WorldWideScience

Sample records for hypofractionated stereotactic radiosurgery

  1. Hypofractionated Stereotactic Radiosurgery in a Large Bilateral Thalamic and Basal Ganglia Arteriovenous Malformation

    Directory of Open Access Journals (Sweden)

    Janet Lee

    2013-01-01

    Full Text Available Purpose. Arteriovenous malformations (AVMs in the basal ganglia and thalamus have a more aggressive natural history with a higher morbidity and mortality than AVMs in other locations. Optimal treatment—complete obliteration without new neurological deficits—is often challenging. We present a patient with a large bilateral basal ganglia and thalamic AVM successfully treated with hypofractionated stereotactic radiosurgery (HFSRS with intensity modulated radiotherapy (IMRT. Methods. The patient was treated with hypofractionated stereotactic radiosurgery to 30 Gy at margin in 5 fractions of 9 static fields with a minimultileaf collimator and intensity modulated radiotherapy. Results. At 10 months following treatment, digital subtraction angiography showed complete obliteration of the AVM. Conclusions. Large bilateral thalamic and basal ganglia AVMs can be successfully treated with complete obliteration by HFSRS with IMRT with relatively limited toxicity. Appropriate caution is recommended.

  2. Comparative effectiveness research in radiation oncology: stereotactic radiosurgery, hypofractionation, and brachytherapy.

    Science.gov (United States)

    Aneja, Sanjay; Yu, James B

    2014-01-01

    Radiation oncology encompasses a diverse spectrum of treatment modalities, including stereotactic radiosurgery, hypofractionated radiotherapy, and brachytherapy. Though all these modalities generally aim to do the same thing-treat cancer with therapeutic doses of radiation while relatively sparing normal tissue from excessive toxicity, the general radiobiology and physics underlying each modality are distinct enough that their equivalence is not a given. Given the continued innovation in radiation oncology, the comparative effectiveness of these modalities is important to review. Given the broad scope of radiation oncology, this article focuses on the 3 most common sites requiring radiation treatment: breast, prostate, and lung cancer.

  3. Stereotactic radiosurgery

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    Leksell, L. (Karolinska Sjukhuset, Stockholm (Sweden))

    1983-09-01

    The development and scope of stereotactic radiosurgery is described. The technique, which combines well with the latest diagnostic methods, has already proved a safe and effective way of treating inaccessible cerebral lesions and in particular small arteriovenous malformations, acoustic neuroma and the solid component of craniopharyngioma, as well as playing an increasingly useful role in the therapy of pituitary adenoma.

  4. Adjuvant therapy after resection of brain metastases. Frameless image-guided LINAC-based radiosurgery and stereotactic hypofractionated radiotherapy

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    Broemme, J.; Aebersold, D.M.; Pica, A. [Bern Univ., Bern Univ. Hospital (Switzerland). Dept. of Radiation Oncology; Abu-Isa, J.; Beck, J.; Raabe, A. [Bern Univ., Bern Univ. Hospital (Switzerland). Neurosurgery; Kottke, R.; Wiest, R. [Bern Univ., Bern Univ. Hospital (Switzerland). Neuroradiology; Malthaner, M.; Schmidhalter, D. [Bern Univ., Bern Univ. Hospital (Switzerland). Div. of Medical Radiation Physics

    2013-09-15

    Background: Tumor bed stereotactic radiosurgery (SRS) after resection of brain metastases is a new strategy to delay or avoid whole-brain irradiation (WBRT) and its associated toxicities. This retrospective study analyzes results of frameless image-guided linear accelerator (LINAC)-based SRS and stereotactic hypofractionated radiotherapy (SHRT) as adjuvant treatment without WBRT. Materials and methods: Between March 2009 and February 2012, 44 resection cavities in 42 patients were treated with SRS (23 cavities) or SHRT (21 cavities). All treatments were delivered using a stereotactic LINAC. All cavities were expanded by {>=} 2 mm in all directions to create the clinical target volume (CTV). Results: The median planning target volume (PTV) for SRS was 11.1 cm{sup 3}. The median dose prescribed to the PTV margin for SRS was 17 Gy. Median PTV for SHRT was 22.3 cm{sup 3}. The fractionation schemes applied were: 4 fractions of 6 Gy (5 patients), 6 fractions of 4 Gy (6 patients) and 10 fractions of 4 Gy (10 patients). Median follow-up was 9.6 months. Local control (LC) rates after 6 and 12 months were 91 and 77 %, respectively. No statistically significant differences in LC rates between SRS and SHRT treatments were observed. Distant brain control (DBC) rates at 6 and 12 months were 61 and 33 %, respectively. Overall survival (OS) at 6 and 12 months was 87 and 63.5 %, respectively, with a median OS of 15.9 months. One patient treated by SRS showed symptoms of radionecrosis, which was confirmed histologically. Conclusion: Frameless image-guided LINAC-based adjuvant SRS and SHRT are effective and well tolerated local treatment strategies after resection of brain metastases in patients with oligometastatic disease. (orig.)

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

    Science.gov (United States)

    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

  6. Stereotactic Radiosurgery and Stereotactic Body Radiotherapy (SBRT)

    Science.gov (United States)

    ... is the procedure performed? • Stereotactic Radiosurgery Using the Gamma Knife Gamma Knife radiosurgery involves four phases: placement of the head ... also a guiding device that makes sure the Gamma Knife beams are focused exactly where the treatment is ...

  7. Outcome Evaluation of Oligometastatic Patients Treated with Surgical Resection Followed by Hypofractionated Stereotactic Radiosurgery (HSRS) on the Tumor Bed, for Single, Large Brain Metastases

    Science.gov (United States)

    Pessina, Federico; Navarria, Pierina; Cozzi, Luca; Ascolese, Anna Maria; Maggi, Giulia; Riva, Marco; Masci, Giovanna; D’Agostino, Giuseppe; Finocchiaro, Giovanna; Santoro, Armando; Bello, Lorenzo; Scorsetti, Marta

    2016-01-01

    Purpose The aim of this study was to evaluate the benefit of a combined treatment, surgery followed by adjuvant hypofractionated stereotactic radiosurgery (HSRS) on the tumor bed, in oligometastatic patients with single, large brain metastasis (BM). Methods and Materials Fom January 2011 to March 2015, 69 patients underwent complete surgical resection followed by HSRS with a total dose of 30Gy in 3 daily fractions. Clinical outcome was evaluated by neurological examination and MRI 2 months after radiotherapy and then every 3 months. Local progression was defined as radiographic increase of the enhancing abnormality in the irradiated volume, and brain distant progression as the presence of new brain metastases or leptomeningeal enhancement outside the irradiated volume. Surgical morbidity and radiation-therapy toxicity, local control (LC), brain distant progression (BDP), and overall survival (OS) were evaluated. Results The median preoperative volume and maximum diameter of BM was 18.5cm3 (range 4.1–64.2cm3) and 3.6cm (range 2.1-5-4cm); the median CTV was 29.0cm3 (range 4.1–203.1cm3) and median PTV was 55.2cm3 (range 17.2–282.9cm3). The median follow-up time was 24 months (range 4–33 months). The 1-and 2-year LC in site of treatment was 100%; the median, 1-and 2-year BDP was 11.9 months, 19.6% and 33.0%; the median, 1-and 2-year OS was 24 months (range 4–33 months), 91.3% and 73.0%. No severe postoperative morbidity or radiation therapy toxicity occurred in our series. Conclusions Multimodal approach, surgery followed by HSRS, can be an effective treatment option for selected patients with single, large brain metastases from different solid tumors. PMID:27348860

  8. Stereotactic radiosurgery - Gamma Knife

    Science.gov (United States)

    ... being treated. As compared to other types of radiation therapy, Gamma Knife treatment is much less likely to damage ... of radiosurgery alone vs radiosurgery with whole brain radiation ... Knife radiosurgery patient resource center. 2015. www.elekta. ...

  9. Stereotactic radiosurgery - discharge

    Science.gov (United States)

    Gamma knife - discharge; Cyberknife - discharge; Stereotactic radiotherapy - discharge; Fractionated stereotactic radiotherapy - discharge; Cyclotrons - discharge; Linear accelerator - discharge; Lineacs - ...

  10. 放射外科治疗面肌抽搐的初步研究%Treatment of idiopathic hemifacial spasm with with radiosurgery or hypofractionated stereotactic radiotherapy:preliminary results

    Institute of Scientific and Technical Information of China (English)

    吕学明; 袁绍纪; 孙希炎; 陈援朝; 吕福林; 吕晓彦; 解相礼; 许呈来

    2011-01-01

    Objective In this article we present four patients affected by idiopathic hemifa-cial spasm, refractory to medical therapy and botulinum toxin injections, who were treated by ra-diosurgery and hypofractionated stereotactic radiotherapy in four cases. Methods Radiosurgery, with a single dose of 5 Gy, was used in the first patient affected by idiopathic hemifacial spasm and autoimmune polyneuropathy with severe hypoacusia; hypofractionated stereotactic radiotherapy, with 15 Gy in 5 fractions of 3 Gy each, was preferred in the other 3 cases. In all patients, the target consisted of the vestibulocochlear-facial bundle immediately before its entry into the internal acoustic foramen. Results A marked improvement of symptoms was observed in 2 patients, and almost complete disappearance in the other cases, with no complications, particularly, auditory. Conclusion Radiosurgery or hypofractionated stereotactic radiotherapy could represent a therapeutic alternative to microvascular decompression for idiopathic hemifacial spasm for patients not suitable for surgery.%目的 探讨放射治疗对原发性面肌抽搐的效果及并发症分析.方法 其中1例听觉减弱的患者单次给予一次性剂量8 Gy治疗,其余3位听觉正常患者给予5天5次连续不同部位每次3Gy剂量,共计15Gy.所有患者靶点选择在面听神经束出脑干处至进人内听道前部分.结果 2例患者症状消失,1例症状明显减轻.另1例口服药物治疗下症状未见发作.未见明显并发症,特别是听、面神经功能无损伤.4例患者均放疗后2~4周短期随访及18个月到42个月的中期随访,放疗结果满意.结论 放疗治疗原发性面肌抽搐仍为不适于手术患者的一种治疗选择方法,疗效确切.

  11. Stereotactic radiosurgery for intracranial meningiomas

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    Kida, Yoshihisa; Kobayashi, Tatsuya; Tanaka, Takayuki; Oyama, Hirofumi; Iwakoshi, Takayasu (Komaki City Hospital, Hokkaido (Japan))

    1994-07-01

    Stereotactic radiosurgery for intracranial meningiomas was attempted using a 201-source cobalt gamma knife. Forty patients bearing 42 tumors were involved in this study. Their ages ranged from 30 to 91 years, with an average of 55.1 years. The most frequent sites of origin were the parasellar and petroclival regions. The mean tumor diameter was 27.2 mm and the marginal tumor dose of radiosurgery ranged from 10 to 20 Gy, depending on tumor location and size. Serial imaging studies with MRI were obtained in all 40 cases, in which minor tumor shrinkage was demonstrated in 7.9%, 40.0% and 53.3% at 6, 12 and 18 months after radiosurgery respectively. Only two tumors became enlarged after the treatment. Obvious low signal intensity on MRI, indicating central tumor necrosis, was found in 32% at 12 months and 40% at 18 months. Four large tumors over 40 mm in mean diameter were treated by staged radiosurgery with intervals of 1.5 to 7 months. A similar good response was able to be obtained in all 4 cases, even though they were treated with a marginal dose less than 12 Gy. Symptomatic edema occurred in 5 cases (12.5%) within 12 months and required corticosteroid therapy and hyperosmotic diuresis. In conclusion stereotactic radiosurgery has proved to be an effective and relatively safe method for the treatment of intracranial meningiomas. (author).

  12. Imaging Advances in Stereotactic Radiosurgery.

    Science.gov (United States)

    Tsien, Christina; Drzymala, Robert E; Rich, Keith

    2015-01-01

    Novel functional and metabolic MRI imaging provides the ability to analyze tumor tissue properties including tumor vasculature, vascular permeability, tumor cellularity, hypoxia, and tumor proliferation. Stereotactic radiosurgery involves the delivery of a very precise, focal dose of radiation to a target. Recent advances in MR imaging have the potential to improve accuracy for target volume delineation and to potentially improve outcome. Novel MR imaging techniques may also be used in subsequent post-treatment follow-up to distinguish between tumor recurrences versus non-neoplastic treatment-related changes. In this paper, we address multiparametric MR imaging and cerebral angiography as tools to reduce toxicity.

  13. Adaptive hypofractionated gamma knife radiosurgery for a large brainstem metastasis

    Directory of Open Access Journals (Sweden)

    Georges Sinclair

    2016-01-01

    Conclusion: GK-based stereotactic adaptive hypofractionation proved to be effective to achieve tumor control while limiting local adverse reactions. This surgical modality should be considered when managing larger brain lesions in critical areas.

  14. Adaptive hypofractionated gamma knife radiosurgery for a large brainstem metastasis

    DEFF Research Database (Denmark)

    Sinclair, Georges; Bartek, Jiri; Martin, Heather

    2016-01-01

    BACKGROUND: To demonstrate how adaptive hypofractionated radiosurgery by gamma knife (GK) can be successfully utilized to treat a large brainstem metastasis - a novel approach to a challenging clinical situation. CASE DESCRIPTION: A 42-year-old woman, diagnosed with metastatic nonsmall cell lung...... adaptive hypofractionation proved to be effective to achieve tumor control while limiting local adverse reactions. This surgical modality should be considered when managing larger brain lesions in critical areas....

  15. The radiosurgery fractionation quandary: single fraction or hypofractionation?

    Science.gov (United States)

    Kirkpatrick, John P; Soltys, Scott G; Lo, Simon S; Beal, Kathryn; Shrieve, Dennis C; Brown, Paul D

    2017-04-01

    Stereotactic radiosurgery (SRS), typically administered in a single session, is widely employed to safely, efficiently, and effectively treat small intracranial lesions. However, for large lesions or those in close proximity to critical structures, it can be difficult to obtain an acceptable balance of tumor control while avoiding damage to normal tissue when single-fraction SRS is utilized. Treating a lesion in 2 to 5 fractions of SRS (termed "hypofractionated SRS" [HF-SRS]) potentially provides the ability to treat a lesion with a total dose of radiation that provides both adequate tumor control and acceptable toxicity. Indeed, studies of HF-SRS in large brain metastases, vestibular schwannomas, meningiomas, and gliomas suggest that a superior balance of tumor control and toxicity is observed compared with single-fraction SRS. Nonetheless, a great deal of effort remains to understand radiobiologic mechanisms for HF-SRS driving the dose-volume response relationship for tumors and normal tissues and to utilize this fundamental knowledge and the results of clinic studies to optimize HF-SRS. In particular, the application of HF-SRS in the setting of immunomodulatory cancer therapies offers special challenges and opportunities.

  16. Hypofractionation regimens for stereotactic radiotherapy for large brain tumors.

    Science.gov (United States)

    Yuan, Jiankui; Wang, Jian Z; Lo, Simon; Grecula, John C; Ammirati, Mario; Montebello, Joseph F; Zhang, Hualin; Gupta, Nilendu; Yuh, William T C; Mayr, Nina A

    2008-10-01

    To investigate equivalent regimens for hypofractionated stereotactic radiotherapy (HSRT) for brain tumor treatment and to provide dose-escalation guidance to maximize the tumor control within the normal brain tolerance. The linear-quadratic model, including the effect of nonuniform dose distributions, was used to evaluate the HSRT regimens. The alpha/beta ratio was estimated using the Gammaknife stereotactic radiosurgery (GKSRS) and whole-brain radiotherapy experience for large brain tumors. The HSRT regimens were derived using two methods: (1) an equivalent tumor control approach, which matches the whole-brain radiotherapy experience for many fractions and merges it with the GKSRS data for few fractions; and (2) a normal-tissue tolerance approach, which takes advantages of the dose conformity and fractionation of HSRT to approach the maximal dose tolerance of the normal brain. A plausible alpha/beta ratio of 12 Gy for brain tumor and a volume parameter n of 0.23 for normal brain were derived from the GKSRS and whole-brain radiotherapy data. The HSRT prescription regimens for the isoeffect of tumor irradiation were calculated. The normal-brain equivalent uniform dose decreased as the number of fractions increased, because of the advantage of fractionation. The regimens for potential dose escalation of HSRT within the limits of normal-brain tolerance were derived. The designed hypofractionated regimens could be used as a preliminary guide for HSRT dose prescription for large brain tumors to mimic the GKSRS experience and for dose escalation trials. Clinical studies are necessary to further tune the model parameters and validate these regimens.

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

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    Wang Xin; Liu Xiaoxia; Mei Guanghai; Dai Jiazhong; Pan Li [Departments of Neurosurgery and CyberKnife, Huashan Hospital, Fudan University, Shanghai (China); Wang Enmin, E-mail: wangem@fudan.edu.cn [Departments of Neurosurgery and CyberKnife, Huashan Hospital, Fudan University, Shanghai (China)

    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. Stereotactic radiosurgery: a "targeted" therapy for cancer

    Institute of Scientific and Technical Information of China (English)

    Ming Zeng; Liang-Fu Han

    2012-01-01

    The developments of medicine always follow innovations in science and technology.In the past decade,such innovations have made cancer-related targeted therapies possible.In general,the term "targeted therapy" has been used in reference to cellular and molecular level oriented therapies.However,improvements in the delivery and planning of traditional radiation therapy have also provided cancer patients more options for "targeted" treatment,notably stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT).In this review,the progress and controversies of SRS and SBRT are discussed to show the role of stereotactic radiation therapy in the ever evolving multidisciplinary care of cancer patients.

  19. Stereotactic radiosurgery for multiple brain metastases

    Science.gov (United States)

    Lee, Anna; (Josh Yamada, Yoshiya

    2017-01-01

    Whole brain radiation therapy has been the traditional treatment of choice for patients with multiple brain metastases. Although stereotactic radiosurgery is widely accepted for the management to up to 4 brain metastases, its use is still controversial in cases of 5 or more brain metastases. Randomized trials have suggested that stereotactic radiosurgery alone is appropriate in up to 4 metastases without concomitant whole brain radiation. Level 1 evidence also suggests that withholding whole brain radiation may also reduce the impact of radiation on neurocognitive function and also may even offer a survival advantage. A recent analysis of a large multicentre prospective database has suggested that there are no differences in outcomes such as the likelihood of new metastasis or leptomeningeal disease in cases of 2-10 brain metastases, nor in overall survival. Hence in the era of prolonged survival with stage IV cancer, stereotactic radiosurgery is a reasonable alternative to whole brain radiation in order to minimize the impact of treatment upon quality of life without sacrificing overall survival.

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

    Science.gov (United States)

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

    2015-03-01

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

  1. Stereotactic radiosurgery in acoustic neurinomas

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    Yamamoto, Masaaki; Noren, G. (Karolinska Hospital, Stockholm (Sweden))

    1990-12-01

    The records of 57 patients with 61 acoustic neurinomas treated with stereotatic radiosurgery at the Karolinska Hospital, Stockholm, from 1982 through 1984, were reviewed. Adequate radiological and clinical follow-up evaluations were available in these cases. An additional 8 patients were treated during this same period but were not included because of insufficient data. The tumors were evaluated with CT or MRI. Their post-operative follow-up period was 6-66 months (mean 28 months). Decrease of tumor size or no change was considered as a response to radiosurgery. This was found in 54 (88%) of the tumors. Small tumors with a diameter of less than 15 mm responded better (93%) than large ones (85%). Ninety-five percent of unilateral tumors and 74% of tumors associated with neurofibromatosis responded well. Seven tumors had definite radiographic signs of subsequent growth. Four were removed using standard microsurgical tequniques and three have so far not required further treatment. Facial and trigeminal nerve function was evaluated in 58 facial surfaces where tumors had been irradiated. Transient facial weakness developed in 9% and facial hypesthesia in 9% of the irradiated cases. The onset of these nerve dysfunction appeared with a latency period of 4 to 15 months after radiosurgery. Excluding the ears which had been totally deaf before the treatment, forty-one ears were evaluated fully by audiometry prior to and one year after irradiation. 30% of them had no change in hearing, 68% had a more or less pronouced deterioration and 2% had improvement. We regard efficiency in arresting tumor growth without endangering life, preservation of facial nerve function, and only a day of hospitalization as major benefits of radiosurgery. (author).

  2. Stereotactic Radiosurgery (SRS) / Stereotactic body radiotherapy (SBRT): Benefit to Irish patients and Irish Healthcare Economy

    LENUS (Irish Health Repository)

    Cagney, DN

    2017-01-01

    Cancer incidence across Europe is projected to rise rapidly over the next decade. This rising cancer incidence is mirrored by increasing use of and indications for stereotactic radiation. This paper seeks to summarize the exponential increase in indications for stereotactic radiotherapy as well as the evolving economic advantages of stereotactic radiosurgery and stereotactic body radiotherapy

  3. Hypofractionated stereotactic radiotherapy for brain metastases. Results from three different dose concepts

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    Fahrig, A.; Grabenbauer, G.; Sauer, R. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center of the Univ. of Erlangen (Germany); Ganslandt, O. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center of the Univ. of Erlangen (Germany); Dept. of Neurosurgery of the Univ. of Erlangen (Germany); Lambrecht, U. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center of the Univ. of Erlangen (Germany); Div. of Medical Physics of the Dept. of Radiation Therapy of the Univ. of Erlangen (Germany); Kleinert, G.; Hamm, K. [Dept. for Stereotactic Neurosurgery and Radiosurgery, Helios Klinikum Erfurt (Germany)

    2007-11-15

    Purpose: To evaluate efficacy and toxicity of hypofractionated stereotactic radiotherapy (hfSRT) with three different dose concepts for irresectable brain metastases not amenable to radiosurgery (SRS) using non-invasive fixation of the skull. Patients and Methods: From 6/2000 to 6/2005, 150 patients with 228 brain metastases were treated at the dedicated stereotactic radiosurgery system Novalis trademark (BrainLAB, Feldkirchen, Germany) in two German treatment centers. Three different dose concepts were applied: 5 x 6-7 Gy (A: 72 brain metastases), 10 x 4 Gy (B: 59 brain metastases) and 7 x 5 Gy (C: 97 brain metastases). Median planning target volume (PTV) was 6.1 cm{sup 3} (range, 0.02-95.97). Results: Rates of complete remission (CR), partial remission (PR), no change (NC) and progressive disease (PD) were 42%, 30%, 21% and 7%, respectively (median follow-up 28 months). Median survival was 16 months. Survival at 6 and 12 months was 83% and 66%, respectively. Side effects were dependent on the PTV and on dose concept (median PTV in case of increasing edema or necrosis: 17 cm{sup 3}, A: 22%, C: 7%). HfSRT with 10 x 4 Gy (B) was well tolerated without side effects. Conclusion: Hypofractionated stereotactic radiotherapy is an effective and safe treatment. In case of brain metastases > 15 cm{sup 3} (diameter > 3 cm) and concerning toxicity, 10 x 4 Gy seem to be more advantageous than shorter fractionation with higher doses while 5 x 6-7 Gy and 7 x 5 Gy were followed by higher response rates. Further specification of tolerance doses and tolerance according to the different brain regions has to be done. (orig.)

  4. Inter- and intrafractional dose uncertainty in hypofractionated Gamma Knife radiosurgery.

    Science.gov (United States)

    Kim, Taeho; Sheehan, Jason; Schlesinger, David

    2016-03-08

    The purpose of this study is to evaluate inter- and intrafractional dose variations resulting from head position deviations for patients treated with the Extend relocatable frame system utilized in hypofractionated Gamma Knife radiosurgery (GKRS). While previous reports characterized the residual setup and intrafraction uncertainties of the system, the dosimetric consequences have not been investigated. A digital gauge was used to measure the head position of 16 consecutive Extend patients (62 fractions) at the time of simulation, before each fraction, and immediately following each fraction. Vector interfraction (difference between simulation and prefraction positions) and intrafraction (difference between postfraction and prefraction positions) shifts in patient position were calculated. Planned dose distributions were shifted by the offset to determine the time-of-treatment dose. Variations in mean and maximum target and organ at risk (OAR) doses as a function of positional shift were evaluated. The mean vector interfraction shift was 0.64 mm (Standard Deviation (SD): 0.25 mm, maximum: 1.17 mm). The mean intrafraction shift was 0.39 mm (SD: 0.25 mm, maximum: 1.44 mm). The mean variation in mean target dose was 0.66% (SD: 1.15%, maximum: 5.77%) for inter-fraction shifts and 0.26% (SD: 0.34%, maximum: 1.85%) for intrafraction shifts. The mean variation in maximum dose to OARs was 7.15% (SD: 5.73%, maximum: 30.59%) for interfraction shifts and 4.07% (SD: 4.22%, maximum: 17.04%) for intrafraction shifts. Linear fitting of the mean variation in maximum dose to OARs as a function of position yielded dose deviations of 10.58%/mm for interfractional shifts and 7.69%/mm for intrafractional shifts. Positional uncertainties when per-forming hypofractionated Gamma Knife radiosurgery with the Extend system are small and comparable to frame-based uncertainties (< 1 mm). However, the steep dose gradient characteristics of GKRS mean that the dosimetric consequences of

  5. Stereotactic radiosurgery for the treatment of brain metastases; results from a single institution experience.

    LENUS (Irish Health Repository)

    Burke, D

    2013-09-01

    Stereotactic radiosurgery is frequently used for the treatment of brain metastases. This study provides a retrospective evaluation of patients with secondary lesions of the brain treated with stereotactic radiosurgery (SRS) at our institution.

  6. Stereotactic radiosurgery for glioblastoma: retrospective analysis

    Directory of Open Access Journals (Sweden)

    Walter Kevin A

    2009-03-01

    Full Text Available Abstract Purpose This retrospective study was done to better understand the conditions for which stereotactic radiosurgery (SRS for glioblastoma may be efficacious. Methods Between 2000 and 2007, 33 patients with a pathological diagnosis of glioblastoma received SRS with the Novalis® Shaped Beam Radiosurgery system. Eighteen patients (54% underwent salvage SRS for recurrence while 15 (45% patients received upfront SRS following standard fractionated RT for newly diagnosed glioblastoma. Results There were no RTOG grade >2 acute side effects. The median survival after SRS was 6.7 months (range 1.4 – 74.7. There was no significant difference in overall survival (from the time of initial diagnosis with respect to the timing of SRS (p = 0.2. There was significantly better progression free survival in patients treated with SRS as consolidation versus at the time of recurrence (p = 0.04. The majority of patients failed within or at the margin of the SRS treatment volume (21/26 evaluable for recurrence. Conclusion SRS is well tolerated in the treatment of glioblastoma. As there was no difference in survival whether SRS is delivered upfront or at recurrence, the treatment for each patient should be individualized. Future studies are needed to identify patients most likely to respond to SRS.

  7. A new treatment method for brain diseases. Stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Shirato, Hiroki (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1994-01-01

    This paper deals with stereotactic radiosurgery, a novel medical treatment technique for brain diseases. It is the most sophisticated modality that allows the functional preservation. Recently, CT scan and MRI scan have dramatically changed the diagnostic accuracy of tumor localization in the brain. A device named stereotactic head fixation system makes it possible to localize deep-seated brain diseases with an accuracy of 1-1.5 mm. Using multiple convergent narrow beams of high-energy X-ray, a stereotactic head frame, and a three dimensional computer graphics of CT images, patients with deep-seated nidus can be treated without any complications. Normal tissues would not receive large doses but the center of the nidus is irradiated heavily because of the convergence of X-ray beams. Thus stereotactic radiosurgery is more accurate, effective, and less toxic than conventional radiotherapy and is safer and more effective than surgery for many brain diseases. Small arteriovenous malformation in the brain, which is a fetal disease, and small acoustic neurinomas, in which surgery often causes facial nerve palsy and hearing loss, are presented as good candidates for radiosurgery. For metastatic brain tumors, stereotactic radiosurgery makes such patients free from neurological symptoms, such as difficulty in walking and speaking, in a few days. (N.K.).

  8. Hypofractionated stereotactic radiotherapy for low grade glioma at McGill University: long-term follow-up.

    Science.gov (United States)

    Roberge, D; Souhami, L; Olivier, A; Leblanc, R; Podgorsak, E

    2006-02-01

    Small, well-defined, unresectable low-grade gliomas are attractive targets for stereotactic irradiation. Fractionated stereotactic irradiation of these targets has the theoretical benefit of increased normal tissue sparing beyond that provided by the physical characteristics of stereotactic radiosurgery. From July 1987 to November 1992, 21 patients were treated for low-grade glioma at our institution using a hypofractionated regimen of stereotactic radiotherapy. All patients had well-circumscribed, < 40 mm tumors. No patient had had prior radiotherapy. All lesions were histologically proven WHO grade I or II glial tumors. Lesions involved sensitive brain structures and were deemed unresectable. A typical dose of 42 Gy was delivered in 6 fractions over a two-week period using rigid immobilization and a linac-based dynamic stereotactic radiosurgical technique. Patients had a median age of 23 years (9-74) and were predominantly female (60%). Median tumor diameter was 20 mm. With a median follow-up for living patients of 13.3 years, the actuarial 5, 10, and 15-year overall survival rates are 76%, 71%, and 63%, respectively. Treatment was acutely well tolerated although three patients experienced late post-therapy complications. Our results and those of 241 patients treated in nine other institutional series are reviewed. Despite some examples of favorable short-term outcomes, all reported series are highly selected and thus likely biased. The data regarding the use of SRS is limited and, in our opinion, insufficient to claim a clear therapeutic advantage to SRS in the initial management of low-grade glioma. Our own results with hypofractionated stereotactic radiotherapy are similar to those expected with standard therapy.

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

    Directory of Open Access Journals (Sweden)

    Constine Louis S

    2008-10-01

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

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

    Science.gov (United States)

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

    2008-01-01

    Stereotactic body radiation (SBRT) is an emerging tool in radiation oncology in which the targeting accuracy is improved via the detection and processing of a three-dimensional coordinate system that is aligned to the target. With improved targeting accuracy, SBRT allows for the minimization of normal tissue volume exposed to high radiation dose as well as the escalation of fractional dose delivery. The goal of SBRT is to minimize toxicity while maximizing tumor control. This review will discuss the basic principles of SBRT, the radiobiology of hypofractionated radiation and the outcome from published clinical trials of SBRT, with a focus on late toxicity after SBRT. While clinical data has shown SBRT to be safe in most circumstances, more data is needed to refine the ideal dose-volume metrics. PMID:18976463

  11. Stereotactic Radiosurgery (SRS and Stereotactic Body Radiation Therapy (SBRT Cost-Effectiveness Results

    Directory of Open Access Journals (Sweden)

    Akash eBijlani

    2013-04-01

    Full Text Available Objective: To describe and synthesize the current stereotactic radiosurgery (SRS and stereotactic body radiation therapy (SBRT cost-effectiveness research to date across several common SRS and SBRT applications. Methods: This review was limited to comparative economic evaluations of SRS, SBRT and alternative treatments (e.g., other radiotherapy techniques or surgery. Based on PubMed searches using the terms, stereotactic, stereotactic radiosurgery, stereotactic radiotherapy, stereotactic body radiotherapy, stereotactic body radiation therapy, stereotactic ablative radiotherapy, economic evaluation, quality adjusted life year (QALY, cost, cost effectiveness, cost utility and cost analysis, published studies of cost-effectiveness and health economics were obtained. Included were articles in peer-reviewed journals that presented a comparison of costs between treatment alternatives from January 1997 to November 2012. Papers were excluded if they did not present cost calculations, therapeutic cost comparisons, or health economic endpoints. Results: Clinical outcomes and costs of SRS and SBRT were compared to other therapies for treatment of cancer in the brain, spine, lung, prostate and pancreas. Treatment outcomes for SRS and SBRT are usually superior or comparable, and cost-effective, relative to alternative techniques. Conclusion: Based on the review of current SRS and SBRT clinical and health economic literature, from a patient perspective, SRS and SBRT provide patients a clinically-effective treatment option, while from the payer and provider perspective, SRS and SBRT demonstrate cost-savings.

  12. The study on linac stereotactic radiosurgery for acoustic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Ohishi, Hitoshi [Toho Univ., Tokyo (Japan). School of Medicine

    1995-01-01

    We have designed and manufactured a new type of device for stereotactic radiosurgery characterized by the combined use of a rotatory chair and a linear accelerator. In this study, 20 acoustic tumors treated by our modality were evaluated by serial neuroimaging, neurofunctional outcome and, in a few cases, pathological findings of surgical specimens. Because tumor size usually changed very slowly after radiosurgery, 12 cases that had a minimum of 12 months of follow-up were employed in the analysis of tumor size. Serial neuroimaging studies revealed the reduction of tumor size in 3 cases and prevention of tumor growth in 7 cases, therefore, the rate of tumor control was evaluated as 83%. Growth of tumor size occurred in 3 cases, two were cases harbouring a large cyst in the tumor and another was a case of neurofibromatosis type 2. In 13 cases (68%), loss of the gadolinium enhancement effect inside the tumor was observed. This is a characteristic change after radiosurgery for acoustic tumors, and attributable to a necrotic change. Cranial nerve neuropathies as a complication also occurred (facial nerve palsy in 2 and trigeminal nerve dysfunction in 1). Adjacent parenchymal change appeared in 1 case. This patient had two prior operations and the tumor had an irregular shape, therefore, planning for radiosurgery encountered some difficulty. Hydrocephalus occurred in 1 case. Surgical specimens in 2 cases in which microsurgery was undertaken for growing tumors, revealed a necrotic tumor tissue and proliferation of fibrous tissue. In conclusion, our new device for stereotactic radiosurgery is particularly useful for the treatment of acoustic tumors. Similar therapeutic results of the gamma knife have been achieved. Radiosurgery is a recommendable treatment for acoustic tumors. However, the superiority of radiosurgery over microsurgery is still controversial and needs a longer term follow-up and multivariate analysis for a final conclusion. (author).

  13. The use of stereotactic radiosurgery in the management of meningiomas.

    Science.gov (United States)

    Malik, Irfan; Rowe, J G; Walton, L; Radatz, M W R; Kemeny, A A

    2005-02-01

    This is a systematic review of a consecutive series of 309 meningiomas treated with gamma knife stereotactic radiosurgery between 1994 and 2000. There was an extreme selection bias towards lesions unfavourable for surgery, determined by the patients referred for treatment: 70% of tumours involved the skull base, 47% specifically the cavernous sinus: 15% of patients had multiple meningiomatosis or type 2 neurofibromatosis. Tumour histology was the main determinant of growth control (p < 0.001), the 5-year actuarial control rates being 87% for typical meningiomas, 49% for atypical tumours and 0% for malignant lesions. Complications from radiosurgery were rare, occurring in 3% of tumours, and were most frequently trigeminal and eye movement disturbances treating cavernous sinus meningiomas. Given the problems inherent in managing these tumours, radiosurgery is a valuable strategy and adjuvant treatment for these meningiomas.

  14. Stereotactic Radiosurgery for Classical Trigeminal Neuralgia

    Directory of Open Access Journals (Sweden)

    Henry Kodrat

    2016-04-01

    Full Text Available Trigeminal neuralgia is a debilitating pain syndrome with a distinct symptom mainly excruciating facial pain that tends to come and go unpredictably in sudden shock-like attacks. Medical management remains the primary treatment for classical trigeminal neuralgia. When medical therapy failed, surgery with microvascular decompression can be performed. Radiosurgery can be offered for classical trigeminal neuralgia patients who are not surgical candidate or surgery refusal and they should not in acute pain condition. Radiosurgery is widely used because of good therapeutic result and low complication rate. Weakness of this technique is a latency period, which is time required for pain relief. It usually ranges from 1 to 2 months. This review enlightens the important role of radiosurgery in the treatment of classical trigeminal neuralgia.

  15. Stereotactic radiosurgery for intracranial lesions using a linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Shoji, Kazufusa [Mie Univ., Tsu (Japan). School of Medicine; Toyota, Shun; Seta, Hidetoshi [and others

    1996-09-01

    Experiences in 47 cases of stereotactic radiosurgery were reported. The surgery was carried out using stereotactic radiosurgery system of Fisher STP system (Leibinger Co.). The accelerator was Clinac 2100c (Varian Co., 10 mV X ray) or EXL-15 SP (Mitsubishi Co., 6 mV) equipped with collimator. CT and MRI imaging data were firstly transported to the working station to determine the target volume, target coordinates and radiation dose. Irradiation from 90deg to -90deg directions from isocenter of the linac was done within an error of 1 mm after the actual measurement of the target on the port film. The treatment was necessary for 6-8 hr and and irradiation was essentially complete for it. The dose was 20 Gy for metastatic brain tumors (31 patients), 14-16 Gy for acoustic neuroma (1) and 16 Gy for arteriovenous malformation (1). The local control rate of the brain tumors was as high as 90%. The complication was cerebral necrosis (1 case) and exacerbation of neurological symptoms (1), which exhibited remission with steroid treatment. Thus stereotactic radiosurgery with linac made it possible to treat intracranial lesions without invasion effectively and safely. (K.H.)

  16. Stereotactic diffusion tensor imaging tractography for Gamma Knife radiosurgery.

    Science.gov (United States)

    Gavin, Cormac G; Ian Sabin, H

    2016-12-01

    OBJECTIVE The integration of modern neuroimaging into treatment planning has increased the therapeutic potential and safety of stereotactic radiosurgery. The authors report their method of integrating stereotactic diffusion tensor imaging (DTI) tractography into conventional treatment planning for Gamma Knife radiosurgery (GKRS). The aim of this study was to demonstrate the feasibility of this technique and to address some of the technical limitations of previously reported techniques. METHODS Twenty patients who underwent GKRS composed the study cohort. They consisted of 1 initial test case (a patient with a vestibular schwannoma), 5 patients with arteriovenous malformations, 9 patients with cerebral metastases, 1 patient with parasagittal meningioma, and 4 patients with vestibular schwannoma. DT images were obtained at the time of standard GKRS protocol MRI (T1 and T2 weighted) for treatment, with the patient's head secured by a Leksell stereotactic frame. All studies were performed using a 1.5-T magnet with a single-channel head coil. DTI was performed with diffusion gradients in 32 directions and coregistered with the volumetric T1-weighted study. DTI postprocessing by means of commercially available software allowed tensor computation and the creation of directionally encoded color-, apparent diffusion coefficient-, and fractional anisotropy-mapped sequences. In addition, the software allowed visualized critical tracts to be exported as a structural volume and integrated into GammaPlan as an "organ at risk" during shot planning. Combined images were transferred to GammaPlan and integrated into treatment planning. RESULTS Stereotactic DT images were successfully acquired in all patients, with generation of correct directionally encoded color images. Tract generation with the software was straightforward and reproducible, particularly for axial tracts such as the optic radiation and the arcuate fasciculus. Corticospinal tract visualization was hampered by some

  17. Reproducibility and geometric accuracy of the fixster system during hypofractionated stereotactic radiotherapy

    Directory of Open Access Journals (Sweden)

    Henriksson Roger

    2008-05-01

    Full Text Available Abstract Background Hypofractionated radiotherapy has been used for the treatment of AVMs and brain metastases. Hypofractionation necessitates the use of a relocatable stereotactic frame that has to be applied on several occasions. The stereotactic frame needs to have a high degree of reproducibility, and patient positioning is crucial to achieve a high accuracy of the treatment. Methods In this study we have, by radiological means, evaluated the reproducibility of the isocenter in consecutive treatment sessions using the Fixster frame. Deviations in the X, Y and Z-axis were measured in 10 patients treated with hypofractionated radiotherapy. Results The mean deviation in the X-axis was 0.4 mm (range -2.1 – 2.1, median 0.7 mm and in the Y-axis -0.3 mm (range -1.4 – 0.7, median -0.2 mm. The mean deviation in the Z-axis was -0.6 (range -1.4 – 1.4, median 0.0 mm. Conclusion There is a high degree of reproducibility of the isocenter during successive treatment sessions with HCSRT using the Fixster frame for stereotactic targeting. The high reducibility enables a safe treatment using hypofractionated stereotactic radiotherapy.

  18. Stereotactic Radiosurgery and Fractionated Stereotactic Radiation Therapy for the Treatment of Uveal Melanoma.

    Science.gov (United States)

    Yazici, Gozde; Kiratli, Hayyam; Ozyigit, Gokhan; Sari, Sezin Yuce; Cengiz, Mustafa; Tarlan, Bercin; Mocan, Burce Ozgen; Zorlu, Faruk

    2017-05-01

    To evaluate treatment results of stereotactic radiosurgery or fractionated stereotactic radiation therapy (SRS/FSRT) for uveal melanoma. We retrospectively evaluated 181 patients with 182 uveal melanomas receiving SRS/FSRT between 2007 and 2013. Treatment was administered with CyberKnife. According to Collaborative Ocular Melanoma Study criteria, tumor size was small in 1%, medium in 49.5%, and large in 49.5% of the patients. Seventy-one tumors received treatment outcome was achieved using ≥45 Gy in 3 fractions. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Citation measures in stereotactic radiosurgery: publication across a discipline.

    Science.gov (United States)

    Kondziolka, Douglas

    2011-01-01

    It is possible to judge the impact of scientific research by the number of citations a publication has received. We identified the most cited works in the field of stereotactic radiosurgery to study the evolution of this field from the perspective of publication. A Web of Science search was performed for articles that included the word 'radiosurgery' in the title. We studied the reports with >100 citations. A total of 5,532 published works were available for study between 1951 and 2010. Eighty-five articles had ≥ 100 citations, and these were published in 19 separate journals. The majority were published in the International Journal of Radiation Oncology, Biology and Physics, the Journal of Neurosurgery and Neurosurgery. The most common topics included brain metastasis management (n = 20), arteriovenous malformations (n = 17), vestibular schwannomas (n = 9), technologies (n = 9), meningiomas (n = 8) and dose response/radiobiology (n = 6). Fifty-seven percent of the articles were published in the last 10 years. The first radiosurgery report by Leksell (1951) initiated the field. The 1980s were a period of new technology development followed in the 1990s by introductory articles on specific indications that consisted mainly of retrospective case series. More sophisticated higher level evidence reports were published in the last decade. The most significant works in radiosurgery include initial technology descriptions, multicenter studies with large numbers of patients, randomized clinical trials and reports that provide dose prescription guidelines. Copyright © 2011 S. Karger AG, Basel.

  20. Dose volume analysis in brachytherapy and stereotactic radiosurgery

    CERN Document Server

    Tozer-Loft, S M

    2000-01-01

    compared with a range of figures of merit which express different aspects of the quality of each dose distributions. The results are analysed in an attempt to answer the question: What are the important features of the dose distribution (conformality, uniformity, etc) which show a definite relationship with the outcome of the treatment? Initial results show positively that, when Gamma Knife radiosurgery is used to treat acoustic neuroma, some measures of conformality seem to have a surprising, but significant association with outcome. A brief introduction to three branches of radiotherapy is given: interstitial brachytherapy, external beam megavoltage radiotherapy, and stereotactic radiosurgery. The current interest in issues around conformity, uniformity and optimisation is explained in the light of technical developments in these fields. A novel method of displaying dose-volume information, which mathematically suppresses the inverse-square law, as first suggested by L.L. Anderson for use in brachytherapy i...

  1. Stereotactic radiosurgery for trigeminal neuralgia: outcomes and complications.

    Science.gov (United States)

    Loescher, Alison R; Radatz, Matthias; Kemeny, Andras; Rowe, Jeremy

    2012-02-01

    Stereotactic radiosurgery is one of a number of recognised treatments for the management of trigeminal neuralgia refractory to drug therapy. The reported success of stereotactic radiosurgery in managing patients with trigeminal neuralgia varies in different units from 22 to 75%. This paper reports the outcomes of patients with trigeminal neuralgia who were treated at the National Centre for Stereotactic Radiosurgery in Sheffield, UK. The study reports the outcome of 72 patients treated consecutively between October 2004 and May 2008. Data were collected prospectively by a postal questionnaire sent to patients at 6, 12 and 24 months after treatment. The median age was 65.6 years (39 males: 33 females). Fourteen patients had secondary trigeminal neuralgia (eight multiple sclerosis). Fifteen of the patients included in the study were receiving a second treatment (an initial treatment having improved their pain significantly for at least 6 months). All radiosurgical procedures were performed using a single 4 mm collimator isocenter covering the region of the dorsal root entry zone with a maximal radiation dose of 80 Gy. The percentage of patients defined as having an excellent outcome (pain free without medication) was 39% after 6 months, 36% after 12 months and 64% after 24 months. The percentage of patients who reported being very satisfied with treatment was 71% after 6 months, 57% after 12 months and 53% after 24 months. Half the patients with secondary trigeminal neuralgia were pain free without medication after treatment, and 60% of patients who underwent a second treatment were pain free. A new trigeminal sensory deficit was reported by 31% of patients after radiosurgical treatment.

  2. Novalis Stereotactic Radiosurgery for Spinal Dural Arteriovenous Fistula.

    Science.gov (United States)

    Sung, Kyoung-Su; Song, Young-Jin; Kim, Ki-Uk

    2016-07-01

    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.

  3. Hypofractionated stereotactic radiotherapy to the rat hippocampus. Determination of dose response and tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Ernst-Stecken, A.; Roedel, F.; Grabenbauer, G.; Sauer, R. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center; Jeske, I.; Bluemcke, I. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Neuropathology; Hess, A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Experimental and Clinical Pharmacology and Toxicology; Ganslandt, O. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Neurosurgery; Brune, K. [Erlangen-Nuernberg Univ., Erlangen (Germany). Doerenkamp Professor for Innovations in Animal and Consumer Protection

    2007-08-15

    Purpose: To determine the effect of hypofractionated stereotactic radiotherapy (hfSRT) on adult rat brain tissue (necrosis, impact on blood-brain barrier, signal changes on high-field magnetic resonance imaging [MRI]). Material and Methods: Adult male Wistar rats underwent MRI and CT scanning of the brain and respective images were introduced into the Novalis trademark radiosurgery device (BrainLab, Feldkirchen, Germany). All animals (body weight 350 g) were irradiated weekly with doses of 2 x 10 Gy (n = 3 animals), 3 x 10 Gy (n = 3 animals) and 4 x 10 Gy (n = 3 animals), targeted to the left hippocampus after image-guided positioning. 4.7-T T2-weighted MRI scanning was performed in each animal. Animals were sacrificed 8, 12, and 16 weeks after hfSRT and brains were immersion-fixed in 4% paraformaldehyde for subsequent histopathologic analysis. Results: In concordance with isodose distributions, pathologic signal hyperintensities in MRI were recorded from 4 x 10 Gy after 8 weeks, 3 x 10 Gy after 12 weeks, while 2 x 10 Gy induced slight detectable alterations only after 16 weeks. Subsequent histopathologic analysis revealed hippocampal cell necrosis with significantly earlier and stronger occurrence for higher doses (40 Gy > 30 Gy > 20 Gy). Pial microvessel permeability also increased after 40 Gy, whereas 30 Gy induced moderate changes. Conclusion: Conclusion: Partial-brain irradiation with hfSRT (Novalis trademark System) was successfully adopted for small animals and histopathologic analysis confirmed its repositioning accuracy. The neuropathologic effects correlated with dose and observation time. The approach will be further developed for quality assurance in hfSRT of normal brain tissue, as well as novel treatment modalities in epileptic rats and orthotopic tumor models. (orig.)

  4. Stereotactic radiosurgery for merkel cell carcinoma brain metastases.

    Science.gov (United States)

    Jacob, Arun T; Alexandru-Abrams, Daniela; Abrams, Eric M; Lee, John Y K

    2015-09-01

    In this report we propose a novel approach to treat merkel cell carcinoma (MCC) brain metastases and present a review of the literature in an attempt to establish a treatment algorithm and provide prognosis. MCC is a rare neuroendocrine malignancy affecting the aging population. This malignancy has a very aggressive behavior with frequent metastases. We report a 61-year-old man with a prior history of MCC who presented with diplopia. Brain MRI revealed a single right thalamic lesion consistent with metastasis. In the two weeks following GammaKnife stereotactic radiosurgery (Elekta, Stockholm, Sweden) the diplopia improved. A brain MRI demonstrated shrinkage of the tumor. From our literature search we found only six other patients with MCC brain metastases. The majority of these patients were treated with whole brain radiation in conjunction with chemotherapy. We propose that stereotactic radiosurgery can be used as a first line therapy for patients with MCC metastatic brain disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Stereotactic gamma radiosurgery of pineal and related tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Tatsuya; Mori, Yoshimasa; Yamada, Yasushi; Kida, Yoshihisa [Komaki City Hospital, Aichi (Japan). Gamma Knife Center

    2001-06-01

    The role of gamma radiosurgery as an additional therapy after conventional treatments for pineal and related tumors was studied in 30 out of 33 cases with a mean follow-up of 23.3 months. Overall results showed that complete response (CR) was obtained in 8 cases (26.7%) and response rate was 73.3%. However, enlargement of the tumors was noted in 8 cases, of which 7 (23.3%) died of tumor progression (PG). Germinomas and pineocytomas showed higher response and control rates of 100%, and no tumor enlargement or death occurred after gamma knife treatment. In germinoma with STGC (syncytiotrophoblastic giant cell) which has been thought to have intermediate prognosis, two cases showed partial response (PR), but another died from progression of the disease. Malignant germ cell tumors and pineoblastomas showed unfavorable response and prognosis; the response and progression rates were 50%. However, complete response was obtained in 3 cases (25%) after gamma radiosurgery. Gamma knife was the initial treatment in three cases without pathological diagnosis in which one obtained CR and two showed partial response (PR). Stereotactic gamma radiosurgery is expected to be an effective and novel treatment for pineal and related tumors not only as an adjuvant, but also as an initial therapy. (author)

  6. Dose volume analysis in brachytherapy and stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Tozer-Loft, S.M

    2000-12-01

    A brief introduction to three branches of radiotherapy is given: interstitial brachytherapy, external beam megavoltage radiotherapy, and stereotactic radiosurgery. The current interest in issues around conformity, uniformity and optimisation is explained in the light of technical developments in these fields. A novel method of displaying dose-volume information, which mathematically suppresses the inverse-square law, as first suggested by L.L. Anderson for use in brachytherapy is explained in detail, and some improvements proposed. These 'natural' histograms are extended to show the effects of real point sources which do not exactly follow the inverse-square law, and to demonstrate the in-target dose-volume distribution, previously unpublished. The histograms are used as a way of mathematically analysing the properties of theoretical mono-energetic radionuclides, and for demonstrating the dosimetric properties of a potential new brachytherapy source (Ytterbium-169). A new modification of the Anderson formalism is then described for producing Anderson Inverse-Square Shifted (AISS) histograms for the Gamma Knife, which are shown to be useful for demonstrating the quality of stereotactic radiosurgery dose distributions. A study is performed analysing the results of Gamma Knife treatments on 44 patients suffering from a benign brain tumour (acoustic neuroma). Follow-up data is used to estimate the volume shrinkage or growth of each tumour, and this measure of outcome is compared with a range of figures of merit which express different aspects of the quality of each dose distributions. The results are analysed in an attempt to answer the question: What are the important features of the dose distribution (conformality, uniformity, etc) which show a definite relationship with the outcome of the treatment? Initial results show positively that, when Gamma Knife radiosurgery is used to treat acoustic neuroma, some measures of conformality seem to have a surprising

  7. THE HISTORY OF STEREOTACTIC RADIOSURGERY DEVELOPMENT AND ITS ROLE IN THE TREATMENT OF BRAIN METASTASES

    National Research Council Canada - National Science Library

    O. T. Engel; A. V. Nazarenko

    2015-01-01

    Metastases of primary tumors to the brain develop in 20–40 % of cancer patients. Historical information about the origin and development of the stereotactic radiosurgery method are shown, including GammaKnife and CyberKnife...

  8. Stereotactic radiotherapy and radiosurgery in pediatric patients: analysis of indications and outcome

    DEFF Research Database (Denmark)

    Mirza, Bilal; Mønsted, Anne; Jensen, Josephine Harding

    2010-01-01

    We describe indications, outcomes, and risk profiles of fractionated stereotactic radiotherapy (SRT) and single fraction "radiosurgery" (SRS) in pediatric patients compared to the adult population and evaluate the causal role of SRS and SRT in inducing new neurological complications.......We describe indications, outcomes, and risk profiles of fractionated stereotactic radiotherapy (SRT) and single fraction "radiosurgery" (SRS) in pediatric patients compared to the adult population and evaluate the causal role of SRS and SRT in inducing new neurological complications....

  9. 10 CFR 35.655 - Five-year inspection for teletherapy and gamma stereotactic radiosurgery units.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Five-year inspection for teletherapy and gamma... Radiosurgery Units § 35.655 Five-year inspection for teletherapy and gamma stereotactic radiosurgery units. (a... and serviced during source replacement or at intervals not to exceed 5 years, whichever comes first...

  10. Low Incidence of Fatigue after Hypofractionated Stereotactic Body Radiation Therapy for Localized Prostate Cancer

    OpenAIRE

    Dash, Chiranjeev; Demas, Kristina; Uhm, Sunghae; Hanscom, Heather N; Kim, Joy S; Suy, Simeng; Davis, Kimberly M.; Sween, Jennifer; Collins, Sean; Lucile L Adams-Campbell

    2012-01-01

    Background: Fatigue is a common side effect of conventional prostate cancer radiation therapy. The increased delivery precision necessitated by the high dose per fraction of stereotactic body radiation therapy (SBRT) offers the potential of reduce target volumes and hence the exposure of normal tissues to high radiation doses. Herein, we examine the level of fatigue associated with SBRT treatment. Methods: Forty patients with localized prostate cancer treated with hypofractionated SBRT, and a...

  11. Low Incidence of Fatigue after Hypofractionated Stereotactic Body Radiation Therapy (SBRT) for Localized Prostate Cancer

    OpenAIRE

    Chiranjeev eDash; Kristina eDemas; Sunghae eUhm; Hanscom, Heather N; Kim, Joy S; Simeng eSuy; Davis, Kimberly M.; Jennifer eSween; Sean eCollins; Lucile L Adams-Campbell

    2012-01-01

    Background: Fatigue is a common side-effect of conventional prostate cancer radiation therapy. The increased delivery precision necessitated by the high dose per fraction of stereotactic body radiation therapy (SBRT) offers the potential of reduce target volumes and hence the exposure of normal tissues to high radiation doses. Herein, we examine the level of fatigue associated with SBRT treatment.Methods: Forty patients with localized prostate cancer treated with hypofractionated SBRT, an...

  12. Inception of a national multidisciplinary registry for stereotactic radiosurgery.

    Science.gov (United States)

    Sheehan, Jason P; Kavanagh, Brian D; Asher, Anthony; Harbaugh, Robert E

    2016-01-01

    Stereotactic radiosurgery (SRS) represents a multidisciplinary approach to the delivery of ionizing high-dose radiation to treat a wide variety of disorders. Much of the radiosurgical literature is based upon retrospective single-center studies along with a few randomized controlled clinical trials. More timely and effective evidence is needed to enhance the consistency and quality of and clinical outcomes achieved with SRS. The authors summarize the creation and implementation of a national SRS registry. The American Association of Neurological Surgeons (AANS) through NeuroPoint Alliance, Inc., started a successful registry effort with its lumbar spine initiative. Following a similar approach, the AANS and NeuroPoint Alliance collaborated with corporate partners and the American Society for Radiation Oncology to devise a data dictionary for an SRS registry. Through administrative and financial support from professional societies and corporate partners, a framework for implementation of the registry was created. Initial plans were devised for a 3-year effort encompassing 30 high-volume SRS centers across the country. Device-specific web-based data-extraction platforms were built by the corporate partners. Data uploaders were then used to port the data to a common repository managed by Quintiles, a national and international health care trials company. Audits of the data for completeness and veracity will be undertaken by Quintiles to ensure data fidelity. Data governance and analysis are overseen by an SRS board comprising equal numbers of representatives from the AANS and NeuroPoint Alliance. Over time, quality outcome assessments and post hoc research can be performed to advance the field of SRS. Stereotactic radiosurgery offers a high-technology approach to treating complex intracranial disorders. Improvements in the consistency and quality of care delivered to patients who undergo SRS should be afforded by the national registry effort that is underway.

  13. International Spine Radiosurgery Consortium Consensus Guidelines for Target Volume Definition in Spinal Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Brett W., E-mail: coxb@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Spratt, Daniel E. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Lovelock, Michael [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Bilsky, Mark H. [Department of Surgery, Division of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Lis, Eric [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ryu, Samuel [Department of Radiation Oncology, Henry Ford Hospital, Detroit, Michigan (United States); Sheehan, Jason [Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Gerszten, Peter C. [Department of Neurological Surgery and Radiation Oncology, University of Pittsburgh Medical Center, UPMC Presbyterian, Pittsburgh, Pennsylvania (United States); Chang, Eric [Department of Radiation Oncology, University of Southern California Keck School of Medicine, Health Sciences Campus, Los Angeles, California (United States); Gibbs, Iris; Soltys, Scott [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Sahgal, Arjun [Department of Radiation Oncology, Princess Margaret Hospital and the Sunnybrook Health Sciences Center, University of Toronto, Toronto, Ontario (Canada); Deasy, Joe [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Flickinger, John; Quader, Mubina [Department of Radiation Oncology, University of Pittsburgh Medical Center, UPMC Presbyterian, Pittsburgh, Pennsylvania (United States); Mindea, Stefan [Department of Neurosurgery, Stanford University School of Medicine, Stanford, California (United States); and others

    2012-08-01

    Purpose: Spinal stereotactic radiosurgery (SRS) is increasingly used to manage spinal metastases. However, target volume definition varies considerably and no consensus target volume guidelines exist. This study proposes consensus target volume definitions using common scenarios in metastatic spine radiosurgery. Methods and Materials: Seven radiation oncologists and 3 neurological surgeons with spinal radiosurgery expertise independently contoured target and critical normal structures for 10 cases representing common scenarios in metastatic spine radiosurgery. Each set of volumes was imported into the Computational Environment for Radiotherapy Research. Quantitative analysis was performed using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE) with kappa statistics calculating agreement between physicians. Optimized confidence level consensus contours were identified using histogram agreement analysis and characterized to create target volume definition guidelines. Results: Mean STAPLE agreement sensitivity and specificity was 0.76 (range, 0.67-0.84) and 0.97 (range, 0.94-0.99), respectively, for gross tumor volume (GTV) and 0.79 (range, 0.66-0.91) and 0.96 (range, 0.92-0.98), respectively, for clinical target volume (CTV). Mean kappa agreement was 0.65 (range, 0.54-0.79) for GTV and 0.64 (range, 0.54-0.82) for CTV (P<.01 for GTV and CTV in all cases). STAPLE histogram agreement analysis identified optimal consensus contours (80% confidence limit). Consensus recommendations include that the CTV should include abnormal marrow signal suspicious for microscopic invasion and an adjacent normal bony expansion to account for subclinical tumor spread in the marrow space. No epidural CTV expansion is recommended without epidural disease, and circumferential CTVs encircling the cord should be used only when the vertebral body, bilateral pedicles/lamina, and spinous process are all involved or there is extensive metastatic

  14. THE HISTORY OF STEREOTACTIC RADIOSURGERY DEVELOPMENT AND ITS ROLE IN THE TREATMENT OF BRAIN METASTASES

    Directory of Open Access Journals (Sweden)

    O. T. Engel

    2015-01-01

    Full Text Available  Metastases of primary tumors to the brain develop in 20–40 % of cancer patients. Historical information about the origin and development of the stereotactic radiosurgery method are shown, including GammaKnife and CyberKnife. The development of new centers of radiosurgery in the world makes the method more accessible for patients. The article examines the modern treatment algorithm for cerebral metastases and the place of stereotactic radiosurgery as a high-dose conformal ablative treatment of selected metastatic lesions in the management of these patients. It is shown that radiosurgery provides a high level of local control and survival, similar to surgical resection.The results of trails with combination of the stereotactic radiosurgery and total brain radiation therapy in patients with solitary and multiple lesions are reported. It is shown that the radiosurgery allows to avoid total irradiation in case of solitary metastasis, and also in case of multiple lesions, without affecting the survival. That, probably, helps to preserve neurocognitive function and quality of life for patients with good performance status according to Karnofsky scale (index ³ 70. We also discuss the possibility of stereotactic irradiation of postoperative cavity. The concept of radiosurgery is not divided upon the treatment platform.

  15. Volume growth rate of acoustic neuromas on MRI post-stereotactic radiosurgery

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    To, S.Y.; Lufkin, R.B.; Rand, R.; Robinson, J.D.; Hanafee, W.

    1990-01-01

    Of the approximately 160 acoustic neuroma patients treated with stereotactic radiosurgery in the world up to 1987, 8 patients at UCLA Medical Center have had two or more magnetic resonance scans at least one year apart available for study (all 8 patients were treated with stereotactic radiosurgery for acoustic neuromas by the Department of Neurosurgery at the Karolinska Hospital, Stockholm, Sweden). The followup time after radiosurgery ranged from 4 to 8 years. The volume doubling rate post-stereotactic radiosurgery was calculated to be slow (763 to 888 days) in two patients, virtually arrested in five patients (doubling times larger than 2500 days) and negative (-563 days) in one patient indicating a shrinking tumor. Due to the limited sample size no radiological finding or clinical data correlated with the volume doubling times. A control patient that had no treatment for her tumor had a doubling time of 217 days for comparison.

  16. Stereotactic radiosurgery for acoustic neuroma: a Canadian perspective

    Energy Technology Data Exchange (ETDEWEB)

    Ross, I.B. [Univ. of Manitoba, Section of Neurosurgery, Winnipeg, MB (Canada); Tator, C.H. [Univ. of Toronto, Div. of Neurosurgery, Toronto, Ontario (Canada)

    1998-11-01

    Stereotactically delivered radiation is now an accepted treatment for patients with acoustic neuroma. In some cases, patient preference may be the reason for its selection, while in others neurosurgeons may select it for patients who are elderly or have significant risk factors for conventional surgery. The majority of patients with acoustic neuroma treatment with stereotactic radiosurgery have been treated with the Gamma Knife, with follow ups of over 25 years in some instances. Other radiosurgical modalities utilizing the linear accelerator have been developed and appear promising, but there is no long-term: follow up. Canada does not possess a Gamma Knife facility, and its government-funded hospital and medical insurance agencies have made it difficult for patients to obtain reimbursement for Gamma Knife treatments in other countries. We review the literature to date on the various forms of radiation treatment for acoustic neuroma and discuss the current issues facing physicians and patients in Canada who wish to obtain their treatment of choice. (author)

  17. Hypofractionated stereotactic radiotherapy for primary and secondary intrapulmonary tumors. First results of a phase I/II study

    Energy Technology Data Exchange (ETDEWEB)

    Ernst-Stecken, A.; Sauer, R.; Grabenbauer, G. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center, Univ. Hospital Erlangen (Germany); Lambrecht, U.; Mueller, R. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center, Univ. Hospital Erlangen (Germany); Div. of Medical Physics, Dept. of Radiation Therapy, Univ. Hospital Erlangen (Germany)

    2006-12-15

    Purpose: to evaluate the feasibility, efficacy, and side effects of dose escalation in hypofractionated stereotactic radiotherapy (hfSRT) for intrapulmonary tumors with the Novalis trademark system (BrainLAB AG, Heimstetten, Germany). Patients and methods: from 07/2003 to 01/2005, 21 patients/39 tumors were treated with 5 x 7 Gy (n = 21; total dose 35 Gy) or 5 x 8 Gy (n = 18; total dose 40 Gy). There were three cases of primary lung cancer, the remainder were metastases. Median gross tumor volume (GTV) and planning target volume (PTV) were 2.89 cm{sup 3} (range, 0.15-67.94 cm{sup 3}) and 25.75 cm{sup 3} (range, 7.18-124.04 cm{sup 3}), respectively. Results: rates of complete remission, partial remission, no change, and progressive disease were 51%, 33%, 3%, and 13%, respectively. No grade 4 toxicity occurred, nearly all patients had grade 1 initially. One grade 3 toxicity, i.e., dyspnea, was documented for a period of 6 months after therapy. Radiosurgery quality assurance guidelines could be met. Conclusion: hfSRT of primary and secondary lung tumors using a schedule of five fractions at 7-8 Gy each was well tolerated. Further dose escalation is planned. (orig.)

