment planning system assumes that all tissues are water-equivalent in their composition and only differ in their electron density.

  16. Stereotactic radiosurgery for brain metastasis in non-small cell lung cancer

    PubMed Central

    Won, Yong Kyun; Lee, Ja Young; Kang, Young Nam; Jang, Ji Sun; Kang, Jin-Hyoung; Jung, So-Lyoung; Sung, Soo Yoon; Jo, In Young; Park, Hee Hyun; Lee, Dong-Soo; Chang, Ji Hyun; Lee, Yun Hee

    2015-01-01

    Purpose Stereotactic radiosurgery (SRS) has been introduced for small-sized single and oligo-metastases in the brain. The aim of this study is to assess treatment outcome, efficacy, and prognostic variables associated with survival and intracranial recurrence. Materials and Methods This study retrospectively reviewed 123 targets in 64 patients with non-small cell lung cancer (NSCLC) treated with SRS between January 2006 and December 2012. Treatment responses were evaluated using magnetic resonance imaging. Overall survival (OS) and intracranial progression-free survival (IPFS) were determined. Results The median follow-up was 13.9 months. The median OS and IPFS were 14.1 and 8.9 months, respectively. Fifty-seven patients died during the follow-up period. The 5-year local control rate was achieved in 85% of 108 evaluated targets. The 1- and 2-year OS rates were 55% and 28%, respectively. On univariate analysis, primary disease control (p < 0.001), the Eastern Cooperative Oncology Group (ECOG) performance status (0-1 vs. 2; p = 0.002), recursive partitioning analysis class (1 vs. 2; p = 0.001), and age (<65 vs. ≥65 years; p = 0.036) were significant predictive factors for OS. Primary disease control (p = 0.041) and ECOG status (p = 0.017) were the significant prognostic factors for IPFS. Four patients experienced radiation necrosis. Conclusion SRS is a safe and effective local treatment for brain metastases in patients with NSCLC. Uncontrolled primary lung disease and ECOG status were significant predictors of OS and intracranial failure. SRS might be a tailored treatment option along with careful follow-up of the intracranial and primary lung disease status. PMID:26484304

  17. Technique for Robotic Stereotactic Irradiation of Choroidal Melanoma

    PubMed Central

    Béliveau-Nadeau, Dominic; Callejo, Sonia

    2016-01-01

    Radiotherapy has a long history in the organ-sparing management of choroidal melanoma. Joining plaque radiotherapy and proton irradiation, stereotactic robotic photon irradiation is a new tool in the radiation oncologist’s armamentarium for ocular tumors. The non-coplanar fields with steep dose gradients are well suited to spare uninvolved retina, anterior chamber, and the optic nerve. In our practice, it is the preferred treatment for melanomas that are non-amenable to standard plaque brachytherapy. Since late 2010, we have treated more than 40 patients with our robotic linear accelerator. This case-based technical note outlines the technique used at the University of Montreal, Montreal, Canada. PMID:27226942

  18. Novalis Stereotactic Radiosurgery for Spinal Dural Arteriovenous Fistula

    PubMed Central

    Sung, Kyoung-Su; Song, Young-Jin

    2016-01-01

    The spinal dural arteriovenous fistula (SDAVF) is rare, presenting with progressive, insidious symptoms, and inducing spinal cord ischemia and myelopathy, resulting in severe neurological deficits. If physicians have accurate and enough information about vascular anatomy and hemodynamics, they achieve the good results though the surgery or endovascular embolization. However, when selective spinal angiography is unsuccessful due to neurological deficits, surgery and endovascular embolization might be failed because of inadequate information. We describe a patient with a history of vasospasm during spinal angiography, who was successfully treated by spinal stereotactic radiosurgery using Novalis system. PMID:27446527

  19. A Canadian Effort to Address Fractions Teaching and Learning Challenges

    ERIC Educational Resources Information Center

    Yearley, Shelley; Bruce, Catherine D.

    2014-01-01

    Teaching and learning fraction concepts provides challenges in primary schools all over the world. In this article, Shelley Yearley and Catherine Bruce describe a fractions-based research project conducted in Ontario, Canada.