  18. Radiosurgery of small skull-base lesions. No advantage for intensity-modulated stereotactic radiosurgery versus conformal arc technique

    Energy Technology Data Exchange (ETDEWEB)

    Ernst-Stecken, A.; Sauer, R.; Grabenbauer, G. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center, Univ. of Erlangen-Nuremberg, Erlangen (Germany); Lambrecht, U.; Mueller, R. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center, Univ. of Erlangen-Nuremberg, Erlangen (Germany); Div. of Medical Physics, Dept. of Radiation Therapy, Univ. of Erlangen-Nuremberg, Erlangen (Germany); Ganslandt, O.; Fahlbusch, R. [Dept. of Neurosurgery, Univ. of Erlangen-Nuremberg, Erlangen (Germany)

    2005-05-01

    Background and purpose: intensity-modulated stereotactic radiotherapy (IMSRT) has shown the ability to conform the dose to concavities and to better avoid critical organs for large tumors. Given the availability of an electronically driven micro-multileaf collimator, both intensity-modulated stereotactic radiosurgery (IMSRS) and dynamic conformal arc (DCA) technique (DCA) can be performed at the Novalis Shaped Beam Surgery Center, University of Erlangen-Nuremberg, Germany, since 12/2002. This study evaluates both techniques in small skull-base tumors treated with radiosurgery. Material and methods: between 12/2002 and 04/2004, a total of 109 radiosurgical procedures were performed in 77 patients, equally distributed between patients with acoustic neuroma (AN), pituitary adenoma (PA) and meningeoma (M). Six index patients (n = 2 AN, n = 1 PA, n = 3 M) routinely planned for dynamic arc stereotactic radiosurgery were replanned using the IMSRS approach (BrainScan, BrainLAB, Heimstetten, Germany). The RTOG radiosurgery quality assurance guidelines, isodose volumes, doses to organs at risk (OAR), and dose delivery criteria were compared. Results: DCA was superior to IMSRS for homogeneity and coverage. IMSRS could keep the high-dose-irradiated volumes (90% isodose volume) lower than DCA in the PA and AN with very small volumes, but all other lower dose volumes were larger for IMSRS. Dose maxima to OAR were higher for IMSRS. Treatment delivery time for IMSRS would clearly exceed treatment time for DCA by a factor of 2-3. The integral absorbed dose to the brain was much higher in the IMSRS than in the DCA approach (factor 2-3). Conclusion: RTOG radiosurgery guidelines were best met by the DCA rather than IMSRS approach for the treatment of small skull-base lesions. The IMSRS approach will increase the time for planning, dose delivery and integral dose to the brain. Thus, IMSRT techniques are recommended for fractionated stereotactic radiotherapy to larger volumes rather

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

    Science.gov (United States)

    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 (P0.05) 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%, (P0.05). Compared with conventional fractionated radiation therapy, image-guided hypofractionated stereotactic radiotherapy in NSCLC received better treatment efficacy and showed good tolerability. PMID:27574441

  20. Clinical and pathological changes in cerebral arteriovenous malformations after stereotactic radiosurgery failure

    Institute of Scientific and Technical Information of China (English)

    LIU Wei-ming; YE Xun; ZHAO Yuan-li; WANG Shuo; ZHAO Ji-zong

    2008-01-01

    Background Stereotactic radiosurgery is an alternative to resection of intracraniaI cerebral arteriovenous malformations (AVMs),while it will failin some cases.This study aimed to evaluate the changes after stereotactic radiosurgery for AVMs.Methods Nineteen cases with cerebral AVMs had failure after stereotactic radiosurgery therapy.The symptoms and angiography were assessed.All patients underwent microsurgery.Pathologic examination was performed for all cases and electron microscopic examination was carried out in 6 patients.Reaults Seven cases had hemorrhage from 12 to 98 months after stereotactic radiosurgery,5 had headache.4 had refractory encephalon edema,2 had epilepsy as a new symptom and 1 had a pressure cyst 5 years after radiosurgery.Angiography in 18 cases,8-98 months after radiation therapy,demonstrated no significant changes in 5 cases.slight reduction in 9,near complete obliteration in 1 and complete obliteration in 3.An abnormal vessel was found on pathologic examination in 17 cases,even one case had obliterated in angiography.Electron microscopy examination showed vessel wall weakness,but the vessels remained open and blood circulated.One case died because of a moribund state before surgery.The other 18 cases had no new neurological deficiencies,seizure control and no hemorrhage occurred after microsurgery at an average follow-up of 3 years.Conclusion Stereotactic radiotherapy for AVMs should have a long period follow-up.If serious complications occur,microsurgery can be performed as salvage treatment.

  1. Outcomes of treatment with stereotactic radiosurgery or proton beam therapy for choroidal melanoma.

    Science.gov (United States)

    Sikuade, M J; Salvi, S; Rundle, P A; Errington, D G; Kacperek, A; Rennie, I G

    2015-09-01

    To present our experience of the use of stereotactic radiosurgery and proton beam therapy to treat posterior uveal melanoma over a 10 year period. Case notes of patients treated with stereotactic radiosurgery (SRS), or Proton beam therapy (PBT) for posterior uveal melanoma were reviewed. Data collected included visual acuity at presentation and final review, local control rates, globe retention and complications. We analysed post-operative visual outcomes and if visual outcomes varied with proximity to the optic nerve or fovea. 191 patients were included in the study; 85 and 106 patients received Stereotactic radiosurgery and Proton beam therapy, respectively. Mean follow up period was 39 months in the SRS group and 34 months in the PBT group. Both treatments achieved excellent local control rates with eye retention in 98% of the SRS group and 95% in the PBT group. The stereotactic radiosurgery group showed a poorer visual prognosis with 65% losing more than 3 lines of Snellen acuity compared to 45% in the PBT group. 33% of the SRS group and 54% of proton beam patients had a visual acuity of 6/60 or better. Stereotactic radiosurgery and proton beam therapy are effective treatments for larger choroidal melanomas or tumours unsuitable for plaque radiotherapy. Our results suggest that patients treated with proton beam therapy retain better vision post-operatively; however, possible confounding factors include age, tumour location and systemic co-morbidities. These factors as well as the patient's preference should be considered when deciding between these two therapies.

  2. A pilot study of intensity modulated radiation therapy with hypofractionated stereotactic body radiation therapy (SBRT) boost in the treatment of intermediate- to high-risk prostate cancer.

    Science.gov (United States)

    Oermann, Eric K; Slack, Rebecca S; Hanscom, Heather N; Lei, Sue; Suy, Simeng; Park, Hyeon U; Kim, Joy S; Sherer, Benjamin A; Collins, Brian T; Satinsky, Andrew N; Harter, K William; Batipps, Gerald P; Constantinople, Nicholas L; Dejter, Stephen W; Maxted, William C; Regan, James B; Pahira, John J; McGeagh, Kevin G; Jha, Reena C; Dawson, Nancy A; Dritschilo, Anatoly; Lynch, John H; Collins, Sean P

    2010-10-01

    Clinical data suggest that large radiation fractions are biologically superior to smaller fraction sizes in prostate cancer radiotherapy. The CyberKnife is an appealing delivery system for hypofractionated radiosurgery due to its ability to deliver highly conformal radiation and to track and adjust for prostate motion in real-time. We report our early experience using the CyberKnife to deliver a hypofractionated stereotactic body radiation therapy (SBRT) boost to patients with intermediate- to high-risk prostate cancer. Twenty-four patients were treated with hypofractionated SBRT and supplemental external radiation therapy plus or minus androgen deprivation therapy (ADT). Patients were treated with SBRT to a dose of 19.5 Gy in 3 fractions followed by intensity modulated radiation therapy (IMRT) to a dose of 50.4 Gy in 28 fractions. Quality of life data were collected with American Urological Association (AUA) symptom score and Expanded Prostate Cancer Index Composite (EPIC) questionnaires before and after treatment. PSA responses were monitored; acute urinary and rectal toxicities were assessed using Common Toxicity Criteria (CTC) v3. All 24 patients completed the planned treatment with an average follow-up of 9.3 months. For patients who did not receive ADT, the median pre-treatment PSA was 10.6 ng/ml and decreased in all patients to a median of 1.5 ng/ml by 6 months post-treatment. Acute effects associated with treatment included Grade 2 urinary and gastrointestinal toxicity but no patient experienced acute Grade 3 or greater toxicity. AUA and EPIC scores returned to baseline by six months post-treatment. Hypofractionated SBRT combined with IMRT offers radiobiological benefits of a large fraction boost for dose escalation and is a well tolerated treatment option for men with intermediate- to high-risk prostate cancer. Early results are encouraging with biochemical response and acceptable toxicity. These data provide a basis for the design of a phase II clinical

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

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, Grant K.; Suh, John H.; Reuther, Alwyn M. [Department of Radiation Oncology, Cleveland Clinic, Cleveland, OH (United States); Vogelbaum, Michael A.; Barnett, Gene H.; Angelov, Lilyana; Weil, Robert J. [Department of Neurosurgery, Cleveland Clinic, Cleveland, OH (United States); Neyman, Gennady [Department of Radiation Oncology, Cleveland Clinic, Cleveland, OH (United States); Chao, Samuel T., E-mail: chaos@ccf.org [Department of Radiation Oncology, Cleveland Clinic, Cleveland, OH (United States)

    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

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

    OpenAIRE

    Constine Louis S; Milano Michael T; Okunieff Paul

    2008-01-01

    Abstract Stereotactic body radiation (SBRT) is an emerging tool in radiation oncology in which the targeting accuracy is improved via the detection and processing of a three-dimensional coordinate system that is aligned to the target. With improved targeting accuracy, SBRT allows for the minimization of normal tissue volume exposed to high radiation dose as well as the escalation of fractional dose delivery. The goal of SBRT is to minimize toxicity while maximizing tumor control. This review ...

  5. Effect of spine hardware on small spinal stereotactic radiosurgery dosimetry

    Science.gov (United States)

    Wang, Xin; Yang, James N.; Li, Xiaoqiang; Tailor, Ramesh; Vassilliev, Oleg; Brown, Paul; Rhines, Laurence; Chang, Eric

    2013-10-01

    Monte Carlo (MC) modeling of a 6 MV photon beam was used to study the dose perturbation from a titanium rod 5 mm in diameter in various small fields range from 2 × 2 to 5 × 5 cm2. The results showed that the rod increased the dose to water by ˜6% at the water-rod interface because of electron backscattering and decreased the dose by ˜7% in the shadow of the rod because of photon attenuation. The Pinnacle3 treatment planning system calculations matched the MC results at the depths more than 1 cm past the rod when the correct titanium density of 4.5 g cm-3 was used, but significantly underestimated the backscattering dose at the water-rod interface. A CT-density table with a top density of 1.82 g cm-3 (cortical bone) is a practical way to reduce the dosimetric error from the artifacts by preventing high density assignment to them, but can underestimates the attenuation by the titanium rod by 6%. However, when multi-beam with intensity modulation is used in actual patient spinal stereotactic radiosurgery treatment, the dosimetric effect of assigning 4.5 instead of 1.82 g cm-3 to titanium implants is complicated. It ranged from minimal effect to 2% dose difference affecting 15% target volume in the study. When hardware is in the beam path, density override to the titanium hardware is recommended.

  6. Stereotactic radiosurgery for intracranial arteriovenous malformations: A review

    Directory of Open Access Journals (Sweden)

    Ranjith K Moorthy

    2015-01-01

    Full Text Available 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Roos, Daniel E., E-mail: daniel.roos@health.sa.gov.au [Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, South Australia (Australia); University of Adelaide School of Medicine, Adelaide, South Australia (Australia); Potter, Andrew E. [Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, South Australia (Australia); Brophy, Brian P. [Department of Neurosurgery, Royal Adelaide Hospital, Adelaide, South Australia (Australia); University of Adelaide School of Medicine, Adelaide, South Australia (Australia)

    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.

  8. Stereotactic radiosurgery in hemangioblastoma: Experience over 14 years

    Directory of Open Access Journals (Sweden)

    Nishant Goyal

    2016-01-01

    Full Text Available Background: Although gamma knife has been advocated for hemangioblastomas, it is not used widely by neurosurgeons. Objective: We review our experience over 14 years in an attempt to define the role of stereotactic radiosurgery (SRS in the management of hemangioblastomas. Patients and Methods: A retrospective study was conducted on all patients of hemangioblastoma who underwent SRS at our institute over a period of 14 years (1998–2011. Gamma knife plans, clinical history, and radiology were reviewed for all patients. Results: A total of 2767 patients underwent gamma knife during the study period. Of these, 10 (0.36% patients were treated for 24 hemangioblastomas. Eight patients (80% had von Hippel-Lindau disease while two had sporadic hemangioblastomas. The median peripheral dose (50% isodose delivered to the tumors was 29.9 Gy. Clinical and radiological follow-up data were available for eight patients. Of these, two were re-operated for persisting cerebellar symptoms. The remaining six patients were recurrence-free at a mean follow-up of 48 months (range 19–108 months. One patient had an increase in cyst volume along with a decrease in the size of the mural nodule. Conclusions: SRS should be the first option for asymptomatic hemangioblastomas. Despite the obvious advantages, gamma knife is not widely used as an option for hemangioblastomas.

  9. Stereotactic radiosurgery for idiopathic glossopharyngeal neuralgia: an international multicenter study.

    Science.gov (United States)

    Kano, Hideyuki; Urgosik, Dusan; Liscak, Roman; Pollock, Bruce E; Cohen-Inbar, Or; Sheehan, Jason P; Sharma, Mayur; Silva, Danilo; Barnett, Gene H; Mathieu, David; Sisterson, Nathaniel D; Lunsford, L Dade

    2016-12-01

    OBJECTIVE The goal of this study was to evaluate the outcomes of Gamma Knife stereotactic radiosurgery (SRS) when used for patients with intractable idiopathic glossopharyngeal neuralgia. METHODS Six participating centers of the International Gamma Knife Research Foundation identified 22 patients who underwent SRS for intractable glossopharyngeal neuralgia between 1998 and 2015. The median patient age was 60 years (range 34-83 years). The median duration of symptoms before SRS was 46 months (range 1-240 months). Three patients had unsuccessful prior surgical procedures, including microvascular decompression (MVD) (n = 2) and balloon compression (n = 1). The radiosurgical target was the glossopharyngeal meatus. The median maximum dose was 80 Gy. RESULTS The median follow-up was 45 months after SRS (range 6-120 months). Twelve patients (55%) had neuralgia provided lasting pain reduction in 55% of patients after 1 or 2 SRS procedures. Patients who had a poor response or pain recurrence may require additional procedures such as repeat SRS, MVD, nerve blocks, or nerve section. No patient developed changes in vocal cord function or swallowing disorders after SRS in this study.

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

    Science.gov (United States)

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

    2016-01-01

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

  11. Maximum kinetic energy considerations in proton stereotactic radiosurgery.

    Science.gov (United States)

    Sengbusch, Evan R; Mackie, Thomas R

    2011-04-12

    The purpose of this study was to determine the maximum proton kinetic energy required to treat a given percentage of patients eligible for stereotactic radiosurgery (SRS) with coplanar arc-based proton therapy, contingent upon the number and location of gantry angles used. Treatment plans from 100 consecutive patients treated with SRS at the University of Wisconsin Carbone Cancer Center between June of 2007 and March of 2010 were analyzed. For each target volume within each patient, in-house software was used to place proton pencil beam spots over the distal surface of the target volume from 51 equally-spaced gantry angles of up to 360°. For each beam spot, the radiological path length from the surface of the patient to the distal boundary of the target was then calculated along a ray from the gantry location to the location of the beam spot. This data was used to generate a maximum proton energy requirement for each patient as a function of the arc length that would be spanned by the gantry angles used in a given treatment. If only a single treatment angle is required, 100% of the patients included in the study could be treated by a proton beam with a maximum kinetic energy of 118 MeV. As the length of the treatment arc is increased to 90°, 180°, 270°, and 360°, the maximum energy requirement increases to 127, 145, 156, and 179 MeV, respectively. A very high percentage of SRS patients could be treated at relatively low proton energies if the gantry angles used in the treatment plan do not span a large treatment arc. Maximum proton kinetic energy requirements increase linearly with size of the treatment arc.

  12. Stereotactic Radiosurgery for Recurrent or Unresectable Pilocytic Astrocytoma

    Energy Technology Data Exchange (ETDEWEB)

    Hallemeier, Christopher L. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Pollock, Bruce E. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Department of Neurological Surgery, Mayo Clinic, Rochester, MN (United States); Schomberg, Paula J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Link, Michael J. [Department of Neurological Surgery, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Stafford, Scott L., E-mail: Stafford.scott@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

    2012-05-01

    Purpose: To report the outcomes in patients with recurrent or unresectable pilocytic astrocytoma (PA) treated with Gamma Knife stereotactic radiosurgery (SRS). Methods and Materials: Retrospective review of 18 patients (20 lesions) with biopsy-confirmed PA having SRS at our institution from 1992 through 2005. Results: The median patient age at SRS was 23 years (range, 4-56). Thirteen patients (72%) had undergone one or more previous surgical resections, and 10 (56%) had previously received external-beam radiation therapy (EBRT). The median SRS treatment volume was 9.1 cm{sup 3} (range, 0.7-26.7). The median tumor margin dose was 15 Gy (range, 12-20). The median follow-up was 8.0 years (range, 0.5-15). Overall survival at 1, 5, and 10 years after SRS was 94%, 71%, and 71%, respectively. Tumor progression (local solid progression, n = 4; local solid progression + distant, n = 1; distant, n = 2; cyst development/progression, n = 4) was noted in 11 patients (61%). Progression-free survival at 1, 5, and 10 years was 65%, 41%, and 17%, respectively. Prior EBRT was associated with inferior overall survival (5-year risk, 100% vs. 50%, p = 0.03) and progression-free survival (5-year risk, 71% vs. 20%, p = 0.008). Nine of 11 patients with tumor-related symptoms improved after SRS. Symptomatic edema after SRS occurred in 8 patients (44%), which resolved with short-term corticosteroid therapy in the majority of those without early disease progression. Conclusions: SRS has low permanent radiation-related morbidity and durable local tumor control, making it a meaningful treatment option for patients with recurrent or unresectable PA in whom surgery and/or EBRT has failed.

  13. Proton Stereotactic Radiosurgery for the Treatment of Benign Meningiomas

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    Halasz, Lia M., E-mail: lhalasz@partners.org [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Bussiere, Marc R.; Dennis, Elizabeth R.; Niemierko, Andrzej [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Chapman, Paul H. [Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Loeffler, Jay S.; Shih, Helen A. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States)

    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.

  14. Adverse radiation effect after stereotactic radiosurgery for brain metastases : incidence, time course, and risk factors

    NARCIS (Netherlands)

    Sneed, Penny K.; Mendez, Joe; Vemer-van den Hoek, Johanna; Seymour, Zachary A.; Ma, Lijun; Molinaro, Annette M.; Fogh, Shannon E.; Nakamura, Jean L.; McDermott, Michael W.

    OBJECT The authors sought to determine the incidence, time course, and risk factors for overall adverse radiation effect (ARE) and symptomatic ARE after stereotactic radiosurgery (SRS) for brain metastases. METHODS All cases of brain metastases treated from 1998 through 2009 with Gamma Knife SRS at

  15. SU-E-T-642: Safety Procedures for Error Elimination in Cyberknife Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT)

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, A; Alkafi, A; Al-Najjar, W; Moftah, B [King Faisal Specialist Hospital and Research Center, Department of Biomedical Physics, Riyadh (Saudi Arabia)

    2014-06-15

    Purpose: Cyberknife system is used for providing stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) hypofractionation scheme. The whole treatment delivery is based on live imaging of the patient. The minor error made at any stage may bring severe radiation injury to the patient or damage to the system itself. Several safety measures were taken to make the system safer. Methods: The radiation treatment provided thru a 6MV linac attached to Kuka robot (Cyberknife G4, Accuray Inc. Sunnyvale, CA, USA). Several possible errors were identified related to patient alignment, treatment planning, dose delivery and physics quality assurance. During dose delivery, manual and visual checks were introduced to confirm pre and intra-treatment imaging to reduce possible errors. One additional step was introduced to confirm that software tracking-tools had worked correctly with highest possible confidence level. Robotic head move in different orientations over and around the patient body, the rigidity of linac-head cover and other accessories was checked periodically. The vender was alerted when a tiny or bigger piece of equipment needed additional interlocked support. Results: As of our experience treating 525 patients on Cyberknife during the last four years, we saw on and off technical issues. During image acquisition, it was made essential to follow the site-specific imaging protocols. Adequate anatomy was contoured to document the respective doses. Followed by auto-segmentation, manual tweaking was performed on every structure. The calculation box was enclosing the whole image during the final calculation. Every plan was evaluated on slice-by slice basis. To review the whole process, a check list was maintained during the physics 2nd-check. Conclusion: The implementation of manual and visual additional checks introduced along with automated checks for confirmation was found promising in terms of reduction in systematic errors and making the system

  16. Treatment options for von Hippel-Lindau's haemangioblastomatosis: the role of gamma knife stereotactic radiosurgery.

    Science.gov (United States)

    Rajaraman, C; Rowe, J G; Walton, L; Malik, I; Radatz, M; Kemeny, A A

    2004-08-01

    Haemangioblastomas secondary to von Hippel-Lindau (VHL) disease can be difficult to manage surgically, which has lead to an interest in the use of stereotactic radiosurgery. Retrospectively reviewed here are 30 tumours treated in 14 patients with a mean +/- SD follow-up of 34 +/- 24 months. During this time, three of the 14 patients (21%) died, two of generalized progressive disease. Before radiosurgery, the median time between interventions for cranial haemangioblastomas was 3 years (mean 3.9 +/- 5.0 years). After radiosurgery, the tendency for cranial disease progression was similar, 50% of patients developing further disease by 5 years. Local tumour control was achieved in the majority of cases and estimates of this are included. Radiosurgery is a useful palliative measure controlling the majority of haemangioblastomas, although its efficacy in these patients is limited by the tendency of further disease to develop or progress intracranially.

  17. Determination of output factors for stereotactic radiosurgery beams

    Energy Technology Data Exchange (ETDEWEB)

    Fan, J.; Paskalev, K.; Wang, L.; Jin, L.; Li, J.; Eldeeb, A.; Ma, C. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)

    2009-11-15

    Accurate dosimetry of the narrow beam tends to be difficult to perform due to the absence of lateral electronic equilibrium and the steep dose gradient, as well as the finite size of detectors. Thus, although the high dose rate 6 MV beam on the VARIAN Trilogy accelerator is increasingly utilized for stereotactic radiosurgery (SRS) treatment, there is no general agreement in the SRS beam output factor values among the Trilogy user community. Trilogy SRS beams are confined by cone collimators and the available collimator sizes range from 5 and 10 to 30 mm, in every 2 mm increment. A range of the relative output factors are in clinic use. This variation may impair observations of dose response and optimizations of the prescribed dose. It is necessary to investigate an accurate, easily performable, and detector independent method for the narrow beam output factor measurement. In this study, a scanning beam/scanning chamber method was proposed to overcome the limitation/difficulty of using a relatively large detector in narrow beam output factor measurement. Specifically, for the scanning beam method, multiple narrow beams are used for the dose measurement using a finite size chamber. These multiple scanning beams form an equivalent large uniform field which provides lateral electron equilibrium condition. After the measurement, the contributions from neighboring beams are deconvolved and the value is used for output factor determinations. For a Linac that cannot move a beam laterally, the scanning chamber method can be used to achieve the same result. The output factors determined in such a method were compared to chambers (a 0.015 cc PTW PinPoint ion chamber and a 0.125 cc PTW ion chamber) and film measurement, as well as with Monte Carlo simulation. Film and Monte Carlo results are found to be in excellent agreement with the measurement using the scan beam method. However, the VARIAN recommended output factors measured directly by Wellhoefer CC01 chamber and

  18. CT perfusion imaging as an early biomarker of differential response to stereotactic radiosurgery in C6 rat gliomas.

    Directory of Open Access Journals (Sweden)

    Timothy Pok Chi Yeung

    Full Text Available 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.

  19. Hypofractionated stereotactic radiotherapy of acoustic neuroma. Volume changes and hearing results after 89-month median follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Kranzinger, Manfred; Fastner, Gerd [Paracelsus Medical University Clinics (PMU), University Clinic of Radiotherapy and Radio-Oncology, Salzburg County Hospital, Salzburg (Austria); Zehentmayr, Franz; Sedlmayer, Felix [Paracelsus Medical University Clinics (PMU), University Clinic of Radiotherapy and Radio-Oncology, Salzburg County Hospital, Salzburg (Austria); Salzburg County Hospital, Paracelsus Medical University Clinics, radART - Institute for Research and Development on Advanced Radiation Technologies, Salzburg (Austria); Oberascher, Gerhard [Paracelsus Medical University Clinics (PMU), University Clinic of Ear, Nose and Throat Diseases, Salzburg County Hospital, Salzburg (Austria); Merz, Florian; Rahim, Hassan [Salzburg County Hospital, Paracelsus Medical University Clinics, Medical Radiation Protection Unit, Salzburg (Austria); Nairz, Olaf [Clinic Bad Trissl, Oberaudorf (Germany)

    2014-09-15

    The goal of this work was to evaluate toxicity and local control following hypofractionated stereotactic radiation treatment with special focus on changes in tumor volume and hearing capacity. In all, 29 patients with unilateral acoustic neuroma were treated between 2001 and 2007 within a prospective radiation protocol (7 x 4 Gy ICRU dose). Median tumor volume was 0.9 ml. Follow-up started at 6 months and was repeated annually with MRI volumetry and audiometry. Hearing preservation was defined as preservation of Class A/B hearing according to the guidelines of the American Academy of Otolaryngology (1995). No patient had any intervention after a median imaging follow-up of 89.5 months, one patient showed radiological progression. Transient increase of tumor volume developed in 17/29 patients, whereas 22/29 patients (75.9 %) presented with a volume reduction at last follow-up. A total of 21 patients were eligible for hearing evaluation. Mean pure tone average (PTA) deteriorated from 39.3 to 65.9 dB and mean speech discrimination score (SDS) dropped from 74.3 to 38.1 %. The 5-year actuarial Class A/B hearing preservation rate was 50.0 ± 14.4 %. Radiation increases only minimally, if at all, the hearing deterioration which emerges by observation alone. Presbyacusis is not responsible for this deterioration. Transient tumor enlargement is common. Today radiation of small- and medium-sized acoustic neuroma can be performed with different highly conformal techniques as fractionated treatment or single low-dose radiosurgery with equal results regarding tumor control, hearing preservation, and side effects. Hypofractionation is more comfortable for the patient than conventional regimens and represents a serious alternative to frameless radiosurgery. (orig.) [German] Ziel der Studie war die Evaluierung der Toxizitaet und der lokalen Tumorkontrolle einer hypofraktionierten stereotaktischen Bestrahlung mit besonderem Augenmerk auf Veraenderungen von Tumorvolumen und

  20. Current concepts in stereotactic radiosurgery - a neurosurgical and radiooncological point of view

    Directory of Open Access Journals (Sweden)

    Vesper J

    2009-03-01

    Full Text Available Abstract Stereotactic radiosurgery is related to the history of "radiotherapy" and "stereotactic neurosurgery". The concepts for neurosurgeons and radiooncologists have been changed during the last decade and have also transformed neurosurgery. The gamma knife and the stereotactically modified linear accelerator (LINAC are radiosurgical equipments to treat predetermined intracranial targets through the intact skull without damaging the surrounding normal brain tissue. These technical developments allow a more precise intracranial lesion control and offer even more conformal dose plans for irregularly shaped lesions. Histological determination by stereotactic biopsy remains the basis for any otherwise undefined intracranial lesion. As a minimal approach, it allows functional preservation, low risk and high sensitivity. Long-term results have been published for various indications. The impact of radiosurgery is presented for the management of gliomas, metastases, brain stem lesions, benign tumours and vascular malformations and selected functional disorders such as trigeminal neuralgia. In AVM's it can be performed as part of a multimodality strategy including resection or endovascular embolisation. Finally, the technological advances in radiation oncology as well as stereotactic neurosurgery have led to significant improvements in radiosurgical treatment opportunities. Novel indications are currently under investigation. The combination of both, the neurosurgical and the radiooncological expertise, will help to minimize the risk for the patient while achieving a greater treatment success.

  1. Automatic metastatic brain tumor segmentation for stereotactic radiosurgery applications

    Science.gov (United States)

    Liu, Yan; Stojadinovic, Strahinja; Hrycushko, Brian; Wardak, Zabi; Lu, Weiguo; Yan, Yulong; Jiang, Steve B.; Timmerman, Robert; Abdulrahman, Ramzi; Nedzi, Lucien; Gu, Xuejun

    2016-12-01

    The objective of this study is to develop an automatic segmentation strategy for efficient and accurate metastatic brain tumor delineation on contrast-enhanced T1-weighted (T1c) magnetic resonance images (MRI) for stereotactic radiosurgery (SRS) applications. The proposed four-step automatic brain metastases segmentation strategy is comprised of pre-processing, initial contouring, contour evolution, and contour triage. First, T1c brain images are preprocessed to remove the skull. Second, an initial tumor contour is created using a multi-scaled adaptive threshold-based bounding box and a super-voxel clustering technique. Third, the initial contours are evolved to the tumor boundary using a regional active contour technique. Fourth, all detected false-positive contours are removed with geometric characterization. The segmentation process was validated on a realistic virtual phantom containing Gaussian or Rician noise. For each type of noise distribution, five different noise levels were tested. Twenty-one cases from the multimodal brain tumor image segmentation (BRATS) challenge dataset and fifteen clinical metastases cases were also included in validation. Segmentation performance was quantified by the Dice coefficient (DC), normalized mutual information (NMI), structural similarity (SSIM), Hausdorff distance (HD), mean value of surface-to-surface distance (MSSD) and standard deviation of surface-to-surface distance (SDSSD). In the numerical phantom study, the evaluation yielded a DC of 0.98  ±  0.01, an NMI of 0.97  ±  0.01, an SSIM of 0.999  ±  0.001, an HD of 2.2  ±  0.8 mm, an MSSD of 0.1  ±  0.1 mm, and an SDSSD of 0.3  ±  0.1 mm. The validation on the BRATS data resulted in a DC of 0.89  ±  0.08, which outperform the BRATS challenge algorithms. Evaluation on clinical datasets gave a DC of 0.86  ±  0.09, an NMI of 0.80  ±  0.11, an SSIM of 0.999  ±  0.001, an HD of 8

  2. Clinical-radiological evaluation of sequelae of stereotactic radiosurgery for intracranial arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Levy, R.P.; Fabrikant, J.I.; Frankel, K.A.; Phillips, M.H.; Steinberg, G.K.; Marks, M.P.; DeLaPaz, R.L.; Chuang, F.Y.S.

    1989-12-01

    Stereotactic heavy-charged-particle Bragg peak radiosurgery has been used to treat 322 patients with surgically-inaccessible intracranial vascular malformations. (The clinical results of this method for the treatment of angiographically demonstrable arteriovenous malformations (AVMs) and angiographically occult vascular malformations (AOVMs) of the brain are described in separate reports of this symposium). The great majority of patients have had an uneventful post-treatment course with satisfactory health outcomes. However, several categories of delayed sequelae of stereotactic radiosurgery have been identified, involving the vascular structures essential for the integrity of the brain tissue and the brain parenchyma directly. These categories reflect both reaction to injury and to alterations in regional hemodynamic status, and include vasogenic edema, occlusion of functional vasculature, radiation necrosis, and local or remote effects on cerebral arterial aneurysms. 10 refs., 7 figs., 1 tab.

  3. Stereotactic radiosurgery using the Leksell Gamma Knife: current trends and future directives.

    Science.gov (United States)

    Jawahar, Ajay; Jawahar, Lisa L; Nanda, Anil; Sharp, Christopher D; Warren, April; Elrod, John W; Jennings, Merilyn; Alexander, J Steven; Minagar, Alireza

    2004-01-01

    Stereotactic radiosurgery is the extremely precise administration of a radiation dosage in three-dimensional space to treat an increasingly broad spectrum of intracranial and skull-base lesions. 455 patients with various indications were treated using the 201 Source Co-60 Leksell Model "B" Gamma Knife(r) at Louisiana State University Health Sciences Center in Shreveport, Louisiana. 273 (60.2%) patients received radiosurgery as the first line of treatment for their disease. The mean Karnofsky Performance Score (KPS) of the patients was 70. Cerebral metastases were the main indications for radiosurgery at our center accounting for 27% of the patients, while meningioma, AVM, trigeminal neuralgia, movement disorders, and primary CNS malignant tumors were the other indications. Our institutional experience and results indicate that low incidence of complications coupled with a high tumor control rate makes Gamma Knife stereotactic radiosurgery a viable option for patients who must undergo neurosurgery. As the Gamma Knife continues to prove itself as a first-line treatment of many complex brain disorders, new indications for this technology will continue to emerge, further broadening the scope of patient care.

  4. Early experiences of planning stereotactic radiosurgery using 3D printed models of eyes with uveal melanomas

    Directory of Open Access Journals (Sweden)

    Furdová A

    2017-01-01

    Full Text Available Alena Furdová,1 Miron Sramka,2 Andrej Thurzo,3 Adriana Furdová3 1Department of Ophthalmology, Faculty of Medicine, Comenius University, 2Department of Stereotactic Radiosurgery, St Elisabeth Cancer Inst and St Elisabeth University College of Health and Social Work, 3Department of Simulation and Virtual Medical Education, Faculty of Medicine, Comenius University, Bratislava, Slovak Republic Objective: The objective of this study was to determine the use of 3D printed model of an eye with intraocular tumor for linear accelerator-based stereotactic radiosurgery.Methods: The software for segmentation (3D Slicer created virtual 3D model of eye globe with tumorous mass based on tissue density from computed tomography and magnetic resonance imaging data. A virtual model was then processed in the slicing software (Simplify3D® and printed on 3D printer using fused deposition modeling technology. The material that was used for printing was polylactic acid.Results: In 2015, stereotactic planning scheme was optimized with the help of 3D printed model of the patient’s eye with intraocular tumor. In the period 2001–2015, a group of 150 patients with uveal melanoma (139 choroidal melanoma and 11 ciliary body melanoma were treated. The median tumor volume was 0.5 cm3 (0.2–1.6 cm3. The radiation dose was 35.0 Gy by 99% of dose volume histogram.Conclusion: The 3D printed model of eye with tumor was helpful in planning the process to achieve the optimal scheme for irradiation which requires high accuracy of defining the targeted tumor mass and critical structures. Keywords: 3D printing, uveal melanoma, stereotactic radiosurgery, linear accelerator, intraocular tumor, stereotactic planning scheme

  5. Stereotactic laser induced thermotherapy (LITT): a novel treatment for brain lesions regrowing after radiosurgery.

    Science.gov (United States)

    Torres-Reveron, Juan; Tomasiewicz, Hilarie C; Shetty, Anil; Amankulor, Nduka M; Chiang, Veronica L

    2013-07-01

    Since the inception of radiosurgery, the management of brain metastases has become a common problem for neurosurgeons. Although the use of stereotactic radiosurgery and/or whole brain radiation therapy serves to control the majority of disease burden, patients who survive longer than 6-8 months sometimes face the problem of symptomatic radiographically regrowing lesions with few treatment options. Here we investigate the feasibility of use of MRI-guided stereotactic laser induced thermotherapy (LITT) as a novel treatment option for these lesions. Six patients who had previously undergone gamma knife stereotactic radiosurgery for brain metastases were selected. All patients had an initial favorable response to radiosurgery but subsequently developed regrowth of at least one lesion associated with recurrent edema and progressive neurological symptoms requiring ongoing steroids for symptom control. All lesions were evaluated for craniotomy, but were deemed unresectable due to deep location or patient's comorbidities. Stereotactic biopsies were performed prior to the thermotherapy procedure in all cases. LITT was performed using the Visualase system and follow-up MRI imaging was used to determine treatment response. In all six patients biopsy results were negative for tumor and consistent with adverse radiation effects also known as radiation necrosis. Patients tolerated the procedure well and were discharged from the hospital within 48 h of the procedure. In 4/6 cases there was durable improvement of neurological symptoms until death. In all cases steroids were weaned off within 2 months. One patient died from systemic causes related to his cancer a month after the procedure. One patient had regrowth of the lesion 3 months after the procedure and required re-initiation of steroids and standard craniotomy for surgical resection. There were no complications directly related to the thermocoagulation procedure. Stereotactic laser induced thermotherapy is a feasible

  6. Fractionated stereotactic radiosurgery using the Novalis system for the management of pituitary adenomas close to the optic apparatus.

    Science.gov (United States)

    Liao, Huang-I; Wang, Chun-Chieh; Wei, Kuo-Cheng; Chang, Cheng-Nen; Hsu, Yung-Hsin; Lee, Shih-Tseng; Huang, Yin-Cheng; Chen, Hsien-Chih; Hsu, Peng-Wei

    2014-01-01

    Radiosurgery has been proven to be an effective treatment for residual or recurrent pituitary adenomas after surgery. However, it causes severe complications when the optic apparatus is irradiated over the tolerance dose. In this study, we analyzed the feasibility of fractionated stereotactic radiosurgery to treat pituitary tumors close to the optic apparatus. Thirty-four patients from June 2006 to June 2011 with recurrent or residual pituitary adenomas close to (<3 mm) the optic apparatus were treated with fractionated stereotactic radiosurgery. Three fractions with a total dose of 2100 cGy were applied to the tumors. Imaging, examination of vision, and estimation of hormone level were regularly performed before and after radiosurgery. The mean tumor volume before fractioned stereotactic radiosurgery was 5.06±3.08 cm3 (range: 0.82-12.69 cm3). After a mean follow up of 36.8±15.7 months (range: 16-72 months), tumor size was reduced in seven (20.6%) patients and remained the same in the other 27 (79.4%) patients. Vision was improved in one patient and remained stable in the rest. Only one patient developed transient post-treatment diplopia. This study suggests that fractionated stereotactic radiosurgery is safe for treating pituitary adenomas close to the optic apparatus. Studies with more patients and longer follow-up are required to draw definite conclusions.

  7. Noninvasive stereotactic radiosurgery (CyberHeart) for creation of ablation lesions in the atrium.

    Science.gov (United States)

    Sharma, Arjun; Wong, Douglas; Weidlich, Georg; Fogarty, Thomas; Jack, Alice; Sumanaweera, Thilaka; Maguire, Patrick

    2010-06-01

    A variety of catheter-based energy modalities are used for cardiac ablation to treat arrhythmias. Robotic radiosurgery is increasingly being utilized to successfully accomplish precise tissue ablation in anatomically remote areas. The purpose of this study was to examine the experimental feasibility of a noninvasive method using stereotactic robotic radiosurgery (SRS) to create cardiac lesions. Sixteen (16) Hanford-Sinclair mini swine (weight 40-70 kg) under general anesthesia were studied. Baseline computed tomographic scans were performed, followed by electroanatomic mapping using the CARTO system. Stereotactic robotic radiosurgery was performed using the CyberHeart system, with predetermined targets at the cavotricuspid isthmus, AV node, pulmonary vein-left atrial junction, or left atrial appendage. From 25 to 196 days after treatment, the animals were investigated with repeat electroanatomic voltage mapping and transesophageal echocardiography, when possible. The animals then were sacrificed and pathology specimens taken. Dose ranging suggested that 25 Gy was needed to produce an electrophysiologic effect. The time course showed an electrophysiologic effect consistently by 90 days. The method was feasible for producing bidirectional cavotricuspid isthmus block and AV nodal conduction block. The pulmonary vein-left atrial junction and left atrial appendage showed marked voltage reduction to less than 0.05 mV. No spontaneous arrhythmias were observed. Pathology specimens showed no evidence of radiation damage outside the target. Histology samples from target sites showed effects consistent with X-beam radiation. Stereotactic robotic radiosurgery can produce cavotricuspid isthmus block, AV nodal block, and significant decreased voltage at the pulmonary vein-left atrial junction. No other organ damage was seen. The study findings demonstrate the feasibility of this noninvasive treatment method for creating cardiac lesions. This approach merits further investigation

  8. 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.

    Directory of Open Access Journals (Sweden)

    Scott eFloyd

    2012-10-01

    Full Text Available 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 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 radiotherapy course, radiosurgery boost and

  9. Outcomes of Diffusion Tensor Tractography-Integrated Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Tomoyuki, E-mail: kouga-tky@umin.ac.jp [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan); Maruyama, Keisuke; Kamada, Kyousuke; Ota, Takahiro; Shin, Masahiro [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan); Itoh, Daisuke [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Kunii, Naoto [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan); Ino, Kenji; Terahara, Atsuro; Aoki, Shigeki; Masutani, Yoshitaka [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Saito, Nobuhito [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan)

    2012-02-01

    Purpose: To analyze the effect of use of tractography of the critical brain white matter fibers created from diffusion tensor magnetic resonance imaging on reduction of morbidity associated with radiosurgery. Methods and Materials: Tractography of the pyramidal tract has been integrated since February 2004 if lesions are adjacent to it, the optic radiation since May 2006, and the arcuate fasciculus since October 2007. By visually confirming the precise location of these fibers, the dose to these fiber tracts was optimized. One hundred forty-four consecutive patients with cerebral arteriovenous malformations who underwent radiosurgery with this technique between February 2004 and December 2009 were analyzed. Results: Tractography was prospectively integrated in 71 of 155 treatments for 144 patients. The pyramidal tract was visualized in 45, the optic radiation in 22, and the arcuate fasciculus in 13 (two tracts in 9). During the follow-up period of 3 to 72 months (median, 23 months) after the procedure, 1 patient showed permanent worsening of pre-existing dysesthesia, and another patient exhibited mild transient hemiparesis 12 months later but fully recovered after oral administration of corticosteroid agents. Two patients had transient speech disturbance before starting integration of the arcuate fasciculus tractography, but no patient thereafter. Conclusion: Integrating tractography helped prevent morbidity of radiosurgery in patients with brain arteriovenous malformations.

  10. WE-A-304-00: Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    The high fractional doses, stringent requirements for accuracy and precision, and surgical perspective characteristic of intracranial radiosurgery create considerations for treatment planning which are distinct from most other radiotherapy procedures. This session will introduce treatment planning techniques specific to two popular intracranial SRS modalities: Gamma Knife and MLC-based Linac. The basic treatment delivery characteristics of each device will be reviewed with a focus on how those characteristics determine the paradigm used for treatment planning. Basic techniques for treatment planning will be discussed, including considerations such as isodose selection, target and organ-at-risk definition, quality indices, and protection of critical structures. Future directions for SRS treatment planning will also be discussed. Learning Objectives: Introduce the basic physical principles of intracranial radiosurgery and how they are realized in the treatment planning paradigms for Gamma Knife and Linac radiosurgery. Demonstrate basic treatment planning techniques. Discuss metrics for evaluating SRS treatment plan quality. Discuss recent and future advances in SRS treatment planning. D. Schlesinger receives research support from Elekta, AB.

  11. Outcomes of stereotactic radiosurgery for foramen magnum meningiomas: an international multicenter study.

    Science.gov (United States)

    Mehta, Gautam U; Zenonos, Georgios; Patibandla, Mohana Rao; Lin, Chung Jung; Wolf, Amparo; Grills, Inga; Mathieu, David; McShane, Brendan; Lee, John Y; Blas, Kevin; Kondziolka, Douglas; Lee, Cheng-Chia; Lunsford, L Dade; Sheehan, Jason P

    2017-09-01

    OBJECTIVE Meningiomas are the most common benign extramedullary lesions of the foramen magnum; however, their optimal management remains undefined. Given their location, foramen magnum meningiomas (FMMs) can cause significant morbidity, and complete microsurgical removal can be challenging. Anterior and anterolateral FMMs carry greater risks with surgery, but they comprise the majority of these lesions. As an alternative to resection, stereotactic radiosurgery (SRS) has been used to treat FMMs in small case series. To more clearly define the outcomes of SRS and to delineate a rational management paradigm for these lesions, the authors analyzed the safety and efficacy of SRS for FMM in an international multicenter trial. METHODS Seven medical centers participating in the International Gamma Knife Research Foundation (IGKRF) provided data for this retrospective cohort study. Patients who were treated with Gamma Knife radiosurgery and whose clinical and radiological follow-up was longer than 6 months were eligible for study inclusion. Data from pre- and post-SRS radiological and clinical evaluations were analyzed. Stereotactic radiosurgery treatment variables were recorded. RESULTS Fifty-seven patients (39 females and 18 males, with a median age of 64 years) met the study inclusion criteria. Thirty-two percent had undergone prior microsurgical resection. Patients most frequently presented with cranial neuropathy (39%), headache (35%), numbness (32%), and ataxia (30%). Median pre-SRS tumor volume was 2.9 cm(3). Median SRS margin dose was 12.5 Gy (range 10-16 Gy). At the last follow-up after SRS, 49% of tumors were stable, 44% had regressed, and 7% had progressed. Progression-free survival rates at 5 and 10 years were each 92%. A greater margin dose was associated with a significantly increased likelihood of tumor regression, with 53% of tumors treated with > 12 Gy regressing. Fifty-two percent of symptomatic patients noted some clinical improvement. Adverse radiation

  12. Dosimetric characterization of hypofractionated Gamma Knife radiosurgery of large or complex brain tumors versus linear accelerator-based treatments.

    Science.gov (United States)

    Dong, Peng; Pérez-Andújar, Angélica; Pinnaduwage, Dilini; Braunstein, Steve; Theodosopoulos, Philip; McDermott, Michael; Sneed, Penny; Ma, Lijun

    2016-12-01

    OBJECTIVE Noninvasive Gamma Knife (GK) platforms, such as the relocatable frame and on-board imaging, have enabled hypofractionated GK radiosurgery of large or complex brain lesions. This study aimed to characterize the dosimetric quality of such treatments against linear accelerator-based delivery systems that include the CyberKnife (CK) and volumetric modulated arc therapy (VMAT). METHODS Ten patients treated with VMAT at the authors' institution for large brain tumors (> 3 cm in maximum diameter) were selected for the study. The median prescription dose was 25 Gy (range 20-30 Gy) in 5 fractions. The median planning target volume (PTV) was 9.57 cm(3) (range 1.94-24.81 cm(3)). Treatment planning was performed using Eclipse External Beam Planning V11 for VMAT on the Varian TrueBeam system, Multiplan V4.5 for the CyberKnife VSI System, and Leksell GammaPlan V10.2 for the Gamma Knife Perfexion system. The percentage of the PTV receiving at least the prescription dose was normalized to be identical across all platforms for individual cases. The prescription isodose value for the PTV, conformity index, Paddick gradient index, mean and maximum doses for organs at risk, and normal brain dose at variable isodose volumes ranging from the 5-Gy isodose volume (V5) to the 15-Gy isodose volume (V15) were compared for all of the cases. RESULTS The mean Paddick gradient index was 2.6 ± 0.2, 3.2 ± 0.5, and 4.3 ± 1.0 for GK, CK, and VMAT, respectively (p 0.06). The average prescription isodose values were 52% (range 47%-69%), 60% (range 46%-68%), and 88% (range 70%-94%) for GK, CK, and VMAT, respectively, thus producing significant variations in dose hot spots among the 3 platforms. Furthermore, the mean V5 values for GK and CK were similar (p > 0.79) at 71.9 ± 36.2 cm(3) and 73.3 ± 31.8 cm(3), respectively, both of which were statistically lower (p < 0.01) than the mean V5 value of 124.6 ± 67.1 cm(3) for VMAT. CONCLUSIONS Significantly better near-target normal brain

  13. Hypofractionated stereotactic radiotherapy for brain metastases from lung cancer. Evaluation of indications and predictors of local control

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, Takeaki [Kobe University Graduate School of Medicine, Division of Radiation Oncology, Hyogo (Japan); Seirei Mikatahara General Hospital, Department of Radiation Oncology, Shizuoka (Japan); Yamada, Kazunari; Isogai, Kenta; Tonosaki, Yoshihiro [Seirei Mikatahara General Hospital, Department of Radiation Oncology, Shizuoka (Japan); Harada, Aya [Kobe Minimum Invasive Cancer Medical Center, Department of Radiation Oncology, Hyogo (Japan); Demizu, Yusuke [Hyogo Ion Beam Medical Center, Department of Radiology, Hyogo (Japan); Miyawaki, Daisuke; Yoshida, Kenji; Ejima, Yasuo; Sasaki, Ryohei [Kobe University Graduate School of Medicine, Division of Radiation Oncology, Hyogo (Japan)

    2016-06-15

    To evaluate the efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) for brain metastases (BMs) from lung cancer, and to explore prognostic factors associated with local control (LC) and indication. We evaluated patients who were treated with linac-based HSRT for BMs from lung cancer. Lesions treated with stereotactic radiosurgery (SRS) in the same patients during the same periods were analysed and compared with HSRT in terms of LC or toxicity. There were 53 patients with 214 lesions selected for this analysis (HSRT: 76 lesions, SRS: 138 lesions). For HSRT, the median prescribed dose was 35 Gy in 5 fractions. The 1-year LC rate was 83.6 % in HSRT; on multivariate analysis, a planning target volume (PTV) of <4 cm{sup 3}, biologically effective dose (BED{sub 10}) of ≥51 Gy, and adenocarcinoma were significantly associated with better LC. Moreover, in PTVs ≥ 4 cm{sup 3}, there was a significant difference in LC between BED{sub 10} < 51 Gy and ≥ 51 Gy (p = 0.024). On the other hand, in PTVs < 4 cm{sup 3}, both HSRT and SRS had good LC with no significant difference (p = 0.195). Radiation necrosis emerged in 5 of 76 lesions (6.6 %) treated with HSRT and 21 of 138 (15.2 %) lesions treated with SRS (p = 0.064). Linac-based HSRT was safe and effective for BMs from lung cancer, and hence might be particularly useful in or near an eloquent area. PTV, BED{sub 10}, and pathological type were significant prognostic factors. Furthermore, in BMs ≥ 4 cm{sup 3}, a dose of BED ≥ 51 Gy should be considered. (orig.) [German] Beurteilung von Wirksamkeit und Toxizitaet einer hypofraktionierten stereotaktischen Strahlentherapie (HSRT) zur Behandlung von Hirnmetastasen (HM) eines Lungenkarzinoms und Erforschung von mit der lokalen Kontrolle (LK) und der Indikation assoziierten Prognosefaktoren. Analysiert wurden Daten von Patienten (n = 53), die sich einer Linearbeschleuniger-basierten HSRT unterzogen (mit HSRT behandelte Laesionen n = 76; Median der

  14. Repeat stereotactic radiosurgery in the management of brain metastases from NSCLC: A case report and review of the literature

    OpenAIRE

    2013-01-01

    The aims of radiotherapeutic treatment of brain metastases include maintaining neurocognitive function and improvement of survival. Based on these premises, we present a case report in which the role of repeat stereotactic radiosurgery (SRS) was investigated in a patient with a recurrent brain metastasis from non-small cell lung cancer in the same area as previously treated with radiosurgery. A 40-year-old male caucasian patient was diagnosed with brain metastasis from non-small cell lung can...

  15. Dosimetric performance and array assessment of plastic scintillation detectors for stereotactic radiosurgery quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Gagnon, Jean-Christophe; Theriault, Dany; Guillot, Mathieu; Archambault, Louis; Beddar, Sam; Gingras, Luc; Beaulieu, Luc [Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec G1R 2J6 (Canada); Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec G1R 2J6 (Canada); Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec G1R 2J6 (Canada); Department of Radiation Physics, Unit 94, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec G1R 2J6 (Canada)

    2012-01-15

    Purpose: To compare the performance of plastic scintillation detectors (PSD) for quality assurance (QA) in stereotactic radiosurgery conditions to a microion-chamber (IC), Gafchromic EBT2 films, 60 008 shielded photon diode (SD) and unshielded diodes (UD), and assess a new 2D crosshair array prototype adapted to small field dosimetry. Methods: The PSD consists of a 1 mm diameter by 1 mm long scintillating fiber (BCF-60, Saint-Gobain, Inc.) coupled to a polymethyl-methacrylate optical fiber (Eska premier, Mitsubishi Rayon Co., Ltd., Tokyo, Japan). Output factors (S{sub c,p}) for apertures used in radiosurgery ranging from 4 to 40 mm in diameter have been measured. The PSD crosshair array (PSDCA) is a water equivalent device made up of 49 PSDs contained in a 1.63 cm radius area. Dose profiles measurements were taken for radiosurgery fields using the PSDCA and were compared to other dosimeters. Moreover, a typical stereotactic radiosurgery treatment using four noncoplanar arcs was delivered on a spherical phantom in which UD, IC, or PSD was placed. Using the Xknife planning system (Integra Radionics Burlington, MA), 15 Gy was prescribed at the isocenter, where each detector was positioned. Results: Output Factors measured by the PSD have a mean difference of 1.3% with Gafchromic EBT2 when normalized to a 10 x 10 cm{sup 2} field, and 1.0% when compared with UD measurements normalized to the 35 mm diameter cone. Dose profiles taken with the PSD crosshair array agreed with other single detectors dose profiles in spite of the presence of the 49 PSDs. Gamma values comparing 1D dose profiles obtained with PSD crosshair array with Gafchromic EBT2 and UD measured profiles shows 98.3% and 100.0%, respectively, of detector passing the gamma acceptance criteria of 0.3 mm and 2%. The dose measured by the PSD for a complete stereotactic radiosurgery treatment is comparable to the planned dose corrected for its SD-based S{sub c,p} within 1.4% and 0.7% for 5 and 35 mm diameter cone

  16. ASSOCIATION BETWEEN COMPUTED TOMOGRAPHIC CHARACTERISTICS AND FRACTURES FOLLOWING STEREOTACTIC RADIOSURGERY IN DOGS WITH APPENDICULAR OSTEOSARCOMA.

    Science.gov (United States)

    Kubicek, Lyndsay; Vanderhart, Daniel; Wirth, Kimberly; An, Qi; Chang, Myron; Farese, James; Bova, Francis; Sudhyadhom, Atchar; Kow, Kelvin; Bacon, Nicholas J; Milner, Rowan

    2016-05-01

    The objective of this observational, descriptive, retrospective study was to report CT characteristics associated with fractures following stereotactic radiosurgery in canine patients with appendicular osteosarcoma. Medical records (1999 and 2012) of dogs that had a diagnosis of appendicular osteosarcoma and undergone stereotactic radiosurgery were reviewed. Dogs were included in the study if they had undergone stereotactic radiosurgery for an aggressive bone lesion with follow-up information regarding fracture status, toxicity, and date and cause of death. Computed tomography details, staging, chemotherapy, toxicity, fracture status and survival data were recorded. Overall median survival time (MST) and fracture rates of treated dogs were calculated. CT characteristics were evaluated for association with time to fracture. Forty-six dogs met inclusion criteria. The median overall survival time was 9.7 months (95% CI: 6.9-14.3 months). The fracture-free rates at 3, 6, and 9 months were 73%, 44%, and 38% (95% CI: 60-86%, 29-60%, and 22-54%), respectively. The region of bone affected was significantly associated with time to fracture. The median time to fracture was 4.2 months in dogs with subchondral bone involvement and 16.3 months in dogs without subchondral bone involvement (P-value = 0.027, log-rank test). Acute and late skin effects were present in 58% and 16% of patients, respectively. Findings demonstrated a need for improved patient selection for this procedure, which can be aided by CT-based prognostic factors to predict the likelihood of fracture. © 2016 American College of Veterinary Radiology.

  17. Intracranial Metastatic Neuroblastoma Treated with Gamma Knife Stereotactic Radiosurgery: Report of Two Novel Cases

    Directory of Open Access Journals (Sweden)

    Nathan C. Rowland

    2012-01-01

    Full Text Available Intracranial metastasis of neuroblastoma (IMN is associated with poor survival. No curative therapy for the treatment of IMN currently exists. Unfractionated radiotherapy may be beneficial in the treatment of IMN given the known radiosensitivity of neuroblastoma as well as its proclivity to metastasize as discrete lesions. We present two patients with IMN treated with Gamma Knife stereotactic radiosurgery (SRS. Single-fraction radiotherapy yielded temporary reduction of tumor burden and stability of disease in both patients. SRS may be a useful palliative tool in the treatment of IMN and expands the overall treatment options for this disease.

  18. The treatment planning of segmental, conformal stereotactic radiosurgery utilizing a standard multileaf collimator.

    Science.gov (United States)

    Archer, P G; Balter, J M; Ross, D A; Hayman, J A; Sandler, H M

    1999-01-01

    Over a period of approximately 3 years, our institution has implemented and refined a system of Stereotactic Radiosurgery (SRS) which utilizes the standard multi leaf collimator (MLC) of the Scanditronix MM50 Racetrack Microtron and treats in an arrangement of segmental "pseudo-arcs." This system employs a commercial BRW based stereotactic frame which is mounted to the treatment table. With the exception of the table-mounted frame hardware there have been no modifications to the treatment machine to accommodate these treatments. By use of standard evaluation parameters (e.g., treatment time, planning time, dose conformance and dose heterogeneity ratios) this system compares quite favorably with reported data from institutions treating SRS with either a GammaKnife or a standard linear accelerator with tertiary collimators.

  19. Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery.

    Science.gov (United States)

    Katsoulakis, Evangelia; Laufer, Ilya; Bilsky, Mark; Agaram, Narasimhan P; Lovelock, Michael; Yamada, Yoshiya

    2017-01-01

    OBJECTIVE Spine radiosurgery is increasingly being used to treat spinal metastases. As patients are living longer because of the increasing efficacy of systemic agents, appropriate follow-up and posttreatment management for these patients is critical. Tumor progression after spine radiosurgery is rare; however, vertebral compression fractures are recognized as a more common posttreatment effect. The use of radiographic imaging alone posttreatment may makeit difficult to distinguish tumor progression from postradiation changes such as fibrosis. This is the largest series from a prospective database in which the authors examine histopathology of samples obtained from patients who underwent surgical intervention for presumed tumor progression or mechanical pain secondary to compression fracture. The majority of patients had tumor ablation and resulting fibrosis rather than tumor progression. The aim of this study was to evaluate tumor histopathology and characteristics of patients who underwent pathological sampling because of radiographic tumor progression, fibrosis, or collapsed vertebrae after receiving high-dose single-fraction stereotactic radiosurgery. METHODS Between January 2005 and January 2014, a total of 582 patients were treated with linear accelerator-based single-fraction (18-24 Gy) stereotactic radiosurgery. The authors retrospectively identified 30 patients (5.1%) who underwent surgical intervention for 32 lesions with vertebral cement augmentation for either mechanical pain or instability secondary to vertebral compression fracture (n = 17) or instrumentation (n = 15) for radiographic tumor progression. Radiation and surgical treatment, histopathology, and long-term outcomes were reviewed. Survival and time to recurrence were calculated using the Kaplan-Meier method. RESULTS The mean age at the time of radiosurgery was 59 years (range 36-80 years). The initial pathological diagnoses were obtained for all patients and primarily included radioresistant

  20. Stereotactic radiosurgery for trigeminal neuralgia utilizing the BrainLAB Novalis system.

    Science.gov (United States)

    Zahra, Hadi; Teh, Bin S; Paulino, Arnold C; Yoshor, Daniel; Trask, Todd; Baskin, David; Butler, E Brian

    2009-12-01

    Stereotactic radiosurgery (SRS) is one of the least invasive treatments for trigeminal neuralgia (TN). To date, most reports have been about Cobalt-based treatments (i.e., Gamma Knife) with limited data on image-guided stereotactic linear accelerator treatments. We describe our initial experience of using BrainLAB Novalis stereotactic system for the radiosurgical treatment of TN. A total of 20 patients were treated between July 2004 and February 2007. Each SRS procedure was performed using the BrainLAB Novalis System. Thin cuts MRI images of 1.5 mm thickness were acquired and fused with the simulation CT of each patient. Majority of the patients received a maximum dose of 90 Gy. The median brainstem dose to 1.0 cc and 0.1 cc was 2.3 Gy and 13.5 Gy, respectively. In addition, specially acquired three-dimensional fast imaging sequence employing steady-state acquisition (FIESTA) MRI was utilized to improve target delineation of the trigeminal proximal nerve root entry zone. Barrow Neurological Index (BNI) pain scale for TN was used for assessing treatment outcome. At a median follow-up time of 14.2 months, 19 patients (95%) reported at least some improvement in pain. Eight (40%) patients were completely pain-free and stopped all medications (BNI Grade I) while another 2 (10%) patients also stopped medications but reported occasional pain (BNI Grade II). Another 2 (10%) patients reported no pain and 7 (35%) patients only occasional pain while continuing medications, BNI Grade IIIA and IIIB, respectively. Median time to pain control was 8.5 days (range: 1-70 days). No patient reported severe pain, worsening pain or any pain not controlled on their previously taken medication. Intermittent or persistent facial numbness following treatments occurred in 35% of patients. No other complications were reported. Stereotactic radiosurgery using the BrainLAB Novalis system is a safe and effective treatment for TN. This information is important as more centers are obtaining image

  1. SU-F-P-05: Initial Experience with an Independent Certification Program for Stereotactic Radiosurgery and Stereotactic Body Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Solberg, T [University of Pennsylvania, Philadelphia, PA (United States); Robar, J [Capital District Health Authority, Halifax, NS (Canada); Gevaert, T [University Hospital Brussels, Brussels (Belgium); Todorovic, M [Universitats-Klinikum Hamburg-Eppendorf, Hamburg (Germany); Howe, J [Associates In Medical Physics, Louisville, KY (United States)

    2016-06-15

    Purpose: The ASTRO document “Safety is no accident: A FRAMEWORK FOR QUALITY RADIATION ONCOLOGY AND CARE” recommends external reviews of specialized modalities. The purpose of this presentation is to describe the implementation of such a program for Stereotactic Radiosurgery (SRS) and Stereotactic Body radiation Therapy (SBRT). Methods: The margin of error for SRS and SBRT delivery is significantly smaller than that of conventional radiotherapy and therefore requires special attention and diligence. The Novalis Certified program was created to fill an unmet need for specialized SRS / SBRT credentialing. A standards document was drafted by a panel of experts from several disciplines, including medical physics, radiation oncology and neurosurgery. The document, based on national and international standards, covers requirements in program structure, personnel, training, clinical application, technology, quality management, and patient and equipment QA. The credentialing process was modeled after existing certification programs and includes an institution-generated self-study, extensive document review and an onsite audit. Reviewers generate a descriptive report, which is reviewed by a multidisciplinary expert panel. Outcomes of the review may include mandatory requirements and optional recommendations. Results: 15 institutions have received Novalis Certification, including 3 in the US, 7 in Europe, 4 in Australia and 1 in Asia. 87 other centers are at various stages of the process. Nine reviews have resulted in mandatory requirements, however all of these were addressed within three months of the audit report. All reviews have produced specific recommendations ranging from programmatic to technical in nature. Institutions felt that the credentialing process addressed a critical need and was highly valuable to the institution. Conclusion: Novalis Certification is a unique peer review program assessing safety and quality in SRS and SBRT, while recognizing

  2. Hypofractionated stereotactic body radiation therapy as monotherapy for intermediate-risk prostate cancer

    Directory of Open Access Journals (Sweden)

    Ju Andrew W

    2013-01-01

    Full Text Available Abstract Background Hypofractionated stereotactic body radiation therapy (SBRT has been advanced as monotherapy for low-risk prostate cancer. We examined the dose distributions and early clinical outcomes using this modality for the treatment of intermediate-risk prostate cancer. Methods Forty-one sequential hormone-naïve intermediate-risk prostate cancer patients received 35–36.25 Gy of CyberKnife-delivered SBRT in 5 fractions. Radiation dose distributions were analyzed for coverage of potential microscopic ECE by measuring the distance from the prostatic capsule to the 33 Gy isodose line. PSA levels, toxicities, and quality of life (QOL measures were assessed at baseline and follow-up. Results All patients completed treatment with a mean coverage by the 33 Gy isodose line extending >5 mm beyond the prostatic capsule in all directions except posteriorly. Clinical responses were documented by a mean PSA decrease from 7.67 ng/mL pretreatment to 0.64 ng/mL at the median follow-up of 21 months. Forty patients remain free from biochemical progression. No Grade 3 or 4 toxicities were observed. Mean EPIC urinary irritation/obstruction and bowel QOL scores exhibited a transient decline post-treatment with a subsequent return to baseline. No significant change in sexual QOL was observed. Conclusions In this intermediate-risk patient population, an adequate radiation dose was delivered to areas of expected microscopic ECE in the majority of patients. Although prospective studies are needed to confirm long-term tumor control and toxicity, the short-term PSA response, biochemical relapse-free survival rate, and QOL in this interim analysis are comparable to results reported for prostate brachytherapy or external beam radiotherapy. Trial registration The Georgetown Institutional Review Board has approved this retrospective study (IRB 2009–510.