  20. Lung Volume Reduction After Stereotactic Ablative Radiation Therapy of Lung Tumors: Potential Application to Emphysema

    SciTech Connect

    Binkley, Michael S.; Shrager, Joseph B.; Leung, Ann N.; Popat, Rita; Trakul, Nicholas; Atwood, Todd F.; Chaudhuri, Aadel; Maxim, Peter G.; Diehn, Maximilian; Loo, Billy W.

    2014-09-01

    Purpose: Lung volume reduction surgery (LVRS) improves dyspnea and other outcomes in selected patients with severe emphysema, but many have excessive surgical risk for LVRS. We analyzed the dose-volume relationship for lobar volume reduction after stereotactic ablative radiation therapy (SABR) of lung tumors, hypothesizing that SABR could achieve therapeutic volume reduction if applied in emphysema. Methods and Materials: We retrospectively identified patients treated from 2007 to 2011 who had SABR for 1 lung tumor, pre-SABR pulmonary function testing, and ≥6 months computed tomographic (CT) imaging follow-up. We contoured the treated lobe and untreated adjacent lobe(s) on CT before and after SABR and calculated their volume changes relative to the contoured total (bilateral) lung volume (TLV). We correlated lobar volume reduction with the volume receiving high biologically effective doses (BED, α/β = 3). Results: 27 patients met the inclusion criteria, with a median CT follow-up time of 14 months. There was no grade ≥3 toxicity. The median volume reduction of the treated lobe was 4.4% of TLV (range, −0.4%-10.8%); the median expansion of the untreated adjacent lobe was 2.6% of TLV (range, −3.9%-11.6%). The volume reduction of the treated lobe was positively correlated with the volume receiving BED ≥60 Gy (r{sup 2}=0.45, P=.0001). This persisted in subgroups determined by high versus low pre-SABR forced expiratory volume in 1 second, treated lobe CT emphysema score, number of fractions, follow-up CT time, central versus peripheral location, and upper versus lower lobe location, with no significant differences in effect size between subgroups. Volume expansion of the untreated adjacent lobe(s) was positively correlated with volume reduction of the treated lobe (r{sup 2}=0.47, P<.0001). Conclusions: We identified a dose-volume response for treated lobe volume reduction and adjacent lobe compensatory expansion after lung tumor SABR, consistent across

  1. Single- versus Multifraction Stereotactic Body Radiation Therapy for Pancreatic Adenocarcinoma: Outcomes and Toxicity

    SciTech Connect

    Pollom, Erqi L.; Alagappan, Muthuraman; Eyben, Rie von; Kunz, Pamela L.; Fisher, George A.; Ford, James A.; Poultsides, George A.; Visser, Brendan C.; Norton, Jeffrey A.; Kamaya, Aya; Cox, Veronica L.; Columbo, Laurie A.; Koong, Albert C.; Chang, Daniel T.

    2014-11-15

    Purpose: We report updated outcomes of single- versus multifraction stereotactic body radiation therapy (SBRT) for unresectable pancreatic adenocarcinoma. Methods and Materials: We included 167 patients with unresectable pancreatic adenocarcinoma treated at our institution from 2002 to 2013, with 1-fraction (45.5% of patient) or 5-fraction (54.5% of patients) SBRT. The majority of patients (87.5%) received chemotherapy. Results: Median follow-up was 7.9 months (range: 0.1-63.6). The 6- and 12-month cumulative incidence rates (CIR) of local recurrence for patients treated with single-fraction SBRT were 5.3% (95% confidence interval [CI], 0.2%-10.4%) and 9.5% (95% CI, 2.7%-16.2%), respectively. The 6- and 12-month CIR with multifraction SBRT were 3.4% (95% CI, 0.0-7.2%) and 11.7% (95% CI, 4.8%-18.6%), respectively. Median survival from diagnosis for all patients was 13.6 months (95% CI, 12.2-15.0 months). The 6- and 12- month survival rates from SBRT for the single-fraction group were 67.0% (95% CI, 57.2%-78.5%) and 30.8% (95% CI, 21.9%-43.6%), respectively. The 6- and 12- month survival rates for the multifraction group were 75.7% (95% CI, 67.2%-85.3%) and 34.9% (95% CI, 26.1%-46.8%), respectively. There were no differences in CIR or survival rates between the single- and multifraction groups. The 6- and 12-month cumulative incidence rates of gastrointestinal toxicity grade ≥3 were 8.1% (95% CI, 1.8%-14.4%) and 12.3% (95% CI, 4.7%-20.0%), respectively, in the single-fraction group, and both were 5.6% (95% CI, 0.8%-10.5%) in the multifraction group. There were significantly fewer instances of toxicity grade ≥2 with multifraction SBRT (P=.005). Local recurrence and toxicity grade ≥2 were independent predictors of worse survival. Conclusions: Multifraction SBRT for pancreatic cancer significantly reduces gastrointestinal toxicity without compromising local control.