  3. Low Incidence of Fatigue after Hypofractionated Stereotactic Body Radiation Therapy (SBRT for Localized Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Chiranjeev eDash

    2012-10-01

    Full Text Available Background: Fatigue is a common side-effect of conventional prostate cancer radiation therapy. The increased delivery precision necessitated by the high dose per fraction of stereotactic body radiation therapy (SBRT offers the potential of reduce target volumes and hence the exposure of normal tissues to high radiation doses. Herein, we examine the level of fatigue associated with SBRT treatment.Methods: Forty patients with localized prostate cancer treated with hypofractionated SBRT, and a minimum of 12 months follow-up were included in this analysis. Self-reported fatigue and other quality of life measures were assessed at baseline and at 1, 3, 6, 9, and 12 months post-SBRT.Results: Mean levels of fatigue were elevated at 1 month post-SBRT compared to baseline values (p=0.02. Fatigue at the 3-month follow-up and later were higher but not statistically significantly different compared to baseline. African-American patients reported higher fatigue post-SBRT than Caucasian patients. Fatigue was correlated with hormonal symptoms as measured by the Expanded Prostate Cancer Index Composite (EPIC quality of life questionnaire, but not with urinary, bowel, or sexual symptoms. Age, co-morbidities, smoking, prostate specific antigen (PSA levels, testosterone levels, and tumor stage were not associated with fatigue. Conclusion: This is the first study to investigate fatigue as a side-effect of SBRT. In contrast to standard radiation therapy, results suggest SBRT-related fatigue is short-term rather than a long-term side effect of SBRT. These results also suggest post-SBRT fatigue to be a more frequent complication in African-Americans than Caucasians.

  4. Quality of coverage: conformity measures for stereotactic radiosurgery.

    Science.gov (United States)

    Wu, Q-R Jackie; Wessels, B W; Einstein, D B; Maciunas, R J; Kim, E Y; Kinsella, T J

    2003-01-01

    In radiosurgery, conformity indices are often used to compare competing plans, evaluate treatment techniques, and assess clinical complications. Several different indices have been reported to measure the conformity of the prescription isodose to the target volume. The PITV recommended in the Radiation Therapy Oncology Group (RTOG) radiosurgery guidelines, defined as the ratio of the prescription isodose volume (PI) over the target volume (TV), is probably the most frequently quoted. However, these currently used conformity indices depend on target size and shape complexity. The objectives of this study are to systematically investigate the influence of target size and shape complexity on existing conformity indices, and to propose a different conformity index-the conformity distance index (CDI). The CDI is defined as the average distance between the target and the prescription isodose line. This study examines five case groups with volumes of 0.3, 1.0, 3.0, 10.0, and 30.0 cm(3). Each case group includes four simulated shapes: a sphere, a moderate ellipsoid, an extreme ellipsoid, and a concave "C" shape. Prescription dose coverages are generated for three simplified clinical scenarios, i.e., the PI completely covers the TV with 1 and 2 mm margins, and the PI over-covers one half of the TV with a 1 mm margin and under-covers the other half with a 1 mm margin. Existing conformity indices and the CDI are calculated for these five case groups as well as seven clinical cases. When these values are compared, the RTOG PITV conformity index and other similar conformity measures have much higher values than the CDI for smaller and more complex shapes. With the same quality of prescription dose coverage, the CDI yields a consistent conformity measure. For the seven clinical cases, we also find that the same PITV values can be associated with very different conformity qualities while the CDI predicts the conformity quality accurately. In summary, the proposed CDI provides

  5. Stereotactic LINAC radiosurgery for the treatment of brainstem cavernomas

    Energy Technology Data Exchange (ETDEWEB)

    Fuetsch, M.; El Majdoub, F.; Hoevels, M.; Sturm, V.; Maarouf, M. [Koeln Univ. (Germany). Dept. of Stereotaxy and Functional Neurosurgery; Mueller, R.P. [Koeln Univ. (Germany). Dept. of Radiation Oncology

    2012-04-15

    Background: The management of deep-seated cerebral cavernous malformations (CCMs) is still controversial. Although surgery remains the treatment of choice in patients with recurrent hemorrhage, patients with CCMs located in the brainstem are in many cases not eligible for resection due to high procedure-related morbidity and mortality. We evaluated the long-term outcome of LINAC radiosurgery (LINAC-RS) for the treatment of brainstem CCMs. Patients and methods: Between December 1992 and March 2008, 14 patients (6 men, 8 women) harboring brainstem CCMs underwent LINAC-RS. Pretreatment neuroimaging showed no associated developmental venous angiomas (DVAs) in any of our patients. Prior to treatment, all patients suffered at least from one symptomatic hemorrhage (median 1.8, range 1-3). A median follow-up of 7.1 years (range 2.0-16.8 years) could be obtained in 12 patients. We applied a median tumor surface dose of 13.9 Gy (range 11-18 Gy; median tumor volume 1.6 ml, range 0.4-4.3 ml). Results: Following LINAC-RS, neurological outcome improved in 4 (33.3%) and remained unchanged in 8 patients (66.7%). Rebleeding with subsequent transient neurological status deterioration occurred in 4 patients (33.3%), leading to additional surgical resection in 2 patients (16.7%). The corresponding annual hemorrhage rate was 4.8% (4/82.8 patient-years). Adverse radiation effects (ARE, defined by perilesional hyperintensity on T{sub 2}-weighted MR images) were revealed in 3 patients (25%), leading to transient neurological deficits in 2 patients (16.7%). There were no procedure-related complications leading to either permanent morbidity or mortality. Conclusion: Our results support the role of LINAC-RS as an efficient and safe treatment to significantly reduce the annual hemorrhage rate in patients suffering from brainstem CCMs not eligible to microsurgery. Compared with radiosurgery for arteriovenous malformations (AVMs), the intervention-related morbidity is higher. (orig.)

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

    Science.gov (United States)

    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.

  7. Stereotactic radiosurgery for the treatment of brain metastases

    Energy Technology Data Exchange (ETDEWEB)

    Hiyama, Hirofumi; Arai, Koji; Izawa, Masahiro; Takakura, Kintomo [Tokyo Women`s Medical Coll. (Japan). Neurological Inst.

    1996-02-01

    The treatment outcome of the metastatic brain tumor in Tokyo Women`s Medical College was reported, and it was described on present state and problem of radiosurgery (RS). One hundred five lesions of 50 patients (male 36, female 12, age 27-85 years) undertaken RS by gamma knife were studied. The primary lesions were the lungs in 23 patients, digestive tract in 12, mammary gland in 4, kidney in 3, thyroid gland in 13, prostate gland in 2 and the other in 3. Thirty nine patients had primary tumor, and 11 patients had recurrent tumor. The volume of 105 lesions was 0.03-56 ml (mean 6.4 ml), and the treatment was carried out for these tumors at average maximum dose 47Gy, average limbic dosage 23Gy. In the image findings, elimination of 46 lesions (44%), reduction of 39 lesions (37%), unchangeable 7 lesions (7%), increase of 13 lesions (13%) were recognized, and tumor reduction rate 81%, local control rate 88% were obtained. The local control rate was around 90% of the tumor, which seize was 15 ml or less. After the treatment, radionecrosis were suspected in 2 lesions of 1 patient. Appearance or aggravation of the edema by the radiation were observed 1-2 month after the treatment in 6 lesions of 5 patients. By the treatment, the following were improved: the hemiplegia in 9 patients, the aphasia in 2, the vertigo in 3. On prognosis, 21 of 46 patients except for the uncertain 4 were alive and 25 died. Through RS is the therapy which is very effective for the metastatic brain tumor, it also exists on some problems to be reached. (A.N.).

  8. CyberKnife Stereotactic Radiosurgery for Recurrent, Metastatic, and Residual Hemangiopericytomas

    Directory of Open Access Journals (Sweden)

    Soltys Scott G

    2011-06-01

    Full Text Available Abstract Objective Hemangiopericytoma is a rare and aggressive meningeal tumor. Although surgical resection is the standard treatment, hemangiopericytomas often recur with high incidences of metastasis. The purpose of this study was to evaluate the role of CyberKnife stereotactic radiosurgery (CK in the management of recurrent, metastatic, and residual hemangiopericytomas. Methods In a review of the Stanford radiosurgery database between 2002 and 2009, the authors found 14 patients who underwent CK therapy for recurrent, metastatic, and residual hemangiopericytomas. A total of 24 tumors were treated and the median patient age was 52 years (range 29-70 years at the time of initial CK therapy. The median follow-up period was 37 months (10-73 months and all patients had been previously treated with surgical resection. Mean tumor volume was 9.16 cm3 and the mean marginal and maximum radiosurgical doses to the tumors were 21.2 Gy and 26.8 Gy, respectively. Results Of the 24 tumors treated, 22 have clinical follow-up data at this time. Of those 22 tumors, 12 decreased in size (54.5%, 6 remained unchanged (27.3%, and 4 showed recurrence (18.2% after CK therapy. Progression-free survival rate was 95%, 71.5%, and 71.5% at 1, 3, and 5 years after multiple CK treatments. The 5-year survival rate after CK was 81%. Conclusions CK is an effective and safe management option for hemangiopericytomas. The current series demonstrates a tumor control of 81.8%. Other institutions have demonstrated similar outcomes with stereotactic radiosurgery, with tumor control ranging from 46.4% to 100%.

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

    Energy Technology Data Exchange (ETDEWEB)

    Dunavoelgyi, Roman [Department of Ophthalmology, Medical University of Vienna, Vienna (Austria); Dieckmann, Karin [Department of Radiology, Medical University of Vienna, Vienna (Austria); Gleiss, Andreas [Section of Clinical Biometrics, Medical University of Vienna, Vienna (Austria); Sacu, Stefan; Kircher, Karl; Georgopoulos, Michael [Department of Ophthalmology, Medical University of Vienna, Vienna (Austria); Georg, Dietmar [Department of Radiology, Medical University of Vienna, Vienna (Austria); Zehetmayer, Martin, E-mail: martin.zehetmayer@meduniwien.ac.at [Department of Ophthalmology, Medical University of Vienna, Vienna (Austria); Poetter, Richard [Department of Radiology, Medical University of Vienna, Vienna (Austria)

    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.

  10. Microinvasive tumor endoresection in combination with ocular stereotactic radiosurgery.

    Science.gov (United States)

    Sinyavskiy, Oleg A; Troyanovsky, Roman L; Ivanov, Pavel I; Golovin, Alexandr S; Tibilov, Andrey V; Solonina, Svetlana N; Astapenko, Anna M; Zubatkina, Irina S

    2016-12-01

    OBJECTIVE The use of Gamma Knife radiosurgery (GKRS) as monotherapy in the treatment of uveal melanoma (UM) allows clinicians to achieve high local tumor control with low recurrence but does not prevent secondary enucleation due to glaucoma in cases of large tumors. The authors analyzed indications for tumor endoresection (ER), the time interval between irradiation and surgery, and the features and results of performing ER for UM after GKRS. METHODS Thirty-seven patients between 28 and 78 years of age (16 male and 11 female patients) with UM underwent GKRS with a dose of 70 to 80 Gy that was applied to the center of the tumor with complete immobilization of the eye during the procedure. Tumor resection with histological investigation was performed in 24 eyes (transscleral resection was performed in 3 eyes, and ER was performed in 21 eyes) at 3 to 97 days after GKRS, mainly during the first 2 or 3 weeks. As a rule, ER (21 eyes) was performed to treat large, centrally localized, or equatorial UMs with exudative macula-on retinal detachment that reduced vision. The average tumor height was 8.9 mm, and the average width was 13.7 mm at the base. ER for UM included phacoemulsification, microinvasive vitrectomy with transretinal tumor resection, laser photocoagulation, and application of a temporary silicone oil tamponade. Seven patients received intraocular injections of inhibitors of angiogenesis for the prevention and treatment of radiation neuroretinopathy. The follow-up period ranged from 8 to 41 months. RESULTS Preservation of the eyes without tumor recurrence was achieved in all 37 patients after GKRS (monotherapy and combined therapy). One patient died of liver metastases at 21 months after GKRS. In the ER group (21 eyes), drug-resistant glaucoma with low visual acuity appeared in 4 eyes (19%) with long-existing total exudative retinal detachment and delayed operations. Severe radiation neuroretinopathy with macular edema occurred in 4 of 21 cases (19

  11. 3D quantitative assessment of response to fractionated stereotactic radiotherapy and single-session stereotactic radiosurgery of vestibular schwannoma

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, T. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, Baltimore, MD (United States); University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Neuroradiology, Hamburg (Germany); Chapiro, J. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Interventional Radiology, Baltimore, MD (United States); Lin, M. [Philips Research North America, Ultrasound Imaging and Interventions (UII), Briarcliff Manor, NY (United States); Geschwind, J.F. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Interventional Radiology, Baltimore, MD (United States); Yale University School of Medicine, Department of Radiology and Imaging Science, New Haven, CT (United States); Kleinberg, L. [The Johns Hopkins University School of Medicine, Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD (United States); Rigamonti, D.; Jusue-Torres, I.; Marciscano, A.E. [The Johns Hopkins University School of Medicine, Department of Neurological Surgery, Baltimore, MD (United States); Yousem, D.M. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, Baltimore, MD (United States)

    2016-03-15

    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. 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, 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. 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 cm{sup 3}, 8-10 years after: 1.77 cm{sup 3}) and ETV despite radiation therapy compared to responders (median TTV pre-treatment: 1.06 cm{sup 3}; 10-12 years after: 0.81 cm{sup 3}; p = 0.001). 3D quantification of VS showed a significant decrease in TTV and ETV on FSRT-treated patients only. NR had significantly greater TTV and ETV over time. (orig.)

  12. Clinical results of stereotactic hellium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Levy, R.P.; Fabrikant, J.I.; Lyman, J.T.; Frankel, K.A.; Phillips, M.H.; Lawrence, J.H.; Tobias, C.A.

    1989-12-01

    The first therapeutic clinical trial using accelerated heavy-charged particles in humans was performed at Lawrence Berkeley Laboratory (LBL) for the treatment of various endocrine and metabolic disorders of the pituitary gland, and as suppressive therapy for adenohypophyseal hormone-responsive carcinomas and diabetic retinopathy. In acromegaly, Cushing's disease, Nelson's syndrome and prolactin-secreting tumors, the therapeutic goal in the 433 patients treated has been to destroy or inhibit the growth of the pituitary tumor and control hormonal hypersecretion, while preserving a functional rim of tissue with normal hormone-secreting capacity, and minimizing neurologic injury. An additional group of 34 patients was treated for nonsecreting chromophobe adenomas. This paper discusses the methods and results of stereotactic helium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory. 11 refs.

  13. Three Dimensional Expansion of Margins for Single-fraction Treatments: Stereotactic Radiosurgery Brain Cases

    CERN Document Server

    Zhang, Qinghui; Song, Yulin; Burman, Chandra

    2012-01-01

    Purpose: To derive a clinical margin formula between clinical target volume (CTV) and planning target volume (PTV) for single-fraction stereotactic radiosurgery (SRS). Methods: In previous publications on the margin between CTV and PTV, a Gaussian function with zero mean sys-tematic error was assumed for systematic errors and the machine systematic error was ignored; in this work we pre-sumed a Dirac delta function for the machine systematic error for a given machine and nonzero mean systematic error was assumed. Mathematical formulas for calculating the CTV-PTV margin for single-fraction SRS cases was proposed. Results: Margins for single fraction treatment were derived such that the CTV receives the prescribed dose in 95% of SRS patients. The margins defined in this study were machine specific and account for nonzero mean systematic error. The differences between our formulas and a previously published formula were discussed. Conclusion: Clinical margin formulas are proposed for determining the margin betwe...

  14. Stereotactic Radiosurgery as Part of Multimodal Treatment in a Bulky Leptomeningeal Recurrence of Breast Cancer.

    Science.gov (United States)

    Bertke, Matthew H; Burton, Eric C; Shaughnessy, Joseph N

    2016-03-08

    Breast cancer metastatic to the brain and/or leptomeningeal spread of disease is a frequently encountered clinical situation, especially given the extended course of disease in these patients. Systemic therapies can often effectively prolong extracranial disease control, making effective strategies to control central nervous system-based disease even more critical. We present a case of bulky leptomeningeal relapse of breast cancer in the setting of prior whole brain radiation therapy. In order to treat the patient's bulky disease and leptomeningeal spread while avoiding the potential toxicities of repeat whole brain radiation, the patient was treated with frameless stereotactic radiosurgery and intrathecal chemotherapy. This is the first report of this treatment approach for leptomeningeal relapse of breast cancer. The patient had an excellent response to treatment and durable intracranial control.

  15. Clinical results of stereotactic heavy-charged-particle radiosurgery for intracranial angiographically occult vascular malformations

    Energy Technology Data Exchange (ETDEWEB)

    Levy, R.P.; Fabrikant, J.I.; Phillips, M.H.; Frankel, K.A.; Steinberg, G.K.; Marks, M.P.; DeLaPaz, R.L.; Chuang, F.Y.S.; Lyman, J.T.

    1989-12-01

    Angiographically occult vascular malformations (AOVMs) of the brain have been recognized for many years to cause neurologic morbidity and mortality. They generally become symptomatic due to intracranial hemorrhage, focal mass effect, seizures or headaches. The true incidence of AOVMs is unknown, but autopsy studies suggest that they are more common than high-flow angiographically demonstrable arteriovenous malformations (AVMs). We have developed stereotactic heavy-charged-particle Bragg peak radiosurgery for the treatment of inoperable intracranial vascular malformations, using the helium ion beams at the Lawrence Berkeley Laboratory 184-inch Synchrocyclotron and Bevatron. This report describes the protocol for patient selection, radiosurgical treatment planning method, clinical and neuroradiologic results and complications encountered, and discusses the strengths and limitations of the method. 10 refs., 1 fig.

  16. Evaluation of Reported Malignant Transformation of Vestibular Schwannoma: De Novo and After Stereotactic Radiosurgery or Surgery.

    Science.gov (United States)

    Maducdoc, Marlon M; Ghavami, Yaser; Linskey, Mark E; Djalilian, Hamid R

    2015-09-01

    To critically analyze each reported case of malignant transformation of vestibular schwannoma (VS) after either stereotactic radiosurgery (SRS) or microsurgery (MS). We searched the Pubmed/Medline database using the relevant key words vestibular schwannoma, acoustic neuroma, malignant, transformation, radiation, induced, stereotactic, radiosurgery, malignancy, GammaKnife, and CyberKnife and combinations thereof. Inclusion criteria for malignant transformation of VS after SRS included histopathology of initially benign VS, subsequent histopathology confirming malignant VS, reasonable latency period between malignancy and benign diagnoses. A neurotologist and a skull base neurosurgeon independently assessed each case report for quality, entry, exclusion criteria, and comparability of extracted data. We calculated median age, latency times, and survival times for each case report. Malignant transformation has been documented to occur after either SRS or MS. Eight cases were included that showed histopathologic evidence of malignant transformation after SRS and MS. Four cases of malignant transformation were included that demonstrated malignant transformation after MS only. Malignant transformation of VS can also occur de novo, and de novo malignant VSs are also encountered, which can confound a causal inference from either SRS or MS. Eighteen cases of primary malignant VS were included. Studies that were identified but not included in the review are summarized and tabulated. We found 12 studies of malignant transformation associated with NF2. The potential mechanism leading to malignant transformation of VS seems more obvious for SRS and is less understood for MS. Given a low incidence of de novo malignant schwannoma, the possibility that these are spontaneous events in either setting cannot be ruled out. Risk of malignant transformation of VS after either SRS or MS is not zero; however, the magnitude of this risk is probably minimal based on the evidence from eight

  17. Late clinical and radiological complications of stereotactical radiosurgery of arteriovenous malformations of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Parkhutik, Vera [Hospital Universitario la Fe, Department of Neurology, Valencia (Spain); Universidad Autonoma de Barcelona, PhD Program of the Department of Medicine, Barcelona (Spain); Lago, Aida; Vazquez, Juan Francisco; Tembl, Jose Ignacio [Hospital Universitario la Fe, Department of Neurology, Valencia (Spain); Aparici, Fernando; Guillen, Lourdes; Mainar, Esperanza; Vazquez, Victor [Hospital Universitario la Fe, Department of Neuroradiology, Valencia (Spain)

    2013-04-15

    Post-radiation injury of patients with brain arteriovenous malformations (AVM) include blood-brain barrier breakdown (BBBB), edema, and necrosis. Prevalence, clinical relevance, and response to treatment are poorly known. We present a series of consecutive brain AVM treated with stereotactic radiosurgery describing the appearance of radiation injury and clinical complications. Consecutive patients with annual clinical and radiological follow-up (median length 63 months). Edema and BBBB were classified in four groups (minimal, perilesional, moderate, or severe), and noted together with necrosis. Clinical symptoms of interest were intracranial hypertension, new neurological deficits, new seizures, and brain hemorrhages. One hundred two cases, median age 34 years, 52 % male. Median irradiated volume 3.8 cc, dose to the margin of the nidus 18.5 Gy. Nineteen patients underwent a second radiosurgery. Only 42.2 % patients remained free from radiation injury. Edema was found in 43.1 %, blood-brain barrier breakdown in 20.6 %, necrosis in 6.9 %. Major injury (moderate or severe edema, moderate or severe BBBB, or necrosis) was found in 20 of 102 patients (19.6 %). AVM diameter >3 cm and second radiosurgery were independent predictors. Time to the worst imaging was 60 months. Patients with major radiation injury had a hazard ratio for appearance of focal deficits of 7.042 (p = 0.04), of intracranial hypertension 2.857 (p = 0.025), hemorrhage into occluded nidus 9.009 (p = 0.079), appearance of new seizures not significant. Major radiation injury is frequent and increases the risk of neurological complications. Its late appearance implies that current follow-up protocols need to be extended in time. (orig.)

  18. Clinical results of LINAC-based stereotactic radiosurgery for pituitary adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, Julia; Yoshida, Masanori; Shioura, Hiroki; Kawamura, Yasutaka; Ito, Harumi; Takeuchi, Hiroaki; Kubota, Toshihiko [Fukui Medical Univ., Matsuoka (Japan); Maruyama, Ichiro [The Wakasa Wan Energy Research Center, Tsuruga, Fukui (Japan)

    2003-05-01

    We retrospectively evaluated our clinical results of stereotactic radiosurgery (SRS) for pituitary adenoma. Between 1995 and 2000, 13 patients were treated with SRS for pituitary adenoma. In all cases, the tumors had already been surgically resected. The adenomas were functional in 5 and non-functional in 8 patients. The median follow-up period was 30 months. SRS was performed with the use of a dedicated stereotactic 10-MV linear accelerator (LINAC). The median dose to the tumor margin was 15 Gy. The dose to the optic apparatus was limited to less than 8 Gy. MR images of 12 patients revealed tumor complete response (CR) in one case and partial response (PR) in 9 cases; in the remaining two patients, tumor size decreased by less than 50%. There was no recognizable regrowth of any of the tumors. In two of four GH-secreting adenomas, hormonal overproduction normalized, while the other two showed reduced hormonal production. One PRL-secreting adenoma did not respond. Reduction of visual acuity and field was seen in one patient. This patient also had a brain infarction. None of the patients developed brain radionecrosis or radiation-induced hypopituitarism. Although further studies based on greater numbers of cases and longer follow-up periods are needed, our results suggest that SRS seems to be a safe, effective treatment for pituitary adenoma. (author)

  19. The geometric accuracy of frameless stereotactic radiosurgery using a 6D robotic couch system

    Energy Technology Data Exchange (ETDEWEB)

    Takakura, T; Nakata, M; Yano, S; Fujimoto, T [Division of Clinical Radiology Service, Kyoto University Hospital, Kyoto (Japan); Mizowaki, T; Miyabe, Y; Nakamura, M; Hiraoka, M [Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan)], E-mail: toru1@kuhp.kyoto-u.ac.jp

    2010-01-07

    The aim of this paper is to assess the overall geometric accuracy of the Novalis system using the Robotic Tilt Module in terms of the uncertainty in frameless stereotactic radiotherapy. We analyzed the following three metrics: (1) the correction accuracy of the robotic couch, (2) the uncertainty of the isocenter position with gantry and couch rotation, and (3) the shift in position between the isocenter and central point detected with the ExacTrac x-ray system. Based on the concept of uncertainty, the overall accuracy was calculated from these values. The accuracy in positional correction with the robotic couch was 0.07 {+-} 0.22 mm, the positional shift of the isocenter associated with gantry rotation was 0.35 mm, the positional shift of the isocenter associated with couch rotation was 0.38 mm and the difference in position between the isocenter and the ExacTrac x-ray system was 0.30 mm. The accuracy of intracranial stereotactic radiosurgery with the Novalis system in our clinic was 0.31 {+-} 0.77 mm. The overall geometric accuracy based on the concept of uncertainty was 0.31 {+-} 0.77 mm, which is within the tolerance given in the American Association of Physicists in Medicine report no. 54.

  20. Early experiences of planning stereotactic radiosurgery using 3D printed models of eyes with uveal melanomas.

    Science.gov (United States)

    Furdová, Alena; Sramka, Miron; Thurzo, Andrej; Furdová, Adriana

    2017-01-01

    The objective of this study was to determine the use of 3D printed model of an eye with intraocular tumor for linear accelerator-based stereotactic radiosurgery. The software for segmentation (3D Slicer) created virtual 3D model of eye globe with tumorous mass based on tissue density from computed tomography and magnetic resonance imaging data. A virtual model was then processed in the slicing software (Simplify3D(®)) and printed on 3D printer using fused deposition modeling technology. The material that was used for printing was polylactic acid. In 2015, stereotactic planning scheme was optimized with the help of 3D printed model of the patient's eye with intraocular tumor. In the period 2001-2015, a group of 150 patients with uveal melanoma (139 choroidal melanoma and 11 ciliary body melanoma) were treated. The median tumor volume was 0.5 cm(3) (0.2-1.6 cm(3)). The radiation dose was 35.0 Gy by 99% of dose volume histogram. The 3D printed model of eye with tumor was helpful in planning the process to achieve the optimal scheme for irradiation which requires high accuracy of defining the targeted tumor mass and critical structures.

  1. A quality assurance program in stereotactic radiosurgery using the gamma knife unit

    Energy Technology Data Exchange (ETDEWEB)

    Stuecklschweiger, G.F.; Feichtinger, K. [Universitaetsklinik fuer Radiologie, Graz (Austria). Klinische Abt. fuer Strahlentherapie

    1998-10-01

    Because of the large single fraction dose in stereotactic radiosurgery it is important to guarantee a high geometric and dosimetric accuracy. The paper represent the quality assurance program for the Gamma Knife unit at the University Clinic of Neurosurgery in Graz. The program includes the following procedures: Timer control, mechanical radiation isocenter coincidence, trunnion centricity, helmet microswitches test, radiation output and relative helmet factors, dose profile verification, safety interlocks checks and software quality assurance. In summary, the mechanical accuracy and reproducibility of the Gamma Knife unit are <1 mm. The geometric failure in stereotactic Gamma Knife treatment is limited by the human error in setting the clinical target volume and the spatial accuracy of dose delivery to the patient is limited by the accuracy of modern target localization procedures. (orig.) [Deutsch] Wegen der bei der stereotaktischen Radiochirurgie verabreichten hohen Einzeldosis ist es wichtig, eine hohe geometrische und dosimetrische Genauigkeit zu gewaehrleisten. In der vorliegenden Arbeit wird das Qualitaetssicherungsprogramm fuer die Gamma-Knife-Einheit an der Universitaetsklinik fuer Neurochirurgie in Graz vorgestellt. Das Programm umfasst folgende Prozesse: Kontrolle der Zeitschaltuhr, der Uebereinstimmung des mechanischen Isozentrums mit dem Schnittpunkt der Zentralstrahlen aller Quellen, die Zentrizitaet der x-Achsenverbindung, der Mikroschalter, der Output- und relativen Helmfaktoren, der Dosisprofile, der Sicherheitsfunktionen und der Bestrahlungsplanungssoftware. Zusammenfassend kann gesagt werden, dass die mechanische Genauigkeit und Reproduzierbarkeit am Gammaknife<1 mm sind. Die geometrische Genauigkeit wird durch die Genauigkeit der Einzeichnung der klinischen Zielvolumina und die Genauigkeit der Dosisverteilung im Patienten durch die Genauigkeit der verwendeten Lokalisationsgeraete begrenzt. (orig.)

  2. The geometric accuracy of frameless stereotactic radiosurgery using a 6D robotic couch system.

    Science.gov (United States)

    Takakura, T; Mizowaki, T; Nakata, M; Yano, S; Fujimoto, T; Miyabe, Y; Nakamura, M; Hiraoka, M

    2010-01-07

    The aim of this paper is to assess the overall geometric accuracy of the Novalis system using the Robotic Tilt Module in terms of the uncertainty in frameless stereotactic radiotherapy. We analyzed the following three metrics: (1) the correction accuracy of the robotic couch, (2) the uncertainty of the isocenter position with gantry and couch rotation, and (3) the shift in position between the isocenter and central point detected with the ExacTrac x-ray system. Based on the concept of uncertainty, the overall accuracy was calculated from these values. The accuracy in positional correction with the robotic couch was 0.07 +/- 0.22 mm, the positional shift of the isocenter associated with gantry rotation was 0.35 mm, the positional shift of the isocenter associated with couch rotation was 0.38 mm and the difference in position between the isocenter and the ExacTrac x-ray system was 0.30 mm. The accuracy of intracranial stereotactic radiosurgery with the Novalis system in our clinic was 0.31 +/- 0.77 mm. The overall geometric accuracy based on the concept of uncertainty was 0.31 +/- 0.77 mm, which is within the tolerance given in the American Association of Physicists in Medicine report no. 54.

  3. Early experiences of planning stereotactic radiosurgery using 3D printed models of eyes with uveal melanomas

    Science.gov (United States)

    Furdová, Alena; Sramka, Miron; Thurzo, Andrej; Furdová, Adriana

    2017-01-01

    Objective The objective of this study was to determine the use of 3D printed model of an eye with intraocular tumor for linear accelerator-based stereotactic radiosurgery. Methods The software for segmentation (3D Slicer) created virtual 3D model of eye globe with tumorous mass based on tissue density from computed tomography and magnetic resonance imaging data. A virtual model was then processed in the slicing software (Simplify3D®) and printed on 3D printer using fused deposition modeling technology. The material that was used for printing was polylactic acid. Results In 2015, stereotactic planning scheme was optimized with the help of 3D printed model of the patient’s eye with intraocular tumor. In the period 2001–2015, a group of 150 patients with uveal melanoma (139 choroidal melanoma and 11 ciliary body melanoma) were treated. The median tumor volume was 0.5 cm3 (0.2–1.6 cm3). The radiation dose was 35.0 Gy by 99% of dose volume histogram. Conclusion The 3D printed model of eye with tumor was helpful in planning the process to achieve the optimal scheme for irradiation which requires high accuracy of defining the targeted tumor mass and critical structures. PMID:28203052

  4. Stereotactic radiosurgery planning based on time-resolved CTA for arteriovenous malformation: a case report and review of the literature.

    Science.gov (United States)

    Turner, Ryan C; Lucke-Wold, Brandon P; Josiah, Darnell; Gonzalez, Javier; Schmidt, Matthew; Tarabishy, Abdul Rahman; Bhatia, Sanjay

    2016-08-01

    Stereotactic radiosurgery has long been recognized as the optimal form of management for high-grade arteriovenous malformations not amenable to surgical resection. Radiosurgical plans have generally relied upon the integration of stereotactic magnetic resonance angiography (MRA), standard contrast-enhanced magnetic resonance imaging (MRI), or computed tomography angiography (CTA) with biplane digital subtraction angiography (DSA). Current options are disadvantageous in that catheter-based biplane DSA is an invasive test associated with a small risk of complications and perhaps more importantly, the two-dimensional nature of DSA is an inherent limitation in creating radiosurgical contours. The necessity of multiple scans to create DSA contours for radiosurgical planning puts patients at increased risk. Furthermore, the inability to import two-dimensional plans into some radiosurgery programs, such as Cyberknife TPS, limits treatment options for patients. Defining the nidus itself is sometimes difficult in any of the traditional modalities as all draining veins and feeding arteries are included in the images. This sometimes necessitates targeting a larger volume, than strictly necessary, with stereotactic radiosurgery for treatment of the AVM. In this case report, we show the ability to use a less-invasive and three-dimensional form of angiography based on time-lapsed CTA (4D-CTA) rather than traditional DSA for radiosurgical planning. 4D-CTA may allow generation of a series of images, which can show the flow of contrast through the AVM. A review of these series may allow the surgeon to pick and use a volume set that best outlines the nidus with least interference from feeding arteries or draining veins. In addition, 4D-CTA scans can be uploaded into radiosurgery programs and allow three-dimensional targeting. This is the first reported case demonstrating the use of a 4D CTA and an MRI to delineate the AVM nidus for Gamma Knife radiosurgery, with complete

  5. Intracranial stereotactic radiosurgery with an adapted linear accelerator vs. robotic radiosurgery: Comparison of dosimetric treatment plan quality.

    Science.gov (United States)

    Treuer, Harald; Hoevels, Moritz; Luyken, Klaus; Visser-Vandewalle, Veerle; Wirths, Jochen; Kocher, Martin; Ruge, Maximilian

    2015-06-01

    Stereotactic radiosurgery with an adapted linear accelerator (linac-SRS) is an established therapy option for brain metastases, benign brain tumors, and arteriovenous malformations. We intended to investigate whether the dosimetric quality of treatment plans achieved with a CyberKnife (CK) is at least equivalent to that for linac-SRS with circular or micromultileaf collimators (microMLC). A random sample of 16 patients with 23 target volumes, previously treated with linac-SRS, was replanned with CK. Planning constraints were identical dose prescription and clinical applicability. In all cases uniform optimization scripts and inverse planning objectives were used. Plans were compared with respect to coverage, minimal dose within target volume, conformity index, and volume of brain tissue irradiated with ≥ 10 Gy. Generating the CK plan was unproblematic with simple optimization scripts in all cases. With the CK plans, coverage, minimal target volume dosage, and conformity index were significantly better, while no significant improvement could be shown regarding the 10 Gy volume. Multiobjective comparison for the irradiated target volumes was superior in the CK plan in 20 out of 23 cases and equivalent in 3 out of 23 cases. Multiobjective comparison for the treated patients was superior in the CK plan in all 16 cases. The results clearly demonstrate the superiority of the irradiation plan for CK compared to classical linac-SRS with circular collimators and microMLC. In particular, the average minimal target volume dose per patient, increased by 1.9 Gy, and at the same time a 14% better conformation index seems to be an improvement with clinical relevance.

  6. Long-term outcome of moderate hypofractionated stereotactic radiotherapy for meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Maranzano, Ernesto; Draghini, Lorena; Casale, Michelina; Arcidiacono, Fabio; Anselmo, Paola; Trippa, Fabio; Giorgi, Cesare [Hospital, Radiotherapy Oncology Centre, Terni (Italy)

    2015-12-15

    The aim of this work was to evaluate long-term results of moderate hypofractionated stereotactic radiotherapy (hFSRT) for intracranial meningiomas. In all, 77 consecutive patients with 80 lesions were included. Median age was 65 years (range 23-82 years), male/female ratio was 21/56, and the median Karnofsky performance status was 90 (range 60-100). In 31 lesions (39 %), diagnosis was based upon clinical and radiological data; 37 lesions were histologically proven as World Health Organization (WHO) grade I and 12 grade II meningiomas. Median treatment volume was 23 cc. Prescribed doses were 45 Gy in 15 fractions of 3 Gy (15 x 3 Gy) or 42 Gy in 14 fractions of 3 Gy (14 x 3 Gy). After a median follow-up of 56 months, 49 (61 %) lesions received 14 x 3 Gy and 31 (39 %) 15 x 3 Gy. Local control (LC) rate remained unchanged at 84 % at 5 and 10 years. Overall survival and disease-specific survival (DSS) were 76 and 93 % at 5 years, 72 and 89 % at 10 years, respectively. With univariate analysis, previous surgery and WHO grade II tumor were negative prognostic factors for LC and DSS. With multivariate analysis only tumor grade was an independent prognostic factor for LC. No clinically significant acute and/or late toxicities were observed. Moderate hFSRT was effective and safe with an excellent tolerance profile. It can be an alternative treatment option for patients with recurrent or inoperable large meningiomas. The low number of fractions administered with hFSRT led to reduce treatment-related discomfort for patients. Grade II tumor and previous surgery were negative prognosis factors. (orig.) [German] Untersucht wurden die Langzeitergebnisse von moderater hypofraktionierter stereotaktischer Strahlentherapie (hFSRT) bei intrakraniellen Meningeomen. Es wurden 77 konsekutive Patienten mit 80 Laesionen ausgewaehlt. Das durchschnittliche Alter betrug 65 Jahre (Spanne 23-82 Jahre), das Verhaeltnis Maenner/Frauen lag bei 21/56, der mediane Karnofsky-Index betrug 90 (Spanne 60

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

    CERN Document Server

    Zhang, Qinghui; Burman, Chandra; Song, Yulin; Zhang, Mutian

    2013-01-01

    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).

  8. A round-robin gamma stereotactic radiosurgery dosimetry interinstitution comparison of calibration protocols

    Energy Technology Data Exchange (ETDEWEB)

    Drzymala, R. E., E-mail: drzymala@wustl.edu [Department of Radiation Oncology, Washington University, St. Louis, Missouri 63110 (United States); Alvarez, P. E. [Imaging and Radiation Oncology Core Houston, UT MD Anderson Cancer Center, Houston, Texas 77030 (United States); Bednarz, G. [Radiation Oncology Department, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15232 (United States); Bourland, J. D. [Department of Radiation Oncology, Wake Forest University, Winston-Salem, North Carolina 27157 (United States); DeWerd, L. A. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); Ma, L. [Department of Radiation Oncology, University California San Francisco, San Francisco, California 94143 (United States); Meltsner, S. G. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Neyman, G. [Department of Radiation Oncology, The Cleveland Clinic Foundation, Cleveland, Ohio 44195 (United States); Novotny, J. [Medical Physics Department, Hospital Na Homolce, Prague 15030 (Czech Republic); Petti, P. L. [Gamma Knife Center, Washington Hospital Healthcare System, Fremont, California 94538 (United States); Rivard, M. J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States); Shiu, A. S. [Department of Radiation Oncology, University of Southern California, Los Angeles, California 90033 (United States); Goetsch, S. J. [San Diego Medical Physics, Inc., La Jolla, California 92037 (United States)

    2015-11-15

    Purpose: Absorbed dose calibration for gamma stereotactic radiosurgery is challenging due to the unique geometric conditions, dosimetry characteristics, and nonstandard field size of these devices. Members of the American Association of Physicists in Medicine (AAPM) Task Group 178 on Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance have participated in a round-robin exchange of calibrated measurement instrumentation and phantoms exploring two approved and two proposed calibration protocols or formalisms on ten gamma radiosurgery units. The objectives of this study were to benchmark and compare new formalisms to existing calibration methods, while maintaining traceability to U.S. primary dosimetry calibration laboratory standards. Methods: Nine institutions made measurements using ten gamma stereotactic radiosurgery units in three different 160 mm diameter spherical phantoms [acrylonitrile butadiene styrene (ABS) plastic, Solid Water, and liquid water] and in air using a positioning jig. Two calibrated miniature ionization chambers and one calibrated electrometer were circulated for all measurements. Reference dose-rates at the phantom center were determined using the well-established AAPM TG-21 or TG-51 dose calibration protocols and using two proposed dose calibration protocols/formalisms: an in-air protocol and a formalism proposed by the International Atomic Energy Agency (IAEA) working group for small and nonstandard radiation fields. Each institution’s results were normalized to the dose-rate determined at that institution using the TG-21 protocol in the ABS phantom. Results: Percentages of dose-rates within 1.5% of the reference dose-rate (TG-21 + ABS phantom) for the eight chamber-protocol-phantom combinations were the following: 88% for TG-21, 70% for TG-51, 93% for the new IAEA nonstandard-field formalism, and 65% for the new in-air protocol. Averages and standard deviations for dose-rates over all measurements relative to the TG-21 + ABS

  9. Dosimetry analysis of small radiation fields in stereotactic radiosurgery of the brain

    Science.gov (United States)

    Al-Najjar, Waleed Hassan

    Accurate dosimetric data of narrow circular photon beams are needed for stereotactic radiosurgery of brain tumors. However, the measurement of dosimetric data of narrow circular beams is beset with several constraints. Usually, 6 MV photon beams produced by isocentric linear accelerators are mostly used for routine radiosurgery although other photon energies are available. Systematic dosimetric studies were performed on 12.5, 20, 30 and 40 mm diameter collimators using different measuring techniques in order to examine the possible accuracies associated in the measured dosimetric data of narrow circular photon beams. In addition, the relative suitabilities of 4, 6 and 10 MV photon beams for stereotactic radiosurgery were assessed. The lack of electronic equilibrium and steep dose gradient effects were found to be minimal for a 4 MV photon beam compared to the 6 and 10 MV photon beams. The measured output factors with a small volume (0.02 cc) ionization chamber were found to agree with film and MOSFET (Metal Oxide Semiconductor Field Effect Transistor) detector measurements for 4 MV photon beam even for smaller field sizes. The measured beam profiles were also found to be in better agreement with the expected shapes for the 4 MV beam than for 6 and 10 MV beams. The 80% isodose volumes for a typical 20.0 mm diameter field for 1 to 10 non-coplanar converging arcs showed that the volumes for the 4 MV beam are slightly larger than the corresponding volumes for the 6 and 10 MV photon beams for any given isodose level. The dose fall- off distances from the 80% to 50% isodoses are also, in general, found to be smaller for the 4 MV beam. Therefore, for radiosurgery, the dose calculations for the 4 MV beam have less uncertainty than the dose calculations for the 6 and 10 MV beams. The output factors can be measured with an ionization chamber for the 4 MV photon beam over the range 12.5 to 40.0 mm diameter field size, whereas for the 6 MV beam they can only be measured for

  10. Stereotactic Hypofractionated Irradiation for Metastatic, Inoperable, and Recurrent Malignancies: A Modern Necessity, rather than a Luxury

    Directory of Open Access Journals (Sweden)

    Sridhar P. Susheela

    2014-01-01

    Full Text Available Stereotactic-irradiation combines highly conformal delivery of radiation to selected volumes at large doses per fraction, with the treatment completed typically within one to five fractions. The radiobiological equivalence of doses delivered by stereotactic-irradiation (often beyond 80–100 Gy is much higher in comparison to the doses achievable by conventional fractionation. At the high fraction sizes used in stereotactic-irradiation, evidence suggests the role of various radiobiological mechanisms of actions, which are not traditionally relatable with conventional radiotherapy. In spite of the accumulating evidence in favour of the efficacy of stereotactic irradiation in terms of improving local control and at times attaining increments in survival, the clinical adoption of the technique remains dismal. This review provides a brief description of the available evidence describing the benefits of stereotactic-irradiation for the management of patients with oligometastases, unresectable malignancies and for disease recurrence after prior radiotherapy. Given the growing body of evidence illustrating the efficacy of stereotactic irradiation among patients with conditions which were previously often regarded as untreatable, it is likely that the widespread adoption of stereotactic irradiation may achieve cure in a few patients, while in the remainder providing prospects of long term local control. This could be a step in the direction of converting incurable malignancies into chronic controllable diseases.

  11. INTER- AND INTRAFRACTION MOTION FOR STEREOTACTIC RADIOSURGERY IN DOGS AND CATS USING A MODIFIED BRAINLAB FRAMELESS STEREOTACTIC MASK SYSTEM.

    Science.gov (United States)

    Dieterich, Sonja; Zwingenberger, Allison; Hansen, Katherine; Pfeiffer, Isabella; Théon, Alain; Kent, Michael S

    2015-01-01

    Precise and accurate patient positioning is necessary when doing stereotactic radiosurgery (SRS) to ensure adequate dosing to the tumor and sparing of normal tissues. This prospective cross-sectional study aimed to assess feasibility of a commercially available modified frameless SRS positioning system for use in veterinary radiotherapy patients with brain tumors. Fifty-one dogs and 12 cats were enrolled. Baseline and verification CT images were acquired. The verification CT images from 32 dogs and five cats had sufficient images for fusion to baseline CT images. A rigid box-based fusion was performed to determine interfraction motion. Forty-eight dogs and 11 cats were assessed for intrafraction motion by cine CT. Seventy percent of dogs and 60% of cats had interfraction 3D vector translational shifts >1 mm, with mean values of 1.9 mm in dogs, and 1.8 mm in cats. In dogs muscle wasting was weakly correlated with translational shifts. The maximum angular interfraction motion observed was 6.3° (roll), 3.5° (pitch), and 3.3° (yaw). There was no correlation between angular interfraction motion and weight, brachycephaly, or muscle wasting. Fifty-seven percent of dogs and 50% of cats had respiration-related intrafraction motion. Of these, 4.5% of dogs and 10% of cats had intrafraction motion >1 mm. This study demonstrates the modified Brainlab system is feasible for SRS in dogs and cats. The smaller cranial size and difference in anatomy increases setup uncertainty in some animals beyond limits usually accepted in SRS. Image-guided positioning is recommended to achieve clinically acceptable setup accuracy (<1 mm) for SRS. © 2015 American College of Veterinary Radiology.

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

    Energy Technology Data Exchange (ETDEWEB)

    Leavitt, Jacqueline A., E-mail: leavitt.jacqueline@mayo.edu [Department of Ophthalmology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Stafford, Scott L. [Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Link, Michael J. [Department of Neurosurgery, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Pollock, Bruce E. [Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Department of Neurosurgery, Mayo Clinic and Foundation, Rochester, Minnesota (United States)

    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.

  13. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Young, E-mail: eyhan@uams.edu [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Zhang Xin; Yan Yulong; Sharma, Sunil; Penagaricano, Jose [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Moros, Eduardo [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States); Corry, Peter [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States)

    2012-01-01

    At University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

  14. Silent Corticotroph Adenomas After Stereotactic Radiosurgery: A Case–Control Study

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhiyuan; Ellis, Scott; Lee, Cheng-Chia; Starke, Robert M. [Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia (United States); Schlesinger, David [Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia (United States); Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia (United States); Lee Vance, Mary [Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia (United States); Department of Internal Medicine, University of Virginia, Charlottesville, Virginia (United States); Lopes, M. Beatriz [Division of Neuropathology, University of Virginia, Charlottesville, Virginia (United States); Sheehan, Jason, E-mail: jsheehan@virginia.edu [Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia (United States); Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia (United States)

    2014-11-15

    Purpose: To investigate the safety and effectiveness of stereotactic radiosurgery (SRS) in patients with a silent corticotroph adenoma (SCA) compared with patients with other subtypes of non–adrenocorticotropic hormone staining nonfunctioning pituitary adenoma (NFA). Methods and Materials: The clinical features and outcomes of 104 NFA patients treated with SRS in our center between September 1994 and August 2012 were evaluated. Among them, 34 consecutive patients with a confirmatory SCA were identified. A control group of 70 patients with other subtypes of NFA were selected for review based on comparable baseline features, including sex, age at the time of SRS, tumor size, margin radiation dose to the tumor, and duration of follow-up. Results: The median follow-up after SRS was 56 months (range, 6-200 months). No patients with an SCA developed Cushing disease during the follow-up. Tumor control was achieved in 21 of 34 patients (62%) in the SCA group, compared with 65 of 70 patients (93%) in the NFA group. The median progression-free survival (PFS) was 58 months in the SCA group. The actuarial PFS was 73%, 46%, and 31% in the SCA group and was 94%, 87%, and 87% in the NFA group at 3, 5, and 8 years, respectively. Silent corticotroph adenomas treated with a dose of ≥17 Gy exhibited improved PFS. New-onset loss of pituitary function developed in 10 patients (29%) in the SCA group, whereas it occurred in 18 patients (26%) in the NFA group. Eight patients (24%) in the SCA group experienced worsening of a visual field deficit or visual acuity attributed to the tumor progression, as did 6 patients (9%) in the NFA group. Conclusion: Silent corticotroph adenomas exhibited a more aggressive course with a higher progression rate than other subtypes of NFAs. Stereotactic radiosurgery is an important adjuvant treatment for control of tumor growth. Increased radiation dose may lead to improved tumor control in SCA patients.

  15. Advances in treatment techniques: stereotactic body radiation therapy and the spread of hypofractionation.

    Science.gov (United States)

    Kavanagh, Brian D; Miften, Moyed; Rabinovitch, Rachel A

    2011-01-01

    Radiation therapy (RT) is an essential component of the management of many cancers. Traditionally, a course of external bream RT often involved daily treatments for a duration of 6 weeks or longer in some instances. Now, however, emerging clinical evidence indicates that, for some common cancers, the total length of treatment can be substantially shortened, offering convenience to patients and opportunities for resource utilization efficiencies. This trend toward so-called hypofractionated RT has been supported by hypothesis-driven clinical research guided by a combination of radiobiological and clinical insights and technological enhancements. The present review presents the rationale behind and current status of hypofractionation for prostate, breast, and medically inoperable early stage lung cancer.

  16. Surgery Versus Stereotactic Radiosurgery for Single Synchronous Brain Metastasis from Non-Small Cell Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    Hui LI; Sheng-cai HOU; Bin HU; Tong LI; Yang Wang; Jin-bai Miao; Bin You; Yi-li Fu

    2009-01-01

    Objective: The aim of this study is to compare the effectiveness of surgery with stereotactic radiosurgery (SRS) for patients with a single synchronous brain metastasis from successfully treated non-small cell lung cancer.Methods: Between 1995 and 2002, 53 patients underwent resection of both primary non-small cell lung cancer and the associated single brain metastasis. There were 33 men and 20 women with a mean age of 57 years (range, 32(85 years). At the time of diagnosis, 42 patients experienced lung cancer related symptoms, whereas 11 patients experienced brain metastases-related symptoms. 42 patients had received thoracic surgery first, and 11 patients had undergone neurosurgery or radiosurgery first. Pneumonectomy was performed in 9 out of 42 patients (21.4%), lobectomies in 30 (71.4%), and wedge resection in 3 (7.2%). 48 patients (90.5%) underwent complete lymphadenectomy. 35 patients underwent brain metastasectomy. 18 underwent SRS.Results: There was no postoperative mortality and severe complications after either lung or brain surgery. Histology showed 34 adenocarcinomas, 16 squamous cell carcinomas, and 3 large cell lung cancers. 15 patients (28.3%) had no evidence of lymph node metastases (N0), 20 patients (37.7%) had hilar metastases (N1), and 18 patients (34%) had mediastinal metastases (N2). The 1-, 2-, 3- and 5-year overall survival rates were 49%, 19%, 10%, and 5%, respectively. The corresponding data for neurosurgery group were 55%, 17%, 11%, and 6%, respectively. The median survival time was 13 months. For SRS group the corresponding data were 44.8%, 20.9% 10.5%, and 2%, respectively. The median survival time was 14 months. The differences between the two groups were not significant (P>0.05). In lymph node negative patients (N0), the overall 5-year survival rate was 10%, as compared with a 1% survival rate in patients with lymph node metastases (N1(2). The difference was significant (P0.05).Conclusion: Although the overall survival rate for

  17. Multistage stereotactic radiosurgery for large cerebral arteriovenous malformations using the Gamma Knife platform.

    Science.gov (United States)

    Ding, Chuxiong; Hrycushko, Brian; Whitworth, Louis; Li, Xiang; Nedzi, Lucien; Weprin, Bradley; Abdulrahman, Ramzi; Welch, Babu; Jiang, Steve B; Wardak, Zabi; Timmerman, Robert D

    2017-07-06

    Radiosurgery is an established technique to treat cerebral arteriovenous malformations (AVMs). Obliteration of larger AVMs (> 10-15 cm(3) or diameter > 3 cm) in a single session is challenging with current radiosurgery platforms due to toxicity. We present a novel technique of multistage stereotactic radiosurgery (SRS) for large intracranial arteriovenous malformations (AVM) using the Gamma Knife system. Eighteen patients with large (> 10-15 cm(3) or diameter > 3 cm) AVMs, which were previously treated using a staged SRS technique on the Cyberknife platform, were retrospectively selected for this study. The AVMs were contoured and divided into 3-8 subtargets to be treated sequentially in a staged approach at half to 4 week intervals. The prescription dose ranged from 15 Gy to 20 Gy, depending on the subtarget number, volume, and location. Gamma Knife plans using multiple collimator settings were generated and optimized. The coordinates of each shot from the initial plan covering the total AVM target were extracted based on their relative positions within the frame system. The shots were regrouped based on their location with respect to the subtarget contours to generate subplans for each stage. The delivery time of each shot for a subtarget was decay corrected with (60) Co for staging the treatment course to generate the same dose distribution as that planned for the total AVM target. Conformality indices and dose-volume analysis were performed to evaluate treatment plans. With the shot redistribution technique, the composite dose for the multistaged treatment of multiple subtargets is equivalent to the initial plan for total AVM target. Gamma Knife plans resulted in an average PTV coverage of 96.3 ± 0.9% and a PITV of 1.23 ± 0.1. The resulting Conformality indices, V12Gy and R50 dose spillage values were 0.76 ± 0.05, 3.4 ± 1.8, and 3.1 ± 0.5 respectively. The Gamma Knife system can deliver a multistaged conformal dose to treat large AVMs when correcting for

  18. Technical Note: Evaluation of the systematic accuracy of a frameless, multiple image modality guided, linear accelerator based stereotactic radiosurgery system

    Energy Technology Data Exchange (ETDEWEB)

    Wen, N., E-mail: nwen1@hfhs.org; Snyder, K. C.; Qin, Y.; Li, H.; Siddiqui, M. S.; Chetty, I. J. [Department of Radiation Oncology, Henry Ford Health System, 2799 West Brand Boulevard, Detroit, Michigan 48202 (United States); Scheib, S. G.; Schmelzer, P. [Varian Medical System, Täfernstrasse 7, Dättwil AG 5405 (Switzerland)

    2016-05-15

    Purpose: To evaluate the total systematic accuracy of a frameless, image guided stereotactic radiosurgery system. Methods: The localization accuracy and intermodality difference was determined by delivering radiation to an end-to-end prototype phantom, in which the targets were localized using optical surface monitoring system (OSMS), electromagnetic beacon-based tracking (Calypso®), cone-beam CT, “snap-shot” planar x-ray imaging, and a robotic couch. Six IMRT plans with jaw tracking and a flattening filter free beam were used to study the dosimetric accuracy for intracranial and spinal stereotactic radiosurgery treatment. Results: End-to-end localization accuracy of the system evaluated with the end-to-end phantom was 0.5 ± 0.2 mm with a maximum deviation of 0.9 mm over 90 measurements (including jaw, MLC, and cone measurements for both auto and manual fusion) for single isocenter, single target treatment, 0.6 ± 0.4 mm for multitarget treatment with shared isocenter. Residual setup errors were within 0.1 mm for OSMS, and 0.3 mm for Calypso. Dosimetric evaluation based on absolute film dosimetry showed greater than 90% pass rate for all cases using a gamma criteria of 3%/1 mm. Conclusions: The authors’ experience demonstrates that the localization accuracy of the frameless image-guided system is comparable to robotic or invasive frame based radiosurgery systems.

  19. Risk factors for leptomeningeal carcinomatosis in patients with brain metastases who have previously undergone stereotactic radiosurgery.

    Science.gov (United States)

    Huang, Andrew J; Huang, Karen E; Page, Brandi R; Ayala-Peacock, Diandra N; Lucas, John T; Lesser, Glenn J; Laxton, Adrian W; Tatter, Stephen B; Chan, Michael D

    2014-10-01

    Our objective was to explore the hypothesis that the risk of leptomeningeal dissemination (LMD) in patients who underwent stereotactic radiosurgery (SRS) for brain metastases is influenced by the site of the primary cancer, the addition of whole brain radiation therapy (WBRT), surgical resection, and control over their systemic disease. We conducted a retrospective cohort analysis of 805 patients who were treated with SRS for brain metastases between 1999 and 2012 at the Wake Forest Baptist Medical Center, and excluded all patients with evidence of LMD before SRS. The primary outcome was LMD. Forty-nine of 795 patients developed LMD with a cumulative incidence of 6.2% (95% Confidence Interval (CI), 4.7-8.0). Median time from SRS to LMD was 7.4 months (Interquartile Range (IQR), 3.3-15.4). A colorectal primary site (Hazard Ratio (HR), 4.5; 95% CI 2.5-8.0; p LMD. There was no evidence that surgical resection before SRS altered the risk of LMD (HR, 1.1; 95 % CI 0.6-2.0, p = 0.78). In patients who underwent SRS for brain metastases, a colorectal or breast primary site, distant brain failure, younger age, and an increased number of intracranial metastases were independently associated with LMD. Given its relative rarity as an outcome, multi-institutional prospective studies will likely be necessary to validate and quantify these relationships.

  20. Microvascular Decompression Versus Stereotactic Radiosurgery for Trigeminal Neuralgia: A Decision Analysis

    Science.gov (United States)

    Berger, Ian; Nayak, Nikhil; Schuster, James; Lee, John; Stein, Sherman

    2017-01-01

    Introduction: Both microvascular decompression (MVD) and stereotactic radiosurgery (SRS) have been demonstrated to be effective in treating medically refractory trigeminal neuralgia. However, there is controversy over which one offers more durable pain relief and the patient selection for each treatment. We used a decision analysis model to calculate the health-related quality of life (QOL) for each treatment. Methods: We searched PubMed and the Cochrane Database of Systematic Reviews for relevant articles on MVD or SRS for trigeminal neuralgia published between 2000 and 2015. Using data from these studies, we modeled pain relief and complication outcomes and assigned QOL values. A sensitivity analysis using a Monte Carlo simulation determined which procedure led to the greatest QOL. Results: MVD produced a significantly higher QOL than SRS at a seven-year follow-up. Additionally, MVD patients had a significantly higher rate of complete pain relief and a significantly lower rate of complications and recurrence. Conclusions: With a decision-analytic model, we calculated that MVD provides more favorable outcomes than SRS for the treatment of trigeminal neuralgia. PMID:28280653

  1. Hearing Outcomes After Stereotactic Radiosurgery for Unilateral Intracanalicular Vestibular Schwannomas: Implication of Transient Volume Expansion

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dong Gyu, E-mail: gknife@plaza.snu.ac.kr [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Jung Ho [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Jeong-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Chae-Yong [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Paek, Sun Ha; Jung, Hee-Won [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2013-01-01

    Purpose: We evaluated the prognostic factors for hearing outcomes after stereotactic radiosurgery (SRS) for unilateral sporadic intracanalicular vestibular schwannomas (IC-VSs) as a clinical homogeneous group of VSs. Methods and Materials: Sixty consecutive patients with unilateral sporadic IC-VSs, defined as tumors in the internal acoustic canal, and serviceable hearing (Gardner-Roberson grade 1 or 2) were treated with SRS as an initial treatment. The mean tumor volume was 0.34 {+-} 0.03 cm{sup 3} (range, 0.03-1.00 cm{sup 3}), and the mean marginal dose was 12.2 {+-} 0.1 Gy (range, 11.5-13.0 Gy). The median follow-up duration was 62 months (range, 36-141 months). Results: The actuarial rates of serviceable hearing preservation were 70%, 63%, and 55% at 1, 2, and 5 years after SRS, respectively. In multivariate analysis, transient volume expansion of {>=}20% from initial tumor size was a statistically significant risk factor for loss of serviceable hearing and hearing deterioration (increase of pure tone average {>=}20 dB) (odds ratio = 7.638; 95% confidence interval, 2.317-25.181; P=.001 and odds ratio = 3.507; 95% confidence interval, 1.228-10.018; P=.019, respectively). The cochlear radiation dose did not reach statistical significance. Conclusions: Transient volume expansion after SRS for VSs seems to be correlated with hearing deterioration when defined properly in a clinically homogeneous group of patients.

  2. The effect of contouring variability on dosimetric parameters for brain metastases treated with stereotactic radiosurgery.

    Science.gov (United States)

    Stanley, Julia; Dunscombe, Peter; Lau, Harold; Burns, Paul; Lim, Gerald; Liu, Hong-Wei; Nordal, Robert; Starreveld, Yves; Valev, Boris; Voroney, Jon-Paul; Spencer, David P

    2013-12-01

    To quantify the effect of contouring variation on stereotactic radiosurgery plan quality metrics for brain metastases. Fourteen metastases, each contoured by 8 physicians, formed the basis of this study. A template-based dynamic conformal 5-arc dose distribution was developed for each of the 112 contours, and each dose distribution was applied to the 7 other contours in each patient set. Radiation Therapy Oncology Group (RTOG) plan quality metrics and the Paddick conformity index were calculated for each of the 896 combinations of dose distributions and contours. The ratio of largest to smallest contour volume for each metastasis varied from 1.25 to 4.47, with a median value of 1.68 (n=8). The median absolute difference in RTOG conformity index between the value for the reference contour and the values for the alternative contours was 0.35. The variation of the range of conformity index for all contours for a given tumor varied with the tumor size. The high degree of interobserver contouring variation strongly suggests that peer review or consultation should be adopted to standardize tumor volume prescription. Observer confidence was not reflected in contouring consistency. The impact of contouring variability on plan quality metrics, used as criteria for clinical trial protocol compliance, was such that the category of compliance was robust to interobserver effects only 70% of the time. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Stereotactic Radiosurgery with Neoadjuvant Embolization of Larger Arteriovenous Malformations: An Institutional Experience

    Directory of Open Access Journals (Sweden)

    Richard Dalyai

    2014-01-01

    Full Text Available Objective. This study investigates the safety and efficacy of a multimodality approach combining staged endovascular embolizations with subsequent SRS for the management of larger AVMs. Methods. Ninety-five patients with larger AVMs were treated with staged endovascular embolization followed by SRS between 1996 and 2011. Results. The median volume of AVM in this series was 28 cm3 and 47 patients (48% were Spetzler-Martin grade IV or V. Twenty-seven patients initially presented with hemorrhage. Sixty-one patients underwent multiple embolizations while a single SRS session was performed in 64 patients. The median follow-up after SRS session was 32 months (range 9–136 months. Overall procedural complications occurred in 14 patients. There were 13 minor neurologic complications and 1 major complication (due to embolization while four patients had posttreatment hemorrhage. Thirty-eight patients (40% were cured radiographically. The postradiosurgery actuarial rate of obliteration was 45% at 5 years, 56% at 7 years, and 63% at 10 years. In multivariate analysis, larger AVM size, deep venous drainage, and the increasing number of embolization/SRS sessions were negative predictors of obliteration. The number of embolizations correlated positively with the number of stereotactic radiosurgeries (P<0.005. Conclusions. Multimodality endovascular and radiosurgical approach is an efficacious treatment strategy for large AVM.

  4. Treatment of brain metastases of renal cell cancer with combined hypofractionated stereotactic radiotherapy and whole brain radiotherapy with hippocampal sparing.

    Science.gov (United States)

    Vrána, David; Študentová, Hana; Matzenauer, Marcel; Vlachová, Zuzana; Cwiertka, Karel; Gremlica, David; Kalita, Ondřej

    2016-06-01

    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.

  5. Stereotactic spine radiosurgery: Review of safety and efficacy with respect to dose and fractionation

    Science.gov (United States)

    Huo, Michael; Sahgal, Arjun; Pryor, David; Redmond, Kristin; Lo, Simon; Foote, Matthew

    2017-01-01

    Background: Stereotactic body radiotherapy (SBRT) is an emerging treatment option for spinal metastases with demonstrated efficacy in the upfront, postoperative, and re-treatment settings, as well as for tumor histologies considered radioresistant. Uncertainty exists regarding the optimal dose and fractionation schedule, with single and multifraction regimens commonly utilized. Methods: A literature search of the PubMed and Medline databases was conducted to identify papers specific to spine SBRT and the effect of varying dose/fractionation regimens on outcomes. Bibliographies of relevant papers were searched for further references, and international spine SBRT experts were consulted. Results: Local control rates generally exceed 80% at 1 year, while high rates of pain control have been attained. There is insufficient evidence to suggest superiority of either single or multiple fraction regimens with respect to local control and pain control. Low rates of toxicity have been reported, assuming strict dose constraints are respected. Radiation myelopathy may be the most morbid toxicity, although the rates are low. The risk of vertebral compression fracture appears to be associated with higher doses per fraction such as those used in single-fraction regimens. The Spinal Instability Neoplastic Score should be considered when evaluating patients for spine SBRT, and prophylactic stabilisation may be warranted. Pain flare is a relatively common toxicity which may be mediated with prophylactic dexamethasone. Because of the treatment complexity and potentially serious toxicities, strict quality assurance should occur at the organizational, planning, dosimetric, and treatment delivery levels. Conclusion: Both single and multifraction regimens are safe and efficacious in spine SBRT for spinal metastases. There may be advantages to hypofractionated treatment over single-fraction regimens with respect to toxicity. Ongoing investigation is underway to define optimal dose and

  6. Stereotactic radiosurgery in the palliative treatment of brain metastases; Radiocirurgia estereotatica no tratamento paliativo das metastases cerebrais

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Sergio L.; Souhami, Luis; Bahary, Jean-Paul; Clark, Brenda; Adamson, Nelson; Podgorsak, Ervin B. [McGill Univ., Montreal, PQ (Canada). Dept. of Oncology; Caron, Jean-Louis; Villemure, Jean-Guy; Olivier, Andre [McGill Univ., Montreal, PQ (Canada). Dept. of Neurosurgery

    1995-09-01

    Between October, 1988 and November, 1993, 57 patients with metastatic brain disease underwent stereotactic radiosurgery at McGill University, canada. Four patients were excluded from this analysis leaving a total of 53 evaluable patients (with 57 lesions). Radiosurgery was performed with the dynamic rotation technique which uses an isocentric, 10 MV, linear accelerator. A median dose of 1,800 c Gy was given in a single session. In 89% of the cases radiosurgery was used after failure to conventional brain radiotherapy. With a median follow-up of 6 months, the response rate was 65% . Treatments were well tolerated and only 4 patients (7%) developed late complications related to the therapy, with one patient requiring a surgical resection of an area of radionecrose. Radiosurgery appears to be and effective and safe treatment for selected patients with metastatic brain disease, recurrent post-conventional radiotherapy. Its value as a single treatment modality for patients with isolated brain metastasis is now being studied in prospective trials. (author). 29 refs., 4 figs., 4 tabs.