  2. Interfraction variation in lung tumor position with abdominal compression during stereotactic body radiotherapy

    SciTech Connect

    Mampuya, Wambaka Ange; Nakamura, Mitsuhiro; Matsuo, Yukinori; Ueki, Nami; Iizuka, Yusuke; Monzen, Hajime; Mizowaki, Takashi; Hiraoka, Masahiro; Fujimoto, Takahiro; Yano, Shinsuke

    2013-09-15

    Purpose: To assess the effect of abdominal compression on the interfraction variation in tumor position in lung stereotactic body radiotherapy (SBRT) using cone-beam computed tomography (CBCT) in a larger series of patients with large tumor motion amplitude.Methods: Thirty patients with lung tumor motion exceeding 8 mm who underwent SBRT were included in this study. After translational and rotational initial setup error was corrected based on bone anatomy, CBCT images were acquired for each fraction. The residual interfraction variation was defined as the difference between the centroid position of the visualized target in three dimensions derived from CBCT scans and those derived from averaged intensity projection images. The authors compared the magnitude of the interfraction variation in tumor position between patients treated with [n= 16 (76 fractions)] and without [n= 14 (76 fractions)] abdominal compression.Results: The mean ± standard deviation (SD) of the motion amplitude in the longitudinal direction before abdominal compression was 19.9 ± 7.3 (range, 10–40) mm and was significantly (p < 0.01) reduced to 12.4 ± 5.8 (range, 5–30) mm with compression. The greatest variance of the interfraction variation with abdominal compression was observed in the longitudinal direction, with a mean ± SD of 0.79 ± 3.05 mm, compared to −0.60 ± 2.10 mm without abdominal compression. The absolute values of the 95th percentile of the interfraction variation for one side in each direction were 3.97/6.21 mm (posterior/anterior), 4.16/3.76 mm (caudal/cranial), and 2.90/2.32 mm (right/left) without abdominal compression, and 2.14/5.03 mm (posterior/anterior), 3.93/9.23 mm (caudal/cranial), and 2.37/5.45 mm (right/left) with abdominal compression. An absolute interfraction variation greater than 5 mm was observed in six (9.2%) fractions without and 13 (17.1%) fractions with abdominal compression.Conclusions: Abdominal compression was effective for reducing the amplitude

  3. Verification of dose volume histograms in stereotactic radiosurgery and radiotherapy using polymer gel and MRI

    NASA Astrophysics Data System (ADS)

    Šemnická, Jitka; Novotný, Josef, Jr.; Spěváček, Václav; Garčic, Jirí; Steiner, Martin; Judas, Libor

    2006-12-01

    In this work we focus on dose volume histograms (DVHs) measurement in stereotactic radiosurgery (SR) performed with the Leksell gamma knife (ELEKTA Instrument AB, Stockholm, Sweden) and stereotactic radiotherapy (SRT) performed with linear accelerator 6 MV Varian Clinac 2100 C/D (Varian Medical Systems, Palo Alto, USA) in conjunction with BrainLAB stereotactic system (BrainLAB, Germany) using modified BANG gel and magnetic resonance imaging (MRI). The aim of the experiments was to investigate a method for acquiring entire dose volume information from irradiated gel dosimeter and calculate DVHs.