  7. Intracranial stereotactic radiosurgery with an adapted linear accelerator vs. robotic radiosurgery. Comparison of dosimetric treatment plan quality

    Energy Technology Data Exchange (ETDEWEB)

    Treuer, Harald; Hoevels, Moritz; Luyken, Klaus; Visser-Vandewalle, Veerle; Wirths, Jochen; Ruge, Maximilian [University Hospital Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); Kocher, Martin [University Hospital Cologne, Department of Radiotherapy, Cologne (Germany)

    2014-11-22

    Stereotactic radiosurgery with an adapted linear accelerator (linac-SRS) is an established therapy option for brain metastases, benign brain tumors, and arteriovenous malformations. We intended to investigate whether the dosimetric quality of treatment plans achieved with a CyberKnife (CK) is at least equivalent to that for linac-SRS with circular or micromultileaf collimators (microMLC). A random sample of 16 patients with 23 target volumes, previously treated with linac-SRS, was replanned with CK. Planning constraints were identical dose prescription and clinical applicability. In all cases uniform optimization scripts and inverse planning objectives were used. Plans were compared with respect to coverage, minimal dose within target volume, conformity index, and volume of brain tissue irradiated with ≥ 10 Gy. Generating the CK plan was unproblematic with simple optimization scripts in all cases. With the CK plans, coverage, minimal target volume dosage, and conformity index were significantly better, while no significant improvement could be shown regarding the 10 Gy volume. Multiobjective comparison for the irradiated target volumes was superior in the CK plan in 20 out of 23 cases and equivalent in 3 out of 23 cases. Multiobjective comparison for the treated patients was superior in the CK plan in all 16 cases. The results clearly demonstrate the superiority of the irradiation plan for CK compared to classical linac-SRS with circular collimators and microMLC. In particular, the average minimal target volume dose per patient, increased by 1.9 Gy, and at the same time a 14 % better conformation index seems to be an improvement with clinical relevance. (orig.) [German] Stereotaktische Radiochirurgie mit einem adaptierten Linearbeschleuniger (Linac-SRS) ist eine erfolgreiche und etablierte Therapieoption fuer Hirnmetastasen, benigne Hirntumoren und arteriovenoese Malformationen. Ziel war es, zu untersuchen, ob die mit einem CyberKnife (CK) erreichbare

  8. Safety and Efficacy of Stereotactic Radiosurgery and Adjuvant Bevacizumab in Patients With Recurrent Malignant Gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Cuneo, Kyle C. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Vredenburgh, James J.; Sampson, John H.; Reardon, David A.; Desjardins, Annick; Peters, Katherine B.; Friedman, Henry S. [Department of Surgery, Duke University Medical Center, Durham, NC (United States); Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC (United States); Willett, Christopher G. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Kirkpatrick, John P., E-mail: john.kirkpatrick@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC (United States)

    2012-04-01

    Purpose: Patients with recurrent malignant gliomas treated with stereotactic radiosurgery (SRS) and multiagent systemic therapies were reviewed to determine the effects of patient- and treatment-related factors on survival and toxicity. Methods and Materials: A retrospective analysis was performed on patients with recurrent malignant gliomas treated with salvage SRS from September 2002 to March 2010. All patients had experienced progression after treatment with temozolomide and radiotherapy. Salvage SRS was typically administered only after multiple postchemoradiation salvage systemic therapies had failed. Results: 63 patients were treated with SRS for recurrent high-grade glioma; 49 patients had World Health Organization (WHO) Grade 4 disease. Median follow-up was 31 months from primary diagnosis and 7 months from SRS. Median overall survival from primary diagnosis was 41 months for all patients. Median progression-free survival (PFS) and overall survival from SRS (OS-SRS) were 6 and 10 months for all patients, respectively. The 1-year OS-SRS for patients with Grade 4 glioma who received adjuvant (concurrent with or after SRS) bevacizumab was 50% vs. 22% for patients not receiving adjuvant bevacizumab (p = 0.005). Median PFS for patients with a WHO Grade 4 glioma who received adjuvant bevacizumab was 5.2 months vs. 2.1 months for patients who did not receive adjuvant bevacizumab (p = 0.014). Karnofsky performance status (KPS) and age were not significantly different between treatment groups. Treatment-related Grade 3/4 toxicity for patients receiving and not receiving adjuvant BVZ was 10% and 14%, respectively (p = 0.58).On multivariate analysis, the relative risk of death and progression with adjuvant bevacizumab was 0.37 (confidence interval [CI] 0.17-0.82) and 0.45 (CI 0.21-0.97). KPS >70 and age <50 years were significantly associated with improved survival. Conclusions: The combination of salvage radiosurgery and bevacizumab to treat recurrent malignant

  9. Delayed Complications in Patients Surviving at Least 3 Years After Stereotactic Radiosurgery for Brain Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Masaaki, E-mail: BCD06275@nifty.com [Katsuta Hospital Mito GammaHouse, Hitachi-naka (Japan); Department of Neurosurgery, Tokyo Women' s Medical University Medical Center East, Tokyo (Japan); Kawabe, Takuya [Katsuta Hospital Mito GammaHouse, Hitachi-naka (Japan); Department of Neurosurgery, Kyoto Prefectural University of Medicine Graduate School of Medical Sciences, Kyoto (Japan); Higuchi, Yoshinori [Department of Neurosurgery, Chiba University Graduate School of Medicine, Chiba (Japan); Sato, Yasunori [Clinical Research Center, Chiba University Graduate School of Medicine, Chiba (Japan); Nariai, Tadashi [Department of Neurosurgery, Graduate School, Tokyo Medical and Dental University School of Medicine, Tokyo (Japan); Barfod, Bierta E. [Katsuta Hospital Mito GammaHouse, Hitachi-naka (Japan); Kasuya, Hidetoshi [Department of Neurosurgery, Tokyo Women' s Medical University Medical Center East, Tokyo (Japan); Urakawa, Yoichi [Katsuta Hospital Mito GammaHouse, Hitachi-naka (Japan)

    2013-01-01

    Purpose: Little is known about delayed complications after stereotactic radiosurgery in long-surviving patients with brain metastases. We studied the actual incidence and predictors of delayed complications. Patients and Methods: This was an institutional review board-approved, retrospective cohort study that used our database. Among our consecutive series of 2000 patients with brain metastases who underwent Gamma Knife radiosurgery (GKRS) from 1991-2008, 167 patients (8.4%, 89 women, 78 men, mean age 62 years [range, 19-88 years]) who survived at least 3 years after GKRS were studied. Results: Among the 167 patients, 17 (10.2%, 18 lesions) experienced delayed complications (mass lesions with or without cyst in 8, cyst alone in 8, edema in 2) occurring 24.0-121.0 months (median, 57.5 months) after GKRS. The actuarial incidences of delayed complications estimated by competing risk analysis were 4.2% and 21.2% at the 60th month and 120th month, respectively, after GKRS. Among various pre-GKRS clinical factors, univariate analysis demonstrated tumor volume-related factors: largest tumor volume (hazard ratio [HR], 1.091; 95% confidence interval [CI], 1.018-1.154; P=.0174) and tumor volume {<=}10 cc vs >10 cc (HR, 4.343; 95% CI, 1.444-12.14; P=.0108) to be the only significant predictors of delayed complications. Univariate analysis revealed no correlations between delayed complications and radiosurgical parameters (ie, radiosurgical doses, conformity and gradient indexes, and brain volumes receiving >5 Gy and >12 Gy). After GKRS, an area of prolonged enhancement at the irradiated lesion was shown to be a possible risk factor for the development of delayed complications (HR, 8.751; 95% CI, 1.785-157.9; P=.0037). Neurosurgical interventions were performed in 13 patients (14 lesions) and mass removal for 6 lesions and Ommaya reservoir placement for the other 8. The results were favorable. Conclusions: Long-term follow-up is crucial for patients with brain metastases

  10. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery.

    Science.gov (United States)

    Han, Eun Young; Zhang, Xin; Yan, Yulong; Sharma, Sunil; Penagaricano, Jose; Moros, Eduardo; Corry, Peter

    2012-01-01

    At the University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

  11. Preliminary experience of fractionated stereotactic radiosurgery with extend system of Gamma Knife

    Directory of Open Access Journals (Sweden)

    Raj Bisht

    2016-03-01

    Full Text Available Purpose: The purpose of this study is to present multisession stereotactic radiosurgery with initial experience using custom made extend system (ES of Gamma Knife.Methods: The ES is comprised of a carbon fiber frame also called extend frame, vacuum head rest cushion, patient surveillance unit and a configurable front piece with dental impression tray. The extend frame is a rigid connection between patient's head and patient positioning system (PPS of Gamma Knife. A dental impression of patient was created and attached to the frontal piece of extend system. The treatment setup involves positioning the patient within the extend frame using patient specific headrest cushion and front piece. The reference patient’s head position was recorded through measurements of repositioning check tool (RCT apertures using a high precision digital probe before computed tomography (CT scan. The RCT measurements taken before treatment were compared with recorded reference position to ensure appropriate patient treatment position. Volumetric magnetic resonance (MR scan was co-registered with stereotactic CT scan on Leksell Gamma plan. Fused MR to CT images on Gamma Plan was utilized to delineate regions of interest and prepare a precise treatment plan. The presented study includes positional reproducibility check and dosimetric evaluation of ten patients treated with ES.Results: Forty-three fractions on ten patients with prescribed treatment format were delivered successfully. An average tumor volume of 11.26 cm3 (range, 340 mm3 to 59.12 cm3 was treated with ES. The mean tumor coverage of 91.91% (range, 90% to 95% was able to achieve at 50% prescription isodose without compromising adjacent normal structure radiation dose tolerances. The mean inter-fraction positional variation of 0.69 mm influences an inherent strength of immobilization technique. Follow-up of seven patients at a median interval of 16 months (range, 9 months to 26 months showed evidence of 100

  12. Effect of dosimeter type for commissioning small photon beams on calculated dose distribution in stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    García-Garduño, O. A., E-mail: oagarciag@innn.edu.mx, E-mail: amanda.garcia.g@gmail.com [Laboratorio de Física Médica, Instituto Nacional de Neurología y Neurocirugía, Mexico City 14269, México and Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, Legaria 694, México City 11500, México (Mexico); Rodríguez-Ponce, M. [Departamento de Biofísica, Instituto Nacional de Cancerología, Mexico City 14080, México (Mexico); Gamboa-deBuen, I. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico City 04510 (Mexico); Rodríguez-Villafuerte, M. [Instituto de Física, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico City 04510 (Mexico); Galván de la Cruz, O. O. [Laboratorio de Física Médica, Instituto Nacional de Neurología y Neurocirugía, Mexico City 14269, México (Mexico); and others

    2014-09-15

    Purpose: To assess the impact of the detector used to commission small photon beams on the calculated dose distribution in stereotactic radiosurgery (SRS). Methods: In this study, six types of detectors were used to characterize small photon beams: three diodes [a silicon stereotactic field diode SFD, a silicon diode SRS, and a silicon diode E], an ionization chamber CC01, and two types of radiochromic film models EBT and EBT2. These detectors were used to characterize circular collimated beams that were generated by a Novalis linear accelerator. This study was conducted in two parts. First, the following dosimetric data, which are of particular interest in SRS, were compared for the different detectors: the total scatter factor (TSF), the tissue phantom ratios (TPRs), and the off-axis ratios (OARs). Second, the commissioned data sets were incorporated into the treatment planning system (TPS) to compare the calculated dose distributions and the dose volume histograms (DVHs) that were obtained using the different detectors. Results: The TSFs data measured by all of the detectors were in good agreement with each other within the respective statistical uncertainties: two exceptions, where the data were systematically below those obtained for the other detectors, were the CC01 results for all of the circular collimators and the EBT2 film results for circular collimators with diameters below 10.0 mm. The OAR results obtained for all of the detectors were in excellent agreement for all of the circular collimators. This observation was supported by the gamma-index test. The largest difference in the TPR data was found for the 4.0 mm circular collimator, followed by the 10.0 and 20.0 mm circular collimators. The results for the calculated dose distributions showed that all of the detectors passed the gamma-index test at 100% for the 3 mm/3% criteria. The aforementioned observation was true regardless of the size of the calculation grid for all of the circular collimators

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

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, Alvin R. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Cuneo, Kyle C. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Desjardins, Annick [Department of Surgery, Duke University, Durham, North Carolina (United States); Sampson, John H. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Surgery, Duke University, Durham, North Carolina (United States); McSherry, Frances; Herndon, James E. [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina (United States); Peters, Katherine B. [Department of Surgery, Duke University, Durham, North Carolina (United States); Allen, Karen [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Hoang, Jenny K. [Department of Radiology, Duke University, Durham, North Carolina (United States); Chang, Zheng; Craciunescu, Oana [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Vredenburgh, James J.; Friedman, Henry S. [Department of Surgery, Duke University, Durham, North Carolina (United States); Kirkpatrick, John P., E-mail: john.kirkpatrick@dm.duke.edu [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Surgery, Duke University, Durham, North Carolina (United States)

    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.

  14. Long-Term Outcomes of Stereotactic Radiosurgery for Treatment of Cavernous Sinus Meningiomas

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    Santos, Marcos Antonio dos, E-mail: marcosrxt@gmail.com [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Bustos Perez de Salcedo, Jose; Gutierrez Diaz, Jose Angel [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Neurosurgery Department, Sanatorio San Francisco de Asis, Madrid (Spain); Calvo, Felipe A. [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Department of Oncology, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Samblas, Jose [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Neurosurgery Department, Sanatorio San Francisco de Asis, Madrid (Spain); Marsiglia, Hugo [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Sallabanda, Kita [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Neurosurgery Department, Sanatorio San Francisco de Asis, Madrid (Spain)

    2011-12-01

    Purpose: Patients with cavernous sinus meningiomas (CSM) have an elevated risk of surgical morbidity and mortality. Recurrence is often observed after partial resection. Stereotactic radiosurgery (SRS), either alone or combined with surgery, represents an important advance in CSM management, but long-term results are lacking. Methods and Materials: A total of 88 CSM patients, treated from January 1991 to December 2005, were retrospectively reviewed. The mean follow-up was 86.8 months (range, 17.1-179.4 months). Among the patients, 22 were followed for more than 10 years. There was a female predominance (84.1%). The age varied from 16 to 90 years (mean, 51.6). In all, 47 patients (53.4%) received SRS alone, and 41 patients (46.6%) had undergone surgery before SRS. A dose of 14 Gy was prescribed to isodose curves from 50% to 90%. In 25 patients (28.4%), as a result of the proximity to organs at risk, the prescribed dose did not completely cover the target. Results: After SRS, 65 (73.8%) patients presented with tumor volume reduction; 14 (15.9%) remained stable, and 9 (10.2%) had tumor progression. The progression-free survival was 92.5% at 5 years, and 82.5% at 10 years. Age, sex, maximal diameter of the treated tumor, previous surgery, and complete target coverage did not show significant associations with prognosis. Among the 88 treated patients, 17 experienced morbidity that was related to SRS, and 6 of these patients spontaneously recovered. Conclusions: SRS is an effective and safe treatment for CSM, feasible either in the primary or the postsurgical setting. Incomplete coverage of the target did not worsen outcomes. More than 80% of the patients remained free of disease progression during long-term follow-up.

  15. Hematological Toxicity After Robotic Stereotactic Body Radiosurgery for Treatment of Metastatic Gynecologic Malignancies

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    Kunos, Charles A., E-mail: charles.kunos@UHhospitals.org [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, Ohio (United States); Debernardo, Robert [Department of Obstetrics and Gynecology, University Hospitals Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, Ohio (United States); Radivoyevitch, Tomas [Department of Epidemiology and Biostatistics, University Hospitals Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, Ohio (United States); Fabien, Jeffrey; Dobbins, Donald C.; Zhang Yuxia; Brindle, James [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, Ohio (United States)

    2012-09-01

    Purpose: To evaluate hematological toxicity after robotic stereotactic body radiosurgery (SBRT) for treatment of women with metastatic abdominopelvic gynecologic malignancies. Methods and Materials: A total of 61 women with stage IV gynecologic malignancies treated with abdominopelvic SBRT were analyzed after ablative radiation (2400 cGy/3 divided consecutive daily doses) delivered by a robotic-armed Cyberknife SBRT system. Abdominopelvic bone marrow was identified using computed tomography-guided contouring. Fatigue and hematologic toxicities were graded by retrospective assignment of common toxicity criteria for adverse events (version 4.0). Bone marrow volume receiving 1000 cGy (V10) was tested for association with post-therapy (median 32 days [25%-75% quartile, 28-45 days]) white- or red-cell counts, hemoglobin levels, and platelet counts as marrow toxicity surrogates. Results: In all, 61 women undergoing abdominopelvic SBRT had a median bone marrow V10 of 2% (25%-75% quartile: 0%-8%). Fifty-seven (93%) of 61 women had received at least 1 pre-SBRT marrow-taxing chemotherapy regimen for metastatic disease. Bone marrow V10 did not associate with hematological adverse events. In all, 15 grade 2 (25%) and 2 grade 3 (3%) fatigue symptoms were self-reported among the 61 women within the first 10 days post-therapy, with fatigue resolved spontaneously in all 17 women by 30 days post-therapy. Neutropenia was not observed. Three (5%) women had a grade 1 drop in hemoglobin level to <10.0 g/dL. Single grade 1, 2, and 3 thrombocytopenias were documented in 3 women. Conclusions: Abdominopelvic SBRT provided ablative radiation dose to cancer targets without increased bone marrow toxicity. Abdominopelvic SBRT for metastatic gynecologic malignancies warrants further study.

  16. Robotic real-time translational and rotational head motion correction during frameless stereotactic radiosurgery

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    Liu, Xinmin; Belcher, Andrew H.; Grelewicz, Zachary; Wiersma, Rodney D., E-mail: rwiersma@uchicago.edu [Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, Illinois 60637 (United States)

    2015-06-15

    Purpose: To develop a control system to correct both translational and rotational head motion deviations in real-time during frameless stereotactic radiosurgery (SRS). Methods: A novel feedback control with a feed-forward algorithm was utilized to correct for the coupling of translation and rotation present in serial kinematic robotic systems. Input parameters for the algorithm include the real-time 6DOF target position, the frame pitch pivot point to target distance constant, and the translational and angular Linac beam off (gating) tolerance constants for patient safety. Testing of the algorithm was done using a 4D (XY Z + pitch) robotic stage, an infrared head position sensing unit and a control computer. The measured head position signal was processed and a resulting command was sent to the interface of a four-axis motor controller, through which four stepper motors were driven to perform motion compensation. Results: The control of the translation of a brain target was decoupled with the control of the rotation. For a phantom study, the corrected position was within a translational displacement of 0.35 mm and a pitch displacement of 0.15° 100% of the time. For a volunteer study, the corrected position was within displacements of 0.4 mm and 0.2° over 98.5% of the time, while it was 10.7% without correction. Conclusions: The authors report a control design approach for both translational and rotational head motion correction. The experiments demonstrated that control performance of the 4D robotic stage meets the submillimeter and subdegree accuracy required by SRS.

  17. Leptomeningeal disease following stereotactic radiosurgery for brain metastases from breast cancer.

    Science.gov (United States)

    Trifiletti, Daniel M; Romano, Kara D; Xu, Zhiyuan; Reardon, Kelli A; Sheehan, Jason

    2015-09-01

    Leptomeningeal disease (LMD) is a highly aggressive and usually rapidly fatal condition. The purpose of this study is to identify clinical factors that can serve to predict for LMD at the time of stereotactic radiosurgery (SRS) for brain metastases from breast carcinoma. We conducted a retrospective review of patients with brain metastases from breast cancer treated with SRS from 1995 to 2014 at our institution. Clinical, radiographic, and dosimetric data were collected. LMD was diagnosed by cerebrospinal fluid (CSF) cytology or MRI demonstrating CSF seeding. Comparative statistical analyses were conducted using Cox proportional hazards regression, binary logistic regression, and/or log-rank test. 126 patients met inclusion criteria. Eighteen patients (14 %) developed LMD following SRS. From the time of SRS, the actuarial rate of LMD at 12 months from diagnosis of brain metastasis was 9 % (11 patients). Active disease in the chest at the time of SRS was associated with development of LMD (p = 0.038). Factors including receptor status, tumor size, number of intra-axial tumors, cystic tumor morphology, prior WBRT, active bone metastases, and active liver metastases were not significantly associated with the development of LMD. In patients with brain metastasis from breast cancer that undergo SRS, there is a relatively low rate of LMD. We found that while tumor hormonal status, bone metastases, and hepatic metastases were not associated with the development of LMD, active lung metastases at SRS was associated with LMD. Further research may help to delineate a causative relationship between metastatic lung disease and LMD.

  18. Micromultileaf collimator-based stereotactic radiosurgery for selected arteriovenous malformations: Technique and preliminary experience

    Directory of Open Access Journals (Sweden)

    Jalali Rakesh

    2009-01-01

    Full Text Available Purpose : To report our experience of stereotactic radiosurgery (SRS in consecutively treated patients with arteriovenous malformations (AVMs. Materials and Methods : Of the 87 patients, 23 patients qualified and were treated with SRS as per predefined protocol according to AVM size, location, neurological status, prior bleeding, and the AVM score. All had Spletzer-Martin grade II/III and AVM scores < 2.5. Patients underwent SRS using micromultileaf collimators delivering multiple noncoplanar fixed fields. Doses were prescribed using the Flickinger model. Patients were followed up with magnetic resonance angiography (MRA and digitally subtracted angiography (DSA. Results : The mean nidus volume was 3.65 cc. The mean prescribed maximum dose was 22 Gy and the marginal dose was 19.24 Gy; 12 Gy normal brain volume was 8.39 cc and 12 Gy marginal volume was 5.03 cc. Mean dose to brain stem, pituitary hypothalamic axis, and optic chiasm was 2.5, 0.72, and 0.49 Gy, respectively. At a median follow-up of 22 months (range 1.5-71.2 months, 7 of 10 patients presenting with a neurological deficit showed significant improvement. All 15 patients who underwent MRA 1.5-2 years after SRS had no residual nidus yielding an MRA complete obliteration rate of 100%. Twelve patients also underwent a check DSA, which confirmed obliteration in 11 of them resulting in an accuracy of MRA of 92%. One patient after SRS had transient deterioration of motor power, which resolved completely after a short course of steroids and another had mild worsening of the hemiparesis. All patients are able to lead an active functional life. Conclusions : Careful selection of cases suitable for SRS provides optimum obliteration rates with low toxicity.

  19. Dosimetric comparison of Helical Tomotherapy and Gamma Knife Stereotactic Radiosurgery for single brain metastasis

    Directory of Open Access Journals (Sweden)

    Linskey Mark E

    2006-08-01

    Full Text Available Abstract Background Helical Tomotherapy (HT integrates linear accelerator and computerized tomography (CT technology to deliver IMRT. Targets are localized (i.e. outlined as gross tumor volume [GTV] and planning target volume [PTV] on the planning kVCT study while daily MVCT is used for correction of patient's set-up and assessment of inter-fraction anatomy changes. Based on dosimetric comparisons, this study aims to find dosimetric equivalency between single fraction HT and Gamma Knife® stereotactic radiosurgery (GKSRS for the treatment of single brain metastasis. Methods The targeting MRI data set from the GKSRS were used for tomotherapy planning. Five patients with single brain metastasis treated with GKSRS were re-planned in the HT planning station using the same prescribed doses. There was no expansion of the GTV to create the PTV. Sub-volumes were created within the PTV and prescribed to the maximum dose seen in the GKSRS plans to imitate the hot spot normally seen in GKSRS. The PTV objective was set as a region at risk in HT planning using the same prescribed dose to the PTV periphery as seen in the corresponding GKSRS plan. The tumor volumes ranged from 437–1840 mm3. Results Conformality indices are inconsistent between HT and GKSRS. HT generally shows larger lower isodose line volumes, has longer treatment time than GKSRS and can treat a much larger lesion than GKSRS. Both HT and GKSRS single fraction dose-volume toxicity may be prohibitive in treating single or multiple lesions depending on the number and the sizes of the lesions. Conclusion Based on the trend for larger lower dose volumes and more constricted higher dose volumes in HT as compared to GKSRS, dosimetric equivalency was not reached between HT and GKSRS.

  20. Long-term results of LINAC-based stereotactic radiosurgery for acoustic neuroma: The Greek experience

    Directory of Open Access Journals (Sweden)

    Kalogeridi Maria-Aggeliki

    2009-01-01

    Full Text Available Purpose: To estimate the value of LINAC-based stereotactic radiosurgery (SRS for the long-term local control of unilateral acoustic neuromas. Materials and Methods: Twenty patients (median age 66; range 57-80 years with unilateral acoustic neuroma underwent LINAC-based SRS from May 2000 through June 2004 with a dose of 11-12 Gy. The follow-up period ranged from 36 to 84 months (median follow-up period: 55 months. Before SRS none of the patients had useful hearing. The follow-up consisted of repeat imaging studies and clinical examination for assessment of facial and trigeminal nerve function at 6-month intervals for the first year and yearly thereafter. Results: Eleven tumors (58% decreased in size and eight (42% remained stable. One tumor showed a minor increase in size on the MRI done 6 months after SRS in comparison with the pretreatment MRI; however, a subsequent decrease was noticed on the next radiographic assessment and the tumor remained stable from then on. None of the tumors increased in size in the long-term follow-up, thus giving an overall growth control of 100% for the patients in this study. None of the patients had useful hearing before SRS, so hearing level was not assessed during follow-up. No patient developed new, permanent facial or trigeminal neuropathy. Conclusion: LINAC-based SRS with 11-12 Gy provides excellent tumor control in acoustic neuroma and has low toxicity even after long-term follow-up.

  1. Radiosurgery indicators and fractionated stereotactic in tumors of central nervous system; Indicacoes de radiocirurgia e estereotaxia fracionada nos tumores de sistema nervoso central

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    Grabarz, Daniel; Hattori, Rodrigo Rodrigues [Centro Oncologico, Mogi das Cruzes, SP (Brazil)

    2009-11-15

    This article shows stereotactic radiosurgery, that consists of non-invasive therapeutic modality that uses the administration of a high dose of external radiation with extreme precision and targets well-located and well-defined limits, which are traditionally intracranial.

  2. Stereotactic Hypofractionated Radiation Therapy as a Bridge to Transplantation for Hepatocellular Carcinoma: Clinical Outcome and Pathologic Correlation

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    Katz, Alan W., E-mail: alan_katz@urmc.rochester.edu [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Chawla, Sheema [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Qu, Zhenhong [Anatomic Pathology, William Beaumont Hospital, Royal Oak, Michigan (United States); Kashyap, Randeep [Department of Solid Organ Transplant, University of Rochester Medical Center, Rochester, New York (United States); Milano, Michael T. [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Hezel, Aram F. [Department of Medicine, Division of Hematology and Oncology, University of Rochester Medical Center, Rochester, New York (United States)

    2012-07-01

    Purpose: We sought to determine efficacy, safety, and outcome of stereotactic hypofractionated radiation therapy (SHORT) as a suitable bridging therapy for patients awaiting liver transplantation (LT) for hepatocellular carcinoma (HCC). We also examined histological response to radiation in the resected or explanted livers. Methods and Materials: Between August 2007 and January 2009, 18 patients with 21 lesions received SHORT. A median total dose of 50 Gy was delivered in 10 fractions. Three patients underwent either chemoembolization (n = 1) or radiofrequency ablation (n = 2) prior to SHORT. Radiographic response was based on computed tomography evaluation at 3 months after SHORT. Histological response as a percentage of tumor necrosis was assessed by a quantitative morphometric method. Results: Six of 18 patients were delisted because of progression (n = 3) or other causes (n = 3). Twelve patients successfully underwent major hepatic resection (n = 1) or LT (n = 11) at a median follow-up of 6.3 months (range, 0.6-11.6 months) after completion of SHORT. No patient developed gastrointestinal toxicity Grade {>=}3 or radiation-induced liver disease. Ten patients with 11 lesions were evaluable for pathological response. Two lesions had 100% necrosis, three lesions had {>=}50% necrosis, four lesions had {<=}50% necrosis, and two lesions had no necrosis. All patients were alive after LT and/or major hepatic resection at a median follow-up of 19.6 months. Conclusions: SHORT is an effective bridging therapy for patients awaiting LT for HCC. It provides excellent in-field control with minimal side effects, helps to downsize or stabilize tumors prior to LT, and achieves good pathological response.

  3. Patterns of Failure After Concurrent Bevacizumab and Hypofractionated Stereotactic Radiation Therapy for Recurrent High-Grade Glioma

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    Shapiro, Lauren Q. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Beal, Kathryn, E-mail: bealk@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Goenka, Anuj [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Karimi, Sasan [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Iwamoto, Fabio M. [Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Zhang, Zhigang [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Lassman, Andrew B.; Abrey, Lauren E. [Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Gutin, Philip H. [Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2013-03-01

    Purpose: Concurrent bevacizumab with hypofractionated stereotactic radiation therapy (HSRT) is safe and effective for the treatment of recurrent high-grade gliomas (HGG). The objective of this study was to characterize the patterns of failure after this treatment regimen. Methods and Materials: Twenty-four patients with recurrent enhancing HGG were previously treated on an institutional review board-approved protocol of concurrent bevacizumab and reirradiation. Patients received 30 Gy in 5 fractions to the recurrent tumor with HSRT. Brain magnetic resonance imaging (MRI) was performed every 2 cycles, and bevacizumab was continued until clinical or radiographic tumor progression according to the criteria of Macdonald et al. MRI at the time of progression was fused to the HSRT treatment plan, and the location of recurrence was classified on the basis of volume within the 95% isodose line. Outcomes based on patient characteristics, tumor grade, recurrence pattern, and best response to treatment were analyzed by the Kaplan-Meier method. Results: Twenty-two patients experienced either clinical or radiographic progression. Recurrent tumor was enhancing in 15 (71.4%) and nonenhancing in 6 (28.6%) patients. Eleven patients (52.4%) had recurrence within the radiation field, 5 patients (23.8%) had marginal recurrence, and 5 patients had recurrence outside the radiation field. Pattern of enhancement and location of failure did not correlate with overall survival or progression-free survival. Radiographic response was the only variable to significantly correlate with progression-free survival. Conclusions: Despite the promising initial response seen with the addition of HSRT to bevacizumab as salvage treatment for recurrent HGG, approximately half of patients ultimately still experience failure within the radiation field. The rate of local failure with the addition of HSRT seems to be lower than that seen with bevacizumab alone in the salvage setting. Our data underscore the

  4. MO-D-BRB-07: Failure-Mode and Effects Analysis Study for CyberKnife Stereotactic Radiosurgery.

    Science.gov (United States)

    Dieterich, S; Ford, E; Halasz, C

    2012-06-01

    The purpose of this study is to conduct a Failure Modes and Effect Analysis (FMEA) for CyberKnife Stereotactic Radiosurgery to determine the sensitivity of existing QA procedures and determine in which areas new QA procedures needed to be implemented. Members from each professional team providing service for CyberKnife radiosurgery (Medical Physicists, Nurses, Physicians, Radiation Therapists, and Administrators) were interviewed to gather potential failure modes. A patient flow chart was developed from patient consult to conclusion of last treatment. Failure modes were mapped to nodes in the flow charts to identify potential high-risk areas. A matrix was created to correlate existing QA procedures with failure modes to identify failure modes that were not covered by any QA as well as identify the sensitivity of QA procedures to prevent failures. 180 failure modes were identified. Current AAPM QA recommendations were found to focus preferentially on technical failure modes (15%), while the majority of failure modes found are process failures and human errors (85%). Creating a Venn diagram of CyberKnife and Gamma Knife failure modes revealed a large overlap area. The most effective QA checks are checklists for physics second chart review and pre- treatment time-out checklists. Existing checklists were modified and new checklists added to address high-ranked failure modes. New procedure guidelines, e.g. for contouring workflow and add-on simulations, were developed as QC to address clusters of failure modes. An ARIA-CyberKnife DICOM interface is being implemented to resolve failure modes centering around multiple fraction, multiple plan treatments and total dose tracking. This work is the first FMEA study for the CyberKnife stereotactic radiosurgery. It will facilitate medical physicists using the CyberKnife to deliver SRS/SBRT treatments to transition from experience-based technical QA to a comprehensive new quality paradigm including technical, process, and human

  5. Is there room for stereotactic radiosurgery as an option for third ventricular colloid cysts in patients refusing surgery? A case report and some therapeutic considerations

    Directory of Open Access Journals (Sweden)

    Leonardo Lustgarten

    2015-01-01

    Full Text Available Background : Colloid cysts of the third ventricle are epithelium-lined mucus-filled cysts usually occurring in the anterosuperior third ventricle. They are benign, slow-growing lesions but with the risk of sudden death. Treatment alternatives for symptomatic cysts include stereotactic aspiration, microsurgical or endoscopic approaches, and shunts for hydrocephalus. Case Description: The current case describes a patient presenting with hydrocephalus and a colloid cyst. A ventriculoperitoneal shunt was placed as the patient refused a definitive surgical procedure for the removal of the cyst, and stereotactic radiosurgery was then performed. Conclusions: Stereotactic radiosurgery may be a reasonable alternative with minimal risks in those patients harboring a third ventricle colloid cyst refusing a definitive surgical procedure for resection of the cyst.

  6. Knowledge-based prediction of plan quality metrics in intracranial stereotactic radiosurgery.

    Science.gov (United States)

    Shiraishi, Satomi; Tan, Jun; Olsen, Lindsey A; Moore, Kevin L

    2015-02-01

    The objective of this work was to develop a comprehensive knowledge-based methodology for predicting achievable dose-volume histograms (DVHs) and highly precise DVH-based quality metrics (QMs) in stereotactic radiosurgery/radiotherapy (SRS/SRT) plans. Accurate QM estimation can identify suboptimal treatment plans and provide target optimization objectives to standardize and improve treatment planning. Correlating observed dose as it relates to the geometric relationship of organs-at-risk (OARs) to planning target volumes (PTVs) yields mathematical models to predict achievable DVHs. In SRS, DVH-based QMs such as brain V10Gy (volume receiving 10 Gy or more), gradient measure (GM), and conformity index (CI) are used to evaluate plan quality. This study encompasses 223 linear accelerator-based SRS/SRT treatment plans (SRS plans) using volumetric-modulated arc therapy (VMAT), representing 95% of the institution's VMAT radiosurgery load from the past four and a half years. Unfiltered models that use all available plans for the model training were built for each category with a stratification scheme based on target and OAR characteristics determined emergently through initial modeling process. Model predictive accuracy is measured by the mean and standard deviation of the difference between clinical and predicted QMs, δQM = QMclin - QMpred, and a coefficient of determination, R(2). For categories with a large number of plans, refined models are constructed by automatic elimination of suspected suboptimal plans from the training set. Using the refined model as a presumed achievable standard, potentially suboptimal plans are identified. Predictions of QM improvement are validated via standardized replanning of 20 suspected suboptimal plans based on dosimetric predictions. The significance of the QM improvement is evaluated using the Wilcoxon signed rank test. The most accurate predictions are obtained when plans are stratified based on proximity to OARs and their PTV

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

    Energy Technology Data Exchange (ETDEWEB)

    Moussazadeh, Nelson [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, New York (United States); Lis, Eric [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Katsoulakis, Evangelia [Department of Radiation Oncology, New York Methodist Hospital, Brooklyn, New York (United States); Kahn, Sweena; Svoboda, Marek; DiStefano, Natalie M.; McLaughlin, Lily [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Bilsky, Mark H. [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, New York (United States); Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Laufer, Ilya, E-mail: lauferi@mskcc.org [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, New York (United States)

    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

  8. A Phase 2 Trial of Stereotactic Radiosurgery Boost After Surgical Resection for Brain Metastases

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    Brennan, Cameron [Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Yang, T. Jonathan [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Hilden, Patrick; Zhang, Zhigang [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Chan, Kelvin; Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Chan, Timothy A. [Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Lymberis, Stella C. [Department of Radiation Oncology, New York University Langone Medical Center, New York, New York (United States); Narayana, Ashwatha [Department of Radiation Oncology, Greenwich Hospital, Greenwich, Connecticut (United States); Tabar, Viviane; Gutin, Philip H. [Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ballangrud, Åse [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Lis, Eric [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Beal, Kathryn, E-mail: BealK@MSKCC.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2014-01-01

    Purpose: To evaluate local control after surgical resection and postoperative stereotactic radiosurgery (SRS) for brain metastases. Methods and Materials: A total of 49 patients (50 lesions) were enrolled and available for analysis. Eligibility criteria included histologically confirmed malignancy with 1 or 2 intraparenchymal brain metastases, age ≥18 years, and Karnofsky performance status (KPS) ≥70. A Cox proportional hazard regression model was used to test for significant associations between clinical factors and overall survival (OS). Competing risks regression models, as well as cumulative incidence functions, were fit using the method of Fine and Gray to assess the association between clinical factors and both local failure (LF; recurrence within surgical cavity or SRS target), and regional failure (RF; intracranial metastasis outside of treated volume). Results: The median follow-up was 12.0 months (range, 1.0-94.1 months). After surgical resection, 39 patients with 40 lesions were treated a median of 31 days (range, 7-56 days) later with SRS to the surgical bed to a median dose of 1800 cGy (range, 1500-2200 cGy). Of the 50 lesions, 15 (30%) demonstrated LF after surgery. The cumulative LF and RF rates were 22% and 44% at 12 months. Patients who went on to receive SRS had a significantly lower incidence of LF (P=.008). Other factors associated with improved local control include non-small cell lung cancer histology (P=.048), tumor diameter <3 cm (P=.010), and deep parenchymal tumors (P=.036). Large tumors (≥3 cm) with superficial dural/pial involvement showed the highest risk for LF (53.3% at 12 months). Large superficial lesions treated with SRS had a 54.5% LF. Infratentorial lesions were associated with a higher risk of developing RF compared to supratentorial lesions (P<.001). Conclusions: Postoperative SRS is associated with high rates of local control, especially for deep brain metastases <3 cm. Tumors ≥3 cm with superficial dural

  9. TU-G-BRD-04: A Round Robin Dosimetry Intercomparison of Gamma Stereotactic Radiosurgery Calibration Protocols

    Energy Technology Data Exchange (ETDEWEB)

    Drzymala, R [Washington University, Saint Louis, MO (United States); Alvarez, P [University of Texas MD Anderson Cancer Center, Houston, TX (United States); Bednarz, G [University of Pittsburgh Medical Center, Pittsburgh, PA (United States); Bourland, J [Wake Forest University, Winston-salem, NC (United States); DeWerd, L [University of Wisconsin, Madison/ADCL, Madison, WI (United States); Ma, L [University of California San Francisco Comprehensive Cancer Center, San Francisco, CA (United States); Meltsner, S [Duke University Medical Center, Durham, NC (United States); Neyman, G [The Cleveland Clinic Foundation, Beachwood, OH (United States); Novotny, J [Hospital Na Homolce, Prague (Czech Republic); Petti, P [Washington Hospital, Fremont, CA (United States); Rivard, M [Tufts University School of Medicine, Boston, MA (United States); Shiu, A [University of Southern California, Los Angeles, CA (United States); Goetsch, S [Dade Moeller Health Group, La Jolla, CA (United States)

    2015-06-15

    Purpose: The purpose of this multi-institutional study was to compare two new gamma stereotactic radiosurgery (GSRS) dosimetry protocols to existing calibration methods. The ultimate goal was to guide AAPM Task Group 178 in recommending a standard GSRS dosimetry protocol. Methods: Nine centers (ten GSRS units) participated in the study. Each institution made eight sets of dose rate measurements: six with two different ionization chambers in three different 160mm-diameter spherical phantoms (ABS plastic, Solid Water and liquid water), and two using the same ionization chambers with a custom in-air positioning jig. Absolute dose rates were calculated using a newly proposed formalism by the IAEA working group for small and non-standard radiation fields and with a new air-kerma based protocol. The new IAEA protocol requires an in-water ionization chamber calibration and uses previously reported Monte-Carlo generated factors to account for the material composition of the phantom, the type of ionization chamber, and the unique GSRS beam configuration. Results obtained with the new dose calibration protocols were compared to dose rates determined by the AAPM TG-21 and TG-51 protocols, with TG-21 considered as the standard. Results: Averaged over all institutions, ionization chambers and phantoms, the mean dose rate determined with the new IAEA protocol relative to that determined with TG-21 in the ABS phantom was 1.000 with a standard deviation of 0.008. For TG-51, the average ratio was 0.991 with a standard deviation of 0.013, and for the new in-air formalism it was 1.008 with a standard deviation of 0.012. Conclusion: Average results with both of the new protocols agreed with TG-21 to within one standard deviation. TG-51, which does not take into account the unique GSRS beam configuration or phantom material, was not expected to perform as well as the new protocols. The new IAEA protocol showed remarkably good agreement with TG-21. Conflict of Interests: Paula Petti

  10. SU-E-CAMPUS-T-01: Automation of the Winston-Lutz Test for Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Litzenberg, D; Irrer, J; Kessler, M; Lam, K [University of Michigan, Ann Arbor, MI (United States); Keranen, W [Varian Medical Systems, Inc., Palo Alto, CA (United States)

    2014-06-15

    Purpose: To optimize clinical efficiency and shorten patient wait time by minimizing the time and effort required to perform the Winston-Lutz test before stereotactic radiosurgery (SRS) through automation of the delivery, analysis, and documentation of results. Methods: The radiation fields of the Winston-Lutz (WL) test were created in a “machine-QA patient” saved in ARIA for use before SRS cases. Images of the BRW target ball placed at mechanical isocenter are captured with the portal imager for each of four, 2cm×2cm, MLC-shaped beams. When the WL plan is delivered and closed, this event is detected by in-house software called EventNet which automates subsequent processes with the aid of the ARIA web services. Images are automatically retrieved from the ARIA database and analyzed to determine the offset of the target ball from radiation isocenter. The results are posted to a website and a composite summary image of the results is pushed back into ImageBrowser for review and authenticated documentation. Results: The total time to perform the test was reduced from 20-25 minutes to less than 4 minutes. The results were found to be more accurate and consistent than the previous method which used radiochromic film. The images were also analyzed with DoseLab for comparison. The difference between the film and automated WL results in the X and Y direction and the radius were (−0.17 +/− 0.28) mm, (0.21 +/− 0.20) mm and (−0.14 +/− 0.27) mm, respectively. The difference between the DoseLab and automated WL results were (−0.05 +/− 0.06) mm, (−0.01 +/− 0.02) mm and (0.01 +/− 0.07) mm, respectively. Conclusions: This process reduced patient wait times by 15–20 minutes making the treatment machine available to treat another patient. Accuracy and consistency of results were improved over the previous method and were comparable to other commercial solutions. Access to the ARIA web services is made possible through an Eclipse co-development agreement

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

    Energy Technology Data Exchange (ETDEWEB)

    Hattangadi-Gluth, Jona A. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, California (United States); Chapman, Paul H. [Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts (United States); Kim, Daniel; Niemierko, Andrzej; Bussière, Marc R.; Stringham, Alison; Daartz, Juliane [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Ogilvy, Christopher [Department of Neurosurgery, Beth Israel Deaconess Medical Center, Boston, Massachusetts (United States); Loeffler, Jay S. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Shih, Helen A., E-mail: hshih@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    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

  12. SU-E-T-94: An Advanced Rotating Gamma Ray System for Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C; Chibani, O; Li, J; Chen, L [Fox Chase Cancer Center, Philadelphia, PA (United States); Mora, G [Universidade de Lisboa, Codex, Lisboa (Portugal)

    2015-06-15

    Purpose: Co-60 beams have unique dosimetric properties that are ideally suited for cranial treatments. Co-60 sources with cone-shaped collimators provide conformal dose distributions allowing for ablative treatments with rapid dose falloff to spare nearby critical structures. This work investigates a novel, image-guided, rotational Gamma ray system that provides both superior dose conformity/gradient and accurate stereotaxy for stereotactic radiosurgery (SRS). Methods: The SupeRay system (Cyber Medical Corp., China) consists of a rotating source chamber containing 30 gamma sources focusing at the isocenter with 4 collimators measuring 3, 4, 8 and 16mm in diameter. A novel switch design enables the 30 Gamma sources to be turned off at any arbitrarily selected 60° interval in order to avoid critical structures. The 3D treatment couch provides automatic treatment positioning between individual shots and the kV imaging system provides orthogonal images with a spatial resolution of 0.24mm to facilitate target localization. Monte Carlo simulations were used to compute dose distributions and compare with measurements and other Gamma ray SRS systems. Results: Monte Carlo results confirmed the SupeRay design parameters including output factors and 3D dose distributions. Its beam penumbra/dose gradient is similar to or slightly better than that of the Elekta Gamma Knife. The penumbra in the (x,y,z) direction was (7.38mm,7.38mm,3.86mm) for the 16mm collimator, (4.83mm,4.83mm,3.12mm) for the 8mm collimator, and (3.03mm,3.03mm,2.38mm) for the 4mm collimator, respectively, on the SupeRay system while it was (9.5mm,10.0mm,2.9mm), (4.3mm,4.3mm,2.9mm) and (3.2mm,3.2mm,1.9mm) for the same collimator sizes, respectively, on the Perfexion system. The kV imaging system together with a non-invasive relocatable frame provides accurate target localization (<0.5mm) for cases requiring multiple treatment fractions. Conclusion: Because of the unique dosimetric properties of Co-60 sources

  13. Dosimetric comparison of helical tomotherapy and dynamic conformal arc therapy in stereotactic radiosurgery for vestibular schwannomas.

    Science.gov (United States)

    Lee, Tsair-Fwu; Chao, Pei-Ju; Wang, Chang-Yu; Lan, Jen-Hong; Huang, Yu-Je; Hsu, Hsuan-Chih; Sung, Chieh-Cheng; Su, Te-Jen; Lian, Shi-Long; Fang, Fu-Min

    2011-01-01

    The dosimetric results of stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) performed using dynamic conformal arc therapy (DCAT) with the Novalis system and helical TomoTherapy (HT) were compared using plan quality indices. The HT plans were created for 10 consecutive patients with VS previously treated with SRS using the Novalis system. The dosimetric indices used to compare the techniques included the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV), the comprehensive quality index (CQI) for nine organs at risk (OARs), gradient score index (GSI) for the dose drop-off outside the PTV, and plan quality index (PQI), which was verified using the plan quality discerning power (PQDP) to incorporate 3 plan indices, to evaluate the rival plans. The PTV ranged from 0.27-19.99 cm(3) (median 3.39 cm(3)), with minimum required PTV prescribed doses of 10-16 Gy (median 12 Gy). Both systems satisfied the minimum required PTV prescription doses. HT conformed better to the PTV (CI: 1.51 ± 0.23 vs. 1.94 ± 0.34; p < 0.01), but had a worse drop-off outside the PTV (GSI: 40.3 ± 10.9 vs. 64.9 ± 13.6; p < 0.01) compared with DCAT. No significant difference in PTV homogeneity was observed (HI: 1.08 ± 0.03 vs. 1.09 ± 0.02; p = 0.20). HT had a significantly lower maximum dose in 4 OARs and significant lower mean dose in 1 OAR; by contrast, DCAT had a significantly lower maximum dose in 1 OAR and significant lower mean dose in 2 OARs, with the CQI of the 9 OARs = 0.92 ± 0.45. Plan analysis using PQI (HT 0.37 ± 0.12 vs. DCAT 0.65 ± 0.08; p < 0.01), and verified using the PQDP, confirmed the dosimetric advantage of HT. However, the HT system had a longer beam-on time (33.2 ± 7.4 vs. 4.6 ± 0.9 min; p < 0.01) and consumed more monitor units (16772 ± 3803 vs. 1776 ± 356.3; p < 0.01). HT had a better dose conformity and similar dose homogeneity but worse dose gradient than DCAT. Plan analysis confirmed the dosimetric advantage of HT

  14. Investigation of dosimetric differences between the TMR 10 and convolution algorithm for Gamma Knife stereotactic radiosurgery.

    Science.gov (United States)

    Rojas-Villabona, Alvaro; Kitchen, Neil; Paddick, Ian

    2016-11-01

    Since its inception, doses applied using Gamma Knife Radiosurgery (GKR) have been calculated using a simple TMR algorithm, which assumes the patient's head is of even density, the same as water. This results in a significant approximation of the dose delivered by the Gamma Knife. We investigated how GKR dose calculations varied when using a new convolution algorithm clinically available for GKR planning that takes into account density variations in the head compared with the established calculation algorithm. Fifty-five patients undergoing GKR and harboring 85 lesions were voluntarily and prospectively enrolled into the study. Their clinical treatment plans were created and delivered using TMR 10, but were then recalculated using the density correction algorithm. Dosimetric differences between the planning algorithms were noted. Beam on time (BOT), which is directly proportional to dose, was the main value investigated. Changes of mean and maximum dose to organs at risk (OAR) were also assessed. Phantom studies were performed to investigate the effect of frame and pin materials on dose calculation using the convolution algorithm. Convolution yielded a mean increase in BOT of 7.4% (3.6%-11.6%). However, approximately 1.5% of this amount was due to the head contour being derived from the CT scans, as opposed to measurements using the Skull Scaling Instrument with TMR. Dose to the cochlea calculated with the convolution algorithm was approximately 7% lower than with the TMR 10 algorithm. No significant difference in relative dose distribution was noted and CT artifact typically caused by the stereotactic frame, glue embolization material or different fixation pin materials did not systematically affect convolution isodoses. Nonetheless, substantial error was introduced to the convolution calculation in one target located exactly in the area of major CT artifact caused by a fixation pin. Inhomogeneity correction using the convolution algorithm results in a considerable

  15. Stereotactic Radiosurgery for Trigeminal Neuralgia Improves Patient-Reported Quality of Life and Reduces Depression.

    Science.gov (United States)

    Kotecha, Rupesh; Miller, Jacob A; Modugula, Sujith; Barnett, Gene H; Murphy, Erin S; Reddy, Chandana A; Suh, John H; Neyman, Gennady; Machado, Andre; Nagel, Sean; Chao, Samuel T

    2017-08-01

    To characterize quality-of-life (QOL) outcomes after stereotactic radiosurgery (SRS) for trigeminal neuralgia (TN). The EuroQOL 5 Dimensions (EQ-5D) and Patient Health Questionnaire 9 (PHQ-9) were prospectively collected before and after SRS for 50 patients with TN. Pain response and treatment-related facial numbness were classified by Barrow Neurological Institute (BNI) scales. Differences in pooled QOL outcomes were tested with paired t tests and sign tests. The Kaplan-Meier method was used to estimate time-dependent improvements in the EQ-5D index, EQ-5D perceived health status (PHS), PHQ-9 score, and freedom from pain failure (BNI class IV-V) or facial numbness (BNI class III-IV). Following SRS, the 12-month rate of freedom from pain failure was 92% (95% confidence interval [CI], 77%-97%) while the 12-month rate of freedom from facial numbness was 89% (95% CI, 66%-97%). Significant improvements in the EQ-5D index (P<.01), PHS (P=.01), and PHQ-9 (P=.03) were observed, driven by the EQ-5D subscores for self-care and for pain and/or discomfort (P=.02 and P<.01, respectively). At 12 months after SRS, the actuarial rates of improvement in the EQ-5D, PHS, and PHQ-9 were 55% (95% CI, 40%-70%), 59% (95% CI, 40%-76%), and 59% (95% CI, 39%-76%), respectively. The median time to improvement in each of the QOL measures was 9 months (95% CI, 3-36 months) for the EQ-5D index, 5 months (95% CI, 3-36 months) for PHS, and 9 months (95% CI, 3-18 months) for the PHQ-9. On multivariate analysis, only higher prescription dose (86 Gy vs ≤82 Gy) was associated with improvement in the EQ-5D index (hazard ratio, 5.73; 95% CI, 1.85-22.33; P<.01). Patients with TN treated with SRS reported significant improvements in multiple QOL measures, with the therapeutic benefit strongly driven by improvements in pain and/or discomfort and in self-care, along with lower rates of depression. In this analysis, there appears to be a correlation between prescription dose and treatment

  16. Image guided respiratory gated hypofractionated Stereotactic Body Radiation Therapy (H-SBRT) for liver and lung tumors: Initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Wurm, R.E.; Gum, F.; Erbel, S. [Charite Campus Mitte, Berlin (Germany). Dept. of Radiation Oncology

    2006-09-15

    To evaluate our initial experience with image guided respiratory gated H-SBRT for liver and lung tumors. The system combines a stereoscopic x-ray imaging system (ExacTrac{sup R} X-Ray 6D) with a dedicated conformal stereotactic radiosurgery and radiotherapy linear accelerator (Novalis) and ExacTrac{sup R} Adaptive Gating for dynamic adaptive treatment. Moving targets are located and tracked by x-ray imaging of implanted fiducial markers defined in the treatment planning computed tomography (CT). The marker position is compared with the position in verification stereoscopic x-ray images, using fully automated marker detection software. The required shift for a correct, gated set-up is calculated and automatically applied. We present our acceptance testing and initial experience in patients with liver and lung tumors. For treatment planning CT and Fluorodeoxyglucose-Positron Emission Tomography (FDG-PET) as well as magnetic resonance imaging (MRI) taken at free breathing and expiration breath hold with internal and external fiducials present were used. Patients were treated with 8-11 consecutive fractions to a dose of 74.8-79.2 Gy. Phantom tests demonstrated targeting accuracy with a moving target to within {+-}1 mm. Inter- and intrafractional patient set-up displacements, as corrected by the gated set-up and not detectable by a conventional set-up, were up to 30 mm. Verification imaging to determine target location during treatment showed an average marker position deviation from the expected position of up to 4 mm on real patients. This initial evaluation shows the accuracy of the system and feasibility of image guided real-time respiratory gated H-SBRT for liver and lung tumors.

  17. Stereotactic radiosurgery for treatment of brain metastases. A report of the DEGRO Working Group on Stereotactic Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kocher, Martin [University Hospital Cologne, Department of Radiation Oncology, Koeln (Germany); Wittig, Andrea [Philips-University Marburg, Department of Radiotherapy and Radiation Oncology, Marburg (Germany); Piroth, Marc Dieter [University Hospital RWTH Aachen, Department of Radiotherapy and Radiation Oncology, Aachen (Germany); Helios-Klinikum Wuppertal, Klinik fuer Strahlentherapie und Radio-Onkologie, Wuppertal (Germany); Treuer, Harald; Ruge, Maximilian [University Hospital Cologne, Department of Stereotaxy and Functional Neurosurgery, Koeln (Germany); Seegenschmiedt, Heinrich [Strahlenzentrum Hamburg, Radioonkologie und Strahlentherapie, Hamburg (Germany); Grosu, Anca-Ligia [University Hospital Freiburg, Department of Radiation Oncology, Freiburg (Germany); Guckenberger, Matthias [University of Wuerzburg, Department of Radiation Oncology, Wuerzburg (Germany); University Hospital Zurich, Department of Radiation Oncology, Zuerich (Switzerland)

    2014-06-15

    This report from the Working Group on Stereotaktische Radiotherapie of the German Society of Radiation Oncology (Deutsche Gesellschaft fuer Radioonkologie, DEGRO) provides recommendations for the use of stereotactic radiosurgery (SRS) on patients with brain metastases. It considers existing international guidelines and details them where appropriate. The main recommendations are: Patients with solid tumors except germ cell tumors and small-cell lung cancer with a life expectancy of more than 3 months suffering from a single brain metastasis of less than 3 cm in diameter should be considered for SRS. Especially when metastases are not amenable to surgery, are located in the brain stem, and have no mass effect, SRS should be offered to the patient. For multiple (two to four) metastases - all less than 2.5 cm in diameter - in patients with a life expectancy of more than 3 months, SRS should be used rather than whole-brain radiotherapy (WBRT). Adjuvant WBRT after SRS for both single and multiple (two to four) metastases increases local control and reduces the frequency of distant brain metastases, but does not prolong survival when compared with SRS and salvage treatment. As WBRT carries the risk of inducing neurocognitive damage, it seems reasonable to withhold WBRT for as long as possible. A single (marginal) dose of 20 Gy is a reasonable choice that balances the effect on the treated lesion (local control, partial remission) against the risk of late side effects (radionecrosis). Higher doses (22-25 Gy) may be used for smaller (< 1 cm) lesions, while a dose reduction to 18 Gy may be necessary for lesions greater than 2.5-3 cm. As the infiltration zone of the brain metastases is usually small, the GTV-CTV (gross tumor volume-clinical target volume) margin should be in the range of 0-1 mm. The CTV-PTV (planning target volume) margin depends on the treatment technique and should lie in the range of 0-2 mm. Distant brain recurrences fulfilling the aforementioned criteria

  18. Hypofractionated stereotactic body radiotherapy in low- and intermediate-risk prostate carcinoma

    Science.gov (United States)

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

    2016-01-01

    Purpose Stereotactic body radiotherapy (SBRT) takes advantage of low α/β ratio of prostate cancer to deliver a large dose in few fractions. We examined clinical outcomes of SBRT using CyberKnife for the treatment of low- and intermediate-risk prostate cancer. Materials and Methods This study was based on a retrospective analysis of the 33 patients treated with SBRT using CyberKnife for localized prostate cancer (27.3% in low-risk and 72.7% in intermediate-risk). Total dose of 36.25 Gy in 5 fractions of 7.25 Gy were administered. The acute and late toxicities were recorded using the Radiation Therapy Oncology Group scale. Prostate-specific antigen (PSA) response was monitored. Results Thirty-three patients with a median 51 months (range, 6 to 71 months) follow-up were analyzed. There was no biochemical failure. Median PSA nadir was 0.27 ng/mL at median 33 months and PSA bounce occurred in 30.3% (n = 10) of patients at median at median 10.5 months after SBRT. No grade 3 acute toxicity was noted. The 18.2% of the patients had acute grade 2 genitourinary (GU) toxicities and 21.2% had acute grade 2 gastrointestinal (GI) toxicities. After follow-up of 2 months, most complications had returned to baseline. There was no grade 3 late GU and GI toxicity. Conclusion Our experience with SBRT using CyberKnife in low- and intermediate-risk prostate cancer demonstrates favorable efficacy and toxicity. Further studies with more patients and longer follow-up duration are required. PMID:27306777

  19. Hypofractionated stereotactic body radiotherapy in low- and intermediate-risk prostate carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hun Jung; Phak, Jeong Hoon; Kim, Woo Chul [Dept. of Radiation Oncology, Inha University Hospital, Inha University School of Medicine, Incheon (Korea, Republic of)

    2016-12-15

    Stereotactic body radiotherapy (SBRT) takes advantage of low α/β ratio of prostate cancer to deliver a large dose in few fractions. We examined clinical outcomes of SBRT using CyberKnife for the treatment of low- and intermediate-risk prostate cancer. This study was based on a retrospective analysis of the 33 patients treated with SBRT using CyberKnife for localized prostate cancer (27.3% in low-risk and 72.7% in intermediate-risk). Total dose of 36.25 Gy in 5 fractions of 7.25 Gy were administered. The acute and late toxicities were recorded using the Radiation Therapy Oncology Group scale. Prostate-specific antigen (PSA) response was monitored. Thirty-three patients with a median 51 months (range, 6 to 71 months) follow-up were analyzed. There was no biochemical failure. Median PSA nadir was 0.27 ng/mL at median 33 months and PSA bounce occurred in 30.3% (n = 10) of patients at median at median 10.5 months after SBRT. No grade 3 acute toxicity was noted. The 18.2% of the patients had acute grade 2 genitourinary (GU) toxicities and 21.2% had acute grade 2 gastrointestinal (GI) toxicities. After follow-up of 2 months, most complications had returned to baseline. There was no grade 3 late GU and GI toxicity. Our experience with SBRT using CyberKnife in low- and intermediate-risk prostate cancer demonstrates favorable efficacy and toxicity. Further studies with more patients and longer follow-up duration are required.

  20. A concise review of the efficacy of stereotactic radiosurgery in the management of melanoma and renal cell carcinoma brain metastases

    Directory of Open Access Journals (Sweden)

    Hanson Peter W

    2012-08-01

    Full Text Available Abstract Melanoma and renal cell carcinoma have a well-documented tendency to develop metastases to the brain. Treating these lesions has traditionally been problematic, because chemotherapy has difficulty crossing the blood brain barrier and whole brain radiation therapy (WBRT is a relatively ineffective treatment against these radioresistant tumor histologies. In recent years, stereotactic radiosurgery (SRS has emerged as an effective and minimally-invasive treatment modality for irradiating either single or multiple intracranial structures in one clinical treatment setting. For this reason, we conducted a review of modern literature analyzing the efficacy of SRS in the management of patients with melanoma and renal cell carcinoma brain metastases. In our analysis we found SRS to be a safe, effective and attractive treatment modality for managing radioresistant brain metastases and highlighted the need for randomized trials comparing WBRT alone vs. SRS alone vs. WBRT plus SRS in treating patients with radioresistant brain metastases.

  1. A kinetic model of tumor growth and its radiation response with an application to Gamma Knife stereotactic radiosurgery

    CERN Document Server

    Watanabe, Yoichi; Leder, Kevin Z; Hui, Susanta K

    2015-01-01

    We developed a mathematical model to simulate the growth of tumor volume and its response to a single fraction of high dose irradiation. We made several key assumptions of the model. Tumor volume is composed of proliferating (or dividing) cancer cells and non-dividing (or dead) cells. Tumor growth rate (or tumor volume doubling time, Td) is proportional to the ratio of the volumes of tumor vasculature and the tumor. The vascular volume grows slower than the tumor by introducing the vascular growth retardation factor, theta. Upon irradiation the proliferating cells gradually die over a fixed time period after irradiation. Dead cells are cleared away with cell clearance time, Tcl. The model was applied to simulate pre-treatment growth and post-treatment radiation response of rat rhabdomyosarcoma tumor and metastatic brain tumors of five patients who were treated by Gamma Knife stereotactic radiosurgery (GKSRS). By selecting appropriate model parameters, we showed the temporal variation of the tumors for both th...

  2. Radical stereotactic radiosurgery with real-time tumor motion tracking in the treatment of small peripheral lung tumors

    Directory of Open Access Journals (Sweden)

    Chang Thomas

    2007-10-01

    Full Text Available Abstract Background Recent developments in radiotherapeutic technology have resulted in a new approach to treating patients with localized lung cancer. We report preliminary clinical outcomes using stereotactic radiosurgery with real-time tumor motion tracking to treat small peripheral lung tumors. Methods Eligible patients were treated over a 24-month period and followed for a minimum of 6 months. Fiducials (3–5 were placed in or near tumors under CT-guidance. Non-isocentric treatment plans with 5-mm margins were generated. Patients received 45–60 Gy in 3 equal fractions delivered in less than 2 weeks. CT imaging and routine pulmonary function tests were completed at 3, 6, 12, 18, 24 and 30 months. Results Twenty-four consecutive patients were treated, 15 with stage I lung cancer and 9 with single lung metastases. Pneumothorax was a complication of fiducial placement in 7 patients, requiring tube thoracostomy in 4. All patients completed radiation treatment with minimal discomfort, few acute side effects and no procedure-related mortalities. Following treatment transient chest wall discomfort, typically lasting several weeks, developed in 7 of 11 patients with lesions within 5 mm of the pleura. Grade III pneumonitis was seen in 2 patients, one with prior conventional thoracic irradiation and the other treated with concurrent Gefitinib. A small statistically significant decline in the mean % predicted DLCO was observed at 6 and 12 months. All tumors responded to treatment at 3 months and local failure was seen in only 2 single metastases. There have been no regional lymph node recurrences. At a median follow-up of 12 months, the crude survival rate is 83%, with 3 deaths due to co-morbidities and 1 secondary to metastatic disease. Conclusion Radical stereotactic radiosurgery with real-time tumor motion tracking is a promising well-tolerated treatment option for small peripheral lung tumors.

  3. Esophageal Dose Tolerance to Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors for Late Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Stephans, Kevin L., E-mail: stephak@ccf.org [Department of Radiation Oncology, Cleveland Clinic, Taussig Cancer Center, Cleveland, Ohio (United States); Djemil, Toufik [Department of Radiation Oncology, Cleveland Clinic, Taussig Cancer Center, Cleveland, Ohio (United States); Diaconu, Claudiu [Cleveland Clinic Learner College of Medicine, Cleveland, Ohio (United States); Reddy, Chandana A.; Xia, Ping; Woody, Neil M.; Greskovich, John [Department of Radiation Oncology, Cleveland Clinic, Taussig Cancer Center, Cleveland, Ohio (United States); Makkar, Vinit [Department of Medical Oncology, Cleveland Clinic, Taussig Cancer Center, Cleveland, Ohio (United States); Videtic, Gregory M.M. [Department of Radiation Oncology, Cleveland Clinic, Taussig Cancer Center, Cleveland, Ohio (United States)

    2014-09-01

    Purpose: To identify factors associated with grade ≥3 treatment related late esophageal toxicity after lung or liver stereotactic body radiation therapy (SBRT). Methods and Materials: This was a retrospective review of 52 patients with a planning target volume within 2 cm of the esophagus from a prospective registry of 607 lung and liver SBRT patients treated between 2005 and 2011. Patients were treated using a risk-adapted dose regimen to a median dose of 50 Gy in 5 fractions (range, 37.5-60 Gy in 3-10 fractions). Normal structures were contoured using Radiation Therapy Oncology Group (RTOG) defined criteria. Results: The median esophageal point dose and 1-cc dose were 32.3 Gy (range, 8.9-55.4 Gy) and 24.0 Gy (range, 7.8-50.9 Gy), respectively. Two patients had an esophageal fistula at a median of 8.4 months after SBRT, with maximum esophageal point doses of 51.5 and 52 Gy, and 1-cc doses of 48.1 and 50 Gy, respectively. These point and 1-cc doses were exceeded by 9 and 2 patients, respectively, without a fistula. The risk of a fistula for point doses exceeding 40, 45, and 50 Gy was 9.5% (n=2/21), 10.5% (n=2/19), and 12.5% (n=2/16), respectively. The risk of fistula for 1-cc doses exceeding 40, 45, and 50 Gy was 25% (n=2/9), 50% (n=2/4), and 50% (n=2/4), respectively. Eighteen patients received systemic therapy after SBRT (11 systemic chemotherapy, and 6 biologic agents, and 1 both). Both patients with fistulas had received adjuvant anti-angiogenic (vascular endothelial growth factor) agents within 2 months of completing SBRT. No patient had a fistula in the absence of adjuvant VEGF-modulating agents. Conclusions: Esophageal fistula is a rare complication of SBRT. In this series, fistula was seen with esophageal point doses exceeding 51 Gy and 1-cc doses greater than 48 Gy. Notably, however, fistula was seen only in those patients who also received adjuvant VEGF-modulating agents after SBRT. The potential interaction of dose and adjuvant therapy

  4. Repeat stereotactic radiosurgery in the management of brain metastases from NSCLC: A case report and review of the literature.

    Science.gov (United States)

    Marvaso, Giulia; Barone, Agnese; Vaccaro, Caterina; Bruzzaniti, Vicente; Grespi, Silvia; Scotti, Valerio; Bianco, Cataldo

    2013-10-01

    The aims of radiotherapeutic treatment of brain metastases include maintaining neurocognitive function and improvement of survival. Based on these premises, we present a case report in which the role of repeat stereotactic radiosurgery (SRS) was investigated in a patient with a recurrent brain metastasis from non-small cell lung cancer in the same area as previously treated with radiosurgery. A 40-year-old male caucasian patient was diagnosed with brain metastasis from non-small cell lung cancer (NSCLC) and underwent SRS. The patient developed a recurrence of the disease and a second SRS on the same area was performed. After 8 months, tumor restaging demonstrated a lesion compatible with a recurrence and the patient underwent surgery. Histological diagnosis following surgery revealed only the occurrence of radionecrosis. Radiotherapy was well-tolerated and no grade 3/4 neurological toxicity occurred. To date, no consensus exists on the efficacy of retreatment with SRS. Despite the limited number of studies in this field, in the present case report, we outline the outcomes of this unconventional approach.

  5. Stereotactic radiosurgery for intradural spine tumors using cone-beam CT image guidance.

    Science.gov (United States)

    Monserrate, Andrés; Zussman, Benjamin; Ozpinar, Alp; Niranjan, Ajay; Flickinger, John C; Gerszten, Peter C

    2017-01-01

    OBJECTIVE Cone-beam CT (CBCT) image guidance technology has been widely adopted for spine radiosurgery delivery. There is relatively little experience with spine radiosurgery for intradural tumors using CBCT image guidance. This study prospectively evaluated a series of intradural spine tumors treated with radiosurgery. Patient setup accuracy for spine radiosurgery delivery using CBCT image guidance for intradural spine tumors was determined. METHODS Eighty-two patients with intradural tumors were treated and prospectively evaluated. The positioning deviations of the spine radiosurgery treatments in patients were recorded. Radiosurgery was delivered using a linear accelerator with a beam modulator and CBCT image guidance combined with a robotic couch that allows positioning correction in 3 translational and 3 rotational directions. To measure patient movement, 3 quality assurance CBCTs were performed and recorded in 30 patients: before, halfway, and after the radiosurgery treatment. The positioning data and fused images of planning CT and CBCT from the treatments were analyzed to determine intrafraction patient movements. From each of 3 CBCTs, 3 translational and 3 rotational coordinates were obtained. RESULTS The radiosurgery procedure was successfully completed for all patients. Lesion locations included cervical (22), thoracic (17), lumbar (38), and sacral (5). Tumor histologies included schwannoma (27), neurofibromas (18), meningioma (16), hemangioblastoma (8), and ependymoma (5). The mean prescription dose was 17 Gy (range 12-27 Gy) delivered in 1-3 fractions. At the halfway point of the radiation, the translational variations and standard deviations were 0.4 ± 0.5, 0.5 ± 0.8, and 0.4 ± 0.5 mm in the lateral (x), longitudinal (y), and anteroposterior (z) directions, respectively. Similarly, the variations immediately after treatment were 0.5 ± 0.4, 0.5 ± 0.6, and 0.6 ± 0.5 mm along x, y, and z directions, respectively. The mean rotational angles were 0

  6. Stereotactic radiosurgery for newly diagnosed brain metastases. Comparison of three dose levels

    Energy Technology Data Exchange (ETDEWEB)

    Rades, Dirk [University of Luebeck, Department of Radiation Oncology, Luebeck (Germany); Hornung, Dagmar [University Medical Center Hamburg-Eppendorf, Department of Radiation Oncology, Hamburg (Germany); Blanck, Oliver [University of Luebeck, Department of Radiation Oncology, Luebeck (Germany); CyberKnife Center Northern Germany, Guestrow (Germany); Martens, Kristina [University of Luebeck, Department of Radiation Oncology, Luebeck (Germany); University of Luebeck, Center for Integrative Psychiatry, Luebeck (Germany); Khoa, Mai Trong [Hanoi Medical University, Department of Nuclear Medicine, Hanoi (Viet Nam); Bach Mai Hospital, Nuclear Medicine and Oncology Center, Hanoi (Viet Nam); Trang, Ngo Thuy [Bach Mai Hospital, Nuclear Medicine and Oncology Center, Hanoi (Viet Nam); Hueppe, Michael [University of Luebeck, Department of Anesthesiology, Luebeck (Germany); Terheyden, Patrick [University of Luebeck, Department of Dermatology, Luebeck (Germany); Gliemroth, Jan [University of Luebeck, Department of Neurosurgery, Luebeck (Germany); Schild, Steven E. [Mayo Clinic Scottsdale, Department of Radiation Oncology, Scottsdale (United States)

    2014-09-15

    Three doses were compared for local control of irradiated metastases, freedom from new brain metastases, and survival in patients receiving stereotactic radiosurgery (SRS) alone for one to three newly diagnosed brain metastases. In all, 134 patients were assigned to three groups according to the SRS dose given to the margins of the lesions: 13-16 Gy (n = 33), 18 Gy (n = 18), and 20 Gy (n = 83). Additional potential prognostic factors were evaluated: age (≤ 60 vs. > 60 years), gender, Karnofsky Performance Scale score (70-80 vs. 90-100), tumor type (non-small-cell lung cancer vs. melanoma vs. others), number of brain metastases (1 vs. 2-3), lesion size (< 15 vs. ≥ 15 mm), extracranial metastases (no vs. yes), RPA class (1 vs. 2), and interval of cancer diagnosis to SRS (≤ 24 vs. > 24 months). For 13-16 Gy, 18 Gy, and 20 Gy, the 1-year local control rates were 31, 65, and 79 %, respectively (p < 0.001). The SRS dose maintained significance on multivariate analysis (risk ratio: 2.25; 95 % confidence interval: 1.56-3.29; p < 0.001). On intergroup comparisons of local control, 20 Gy was superior to 13-16 Gy (p < 0.001) but not to 18 Gy (p = 0.12); 18 Gy showed a strong trend toward better local control when compared with 13-16 Gy (p = 0.059). Freedom from new brain metastases (p = 0.57) and survival (p = 0.15) were not associated with SRS dose in the univariate analysis. SRS doses of 18 Gy and 20 Gy resulted in better local control than 13-16 Gy. However, 20 Gy and 18 Gy must be compared again in a larger cohort of patients. Freedom from new brain metastases and survival were not associated with SRS dose. (orig.) [German] Drei Dosislevel bei der alleinigen stereotaktischen Radiochirurgie (SRS) von 1 bis 3 neu diagnostizierten Hirnmetastasen wurden hinsichtlich lokaler Kontrolle der bestrahlten Metastasen, Nichtauftreten neuer Hirnmetastasen und Gesamtueberleben verglichen. Nach der am Rand der Metastasen applizierten SRS-Dosis wurden 134 Patienten den Gruppen 13

  7. Dosimetry of cone-defined stereotactic radiosurgery fields with a commercial synthetic diamond detector

    Energy Technology Data Exchange (ETDEWEB)

    Morales, Johnny E., E-mail: johnny.morales@lh.org.au [Department of Radiation Oncology, Chris O’Brien Lifehouse, 119-143 Missenden Road, Camperdown, NSW 2050, Australia and School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Level 4 O Block, Garden’s Point, Brisbane, QLD 4001 (Australia); Crowe, Scott B.; Trapp, J. V. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Level 4 O Block, Garden’s Point, Brisbane, QLD 4001 (Australia); Hill, Robin [Department of Radiation Oncology, Chris O’Brien Lifehouse, 119-143 Missenden Road, Camperdown, NSW 2050 (Australia); Freeman, Nigel [Department of Radiation Oncology, St Vincent’s Hospital, Victoria Street, Darlinghurst, NSW 2010 (Australia)

    2014-11-01

    Purpose: Small field x-ray beam dosimetry is difficult due to lack of lateral electronic equilibrium, source occlusion, high dose gradients, and detector volume averaging. Currently, there is no single definitive detector recommended for small field dosimetry. The objective of this work was to evaluate the performance of a new commercial synthetic diamond detector, namely, the PTW 60019 microDiamond, for the dosimetry of small x-ray fields as used in stereotactic radiosurgery (SRS). Methods: Small field sizes were defined by BrainLAB circular cones (4–30 mm diameter) on a Novalis Trilogy linear accelerator and using the 6 MV SRS x-ray beam mode for all measurements. Percentage depth doses (PDDs) were measured and compared to an IBA SFD and a PTW 60012 E diode. Cross profiles were measured and compared to an IBA SFD diode. Field factors, Ω{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r}}}}}}}}}, were calculated by Monte Carlo methods using BEAMnrc and correction factors, k{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r}}}}}}}}}, were derived for the PTW 60019 microDiamond detector. Results: For the small fields of 4–30 mm diameter, there were dose differences in the PDDs of up to 1.5% when compared to an IBA SFD and PTW 60012 E diode detector. For the cross profile measurements the penumbra values varied, depending upon the orientation of the detector. The field factors, Ω{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r}}}}}}}}}, were calculated for these field diameters at a depth of 1.4 cm in water and they were within 2.7% of published values for a similar linear accelerator. The corrections factors, k{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r}}}}}}}}}, were derived for the PTW 60019 microDiamond detector. Conclusions

  8. SU-E-T-438: Frameless Cranial Stereotactic Radiosurgery Immobilization Effectiveness Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, T; Green, S; Sheu, R; Lo, Y [Mount Sinai Medical Center, New York, NY (United States)

    2015-06-15

    Purpose: To evaluate immobilization effectiveness of Brainlab frameless mask in cranial stereotactic radiosurgery (SRS). Methods: Two sets of setup images were collected pre-and post-treatment for 24 frameless SRS cases. The pre-treatment images were obtained after applying 2D-2D kV image-guided shifts with patients in treatment position and approved by physicians; the post-treatment images were taken immediately after treatment completion. All cases were treated on a Novalis linac with ExacTrac positioning system and Exact Couch. The two image sets were compared with the correctional shifts measured by ExacTrac 6D auto-fusion. The shift differences were considered patient motion within the frameless mask and were used to evaluate its effectiveness for immobilization. Two-tailed paired t-test was applied for significance comparison. Results: The correctional shifts (mean±STD, median) of pre-and post-treatment images were 0.33±0.27mm, 0.26mm and 0.34±0.27mm, 0.23mm (p=0.740) in lateral direction; 0.32±0.29mm, 0.22mm and 0.48±0.30mm, 0.50mm (p=0.012) in longitudinal direction; 0.31±0.22mm, 0.24mm and 0.33±0.21mm, 0.36mm (p=0.623) in vertical direction. The radial correctional shifts (mean±STD, median) of pre -and post-treatment images were 0.60±0.38mm, 0.45mm and 0.75±0.31mm, 0.66mm (p=0.033). The shift differences (mean±STD, median, maximum) were 0.35±0.28mm, 0.3mm, 1.05mm, 0.34±0.28mm, 0.3mm, 1.00mm, 0.24±0.15mm, 0.21mm, 0.60mm and 0.61±0.32mm, 0.57mm, 1.40mm in lateral, longitudinal, vertical and radial direction, respectively. Two shifts greater than 1 mm (1.06mm and 1.02mm) were acquired from post-treatment images. However, the shift differences were only 0.09 and 0.19mm for these two shifts. Two patients with shift differences greater than 1mm (1.05 and 1.04mm) were observed and didn’t coincide with those two who had post-correctional shifts greater than 1mm. Conclusion: Image-guided SRS allowed us to set up patients with sub

  9. Viability of an isocentric cobalt-60 teletherapy unit for stereotactic radiosurgery.

    Science.gov (United States)

    Poffenbarger, B A; Podgorsak, E B

    1998-10-01

    The potential for radiosurgery with an isocentric teletherapy cobalt unit was evaluated in three areas: (1) the physical properties of radiosurgical beams, (2) the quality of radiosurgical dose distributions obtained with four to ten noncoplanar converging arcs, and (3) the accuracy with which the radiosurgical dose can be delivered. In each of these areas the cobalt unit provides a viable alternative to an isocentric linear accelerator (linac) as a radiation source for radiosurgery. A 10 MV x-ray beam from a linac used for radiosurgery served as a standard for comparison. The difference between the 80%-20% penumbras of stationary radiosurgical fields in the nominal diameter range from 10 to 40 mm of the cobalt-60 and 10 MV photon beams is remarkably small, with the cobalt-60 beam penumbras, on average, only about 0.7 mm larger than those of the linac beam. Differences between the cobalt-60 and 10 MV radiosurgical treatment plans in terms of dose homogeneity within the target volume, conformity of the prescribed isodose volume to the target volume, and dose falloffs outside the target volume are also minimal, and therefore of essentially no clinical significance. Moreover, measured isodose distributions for a radiosurgical procedure on our Theratron T-780 cobalt unit agreed with calculated distributions to within the +/- 1 mm spatial and +/- 5% numerical dose tolerances, which are generally specified for radiosurgery. The viability of isocentric cobalt units for radiosurgery will be of particular interest to centers in developing countries where cobalt units, because of their relatively low costs, provide the only megavoltage source of radiation for radiotherapy, and could easily and inexpensively be modified for radiosurgery. Of course, the quality assurance protocols and mechanical condition of a particular teletherapy cobalt unit must meet stringent requirements before the use of the unit for radiosurgery can be advocated.

  10. 357 Gamma Knife Stereotactic Radiosurgery in the Management of Large Cerebral Arteriovenous Malformations.

    Science.gov (United States)

    Singh, Manmohan; Aggarwal, Deepak; Kale, Shashank Sharad

    2016-08-01

    Large brain arteriovenous malformations (AVMs) pose management challenge in neurosurgical practice. Management remains conservative unless these AVMs bleed or present with neurological deficits. For patients who require treatment, options are limited with very high treatment-related morbidity. Gamma knife radiosurgery remains an excellent noninvasive option for such AVMs. This is a retrospective study of 74 patients with large AVMs who were treated with gamma knife radiosurgery over 16 years. Sixty-five patients were treated with single-fraction and 9 patients were treated with volume-staged gamma knife radiosurgery. Average follow-up was 4.2 years. In the single-fraction group, 90% patients had SM grade 3 and 4 AVMs while 10% patients had SM grade 5 AVMs. Mean marginal radiation dose was 23.66 Gy. Overall obliteration rate of 66% was observed. Four percent of patients rebled in this group. Postradiation edema was observed in 18% of patient who presented with headache, new-onset seizures, and motor deficits. The symptoms improved with steroid therapy in most patients. Delayed cyst formations were seen in 2 patients. Interestingly, 41% patients showed seizure control after gamma knife radiosurgery. In volume-staging group, 60% patients had SM grade 4 AVMs and 40% patients has SM grade 5 AVMs. All patients were treated in 2 sittings. Average marginal dose used was 23 Gy. These patients showed nearly 80% reduction in the nidus volume at follow-up. No new-onset deficit was observed in this group, and all patients tolerated the treatment very well. Large-volume AVMs can be managed with gamma knife radiosurgery with acceptable risks. Single-fraction gamma knife radiosurgery should be considered for moderate-size AVMs away from critical structures. Large-volume lesions should be treated with volume-staged gamma knife radiosurgery.

  11. Physical aspects of dynamic stereotactic radiosurgery with very small photon beams (1.5 and 3 mm in diameter).

    Science.gov (United States)

    Paskalev, Kamen A; Seuntjens, Jan P; Patrocinio, Horacio J; Podgorsak, Ervin B

    2003-02-01

    Stereotactic radiosurgery is often used for treating functional disorders. For some of these disorders, the size of the target can be on the order of a millimeter and the radiation dose required for treatment on the order of 80 Gy. The very small radiation field and high prescribed dose present a difficult challenge in beam calibration, dose distribution calculation, and dose delivery. In this work the dose distribution for dynamic stereotactic radiosurgery, carried out with 1.5 and 3 mm circular fields, was studied. A 10 MV beam from a Clinac-18 linac (Varian, Palo Alto, CA) was used as the radiation source. The BEAM/EGS4 Monte Carlo code was used to model the treatment head of the machine along with the small-field collimators. The models were validated with the EGSnrc code, first through a calculation of percent depth doses (PDD) and dose profiles in a water phantom for the two small stationary circular beams and then through a comparison of the calculated with measured PDD and profile data. The three-dimensional (3-D) dose distributions for the dynamic rotation with the two small radiosurgical fields were calculated in a spherical water phantom using a modified version of the fast XVMC Monte Carlo code and the validated models of the machine. The dose distributions in a horizontal plane at the isocenter of the linac were measured with low-speed radiographic film. The maximum sizes of the Monte Carlo-calculated 50% isodose surfaces in this horizontal plane were 2.3 mm for the 1.5 mm diameter beam and 3.8 mm for the 3 mm diameter beam. The maximum discrepancies between the 50% isodose surface on the film and the 50% Monte Carlo-calculated isodose surfaces were 0.3 mm for both the 1.5 and 3 mm beams. In addition, the displacement of the delivered dose distributions with respect to the laser-defined isocenter of the machine was studied. The results showed that dynamic radiosurgery with very small beams has a potential for clinical use.

  12. Treatment Plan Technique and Quality for Single-Isocenter Stereotactic Ablative Radiotherapy of Multiple Lung Lesions with Volumetric-Modulated Arc Therapy or Intensity-Modulated Radiosurgery

    OpenAIRE

    Quan, Kimmen; Xu, Karen M.; Lalonde, Ron; Horne, Zachary D.; BERNARD, MARK E.; McCoy, Chuck; Clump, David A.; Steven A Burton; Dwight E Heron

    2015-01-01

    The aim of this study is to provide a practical approach to the planning technique and evaluation of plan quality for the multi-lesion, single-isocenter stereotactic ablative radiotherapy (SABR) of the lung. Eleven patients with two or more lung lesions underwent single-isocenter volumetric-modulated arc therapy (VMAT) radiosurgery or IMRS. All plans were normalized to the target maximum dose. For each plan, all targets were treated to the same dose. Plan conformity and dose gradient were max...

  13. Treatment plan technique and quality for single-isocenter stereotactic ablative radiotherapy of multiple lung lesions with volumetric modulated arc therapy or intensity-modulated radiosurgery

    OpenAIRE

    Kimmen eQuan; Karen Mann Xu; Ron eLalonde; Horne, Zachary D.; BERNARD, MARK E.; Chuck eMcCoy; David Anthony Clump; Steven eBurton; Dwight E Heron

    2015-01-01

    Purpose: The aim is to provide a practical approach to the planning technique and evaluation of plan quality for the multi-lesion, single-isocenter stereotactic ablative radiotherapy (SABR) of the lung. Methods and Materials: Eleven patients with 2 or more lung lesions underwent single-isocenter VMAT radiosurgery or IMRS. All plans were normalized to the target maximum dose. For each plan, all targets were treated to the same dose. Plan conformity and dose gradient were maximized with dose...

  14. Hypofractionated stereotactic radiotherapy for dumbbell-shaped hypoglossal schwannomas: Two cases of long-term follow-up and a review of the literature

    Science.gov (United States)

    Li, Yong; Lou, Jinrong; Qiu, Shujun; Guo, Yutian; Pan, Mianshun

    2016-01-01

    Cases of hypoglossal schwannoma are extremely rare. Historically, microsurgical resection has been the standard treatment, but it may not always be feasible; thus, it is crucial to investigate alternative treatments. We herein present the cases of two patients, both of whom presented with tongue deviation and hemiatrophy, accompanied by headaches. Magnetic resonance imaging revealed a dumbbell-shaped tumor originating from the hypoglossal nerve that was adjacent to the cranial base in each patient. Hypofractionated stereotactic radiotherapy was used to treat the tumors, with a total dose of 30 Gy in 3-Gy fractions delivered to the planning target volume. Several months later, the tumors had significantly decreased in size and the symptoms of the two patients had gradually improved. PMID:27446582

  15. Stereotactic radiosurgery with the gamma knife for brain metastases in patients with lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Morikawa, Tetsuyuki; Takeuchi, Kouichiro; Fujino, Hideyo; Fukumura, Motoyuki; Kimura, Midori; Furuie, Hitoshi; Nagano, Naotomi; Kakuta, Yukio; Tashiro, Yukio [Yokohama Rosai Hospital (Japan)

    1995-01-01

    Between February 1992 and April 1993, six patients with lung cancer were treated with gamma knife radiosurgery for brain metastases. Five patients had adenocarcinoma, and one patient had small cell carcinoma. Two patients had solitary metastases, and four patients had multiple metastases. Twelve metastases were treated with the gamma knife (peripheral dose between 12 Gy and 25 Gy). After radiosurgery, three complete and eight partial responses were achieved, which resulted in an overall response rate of 92%. In two patients, histological studies showed that few viable cells were surrounded by necrosis. Neurological status improved in all patients, and none died of complications. However, four of six patients later developed new intracranial metastases outside the treatment field. These data suggest that radiosurgery with the gamma knife is effective against brain metastases in patients with lung cancer, especially when the lesions are deep in the brain. (author).

  16. Ten-Year Survival of a Patient Treated with Stereotactic Gamma Knife Radiosurgery for Brain Metastases from Colon Cancer with Ovarian and Lymph Node Metastases: A Case Report.

    Science.gov (United States)

    Morinaga, Nobuhiro; Tanaka, Naritaka; Shitara, Yoshinori; Ishizaki, Masatoshi; Yoshida, Takatomo; Kouga, Hideaki; Wakabayashi, Kazuki; Fukuchi, Minoru; Tsunoda, Yoshiyuki; Kuwano, Hiroyuki

    2016-01-01

    Brain metastasis from colorectal cancer is infrequent and carries a poor prognosis. Herein, we present a patient alive 10 years after the identification of a first brain metastasis from sigmoid colon cancer. A 39-year-old woman underwent sigmoidectomy for sigmoid colon cancer during an emergency operation for pelvic peritonitis. The pathological finding was moderately differentiated adenocarcinoma. Eleven months after the sigmoidectomy, a metastatic lesion was identified in the left ovary. Despite local radiotherapy followed by chemotherapy, the left ovarian lesion grew, so resection of the uterus and bilateral ovaries was performed. Adjuvant chemotherapy with tegafur-uracil (UFT)/calcium folinate (leucovorin, LV) was initiated. Seven months after resection of the ovarian lesion, brain metastases appeared in the bilateral frontal lobes and were treated with stereotactic Gamma Knife radiosurgery. Cervical and mediastinal lymph node metastases were also diagnosed, and irradiation of these lesions was performed. After radiotherapy, 10 courses of oxaliplatin and infused fluorouracil plus leucovorin (FOLFOX) were administered. During FOLFOX administration, recurrent left frontal lobe brain metastasis was diagnosed and treated with stereotactic Gamma Knife radiosurgery. In this case, the brain metastases were well treated with stereotactic Gamma Knife radiosurgery, and the systemic disease arising from sigmoid colon cancer has been kept under control with chemotherapies, surgical resection, and radiotherapy.

  17. Ten-Year Survival of a Patient Treated with Stereotactic Gamma Knife Radiosurgery for Brain Metastases from Colon Cancer with Ovarian and Lymph Node Metastases: A Case Report

    Directory of Open Access Journals (Sweden)

    Nobuhiro Morinaga

    2016-05-01

    Full Text Available Brain metastasis from colorectal cancer is infrequent and carries a poor prognosis. Herein, we present a patient alive 10 years after the identification of a first brain metastasis from sigmoid colon cancer. A 39-year-old woman underwent sigmoidectomy for sigmoid colon cancer during an emergency operation for pelvic peritonitis. The pathological finding was moderately differentiated adenocarcinoma. Eleven months after the sigmoidectomy, a metastatic lesion was identified in the left ovary. Despite local radiotherapy followed by chemotherapy, the left ovarian lesion grew, so resection of the uterus and bilateral ovaries was performed. Adjuvant chemotherapy with tegafur-uracil (UFT/calcium folinate (leucovorin, LV was initiated. Seven months after resection of the ovarian lesion, brain metastases appeared in the bilateral frontal lobes and were treated with stereotactic Gamma Knife radiosurgery. Cervical and mediastinal lymph node metastases were also diagnosed, and irradiation of these lesions was performed. After radiotherapy, 10 courses of oxaliplatin and infused fluorouracil plus leucovorin (FOLFOX were administered. During FOLFOX administration, recurrent left frontal lobe brain metastasis was diagnosed and treated with stereotactic Gamma Knife radiosurgery. In this case, the brain metastases were well treated with stereotactic Gamma Knife radiosurgery, and the systemic disease arising from sigmoid colon cancer has been kept under control with chemotherapies, surgical resection, and radiotherapy.

  18. Stereotactic radiosurgery for type 2 neurofibromatosis acoustic neuromas: patient selection and tumour size.

    Science.gov (United States)

    Rowe, Jeremy G; Radatz, Matthias; Walton, Lee; Kemeny, Andras A

    2002-01-01

    Acoustic neuromas which are secondary to type 2 neurofibromatosis (NF2) respond less well to radiosurgery than unilateral sporadic disease. To refine the selection of these patients, a regression analysis was performed examining the response to radiosurgery of 114 NF2 tumours. The major determinant of outcome was tumour volume (p < 0.001). Calculating sensitivity and specificity values for different tumour volume limits gives a sensitivity value of 0.96 for a volume limit of 10 cm(3). This suggests that the size constraints that apply to the radiosurgical management of NF2 acoustic neuromas differ and are more restricted than those which are accepted for acoustic neuromas in general.

  19. The impact of microsurgery, stereotactic radiosurgery and radiotherapy in the treatment of meningiomas depending on different localizations

    Directory of Open Access Journals (Sweden)

    Zimolong, Andreas

    2010-03-01

    Full Text Available Scientific background: Meningiomas are the most common benign intracranial neoplasms with a slow growth presented as the intracranial lesion. These tumors are without any symptoms for a long time. At the time of diagnosis it is frequently an asymptomatic tumor. In that case the therapist may well suggest a wait-and-see strategy. The therapy of meningiomas focuses firstly on the microsurgical treatment. Volume reduction can be achieved immediately after treatment. Stereotactic radiosurgery is an important non-invasive treatment option for recurrent tumors or meningiomas with partial resection. The technical equipment for the stereotactic radiosurgery is a cost intensive investment. In this context the high precision of the intervention, presented as a low invasiveness of the treatment, is an important factor. The aim of this assessment is to identify the chances and limitations of the diverse treatment options and to estimate their outcome for different localisations of meningiomas. Methods: In December 2007 a systematic literature search was conducted using the most relevant medical databases. The whole strategy and the used search terms were documented. The literature search was supplemented with an internet and literature based hand search on law, ethics and economics. Primary studies and systematic reviews which report relevant outcomes are included in this analysis. The current assessment is based on the available evidence that was found at the time of the literature search. Results: A total of 31 publications for the medical focus of assessment and three reports from the economical hand search were included. In general, it is not possible to identify neither randomised clinical trials or prospective, contrasting cohort studies nor studies summarising results from such studies. The results presented in the literature published by surgeons strongly vary regarding localisation of meningiomas. Publications not differentiating between the

  20. Heuristic knowledge-based planning for single-isocenter stereotactic radiosurgery to multiple brain metastases.

    Science.gov (United States)

    Ziemer, Benjamin P; Sanghvi, Parag; Hattangadi-Gluth, Jona; Moore, Kevin L

    2017-07-21

    Single-isocenter, volumetric-modulated arc therapy (VMAT) stereotactic radiosurgery (SRS) for multiple brain metastases (multimets) can deliver highly conformal dose distributions and reduce overall patient treatment time compared to other techniques. However, treatment planning for multimet cases is highly complex due to variability in numbers and sizes of brain metastases, as well as their relative proximity to organs-at-risk (OARs). The purpose of this study was to automate the VMAT planning of multimet cases through a knowledge-based planning (KBP) approach that adapts single-target SRS dose predictions to multiple target predictions. Using a previously published artificial neural network (ANN) KBP system trained on single-target, linac-based SRS plans, 3D dose distribution predictions for multimet patients were obtained by treating each brain lesion as a solitary target and subsequently combining individual dose predictions into a single distribution. Spatial dose distributions di(r→) for each of the i = 1…N lesions were merged using the combination function d(r→)=∑iNdin(r→)1/n. The optimal value of n was determined by minimizing root-mean squared (RMS) difference between clinical multimet plans and predicted dose per unit length along the line profile joining each lesion in the clinical cohort. The gradient measure GM=[3/4π]1/3V50%1/3-V100%1/3 is the primary quality metric for SRS plan evaluation at our institution and served as the main comparative metric between clinical plans and the KBP results. A total of 41 previously treated multimet plans, with target numbers ranging from N = 2-10, were used to validate the ANN predictions and subsequent KBP auto-planning routine. Fully deliverable KBP plans were developed by converting predicted dose distribution into patient-specific optimization objectives for the clinical treatment planning system (TPS). Plan parity was maintained through identical arc configuration and target normalization. Overall

  1. [Linear accelerator-based stereotactic radiosurgery for the treatment of trigeminal neuralgia. Nine years' experience in a single institution].

    Science.gov (United States)

    Serrano-Rubio, A A; Martinez-Manrique, J J; Revuelta-Gutierrez, R; Gomez-Amador, J L; Martinez-Anda, J J; Ponce-Gomez, J A; Moreno-Jimenez, S

    2014-09-16

    INTRODUCTION. Pharmacological treatment is the first therapeutic step towards controlling pain in trigeminal neuralgia, but 25-50% of patients become medication resistant. There are currently several surgical alternatives for treating these patients. AIM. To evaluate the effectiveness and safety of stereotactic radiosurgery for the treatment of patients with trigeminal neuralgia. PATIENTS AND METHODS. A follow-up study was conducted on 30 patients who underwent radiosurgery using a Novalis linear accelerator. Eighty per cent of the dosage was calculated at the isocentre, the entry zone of the root of the trigeminal nerve. The mean follow-up time was 27.5 months (range: 1-65 months). RESULTS. The mean age was 66 years (range: 36-87 years), with a time to progression of 7.1 years (range: 4-27 years). The distribution of the pain was from the right side (63.3%). Of the 30 patients, 27 experienced an improvement (90%) 1.6 months (range: 1 week-4 months) after the treatment; 10 patients (33.3%) scored grade I, and 17 patients (56.6%) obtained a score of grade II. During the follow-up, four patients (14.2%) suffered a relapse; two underwent re-irradiation. Time without recurrence was 62.7 months (range: 54.6-70.8 months). The rate of side effects was 76.7% and only three patients developed facial anaesthesia with loss of the corneal reflex. CONCLUSIONS. The use of the linear accelerator is an effective therapeutic option in the treatment of trigeminal neuralgia, since it provides adequate long-term control of the pain, reduces the use of medication and improves the quality of life.

  2. Potential role for LINAC-based stereotactic radiosurgery for the treatment of 5 or more radioresistant melanoma brain metastases.

    Science.gov (United States)

    Frakes, Jessica M; Figura, Nicholas B; Ahmed, Kamran A; Juan, Tzu-Hua; Patel, Neha; Latifi, Kujtim; Sarangkasiri, Siriporn; Strom, Tobin J; Chinnaiyan, Prakash; Rao, Nikhil G; Etame, Arnold B

    2015-11-01

    Linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) is a treatment option for patients with melanoma in whom brain metastases have developed. Very limited data are available on treating patients with ≥5 lesions. The authors sought to determine the effectiveness of SRS in patients with ≥5 melanoma brain metastases. A retrospective analysis of metastatic melanoma treated with SRS in a single treatment session for ≥5 lesions was performed. Magnetic resonance imaging studies were reviewed post-SRS to evaluate local control (LC). Disease progression on imaging was defined using the 2009 Response Evaluation Criteria in Solid Tumors (RECIST). Survival curves were calculated from the date of brain metastases diagnosis or the date of SRS by using the Kaplan-Meier (KM) method. Univariate and multivariate analysis (UVA and MVA, respectively) were performed using the Cox proportional-hazards model. The authors identified 149 metastatic brain lesions treated in 28 patients. The median patient age was 60.5 years (range 38-83 years), and the majority of patients (24 [85.7%]) had extracranial metastases. Four patients (14.3%) had received previous whole-brain radiotherapy (WBRT), and 11 (39.3%) had undergone previous SRS. The median planning target volume (PTV) was 0.34 cm3 (range 0.01-12.5 cm3). Median follow-up was 6.3 months (range 1-46 months). At the time of treatment, 7% of patients were categorized as recursive partitioning analysis (RPA) Class I, 89% as RPA Class II, and 4% as RPA Class III. The rate of local failure was 11.4%. Kaplan-Meier LC estimates at 6 and 12 months were 91.3% and 82.2%, respectively. A PTV volume≥0.34 cm3 was a significant predictor of local failure on UVA (HR 16.1, 95% CI 3.2-292.6, ptreatment. The RPA class was a significant predictor of KM OS estimates from the date of treatment (p=0.02). Patients who did not receive WBRT after SRS treatment had decreased OS on MVA (HR 3.5, 95% CI 1.1-12.0, p=0.03), and patients who did not

  3. Dose Verification of Stereotactic Radiosurgery Treatment for Trigeminal Neuralgia with Presage 3D Dosimetry System

    OpenAIRE

    2010-01-01

    Achieving adequate verification and quality-assurance (QA) for radiosurgery treatment of trigeminal-neuralgia (TGN) is particularly challenging because of the combination of very small fields, very high doses, and complex irradiation geometries (multiple gantry and couch combinations). TGN treatments have extreme requirements for dosimetry tools and QA techniques, to ensure adequate verification. In this work we evaluate the potential of Presage/Optical-CT dosimetry system as a tool for the v...

  4. Correlation between heterogeneity index (HI) and gradient index (GI) for high dose stereotactic radiotherapy/radiosurgery (SRT/SRS)

    Science.gov (United States)

    Tas, B.; Durmus, I. F.; Okumus, A.; Uzel, O. E.

    2017-02-01

    To evaluate between Heterogeneity Index (HI) and Gradient Index (GI) correlation for high dose Stereotactic radiotherapy (SRT) / Stereotactic radiosurgery (SRS) using Versa HD® lineer accelerator. Nine patients with single metastasis were used in this study. Patient's treatment planning were performed using Monaco5.1® Treatment planning system (TPS) with non-coplanar 6MV Flattening filter free (FFF) beams by partial Volumetric modulated arc therapy (VMAT) tecnique for each patient. We determined three different size of metastasis catagory which are less than 1cc, between 1cc and 5cc and larger than 5cc volume. Also, three different HI were calculated for each patients. These are 1.10, 1.20 and 1.30. Mean GI was determined 8.57±2.2 for 1.10 HI, 7.23±1.7 for 1.20 HI and 6.0±1.1 for 1.30 HI for less than 1cc metastasis. Then GI was determined 4.77±0.4 for 1.10 HI, 4.37±0.3 for 1.20 HI and 3.97±0.3 for 1.30 HI for between 1cc and 5cc metastasis. Finally, GI was determined 4.00±0.5 for 1.10 HI,3.63±0.5 for 1.20 HI and 3.27±0.4 for 1.30 HI for larger than 5cc metastasis. These results show that GI depends on significantly size and HI of metastasis especially for less than 1cc.

  5. Practical Implementation of Failure Mode and Effects Analysis for Safety and Efficiency in Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Younge, Kelly Cooper, E-mail: kyounge@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Wang, Yizhen [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Thompson, John; Giovinazzo, Julia; Finlay, Marisa [Department of Radiation Oncology, Trillium Health Partners - Credit Valley Hospital Site, Mississauga Halton/Central West Regional Cancer Program, Mississauga, ON (Canada); Sankreacha, Raxa [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2015-04-01

    Purpose: To improve the safety and efficiency of a new stereotactic radiosurgery program with the application of failure mode and effects analysis (FMEA) performed by a multidisciplinary team of health care professionals. Methods and Materials: Representatives included physicists, therapists, dosimetrists, oncologists, and administrators. A detailed process tree was created from an initial high-level process tree to facilitate the identification of possible failure modes. Group members were asked to determine failure modes that they considered to be the highest risk before scoring failure modes. Risk priority numbers (RPNs) were determined by each group member individually and then averaged. Results: A total of 99 failure modes were identified. The 5 failure modes with an RPN above 150 were further analyzed to attempt to reduce these RPNs. Only 1 of the initial items that the group presumed to be high-risk (magnetic resonance imaging laterality reversed) was ranked in these top 5 items. New process controls were put in place to reduce the severity, occurrence, and detectability scores for all of the top 5 failure modes. Conclusions: FMEA is a valuable team activity that can assist in the creation or restructuring of a quality assurance program with the aim of improved safety, quality, and efficiency. Performing the FMEA helped group members to see how they fit into the bigger picture of the program, and it served to reduce biases and preconceived notions about which elements of the program were the riskiest.

  6. Analysis of tenth-value-layers for common shielding materials for a robotically mounted stereotactic radiosurgery machine.

    Science.gov (United States)

    Rodgers, James E

    2007-04-01

    Tenth-value-layers (TVLs) for a 6 MV stereotactic radiosurgery (SRS) x-ray beam have been computed using Monte Carlo methods for radiation transport simulation. The first and equilibrium TVLs were determined in the three most common building materials used in radiation therapy vault construction: ordinary concrete, lead, and steel (iron). In contrast to broad-beam 6 MV TVL data found in the literature, the SRS TVLs can change rapidly with the size of the radiation field incident on the barrier. This research has investigated characteristics of TVLs as a function of field size (diameter) at the barrier for all materials, with special attention given to the TVL properties in iron. The x-ray spectrum used to perform these simulations was generated for the CyberKnife accelerator with the BEAMnrc Monte Carlo code. Using this spectrum as input to the MCNP5 Monte Carlo code, predicted tissue-maximum-ratio (TMR) values for a 6-cm-diameter field (at 80 cm from the target) were benchmarked against measured TMR data. The MCNP5 code was used to simulate all barrier transmissions, keeping the standard error of each data point below 1% of the mean. Results compare very well with previous measured concrete TVLs and also with published broad-beam 6 MV TVL data for all three barrier materials.

  7. Long-term Survival After Stereotactic Radiosurgery of Brain Metastases: A Case Series with 10-year Follow-up.

    Science.gov (United States)

    Ampil, Federico; Ellika, Shehanaz; Nanda, Anil; Vora, Moiz

    2017-09-01

    Patients with brain metastases (BRM) generally have a poor prognosis with infrequent long-term outcomes. Four patients treated by stereotactic radiosurgery (SRS) for BRM between 2000 and 2010 with a minimum follow-up of 10 years are described. The mean age was 43.5 years, and these individuals exhibited good performance status at the time of diagnosis of intracranial disease. BRM was solitary or multiple, and the primary malignant tumor originated from the thyroid gland, lung, mediastinum or large intestine. Progression of the original and secondary tumors subsequent to diagnosis and SRS was not observed. Radioimaging of the brain obtained 9 years later in one of the patients who was asymptomatic at follow-up revealed white matter changes; BRM in this individual was treated by tumor resection and cranial irradiation prior to SRS. We contend that extended longevity is not precluded when standard management of BRM is practiced in selected cases. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  8. Low incidence of new biochemical and clinical hypogonadism following hypofractionated stereotactic body radiation therapy (SBRT monotherapy for low- to intermediate-risk prostate cancer

    Directory of Open Access Journals (Sweden)

    Pahira John

    2011-03-01

    Full Text Available Abstract Background The CyberKnife is an appealing delivery system for hypofractionated stereotactic body radiation therapy (SBRT because of its ability to deliver highly conformal radiation therapy to moving targets. This conformity is achieved via 100s of non-coplanar radiation beams, which could potentially increase transitory testicular irradiation and result in post-therapy hypogonadism. We report on our early experience with CyberKnife SBRT for low- to intermediate-risk prostate cancer patients and assess the rate of inducing biochemical and clinical hypogonadism. Methods Twenty-six patients were treated with hypofractionated SBRT to a dose of 36.25 Gy in 5 fractions. All patients had histologically confirmed low- to intermediate-risk prostate adenocarcinoma (clinical stage ≤ T2b, Gleason score ≤ 7, PSA ≤ 20 ng/ml. PSA and total testosterone levels were obtained pre-treatment, 1 month post-treatment and every 3 months thereafter, for 1 year. Biochemical hypogonadism was defined as a total serum testosterone level below 8 nmol/L. Urinary and gastrointestinal toxicity was assessed using Common Toxicity Criteria v3; quality of life was assessed using the American Urological Association Symptom Score, Sexual Health Inventory for Men and Expanded Prostate Cancer Index Composite questionnaires. Results All 26 patients completed the treatment with a median 15 months (range, 13-19 months follow-up. Median pre-treatment PSA was 5.75 ng/ml (range, 2.3-10.3 ng/ml, and a decrease to a median of 0.7 ng/ml (range, 0.2-1.8 ng/ml was observed by one year post-treatment. The median pre-treatment total serum testosterone level was 13.81 nmol/L (range, 5.55 - 39.87 nmol/L. Post-treatment testosterone levels slowly decreased with the median value at one year follow-up of 10.53 nmol/L, significantly lower than the pre-treatment value (p Conclusions Hypofractionated SBRT offers the radiobiological benefit of a large fraction size and is well-tolerated by

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

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, Sai; Srinivas, Chilukuri; Ramalingam, K.; Babaiah, M.; Swamy, S. Thirumalai; Arun, G.; Kathirvel, M.; Ashok, S. [Yashoda Super Specialty Hospital, Hyderabad (India); Clivio, Alessandro [Oncology Institute of Southern Switzerland, Bellinzona (Switzerland); Fogliata, Antonella, E-mail: antonella.fogliata-cozzi@eoc.ch [Oncology Institute of Southern Switzerland, Bellinzona (Switzerland); Nicolini, Giorgia [Oncology Institute of Southern Switzerland, Bellinzona (Switzerland); Rao, K. Srinivasa; Reddy, T. Pratap; Amit, Jotwani [Yashoda Super Specialty Hospital, Hyderabad (India); Vanetti, Eugenio; Cozzi, Luca [Oncology Institute of Southern Switzerland, Bellinzona (Switzerland)

    2012-03-01

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

  10. Sharpening peripheral dose gradient via beam number enhancement from patient head tilt for stereotactic brain radiosurgery

    Science.gov (United States)

    Chiu, Joshua; Pierce, Marlon; Braunstein, Steve E.; Theodosopoulos, Philip V.; McDermott, Michael W.; Sneed, Penny K.; Ma, Lijun

    2016-10-01

    Sharp dose fall-off is the hallmark of brain radiosurgery for the purpose of delivering high dose radiation to the target while minimizing peripheral dose to regional normal brain tissue. In this study, a technique was developed to enhance the peripheral dose gradient by magnifying the total number of beams focused toward each isocenter through pre-programmed patient head tilting. This technique was tested in clinical settings on a dedicated brain radiosurgical system (GKPFX, Gamma Knife Perfexion, Elekta Oncology) by comparing dosimetry as well as delivery efficiency for 20 radiosurgical cases previously treated with the system. The 3-fold beam number enhancement (BNE) treatment plans were found to produce nearly identical target volume coverage (absolute value    0.2) and dose conformity (BNE CI  =  1.41  ±  0.22 versus 1.41  ±  0.11, P  >  0.99) as the original treatment plans. The total beam-on time for the 3-fold BNE treatment plans were also found to be comparable (peripheral dose gradient for brain radiosurgery. This work was presented in part at the 2015 ISRS Congress in Yokohama Japan.

  11. Changing utilization of stereotactic radiosurgery in the UK: the Sheffield experience.

    Science.gov (United States)

    Rowe, J G; Radatz, M W R; Walton, L; Kemeny, A A

    2002-10-01

    Recognizing a change in our workload and variabilities in referral patterns, we reviewed our previous activity from 1994 to 2000 retrospectively and examined prospectively formal referrals to the Unit in 2001. Arteriovenous malformations still constitute 30% of referrals and treatments, although as a proportion of our workload, this has declined. Radiosurgery is increasingly being chosen as a first line treatment for small and moderate-sized acoustic neuromas, although referral rates vary widely, some neuroscience units referring all and others none of their acoustic neuromas at least for a radiosurgical opinion. About 100 meningiomas, mainly skull-base and/or recurrent tumours after previous surgery, are now treated per year. Compared with other units world-wide, very few pituitary adenomas and cerebral metastases are treated. The implications of this are discussed.

  12. Stereotactic radiosurgery for vestibular schwannomas: average 10-year follow-up results focusing on long-term hearing preservation.

    Science.gov (United States)

    Watanabe, Shinya; Yamamoto, Masaaki; Kawabe, Takuya; Koiso, Takao; Yamamoto, Tetsuya; Matsumura, Akira; Kasuya, Hidetoshi

    2016-12-01

    OBJECTIVE The aim of this study was to reappraise long-term treatment outcomes of stereotactic radiosurgery (SRS) for vestibular schwannomas (VSs). The authors used a database that included patients who underwent SRS with a unique dose-planning technique, i.e., partial tumor coverage designed to avoid excess irradiation of the facial and cochlear nerves, focusing on tumor control and hearing preservation. Clinical factors associated with post-SRS tumor control and long-term hearing preservation were also analyzed. METHODS This institutional review board-approved, retrospective cohort study used the authors' prospectively accumulated database. Among 207 patients who underwent Gamma Knife SRS for VSs between 1990 and 2005, 183 (who were followed up for at least 36 post-SRS months) were studied. The median tumor volume was 2.0 cm(3) (range 0.05-26.2 cm(3)). The median prescribed dose at the tumor periphery was 12.0 Gy (range 8.8-15.0 Gy; 12.0 Gy was used in 171 patients [93%]), whereas tumor portions facing the facial and cochlear nerves were irradiated with 10.0 Gy. As a result, 72%-99% of each tumor was irradiated with the prescribed dose. The mean cochlear doses ranged from 2.3 to 5.7 Gy (median 4.1 Gy). RESULTS The median durations of imaging and audiometric follow-up were 114 months (interquartile range 73-144 months) and 59 months (interquartile range 33-109 months), respectively. Tumor shrinkage was documented in 110 (61%), no change in 48 (27%), and enlargement in the other 22 (12%) patients. A further procedure (FP) was required in 15 (8%) patients. Thus, the tumor growth control rate was 88% and the clinical control rate (i.e., no need for an FP) was 92%. The cumulative FP-free rates were 96%, 93%, and 87% at the 60th, 120th, and 180th post-SRS month, respectively. Six (3%) patients experienced facial pain, and 2 developed transient facial palsy. Serviceable hearing was defined as a pure tone audiogram result better than 50 dB. Among the 66 patients with

  13. SU-E-T-404: Evaluation of the Effect of Spine Hardware for CyberKnife Spinal Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, J; Zhang, Y; Zheng, Y; Wessels, B; Machtay, M; Yao, M; Lo, S [University Hospitals Case Medical Center, Cleveland, OH (United States)

    2015-06-15

    Purpose: Spine hardware made of high-Z materials such as titanium has the potential to affect the dose distribution around the metal rods in CyberKnife spinal stereotactic radiosurgery (SRS) treatments. The purpose of this work was to evaluate the magnitude of such effect retrospectively for clinical CyberKnife plans. Methods: The dose calculation was performed within the MultiPlan treatment planning system using the ray tracing (RT) and Monte Carlo (MC) method. A custom density model was created by extending the CT-to-Density table to titanium density of 4.5 g/cm3 with the CT number of 4095. To understand the dose perturbation caused by the titanium rod, a simple beam setup (7.5 mm IRIS collimator) was used to irradiate a mimic rod (5 mm) with overridden high density. Five patient spinal SRS cases were found chronologically from 2010 to 2015 in our institution. For each case, the hardware was contoured manually. The original plan was re-calculated using both RT and MC methods with and without rod density override without changing clinical beam parameters. Results: The simple beam irradiation shows that there is 10% dose increase at the interface because of electron backscattering and 7% decrease behind the rod because of photon attenuation. For actual clinical plans, the iso-dose lines and DVHs are almost identical (<2%) for calculations with and without density override for both RT and MC methods. However, there is a difference of more than 10% for D90 between RT and MC method. Conclusion: Although the dose perturbation around the metal rods can be as large as 10% for a single beam irradiation, for clinical treatments with complex beam composition the effect of spinal hardware to the PTV and spinal dose is minimal. As such, the MC dose algorithm without rod density override for CyberKnife spinal SRS is acceptable.

  14. Prognostic Factors for Survival in Patients Treated With Stereotactic Radiosurgery for Recurrent Brain Metastases After Prior Whole Brain Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Caballero, Jorge A. [Stanford University School of Medicine, Stanford, CA (United States); Sneed, Penny K., E-mail: psneed@radonc.ucsf.edu [Department of Radiation Oncology, University of California, San Francisco, CA (United States); Lamborn, Kathleen R. [Department of Neurological Surgery, University of California, San Francisco, CA (United States); Ma, Lijun [Department of Radiation Oncology, University of California, San Francisco, CA (United States); Denduluri, Sandeep [Department of Radiology, Tulane School of Medicine, New Orleans, LA (United States); Nakamura, Jean L.; Barani, Igor J. [Department of Radiation Oncology, University of California, San Francisco, CA (United States); McDermott, Michael W. [Department of Radiation Oncology, University of California, San Francisco, CA (United States); Department of Neurological Surgery, University of California, San Francisco, CA (United States)

    2012-05-01

    Purpose: To evaluate prognostic factors for survival after stereotactic radiosurgery (SRS) for new, progressive, or recurrent brain metastases (BM) after prior whole brain radiotherapy (WBRT). Methods and Materials: Patients treated between 1991 and 2007 with Gamma Knife SRS for BM after prior WBRT were retrospectively reviewed. Potential prognostic factors were analyzed overall and by primary site using univariate and stepwise multivariate analyses and recursive partitioning analysis, including age, Karnofsky performance status (KPS), primary tumor control, extracranial metastases, number of BM treated, total SRS target volume, and interval from WBRT to SRS. Results: A total of 310 patients were analyzed, including 90 breast, 113 non-small-cell lung, 31 small-cell lung, 42 melanoma, and 34 miscellaneous patients. The median age was 56, KPS 80, number of BM treated 3, and interval from WBRT to SRS 8.1 months; 76% had controlled primary tumor and 60% had extracranial metastases. The median survival was 8.4 months overall and 12.0 vs. 7.9 months for single vs. multiple BM treated (p = 0.001). There was no relationship between number of BM and survival after excluding single-BM patients. On multivariate analysis, favorable prognostic factors included age <50, smaller total target volume, and longer interval from WBRT to SRS in breast cancer patients; smaller number of BM, KPS >60, and controlled primary in non-small-cell lung cancer patients; and smaller total target volume in melanoma patients. Conclusions: Among patients treated with salvage SRS for BM after prior WBRT, prognostic factors appeared to vary by primary site. Although survival time was significantly longer for patients with a single BM, the median survival time of 7.9 months for patients with multiple BM seems sufficiently long for salvage SRS to appear to be worthwhile, and no evidence was found to support the use of a cutoff for number of BM appropriate for salvage SRS.

  15. The Prognostic Role of Tumor Volume in the Outcome of Patients with Single Brain Metastasis After Stereotactic Radiosurgery.

    Science.gov (United States)

    Bennett, E Emily; Angelov, Lilyana; Vogelbaum, Michael A; Barnett, Gene H; Chao, Samuel T; Murphy, Erin S; Yu, Jennifer S; Suh, John H; Jia, Xuefei; Stevens, Glen H J; Ahluwalia, Manmeet S; Mohammadi, Alireza M

    2017-08-01

    Patients with single brain metastasis (SBM) have better outcomes after stereotactic radiosurgery (SRS). We analyzed our SRS database to evaluate possible prognostic factors in patients with SBM. A total of 584 patients with SBM were treated with SRS at our institution (2000-2012). Study end points were overall survival (OS), and distant and local intracranial progression-free survival (DPFS and LPFS, respectively). Multivariable analysis was performed to develop prognostic models. Median OS was 10.8 months. A total of 196 patients (36.7%) had distant progression and 102 patients (19.2%) had local progression. New SBM prognostic indices (SPIs) were devised for OS, DPFS, and LPFS. Graded prognostic assessment, neurologic symptoms (P = 0.01), and tumor volume (P = 0.02) were independently associated with OS. The SPI for OS was defined: unfavorable (OS, 7.3 months), intermediate (OS, 10.6 months), and favorable (OS, 19.8 months). For DPFS, age (P = 0.0029), tumor volume (P = 0.0002), and previous whole-brain radiotherapy (P = 0.027) were prognostic and were used to define SPI for DPFS: favorable (6-month cumulative incidence failure [CIF], 10.9%), intermediate (6-month CIF, 16.7%), and unfavorable (6-month CIF, 26.0%) (P CIF, 12.3%) and favorable (6-month CIF, 6%) (P < 0.001). This is the largest series of patients with SBM treated with SRS analyzed for OS, LPFS, and DPFS. SPI was devised for end points. Tumor volume had a significant association with all 3 end points. Neurologic symptoms, age, and previous whole-brain radiotherapy were also found to be prognostic. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Postoperative Stereotactic Radiosurgery Without Whole-Brain Radiation Therapy for Brain Metastases: Potential Role of Preoperative Tumor Size

    Energy Technology Data Exchange (ETDEWEB)

    Hartford, Alan C., E-mail: Alan.C.Hartford@Hitchcock.org [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Paravati, Anthony J. [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Spire, William J. [Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Li, Zhongze [Biostatistics Shared Resource, Norris Cotton Cancer Center, Lebanon, New Hampshire (United States); Jarvis, Lesley A. [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Fadul, Camilo E. [Section of Hematology/Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Rhodes, C. Harker [Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Erkmen, Kadir [Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Friedman, Jonathan [Department of Surgery, Texas A and M College of Medicine, College Station, Texas (United States); Gladstone, David J. [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Hug, Eugen B. [ProCure, New York, New York (United States); Roberts, David W.; Simmons, Nathan E. [Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States)

    2013-03-01

    Purpose: Radiation therapy following resection of a brain metastasis increases the probability of disease control at the surgical site. We analyzed our experience with postoperative stereotactic radiosurgery (SRS) as an alternative to whole-brain radiotherapy (WBRT), with an emphasis on identifying factors that might predict intracranial disease control and overall survival (OS). Methods and Materials: We retrospectively reviewed all patients through December 2008, who, after surgical resection, underwent SRS to the tumor bed, deferring WBRT. Multiple factors were analyzed for time to intracranial recurrence (ICR), whether local recurrence (LR) at the surgical bed or “distant” recurrence (DR) in the brain, for time to WBRT, and for OS. Results: A total of 49 lesions in 47 patients were treated with postoperative SRS. With median follow-up of 9.3 months (range, 1.1-61.4 months), local control rates at the resection cavity were 85.5% at 1 year and 66.9% at 2 years. OS rates at 1 and 2 years were 52.5% and 31.7%, respectively. On univariate analysis (preoperative) tumors larger than 3.0 cm exhibited a significantly shorter time to LR. At a cutoff of 2.0 cm, larger tumors resulted in significantly shorter times not only for LR but also for DR, ICR, and salvage WBRT. While multivariate Cox regressions showed preoperative size to be significant for times to DR, ICR, and WBRT, in similar multivariate analysis for OS, only the graded prognostic assessment proved to be significant. However, the number of intracranial metastases at presentation was not significantly associated with OS nor with other outcome variables. Conclusions: Larger tumor size was associated with shorter time to recurrence and with shorter time to salvage WBRT; however, larger tumors were not associated with decrements in OS, suggesting successful salvage. SRS to the tumor bed without WBRT is an effective treatment for resected brain metastases, achieving local control particularly for tumors up to

  17. Multidose Stereotactic Radiosurgery (9 Gy × 3) of the Postoperative Resection Cavity for Treatment of Large Brain Metastases

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    Minniti, Giuseppe, E-mail: gminniti@ospedalesantandrea.it [Radiation Oncology Unit, Sant' Andrea Hospital, University “Sapienza,” Rome (Italy); Department of Neurological Sciences, Scientific Institute IRCCS Neuromed, Pozzilli (Italy); Esposito, Vincenzo [Department of Neurological Sciences, Scientific Institute IRCCS Neuromed, Pozzilli (Italy); Clarke, Enrico; Scaringi, Claudia [Radiation Oncology Unit, Sant' Andrea Hospital, University “Sapienza,” Rome (Italy); Lanzetta, Gaetano [Department of Neurological Sciences, Scientific Institute IRCCS Neuromed, Pozzilli (Italy); Salvati, Maurizio [Department of Neurological Sciences, Scientific Institute IRCCS Neuromed, Pozzilli (Italy); Neurosurgery Unit, Umberto I Hospital, University “Sapienza,” Rome (Italy); Raco, Antonino [Neurosurgery Unit, Sant' Andrea Hospital, University “Sapienza,” Rome (Italy); Bozzao, Alessandro [Neuroradiology Unit, Sant' Andrea Hospital, University “Sapienza,” Rome (Italy); Maurizi Enrici, Riccardo [Radiation Oncology Unit, Sant' Andrea Hospital, University “Sapienza,” Rome (Italy)

    2013-07-15

    Purpose: To evaluate the clinical outcomes with linear accelerator-based multidose stereotactic radiosurgery (SRS) to large postoperative resection cavities in patients with large brain metastases. Methods and Materials: Between March 2005 to May 2012, 101 patients with a single brain metastasis were treated with surgery and multidose SRS (9 Gy × 3) for large resection cavities (>3 cm). The target volume was the resection cavity with the inclusion of a 2-mm margin. The median cavity volume was 17.5 cm{sup 3} (range, 12.6-35.7 cm{sup 3}). The primary endpoint was local control. Secondary endpoints were survival and distant failure rates, cause of death, performance measurements, and toxicity of treatment. Results: With a median follow-up of 16 months (range, 6-44 months), the 1-year and 2-year actuarial survival rates were 69% and 34%, respectively. The 1-year and 2-year local control rates were 93% and 84%, with respective incidences of new distant brain metastases of 50% and 66%. Local control was similar for radiosensitive (non-small cell lung cancer and breast cancer) and radioresistant (melanoma and renal cell cancer) brain metastases. On multivariate Cox analysis stable extracranial disease, breast cancer histology, and Karnofsky performance status >70 were associated with significant survival benefit. Brain radionecrosis occurred in 9 patients (9%), being symptomatic in 5 patients (5%). Conclusions: Adjuvant multidose SRS to resection cavity represents an effective treatment option that achieves excellent local control and defers the use of whole-brain radiation therapy in selected patients with large brain metastases.

  18. Systemic Expression of Vascular Endothelial Growth Factor in Patients with Cerebral Cavernous Malformation Treated by Stereotactic Radiosurgery.

    Science.gov (United States)

    Park, Sang-Jin; Park, Seong-Hyun

    2016-09-01

    Increased expression of angiogenic factors, such as vascular endothelial growth factor (VEGF), is associated with the pathogenesis of cerebral cavernous malformations (CCMs). The purpose of this study was to investigate plasma levels of VEGF in normal subjects and in patients with CCM and to evaluate change in these levels following stereotactic radiosurgery (SRS). Peripheral venous blood was collected from 6 patients with CCM before SRS using Gamma Knife and at the 1 week, 1 month, 3month, and 6 month follow-up visits. Plasma VEGF levels were measured using commercially available enzyme-linked immunosorbent assay kits. Peripheral blood samples were obtained from 10 healthy volunteers as controls. Mean plasma VEGF level of 41.9 pg/mL (range, 11.7-114.9 pg/mL) in patients with CCM at baseline was higher than that of the healthy controls (29.3 pg/mL, range, 9.2-64.3 pg/mL), without significant differences between CCM patients and controls (p=0.828). Plasma VEGF level following SRS dropped to 24.6 pg/mL after 1 week, and decreased to 18.5 pg/mL after 1 month, then increased to 24.3 pg/mL after 3 months, and 32.6 pg/mL after 6 months. Two patients suffering from rebleeding after SRS showed a higher level of VEGF at 6 months after SRS than their pretreatment level. Plasma VEGF levels in patients with CCM were elevated over controls at baseline, and decreased from baseline to 1 month after SRS and increased further for up to 6 months. Theses results indicated that anti-angiogenic effect of SRS might play a role in the treatment of CCMs.

  19. A national survey of the availability of intensity-modulated radiation therapy and stereotactic radiosurgery in Canada

    Directory of Open Access Journals (Sweden)

    AlDuhaiby Eman Z

    2012-02-01

    Full Text Available Abstract Background The timely and appropriate adoption of new radiation therapy (RT technologies is a challenge both in terms of providing of optimal patient care and managing health care resources. Relatively little is known regarding the rate at which new RT technologies are adopted in different jurisdictions, and the barriers to implementation of these technologies. Methods Surveys were sent to all radiation oncology department heads in Canada regarding the availability of RT equipment from 2006 to 2010. Data were collected concerning the availability and use of Intensity Modulated Radiation Therapy (IMRT and stereotactic radiosurgery (SRS, and the obstacles to implementation of these technologies. Results IMRT was available in 37% of responding centers in 2006, increasing to 87% in 2010. In 2010, 72% of centers reported that IMRT was available for all patients who might benefit, and 37% indicated that they used IMRT for "virtually all" head and neck patients. SRS availability increased from 26% in 2006 to 42.5% in 2010. Eighty-two percent of centers reported that patients had access to SRS either directly or by referral. The main barriers for IMRT implementation included the need to train or hire treatment planning staff, whereas barriers to SRS implementation mostly included the need to purchase and/or upgrade existing planning software and equipment. Conclusions The survey showed a growing adoption of IMRT and SRS in Canada, although the latter was available in less than half of responding centers. Barriers to implementation differed for IMRT compared to SRS. Enhancing human resources is an important consideration in the implementation of new RT technologies, due to the multidisciplinary nature of the planning and treatment process.