  4. Value of serial stereotactic biopsies and impedance monitoring in the treatment of deep brain tumours.

    PubMed Central

    Broggi, G; Franzini, A

    1981-01-01

    Thirty-five patients with deep brain tumours have been submitted to transtumoral stereotactic impedance monitoring and serial biopsy. The direct examination of the biopsy samples confirmed the presumptive clinical and neuroradiological diagnosis in 25 patients, but in 10 patients the histological diagnosis differed from the presumptive one. In this second group the treatment was changed as a result of the histological findings. Stereotactic biopsy avoided the risks of "blind" management. The technique, the indications and the diagnostic advantages of stereotactic biopsy are reported with two illustrative cases. Images PMID:7021770

  5. Radiosurgery for Brain Metastases From Unknown Primary Cancers

    SciTech Connect

    Niranjan, Ajay; Kano, Hideyuki; Khan, Aftab; Kim, In-Young; Kondziolka, Douglas; Flickinger, John C.; Lunsford, L. Dade

    2010-08-01

    Purpose: We evaluated the role of Gamma Knife stereotactic radiosurgery in the multidisciplinary management of brain metastases from an undiagnosed primary cancer. Methods and Materials: Twenty-nine patients who had solitary or multiple brain metastases without a detectable primary site underwent stereotactic radiosurgery between January 1990 and March 2007 at the University of Pittsburgh. The median patient age was 61.7 years (range, 37.9-78.7 years). The median target volume was 1.0 cc (range, 0.02-23.6 cc), and the median margin radiosurgical dose was 16 Gy (range, 20-70 Gy). Results: After radiosurgery, the local tumor control rate was 88.5%. Twenty four patients died and 5 patients were living at the time of this analysis. The overall median survival was 12 months. Actuarial survival rates from stereotactic radiosurgery at 1 and 2 years were 57.2% and 36.8%, respectively. Factors associated with poor progression-free survival included large tumor volume (3 cc or more) and brainstem tumor location. Conclusions: Radiosurgery is an effective and safe minimally invasive option for patients with brain metastases from an unknown primary site.

  6. A Technique for Stereotactic Radiosurgery Treatment Planning with Helical Tomotherapy

    PubMed Central

    Soisson, Emilie T.; Hoban, Peter W.; Kammeyer, Thomas; Kapatoes, Jeffrey M.; Westerly, David C.; Basavatia, Amar; Tomé, Wolfgang A.

    2009-01-01

    Purpose The purpose of this study was to develop an efficient and effective planning technique for stereotactic radiosurgery using helical tomotherapy. Methods and Materials Planning CTs and contours of twenty patients, previously treated in our clinic for brain metastases with Linac-based radiosurgery using circular collimators, were used to develop a robust Tomotherapy planning technique. Plan calculation times as well as delivery times were recorded for all patients to allow for an efficiency evaluation. In addition, conformation and homogeneity indices were calculated as metrics to compare plan quality to that which is achieved with conventional radiosurgery delivery systems. Results A robust and efficient planning technique was identified to produce plans of radiosurgical quality using the TomoTherapy treatment planning system. Dose calculation did not exceed a few hours and resulting delivery times were less than an hour, which allows the process to fit into a single day radiosurgery workflow. Plan conformity compared favorably with published results for Gamma Knife radiosurgery. In addition, plan homogeneity was similar to Linac-based approaches. Conclusions The TomoTherapy planning software can be used to create plans of acceptable quality for stereotactic radiosurgery in a time that is appropriate for a radiosurgery workflow that requires that planning and delivery occur within one treatment day. PMID:20138501

  7. A Technique for Stereotactic Radiosurgery Treatment Planning with Helical Tomotherapy

    SciTech Connect

    Soisson, Emilie T.; Hoban, Peter W.; Kammeyer, Thomas; Kapatoes, Jeffrey M.; Westerly, David C.; Basavatia, Amar; Tome, Wolfgang A.

    2011-04-01

    The purpose of this study was to develop an efficient and effective planning technique for stereotactic radiosurgery using helical tomotherapy. Planning CTs and contours of 20 patients, previously treated in our clinic for brain metastases with linac-based radiosurgery using circular collimators, were used to develop a robust TomoTherapy planning technique. Plan calculation times as well as delivery times were recorded for all patients to allow for an efficiency evaluation. In addition, conformation and homogeneity indices were calculated as metrics to compare plan quality with that which is achieved with conventional radiosurgery delivery systems. A robust and efficient planning technique was identified to produce plans of radiosurgical quality using the TomoTherapy treatment planning system. Dose calculation did not exceed a few hours and resulting delivery times were less than 1 hour, which allows the process to fit into a single day radiosurgery workflow. Plan conformity compared favorably with published results for gamma knife radiosurgery. In addition, plan homogeneity was similar to linac-based approaches. The TomoTherapy planning software can be used to create plans of acceptable quality for stereotactic radiosurgery in a time that is appropriate for a radiosurgery workflow that requires that planning and delivery occur within 1 treatment day.

  8. Dosimetric comparison of patient setup strategies in stereotactic body radiation therapy for lung cancer

    SciTech Connect

    Wu Jianzhou; He, Tongming T.; Betzing, Christopher; Fuss, Martin; D'Souza, Warren D.

    2013-05-15

    Purpose: In this work, the authors retrospectively compared the accumulated dose over the treatment course for stereotactic body radiation therapy (SBRT) of lung cancer for three patient setup strategies. Methods: Ten patients who underwent lung SBRT were selected for this study. At each fraction, patients were immobilized using a vacuum cushion and were CT scanned. Treatment plans were performed on the simulation CT. The planning target volume (PTV) was created by adding a 5-mm uniform margin to the internal target volume derived from the 4DCT. All plans were normalized such that 99% of the PTV received 60 Gy. The plan parameters were copied onto the daily CT images for dose recalculation under three setup scenarios: skin marker, bony structure, and soft tissue based alignments. The accumulated dose was calculated by summing the dose at each fraction along the trajectory of a voxel over the treatment course through deformable image registration of each CT with the planning CT. The accumulated doses were analyzed for the comparison of setup accuracy. Results: The tumor volume receiving 60 Gy was 91.7 {+-} 17.9%, 74.1 {+-} 39.1%, and 99.6 {+-} 1.3% for setup using skin marks, bony structures, and soft tissue, respectively. The isodose line covering 100% of the GTV was 55.5 {+-} 7.1, 42.1 {+-} 16.0, and 64.3 {+-} 7.1 Gy, respectively. The corresponding average biologically effective dose of the tumor was 237.3 {+-} 29.4, 207.4 {+-} 61.2, and 258.3 {+-} 17.7 Gy, respectively. The differences in lung biologically effective dose, mean dose, and V20 between the setup scenarios were insignificant. Conclusions: The authors' results suggest that skin marks and bony structure are insufficient for aligning patients in lung SBRT. Soft tissue based alignment is needed to match the prescribed dose delivered to the tumors.

  9. Hypofractionated Stereotactic Radiation Therapy in Recurrent High-Grade Glioma: A New Challenge

    PubMed Central

    Navarria, Pierina; Ascolese, Anna Maria; Tomatis, Stefano; Reggiori, Giacomo; Clerici, Elena; Villa, Elisa; Maggi, Giulia; Bello, Lorenzo; Pessina, Federico; Cozzi, Luca; Scorsetti, Marta