  20. Risk of Leptomeningeal Disease in Patients Treated With Stereotactic Radiosurgery Targeting the Postoperative Resection Cavity for Brain Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Atalar, Banu [Department of Radiation Oncology, Acibadem University School of Medicine, Istanbul (Turkey); Modlin, Leslie A. [Department of Radiation Oncology, Stanford University Medical Center, Stanford, California (United States); Choi, Clara Y.H.; Adler, John R. [Department of Neurosurgery, Stanford University Medical Center, Stanford, California (United States); Gibbs, Iris C. [Department of Radiation Oncology, Stanford University Medical Center, Stanford, California (United States); Chang, Steven D.; Harsh, Griffith R.; Li, Gordon [Department of Neurosurgery, Stanford University Medical Center, Stanford, California (United States); Nagpal, Seema [Department of Neurology, Stanford University Medical Center, Stanford, California (United States); Hanlon, Alexandra [Department of Radiation Oncology, Stanford University Medical Center, Stanford, California (United States); Soltys, Scott G., E-mail: sgsoltys@stanford.edu [Department of Radiation Oncology, Stanford University Medical Center, Stanford, California (United States)

    2013-11-15

    Purpose: We sought to determine the risk of leptomeningeal disease (LMD) in patients treated with stereotactic radiosurgery (SRS) targeting the postsurgical resection cavity of a brain metastasis, deferring whole-brain radiation therapy (WBRT) in all patients. Methods and Materials: We retrospectively reviewed 175 brain metastasis resection cavities in 165 patients treated from 1998 to 2011 with postoperative SRS. The cumulative incidence rates, with death as a competing risk, of LMD, local failure (LF), and distant brain parenchymal failure (DF) were estimated. Variables associated with LMD were evaluated, including LF, DF, posterior fossa location, resection type (en-bloc vs piecemeal or unknown), and histology (lung, colon, breast, melanoma, gynecologic, other). Results: With a median follow-up of 12 months (range, 1-157 months), median overall survival was 17 months. Twenty-one of 165 patients (13%) developed LMD at a median of 5 months (range, 2-33 months) following SRS. The 1-year cumulative incidence rates, with death as a competing risk, were 10% (95% confidence interval [CI], 6%-15%) for developing LF, 54% (95% CI, 46%-61%) for DF, and 11% (95% CI, 7%-17%) for LMD. On univariate analysis, only breast cancer histology (hazard ratio, 2.96) was associated with an increased risk of LMD. The 1-year cumulative incidence of LMD was 24% (95% CI, 9%-41%) for breast cancer compared to 9% (95% CI, 5%-14%) for non-breast histology (P=.004). Conclusions: In patients treated with SRS targeting the postoperative cavity following resection, those with breast cancer histology were at higher risk of LMD. It is unknown whether the inclusion of whole-brain irradiation or novel strategies such as preresection SRS would improve this risk or if the rate of LMD is inherently higher with breast histology.

  1. Outcomes and Prognostic Factors in Women With 1 to 3 Breast Cancer Brain Metastases Treated With Definitive Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T. Jonathan [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Oh, Jung Hun [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Folkert, Michael R.; Gupta, Gaorav [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Shi, Weiji; Zhang, Zhigang [Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Morikawa, Aki; Seidman, Andrew [Department of Medical Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Brennan, Cameron [Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Yamada, Yoshiya; Chan, Timothy A. [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Beal, Kathryn, E-mail: BealK@MSKCC.org [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States)

    2014-11-01

    Background: With the continuing increase in the use of definitive stereotactic radiosurgery (SRS) for patients with limited brain metastases (BM), clinicians need more specific prognostic tools. We investigated clinical predictors of outcomes in patients with limited breast cancer BM treated with SRS alone. Methods and Materials: We identified 136 patients with breast cancer and 1-3 BM who underwent definitive SRS for 186 BM between 2000 and 2012. The Kaplan-Meier method was used to assess overall survival (OS), regional failure (RF), and local failure (LF). Associations between clinical factors and outcomes were tested using Cox regression. A point scoring system was used to stratify patients based on OS, and the predictive power was tested with concordance probability estimate (CPE). Results: The median OS was 17.6 months. The 12-month RF and LF rates were 45% and 10%, respectively. On multivariate analysis, >1 lesion (hazard ratio [HR] = 1.6, P=.02), triple-negative (TN) disease (HR=2.0, P=.006), and active extracranial disease (ED) (HR=2.7, P<.0001) were significantly associated with worse OS. The point score system was defined using proportional simplification of the multivariate Cox proportional hazards regression function. The median OS for patients with 3.0-4.0 points (n=37), 4.5-5.5 points (n=28), 6.0-6.5 points (n=37), and 8-8.5 points (n=34) were 9.2, 15.6, 25.1, and 45.1 months, respectively (P<.0001, CPE = 0.72). Active ED (HR=2.4, P=.0007) was significantly associated with RF. Higher risk for LF was significantly associated with larger BM size (HR=3.1, P=.0001). Conclusion: Patients with >1 BM, active ED, and TN had the highest risk of death after SRS. Active ED is an important prognostic factor for OS and intracranial control.

  2. Repeat Courses of Stereotactic Radiosurgery (SRS), Deferring Whole-Brain Irradiation, for New Brain Metastases After Initial SRS

    Energy Technology Data Exchange (ETDEWEB)

    Shultz, David B.; Modlin, Leslie A.; Jayachandran, Priya; Von Eyben, Rie; Gibbs, Iris C. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Choi, Clara Y.H. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Department of Radiation Oncology, Santa Clara Valley Medical Center, San Jose, California (United States); Chang, Steven D.; Harsh, Griffith R.; Li, Gordon; Adler, John R. [Department of Neurosurgery, Stanford University School of Medicine, Stanford, California (United States); Hancock, Steven L. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Soltys, Scott G., E-mail: sgsoltys@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States)

    2015-08-01

    Purpose: To report the outcomes of repeat stereotactic radiosurgery (SRS), deferring whole-brain radiation therapy (WBRT), for distant intracranial recurrences and identify factors associated with prolonged overall survival (OS). Patients and Methods: We retrospectively identified 652 metastases in 95 patients treated with 2 or more courses of SRS for brain metastases, deferring WBRT. Cox regression analyzed factors predictive for OS. Results: Patients had a median of 2 metastases (range, 1-14) treated per course, with a median of 2 courses (range, 2-14) of SRS per patient. With a median follow-up after first SRS of 15 months (range, 3-98 months), the median OS from the time of the first and second course of SRS was 18 (95% confidence interval [CI] 15-24) and 11 months (95% CI 6-17), respectively. On multivariate analysis, histology, graded prognostic assessment score, aggregate tumor volume (but not number of metastases), and performance status correlated with OS. The 1-year cumulative incidence, with death as a competing risk, of local failure was 5% (95% CI 4-8%). Eighteen (24%) of 75 deaths were from neurologic causes. Nineteen patients (20%) eventually received WBRT. Adverse radiation events developed in 2% of SRS sites. Conclusion: Multiple courses of SRS, deferring WBRT, for distant brain metastases after initial SRS, seem to be a safe and effective approach. The graded prognostic assessment score, updated at each course, and aggregate tumor volume may help select patients in whom the deferral of WBRT might be most beneficial.

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

    Science.gov (United States)

    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.

  4. Use of Stereotactic Radiosurgery for Brain Metastases From Non-Small Cell Lung Cancer in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Halasz, Lia M., E-mail: lhalasz@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Harvard Radiation Oncology Program, Harvard Medical School, Boston, Massachusetts (United States); Weeks, Jane C.; Neville, Bridget A.; Taback, Nathan [Division of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Punglia, Rinaa S. [Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States)

    2013-02-01

    Purpose: The indications for treatment of brain metastases from non-small cell lung cancer (NSCLC) with stereotactic radiosurgery (SRS) remain controversial. We studied patterns, predictors, and cost of SRS use in elderly patients with NSCLC. Methods and Materials: Using the Surveillance, Epidemiology, and End Results-Medicare (SEER-Medicare) database, we identified patients with NSCLC who were diagnosed with brain metastases between 2000 and 2007. Our cohort included patients treated with radiation therapy and not surgical resection as initial treatment for brain metastases. Results: We identified 7684 patients treated with radiation therapy within 2 months after brain metastases diagnosis, of whom 469 (6.1%) cases had billing codes for SRS. Annual SRS use increased from 3.0% in 2000 to 8.2% in 2005 and varied from 3.4% to 12.5% by specific SEER registry site. After controlling for clinical and sociodemographic characteristics, we found SRS use was significantly associated with increasing year of diagnosis, specific SEER registry, higher socioeconomic status, admission to a teaching hospital, no history of participation in low-income state buy-in programs (a proxy for Medicaid eligibility), no extracranial metastases, and longer intervals from NSCLC diagnosis. The average cost per patient associated with radiation therapy was 2.19 times greater for those who received SRS than for those who did not. Conclusions: The use of SRS in patients with metastatic NSCLC increased almost 3-fold from 2000 to 2005. In addition, we found significant variations in SRS use across SEER registries and socioeconomic quartiles. National practice patterns in this study suggested both a lack of consensus and an overall limited use of the approach among elderly patients before 2008.

  5. SU-E-T-751: Three-Component Kinetic Model of Tumor Growth and Radiation Response for Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Y; Dahlman, E; Leder, K; Hui, S [University of Minnesota, Minneapolis, MN (United States)

    2015-06-15

    Purpose: To develop and study a kinetic model of tumor growth and its response to stereotactic radiosurgery (SRS) by assuming that the cells in irradiated tumor volume were made of three types. Methods: A set of ordinary differential equations (ODEs) were derived for three types of cells and a tumor growth rate. It is assumed that the cells were composed of actively proliferating cells, lethally damaged-dividing cells, and non-dividing cells. We modeled the tumor volume growth with a time-dependent growth rate to simulate the saturation of growth. After SRS, the proliferating cells were permanently damaged and converted to the lethally damaged cells. The amount of damaged cells were estimated by the LQ-model. The damaged cells gradually stopped dividing/proliferating and died with a constant rate. The dead cells were cleared from their original location with a constant rate. The total tumor volume was the sum of the three components. The ODEs were numerically solved with appropriate initial conditions for a given dosage. The proposed model was used to model an animal experiment, for which the temporal change of a rhabdomyosarcoma tumor volume grown in a rat was measured with time resolution sufficient to test the model. Results: To fit the model to the experimental data, the following characteristics were needed with the model parameters. The α-value in the LQ-model was smaller than the commonly used value; furthermore, it decreased with increasing dose. At the same time, the tumor growth rate after SRS had to increase. Conclusions: The new 3-component model of tumor could simulate the experimental data very well. The current study suggested that the radiation sensitivity and the growth rate of the proliferating tumor cells may change after irradiation and it depended on the dosage used for SRS. These preliminary observations must be confirmed by future animal experiments.

  6. MRI-based polymer gel dosimetry for validating plans with multiple matrices in Gamma Knife stereotactic radiosurgery.

    Science.gov (United States)

    Gopishankar, N; Watanabe, Yoichi; Subbiah, Vivekanandhan

    2011-01-31

    One of treatment planning techniques with Leksell GammaPlan (LGP) for Gamma Knife stereotactic radiosurgery (GKSRS) uses multiple matrices with multiple dose prescriptions. Computational complexity increases when shots are placed in multiple matrices with different grid sizes. Hence, the experimental validation of LGP calculated dose distributions is needed for those cases. For the current study, we used BANG3 polymer gel contained in a head-sized glass bottle to simulate the entire treatment process of GKSRS. A treatment plan with three 18 mm shots and one 8 mm shot in separate matrices was created with LGP. The prescribed maximum dose was 8 Gy to three shots and 16 Gy to one of the 18 mm shots. The 3D dose distribution recorded in the gel dosimeter was read using a Siemens 3T MRI scanner. The scanning parameters of a CPMG pulse sequence with 32 equidistant echoes were as follows: TR = 7 s, echo step = 13.6 ms, field-of-view = 256 mm × 256 mm, and pixel size = 1 mm × 1 mm. Interleaved acquisition mode was used to obtain 15 to 45 2-mm-thick slices. Using a calibration relationship between absorbed dose and the spin-spin relaxation rate (R2), we converted R2 images to dose images. MATLAB-based in-house programs were used for R2 estimation and dose comparison. Gamma-index analysis for the 3D data showed gamma values less than unity for 86% of the voxels. Through this study we accomplished the first application of polymer gel dosimetry for a true comparison between measured 3D dose distributions and LGP calculations for plans using multiple matrices for multiple targets.

  7. Local control after stereotactic radiosurgery for brain metastases in patients with melanoma with and without BRAF mutation and treatment.

    Science.gov (United States)

    Ly, David; Bagshaw, Hilary P; Anker, Christopher J; Tward, Jonathan D; Grossmann, Kenneth F; Jensen, Randy L; Shrieve, Dennis C

    2015-08-01

    BRAF inhibitors improve progression-free and overall survival in patients with metastatic melanoma. Brain metastases are common, and stereotactic radiosurgery (SRS) has been used, resulting in excellent local control. Because BRAF inhibitors are associated with intracranial responses, the authors hypothesized that BRAF inhibitors would improve local control in patients with melanoma who are receiving SRS for brain metastases. The authors retrospectively identified patients with metastatic melanoma who had been tested for BRAF mutation and treated with SRS for brain metastases. Patients with previous resection, multiple brain metastases, or multiple courses of SRS were eligible. SRS was delivered in a single fraction to a median dose of 2000 cGy. Patients with a BRAF mutation were treated with a BRAF inhibitor on the basis of physician preference. The authors identified 52 patients who were treated in 82 treatment sessions for 185 brain metastases and 13 tumor beds. At a median follow-up of 10.5 months, the 1-year local control rate was 69.2%. At 1 year, the local control rate for brain metastases in patients with BRAF mutation with BRAF treatment was 85.0%, and the local control rate for brain metastases in those without BRAF treatment was 51.5% (p = 0.0077). The rates of distant brain failure, freedom from whole-brain radiation, and overall survival were not different on the basis of BRAF mutation status or inhibitor therapy. The number of new intratumoral hemorrhages after SRS was increased significantly in patients with BRAF treatment. Treatment with BRAF inhibitors was associated with improved local control after SRS in patients with melanoma and brain metastases. An increased number of intratumoral hemorrhages was associated with BRAF inhibitor therapy.

  8. Clinical results of stereotactic helium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Levy, R.P.; Fabrikant, J.I.; Lyman, J.T.; Frankel, K.A.; Phillips, M.H.; Lawrence, J.H.; Tobias, C.A.

    1989-12-01

    The first therapeutic clinical trial using accelerated heavy-charged particles in humans was performed for the treatment of various endocrine and metabolic disorders of the pituitary gland, and as suppressive therapy for adenohypophyseal hormone-responsive carcinomas and diabetic retinopathy. Since then, over 800 patients have received stereotactically-directed plateau-beam heavy-charged particle pituitary irradiation at this institution. In acromegaly, Cushing's disease, Nelson's syndrome and prolactin-secreting tumors, the therapeutic goal in the 433 patients treated has been to destroy or inhibit the growth of the pituitary tumor and control hormonal hypersecretion, while preserving a functional rim of tissue with normal hormone-secreting capacity, and minimizing neurologic injury. An additional group of 34 patients was treated for nonsecreting chromophobe adenomas. This paper discusses the methods and results of these treatments. 11 refs.

  9. Dosimetric performance of the new high-definition multileaf collimator for intracranial stereotactic radiosurgery.

    Science.gov (United States)

    Dhabaan, Anees; Elder, Eric; Schreibmann, Eduard; Crocker, Ian; Curran, Walter J; Oyesiku, Nelson M; Shu, Hui-Kuo; Fox, Tim

    2010-06-21

    The objective was to evaluate the performance of a high-definition multileaf collimator (MLC) of 2.5 mm leaf width (MLC2.5) and compare to standard 5 mm leaf width MLC (MLC5) for the treatment of intracranial lesions using dynamic conformal arcs (DCA) technique with a dedicated radiosurgery linear accelerator. Simulated cases of spherical targets were created to study solely the effect of target volume size on the performance of the two MLC systems independent of target shape complexity. In addition, 43 patients previously treated for intracranial lesions in our institution were retrospectively planned using DCA technique with MLC2.5 and MLC5 systems. The gross tumor volume ranged from 0.07 to 40.57 cm3 with an average volume of 5.9 cm3. All treatment parameters were kept the same for both MLC-based plans. The plan evaluation was performed using figures of merits (FOM) for a rapid and objective assessment on the quality of the two treatment plans for MLC2.5 and MLC5. The prescription isodose surface was selected as the greatest isodose surface covering >or= 95% of the target volume and delivering 95% of the prescription dose to 99% of target volume. A Conformity Index (CI) and conformity distance index (CDI) were used to quantifying the dose conformity to a target volume. To assess normal tissue sparing, a normal tissue difference (NTD) was defined as the difference between the volume of normal tissue receiving a certain dose utilizing MLC5 and the volume receiving the same dose using MLC2.5. The CI and normal tissue sparing for the simulated spherical targets were better with the MLC2.5 as compared to MLC5. For the clinical patients, the CI and CDI results indicated that the MLC2.5 provides better treatment conformity than MLC5 even at large target volumes. The CI's range was 1.15 to 2.44 with a median of 1.59 for MLC2.5 compared to 1.60-2.85 with a median of 1.71 for MLC5. Improved normal tissue sparing was also observed for MLC2.5 over MLC5, with the NTD always

  10. Evaluation of the peripheral dose in stereotactic radiotherapy and radiosurgery treatments

    Energy Technology Data Exchange (ETDEWEB)

    Di Betta, Erika; Fariselli, Laura; Bergantin, Achille; Locatelli, Federica; Del Vecchio, Antonella; Broggi, Sara; Fumagalli, Maria Luisa [Department of Neurosurgery, Division of Medical Physics, Fondazione IRCCS, Istituto Neurologico C. Besta, 20133 Milano (Italy); Department of Neurosurgery, Division of Radiotherapy, Fondazione IRCCS, Istituto Neurologico C. Besta, 20133 Milano (Italy); CyberKnife Centre, Centro Diagnostico Italiano, 20147 Milano (Italy); Division of Medical Physics, Fondazione IRCCS, Istituto S. Raffaele, 20132 Milano (Italy); Department of Neurosurgery, Division of Medical Physics, Fondazione IRCCS, Istituto Neurologico C. Besta, 20133 Milano (Italy)

    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.

  11. Dose Verification of Stereotactic Radiosurgery Treatment for Trigeminal Neuralgia with Presage 3D Dosimetry System

    Science.gov (United States)

    Wang, Z.; Thomas, A.; Newton, J.; Ibbott, G.; Deasy, J.; Oldham, M.

    2010-11-01

    Achieving adequate verification and quality-assurance (QA) for radiosurgery treatment of trigeminal-neuralgia (TGN) is particularly challenging because of the combination of very small fields, very high doses, and complex irradiation geometries (multiple gantry and couch combinations). TGN treatments have extreme requirements for dosimetry tools and QA techniques, to ensure adequate verification. In this work we evaluate the potential of Presage/Optical-CT dosimetry system as a tool for the verification of TGN distributions in high-resolution and in 3D. A TGN treatment was planned and delivered to a Presage 3D dosimeter positioned inside the Radiological-Physics-Center (RPC) head and neck IMRT credentialing phantom. A 6-arc treatment plan was created using the iPlan system, and a maximum dose of 80Gy was delivered with a Varian Trilogy machine. The delivered dose to Presage was determined by optical-CT scanning using the Duke Large field-of-view Optical-CT Scanner (DLOS) in 3D, with isotropic resolution of 0.7mm3. DLOS scanning and reconstruction took about 20minutes. 3D dose comparisons were made with the planning system. Good agreement was observed between the planned and measured 3D dose distributions, and this work provides strong support for the viability of Presage/Optical-CT as a highly useful new approach for verification of this complex technique.

  12. Image guidance quality assurance of a G4 CyberKnife robotic stereotactic radiosurgery system

    Energy Technology Data Exchange (ETDEWEB)

    Pantelis, E; Antypas, C [CyberKnife center, Iatropolis-Magnitiki Tomografia, Ethnikis Antistaseos 54-56, Chalandri, 152 31, Athens (Greece); Petrokokkinos, L [University of Athens, Physics Department, Nuclear and Particle Section, Panepistimioupolis, Ilisia, Athens (Greece)], E-mail: vpantelis@phys.uoa.gr

    2009-05-15

    The image guidance of a CyberKnife robotic radiosurgery system was quality controlled, including the overall performance of the target locating subsystem and the performance of the x-ray generators and flat panel digital cameras subcomponents. Accuracy and precision of the kV and exposure time settings of the x-ray generators, linearity of the x-ray output, spatial resolution and geometrical distortion of the acquired x-ray images were measured. Total accuracy and precision of the target locating subsystem in defining the position of an anthropomorphic head and neck phantom placed on treatment couch was also measured. Accuracy and precision of the kV as well as exposure time settings and linearity of the x-ray output were found within the acceptance limits suggested in diagnostic radiology. The acquired x-ray images were found to depict the shapes of the imaging objects without any geometrical distortion, being able to resolve differences in the features of imaging objects with critical frequency of 1.3 lp/mm and 1.5 lp/mm for camera A and B, respectively. Total target locating system accuracy was found within 0.2 mm and 0.2 deg. in translations and rotations, respectively. Corresponding precision was found lower than 0.5%. These findings render the target locating subsystem of the CyberKnife capable of accurately registering the patient to treatment position and monitoring patient's movement during treatment delivery.

  13. Image guidance quality assurance of a G4 CyberKnife robotic stereotactic radiosurgery system

    Science.gov (United States)

    Pantelis, E.; Petrokokkinos, L.; Antypas, C.

    2009-05-01

    The image guidance of a CyberKnife robotic radiosurgery system was quality controlled, including the overall performance of the target locating subsystem and the performance of the x-ray generators and flat panel digital cameras subcomponents. Accuracy and precision of the kV and exposure time settings of the x-ray generators, linearity of the x-ray output, spatial resolution and geometrical distortion of the acquired x-ray images were measured. Total accuracy and precision of the target locating subsystem in defining the position of an anthropomorphic head and neck phantom placed on treatment couch was also measured. Accuracy and precision of the kV as well as exposure time settings and linearity of the x-ray output were found within the acceptance limits suggested in diagnostic radiology. The acquired x-ray images were found to depict the shapes of the imaging objects without any geometrical distortion, being able to resolve differences in the features of imaging objects with critical frequency of 1.3 lp/mm and 1.5 lp/mm for camera A and B, respectively. Total target locating system accuracy was found within 0.2 mm and 0.2° in translations and rotations, respectively. Corresponding precision was found lower than 0.5%. These findings render the target locating subsystem of the CyberKnife capable of accurately registering the patient to treatment position and monitoring patient's movement during treatment delivery.

  14. Dose Verification of Stereotactic Radiosurgery Treatment for Trigeminal Neuralgia with Presage 3D Dosimetry System

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z; Thomas, A; Newton, J; Ibbott, G; Deasy, J; Oldham, M, E-mail: Zhiheng.wang@duke.ed

    2010-11-01

    Achieving adequate verification and quality-assurance (QA) for radiosurgery treatment of trigeminal-neuralgia (TGN) is particularly challenging because of the combination of very small fields, very high doses, and complex irradiation geometries (multiple gantry and couch combinations). TGN treatments have extreme requirements for dosimetry tools and QA techniques, to ensure adequate verification. In this work we evaluate the potential of Presage/Optical-CT dosimetry system as a tool for the verification of TGN distributions in high-resolution and in 3D. A TGN treatment was planned and delivered to a Presage 3D dosimeter positioned inside the Radiological-Physics-Center (RPC) head and neck IMRT credentialing phantom. A 6-arc treatment plan was created using the iPlan system, and a maximum dose of 80Gy was delivered with a Varian Trilogy machine. The delivered dose to Presage was determined by optical-CT scanning using the Duke Large field-of-view Optical-CT Scanner (DLOS) in 3D, with isotropic resolution of 0.7mm{sup 3}. DLOS scanning and reconstruction took about 20minutes. 3D dose comparisons were made with the planning system. Good agreement was observed between the planned and measured 3D dose distributions, and this work provides strong support for the viability of Presage/Optical-CT as a highly useful new approach for verification of this complex technique.

  15. Results of hemihypoglossal-facial nerve anastomosis in the treatment of facial nerve paralysis after failed stereotactic radiosurgery for vestibular schwannoma.

    Science.gov (United States)

    Dziedzic, Tomasz A; Kunert, Przemysław; Marchel, Andrzej

    2017-04-01

    Vestibular schwannoma treatment with stereotactic radiosurgery (SRS) carries a risk of facial nerve (CNVII) palsy that is lower than that with microneurosurgery. The results of hemihypoglossal-facial nerve anastomosis (HHFA) have not been described yet in CNVII palsy after failed stereotactic radiosurgery (SRS). Here we report a case series of the first four consecutive patients (three women; average age 58.5, age range: 46-74), who underwent HHFA due to failed SRS. All patients were admitted because of progressive peripheral facial nerve palsy. Three patients received retrosigmoid craniotomy due to tumor enlargement that resulted in facial nerve paralysis. All patients achieved satisfactory (House-Brackmann grade III) CNVII regeneration. No or minimal tongue atrophy occurred on the side of the anastomosis. Patients reported no problems with phonation or swallowing, except for the patients with preexisting lower cranial nerve deficits. HHFA effectively treats facial palsy after failed SRS with minimal risk of tongue atrophy and minimal morbidity. The results of the treatment are comparable to those achieved with patients without previous SRS.

  16. Modeling Local Control After Hypofractionated Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer: A Report From the Elekta Collaborative Lung Research Group

    Energy Technology Data Exchange (ETDEWEB)

    Ohri, Nitin, E-mail: ohri.nitin@gmail.com [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Werner-Wasik, Maria [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Grills, Inga S. [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Belderbos, Jose [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Hope, Andrew [Department of Radiation Oncology, Princess Margaret Hospital and University of Toronto, Toronto, ON (Canada); Yan Di; Kestin, Larry L. [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Guckenberger, Matthias [Department of Radiation Oncology, University of Wuerzburg, Wuerzburg (Germany); Sonke, Jan-Jakob [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Bissonnette, Jean-Pierre [Department of Radiation Oncology, Princess Margaret Hospital and University of Toronto, Toronto, ON (Canada); Xiao, Ying [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)

    2012-11-01

    Purpose: Hypofractionated stereotactic body radiation therapy (SBRT) has emerged as an effective treatment option for early-stage non-small cell lung cancer (NSCLC). Using data collected by the Elekta Lung Research Group, we generated a tumor control probability (TCP) model that predicts 2-year local control after SBRT as a function of biologically effective dose (BED) and tumor size. Methods and Materials: We formulated our TCP model as follows: TCP = e{sup [BED10-c Asterisk-Operator L-TCD50]/k} Division-Sign (1 + e{sup [BED10-c Asterisk-Operator L-TCD50]/k}), where BED10 is the biologically effective SBRT dose, c is a constant, L is the maximal tumor diameter, and TCD50 and k are parameters that define the shape of the TCP curve. Least-squares optimization with a bootstrap resampling approach was used to identify the values of c, TCD50, and k that provided the best fit with observed actuarial 2-year local control rates. Results: Data from 504 NSCLC tumors treated with a variety of SBRT schedules were available. The mean follow-up time was 18.4 months, and 26 local recurrences were observed. The optimal values for c, TCD50, and k were 10 Gy/cm, 0 Gy, and 31 Gy, respectively. Thus, size-adjusted BED (sBED) may be defined as BED minus 10 times the tumor diameter (in centimeters). Our TCP model indicates that sBED values of 44 Gy, 69 Gy, and 93 Gy provide 80%, 90%, and 95% chances of tumor control at 2 years, respectively. When patients were grouped by sBED, the model accurately characterized the relationship between sBED and actuarial 2-year local control (r=0.847, P=.008). Conclusion: We have developed a TCP model that predicts 2-year local control rate after hypofractionated SBRT for early-stage NSCLC as a function of biologically effective dose and tumor diameter. Further testing of this model with additional datasets is warranted.

  17. Leptomeningeal failure in patients with breast cancer receiving stereotactic radiosurgery for brain metastases.

    Science.gov (United States)

    Wang, Edina C; Huang, Andrew J; Huang, Karen E; McTyre, Emory R; Lo, Hui-Wen; Watabe, Kounosuke; Metheny-Barlow, Linda; Laxton, Adrian W; Tatter, Stephen B; Strowd, Roy E; Chan, Michael D; Page, Brandi R

    2017-09-01

    Prior studies suggest a high incidence of leptomeningeal failure (LMF) in breast cancer metastatic to brain. This study examines breast cancer-specific variables affecting development of LMF and survival after Gamma-Knife Radiosurgery (GKS). Between 2000-2010, 149 (breast) and 658 other-histology patients were treated with GKS. Hormone/HER2, age, local/distant brain failure, prior craniotomy, and prior whole-brain radiotherapy (WBRT) were assessed. Median follow-up was 54months (range, 0-106). Serial MRI determined local and distant-brain failure and LMF. Statistical analysis with categorical/continuous data comparisons were done with Fisher's-exact, Wilcoxon rank-sum, log-rank tests, and Cox-Proportional Hazard models. Of 149 patients, 21 (14%) developed LMF (median time of 11.9months). None of the following predicted for LMF: Her2-status (HR=0.49, p=0.16), hormone-receptor status (HR=1.15, p=0.79), prior craniotomy (HR=1.58, p=0.42), prior WBRT (HR=1.36, p=0.55). Non-significant factors between patients that did (n=21) and did not (n=106) develop LMF included neurologic death (p=0.34) and median survival (8.6 vs 14.2months, respectively). Breast patients who had distant-failure after GKS (65/149; 43.6%) were more likely to later develop LMF (HR 4.2, p=0.005); including 15/65 (23%) patients who had distant-failure and developed LMF. Median time-to-death for patients experiencing LMF was 6.1months (IQR 3.4-7.8) from onset of LMF. Median survival from LMF to death was much longer in breast (6.1months) than in other (1.7months) histologies CONCLUSION: Breast cancer patients had a longer survival after diagnosis of LMF versus other histologies. Neither ER/PR/HER2 status, nor prior surgery or prior WBRT predicted for development of LMF in breast patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. A Single-Institution Analysis of 126 Patients Treated with Stereotactic Radiosurgery for Brain Metastases

    Directory of Open Access Journals (Sweden)

    Kevin B. Harris

    2017-05-01

    Full Text Available BackgroundThe objective of this study was to report our institutional experience with Gamma Knife® Radiosurgery (GKRS in the treatment of patients with brain metastases.MethodsRetrospectively collected demographic and clinical data on 126 patients with intracranial metastases were reviewed. The patients in our study underwent GKRS at Vidant Medical Center between 2009 and 2014. Kaplan–Meier curves were used to compare survival based on clinical characteristics for univariate analysis, and a Cox proportional hazards model was used for multivariate analysis.ResultsThe median age of the patient population was 62 years. Medicare patients constituted 51% of our patient cohort and Medicaid patients 15%. The most common tumor histologies were non-small cell lung cancer (50%, breast cancer (12.7%, and melanoma (11.9%. The median overall survival time for all patients was 5.8 months. Patients with breast cancer had the longest median survival time of 9.15 months, while patients with melanoma had the shortest median survival time of 2.86 months. On univariate analysis, the following factors were predictors for improved overall survival, ECOG score 0 or 1 vs. 2 or greater (17.0 vs. 1.8 months, p < 0.001, controlled extracranial disease vs. progressive extracranial disease (17.4 vs. 4.6 months, p = 0.0001, recursive partitioning analysis Stage I vs. II–III (18.2 vs. 6.2 months, p < 0.007, multiple GKRS treatments (p = 0.002, prior brain metastasectomy (p = 0.012, and prior chemotherapy (p = 0.021. Age, ethnicity, gender, previous external beam radiation therapy, number of brain metastases, and hemorrhagic vs. non-hemorrhagic tumors were not predictors of longer median survival time. Number of metastatic brain lesions of 1–3 vs. ≥4 (p = 0.051 and insurance status of Medicare/Medicaid vs. commercial insurance approached significance (13.7 vs. 6.8 months, p = 0.08. On multivariate analysis, ECOG

  19. Indirect Tumor Cell Death After High-Dose Hypofractionated Irradiation: Implications for Stereotactic Body Radiation Therapy and Stereotactic Radiation Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Song, Chang W., E-mail: songx001@umn.edu [Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota Medical School, Minneapolis, Minnesota (United States); Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yoon-Jin [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Griffin, Robert J. [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Park, Inhwan [Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota Medical School, Minneapolis, Minnesota (United States); Koonce, Nathan A. [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Hui, Susanta [Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota Medical School, Minneapolis, Minnesota (United States); Kim, Mi-Sook [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Dusenbery, Kathryn E. [Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota Medical School, Minneapolis, Minnesota (United States); Sperduto, Paul W. [Minneapolis Radiation Oncology and Gamma Knife Center, University of Minnesota, Minneapolis, Minnesota (United States); Cho, L. Chinsoo [Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota Medical School, Minneapolis, Minnesota (United States)

    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.

  20. Computational assessment of effective dose and patient specific doses for kilovoltage stereotactic radiosurgery of wet age-related macular degeneration

    Science.gov (United States)

    Hanlon, Justin Mitchell

    Age-related macular degeneration (AMD) is a leading cause of vision loss and a major health problem for people over the age of 50 in industrialized nations. The current standard of care, ranibizumab, is used to help slow and in some cases stabilize the process of AMD, but requires frequent invasive injections into the eye. Interest continues for stereotactic radiosurgery (SRS), an option that provides a non-invasive treatment for the wet form of AMD, through the development of the IRay(TM) (Oraya Therapeutics, Inc., Newark, CA). The goal of this modality is to destroy choroidal neovascularization beneath the pigment epithelium via delivery of three 100 kVp photon beams entering through the sclera and overlapping on the macula delivering up to 24 Gy of therapeutic dose over a span of approximately 5 minutes. The divergent x-ray beams targeting the fovea are robotically positioned and the eye is gently immobilized by a suction-enabled contact lens. Device development requires assessment of patient effective dose, reference patient mean absorbed doses to radiosensitive tissues, and patient specific doses to the lens and optic nerve. A series of head phantoms, including both reference and patient specific, was derived from CT data and employed in conjunction with the MCNPX 2.5.0 radiation transport code to simulate treatment and evaluate absorbed doses to potential tissues-at-risk. The reference phantoms were used to evaluate effective dose and mean absorbed doses to several radiosensitive tissues. The optic nerve was modeled with changeable positions based on individual patient variability seen in a review of head CT scans gathered. Patient specific phantoms were used to determine the effect of varying anatomy and gaze. The results showed that absorbed doses to the non-targeted tissues were below the threshold levels for serious complications; specifically the development of radiogenic cataracts and radiation induced optic neuropathy (RON). The effective dose

  1. A novel phantom and procedure providing submillimeter accuracy in daily QA tests of accelerators used for stereotactic radiosurgery.

    Science.gov (United States)

    Brezovich, Ivan A; Popple, Richard A; Duan, Jun; Shen, Sui; Wu, Xingen; Benhabib, Sidi; Huang, Mi; Cardan, Rex A

    2016-07-08

    Stereotactic radiosurgery (SRS) places great demands on spatial accuracy. Steel BBs used as markers in quality assurance (QA) phantoms are clearly visible in MV and planar kV images, but artifacts compromise cone-beam CT (CBCT) isocenter localization. The purpose of this work was to develop a QA phantom for measuring with sub-mm accuracy isocenter congruence of planar kV, MV, and CBCT imaging systems and to design a practical QA procedure that includes daily Winston-Lutz (WL) tests and does not require computer aid. The salient feature of the phantom (Universal Alignment Ball (UAB)) is a novel marker for precisely localizing isocenters of CBCT, planar kV, and MV beams. It consists of a 25.4mm diameter sphere of polymethylmetacrylate (PMMA) containing a concentric 6.35mm diameter tungsten carbide ball. The large density difference between PMMA and the polystyrene foam in which the PMMA sphere is embedded yields a sharp image of the sphere for accurate CBCT registration. The tungsten carbide ball serves in finding isocenter in planar kV and MV images and in doing WL tests. With the aid of the UAB, CBCT isocenter was located within 0.10 ± 0.05 mm of its true positon, and MV isocenter was pinpointed in planar images to within 0.06 ± 0.04mm. In clinical morning QA tests extending over an 18 months period the UAB consistently yielded measurements with sub-mm accuracy. The average distance between isocenter defined by orthogonal kV images and CBCT measured 0.16 ± 0.12 mm. In WL tests the central ray of anterior beams defined by a 1.5 × 1.5 cm2 MLC field agreed with CBCT isocenter within 0.03 ± 0.14 mm in the lateral direction and within 0.10 ± 0.19 mm in the longitudinal direction. Lateral MV beams approached CBCT isocenter within 0.00 ± 0.11 mm in the vertical direction and within -0.14 ± 0.15 mm longitudinally. It took therapists about 10 min to do the tests. The novel QA phantom allows pinpointing CBCT and MV isocenter positions to better than 0.2 mm, using

  2. Defining the Optimal Planning Target Volume in Image-Guided Stereotactic Radiosurgery of Brain Metastases: Results of a Randomized Trial

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, John P., E-mail: john.kirkpatrick@dm.duke.edu [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Surgery, Duke University, Durham, North Carolina (United States); Wang, Zhiheng [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Sampson, John H. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Surgery, Duke University, Durham, North Carolina (United States); McSherry, Frances; Herndon, James E. [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina (United States); Allen, Karen J.; Duffy, Eileen [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Hoang, Jenny K. [Department of Radiology, Duke University, Durham, North Carolina (United States); Chang, Zheng; Yoo, David S.; Kelsey, Chris R.; Yin, Fang-Fang [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States)

    2015-01-01

    Purpose: To identify an optimal margin about the gross target volume (GTV) for stereotactic radiosurgery (SRS) of brain metastases, minimizing toxicity and local recurrence. Methods and Materials: Adult patients with 1 to 3 brain metastases less than 4 cm in greatest dimension, no previous brain radiation therapy, and Karnofsky performance status (KPS) above 70 were eligible for this institutional review board–approved trial. Individual lesions were randomized to 1- or 3- mm uniform expansion of the GTV defined on contrast-enhanced magnetic resonance imaging (MRI). The resulting planning target volume (PTV) was treated to 24, 18, or 15 Gy marginal dose for maximum PTV diameters less than 2, 2 to 2.9, and 3 to 3.9 cm, respectively, using a linear accelerator–based image-guided system. The primary endpoint was local recurrence (LR). Secondary endpoints included neurocognition Mini-Mental State Examination, Trail Making Test Parts A and B, quality of life (Functional Assessment of Cancer Therapy-Brain), radionecrosis (RN), need for salvage radiation therapy, distant failure (DF) in the brain, and overall survival (OS). Results: Between February 2010 and November 2012, 49 patients with 80 brain metastases were treated. The median age was 61 years, the median KPS was 90, and the predominant histologies were non–small cell lung cancer (25 patients) and melanoma (8). Fifty-five, 19, and 6 lesions were treated to 24, 18, and 15 Gy, respectively. The PTV/GTV ratio, volume receiving 12 Gy or more, and minimum dose to PTV were significantly higher in the 3-mm group (all P<.01), and GTV was similar (P=.76). At a median follow-up time of 32.2 months, 11 patients were alive, with median OS 10.6 months. LR was observed in only 3 lesions (2 in the 1 mm group, P=.51), with 6.7% LR 12 months after SRS. Biopsy-proven RN alone was observed in 6 lesions (5 in the 3-mm group, P=.10). The 12-month DF rate was 45.7%. Three months after SRS, no significant change in

  3. Stereotactic Radiosurgery for Melanoma Brain Metastases in Patients Receiving Ipilimumab: Safety Profile and Efficacy of Combined Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kiess, Ana P. [Department of Radiation Oncology, Johns Hopkins University, Baltimore, Maryland (United States); Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wolchok, Jedd D. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Barker, Christopher A. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Postow, Michael A. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Tabar, Viviane [Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Huse, Jason T. [Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Chan, Timothy A.; Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Beal, Kathryn, E-mail: bealk@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2015-06-01

    Purpose: Ipilimumab (Ipi), a monoclonal antibody against cytotoxic T-lymphocyte antigen-4, has been shown to improve survival in patients with metastatic melanoma. In this single-institution study, we investigated the safety and efficacy of stereotactic radiosurgery (SRS) for patients with melanoma brain metastases (BMs) who also received Ipi. Methods and Materials: From 2005 to 2011, 46 patients with melanoma received Ipi and underwent single-fraction SRS for BMs. A total of 113 BMs (91% intact, 9% postoperative) were treated with a median dose of 21 Gy (range, 15-24 Gy). Ipi was given at 3 mg/kg (54%) or 10 mg/kg (46%) for a median of 4 doses (range, 1-21). Adverse events were recorded with the use of the Common Terminology Criteria for Adverse Events 3.0. Kaplan-Meier methods were used to estimate survival, and Cox regression was used to investigate associations. Results: Fifteen patients received SRS during Ipi, 19 received SRS before Ipi, and 12 received SRS after Ipi. Overall survival (OS) was significantly associated with the timing of SRS/Ipi (P=.035) and melanoma-specific graded prognostic assessment (P=.013). Patients treated with SRS during or before Ipi had better OS and less regional recurrence than did those treated with SRS after Ipi (1-year OS 65% vs 56% vs 40%, P=.008; 1-year regional recurrence 69% vs 64% vs 92%, P=.003). SRS during Ipi also yielded a trend toward less local recurrence than did SRS before or after Ipi (1-year local recurrence 0% vs 13% vs 11%, P=.21). On magnetic resonance imaging, an increase in BM diameter to >150% was seen in 50% of patients treated during or before Ipi but in only 13% of patients treated after Ipi. Grade 3 to 4 toxicities were seen in 20% of patients. Conclusion: Overall, the combination of Ipi and SRS appears to be well tolerated. Concurrent delivery of Ipi and SRS is associated with favorable locoregional control and possibly longer survival. It may also cause a temporary increase in tumor size, possibly

  4. The Risk Factors of Symptomatic Communicating Hydrocephalus After Stereotactic Radiosurgery for Unilateral Vestibular Schwannoma: The Implication of Brain Atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jung Ho [Department of Neurosurgery, Seoul National University Bundang Hospital, Gyeonggi-do (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dong Gyu, E-mail: gknife@plaza.snu.ac.kr [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, Hyun-Tai; Paek, Sun Ha; Park, Chul-Kee [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Chae-Yong [Department of Neurosurgery, Seoul National University Bundang Hospital, Gyeonggi-do (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Hwang, Seung-Sik [Department of Social and Preventive Medicine, Inha University School of Medicine, Incheon (Korea, Republic of); Park, Jeong-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Gyeonggi-do (Korea, Republic of); Kim, Young-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Gyeonggi-do (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Wook; Kim, Yong Hwy; Song, Sang Woo; Kim, In Kyung; Jung, Hee-Won [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2012-11-15

    Purpose: To identify the effect of brain atrophy on the development of symptomatic communicating hydrocephalus (SCHCP) after stereotactic radiosurgery (SRS) for sporadic unilateral vestibular schwannomas (VS). Methods and Materials: A total of 444 patients with VS were treated with SRS as a primary treatment. One hundred eighty-one patients (40.8%) were male, and the mean age of the patients was 53 {+-} 13 years (range, 11-81 years). The mean follow-up duration was 56.8 {+-} 35.8 months (range, 12-160 months). The mean tumor volume was 2.78 {+-} 3.33 cm{sup 3} (range, 0.03-23.30 cm{sup 3}). The cross-sectional area of the lateral ventricles (CALV), defined as the combined area of the lateral ventricles at the level of the mammillary body, was measured on coronal T1-weighted magnetic resonance images as an indicator of brain atrophy. Results: At distant follow-up, a total of 25 (5.6%) patients had SCHCP. The median time to symptom development was 7 months (range, 1-48 months). The mean CALV was 334.0 {+-} 194.0 mm{sup 2} (range, 44.70-1170 mm{sup 2}). The intraclass correlation coefficient was 0.988 (95% confidence interval [CI], 0.976-0.994; p < 0.001). In multivariate analysis, the CALV had a significant relationship with the development of SCHCP (p < 0.001; odds ration [OR] = 1.005; 95% CI, 1.002-1.007). Tumor volume and female sex also had a significant association (p < 0.001; OR = 1.246; 95% CI, 1.103-1.409; p < 0.009; OR = 7.256; 95% CI, 1.656-31.797, respectively). However, age failed to show any relationship with the development of SCHCP (p = 0.364). Conclusion: Brain atrophy may be related to de novo SCHCP after SRS, especially in female patients with a large VS. Follow-up surveillance should be individualized, considering the risk factors involved for each patient, for prompt diagnosis of SCHCP.

  5. SU-D-BRB-04: Plan Quality Comparison of Intracranial Stereotactic Radiosurgery (SRS) for Gamma Knife and VMAT Treatments

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    Keeling, V; Algan, O; Ahmad, S; Hossain, S [University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2015-06-15

    Purpose: To compare treatment plan quality of intracranial stereotactic radiosurgery (SRS) for VMAT (RapidArc) and Gamma Knife (GK) systems. Methods: Ten patients with 24 tumors (seven with 1–2 and three with 4–6 lesions), previously treated with GK 4C (prescription doses ranging from 14–23 Gy) were re-planned for RapidArc. Identical contour sets were kept on MRI images for both plans with tissues assigned a CT number of zero. RapidArc plans were performed using 6 MV flattening-filter-free (FFF) beams with dose rate of 1400 MU/minute using two to eight arcs with the following combinations: 2 full coplanar arcs and the rest non-coplanar half arcs. Beam selection was based on target depth. Areas that penetrated more than 10 cm of tissue were avoided by creating smaller arcs or using avoidance sectors in optimization. Plans were optimized with jaw tracking and a high weighting to the normal-brain-tissue and Normal-Tissue-Objective without compromising PTV coverage. Plans were calculated on a 1 mm grid size using AAA algorithm and then normalized so that 99% of each target volume received the prescription dose. Plan quality was assessed by target coverage using Paddick Conformity Index (PCI), sparing of normal-brain-tissue through analysis of V4, V8, and V12 Gy, and integral dose. Results: In all cases critical structure dose criteria were met. RapidArc had a higher PCI than GK plans for 23 out of 24 lesions. The average PCI was 0.76±0.21 for RapidArc and 0.46±0.20 for GK plans (p≤0.001), respectively. Integral dose and normal-brain-tissue doses for all criteria were lower for RapidArc in nearly all patients. The average ratio of GK to RapidArc plans was 1.28±0.27 (p=0.018), 1.31±0.25 (p=0.017), 1.81±0.43 (p=0.005), and 1.50±0.61 (p=0.006) for V4, V8, and V12 Gy, and integral dose, respectively. Conclusion: VMAT was capable of producing higher quality treatment plans than GK when using optimal beam geometries and proper optimization techniques.

  6. TH-A-9A-08: Knowledge-Based Quality Control of Clinical Stereotactic Radiosurgery Treatment Plans

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    Shiraishi, S; Moore, K L [University of California, San Diego, La Jolla, CA (United States); Tan, J; Olsen, L [Washington University in St. Louis, St. Louis, MO (United States)

    2014-06-15

    Purpose: To develop a quality control tool to reduce stereotactic radiosurgery (SRS) planning variability using models that predict achievable plan quality metrics (QMs) based on individual patient anatomy. Methods: Using a knowledge-based methodology that quantitatively correlates anatomical geometric features to resultant organ-at-risk (OAR) dosimetry, we developed models for predicting achievable OAR dose-volume histograms (DVHs) by training with a cohort of previously treated SRS patients. The DVH-based QMs used in this work are the gradient measure, GM=(3/4pi)^1/3*[V50%^1/3−V100%^1/3], and V10Gy of normal brain. As GM quantifies the total rate of dose fall-off around the planning target volume (PTV), all voxels inside the patient's body contour were treated as OAR for DVH prediction. 35 previously treated SRS plans from our institution were collected; all were planned with non-coplanar volumetric-modulated arc therapy to prescription doses of 12–25 Gy. Of the 35-patient cohort, 15 were used for model training and 20 for model validation. Accuracies of the predictions were quantified by the mean and the standard deviation of the difference between clinical and predicted QMs, δQM=QM-clin−QM-pred. Results: Best agreement between predicted and clinical QMs was obtained when models were built separately for V-PTV<2.5cc and V-PTV>2.5cc. Eight patients trained the V-PTV<2.5cc model and seven patients trained the V-PTV>2.5cc models, respectively. The mean and the standard deviation of δGM were 0.3±0.4mm for the training sets and −0.1±0.6mm for the validation sets, demonstrating highly accurate GM predictions. V10Gy predictions were also highly accurate, with δV10Gy=0.8±0.7cc for the training sets and δV10Gy=0.7±1.4cc for the validation sets. Conclusion: The accuracy of the models in predicting two key SRS quality metrics highlights the potential of this technique for quality control for SRS treatments. Future investigations will seek to determine

  7. TH-A-9A-05: Initial Setup Accuracy Comparison Between Frame-Based and Frameless Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, T; Sheu, R; Todorov, B; Green, S; Blacksburg, S; Lo, Y [Mount Sinai Medical Center, New York, NY (United States)

    2014-06-15

    Purpose: To evaluate initial setup accuracy for stereotactic radiosurgery (SRS) between Brainlab frame-based and frameless immobilization system, also to discern the magnitude frameless system has on setup parameters. Methods: The correction shifts from the original setup were compared for total 157 SRS cranial treatments (69 frame-based vs. 88 frameless). All treatments were performed on a Novalis linac with ExacTrac positioning system. Localization box with isocenter overlay was used for initial setup and correction shift was determined by ExacTrac 6D auto-fusion to achieve submillimeter accuracy for treatment. For frameless treatments, mean time interval between simulation and treatment was 5.7 days (range 0–13). Pearson Chi-Square was used for univariate analysis. Results: The correctional radial shifts (mean±STD, median) for the frame and frameless system measured by ExacTrac were 1.2±1.2mm, 1.1mm and 3.1±3.3mm, 2.0mm, respectively. Treatments with frameless system had a radial shift >2mm more often than those with frames (51.1% vs. 2.9%; p<.0001). To achieve submillimeter accuracy, 85.5% frame-based treatments did not require shift and only 23.9% frameless treatment could succeed with initial setup. There was no statistical significant system offset observed in any direction for either system. For frameless treatments, those treated ≥ 3 days from simulation had statistically higher rates of radial shifts between 1–2mm and >2mm compared to patients treated in a shorter amount of time from simulation (34.3% and 56.7% vs. 28.6% and 33.3%, respectively; p=0.006). Conclusion: Although image-guided positioning system can also achieve submillimeter accuracy for frameless system, users should be cautious regarding the inherent uncertainty of its capability of immobilization. A proper quality assurance procedure for frameless mask manufacturing and a protocol for intra-fraction imaging verification will be crucial for frameless system. Time interval between

  8. Vorinostat and Concurrent Stereotactic Radiosurgery for Non-Small Cell Lung Cancer Brain Metastases: A Phase 1 Dose Escalation Trial.

    Science.gov (United States)

    Choi, Clara Y H; Wakelee, Heather A; Neal, Joel W; Pinder-Schenck, Mary C; Yu, Hsiang-Hsuan Michael; Chang, Steven D; Adler, John R; Modlin, Leslie A; Harsh, Griffith R; Soltys, Scott G

    2017-09-01

    To determine the maximum tolerated dose (MTD) of vorinostat, a histone deacetylase inhibitor, given concurrently with stereotactic radiosurgery (SRS) to treat non-small cell lung cancer (NSCLC) brain metastases. Secondary objectives were to determine toxicity, local failure, distant intracranial failure, and overall survival rates. In this multicenter study, patients with 1 to 4 NSCLC brain metastases, each ≤2 cm, were enrolled in a phase 1, 3 + 3 dose escalation trial. Vorinostat dose levels were 200, 300, and 400 mg orally once daily for 14 days. Single-fraction SRS was delivered on day 3. A dose-limiting toxicity (DLT) was defined as any Common Terminology Criteria for Adverse Events version 3.0 grade 3 to 5 acute nonhematologic adverse event related to vorinostat or SRS occurring within 30 days. From 2009 to 2014, 17 patients were enrolled and 12 patients completed study treatment. Because no DLTs were observed, the MTD was established as 400 mg. Acute adverse events were reported by 10 patients (59%). Five patients discontinued vorinostat early and withdrew from the study. The most common reasons for withdrawal were dyspnea (n=2), nausea (n=1), and fatigue (n=2). With a median follow-up of 12 months (range, 1-64 months), Kaplan-Meier overall survival was 13 months. There were no local failures. One patient (8%) at the 400-mg dose level with a 2.0-cm metastasis developed histologically confirmed grade 4 radiation necrosis 2 months after SRS. The MTD of vorinostat with concurrent SRS was established as 400 mg. Although no DLTs were observed, 5 patients withdrew before completing the treatment course, a result that emphasizes the need for supportive care during vorinostat administration. There were no local failures. A larger, randomized trial may evaluate both the tolerability and potential local control benefit of vorinostat concurrent with SRS for brain metastases. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Predictors of Individual Tumor Local Control After Stereotactic Radiosurgery for Non-Small Cell Lung Cancer Brain Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Garsa, Adam A. [Department of Radiation Oncology, University of California, San Francisco, San Francisco, California (United States); Badiyan, Shahed N.; DeWees, Todd; Simpson, Joseph R.; Huang, Jiayi; Drzymala, Robert E. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States); Barani, Igor J. [Department of Radiation Oncology, University of California, San Francisco, San Francisco, California (United States); Dowling, Joshua L.; Rich, Keith M.; Chicoine, Michael R.; Kim, Albert H.; Leuthardt, Eric C. [Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri (United States); Robinson, Clifford G., E-mail: crobinson@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States)

    2014-10-01

    Purpose: To evaluate local control rates and predictors of individual tumor local control for brain metastases from non-small cell lung cancer (NSCLC) treated with stereotactic radiosurgery (SRS). Methods and Materials: Between June 1998 and May 2011, 401 brain metastases in 228 patients were treated with Gamma Knife single-fraction SRS. Local failure was defined as an increase in lesion size after SRS. Local control was estimated using the Kaplan-Meier method. The Cox proportional hazards model was used for univariate and multivariate analysis. Receiver operating characteristic analysis was used to identify an optimal cutpoint for conformality index relative to local control. A P value <.05 was considered statistically significant. Results: Median age was 60 years (range, 27-84 years). There were 66 cerebellar metastases (16%) and 335 supratentorial metastases (84%). The median prescription dose was 20 Gy (range, 14-24 Gy). Median overall survival from time of SRS was 12.1 months. The estimated local control at 12 months was 74%. On multivariate analysis, cerebellar location (hazard ratio [HR] 1.94, P=.009), larger tumor volume (HR 1.09, P<.001), and lower conformality (HR 0.700, P=.044) were significant independent predictors of local failure. Conformality index cutpoints of 1.4-1.9 were predictive of local control, whereas a cutpoint of 1.75 was the most predictive (P=.001). The adjusted Kaplan-Meier 1-year local control for conformality index ≥1.75 was 84% versus 69% for conformality index <1.75, controlling for tumor volume and location. The 1-year adjusted local control for cerebellar lesions was 60%, compared with 77% for supratentorial lesions, controlling for tumor volume and conformality index. Conclusions: Cerebellar tumor location, lower conformality index, and larger tumor volume were significant independent predictors of local failure after SRS for brain metastases from NSCLC. These results warrant further investigation in a prospective

  10. Trigeminal Neuralgia Treated With Stereotactic Radiosurgery: The Effect of Dose Escalation on Pain Control and Treatment Outcomes.

    Science.gov (United States)

    Kotecha, Rupesh; Kotecha, Ritesh; Modugula, Sujith; Murphy, Erin S; Jones, Mark; Kotecha, Rajesh; Reddy, Chandana A; Suh, John H; Barnett, Gene H; Neyman, Gennady; Machado, Andre; Nagel, Sean; Chao, Samuel T

    2016-09-01

    To analyze the effect of dose escalation on treatment outcome in patients undergoing stereotactic radiosurgery (SRS) for trigeminal neuralgia (TN). A retrospective review was performed of 870 patients who underwent SRS for a diagnosis of TN from 2 institutions. Patients were typically treated using a single 4-mm isocenter placed at the trigeminal nerve dorsal root entry zone. Patients were divided into groups based on treatment doses: ≤82 Gy (352 patients), 83 to 86 Gy (85 patients), and ≥90 Gy (433 patients). Pain response was classified using a categorical scoring system, with fair or poor pain control representing treatment failure. Treatment-related facial numbness was classified using the Barrow Neurological Institute scale. Log-rank tests were performed to test differences in time to pain failure or development of facial numbness for patients treated with different doses. Median age at first pain onset was 63 years, median age at time of SRS was 71 years, and median follow-up was 36.5 months from the time of SRS. A majority of patients (827, 95%) were clinically diagnosed with typical TN. The 4-year rate of excellent to good pain relief was 87% (95% confidence interval 84%-90%). The 4-year rate of pain response was 79%, 82%, and 92% in patients treated to ≤82 Gy, 83 to 86 Gy, and ≥90 Gy, respectively. Patients treated to doses ≤82 Gy had an increased risk of pain failure after SRS, compared with patients treated to ≥90 Gy (hazard ratio 2.0, P=.0007). Rates of treatment-related facial numbness were similar among patients treated to doses ≥83 Gy. Nine patients (1%) were diagnosed with anesthesia dolorosa. Dose escalation for TN to doses >82 Gy is associated with an improvement in response to treatment and duration of pain relief. Patients treated at these doses, however, should be counseled about the increased risk of treatment-related facial numbness. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Stereotactic radiosurgery for spinal metastases: a literature review; Radiocirurgia estereotaxica para metastases de coluna vertebral: revisao de literatura

    Energy Technology Data Exchange (ETDEWEB)

    Joaquim, Andrei Fernandes; Ghizoni, Enrico; Tedeschi, Helder; Pereira, Eduardo Baldon; Giacomini, Leonardo Abdala, E-mail: andjoaquim@yahoo.com [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2013-04-15

    Objective: The spine is the most common location for bone metastases. Since cure is not possible, local control and relief of symptoms is the basis for treatment, which is grounded on the use of conventional radiotherapy. Recently, spinal radiosurgery has been proposed for the local control of spinal metastases, whether as primary or salvage treatment. Consequently, we carried out a literature review in order to analyze the indications, efficacy, and safety of radiosurgery in the treatment of spinal metastases. Methods: We have reviewed the literature using the PubMed gateway with data from the Medline library on studies related to the use of radiosurgery in treatment of bone metastases in spine. The studies were reviewed by all the authors and classified as to level of evidence, using the criterion defined by Wright. Results: The indications found for radiosurgery were primary control of epidural metastases (evidence level II), myeloma (level III), and metastases known to be poor responders to conventional radiotherapy - melanoma and renal cell carcinoma (level III). Spinal radiosurgery was also proposed for salvage treatment after conventional radiotherapy (level II). There is also some evidence as to the safety and efficacy of radiosurgery in cases of extramedullar and intramedullar intradural metastatic tumors (level III) and after spinal decompression and stabilization surgery. Conclusion: Radiosurgery can be used in primary or salvage treatment of spinal metastases, improving local disease control and patient symptoms. It should also be considered as initial treatment for radioresistant tumors, such as melanoma and renal cell carcinoma. (author)

  12. The radiobiology of hypofractionation.

    Science.gov (United States)

    Nahum, Alan E

    2015-05-01

    If the α/β ratio is high (e.g. 10 Gy) for tumour clonogen killing, but low (e.g. 3 Gy) for late normal tissue complications, then delivering external beam radiotherapy in a large number (20-30) of small (≈2 Gy) dose fractions should yield the highest 'therapeutic ratio'; this is demonstrated via the linear-quadratic model of cell killing. However, this 'conventional wisdom' is increasingly being challenged, partly by the success of stereotactic body radiotherapy (SBRT) or stereotactic ablative radiotherapy (SABR) extreme hypofractionation regimens of three to five large fractions for early stage non-small cell lung cancer and partly by indications that for certain tumours (prostate, breast) the α/β ratio may be of the same order or even lower than that characterising late complications. It is shown how highly conformal dose delivery combined with quasi-parallel normal tissue behaviour (n close to 1) enables 'safe' hypofractionation; this can be predicted by the (α/β)eff concept for normal tissues. Recent analyses of the clinical outcomes of non-small cell lung cancer radiotherapy covering 'conventional' hyper- to extreme hypofractionation (stereotactic ablative radiotherapy) regimens are consistent with linear-quadratic radiobiology, even at the largest fraction sizes, despite there being theoretical reasons to expect 'LQ violation' above a certain dose. Impairment of re-oxygenation between fractions and the very high (α/β) for hypoxic cells can complicate the picture regarding the analysis of clinical outcomes; it has also been suggested that vascular damage may play a role for very large dose fractions. Finally, the link between high values of (α/β)eff and normal-tissue sparing for quasi-parallel normal tissues, thereby favouring hypofractionation, may be particularly important for proton therapy, but more generally, improved conformality, achieved by whatever technique, can be translated into individualisation of both prescription dose and fraction

  13. Intrafraction Variation of Mean Tumor Position During Image-Guided Hypofractionated Stereotactic Body Radiotherapy for Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Chirag [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Grills, Inga S., E-mail: igrills@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Kestin, Larry L.; McGrath, Samuel; Ye Hong; Martin, Shannon K.; Yan Di [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States)

    2012-04-01

    Purpose: Prolonged delivery times during daily cone-beam computed tomography (CBCT)-guided lung stereotactic body radiotherapy (SBRT) introduce concerns regarding intrafraction variation (IFV) of the mean target position (MTP). The purpose of this study was to evaluate the magnitude of the IFV-MTP and to assess target margins required to compensate for IFV and postonline CBCT correction residuals. Patient, treatment, and tumor characteristics were analyzed with respect to their impact on IFV-MTP. Methods and Materials: A total of 126 patients with 140 tumors underwent 659 fractions of lung SBRT. Dose prescribed was 48 or 60 Gy in 12 Gy fractions. Translational target position correction of the MTP was performed via onboard CBCT. IFV-MTP was measured as the difference in MTP between the postcorrection CBCT and the posttreatment CBCT excluding residual error. Results: IFV-MTP was 0.2 {+-} 1.8 mm, 0.1 {+-} 1.9 mm, and 0.01 {+-} 1.5 mm in the craniocaudal, anteroposterior, and mediolateral dimensions and the IFV-MTP vector was 2.3 {+-} 2.1 mm. Treatment time and excursion were found to be significant predictors of IFV-MTP. An IFV-MTP vector greater than 2 and 5 mm was seen in 40.8% and 7.2% of fractions, respectively. IFV-MTP greater than 2 mm was seen in heavier patients with larger excursions and longer treatment times. Significant differences in IFV-MTP were seen between immobilization devices. The stereotactic frame immobilization device was found to be significantly less likely to have an IFV-MTP vector greater than 2 mm compared with the alpha cradle, BodyFIX, and hybrid immobilization devices. Conclusions: Treatment time and respiratory excursion are significantly associated with IFV-MTP. Significant differences in IFV-MTP were found between immobilization devices. Target margins for IFV-MTP plus post-correction residuals are dependent on immobilization device with 5-mm uniform margins being acceptable for the frame immobilization device.

  14. Prospective comparison of late 3T MRI with conventional angiography in evaluating the patency of cerebral arteriovenous malformations treated with stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Khandanpour, Nader [National Hospital for Neurology and Neurosurgery, London (United Kingdom); Griffiths, Paul; Hoggard, Nigel [University of Sheffield, Academic Unit of Radiology, C Floor, Royal Hallamshire Hospital, Sheffield (United Kingdom); Warren, Daniel [University of Sheffield, C Floor, Royal Hallamshire Hospital, Sheffield (United Kingdom)

    2013-06-15

    Risk of further haemorrhage in patients suffering from arteriovenous malformation (AVM) would be eliminated only if complete obliteration of the AVM is obtained. Therefore, these patients frequently need long-term follow-up. Conventional catheter angiography (CCA) with a risk of 0.5 %.to 1.6 % of significant neurological complications has traditionally been used for this purpose. However, magnetic resonance imaging (MRI) at 3T may be a safer alternative. The aim of this study was to evaluate if MRI at 3T can accurately evaluate closure of AVM in 2 years after stereotactic radiosurgery. Twenty-three patients with both MRI at 3T and a CCA study were examined. The residual AVMs were evaluated by MRI at 3T against CCA in a prospective study. The time interval between radiosurgery and neuroimaging was on average of 25 months (range, 15-30 months) for MRI study and 33 months (range, 25-46 months) for CCA study. Ten patients showed closure of the AVM on MRI, all of which were confirmed on CCA. There was a complete agreement between late MRI at 3T scan and CCA in evaluation of AVM patency. (orig.)

  15. Gamma knife stereotactic radiosurgery as salvage therapy after failure of whole-brain radiotherapy in patients with small-cell lung cancer.

    Science.gov (United States)

    Harris, Sunit; Chan, Michael D; Lovato, James F; Ellis, Thomas L; Tatter, Stephen B; Bourland, J Daniel; Munley, Michael T; deGuzman, Allan F; Shaw, Edward G; Urbanic, James J; McMullen, Kevin P

    2012-05-01

    Radiosurgery has been successfully used in selected cases to avoid repeat whole-brain irradiation (WBI) in patients with multiple brain metastases of most solid tumor histological findings. Few data are available for the use of radiosurgery for small-cell lung cancer (SCLC). Between November 1999 and June 2009, 51 patients with SCLC and previous WBI and new brain metastases were treated with GammaKnife stereotactic radiosurgery (GKSRS). A median dose of 18 Gy (range, 10-24 Gy) was prescribed to the margin of each metastasis. Patients were followed with serial imaging. Patient electronic records were reviewed to determine disease-related factors and clinical outcomes after GKSRS. Local and distant brain failure rates, overall survival, and likelihood of neurologic death were determined based on imaging results. The Kaplan-Meier method was used to determine survival and local and distant brain control. Cox proportional hazard regression was performed to determine strength of association between disease-related factors and survival. Median survival time for the entire cohort was 5.9 months. Local control rates at 1 and 2 years were 57% and 34%, respectively. Distant brain failure rates at 1 and 2 years were 58% and 75%, respectively. Fifty-three percent of patients ultimately died of neurologic death. On multivariate analysis, patients with stable (hazard ratio [HR] = 2.89) or progressive (HR = 6.98) extracranial disease (ECD) had worse overall survival than patients without evidence of ECD (p = 0.00002). Concurrent chemotherapy improved local control (HR = 89; p = 0.006). GKSRS represents a feasible salvage option in patients with SCLC and brain metastases for whom previous WBI has failed. The status of patients' ECD is a dominant factor predictive of overall survival. Local control may be inferior to that seen with other cancer histological results, although the use of concurrent chemotherapy may help to improve this. Copyright © 2012 Elsevier Inc. All rights

  16. Gamma Knife Stereotactic Radiosurgery as Salvage Therapy After Failure of Whole-Brain Radiotherapy in Patients With Small-Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Sunit [Department of Radiation Oncology, Wake Forest University, Winston-Salem, North Carolina (United States); Chan, Michael D., E-mail: mchan@wfubmc.edu [Department of Radiation Oncology, Wake Forest University, Winston-Salem, North Carolina (United States); Lovato, James F. [Division of Public Health Sciences, Wake Forest University, Winston-Salem, North Carolina (United States); Ellis, Thomas L.; Tatter, Stephen B. [Department of Neurosurgery, Wake Forest University, Winston-Salem, North Carolina (United States); Bourland, J. Daniel; Munley, Michael T.; Guzman, Allan F. de; Shaw, Edward G.; Urbanic, James J.; McMullen, Kevin P. [Department of Radiation Oncology, Wake Forest University, Winston-Salem, North Carolina (United States)

    2012-05-01

    Purpose: Radiosurgery has been successfully used in selected cases to avoid repeat whole-brain irradiation (WBI) in patients with multiple brain metastases of most solid tumor histological findings. Few data are available for the use of radiosurgery for small-cell lung cancer (SCLC). Methods and Materials: Between November 1999 and June 2009, 51 patients with SCLC and previous WBI and new brain metastases were treated with GammaKnife stereotactic radiosurgery (GKSRS). A median dose of 18 Gy (range, 10-24 Gy) was prescribed to the margin of each metastasis. Patients were followed with serial imaging. Patient electronic records were reviewed to determine disease-related factors and clinical outcomes after GKSRS. Local and distant brain failure rates, overall survival, and likelihood of neurologic death were determined based on imaging results. The Kaplan-Meier method was used to determine survival and local and distant brain control. Cox proportional hazard regression was performed to determine strength of association between disease-related factors and survival. Results: Median survival time for the entire cohort was 5.9 months. Local control rates at 1 and 2 years were 57% and 34%, respectively. Distant brain failure rates at 1 and 2 years were 58% and 75%, respectively. Fifty-three percent of patients ultimately died of neurologic death. On multivariate analysis, patients with stable (hazard ratio [HR] = 2.89) or progressive (HR = 6.98) extracranial disease (ECD) had worse overall survival than patients without evidence of ECD (p = 0.00002). Concurrent chemotherapy improved local control (HR = 89; p = 0.006). Conclusions: GKSRS represents a feasible salvage option in patients with SCLC and brain metastases for whom previous WBI has failed. The status of patients' ECD is a dominant factor predictive of overall survival. Local control may be inferior to that seen with other cancer histological results, although the use of concurrent chemotherapy may help to

  17. Hypofractionated image-guided breath-hold SABR (Stereotactic Ablative Body Radiotherapy of liver metastases – clinical results

    Directory of Open Access Journals (Sweden)

    Boda-Heggemann Judit

    2012-06-01

    Full Text Available Abstract Purpose Stereotactic Ablative Body Radiotherapy (SABR is a non-invasive therapy option for inoperable liver oligometastases. Outcome and toxicity were retrospectively evaluated in a single-institution patient cohort who had undergone ultrasound-guided breath-hold SABR. Patients and methods 19 patients with liver metastases of various primary tumors consecutively treated with SABR (image-guidance with stereotactic ultrasound in combination with computer-controlled breath-hold were analysed regarding overall-survival (OS, progression-free-survival (PFS, progression pattern, local control (LC, acute and late toxicity. Results PTV (planning target volume-size was 108 ± 109cm3 (median 67.4 cm3. BED2 (Biologically effective dose in 2 Gy fraction was 83.3 ± 26.2 Gy (median 78 Gy. Median follow-up and median OS were 12 months. Actuarial 2-year-OS-rate was 31%. Median PFS was 4 months, actuarial 1-year-PFS-rate was 20%. Site of first progression was predominantly distant. Regression of irradiated lesions was observed in 84% (median time to detection of regression was 2 months. Actuarial 6-month-LC-rate was 92%, 1- and 2-years-LC-rate 57%, respectively. BED2 influenced LC. When a cut-off of BED2 = 78 Gy was used, the higher BED2 values resulted in improved local control with a statistical trend to significance (p = 0.0999. Larger PTV-sizes, inversely correlated with applied dose, resulted in lower local control, also with a trend to significance (p-value = 0.08 when a volume cut-off of 67 cm3 was used. No local relapse was observed at PTV-sizes 3 and BED2 > 78 Gy. No acute clinical toxicity > °2 was observed. Late toxicity was also ≤ °2 with the exception of one gastrointestinal bleeding-episode 1 year post-SABR. A statistically significant elevation in the acute phase was observed for alkaline-phosphatase; in the chronic phase for alkaline-phosphatase, bilirubine, cholinesterase and C

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

    Energy Technology Data Exchange (ETDEWEB)

    Keeling, V; Jin, H; Ali, I; Ahmad, S [Oklahoma Univ. Health Science Ctr., Oklahoma City, OK (United States)

    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

  19. Gamma Knife Radiosurgery for Acromegaly

    National Research Council Canada - National Science Library

    Rolston, John D; Blevins, Lewis S

    2012-01-01

    .... Stereotactic radiosurgery, and in particular Gamma Knife surgery (GKS), has proven to be an effective noninvasive adjunct to traditional treatments, leading to disease remission in a substantial proportion of patients...

  20. Oligo-recurrence predicts favorable prognosis of brain-only oligometastases in patients with non-small cell lung cancer treated with stereotactic radiosurgery or stereotactic radiotherapy: a multi-institutional study of 61 subjects.

    Science.gov (United States)

    Niibe, Yuzuru; Nishimura, Tetsuo; Inoue, Tetsuya; Karasawa, Katsuyuki; Shioyama, Yoshiyuki; Jingu, Keiichi; Shirato, Hiroki

    2016-08-19

    To investigate the prognostic value of oligo-recurrence in patients with brain-only oligometastases of non-small cell lung cancer (NSCLC) treated with stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT). Patients treated with SRS or SRT for brain-only NSCLC oligometastases in 6 high-volume institutions in Japan between 1996 and 2008 were reviewed. Eligible patients met 1), 2), and 4) or 1), 3), and 4) of the following: 1) NSCLC with 1 to 4 brain metastases on magnetic resonance imaging (MRI) treated with SRS or SRT; 2) control of the primary lesions (thorax) at the time of SRS or SRT for brain metastases (patients meeting this criterion formed the oligo-recurrence group); 3) with SRS or SRT for brain metastases, concomitant treatment for active primary lesions (thorax) with curative surgery or curative stereotactic body radiotherapy (SBRT), or curative chemoradiotherapy (sync-oligometastases group); and 4) Karnofsky performance status (KPS) ≥70. The median overall survival (OS) of all 61 patients was 26 months (95 % CI: 17.5-34.5 months). The 2-year and 5-year overall survival rates were 60.7 and 15.7 %, respectively. Stratified by oligostatus, the sync-oligometastases group achieved a median OS of 18 months (95 % CI: 14.8-21.1 months) and a 5-year OS of 0 %, while the oligo-recurrence group achieved a median OS of 41 months (95 % CI: 27.8-54.2 months) and a 5-year OS of 18.6 %. On multivariate analysis, oligo-recurrence was the only significant independent factor related to a favorable prognosis (hazard ratio: 0.253 (95 % CI: 0.082-0.043) (p = 0.025). The presence of oligo-recurrence can predict a favorable prognosis of brain-only oligometastases in patients with NSCLC treated with SRS or SRT.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zelefsky, Michael J., E-mail: zelefskm@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Greco, Carlo [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Motzer, Robert [Solid Tumor Service, Medical Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Magsanoc, Juan Martin; Pei Xin [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Lovelock, Michael; Mechalakos, Jim [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Zatcky, Joan; Fuks, Zvi; Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-04-01

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

  2. On the use of volumetric-modulated arc therapy for single-fraction thoracic vertebral metastases stereotactic body radiosurgery.

    Science.gov (United States)

    Pokhrel, Damodar; Sood, Sumit; McClinton, Christopher; Shen, Xinglei; Badkul, Rajeev; Jiang, Hongyu; Mallory, Matthew; Mitchell, Mellissa; Wang, Fen; Lominska, Christopher

    2017-01-01

    To retrospectively evaluate quality, efficiency, and delivery accuracy of volumetric-modulated arc therapy (VMAT) plans for single-fraction treatment of thoracic vertebral metastases using image-guided stereotactic body radiosurgery (SBRS) after RTOG 0631 dosimetric compliance criteria. After obtaining credentialing for MD Anderson spine phantom irradiation validation, 10 previously treated patients with thoracic vertebral metastases with noncoplanar hybrid arcs using 1 to 2 3D-conformal partial arcs plus 7 to 9 intensity-modulated radiation therapy beams were retrospectively re-optimized with VMAT using 3 full coplanar arcs. Tumors were located between T2 and T12. Contrast-enhanced T1/T2-weighted magnetic resonance images were coregistered with planning computed tomography and planning target volumes (PTV) were between 14.4 and 230.1cc (median = 38.0cc). Prescription dose was 16Gy in 1 fraction with 6MV beams at Novalis-TX linear accelerator consisting of micro multileaf collimators. Each plan was assessed for target coverage using conformality index, the conformation number, the ratio of the volume receiving 50% of the prescription dose over PTV, R50%, homogeneity index (HI), and PTV_1600 coverage per RTOG 0631 requirements. Organs-at-risk doses were evaluated for maximum doses to spinal cord (D0.03cc, D0.35cc), partial spinal cord (D10%), esophagus (D0.03cc and D5cc), heart (D0.03cc and D15cc), and lung (V5, V10, and maximum dose to 1000cc of lung). Dose delivery efficiency and accuracy of each VMAT-SBRS plan were assessed using quality assurance (QA) plan on MapCHECK device. Total beam-on time was recorded during QA procedure, and a clinical gamma index (2%/2mm and 3%/3mm) was used to compare agreement between planned and measured doses. All 10 VMAT-SBRS plans met RTOG 0631 dosimetric requirements for PTV coverage. The plans demonstrated highly conformal and homogenous coverage of the vertebral PTV with mean HI, conformality index, conformation number, and R50

  3. SU-E-T-128: Applying Failure Modes and Effects Analysis to a Risk-Based Quality Management for Stereotactic Radiosurgery in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, F [comissao nacional de energia nuclear, Rio De Janeiro, RJ (Brazil); Universidade do Estado do Rio de Janeiro, Rio De Janeiro, RJ (Brazil); Almeida, C de [Universidade do Estado do Rio de Janeiro, Rio De Janeiro, RJ (Brazil); Huq, M [University of Pittsburgh Medical Center, Pittsburgh, PA (United States)

    2015-06-15

    Purpose: The goal of the present work was to evaluate the process maps for stereotactic radiosurgery (SRS) treatment at three radiotherapy centers in Brazil and apply the FMEA technique to evaluate similarities and differences, if any, of the hazards and risks associated with these processes. Methods: A team, consisting of professionals from different disciplines and involved in the SRS treatment, was formed at each center. Each team was responsible for the development of the process map, and performance of FMEA and FTA. A facilitator knowledgeable in these techniques led the work at each center. The TG100 recommended scales were used for the evaluation of hazard and severity for each step for the major process “treatment planning”. Results: Hazard index given by the Risk Priority Number (RPN) is found to range from 4–270 for various processes and the severity (S) index is found to range from 1–10. The RPN values > 100 and severity value ≥ 7 were chosen to flag safety improvement interventions. Number of steps with RPN ≥100 were found to be 6, 59 and 45 for the three centers. The corresponding values for S ≥ 7 are 24, 21 and 25 respectively. The range of RPN and S values for each center belong to different process steps and failure modes. Conclusion: These results show that interventions to improve safety is different for each center and it is associated with the skill level of the professional team as well as the technology used to provide radiosurgery treatment. The present study will very likely be a model for implementation of risk-based prospective quality management program for SRS treatment in Brazil where currently there are 28 radiotherapy centers performing SRS. A complete FMEA for SRS for these three radiotherapy centers is currently under development.

  4. Treatment Plan Technique and Quality for Single-Isocenter Stereotactic Ablative Radiotherapy of Multiple Lung Lesions with Volumetric-Modulated Arc Therapy or Intensity-Modulated Radiosurgery.

    Science.gov (United States)

    Quan, Kimmen; Xu, Karen M; Lalonde, Ron; Horne, Zachary D; Bernard, Mark E; McCoy, Chuck; Clump, David A; Burton, Steven A; Heron, Dwight E

    2015-01-01

    The aim of this study is to provide a practical approach to the planning technique and evaluation of plan quality for the multi-lesion, single-isocenter stereotactic ablative radiotherapy (SABR) of the lung. Eleven patients with two or more lung lesions underwent single-isocenter volumetric-modulated arc therapy (VMAT) radiosurgery or IMRS. All plans were normalized to the target maximum dose. For each plan, all targets were treated to the same dose. Plan conformity and dose gradient were maximized with dose-control tuning structures surrounding targets. For comparison, multi-isocenter plans were retrospectively created for four patients. Conformity index (CI), homogeneity index (HI), gradient index (GI), and gradient distance (GD) were calculated for each plan. V5, V10, and V20 of the lung and organs at risk (OARs) were collected. Treatment time and total monitor units (MUs) were also recorded. One patient had four lesions and the remainder had two lesions. Six patients received VMAT and five patients received intensity-modulated radiosurgery (IMRS). For those treated with VMAT, two patients received 3-arc VMAT and four received 2-arc VMAT. For those treated with IMRS, two patients were treated with 10 and 11 beams, respectively, and the rest received 12 beams. Prescription doses ranged from 30 to 54 Gy in three to five fractions. The median prescribed isodose line was 84% (range: 80-86%). The median maximum dose was 57.1 Gy (range: 35.7-65.1 Gy). The mean combined PTV was 49.57 cm(3) (range: 14.90-87.38 cm(3)). For single-isocenter plans, the median CI was 1.15 (range: 0.97-1.53). The median HI was 1.19 (range: 1.16-1.28). The median GI was 4.60 (range: 4.16-7.37). The median maximum radiation dose (Dmax) to total lung was 55.6 Gy (range: 35.7-62.0 Gy). The median mean radiation dose to the lung (Dmean) was 4.2 Gy (range: 1.1-9.3 Gy). The median lung V5 was 18.7% (range: 3.8-41.3%). There was no significant difference in CI, HI, GI, GD, V5, V10

  5. Long-term results of stereotactic radiosurgery to the pituitary gland in Cushing's disease

    Energy Technology Data Exchange (ETDEWEB)

    Degerblad, M.; Raehn, T.; Bergstrand, G.; Thoren, M.

    1986-01-01

    Gamma radiation from /sup 60/Co delivered with stereotactic technique was given to the pituitary gland in 35 patients, aged 18-65 years, with Cushing's disease. The doses were 70-100 Gy in each single irradiation. The size of the sella turcica was normal in the majority of the patients. The observation time was 3-9 years in 29 patiens. Out of them, 14 (48%) obtained clinical remission and normal urinary cortisol after one irradiation. Eight achieved remission after two to four irradiations. In total, 22 out of 29 patients (76%) obtained remission. In 12 of them remission was obtained in 1 year and in another 10 within 3 years. No recurrences were observed. Improvement was seen in 2 patients after one and three irradiations. Bilateral adrenalectomy was performed in 5 patients owing to unsatisfactory effect of irradiation. Pituitary insufficiency with gonadotropin, thyrotropin or cortocotropin failure was demonstrated in 12 of 22 patients in remission. This occurred 4 months to 7 years after the first irradiation. Another 6 patients were followed less than 3 years after the first irradiation. Two obtained remission after the first treatment, whereas the other 4 improved. Stereotactic pituitary irradiation is suggested as a non-invasive therapeutic alternative in Cushing's disease for example in patients with considerable surgical risk or as a supplement to pituitary microsurgery.

  6. SU-E-T-318: The Effect of Patient Positioning Errors On Target Coverage and Cochlear Dose in Stereotactic Radiosurgery Treatment of Acoustic Neuromas

    Energy Technology Data Exchange (ETDEWEB)

    Dellamonica, D.; Luo, G.; Ding, G. [Vanderbilt University, Nashville, TN (United States)

    2014-06-01

    Purpose: Setup errors on the order of millimeters may cause under-dosing of targets and significant changes in dose to critical structures especially when planning with tight margins in stereotactic radiosurgery. This study evaluates the effects of these types of patient positioning uncertainties on planning target volume (PTV) coverage and cochlear dose for stereotactic treatments of acoustic neuromas. Methods: Twelve acoustic neuroma patient treatment plans were retrospectively evaluated in Brainlab iPlan RT Dose 4.1.3. All treatment beams were shaped by HDMLC from a Varian TX machine. Seven patients had planning margins of 2mm, five had 1–1.5mm. Six treatment plans were created for each patient simulating a 1mm setup error in six possible directions: anterior-posterior, lateral, and superiorinferior. The arcs and HDMLC shapes were kept the same for each plan. Change in PTV coverage and mean dose to the cochlea was evaluated for each plan. Results: The average change in PTV coverage for the 72 simulated plans was −1.7% (range: −5 to +1.1%). The largest average change in coverage was observed for shifts in the patient's superior direction (−2.9%). The change in mean cochlear dose was highly dependent upon the direction of the shift. Shifts in the anterior and superior direction resulted in an average increase in dose of 13.5 and 3.8%, respectively, while shifts in the posterior and inferior direction resulted in an average decrease in dose of 17.9 and 10.2%. The average change in dose to the cochlea was 13.9% (range: 1.4 to 48.6%). No difference was observed based on the size of the planning margin. Conclusion: This study indicates that if the positioning uncertainty is kept within 1mm the setup errors may not result in significant under-dosing of the acoustic neuroma target volumes. However, the change in mean cochlear dose is highly dependent upon the direction of the shift.

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

    Energy Technology Data Exchange (ETDEWEB)

    Bisht, R; Kale, S; Gopishankar, N; Rath, G; Julka, P; Agarwal, D; Singh, M; Garg, A; Kumar, P; Thulkar, S; Sharma, B [All India Institute of Medical Sciences, New Delhi (India)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Casamassima, Franco, E-mail: f.casamassima@dfc.unifi.it [Clinical Radiobiological Institute, University of Florence, Florence (Italy); Livi, Lorenzo [Department of Radiation-Oncology, University of Florence, Florence (Italy); Masciullo, Stefano; Menichelli, Claudia; Masi, Laura [Clinical Radiobiological Institute, University of Florence, Florence (Italy); Meattini, Icro [Department of Radiation-Oncology, University of Florence, Florence (Italy); Bonucci, Ivano [Clinical Radiobiological Institute, University of Florence, Florence (Italy); Agresti, Benedetta; Simontacchi, Gabriele [Department of Radiation-Oncology, University of Florence, Florence (Italy); Doro, Raffaela [Clinical Radiobiological Institute, University of Florence, Florence (Italy)

    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.

  9. 伽玛刀治疗鼻咽癌的病理学研究%The pathological changes of nasopharyngeal carcinoma cases treated by stereotactic radiosurgery

    Institute of Scientific and Technical Information of China (English)

    胡正清; 董人禾; 周仲文; 戴嘉中; 潘力; 王滨江

    2000-01-01

    目的:研究伽玛刀(GK)治疗鼻咽癌的病理学变化。方法:选取鼻咽癌放射治疗后肿瘤复发或残留患者15例,病理诊断为鳞状细胞癌,TNM分期为T1~4N0M0,给予GK治疗,靶区包括在50%等剂量曲线之内,周边剂量为20 Gy,治疗前及治疗后1、3、6、12个月分别取鼻咽部癌组织进行病理学研究。结果:①GK治疗后1~3个月,癌组织内出现大量坏死细胞、急性炎症细胞浸润,组织出血;②GK治疗后6~12个月,病灶内有慢性炎症细胞浸润,纤维组织及毛细血管增生,未见肿瘤细胞。结论:GK治疗鼻咽癌的近期病理学变化主要分两期,第1期称坏死期,发生在GK治疗后1~3个月,第2期为吸收期,发生在GK治疗后6~12个月。%Objective:To study the pathological changes of nasopharyngeal carcinoma cases after the treat-ment of stereotactic radiosurgery. Method: 15 cases with recurrent or residual squamous cell carcinoma of na-sopharynx diagnosed as T1~4 N0M0 were selected,which had undergone previous radiotherapy. The patients weretreated by Gamma Knife while the isodose curve was 50%00 and the margin dose was 20 Gy. The nasopharynxbiopsy was performed before the treatment and 1,3,6,12 months after the treatment. The biopsy specimen wastaken to make a pathological examination. Result:①Before the Gamma Knife treatment, carcinoma cell could beseen in the tissue;②1~3 months after the treatment, cell necrosis and acute inflammation cell infiltration couldbe seen in the target ;③6~12 months after the treatment ,infiltration of chronic inflammation cell ,proliferation offibrous tissue and capillary could be found in the target. Conclusion:This research implies that the short-termpathological changes after the treatment of stereotactic radiosurgery can be defined as two phases ..The first phaseoccurs from 1 to 3 months after the treatment called necrosis period. The second phase occurs from 6 to 12

  10. National trends in inpatient admissions following stereotactic radiosurgery and the in-hospital patient outcomes in the United States from 1998 to 2011

    Science.gov (United States)

    Ho, Allen L.; Li, Alexander Y.; Sussman, Eric S.; Pendharkar, Arjun V.; Iyer, Aditya; Thompson, Patricia A.; Tayag, Armine T.; Chang, Steven D.

    2016-01-01

    Purpose This study sought to examine trends in stereotactic radiosurgery (SRS) and in-hospital patient outcomes on a national level by utilizing national administrative data from the Nationwide Inpatient Sample (NIS) database. Methods and materials Using the NIS database, all discharges where patients underwent inpatient SRS were included in our study from 1998 – 2011 as designated by the ICD9-CM procedural codes. Trends in the utilization of primary and adjuvant SRS, in-hospital complications and mortality, and resource utilization were identified and analyzed. Results Our study included over 11,000 hospital discharges following admission for primary SRS or for adjuvant SRS following admission for surgery or other indication. The most popular indication for SRS continues to be treatment of intracranial metastatic disease (36.7%), but expansion to primary CNS lesions and other non-malignant pathology beyond trigeminal neuralgia has occurred over the past decade. Second, inpatient admissions for primary SRS have declined by 65.9% over this same period of time. Finally, as inpatient admissions for SRS become less frequent, the complexity and severity of illness seen in admitted patients has increased over time with an increase in the average comorbidity score from 1.25 in the year 2002 to 2.29 in 2011, and an increase in over-all in-hospital complication rate of 2.8 times over the entire study period. Conclusions As the practice of SRS continues to evolve, we have seen several trends in associated hospital admissions. Overall, the number of inpatient admissions for primary SRS has declined while adjuvant applications have remained stable. Over the same period, there has been associated increase in complication rate, length of stay, and mortality in inpatients. These associations may be explained by an increase in the comorbidity-load of admitted patients as more high-risk patients are selected for admission at inpatient centers while more stable patients are

  11. Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.

    Directory of Open Access Journals (Sweden)

    Guerda Massillon-J L

    Full Text Available This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK and a modified linear accelerator (linac for stereotactic radiosurgery treatments. Measurements were made using Gafchromic film (MD-V2-55, alanine and thermoluminescent (TLD-100 dosimeters and compared with conventional dosimetry systems. Detectors were calibrated in terms of absorbed dose to water in (60Co gamma-ray and 6 MV x-ray reference (10×10 cm(2 fields using an ionization chamber calibrated at a standards laboratory. Absorbed dose to water rate computed with MD-V2-55 was higher than that obtained with the others dosimeters, possibly due to a smaller volume averaging effect. Ratio between the dose-rates determined with each dosimeter and those obtained with the film was evaluated for both treatment modalities. For the LGK, the ratio decreased as the dosimeter size increased and remained constant for collimator diameters larger than 8 mm. The same behaviour was observed for the linac and the ratio increased with field size, independent of the dosimeter used. These behaviours could be explained as an averaging volume effect due to dose gradient and lack of electronic equilibrium. Evaluation of the output factors for the LGK collimators indicated that, even when agreement was observed between Monte Carlo simulation and measurements with different dosimeters, this does not warrant that the absorbed dose to water rate in the field was properly known and thus, investigation of the reference dosimetry should be an important issue. These results indicated that alanine dosimeter provides a high degree of accuracy but cannot be used in fields smaller than 20 mm diameter. Gafchromic film can be considered as a suitable methodology for reference dosimetry. TLD dosimeters are not

  12. Output factor comparison of Monte Carlo and measurement for Varian TrueBeam 6 MV and 10 MV flattening filter-free stereotactic radiosurgery system.

    Science.gov (United States)

    Cheng, Jason Y; Ning, Holly; Arora, Barbara C; Zhuge, Ying; Miller, Robert W

    2016-05-08

    The dose measurements of the small field sizes, such as conical collimators used in stereotactic radiosurgery (SRS), are a significant challenge due to many factors including source occlusion, detector size limitation, and lack of lateral electronic equilibrium. One useful tool in dealing with the small field effect is Monte Carlo (MC) simulation. In this study, we report a comparison of Monte Carlo simulations and measurements of output factors for the Varian SRS system with conical collimators for energies of 6 MV flattening filter-free (6 MV) and 10 MV flattening filter-free (10 MV) on the TrueBeam accelerator. Monte Carlo simulations of Varian's SRS system for 6 MV and 10 MV photon energies with cones sizes of 17.5 mm, 15.0 mm, 12.5 mm, 10.0 mm, 7.5 mm, 5.0 mm, and 4.0 mm were performed using EGSnrc (release V4 2.4.0) codes. Varian's version-2 phase-space files for 6 MV and 10 MV of TrueBeam accelerator were utilized in the Monte Carlo simulations. Two small diode detectors Edge (Sun Nuclear) and Small Field Detector (SFD) (IBA Dosimetry) were applied to measure the output factors. Significant errors may result if detector correction factors are not applied to small field dosimetric measurements. Although it lacked the machine-specific kfclin,fmsrQclin,Qmsr correction factors for diode detectors in this study, correction factors were applied utilizing published studies conducted under similar conditions. For cone diameters greater than or equal to 12.5 mm, the differences between output factors for the Edge detector, SFD detector, and MC simulations are within 3.0% for both energies. For cone diameters below 12.5 mm, output factors differences exhibit greater variations.

  13. Analysis of Circulating Endostatin and Vascular Endothelial Growth Factor in Patients with Pituitary Adenoma Treated by Stereotactic Radiosurgery: A Preliminary Study.

    Science.gov (United States)

    Lee, Kyung-Min; Park, Seong-Hyun; Park, Ki-Su; Hwang, Jeong-Hyun; Hwang, Sung-Kyoo

    2015-10-01

    The purpose of this study was to investigate plasma levels of endostatin and vascular endothelial growth factor (VEGF) in normal subjects and in patients with pituitary adenoma and to evaluate change in these levels following stereotactic radiosurgery (SRS) for pituitary adenoma. Peripheral venous blood was collected from five patients with pituitary adenoma before SRS using Gamma Knife and at the 1 week and 1 month follow-up visits. Plasma endostatin and VEGF levels were measured using commercially available enzyme-linked immunosorbent assay kits. Peripheral blood samples were obtained from 10 healthy volunteers as controls. Mean baseline plasma endostatin level (105.3 ng/mL, range, 97.0-120.2 ng/mL) in patients with pituitary adenoma was higher than that of the healthy controls (86.6 ng/mL, range, 71.3-98.2 ng/mL) (p=0.001). Mean plasma VEGF level was 89.5 pg/mL (range, 24.1-171.8 pg/mL) in patients with pituitary adenoma at baseline and 29.3 pg/mL (range, 9.2-64.3 pg/mL) in the control group (p=0.050). Plasma endostatin level changed to 106.6 ng/mL 1 week after SRS and decreased to 95.9 ng/mL after 1 month. Plasma VEGF level following SRS decreased to 74.1 pg/mL after 1 week and 79.0 pg/mL after 1 month. There was a trend toward decreased plasma endostatin and VEGF concentrations 1 month after SRS compared to baseline levels (p=0.195, p=0.812, respectively). Plasma endostatin and VEGF levels in patients with pituitary adenoma were significantly elevated over controls at baseline, which decreased from baseline to 1 month after SRS for pituitary adenomas.

  14. Long-term safety and efficacy of stereotactic radiosurgery for vestibular schwannomas: evaluation of 440 patients more than 10 years after treatment with Gamma Knife surgery.

    Science.gov (United States)

    Hasegawa, Toshinori; Kida, Yoshihisa; Kato, Takenori; Iizuka, Hiroshi; Kuramitsu, Shunichiro; Yamamoto, Takashi

    2013-03-01

    Object Little is known about long-term outcomes, including tumor control and adverse radiation effects, in patients harboring vestibular schwannomas (VSs) treated with stereotactic radiosurgery > 10 years previously. The aim of this study was to confirm whether Gamma Knife surgery (GKS) for VSs continues to be safe and effective > 10 years after treatment. Methods A total of 440 patients with VS (including neurofibromatosis Type 2) treated with GKS between May 1991 and December 2000 were evaluable. Of these, 347 patients (79%) underwent GKS as an initial treatment and 93 (21%) had undergone prior resection. Three hundred fifty-eight patients (81%) had a solid tumor and 82 (19%) had a cystic tumor. The median tumor volume was 2.8 cm(3) and the median marginal dose was 12.8 Gy. Results The median follow-up period was 12.5 years. The actuarial 5- and ≥ 10-year progression-free survival was 93% and 92%, respectively. No patient developed treatment failure > 10 years after treatment. According to multivariate analysis, significant factors related to worse progression-free survival included brainstem compression with a deviation of the fourth ventricle (p 13 Gy) and 100% in the low marginal dose group (≤ 13 Gy). Ten patients (2.3%) developed delayed cyst formation. One patient alone developed malignant transformation, indicating an incidence of 0.3%. Conclusions In this study GKS was a safe and effective treatment for the majority of patients followed > 10 years after treatment. Special attention should be paid to cyst formation and malignant transformation as late adverse radiation effects, although they appeared to be rare. However, it is necessary to collect further long-term follow-up data before making conclusions about the long-term safety and efficacy of GKS, especially for young patients with VSs.

  15. Total target volume is a better predictor of whole brain dose from gamma stereotactic radiosurgery than the number, shape, or location of the lesions.

    Science.gov (United States)

    Narayanasamy, Ganesh; Smith, Adam; Van Meter, Emily; McGarry, Ronald; Molloy, Janelle A

    2013-09-01

    To assess the hypothesis that the volume of whole brain that receives a certain dose level is primarily dependent on the treated volume rather than on the number, shape, or location of the lesions. This would help a physician validate the suitability of GammaKnife(®) based stereotactic radiosurgery (GKSR) prior to treatment. Simulation studies were performed to establish the hypothesis for both oblong and spherical shaped lesions of various numbers and sizes. Forty patients who underwent GKSR [mean age of 54 years (range 7-80), mean number of lesions of 2.5 (range 1-6), and mean lesion volume of 4.4 cm(3) (range 0.02-22.2 cm(3))] were also studied retrospectively. Following recommendations of QUANTEC, the volume of brain irradiated by the 12 Gy (VB12) isodose line was measured and a power-law based relation is proposed here for estimating VB12 from the known tumor volume and the prescription dose. In the simulation study on oblong, spherical, and multiple lesions, the volume of brain irradiated by 50%, 10%, and 1% of maximum dose was found to have linear, linear, and exponentially increasing dependence on the volume of the treated region, respectively. In the retrospective study on 40 GKSR patients, a similar relationship was found to predict the brain dose with a Spearman correlation coefficient >0.9. In both the studies, the volume of brain irradiated by a certain dose level does not have a statistically significant relationship (p ≥ 0.05) with the number, shape, or position of the lesions. The measured VB12 agrees with calculation to within 1.7%. The results from the simulation and the retrospective clinical studies indicate that the volume of whole brain that receives a certain percentage of the maximum dose is primarily dependent on the treated volume and less on the number, shape, and location of the lesions.

  16. Radiotherapy for brain metastases from renal cell cancer. Should whole-brain radiotherapy be added to stereotactic radiosurgery? Analysis of 88 patients

    Energy Technology Data Exchange (ETDEWEB)

    Fokas, Emmanouil; Henzel, Martin; Engenhart-Cabillic, Rita [Dept. of Radiotherapy and Radiation Oncology, Philipps Univ. Marburg (Germany); Hamm, Klaus; Surber, Gunnar; Kleinert, Gabriele [Dept. for Stereotactic Neurosurgery and Radiosurgery, HELIOS Klinikum Erfurt (Germany)

    2010-04-15

    Purpose: To evaluate the role of stereotactic radiosurgery (SRS) and whole-brain radiotherapy (WBRT) for the treatment of brain metastases in patients with renal cell cancer (RCC). Patients and methods: 88 patients were treated with either SRS (n = 51) or SRS + WBRT (n = 17) for one to three lesions, or with WBRT (n = 20) for more than three brain metastases. Overall survival (OS), intracerebral control (IC) and local control (LC) were retrospectively analyzed. Six potential prognostic factors were assessed: age, gender, number of brain metastases, extracerebral metastases, recursive partitioning analysis (RPA) class, and interval from tumor diagnosis to irradiation. Results: The median times for OS, IC, and LC from the time of diagnosis were 11, 9, and 10 months. The median OS times for SRS, SRS + WBRT, and WBRT were 12, 16, and 2 months. Addition of WBRT to the SRS improved IC (p = 0.032) but not OS (p = 0.703). On multivariate analyses, improved OS was associated with the absence of extracerebral metastases (p < 0.001) and RPA class (p = 0.04), and IC with treatment (p = 0.019). SRS provided a 1-year, 2-year, and 3-year LC probability of 81%, 78%, and 55%, respectively. No association between LC and any of the potential prognostic factors was observed. The results of the subgroup analyses, regarding treatment modality, were similar to the entire cohort, particularly for RPA class I patients. Conclusion: Addition of WBRT to SRS offers better IC and should be considered for RCC patients with one to three brain metastases, especially in RPA class I group. SRS offers excellent LC rates, while WBRT should be reserved for patients with multiple metastases and poor prognosis. (orig.)

  17. SU-E-T-374: Evaluation and Verification of Dose Calculation Accuracy with Different Dose Grid Sizes for Intracranial Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Han, C; Schultheiss, T [City of Hope National Medical Center, Duarte, CA (United States)

    2015-06-15

    Purpose: In this study, we aim to evaluate the effect of dose grid size on the accuracy of calculated dose for small lesions in intracranial stereotactic radiosurgery (SRS), and to verify dose calculation accuracy with radiochromic film dosimetry. Methods: 15 intracranial lesions from previous SRS patients were retrospectively selected for this study. The planning target volume (PTV) ranged from 0.17 to 2.3 cm{sup 3}. A commercial treatment planning system was used to generate SRS plans using the volumetric modulated arc therapy (VMAT) technique using two arc fields. Two convolution-superposition-based dose calculation algorithms (Anisotropic Analytical Algorithm and Acuros XB algorithm) were used to calculate volume dose distribution with dose grid size ranging from 1 mm to 3 mm with 0.5 mm step size. First, while the plan monitor units (MU) were kept constant, PTV dose variations were analyzed. Second, with 95% of the PTV covered by the prescription dose, variations of the plan MUs as a function of dose grid size were analyzed. Radiochomic films were used to compare the delivered dose and profile with the calculated dose distribution with different dose grid sizes. Results: The dose to the PTV, in terms of the mean dose, maximum, and minimum dose, showed steady decrease with increasing dose grid size using both algorithms. With 95% of the PTV covered by the prescription dose, the total MU increased with increasing dose grid size in most of the plans. Radiochromic film measurements showed better agreement with dose distributions calculated with 1-mm dose grid size. Conclusion: Dose grid size has significant impact on calculated dose distribution in intracranial SRS treatment planning with small target volumes. Using the default dose grid size could lead to under-estimation of delivered dose. A small dose grid size should be used to ensure calculation accuracy and agreement with QA measurements.

  18. Testing different brain metastasis grading systems in stereotactic radiosurgery: Radiation Therapy Oncology Group's RPA, SIR, BSBM, GPA, and modified RPA.

    Science.gov (United States)

    Serizawa, Toru; Higuchi, Yoshinori; Nagano, Osamu; Hirai, Tatsuo; Ono, Junichi; Saeki, Naokatsu; Miyakawa, Akifumi

    2012-12-01

    The authors conducted validity testing of the 5 major reported indices for radiosurgically treated brain metastases- the original Radiation Therapy Oncology Group's Recursive Partitioning Analysis (RPA), the Score Index for Radiosurgery in Brain Metastases (SIR), the Basic Score for Brain Metastases (BSBM), the Graded Prognostic Assessment (GPA), and the subclassification of RPA Class II proposed by Yamamoto-in nearly 2500 cases treated with Gamma Knife surgery (GKS), focusing on the preservation of neurological function as well as the traditional endpoint of overall survival. The authors analyzed data from 2445 cases treated with GKS by the first author (T.S.), the primary surgeon. The patient group consisted of 1716 patients treated between January 1998 and March 2008 (the Chiba series) and 729 patients treated between April 2008 and December 2011 (the Tokyo series). The interval from the date of GKS until the date of the patient's death (overall survival) and impaired activities of daily living (qualitative survival) were calculated using the Kaplan-Meier method, while the absolute risk for two adjacent classes of each grading system and both hazard ratios and 95% confidence intervals were estimated using the Cox proportional hazards model. For overall survival, there were highly statistically significant differences between each two adjacent patient groups characterized by class or score (all p values GPA Scores 3.5-4.0 and 3.0. The SIR showed the best statistical results for predicting preservation of neurological function. Although no other grading systems yielded statistically significant differences in qualitative survival, the BSBM and the modified RPA appeared to be better than the original RPA and GPA. The modified RPA subclassification, proposed by Yamamoto, is well balanced in scoring simplicity with respect to case number distribution and statistical results for overall survival. However, a new or revised grading system is necessary for predicting

  19. Stereotactic Ablative Radiosurgery for Locally-Advanced or Recurrent Skull Base Malignancies with Prior External Beam Radiation Therapy

    Directory of Open Access Journals (Sweden)

    Karen Mann Xu

    2015-03-01

    Full Text Available Purpose: Stereotactic ablative radiotherapy (SABR is an attractive modality to treat malignancies invading the skull base as it can deliver a highly conformal dose with minimal toxicity. However, variation exists in the prescribed dose and fractionation. The purpose of our study is to examine the local control, survival and toxicities in SABR for the treatment of malignant skull base tumors. Methods and Materials: A total of 31 patients and 40 locally-advanced or recurrent head and neck malignancies involving the skull base treated with a common SABR regimen which delivers a radiation dose of 44 Gy in 5 fractions from January 1st, 2004 to December 31st, 2013 were retrospectively reviewed. The local control rate (LC, progression-free survival rate (PFS, overall survival rate (OS and toxicities were reported.Results: The median follow-up time of all patients was 11.4 months (range: 0.6-67.2 months. The median tumor volume was 27 cm3 (range: 2.4-205 cm3. All patients received prior EBRT with a median radiation dose of 64 Gy (range: 24-75.6 Gy delivered in 12 to 42 fractions. 20 patients had surgeries prior to SABR. 19 patients received chemotherapy. Specifically, 8 patients received concurrent cetuximab (ErbituxTM with SABR. The median time-to-progression (TTP was 3.3 months (range: 0-16.9 months. For the 29 patients (93.5% who died, the median time from the end of first SABR to death was 10.3 months (range: 0.5-41.4 months. The estimated 1-year overall survival (OS rate was 35%. The estimated 2-year OS rate was 12%. Treatment was well-tolerated without grade 4 or 5 treatment-related toxicities.Conclusions: SABR has been shown to achieve low toxicities in locally-advanced or recurrent, previously irradiated head and neck malignancies invading the skull base.

  20. 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

    OpenAIRE

    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 

  1. Can an alternative backround-corrected [18F] fluorodeoxyglucose (FDG standard uptake value (SUV be used for monitoring tumor local control following lung cancer stereotactic body radiosurgery?

    Directory of Open Access Journals (Sweden)

    Charles Shang

    2014-08-01

    assessing local tumor control after lung SBRT......................................................Cite this article as: Shang CY, Kasper ME, Kathriarachchi V, Benda RK, Kleinman JH, Cole J, Williams TR. Can an alternative backround-corrected [18F] fluorodeoxyglucose (FDG standard uptake value (SUV be used for monitoring tumor local control following lung cancer stereotactic body radiosurgery? Int J Cancer Ther Oncol 2014; 2(4:020317.DOI: 10.14319/ijcto.0203.17

  2. Treatment plan technique and quality for single-isocenter stereotactic ablative radiotherapy of multiple lung lesions with volumetric modulated arc therapy or intensity-modulated radiosurgery

    Directory of Open Access Journals (Sweden)

    Kimmen eQuan

    2015-10-01

    Full Text Available Purpose: The aim is to provide a practical approach to the planning technique and evaluation of plan quality for the multi-lesion, single-isocenter stereotactic ablative radiotherapy (SABR of the lung. Methods and Materials: Eleven patients with 2 or more lung lesions underwent single-isocenter VMAT radiosurgery or IMRS. All plans were normalized to the target maximum dose. For each plan, all targets were treated to the same dose. Plan conformity and dose gradient were maximized with dose control tuning structures surrounding targets. For comparison, multi-isocenter plans were retrospectively created for 4 patients. Conformity index (CI, homogeneity index (HI, gradient index (GI and gradient distance (GD were calculated for each plan. V5, V10, and V20 of the lung and organs at risk (OARs were collected. Treatment time and total monitor units (MUs were also recorded. Results: One patient had 4 lesions and the remainder had 2 lesions. Six patients received VMAT and 5 patients received IMRS. For those treated with VMAT, two patients received 3-arc VMAT and four received 2-arc VMAT. For those treated with IMRS, two patients were treated with 10 and 11 beams, respectively, and the rest received 12 beams. Prescription doses ranged from 30 to 54 Gy in 3 to 5 fractions. The median prescribed isodose line was 84% (range: 80-86%. The median maximum dose was 57.1 Gy (range: 35.7-65.1 Gy. The mean combined PTV was 49.57 cm3 (range: 14.90 - 87.38 cm3. For single-isocenter plans, the median CI was 1.15 (range: 0.97-1.53. The median HI was 1.19 (range: 1.16-1.28. The median GI was 4.60 (range: 4.16-7.37. The median maximum radiation dose (Dmax to total lung was 55.6 Gy (range: 35.7-62.0 Gy. The median mean radiation dose to the lung (Dmean was 4.2 Gy (range: 1.1-9.3 Gy. The median lung V5 was 18.7% (range: 3.8-41.3%. There was no significant difference in CI, HI, GI, GD, V5, V10 and V20 (lung, heart, trachea, esophagus, and spinal cord between single

  3. Hippocampal dose from stereotactic radiosurgery for 4 to 10 brain metastases: Risk factors, feasibility of dose reduction via re-optimization, and patient outcomes.

    Science.gov (United States)

    Birer, Samuel R; Olson, Adam C; Adamson, Justus; Hood, Rodney; Susen, Matthew; Kim, Grace; Salama, Joseph K; Kirkpatrick, John P

    2017-07-28

    This study aimed to report hippocampal dose from single-fraction stereotactic radiosurgery (SRS) for 4 to 10 brain metastases and determine feasibility of hippocampal-sparing SRS. Patients with 4 to 10 brain metastases receiving single-isocenter, multi-target single-fraction SRS were identified. Hippocampi were contoured using the Radiation Therapy Oncology Group (RTOG) 0933 atlas. RTOG 0933 dose constraints were converted to a biologically effective dose using an alpha/beta of 2 (D100 421 cGy, Dmax 665 cGy). Number of metastases, total target volume, prescribed dose, and distance of nearest metastasis (dmin) were analyzed as risk factors for exceeding hippocampal constraints. If hippocampi exceeded constraints, the SRS plan was re-optimized. Key dosimetric parameters were compared between original and re-optimized plans. To determine if a single target can exceed constraints, all targets but the closest metastasis were removed from the plan, and dosimetry was compared. Forty plans were identified. Fifteen hippocampi (19%) exceeded constraints in 12 SRS plans. Hippocampal sparing was achieved in 10 of 12 replanned cases (83%). Risk factors associated with exceeding hippocampal constraints were decreasing dmin (24.0 vs 8.0 mm, p = 0.002; odds ratio [OR] 1.14, 95% confidence interval [CI] 1.04 to 1.26) and total target volume (5.46 cm(3)vs 1.98 cm(3), p = 0.03; OR 1.14, 95% CI 1.00 to 1.32). There was no difference in exceeding constraints for 4 to 5 vs 6 to 10 metastases (27% vs 21%, p = 0.409) or prescribed dose (18 Gy, p = 0.58). For re-optimized plans, there were no significant differences in planning target volume (PTV) coverage (99.6% vs 99.0%, p = 0.17) or conformality index (1.47 vs 1.4, p = 0.78). Six (50%) plans exceeded constraints with a single target. A substantial minority of hippocampi receive high radiation dose from SRS for 4 to 10 brain metastases. Decreasing distance of the closest metastasis and total target volume

  4. SU-E-J-217: Multiparametric MR Imaging of Cranial Tumors On a Dedicated 1.0T MR Simulator Prior to Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Wen, N; Glide-Hurst, C; Liu, M; Hearshen, D; Brown, S; Siddiqui, S; Chetty, I [Henry Ford Health System, Detroit, MI (United States)

    2015-06-15

    Purpose: Quantitative magnetic resonance imaging (MRI) of cranial lesions prior to stereotactic radiosurgery (SRS) may improve treatment planning and provide potential prognostic value. The practicality and logistics of acquiring advanced multiparametric MRI sequences to measure vascular and cellular properties of cerebral tumors are explored on a 1.0 Tesla MR Simulator. Methods: MR simulation was performed immediately following routine CT simulation on a 1T MR Simulator. MR sequences used were in the order they were performed: T2-Weighted Turbo Spin Echo (T2W-TSE), T2 FLAIR, Diffusion-weighted (DWI, b = 0, 800 to generate an apparent diffusion coefficient (ADC) map), 3D T1-Weighted Fast Field Echo (T1W-FFE), Dynamic Contrast Enhanced (DCE) and Post Gadolinium Contrast Enhanced 3D T1W-FFE images. T1 pre-contrast values was generated by acquiring six different flip angles. The arterial input function was derived from arterial pixels in the perfusion images selected manually. The extended Tofts model was used to generate the permeability maps. Routine MRI scans took about 30 minutes to complete; the additional scans added 12 minutes. Results: To date, seven patients with cerebral tumors have been imaged and tumor physiology characterized. For example, on a glioblastoma patient, the volume contoured on T1 Gd images, ADC map and the pharmacokinetic map (Ktrans) were 1.9, 1.4, and 1.5 cc respectively with strong spatial correlation. The mean ADC value of the entire volume was 1141 μm2/s while the value in the white matter was 811 μm2/s. The mean value of Ktrans was 0.02 min-1 in the tumor volume and 0.00 in the normal white matter. Conclusion: Our initial results suggest that multiparametric MRI sequences may provide a more quantitative evaluation of vascular and tumor properties. Implementing functional imaging during MR-SIM may be particularly beneficial in assessing tumor extent, differentiating radiation necrosis from tumor recurrence, and establishing reliable

  5. Phase 3 Trials of Stereotactic Radiosurgery With or Without Whole-Brain Radiation Therapy for 1 to 4 Brain Metastases: Individual Patient Data Meta-Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sahgal, Arjun, E-mail: arjun.sahgal@sunnybrook.ca [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Aoyama, Hidefumi [Department of Radiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata (Japan); Kocher, Martin [Department of Radiation Oncology, University of Cologne, Cologne (Germany); Neupane, Binod [Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario (Canada); Collette, Sandra [Statistics Department, European Organisation for Research and Treatment of Cancer, Brussels (Belgium); Tago, Masao [Department of Radiology, Teikyo University Mizonokuchi Hospital, Kanagawa (Japan); Shaw, Prakesh [Department of Pediatrics, Mount Sinai Hospital, Institute of Health Policy Management and Evaluation, University of Toronto, Ontario (Canada); Beyene, Joseph [Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario (Canada); Chang, Eric L. [Department of Radiation Oncology, University of Southern California, Los Angeles, California (United States); Department of Radiation Oncology, MD Anderson Cancer Center, Houston, Texas (United States)

    2015-03-15

    Purpose: To perform an individual patient data (IPD) meta-analysis of randomized controlled trials evaluating stereotactic radiosurgery (SRS) with or without whole-brain radiation therapy (WBRT) for patients presenting with 1 to 4 brain metastases. Method and Materials: Three trials were identified through a literature search, and IPD were obtained. Outcomes of interest were survival, local failure, and distant brain failure. The treatment effect was estimated after adjustments for age, recursive partitioning analysis (RPA) score, number of brain metastases, and treatment arm. Results: A total of 364 of the pooled 389 patients met eligibility criteria, of whom 51% were treated with SRS alone and 49% were treated with SRS plus WBRT. For survival, age was a significant effect modifier (P=.04) favoring SRS alone in patients ≤50 years of age, and no significant differences were observed in older patients. Hazard ratios (HRs) for patients 35, 40, 45, and 50 years of age were 0.46 (95% confidence interval [CI] = 0.24-0.90), 0.52 (95% CI = 0.29-0.92), 0.58 (95% CI = 0.35-0.95), and 0.64 (95% CI = 0.42-0.99), respectively. Patients with a single metastasis had significantly better survival than those who had 2 to 4 metastases. For distant brain failure, age was a significant effect modifier (P=.043), with similar rates in the 2 arms for patients ≤50 of age; otherwise, the risk was reduced with WBRT for patients >50 years of age. Patients with a single metastasis also had a significantly lower risk of distant brain failure than patients who had 2 to 4 metastases. Local control significantly favored additional WBRT in all age groups. Conclusions: For patients ≤50 years of age, SRS alone favored survival, in addition, the initial omission of WBRT did not impact distant brain relapse rates. SRS alone may be the preferred treatment for this age group.

  6. Development of a frameless stereotactic radiosurgery system based on real-time 6D position monitoring and adaptive head motion compensation

    Science.gov (United States)

    Wiersma, Rodney D.; Wen, Zhifei; Sadinski, Meredith; Farrey, Karl; Yenice, Kamil M.

    2010-01-01

    Stereotactic radiosurgery delivers radiation with great spatial accuracy. To achieve sub-millimeter accuracy for intracranial SRS, a head ring is rigidly fixated to the skull to create a fixed reference. For some patients, the invasiveness of the ring can be highly uncomfortable and not well tolerated. In addition, placing and removing the ring requires special expertise from a neurosurgeon, and patient setup time for SRS can often be long. To reduce the invasiveness, hardware limitations and setup time, we are developing a system for performing accurate head positioning without the use of a head ring. The proposed method uses real-time 6D optical position feedback for turning on and off the treatment beam (gating) and guiding a motor-controlled 3D head motion compensation stage. The setup consists of a central control computer, an optical patient motion tracking system and a 3D motion compensation stage attached to the front of the LINAC couch. A styrofoam head cast was custom-built for patient support and was mounted on the compensation stage. The motion feedback of the markers was processed by the control computer, and the resulting motion of the target was calculated using a rigid body model. If the target deviated beyond a preset position of 0.2 mm, an automatic position correction was performed with stepper motors to adjust the head position via the couch mount motion platform. In the event the target deviated more than 1 mm, a safety relay switch was activated and the treatment beam was turned off. The feasibility of the concept was tested using five healthy volunteers. Head motion data were acquired with and without the use of motion compensation over treatment times of 15 min. On average, test subjects exceeded the 0.5 mm tolerance 86% of the time and the 1.0 mm tolerance 45% of the time without motion correction. With correction, this percentage was reduced to 5% and 2% for the 0.5 mm and 1.0 mm tolerances, respectively.

  7. Development of a frameless stereotactic radiosurgery system based on real-time 6D position monitoring and adaptive head motion compensation

    Energy Technology Data Exchange (ETDEWEB)

    Wiersma, Rodney D; Wen Zhifei; Sadinski, Meredith; Farrey, Karl; Yenice, Kamil M [Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL 60637 (United States)], E-mail: rwiersma@uchicago.edu

    2010-01-21

    Stereotactic radiosurgery delivers radiation with great spatial accuracy. To achieve sub-millimeter accuracy for intracranial SRS, a head ring is rigidly fixated to the skull to create a fixed reference. For some patients, the invasiveness of the ring can be highly uncomfortable and not well tolerated. In addition, placing and removing the ring requires special expertise from a neurosurgeon, and patient setup time for SRS can often be long. To reduce the invasiveness, hardware limitations and setup time, we are developing a system for performing accurate head positioning without the use of a head ring. The proposed method uses real-time 6D optical position feedback for turning on and off the treatment beam (gating) and guiding a motor-controlled 3D head motion compensation stage. The setup consists of a central control computer, an optical patient motion tracking system and a 3D motion compensation stage attached to the front of the LINAC couch. A styrofoam head cast was custom-built for patient support and was mounted on the compensation stage. The motion feedback of the markers was processed by the control computer, and the resulting motion of the target was calculated using a rigid body model. If the target deviated beyond a preset position of 0.2 mm, an automatic position correction was performed with stepper motors to adjust the head position via the couch mount motion platform. In the event the target deviated more than 1 mm, a safety relay switch was activated and the treatment beam was turned off. The feasibility of the concept was tested using five healthy volunteers. Head motion data were acquired with and without the use of motion compensation over treatment times of 15 min. On average, test subjects exceeded the 0.5 mm tolerance 86% of the time and the 1.0 mm tolerance 45% of the time without motion correction. With correction, this percentage was reduced to 5% and 2% for the 0.5 mm and 1.0 mm tolerances, respectively.

  8. Analysis of volumetric response of pituitary adenomas receiving adjuvant CyberKnife stereotactic radiosurgery with the application of an exponential fitting model

    Science.gov (United States)

    Yu, Yi-Lin; Yang, Yun-Ju; Lin, Chin; Hsieh, Chih-Chuan; Li, Chiao-Zhu; Feng, Shao-Wei; Tang, Chi-Tun; Chung, Tzu-Tsao; Ma, Hsin-I; Chen, Yuan-Hao; Ju, Da-Tong; Hueng, Dueng-Yuan

    2017-01-01

    Abstract Tumor control rates of pituitary adenomas (PAs) receiving adjuvant CyberKnife stereotactic radiosurgery (CK SRS) are high. However, there is currently no uniform way to estimate the time course of the disease. The aim of this study was to analyze the volumetric responses of PAs after CK SRS and investigate the application of an exponential decay model in calculating an accurate time course and estimation of the eventual outcome. A retrospective review of 34 patients with PAs who received adjuvant CK SRS between 2006 and 2013 was performed. Tumor volume was calculated using the planimetric method. The percent change in tumor volume and tumor volume rate of change were compared at median 4-, 10-, 20-, and 36-month intervals. Tumor responses were classified as: progression for >15% volume increase, regression for ≤15% decrease, and stabilization for ±15% of the baseline volume at the time of last follow-up. For each patient, the volumetric change versus time was fitted with an exponential model. The overall tumor control rate was 94.1% in the 36-month (range 18–87 months) follow-up period (mean volume change of −43.3%). Volume regression (mean decrease of −50.5%) was demonstrated in 27 (79%) patients, tumor stabilization (mean change of −3.7%) in 5 (15%) patients, and tumor progression (mean increase of 28.1%) in 2 (6%) patients (P = 0.001). Tumors that eventually regressed or stabilized had a temporary volume increase of 1.07% and 41.5% at 4 months after CK SRS, respectively (P = 0.017). The tumor volume estimated using the exponential fitting equation demonstrated high positive correlation with the actual volume calculated by magnetic resonance imaging (MRI) as tested by Pearson correlation coefficient (0.9). Transient progression of PAs post-CK SRS was seen in 62.5% of the patients receiving CK SRS, and it was not predictive of eventual volume regression or progression. A three-point exponential model is of potential predictive value

  9. Stereotactic LINAC radiosurgery for the treatment of typical intracranial meningiomas. Efficacy and safety after a follow-up of over 12 years

    Energy Technology Data Exchange (ETDEWEB)

    El-Khatib, Mustafa [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); University Hospital of Bonn, Department of Neurosurgery, Bonn (Germany); El Majdoub, Faycal; Hunsche, Stefan; Maarouf, Mohammad [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); University of Witten/Herdecke, Department of Stereotaxy and Functional Neurosurgery, Center of Neurosurgery, Cologne-Merheim Medical Center (CMMC), Cologne (Germany); Hoevels, Mauritius [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); Kocher, Martin [University Hospital of Cologne, Department of Radiation Oncology, Cologne (Germany); Sturm, Volker [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); University Hospital of Wurzburg, Department of Neurosurgery, Wuerzburg (Germany)

    2015-12-15

    The efficacy and safety of stereotactic radiosurgery (SRS) for treatment of intracranial meningiomas has been demonstrated in numerous studies with short- and intermediate-term follow-up. In this retrospective single-center study, we present long-term outcomes of SRS performed with a linear accelerator (LINAC) for typical intracranial meningiomas. Between August 1990 and December 2007, 148 patients with 168 typical intracranial meningiomas were treated with stereotactic LINAC-SRS, either as primary treatment or after microsurgical resection. A median tumor surface dose of 12 Gy (range 7-20 Gy) and a median maximum dose of 24.1 Gy (range 11.3-58.6 Gy) was applied. The median target volume was 4.7 ml (range 0.2-32.8 ml, SD ± 4.8 ml). Overall mean radiological follow-up was 12.6 years. Tumor shrinkage was seen in 75 (44.6 %) and stable disease in 85 (50.6 %) cases. Eight of 168 meningiomas (4.8 %) showed local tumor progression. The tumor control rate (TCR) after 5, 10, and 15 years was 93.6 % at each time point, and the progression-free survival (PSF) rates were 92, 89, and 89 %, respectively. The neurological symptoms existing prior to LINAC-SRS improved in 77 patients (59.7 %), remained unchanged in 42 (32.6 %), and deteriorated in 10 (7.8 %) patients. Our study emphasizes the efficacy of LINAC-SRS for de novo, residual and recurrent typical intracranial meningiomas. A high long-term local TCR with a low morbidity rate could be achieved. LINAC-SRS should thus be considered as a primary treatment option, as one arm of a combined treatment approach for incompletely resected meningiomas, or as a salvage therapy for recurrences. (orig.) [German] Die Wirksamkeit und Sicherheit der stereotaktischen Radiochirurgie (SRS) zur Behandlung intrakranieller Meningeome konnten in vielen Studien nach einer kurzen oder mittleren Nachbeobachtungszeit gezeigt werden. In der folgenden retrospektiven Studie eines Zentrums werden Langzeitergebnisse der SRS unter Verwendung eines

  10. Radiosurgery of acoustic neurinomas

    Energy Technology Data Exchange (ETDEWEB)

    Flickinger, J.C.; Lunsford, L.D.; Coffey, R.J.; Linskey, M.E.; Bissonette, D.J.; Maitz, A.H.; Kondziolka, D. (Univ. of Pittsburgh School of Medicine, PA (USA))

    1991-01-15

    Eighty-five patients with acoustic neurinomas underwent stereotactic radiosurgery with the gamma unit at the University of Pittsburgh (Pittsburgh, PA) during its first 30 months of operation. Neuroimaging studies performed in 40 patients with more than 1 year follow-up showed that tumors were smaller in 22 (55%), unchanged in 17 (43%), and larger in one (2%). The 2-year actuarial rates for preservation of useful hearing and any hearing were 46% and 62%, respectively. Previously undetected neuropathies of the trigeminal (n = 12) and facial nerves (n = 14) occurred 1 week to 1 year after radiosurgery (median, 7 and 6 months, respectively), and improved at median intervals of 13 and 8 months, respectively, after onset. Hearing loss was significantly associated with increasing average tumor diameter (P = 0.04). No deterioration of any cranial nerve function has yet developed in seven patients with average tumor diameters less than 10 mm. Radiosurgery is an important treatment alternative for selected acoustic neurinoma patients.

  11. Stereotactic Radiosurgery and Stereotactic Body Radiotherapy (SBRT)

    Science.gov (United States)

    ... is considered a success. In some tumors, like acoustic neuromas, a temporary enlargement may be observed following ... spots on the back of your head. A box-shaped head frame will be attached to your ...

  12. IMRT with Stereotactic Body Radiotherapy Boost for High Risk Malignant Salivary Gland Malignancies : A Case Series

    Directory of Open Access Journals (Sweden)

    Sana D Karam

    2014-10-01

    Full Text Available Patients with high risk salivary gland malignancies are at increased risk of local failure. We present our institutional experience with dose escalation using hypofractionated Stereotactic Body Radiotherapy (SBRT in a subset of this rare disease. Over the course of 9 years, 10 patients presenting with skull base invasion, gross disease with one or more adverse features, or those treated with adjuvant radiation with three or more pathologic features were treated with intensity modulated radiation therapy followed by hypofractionated SBRT boost. Patients presented with variable tumor histologies, and in all but one, the tumors were classified as poorly differentiated high grade. Four patients had gross disease, 3 had gross residual disease, 3 had skull base invasion, and 2 patients had rapidly recurrent disease (≤ 6 months that had been previously treated with surgical resection. The median Stereotactic Radiosurgery boost dose was 17.5 Gy (range 10-30 Gy given in a median of 5 fractions (range 3-6 fractions for a total median cumulative dose of 81.2 Gy (range 73.2-95.6 Gy. The majority of the patients received platinum based concurrent chemotherapy with their radiation. At a median follow-up of 32 months (range 12-120 for all patients and 43 months for surviving patients (range 12-120, actuarial 3-year locoregional control, distant control, progression free survival, and overall survival were 88%, 81%, 68%, and 79%, respectively. Only one patient failed locally and two failed distantly. Serious late toxicity included graft ulceration in 1 patient and osteoradionecrosis in another patient, both of which underwent surgical reconstruction. Six patients developed fibrosis. In a subset of patients with salivary gland malignancies with skull base invasion, gross disease, or those treated adjuvantly with three or more adverse pathologic features, hypofractionated SBRT boost to Intensity Modulated Radiotherapy yields good local control rates and

  13. Stereotactic radiotherapy of meningiomas. Symptomatology, acute and late toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Henzel, M.; Gross, M.W.; Failing, T.; Strassmann, G.; Engenhart-Cabillic, R. [Dept. of Radiation Oncology, Univ. of Gisssen (Germany); Dept. of Radiation Oncology, Marburg Univ. (Germany); Hamm, K.; Surber, G.; Kleinert, G. [Dept. of Stereotactic Neurosurgery and Radiosurgery, Helios Klinikum Erfurt (Germany)

    2006-07-15

    Background and purpose: stereotactic radiosurgery (SRS) is well established in the treatment of skull base meningiomas, but this therapy approach is limited to small tumors only. The fractionated stereotactic radiotherapy (SRT) offers an alternative treatment option. This study aims at local control, symptomatology, and toxicity. Patients and methods: between 1997-2003, 224 patients were treated with SRT (n= 183), hypofractionated SRT (n = 30), and SRS (n = 11). 95/224 were treated with SRT/SRS alone. 129/224 patients underwent previous operations. Freedom from progression and overall survival, toxicity, and symptomatology were evaluated systematically. Additionally, tumor volume (TV) shrinkage was analyzed three-dimensionally within the planning system. Results: the median follow-up was 36 months (range, 12-100 months). Overall survival and freedom from progression for 5 years were 92.9% and 96.9%. Quantitative TV reduction was 26.2% and 30.3% 12 and 18 months after SRT/SRS (p < 0.0001). 95.9% of the patients improved their symptoms or were stable. Clinically significant acute toxicity (CTC III ) was rarely seen (2.5%). Clinically significant late morbidity (III -IV ) or new cranial nerve palsies did not occur. Conclusion: SRT offers an additional treatment option of high efficacy with only few side effects. In the case of large tumor size (> 4 ml) and adjacent critical structures (< 2 mm), SRT is highly recommended. (orig.)