    2016-01-01

    Purpose The aim of this study was to evaluate outcomes of hypofractionated stereotactic radiation therapy (HSRT) in patients re-treated for recurrent high-grade glioma. Materials and Methods From January 2006 to September 2013, 25 patients were treated. Six patients underwent radiation therapy alone, while 19 underwent combined treatment with surgery and/or chemotherapy. Only patients with Karnofsky Performance Status (KPS) > 70 and time from previous radiotherapy greater than 6 months were re-irradiated. The mean recurrent tumor volume was 35 cm3 (range, 2.46 to 116.7 cm3), and most of the patients (84%) were treated with a total dose of 25 Gy in five fractions (range, 20 to 50 Gy in 5-10 fractions). Results The median follow-up was 18 months (range, 4 to 36 months). The progression-free survival (PFS) at 1 and 2 years was 72% and 34% and the overall survival (OS) 76% and 50%, respectively. No severe toxicity was recorded. In univariate and multivariate analysis extent of resection at diagnosis significantly influenced PFS and OS (p < 0.01). Patients with smaller recurren tumor volume treated had better local control and survival. Indeed, the 2-year PFS was 40% (≤ 50 cm3) versus 11% (p=0.1) and the 2-year OS 56% versus 33% (> 50 cm3), respectively (p=0.26). Conclusion In our experience, HSRT could be a safe and feasible therapeutic option for recurrent high grade glioma even in patients with larger tumors. We believe that a multidisciplinary evaluation is mandatory to assure the best treatment for selected patients. Local treatment should also be considered as part of an integrated approach. PMID:25761491

  10. Clinical Evaluation of an Immbolization System for Stereotactic Body Radiotherapy Using Helical Tomotherapy

    SciTech Connect

    Gutierrez, Alonso N.; Stathakis, Sotirios; Crownover, Richard; Esquivel, Carlos; Shi Chengyu; Papanikolaou, Niko

    2011-07-01

    In this study, a clinical evaluation of the Body Pro-Lok{sup TM} System combined with the TomoTherapy megavoltage computed tomography (MVCT) was performed for lung and liver stereotactic body radiotherapy (SBRT) to reduce interfractional setup uncertainty. Twenty patients treated with 3-5 fractions of SBRT were analyzed retrospectively. The Body Pro-Lok{sup TM} system was used in both CT simulation and during patient treatment setup. Patients were immobilized with a vacuum cushion placed posteriorly over the thoracic region, an abdominal compression plate, and a knee and foot sponge. Pretreatment MVCT scans of the TomoTherapy HI-ART II unit were fused with the planning kVCT before delivery of each fraction to determine the interfractional setup error. A total of 84 shifts were analyzed to assess the interfractional setup accuracy. Results showed that the mean interfractional setup errors and standard deviations were -0.9 {+-} 3.1 mm, 1.2 {+-} 5.5 mm, and 6.5 {+-} 2.6 mm for lateral (IEC-X), longitudinal (IEC-Y), and vertical (IEC-Z) variations, respectively. The maximum motion was 17.1 mm in the longitudinal direction. When all 3 translational coordinates were analyzed, a mean composite displacement vector of 8.2 {+-} 2.0 mm (range 4.1-11.7 mm) was obtained for all patients. Based on the findings, image-guided SBRT using the Body Pro-Lok{sup TM} system in conjunction with the MVCT of TomoTherapy is capable of minimizing interfractional setup error and improving treatment accuracy.

  11. Dose Escalated Liver Stereotactic Body Radiation Therapy at the Mean Respiratory Position

    SciTech Connect

    Velec, Michael; Moseley, Joanne L.; Dawson, Laura A.; Brock, Kristy K.

    2014-08-01

    Purpose: The dosimetric impact of dose probability based planning target volume (PTV) margins for liver cancer patients receiving stereotactic body radiation therapy (SBRT) was compared with standard PTV based on the internal target volume (ITV). Plan robustness was evaluated by accumulating the treatment dose to ensure delivery of the intended plan. Methods and Materials: Twenty patients planned on exhale CT for 27 to 50 Gy in 6 fractions using an ITV-based PTV and treated free-breathing were retrospectively evaluated. Isotoxic, dose escalated plans were created on midposition computed tomography (CT), representing the mean breathing position, using a dose probability PTV. The delivered doses were accumulated using biomechanical deformable registration of the daily cone beam CT based on liver targeting at the exhale or mean breathing position, for the exhale and midposition CT plans, respectively. Results: The dose probability PTVs were on average 38% smaller than the ITV-based PTV, enabling an average ± standard deviation increase in the planned dose to 95% of the PTV of 4.0 ± 2.8 Gy (9 ± 5%) on the midposition CT (P<.01). For both plans, the delivered minimum gross tumor volume (GTV) doses were greater than the planned nominal prescribed dose in all 20 patients and greater than the planned dose to 95% of the PTV in 18 (90%) patients. Nine patients (45%) had 1 or more GTVs with a delivered minimum dose more than 5 Gy higher with the midposition CT plan using dose probability PTV, compared with the delivered dose with the exhale CT plan using ITV-based PTV. Conclusions: For isotoxic liver SBRT planned and delivered at the mean respiratory, reduced dose probability PTV enables a mean escalation of 4 Gy (9%) in 6 fractions over ITV-based PTV. This may potentially improve local control without increasing the risk of tumor underdosing.

  12. Obesity Increases the Risk of Chest Wall Pain From Thoracic Stereotactic Body Radiation Therapy

    SciTech Connect

    Welsh, James; Thomas, Jimmy; Shah, Deep; Allen, Pamela K.; Wei, Xiong; Mitchell, Kevin; Gao, Song; Balter, Peter; Komaki, Ritsuko; Chang, Joe Y.

    2011-09-01

    Purpose: Stereotactic body radiation therapy (SBRT) is increasingly being used to treat thoracic tumors. We attempted here to identify dose-volume parameters that predict chest wall toxicity (pain and skin reactions) in patients receiving thoracic SBRT. Patients and Methods: We screened a database of patients treated with SBRT between August 2004 and August 2008 to find patients with pulmonary tumors within 2.5 cm of the chest wall. All patients received a total dose of 50 Gy in four daily 12.5-Gy fractions. Toxicity was scored according to the NCI-CTCAE V3.0. Results: Of 360 patients in the database, 265 (268 tumors) had tumors within <2.5 cm of the chest wall; 104 (39%) developed skin toxicity (any grade); 14 (5%) developed acute pain (any grade), and 45 (17%) developed chronic pain (Grade 1 in 22 cases [49%] and Grade 2 or 3 in 23 cases [51%]). Both skin toxicity and chest wall pain were associated with the V{sub 30}, or volume of the chest wall receiving 30 Gy. Body mass index (BMI) was also strongly associated with the development of chest pain: patients with BMI {>=}29 had almost twice the risk of chronic pain (p = 0.03). Among patients with BMI >29, diabetes mellitus was a significant contributing factor to the development of chest pain. Conclusion: Safe use of SBRT with 50 Gy in four fractions for lesions close to the chest wall requires consideration of the chest wall volume receiving 30 Gy and the patient's BMI and diabetic state.

  13. Dose escalation with stereotactic body radiation therapy boost for locally advanced non small cell lung cancer

    PubMed Central

    2013-01-01

    Introduction Low survival outcomes have been reported for the treatment of locally advanced non small cell lung cancer (LA-NSCLC) with the standard of care treatment of concurrent chemoradiation (cCRT). We present our experience of dose escalation using stereotactic body radiosurgery (SBRT) following conventional cCRT for patients with LA-NSCLC. Methods Sixteen patients with a median age of 67.5 treated with fractionated SBRT from 2010 to 2012 were retrospectively analyzed. Nine (56%) of the patients had stage IIIB, 6 (38%) has stage IIIA, and 1 (6%) had recurrent disease. Majority of the patients (63%) presented with N2 disease. All patients had a PET CT for treatment planning. Patients received conventional cCRT to a median dose of 50.40 Gy (range 45–60) followed by an SBRT boost with an average dose of 25 Gy (range 20–30) given over 5 fractions. Results With a median follow-up of 14 months (range, 1–14 months), 1-year overall survival (OS), progression free survival (PFS), local control (LC), regional control (RC), and distant control (DC) rates were, 78%, 42%, 76%, 79%, and 71%, respectively. Median times to disease progression and regional failure were 10 months and 18 months, respectively. On univariate analysis, advanced age and nodal status were worse prognostic factors of PFS (p < 0.05). Four patients developed radiation pneumonitis and one developed hemoptysis. Treatment was interrupted in one patient who required hospitalization due to arrhythmias and pneumonia. Conclusion Risk adaptive dose escalation with SBRT following external beam radiotherapy is possible and generally tolerated treatment option for patients with LA-NSCLC. PMID:23842112

  14. Acceptable Toxicity After Stereotactic Body Radiation Therapy for Liver Tumors Adjacent to the Central Biliary System

    SciTech Connect

    Eriguchi, Takahisa; Takeda, Atsuya; Sanuki, Naoko; Oku, Yohei; Aoki, Yousuke; Shigematsu, Naoyuki; Kunieda, Etsuo

    2013-03-15

    Purpose: To evaluate biliary toxicity after stereotactic body radiation therapy (SBRT) for liver tumors. Methods and Materials: Among 297 consecutive patients with liver tumors treated with SBRT of 35 to 50 Gy in 5 fractions, patients who were irradiated with >20 Gy to the central biliary system (CBS), including the gallbladder, and had follow-up times >6 months were retrospectively analyzed. Toxicity profiles, such as clinical symptoms and laboratory and radiologic data especially for obstructive jaundice and biliary infection, were investigated in relation to the dose volume and length relationship for each biliary organ. Results: Fifty patients with 55 tumors were irradiated with >20 Gy to the CBS. The median follow-up period was 18.2 months (range, 6.0-80.5 months). In the dose length analysis, 39, 34, 14, and 2 patients were irradiated with >20 Gy, >30 Gy, >40 Gy, and >50 Gy, respectively, to >1 cm of the biliary tract. Seven patients were irradiated with >20 Gy to >20% of the gallbladder. Only 2 patients experienced asymptomatic bile duct stenosis. One patient, metachronously treated twice with SBRT for tumors adjacent to each other, had a transient increase in hepatic and biliary enzymes 12 months after the second treatment. The high-dose area >80 Gy corresponded to the biliary stenosis region. The other patient experienced biliary stenosis 5 months after SBRT and had no laboratory changes. The biliary tract irradiated with >20 Gy was 7 mm and did not correspond to the bile duct stenosis region. No obstructive jaundice or biliary infection was found in any patient. Conclusions: SBRT for liver tumors adjacent to the CBS was feasible with minimal biliary toxicity. Only 1 patient had exceptional radiation-induced bile duct stenosis. For liver tumors adjacent to the CBS without other effective treatment options, SBRT at a dose of 40 Gy in 5 fractions is a safe treatment with regard to biliary toxicity.

  15. Hypofractionated stereotactic radiotherapy for benign intracranial tumours of the cavernous sinus.

    PubMed

    Haghighi, Neda; Seely, Anna; Paul, Eldho; Dally, Michael

    2015-09-01

    We present our experience with hypofractionated stereotactic radiotherapy (HSRT) using 15 fractions to treat benign conditions of the cavernous sinus (CS) and emphasise the outcome in terms of cranial nerve (CN) function and toxicity for long term safety and efficacy. We performed a retrospective review of prospectively collected data on 112 patients with benign tumours of the CS treated with HSRT between 1 January 1998 and 31 December 2009. While all tumours involved the CS, a separate analysis was undertaken for meningiomas and pituitary adenomas. The median follow-up was 77 months (range: 2.3-177). Fifty-seven patients (51%) had a diagnosis of meningioma and 55 (49%) had pituitary adenomas. Prior to HSRT, 82 patients (73%) underwent microsurgery. The median tumour volume was 6.6 cm(3) for meningiomas and 3.4 cm(3) for pituitary adenomas (interquartile range: 2.8-7.9), and the mean prescribed dose was 38 Gy (range: 37.5-40.0) to the tumour margin, delivered in 15 fractions. After HSRT, 57% of all preexisting cranial neuropathies either resolved or improved and 38% remained stable, whereas 5% deteriorated. The diagnosis of meningioma was the only variable associated with recovery of cranial