  14. Intracranial radiosurgery in the Netherlands. A planning comparison of available systems with regard to physical aspects and workload.

    NARCIS (Netherlands)

    Schoonbeek, A.; Monshouwer, R.; Hanssens, P.; Raaijmakers, E.; Nowak, P.; Marijnissen, J.P.; Lagerwaard, F.J.; Cuijpers, J.P.; Vonk, E.J.; Maazen, R.W.M. van der

    2010-01-01

    Different planning and treatment systems for intracranial stereotactic radiosurgery available in the Netherlands are compared. The systems for intracranial radiosurgery include: Gamma Knife, Cyberknife, Novalis, and Tomotherapy. Electronic data of 5 patients was transferred to all participating

  15. Intracranial radiosurgery in the Netherlands. A planning comparison of available systems with regard to physical aspects and workload.

    NARCIS (Netherlands)

    Schoonbeek, A.; Monshouwer, R.; Hanssens, P.; Raaijmakers, E.; Nowak, P.; Marijnissen, J.P.; Lagerwaard, F.J.; Cuijpers, J.P.; Vonk, E.J.; Maazen, R.W.M. van der

    2010-01-01

    Different planning and treatment systems for intracranial stereotactic radiosurgery available in the Netherlands are compared. The systems for intracranial radiosurgery include: Gamma Knife, Cyberknife, Novalis, and Tomotherapy. Electronic data of 5 patients was transferred to all participating cent

  16. Updates in outcomes of stereotactic radiation therapy in acromegaly.

    Science.gov (United States)

    Gheorghiu, Monica Livia

    2017-02-01

    Purpose Treatment of acromegaly has undergone important progress in the last 20 years mainly due to the development of new medical options and advances in surgical techniques. Pituitary surgery is usually first-line therapy, and medical treatment is indicated for persistent disease, while radiation (RT) is often used as third-line therapy. The benefits of RT (tumor volume control and decreased hormonal secretion) are hampered by the long latency of the effect and the high risk of adverse effects. Stereotactic RT methods have been developed with the aim to provide more precise targeting of the tumor with better control of the radiation dose received by the adjacent brain structures. The purpose of this review is to present the updates in the efficacy and safety of pituitary RT in acromegalic patients, with an emphasis on the new stereotactic radiation techniques. Methods A systematic review was performed using PubMed and articles/abstracts and reviews detailing RT in acromegaly from 2000 to 2016 were included. Results Stereotactic radiosurgery and fractionated stereotactic RT (FSRT) for patients with persistent active acromegaly after surgery and/or during medical therapy provide comparable high rates of tumor control, i.e. stable or decrease in size of the tumor in 93-100% of patients at 5-10 years and endocrinological remission in 40-60% of patients at 5 years. Hypofractionated RT is an optimal option for tumors located near the optic structures, due to its lower toxicity for the optic nerves compared to single-dose radiosurgery. The rate of new hypopituitarism varies from 10 to 50% at 5 years and increases with the duration of follow-up. The risk for other radiation-induced complications is usually low (0-5% for new visual deficits, cranial nerves damage or brain radionecrosis and 0-1% for secondary brain tumors) and risk of stroke may be higher in FSRT. Conclusion Although the use of radiotherapy in patients with acromegaly has decreased with advances in

  17. Gamma Knife Radiosurgery for Acromegaly

    Directory of Open Access Journals (Sweden)

    John D. Rolston

    2012-01-01

    Full Text Available Acromegaly is debilitating disease occasionally refractory to surgical and medical treatment. Stereotactic radiosurgery, and in particular Gamma Knife surgery (GKS, has proven to be an effective noninvasive adjunct to traditional treatments, leading to disease remission in a substantial proportion of patients. Such remission holds the promise of eliminating the need for expensive medications, along with side effects, as well as sparing patients the damaging sequelae of uncontrolled acromegaly. Numerous studies of radiosurgical treatments for acromegaly have been carried out. These illustrate an overall remission rate over 40%. Morbidity from radiosurgery is infrequent but can include cranial nerve palsies and hypopituitarism. Overall, stereotactic radiosurgery is a promising therapy for patients with acromegaly and deserves further study to refine its role in the treatment of affected patients.

  18. Development of a head phantom to be used for quality control in stereotactic radiosurgery; Desenvolvimento de um simulador de cabeca para a aplicacao no controle da qualidade de radiocirurgia estereotaxica

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Nilseia Aparecida

    2010-05-15

    It was designed and developed a geometric acrylic head phantom (GHP) for Quality Assurance (QA) in Stereotactic Radiosurgery (SRS). Inside the phantom there are inserts that are able to accommodate acrylic targets representing the tumor tissue and organ at risk in the region cranial brain, the brain stem. The tumor tissue is represented by two semi-spheres of acrylic with a diameter of 13.0 mm and cavities in the central region for accommodation of a TLD-100 detector and a small radiochromic EBT Gafchromic filmstrip. The brain stem is represented by the two parts of acrylic cylinder with a diameter 18.0 mm, 38.0 mm length and cavities along the central region to accommodate the 5 detectors TLD-100 and yet another of EBT film. The distance tumor - brain stem is 2.0 mm. The experimental setup was filled with water, attached to the stereotactic frame to determine the coordinates of the target and underwent computed tomography (CT). Cf images were transferred to the SRS planning system BrainLab (BrainScan). The contours of the lesion and organ at risk were delineated and, through the technique of multiple circular arcs, the planning was conduced with five arches, one isocenter and a collimator of 17.5 mm from the combination between the table and gantry . The dose delivered to the isocenter of the lesion was 3.0 Gy and the total coverage of tumor volume corresponds to the 75% isodose. This experimental arrangement is subjected to radiosurgery treatment, after which the dosimeters are evaluated and their responses compared with the values of planned doses. The linear accelerator used was a Varian CLlNAC 2300 CID, photon beam of 6 MV, installed at the National Cancer Institute (INCA). For verification of dose distributions in 3D, the films were irradiated in three planes: sagittal, caronal and axial. The .films were scanned and digitized on a scanner Microtek ScanMaker 9800XL model. The dose distributions in irradiated films were compared with the distributions of doses

  19. Study of the absorbed dose in small fields with absence of lateral electronic balance in stereotactic radiosurgery and radiotherapy with modulated intensity; Estudio de la dosis absorbida en campos pequenos con ausencia de equilibrio electronico lateral en radiocirugia estereotaxica y radioterapia con intensidad modulada

    Energy Technology Data Exchange (ETDEWEB)

    Vargas V, M. X.

    2013-07-01

    In this thesis we develop and experimental and theoretical study, using semi analytical techniques of the physical dosimetry for small and nonstandard fields for stereotactic radiosurgery (Srs) and intensity modulated radiation therapy (IMRT), with high energy photon beams from a BrainLAB system with cones at Instituto del Cancer SOLCA (Ecuador) and a Tomo Therapy Hi-Art system at Centro Oncologico de Chihuahua (Mexico). (Author)

  20. Long-Term Tumor Control despite Late Pseudoprogression on 18F-FDG-PET following Extremely Hypofractionated Stereotactic Radiotherapy for Retropharyngeal Lymph Node Metastasis from Esthesioneuroblastoma

    Directory of Open Access Journals (Sweden)

    Kazuhiro Ohtakara

    2014-08-01

    Full Text Available 18F-FDG-PET is a valuable adjunct to conventional imaging for evaluating treatment response following stereotactic body radiotherapy (SBRT for head and neck malignancies (HNM. The effect of treatment-related inflammation is generally deemed negligible after 12 weeks following conventionally fractionated radiotherapy. Herein, we describe an unusual case showing pseudoprogression on 18F-FDG-PET 2 years after SBRT for retropharyngeal lymph node metastasis (RPLNm from esthesioneuroblastoma. A 36-year-old man presented with right RPLNm 32 months after the diagnosis of esthesioneuroblastoma associated with ectopic adrenocorticotropic hormone production. The RPLNm was treated with SBRT in 2 fractions over 8 days using dynamic conformal arcs with concomitant chemotherapy with cisplatin and etoposide. Although follow-up MRI showed sustained lesion regression, the early/delayed maximum standardized uptake (SUVmax values on dual-time-point 18F-FDG-PET obtained 1 and 2 years after SBRT were 7.7/8.3 and 8.5/10.1, respectively, suggesting local progression. Despite no subsequent focal or systemic treatment, the SUVmax values gradually decreased thereafter over a period of 4 years (3.3/3.4 at 76 months. MRI obtained 7 years after SBRT revealed sustained tumor regression. No obvious relevant toxicities have occurred. Thus, caution should be exercised in the interpretation of the SUVmax change following ablative irradiation for HNM.

  1. Long-term local control achieved after hypofractionated stereotactic body radiotherapy for adrenal gland metastases: A retrospective analysis of 34 patients

    Energy Technology Data Exchange (ETDEWEB)

    Scorsetti, Marta; Alongi, Filippo [Radiotherapy and Radiosurgery Dept., IRCCS Istituto Clinico Humanitas, Humanitas Cancer Center, Rozzano, Milano (Italy)], Email: filippo.alongi@humanitas.it; Filippi, Andrea Riccardo [Radiation Oncology Unit, Dept. of Medical and Surgical Sciences, Univ. of Turin, Turin (Italy)] [and others

    2012-05-15

    Aims and background. To describe feasibility, tolerability and clinical outcomes of stereotactic body radiation therapy (SBRT) in the treatment of adrenal metastases in 34 consecutive cancer patients. Material and methods. Between March 2004 and July 2010, a total of 34 consecutive patients, accounting for 36 adrenal metastatic lesions, were treated with SBRT. SBRT treatments were delivered by a Linac Varian 600 with microMLC (3DLine, Elekta, Stockholm, Sweden) and a Linac ELEKTA Precise (Elekta). All 34 patients were clinically and radiologically evaluated during and after completion of SBRT. Following outcomes were taken into account: best clinical response at any time, local control, time to systemic progression, time to local progression, overall survival and toxicity. Survival was estimated by the Kaplan-Meier method and factor potentially affecting outcomes were analyzed with Cox regression analysis. Results. Total RT doses ranged from 20 Gy in 4 fractions to 45 Gy in 18 fractions (median dose: 32 Gy; median number of fractions: 4). All doses were prescribed to the 95% isodose line. No cases of Grade {>=} 3 toxicity were recorded. At a median follow-up time of 41 months (range, 12-75) 22 patients were alive. Three of 28 lesions (11%) showed complete response, 13/28 (46%) partial response, 10/28 (36%) stable disease and 2/28 (7%) progressed in the treated area. Local failure was observed in 13 cases. Actuarial local control rates at one and two years were 66% and 32%, respectively. Median time to local progression was 19 months. Median survival was 22 months. Conclusion. SBRT in adrenal gland metastasis is feasible without significant acute and late toxicities, with a good rate of local control. New SBRT fractionation schemes and the possibility to combine new systemic approaches should be investigated in order to further increase local control and reduce systemic disease progression.

  2. Feasibility report of image guided stereotactic body radiotherapy (IG-SBRT) with tomotherapy for early stage medically inoperable lung cancer using extreme hypofractionation

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Wes; Tome, Wolfgang A.; Jaradat, Hazim A.; Orton, Nigel P.; Khuntia, Deepak; Mehta, Minesh P. [Univ. of Wisconsin School of Medicine and Public Health, Madison, WI (United States). Dept. of Human Oncology; Traynor, Anne [Univ. of Wisconsin School of Medicine and Public Health, Madison, WI (United States). Dept. of Medicine; Weigel, Tracey [Univ. of Wisconsin School of Medicine and Public Health, Madison, WI (United States). Dept. of Surgery

    2006-09-15

    We report on the technical feasibility, dosimetric aspects, and daily image-guidance capability with megavoltage CT (MVCT) of stereotactic body radiotherapy (SBRT) using helical tomotherapy for medically inoperable T1/2 N0 M0 non-small cell lung cancer. Nine patients underwent treatment planning with 4D-CT in a double vacuum based immobilization system to minimize tumor motion and to define a lesion-specific 4D-motion envelope. Patients received 60 Gy in 5 fractions within 10 days to a PTV defined by a motion envelope plus a 6 mm expansion for microscopic extension and setup error using tomotherapy, with daily pretreatment MVCT image guidance. The primary endpoint was technical feasibility. Secondary endpoints were defining the acute and sub-acute toxicities and tumor response. Forty three of 45 fractions were successfully delivered, with an average delivery time of 22 minutes. MVCT provided excellent tumor visualization for daily image guidance. No significant tumor regression was observed on MVCT in any patient during therapy. Median mean normalized total doses were: tumor 117 Gy{sub 10}; residual lung 9 Gy{sub 3}. Maximum fraction-size equivalent dose values were: esophagus 5 Gy{sub 3}{sup 9}; cord 7 Gy{sub 3}{sup 6}. No patient experienced = grade 2 pulmonary toxicity. 3 complete, 4 partial and 2 stable responses were observed, with <3 months median follow-up. The mean tumor regression is 72%. SBRT using tomotherapy proved to be feasible, safe and free of major technical limitations or acute toxicities. Daily pretreatment MVCT imaging allows for precise daily tumor targeting with the patient in the actual treatment position, and therefore provides for precise image guidance.

  3. Long-term outcome and toxicity of hypofractionated stereotactic body radiotherapy as a boost treatment for head and neck cancer: the importance of boost volume assessment

    Directory of Open Access Journals (Sweden)

    Lee Dong

    2012-06-01

    Full Text Available Abstract Background The aim of this study was to report the long-term clinical outcomes of patients who received stereotactic body radiotherapy (SBRT as a boost treatment for head and neck cancer. Materials and methods Between March 2004 and July 2007, 26 patients with locally advanced, medically inoperable head and neck cancer or gross residual tumors in close proximity to critical structures following head and neck surgery were treated with SBRT as a boost treatment. All patients were initially treated with standard external beam radiotherapy (EBRT. SBRT boost was prescribed to the median 80% isodose line with a median dose of 21 (range 10–25 Gy in 2–5 (median, 5 fractions. Results The median follow-up after SBRT was 56 (range 27.6 − 80.2 months. The distribution of treatment sites in 26 patients was as follows: the nasopharynx, including the base of the skull in 10 (38.5%; nasal cavity or paranasal sinus in 8 (30.8%; periorbit in 4 (15.4%; tongue in 3 (11.5%; and oropharyngeal wall in 1 (3.8%. The median EBRT dose before SBRT was 50.4 Gy (range 39.6 − 70.2. The major response rate was 100% with 21 (80.8% complete responses (CR. Severe (grade ≥ 3 late toxicities developed in 9 (34.6% patients, and SBRT boost volume was a significant parameter predicting severe late complication. Conclusions The present study demonstrates that a modern SBRT boost is a highly efficient tool for local tumor control. However, we observed a high frequency of serious late complications. More optimized dose fractionation schedule and patient selection are required to achieve excellent local control without significant late morbidities in head and neck boost treatment.

  4. Hypofractionated stereotactic body radiotherapy for primary and metastatic liver tumors using the novalis image-guided system: preliminary results regarding efficacy and toxicity.

    Science.gov (United States)

    Iwata, Hiromitsu; Shibamoto, Yuta; Hashizume, Chisa; Mori, Yoshimasa; Kobayashi, Tatsuya; Hayashi, Naoki; Kosaki, Katsura; Ishikawa, Tetsuya; Kuzuya, Teiji; Utsunomiya, Setsuo

    2010-12-01

    www.tcrt.org The purpose of this study was to evaluate the efficacy and toxicity of stereotactic body radiotherapy (SBRT) for primary and metastatic liver tumors using the Novalis image-guided radiotherapy system. After preliminarily treating liver tumors using the Novalis system from July 2006, we started a protocol-based study in February 2008. Eighteen patients (6 with primary hepatocellular carcinoma and 12 with metastatic liver tumor) were treated with 55 or 50 Gy, depending upon their planned dose distribution and liver function, delivered in 10 fractions over 2 weeks. Four non-coplanar and three coplanar static beams were used. Patient age ranged from 54 to 84 years (median: 72 years). The Child-Pugh classification was Grade A in 17 patients and Grade B in 1. Tumor diameter ranged from 12 to 35 mm (median: 23 mm). Toxicities were evaluated according to the Common Terminology Criteria of Adverse Events version 4.0, and radiation-induced liver disease (RILD) was defined by Lawrence's criterion. The median follow-up period was 14.5 months. For all patients, the 1-year overall survival and local control rates were 94% and 86%, respectively. A Grade 1 liver enzyme change was observed in 5 patients, but no RILD or chronic liver dysfunction was observed. SBRT using the Novalis image-guided system is safe and effective for treating primary and metastatic liver tumors. Further investigation of SBRT for liver tumors is warranted. In view of the acceptable toxicity observed with this protocol, we have moved to a new protocol to shorten the overall treatment time and escalate the dose.

  5. Factors determining field of tapered beams in a unit stereotactic radiosurgery; Determinacion de factores campo de haces conicos en una unidad de radiocirugia estereotaxica

    Energy Technology Data Exchange (ETDEWEB)

    Brosed Aguillon, M. L.; Casal Mesa, M. D.; Forastero, C.; Sanchez Reyes, A.

    2013-07-01

    The difficulty of measuring small fields in radiosurgery, obliges the use of different detectors for measuring these beams tapered. Measures with two different detectors, should be coupled, through a middle ground, in which both detectors have a similar response. The objective will be to determine the factors of field of all the cones and the comparison with the results of other authors. (Author)

  6. [Stereotactic radiation therapy].

    Science.gov (United States)

    Aristu, J J; Ciérvide, R; Guridi, J; Moreno, M; Arbea, L; Azcona, J D; Ramos, L I; Zubieta, J L

    2009-01-01

    Stereotactic radiotherapy is a form of external radiotherapy that employs a system of three dimensional coordinates independent of the patient for the precise localisation of the lesion. It also has the characteristic that the radiation beams are conformed and precise, and converge on the lesion, making it possible to administer very high doses of radiotherapy without increasing the radiation to healthy adjacent organs or structures. When the procedure is carried out in one treatment session it is termed radiosurgery, and when administered over several sessions it is termed stereotactic radiotherapy. Special systems of fixing or immobilising the patient (guides or stereotactic frames) are required together with radiotherapy devices capable of generating conformed beams (lineal accelerator, gammaknife, cyberknife, tomotherapy, cyclotrons). Modern stereotactic radiotherapy employs intra-tumoural radio-opaque frames or CAT image systems included in the irradiation device, which make possible a precise localisation of mobile lesions in each treatment session. Besides, technological advances make it possible to coordinate the lesion's movements in breathing with the radiotherapy unit (gating and tracking) for maximum tightening of margins and excluding a greater volume of healthy tissue. Radiosurgery is mainly indicated in benign or malign cerebral lesions less than 3-4 centimetres (arteriovenous malformations, neurinomas, meningiomas, cerebral metastases) and stereotactic radiotherapy is basically administered in tumours of extracraneal localisation that require high conforming and precision, such as inoperable early lung cancer and hepatic metastasis.

  7. An Overview of CyberKnife Radiosurgery

    Institute of Scientific and Technical Information of China (English)

    Wenyu Cheng; John R. Adler Jr.

    2006-01-01

    Stereotactic radiosurgery is a non-invasive procedure that utilizes precisely targeted radiation as an ablative surgical tool. Conventional radiosurgery devices, such as the Gamma Knife, rely upon skeletally attached stereotactic frames to immobilize the patient and precisely determine the 3D spatial position of a tumor. A relatively new instrument, the CyberKnife (Accuray, Inc., Sunnyvale, CA), makes it possible to administer radiosurgery without a frame. The CyberKnife localizes clinical targets using a very accurate image-to-image correlation algorithm, and precisely cross-fires high-energy radiation from a lightweight linear accelerator by means of a highly manipulable robotic arm. CyberKnife radiosurgery is an effective alternative to conventional surgery or radiation therapy for a range of tumors and some non-neoplastic disorders. This report will describe CyberKnife technology and oncologic applications in neurosurgery and throughout the body.

  8. SU-E-J-13: Six Degree of Freedom Image Fusion Accuracy for Cranial Target Localization On the Varian Edge Stereotactic Radiosurgery System: Comparison Between 2D/3D and KV CBCT Image Registration

    Energy Technology Data Exchange (ETDEWEB)

    Xu, H [Wayne State University, Detroit, MI (United States); Song, K; Chetty, I; Kim, J [Henry Ford Health System, Detroit, MI (United States); Wen, N [Henry Ford Health System, West Bloomfield, MI (United States)

    2015-06-15

    -based system provides accurate target positioning for frameless image-guided cranial stereotactic radiosurgery.

  9. A Phase 3 Trial of Whole Brain Radiation Therapy and Stereotactic Radiosurgery Alone Versus WBRT and SRS With Temozolomide or Erlotinib for Non-Small Cell Lung Cancer and 1 to 3 Brain Metastases: Radiation Therapy Oncology Group 0320

    Energy Technology Data Exchange (ETDEWEB)

    Sperduto, Paul W., E-mail: psperduto@mropa.com [Metro MN CCOP, Minneapolis, Minnesota (United States); Wang, Meihua [RTOG Statistical Center, Philadelphia, Pennsylvania (United States); Robins, H. Ian [University of Wisconsin Medical School Cancer Center, Madison, Wisconsin (United States); Schell, Michael C. [Wilmot Cancer Center, University of Rochester, Rochester, New York (United States); Werner-Wasik, Maria [Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Komaki, Ritsuko [University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Souhami, Luis [McGill University, Montreal, Quebec (Canada); Buyyounouski, Mark K. [Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Khuntia, Deepak [University of Wisconsin Hospital, Madison, Wisconsin (United States); Demas, William [Akron City Hospital, Akron, Ohio (United States); Shah, Sunjay A. [Christiana Care Health Services, Inc, CCOP, Newark, Delaware (United States); Nedzi, Lucien A. [University of Texas Southwestern Medical School, Dallas, Texas (United States); Perry, Gad [The Ottawa Hospital Cancer Centre, Ottawa, Ontario (Canada); Suh, John H. [Cleveland Clinic Foundation, Cleveland, Ohio (United States); Mehta, Minesh P. [Northwestern Memorial Hospital, Chicago, Illinois (United States)

    2013-04-01

    Background: A phase 3 Radiation Therapy Oncology Group (RTOG) study subset analysis demonstrated improved overall survival (OS) with the addition of stereotactic radiosurgery (SRS) to whole brain radiation therapy (WBRT) in non-small cell lung cancer (NSCLC) patients with 1 to 3 brain metastases. Because temozolomide (TMZ) and erlotinib (ETN) cross the blood-brain barrier and have documented activity in NSCLC, a phase 3 study was designed to test whether these drugs would improve the OS associated with WBRT + SRS. Methods and Materials: NSCLC patients with 1 to 3 brain metastases were randomized to receive WBRT (2.5 Gy × 15 to 37.5 Gy) and SRS alone, versus WBRT + SRS + TMZ (75 mg/m{sup 2}/day × 21 days) or ETN (150 mg/day). ETN (150 mg/day) or TMZ (150-200 mg/m{sup 2}/day × 5 days/month) could be continued for as long as 6 months after WBRT + SRS. The primary endpoint was OS. Results: After 126 patients were enrolled, the study closed because of accrual limitations. The median survival times (MST) for WBRT + SRS, WBRT + SRS + TMZ, and WBRT + SRS + ETN were qualitatively different (13.4, 6.3, and 6.1 months, respectively), although the differences were not statistically significant. Time to central nervous system progression and performance status at 6 months were better in the WBRT + SRS arm. Grade 3 to 5 toxicity was 11%, 41%, and 49% in arms 1, 2, and 3, respectively (P<.001). Conclusion: The addition of TMZ or ETN to WBRT + SRS in NSCLC patients with 1 to 3 brain metastases did not improve survival and possibly had a deleterious effect. Because the analysis is underpowered, these data suggest but do not prove that increased toxicity was the cause of inferior survival in the drug arms.

  10. Effects and prognostic factors of hypofractionated stereotactic radiotherapy for brain metastasis in non-small cell lung cancer%大分割立体定向放射治疗NSCLC脑转移的临床观察

    Institute of Scientific and Technical Information of China (English)

    斯琴高娃; 李墨

    2012-01-01

    OBJECTIVE: To study the effects and prognostic factors for patients with brain metastases in non-small cell lung cancer (NSCLC) treated by hypofractionated stereotactic radiotherapy (HSRT). METHODS: A total of 60 patients with brain metastasis were recruited, which included 124 metastatic lesions. All patients received the treatment of HSRT. Ninety metastasis lesions received the HSRT plus whole brain radiotherapy, and thirty-four lesions received the HSRT alone. Median follow up time was 12 months. The effective rate and prognostic factors were observed and analyzed accordingly. RESULTS: In group of receiving HSRT with whole brain radiotherapy, forty-six of metastasis lesions were reached to complete remission (CR) , 28 to partial remision (PR), 9 to stable disease(SD), and 7 to progressive disease(PD). Local-control (LC) rate at 6- and 12-month was 92. 3% and 66. 9%, and the overall survival (OS) rate was 73. 2% and 47.6%, respectively. In group of receiving HSRT alone, twenty of metastasis lesions were reached for CR, 7 for PR, 4 for SD, and 3 for PD. LC rate at 6- and 12- month was 92. 7% and 65. 9% and the OS rate was 70. 2% and 45. 8% , respectively. Multivariate analysis showed that the amount of the metastasis lesions (OR= 1. 675, P=0. 001), extracranial metastasis (OR=1. 934, P. 036) and the control of the primary tumor (OR=7. 936, P=0. 033) were the independent factors for the OS. CONCLUSIONS; HSRT is one of the efficacious methods for the treatment in NSCLC patients with brain metastases. Numbers of brain metastasis lesions, extracranial metastasis and controlled primary lesion are independent prognostic factors.%目的:分析大分割立体定向放射治疗(HSRT)非小细胞肺癌(NSCLC)脑转移的有效性及预后因素.方法:选取60例有1 24个脑转移病灶的NSCLC患者进行HSRT,其中90个病变进行全脑放射治疗加HSRT,34个病变初始进行HSRT,中位随访12个月.观察近期疗效及预后因素.结果:全脑放疗加HSRT组46

  11. 大剂量多次分割立体定向放疗对听神经瘤的疗效分析%Clinical Efficacy of Hypofractionated Stereotactic Radiotherapy in Five Fractions for Acoustic Neuromas

    Institute of Scientific and Technical Information of China (English)

    陈志萍; 溝脇尚志; 小倉健; 宇藤惠; 平岡眞寛

    2015-01-01

    目的:评价大剂量分割立体定向放疗(hypo-FSRT)治疗听神经瘤患者在肿瘤局部控制及有效听力保存等方面的临床价值。方法回顾性分析47例单侧听神经瘤患者,中位年龄61岁,放疗前19例患者持有有效听力,肿瘤最大径中位值20 mm,处方剂量:等中心总剂量25 Gy,5次分割,每日1次,80%剂量曲线包绕计划靶区( PTV)边缘。采用实体瘤消退评价标准( RECIST)改良版1.1评估肿瘤消退情况。采用Gardner-Robertson Class 评估听力保存情况。 SPSS 18.0软件进行统计分析。结果中位随访及听力随访时间分别为61及52个月,30例(63.8%)、13例(27.67%)及4例(8.5%)患者分别出现肿瘤部分缩退(PR)、稳定(SD)、进展(PD),根据Kaplan-Meier生存分析,5年肿瘤局部控制率为90.4%,放疗前肿瘤是否合并囊变成分在肿瘤控制方面存在显著性差异(P=0.015),合并囊变的肿瘤预示放疗后出现肿瘤进展的可能性大。放疗后14例(29.8%)患者出现肿瘤暂时性增大。1、3、5年患者有效听力保存率分别为68.4%,62.1%及35.5%。有效听力保存与未保存患者在肿瘤消退情况方面存在明显差异(P=0.017)。1例(2.1%)患者行挽救性手术,2例(4.3%)患者行VP-脑室分流术,2例(4.3%)患者新出现三叉神经轻度麻痹。结论 Hypo-FSRT (25 Gy/5次)治疗单侧听神经瘤可有效控制肿瘤,放疗后并发症发生率低。影像定期随访中观察到肿瘤暂时性增大及逐渐缩退过程。放疗前肿瘤合并囊变预示患者放疗后出现肿瘤进展的机率更高。%Objective To study the clinical outcomes of hypofractionated stereotactic radiotherapy ( hypo-FSRT) for a-coustic neuromas (ANs).Methods 47 patients with unilateral acoustic neuroma were treated consecutively with hypo -FSRT. The median age was 61 years old

  12. Dosimetric characterization of a set of circular collimators taper functional radiosurgery; Caracterizacion dosimetrica de un conjunto de colimadores circulares conicos para radiocirugia funcional

    Energy Technology Data Exchange (ETDEWEB)

    Zucca Aparicio, D.; Perez Moreno, J. M.; Fernandez Leton, P.; Garcia Ruiz-Zorrila, J.; Minambres Moro, A.

    2011-07-01

    Functional radiosurgery is a treatment modality for stereotactic radiosurgery (SRS) based on tapered circular collimators which usually require cones small (up to 4.0 mm in diameter). This paper summarizes the results for the dosimetric characterization of a set of circular collimators for radiosurgery planning system prior to clinical implementation of such treatments for patients treated with SRS. (Author)

  13. Phase I trial of carboplatin and gemcitabine chemotherapy and stereotactic ablative radiosurgery for the palliative treatment of persistent or recurrent gynecologic cancer

    Directory of Open Access Journals (Sweden)

    Charles A Kunos

    2015-06-01

    Full Text Available Background: We conducted a phase I trial to determine the safety of systemic chemotherapy prior to abdominopelvic robotic stereotactic ablative radiotherapy (SABR in women with persistent or recurrent gynecologic cancers. Methods: Patients were assigned to dose-finding cohorts of day-1 carboplatin (AUC 2 or 4 and gemcitabine (600 or 800 mg/m2 followed by day-2 to day-4 Cyberknife SABR (8Gy X 3 consecutive daily doses. Toxicities were graded prospectively by common terminology criteria for adverse events, version 4.0. SABR target and best overall treatment responses were recorded according to response evaluation criteria in solid tumors, version 1.1. Findings: The maximum tolerated dose of chemotherapy preceding SABR was carboplatin AUC 4 and gemcitabine 600 mg/m2. One patient experienced manageable, dose-limiting grade 4 neutropenia, grade 4 hypokalemia, and grade 3 nausea attributed to study treatment. One patient had a late grade 3 rectovaginal fistula 16 months after trial therapy. Among 28 SABR targets, 22 (79% showed a partial response and six (21% remained stable. Interpretation: Systemic chemotherapy may be given safely prior to abdominopelvic robotic SABR with further investigation warranted.Funding: National Institutes of Health grant P30 CA43703

  14. Influence of eye size and beam entry angle on dose to non-targeted tissues of the eye during stereotactic x-ray radiosurgery of AMD

    Science.gov (United States)

    Cantley, Justin L.; Hanlon, Justin; Chell, Erik; Lee, Choonsik; Smith, W. Clay; Bolch, Wesley E.

    2013-10-01

    Age-related macular degeneration is a leading cause of vision loss for the elderly population of industrialized nations. The IRay® Radiotherapy System, developed by Oraya® Therapeutics, Inc., is a stereotactic low-voltage irradiation system designed to treat the wet form of the disease. The IRay System uses three robotically positioned 100 kVp collimated photon beams to deliver an absorbed dose of up to 24 Gy to the macula. The present study uses the Monte Carlo radiation transport code MCNPX to assess absorbed dose to six non-targeted tissues within the eye—total lens, radiosensitive tissues of the lens, optic nerve, distal tip of the central retinal artery, non-targeted portion of the retina, and the ciliary body--all as a function of eye size and beam entry angle. The ocular axial length was ranged from 20 to 28 mm in 2 mm increments, with the polar entry angle of the delivery system varied from 18° to 34° in 2° increments. The resulting data showed insignificant variations in dose for all eye sizes. Slight variations in the dose to the optic nerve and the distal tip of the central retinal artery were noted as the polar beam angle changed. An increase in non-targeted retinal dose was noted as the entry angle increased, while the dose to the lens, sensitive volume of the lens, and ciliary body decreased as the treatment polar angle increased. Polar angles of 26° or greater resulted in no portion of the sensitive volume of the lens receiving an absorbed dose of 0.5 Gy or greater. All doses to non-targeted structures reported in this study were less than accepted thresholds for post-procedure complications.

  15. Contribution to the planning and dosimetry of photon beams applied to radiosurgery and stereotactic radiotherapy; Contribuicao ao planejamento e a dosimetria de feixes de fotons aplicados a radiocirurgia e a radioterapia estereotaxica

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Walter Menezes

    2003-08-15

    Radiosurgery and stereotactic radiotherapy are irradiation techniques that use small diameter photon beams for treating intracranial lesions such as pituitary adenomas, acoustic tumors and arterio-venous malformations which are inaccessible for surgery. These treatment techniques are characterized by the use of very small radiation beams which deliver a precisely measured dose to the target volume, while sparing the surrounding healthy tissue. Treatment can be performed by using multiple {sup 60}Co gamma-ray sources (in the so-called 'Gamma Knife'), charged particles or X-ray beams produced by linear accelerators. The prescribed dose can be given in a single session or in multiple fractions, as in conventional radiotherapy. The success of the treatment depends, among other factors, of the accurate determination of the parameters that characterize the radiation beam produced by the equipment, as well as, of a well designed quality assurance program. In this study, the dosimetric parameters of a set of collimating cones of a Radionics{sup TM} treatment system applied to two 6 MV- photon beams (Clinac 600C - Varian{sup TM}, and Mevatron MD2 - Siemens{sup TM}) were evaluated by using a water filled PMMA simulator. Measurements were carried out for photon beam diameters ranging from 12.5 to 40.0 mm for the Clinac-600C and from 5.0 to 50.0 mm for the Mevatron MD2. The parameters were evaluated by using a parallel plate ionization chamber (Markus), Kodak X-Omat V dosimetric films, thermoluminescent dosemeters (Harschaw, TLD-100) and photodiodes. The maximum tissue-ratio, the off-axis profile and the output factors were determined and the results were compared to those reported elsewhere. A study of the dosimetric characteristics of some commercially available phototransistors was also carried out. The results showed that these electronic components can be successfully used for measuring the dosimetric parameters of small diameter photon beans used in

  16. Secondary analysis of RTOG 9508, a phase 3 randomized trial of whole-brain radiation therapy versus WBRT plus stereotactic radiosurgery in patients with 1-3 brain metastases; poststratified by the graded prognostic assessment (GPA).

    Science.gov (United States)

    Sperduto, Paul W; Shanley, Ryan; Luo, Xianghua; Andrews, David; Werner-Wasik, Maria; Valicenti, Richard; Bahary, Jean-Paul; Souhami, Luis; Won, Minhee; Mehta, Minesh

    2014-11-01

    Radiation Therapy Oncology Group (RTOG) 9508 showed a survival advantage for patients with 1 but not 2 or 3 brain metastasis (BM) treated with whole-brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) versus WBRT alone. An improved prognostic index, the graded prognostic assessment (GPA) has been developed. Our hypothesis was that if the data from RTOG 9508 were poststratified by the GPA, the conclusions may vary. In this analysis, 252 of the 331 patients were evaluable by GPA. Of those, 211 had lung cancer. Breast cancer patients were excluded because the components of the breast GPA are not in the RTOG database. Multiple Cox regression was used to compare survival between treatment groups, adjusting for GPA. Treatment comparisons within subgroups were performed with the log-rank test. A free online tool (brainmetgpa.com) simplified GPA use. The fundamental conclusions of the primary analysis were confirmed in that there was no survival benefit overall for patients with 1 to 3 metastases; however, there was a benefit for the subset of patients with GPA 3.5 to 4.0 (median survival time [MST] for WBRT + SRS vs WBRT alone was 21.0 versus 10.3 months, P=.05) regardless of the number of metastases. Among patients with GPA 3.5 to 4.0 treated with WBRT and SRS, the MST for patients with 1 versus 2 to 3 metastases was 21 and 14.1 months, respectively. This secondary analysis of predominantly lung cancer patients, consistent with the original analysis, shows no survival advantage for the group overall when treated with WBRT and SRS; however, in patients with high GPA (3.5-4), there is a survival advantage regardless of whether they have 1, 2, or 3 BM. This benefit did not extend to patients with lower GPA. Prospective validation of this survival benefit for patients with multiple BM and high GPA when treated with WBRT and SRS is warranted. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Secondary Analysis of RTOG 9508, a Phase 3 Randomized Trial of Whole-Brain Radiation Therapy Versus WBRT Plus Stereotactic Radiosurgery in Patients With 1-3 Brain Metastases; Poststratified by the Graded Prognostic Assessment (GPA)

    Energy Technology Data Exchange (ETDEWEB)

    Sperduto, Paul W., E-mail: psperduto@mropa.com [Metro-Minnesota CCOP and Minneapolis Radiation Oncology, Minneapolis, Minnesota (United States); Shanley, Ryan [Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota (United States); Luo, Xianghua [Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota (United States); Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota (United States); Andrews, David [Thomas Jefferson University, Department of NeuroOncology, Philadelphia, Pennsylvania (United States); Werner-Wasik, Maria [Thomas Jefferson University, Department of Radiation Oncology, Philadelphia, Pennsylvania (United States); Valicenti, Richard [UC Davis Medical Center, Department of Radiation Oncology, Sacramento, California (United States); Bahary, Jean-Paul [CHUM Hospital Notre Dame, Quebec (Canada); Souhami, Luis [McGill University, Montreal, Quebec (Canada); Won, Minhee [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Mehta, Minesh [University of Maryland Medical System, Baltimore, Maryland (United States)

    2014-11-01

    Purpose: Radiation Therapy Oncology Group (RTOG) 9508 showed a survival advantage for patients with 1 but not 2 or 3 brain metastasis (BM) treated with whole-brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) versus WBRT alone. An improved prognostic index, the graded prognostic assessment (GPA) has been developed. Our hypothesis was that if the data from RTOG 9508 were poststratified by the GPA, the conclusions may vary. Methods and Materials: In this analysis, 252 of the 331 patients were evaluable by GPA. Of those, 211 had lung cancer. Breast cancer patients were excluded because the components of the breast GPA are not in the RTOG database. Multiple Cox regression was used to compare survival between treatment groups, adjusting for GPA. Treatment comparisons within subgroups were performed with the log-rank test. A free online tool ( (brainmetgpa.com)) simplified GPA use. Results: The fundamental conclusions of the primary analysis were confirmed in that there was no survival benefit overall for patients with 1 to 3 metastases; however, there was a benefit for the subset of patients with GPA 3.5 to 4.0 (median survival time [MST] for WBRT + SRS vs WBRT alone was 21.0 versus 10.3 months, P=.05) regardless of the number of metastases. Among patients with GPA 3.5 to 4.0 treated with WBRT and SRS, the MST for patients with 1 versus 2 to 3 metastases was 21 and 14.1 months, respectively. Conclusions: This secondary analysis of predominantly lung cancer patients, consistent with the original analysis, shows no survival advantage for the group overall when treated with WBRT and SRS; however, in patients with high GPA (3.5-4), there is a survival advantage regardless of whether they have 1, 2, or 3 BM. This benefit did not extend to patients with lower GPA. Prospective validation of this survival benefit for patients with multiple BM and high GPA when treated with WBRT and SRS is warranted.

  18. Stereotactic Radiosurgery With or Without Whole-Brain Radiation Therapy for Limited Brain Metastases: A Secondary Analysis of the North Central Cancer Treatment Group N0574 (Alliance) Randomized Controlled Trial.

    Science.gov (United States)

    Churilla, Thomas M; Ballman, Karla V; Brown, Paul D; Twohy, Erin L; Jaeckle, Kurt; Farace, Elana; Cerhan, Jane H; Anderson, S Keith; Carrero, Xiomara W; Garces, Yolanda I; Barker, Fred G; Deming, Richard; Dixon, Jesse G; Burri, Stuart H; Chung, Caroline; Ménard, Cynthia; Stieber, Volker W; Pollock, Bruce E; Galanis, Evanthia; Buckner, Jan C; Asher, Anthony L

    2017-08-05

    To determine whether whole-brain radiation therapy (WBRT) is associated with improved overall survival among non-small cell lung cancer (NSCLC) patients with favorable prognoses at diagnosis. In the N0574 trial, patients with 1 to 3 brain metastases were randomized to receive stereotactic radiosurgery (SRS) or SRS plus WBRT (SRS + WBRT), with a primary endpoint of cognitive deterioration. We calculated diagnosis-specific graded prognostic assessment (DS-GPA) scores for NSCLC patients and evaluated overall survival according to receipt of WBRT and DS-GPA score using 2 separate cut-points (≥2.0 vs <2.0 and ≥2.5 vs <2.5). A total of 126 NSCLC patients were included for analysis, with median follow-up of 14.2 months. Data for DS-GPA calculation were available for 86.3% of all enrolled NSCLC patients. Overall, 50.0% of patients had DS-GPA score ≥2.0, and 23.0% of patients had DS-GPA scores ≥2.5. The SRS and SRS + WBRT groups were well balanced with regard to prognostic factors. The median survival according to receipt of WBRT was 11.3 months (+WBRT) and 17.9 months (-WBRT) for patients with DS-GPA ≥2.0 (favorable prognoses, P=.63; hazard ratio 0.86; 95% confidence interval 0.47-1.59). Median survival was 3.7 months (+WBRT) and 6.6 months (-WBRT) for patients with DS-GPA <2.0 patients (unfavorable prognoses, P=.85; hazard ratio 0.95; 95% confidence interval 0.56-1.62). Outcomes according to the receipt of WBRT and DS-GPA remained similar utilizing DS-GPA ≥2.5 as a cutoff for favorable prognoses. There was no interaction between the continuum of the DS-GPA groups and WBRT on overall survival (P=.53). We observed no significant differences in survival according to receipt of WBRT in favorable-prognosis NSCLC patients. This study further supports the approach of SRS alone in the majority of patients with limited brain metastases. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Creation of a Prognostic Index for Spine Metastasis to Stratify Survival in Patients Treated With Spinal Stereotactic Radiosurgery: Secondary Analysis of Mature Prospective Trials

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chad [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hess, Kenneth [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Bishop, Andrew J.; Pan, Hubert Y.; Christensen, Eva N. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Yang, James N. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tannir, Nizar [Department of Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Amini, Behrang [Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tatsui, Claudio; Rhines, Laurence [Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Brown, Paul [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Ghia, Amol, E-mail: ajghia@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2015-09-01

    Purpose: There exists uncertainty in the prognosis of patients following spinal metastasis treatment. We sought to create a scoring system that stratifies patients based on overall survival. Methods and Materials: Patients enrolled in 2 prospective trials investigating stereotactic spine radiation surgery (SSRS) for spinal metastasis with ≥3-year follow-up were analyzed. A multivariate Cox regression model was used to create a survival model. Pretreatment variables included were race, sex, age, performance status, tumor histology, extent of vertebrae involvement, previous therapy at the SSRS site, disease burden, and timing of diagnosis and metastasis. Four survival groups were generated based on the model-derived survival score. Results: Median follow-up in the 206 patients included in this analysis was 70 months (range: 37-133 months). Seven variables were selected: female sex (hazard ratio [HR] = 0.7, P=.02), Karnofsky performance score (HR = 0.8 per 10-point increase above 60, P=.007), previous surgery at the SSRS site (HR = 0.7, P=.02), previous radiation at the SSRS site (HR = 1.8, P=.001), the SSRS site as the only site of metastatic disease (HR = 0.5, P=.01), number of organ systems involved outside of bone (HR = 1.4 per involved system, P<.001), and >5 year interval from initial diagnosis to detection of spine metastasis (HR = 0.5, P<.001). The median survival among all patients was 25.5 months and was significantly different among survival groups (in group 1 [excellent prognosis], median survival was not reached; group 2 reached 32.4 months; group 3 reached 22.2 months; and group 4 [poor prognosis] reached 9.1 months; P<.001). Pretreatment symptom burden was significantly higher in the patient group with poor survival than in the group with excellent survival (all metrics, P<.05). Conclusions: We developed the prognostic index for spinal metastases (PRISM) model, a new model that identified patient subgroups with poor and excellent prognoses.

  20. Particle radiosurgery: a new frontier of physics in medicine.

    Science.gov (United States)

    Bert, Christoph; Durante, Marco

    2014-07-01

    Radiosurgery was introduced over half a century ago for treatment of intracranial lesions. In more recent years, stereotactic radiotherapy has rapidly advanced and is now commonly used for treatments of both cranial and extracranial lesions with high doses delivered in a few, down to a single fraction. The results of a workshop on Particle radiosurgery: A new frontier of physics in medicine held at Obergurgl, Austria during August 25-29 2013 are summarized in this issue with an overview presented in this paper. The focus was laid on particle radiosurgery but the content also includes current practice in x-ray radiosurgery and the overarching research in radiobiology and motion management for extracranial lesions. The results and discussions showed that especially research in radiobiology of high-dose charged-particles and motion management are necessary for the success of particle radiosurgery.

  1. Hypofractionation in Prostate Cancer: Radiobiological Basis and Clinical Appliance

    Directory of Open Access Journals (Sweden)

    M. Mangoni

    2014-01-01

    Full Text Available External beam radiation therapy with conventional fractionation to a total dose of 76–80 Gy represents the most adopted treatment modality for prostate cancer. Dose escalation in this setting has been demonstrated to improve biochemical control with acceptable toxicity using contemporary radiotherapy techniques. Hypofractionated radiotherapy and stereotactic body radiation therapy have gained an increasing interest in recent years and they have the potential to become the standard of care even if long-term data about their efficacy and safety are not well established. Strong radiobiological basis supports the use of high dose for fraction in prostate cancer, due to the demonstrated exceptionally low values of α/β. Clinical experiences with hypofractionated and stereotactic radiotherapy (with an adequate biologically equivalent dose demonstrated good tolerance, a PSA control comparable to conventional fractionation, and the advantage of shorter time period of treatment. This paper reviews the radiobiological findings that have led to the increasing use of hypofractionation in the management of prostate cancer and briefly analyzes the clinical experience in this setting.

  2. Hypofractionation in prostate cancer: radiobiological basis and clinical appliance.

    Science.gov (United States)

    Mangoni, M; Desideri, I; Detti, B; Bonomo, P; Greto, D; Paiar, F; Simontacchi, G; Meattini, I; Scoccianti, S; Masoni, T; Ciabatti, C; Turkaj, A; Serni, S; Minervini, A; Gacci, M; Carini, M; Livi, L

    2014-01-01

    External beam radiation therapy with conventional fractionation to a total dose of 76-80 Gy represents the most adopted treatment modality for prostate cancer. Dose escalation in this setting has been demonstrated to improve biochemical control with acceptable toxicity using contemporary radiotherapy techniques. Hypofractionated radiotherapy and stereotactic body radiation therapy have gained an increasing interest in recent years and they have the potential to become the standard of care even if long-term data about their efficacy and safety are not well established. Strong radiobiological basis supports the use of high dose for fraction in prostate cancer, due to the demonstrated exceptionally low values of α / β . Clinical experiences with hypofractionated and stereotactic radiotherapy (with an adequate biologically equivalent dose) demonstrated good tolerance, a PSA control comparable to conventional fractionation, and the advantage of shorter time period of treatment. This paper reviews the radiobiological findings that have led to the increasing use of hypofractionation in the management of prostate cancer and briefly analyzes the clinical experience in this setting.

  3. Hypofractionated stereotactic body radiotherapy (SBRT) for liver metastases. A retrospective analysis of 74 patients treated in the Klinikum rechts der Isar Munich; Die hypofraktionierte, stereotaktische Strahlentherapie von Lebermetastasen. Eine retrospektive Analyse von 74 Patienten des Klinikums rechts der Isar Muenchen

    Energy Technology Data Exchange (ETDEWEB)

    Heppt, Franz Johannes

    2013-06-12

    Purpose of this study was to evaluate the outcome of stereotactic body radiotherapy (SBRT) of liver metastases and prognostic factors for local control and overall survival. From 2000 to 2009 74 patients with 91 metastases were treated at the Department for Radiation Therapy and Oncology (TU Muenchen). With an observed local control rate of 75% after 1 year, SBRT proved as an effective local treatment option. Unfortunately, systemic tumor progression still dominates long term survival in many patients.

  4. Hypofractionation for prostate cancer.

    Science.gov (United States)

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

    2009-01-01

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

  5. Dosimetry of the stereotactic radiosurgery with linear accelerators equipped with micro multi-blades collimators; Dosimetria dos sistemas de radiocirurgia estereotaxica com aceleradores lineares equipados com colimadores micro multi-laminas

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Andre Mozart de Miranda

    2008-07-01

    model and guarantee its applicability in dosimetric evaluations of radiotherapy with this CLINAC. The geometrical description of the mMLC m3 for Monte Carlo purposes, using the PENELOPE code, was considered satisfactory, providing the characterization of relevant physical parameters such as the transmission of the mMLC, within an estimated uncertainty of {+-} 0,2%, and the average under dose of (11,4 {+-} 2,0)%, due the tongue and groove effect, which is coincident with the experimental value of (12,5 {+-} 2,7)%, for this particular collimator design. The Monte Carlo simulation codes which combine a single source model of the CLINAC 600C with the full m3 model, allows to calculate dose distributions in water for conformal beams within the discrepancy level of {+-} 1%. However, output factors of conformal beams with the mMLC can be calculated with uncertainties varying from 1 to 3%, when they are compared to experimental results. These evaluated fields represent, and come close to treatment fields. The results of this work guarantee a better dosimetric knowledge of the micro multi leaf collimator m3, which is used in three-dimensional stereotactic radiotherapy and radiosurgery techniques. This provides a useful tool in the evaluation of the mMLC as well as the absorbed doses produced in complex field configurations.(author)

  6. Gamma-knife radiosurgery for trigeminal neuralgia

    Energy Technology Data Exchange (ETDEWEB)

    Kannan, V.; Deopujari, C.E.; Misra, B.K.; Shetty, P.G.; Shroff, M.M.; Pendse, A.M. [PD Hinduja National Hospital and Medical Research Centre, Mumbai, (India)

    1999-08-01

    Gamma knife was installed at the PD Hinduja National Hospital and Medical Research Centre, Mumbai, India, in January 1997. In the first year of gamma-knife radiosurgery to January 1998, we treated 110 patients, of whom six had medically refractory trigeminal neuralgia. Seven treatments were administered to this group of six patients (one had bilateral neuralgia). This report evaluates the effectiveness of radiosurgery treatment in these patients. The median age of the patients was 56 years and there were five males and one female. Following Leksell stereotactic frame fixation, a magnetic resonance imaging scan was done in all. The Leksell gamma plan was used for planning. A radiosurgery dose of 70-80 Gy was delivered to the trigeminal root entry zone, 2-4 mm anterior to the junction of the pons and trigeminal nerve with a single 4 mm collimator helmet. Complete pain relief was achieved in four patients. Two had partial relief. No patient developed any radiosurgery related morbidity during the follow-up period of 5-16 months. Radiosurgery seems to be an effective approach for medically or surgically refractory trigeminal neuralgia. Copyright (1999) Blackwell Science Pty Ltd 10 refs., 2 figs.

  7. Robotic Radiosurgery. Treating prostata cancer and related genitourinary applications

    Energy Technology Data Exchange (ETDEWEB)

    Ponsky, Lee E. (ed.) [Case Western Reserve University School of Medicine, Cleveland, OH (United States). University Hospitals Case Medical Center

    2012-07-01

    Prostate cancer is the most common cancer among North American and European men, but its treatment continues to be problematic owing to serious side-effects, including erectile dysfunction, urinary incontinence, and potential lower GI complications. Robotic radiosurgery offers a novel, rapid, non-invasive outpatient treatment option for prostate cancer that combines robotics, advanced image-guided motion detection, and automated real-time corrective spatial positioning with submillimeter precision. This book examines all aspects of the treatment of prostate cancer with robotic radiosurgery. After introductory sections on radiosurgery as a multidisciplinary practice and specific issues relating to prostate cancer, the important challenge posed by prostate motion when administering radiation therapy is examined in depth, with detailed discussion as to how image-guided robotic radiosurgery overcomes this problem by continously identifying the precise location of the prostate throughout the course of treatment. A further major section is devoted to a discussion of techniques and potential radiobiological and clinical advantages of hypofractionated radiation delivery by means of robotic radiosurgery systems. The book closes by discussing other emerging genitourinary applications of robotic radiosurgery. All of the authors are experts in their field who present a persuasive case for this fascinating technique. (orig.)

  8. Efficient and accurate stereotactic radiotherapy using flattening filter free beams and HexaPOD robotic tables

    DEFF Research Database (Denmark)

    Nielsen, Morten; Hansen, C. R.; Brink, C.

    2016-01-01

    Flattening filter free (FFF) high dose rate beam technique was introduced for brain stereotactic radiosurgery (SRS) and lung Stereotactic Body Radiotherapy (SBRT). Furthermore, a HexaPOD treatment table was introduced for the brain SRS to enable correction of rotational setup errors. 19 filter fl...

  9. Conformal Stereotactic Radiosurgery With Multileaf Collimation.

    Science.gov (United States)

    1992-01-01

    R. Virudachalam, D.R. Spelbring, G.T.Y. Chen, "Beam’s eye view based prostate treatment planning: Is it useful?" Int. J. Radiation Oncology Biol...G.T.Y. Chen, "Beam’s eye view based prostate treatment planning: Is it useful?" Int. J. Radiation Oncology Biol. Phys. 19:759 (1990) Lul87 B. Lulu...tbinsum, *bins, *tbins, nbins, nbinsuiu, thk, *aplim, *laljm, *axlim, apmax, apmin, ].amax, lamin, tapi, tap2, tHal, tla2, taxi , tax2, ctap, ctla, ctax

  10. Stereotactic radiosurgery for brain metastasis: Pitie-Salpetriere Hospital experience; Interet de la radiotherapie en condition stereotaxiques (radiochirurgie) des metastases cerebrales: experience et resultats du groupe hospitalier Pitie-Salpetriere

    Energy Technology Data Exchange (ETDEWEB)

    Feuvret, L.; Germain, I.; Cornu, P.; Boisserie, G.; Dormont, D.; Hardiman, C.; Tep, B.; Faillot, T.; Duffau, H.; Simon, J.M.; Dendale, R.; Delattre, J.Y.; Poisson, M.; Marsault, C.; Philippon, J.; Fohanno, D.; Baillet, F.; Mazeron, J.J. [Hopital Pitie-Salpetriere, 75 - Paris (France)

    1998-05-01

    Retrospective analysis of the influence of clinical and technical factors on local control and survival after radiosurgery for brain metastasis. From january 1994 to December 1996, 42 patients presenting with 71 metastases underwent radiosurgery for brain metastasis. The median age was 56 years and the median Karnofsky index 80. Primary sites included: lung (20 patients), kidney (seven), breast (five), colon (two), melanoma (three), osteosarcoma (one) and it was unknown for three patients. Seventeen patients had extracranial metastasis. Twenty-four patients were treated at recurrence which occurred after whole brain irradiation (12 patients), surgical excision (four) or after both treatments (eight). Thirty-six sessions of radiosurgery have been realized for one metastasis and 13 for two, three or four lesions. The median metastasis diameter was 21 mm and the median volume 1.7 cm{sup 3}. The median peripheral dose to the lesion was 14 Gy, and the median dose at the isocenter 20 Gy. Sixty-five metastasis were evaluable for response analysis. The overall local control rate was 82% and the 1-year actuarial rate was 72%. In univariate analysis, theoretical radioresistance (P = 0.001), diameter less than 3 cm (P = 0.039) and initial treatment with radiosurgery (P 0.041) were significantly associated with increased local control. Only the first two factors remained significant in multivariate analysis. No prognostic factor of overall survival was identified. The median survival was 12 months. Six patients had a symptomatic oedema (RTOG grade 2), only one of which requiring a surgical excision. In conclusion, 14 Gy delivered at the periphery of metastasis seems to be a sufficient dose to control most brain metastases, with a minimal toxicity. Better results were obtained for lesions initially treated with radiosurgery, theoretically radioresistant and with a diameter less than 3 cm. (authors)

  11. Extreme Hypofractionated Image-Guided Radiotherapy for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Carlo Greco

    2013-09-01

    Full Text Available An emerging body of data suggests that hypofractionated radiation schedules, where a higher dose per fraction is delivered in a smaller number of sessions, may be superior to conventional fractionation schemes in terms of both tumour control and toxicity profile in the management of adenocarcinoma of the prostate. However, the optimal hypofractionation scheme is still the subject of scientific debate. Modern computer-driven technology enables the safe implementation of extreme hypo fractionation (often referred to as stereotactic body radiation therapy [SBRT]. Several studies are currently being conducted to clarify the yet unresolved issues regarding treatment techniques and fractionation regimens. Recently, the American Society for Radiation Oncology (ASTRO issued a model policy indicating that data supporting the use of SBRT for prostate cancer have matured to a point where SBRT could be considered an appropriate alternative for select patients with low-to-intermediate risk disease. The present article reviews some of the currently available data and examines the impact of tracking technology to mitigate intra-fraction target motion, thus, potentially further improving the clinical outcomes of extreme hypofractionated radiation therapy in appropriately selected prostate cancer patients. The Champalimaud Centre for the Unknown (CCU’s currently ongoing Phase I feasibility study is described; it delivers 45 Gy in five fractions using prostate fixation via a rectal balloon, and urethral sparing via catheter placement with on-line intra-fractional motion tracking through beacon transponder technology.

  12. Hypofractionated SBRT versus conventionally fractionated EBRT for prostate cancer: comparison of PSA slope and nadir

    OpenAIRE

    Anwar, Mekhail; Weinberg, Vivian; Albert J. Chang; Hsu, I-Chow; Roach, Mack; Gottschalk, Alexander

    2014-01-01

    Background Patients with early stage prostate cancer have a variety of curative radiotherapy options, including conventionally-fractionated external beam radiotherapy (CF-EBRT) and hypofractionated stereotactic body radiotherapy (SBRT). Although results of CF-EBRT are well known, the use of SBRT for prostate cancer is a more recent development, and long-term follow-up is not yet available. However, rapid post-treatment PSA decline and low PSA nadir have been linked to improved clinical outcom...

  13. 立体定向放射外科治疗癫痫的剂量-体积与脑水肿的相关性研究%Correlation occurrence of radiation induced encephaledema with target dose and volume in stereotactic radiosurgery of epilepsy

    Institute of Scientific and Technical Information of China (English)

    樊跃飞; 耿明英

    2015-01-01

    目的 研究立体定向放射外科治疗低剂量照射癫痫灶引起的放射性脑水肿与治疗剂量和体积的相关性.方法 回顾性分析1999年10月-2005年5月山东万杰医院及重庆大坪医院γ刀中心治疗的各种类型难治性癫痫患者136例.对136例患者采用立体定向放射治疗的靶区体积和剂量进行对比分析,绘出散点图,并进行相关数据的Logistic回归性分析,得出一定剂量、体积范围内预测放射性脑水肿发生概率的方程.结果 立体定向放射外科的靶区中心剂量> 18 Gy或靶区体积> 30 cm3时,发生放射性脑水肿反应的可能性最大.回归性分析后得到预测方程,经验证该方程的正确率为94.7%.结论 利用靶区体积和剂量作为参数,通过相关性分析得到的方程,可以预测立体定向放射外科治疗癫痫患者后发生放射性脑水肿的概率,该方程有一定的临床参考价值.%Objective To study the correlation between the occurrence of encephaledema and the target dose-volume after the low dose stereotactic radiosurgery of epilepsy.Methods Totally 136 epilepsy patients treated by low dose stereotactic radiosurgery with Novalis System were analysed retrospectively.The target doses and volumes of the patients were analysed by drawing out the scatterplot and conducting the binary Logistic regression to all of the data.An equation was obtained to predict the occurrence of radiation induced encephaledema in certain range of target volume and dose.Results Among all of 136 patients,different degree of local encephaledema occurred in 19 cases after the radiosurgery.Higher occurrence of radiation induced encephaledema was observed when the target central dose (i.e.90% isodose circling the target)was more than 18 Gy or the target volume more than 30 cm3.Moreover,in patients with multitargets the doses of different targets devoted to each other,which could lead to the occurrence of local encephaledema.The equation to

  14. QUALITY ASSURANCE OF 4D-CT SCAN TECHNIQUES IN MULTICENTER PHASE III TRIAL OF SURGERY VERSUS STEREOTACTIC RADIOTHERAPY (RADIOSURGERY OR SURGERY FOR OPERABLE EARLY STAGE (STAGE 1A) NON-SMALL-CELL LUNG CANCER [ROSEL] STUDY)

    NARCIS (Netherlands)

    Hurkmans, Coen W.; van Lieshout, Maarten; Schuring, Danny; van Heumen, Marielle J. T.; Cuijpers, Johan P.; Lagerwaard, Frank J.; Widder, Joachim; van der Heide, Uulke A.; Senan, Suresh

    2011-01-01

    Purpose: To determine the accuracy of four-dimensional computed tomography (4D-CT) scanning techniques in institutions participating in a Phase III trial of surgery vs. stereotactic radiotherapy (SBRT) for lung cancer. Methods and Materials: All 9 centers performed a 4D-CT scan of a motion phantom (

  15. Hypofractionation for clinically localized prostate cancer.

    Science.gov (United States)

    Cabrera, Alvin R; Lee, W Robert

    2013-07-01

    This manuscript reviews the clinical evidence for hypofractionation in prostate cancer, focusing on data from prospective trials. For the purposes of this manuscript, we categorize hypofractionation as moderate (2.4-4 Gy per fraction) or extreme (6.5-10 Gy per fraction). Five randomized controlled trials have evaluated moderate hypofractionation in >1500 men, with most followed for >4-5 years. The results of these randomized trials are inconsistent. No randomized trials or other rigorous comparisons of extreme hypofractionation with conventional fractionation have been reported. Prospective single-arm studies of extreme hypofractionation appear favorable, but small sample sizes preclude precise estimates of efficacy and short follow-up prevents complication estimates beyond 3-5 years. Over the next several years, the results of 3 large noninferiority trials of moderate hypofractionation and 2 randomized trials of extreme hypofractionation should help clarify the role of hypofractionation in prostate cancer therapy.

  16. Contemporary methods of radiosurgery treatment with the Novalis linear accelerator system.

    Science.gov (United States)

    Chen, Joseph C T; Rahimian, Javad; Girvigian, Michael R; Miller, Michael J

    2007-01-01

    Radiosurgery has emerged as an indispensable component of the multidisciplinary approach to neoplastic, functional, and vascular diseases of the central nervous system. In recent years, a number of newly developed integrated systems have been introduced for radiosurgery and fractionated stereotactic radiotherapy treatments. These modern systems extend the flexibility of radiosurgical treatment in allowing the use of frameless image-guided radiation delivery as well as high-precision fractionated treatments. The Novalis linear accelerator system demonstrates adequate precision and reliability for cranial and extracranial radiosurgery, including functional treatments utilizing either frame-based or frameless image-guided methods.

  17. Gamma Knife® radiosurgery for trigeminal neuralgia.

    Science.gov (United States)

    Yen, Chun-Po; Schlesinger, David; Sheehan, Jason P

    2011-11-01

    Trigeminal neuralgia is characterized by a temporary paroxysmal lancinating facial pain in the trigeminal nerve distribution. The prevalence is four to five per 100,000. Local pressure on nerve fibers from vascular loops results in painful afferent discharge from an injured segment of the fifth cranial nerve. Microvascular decompression addresses the underlying pathophysiology of the disease, making this treatment the gold standard for medically refractory trigeminal neuralgia. In patients who cannot tolerate a surgical procedure, those in whom a vascular etiology cannot be identified, or those unwilling to undergo an open surgery, stereotactic radiosurgery is an appropriate alternative. The majority of patients with typical facial pain will achieve relief following radiosurgical treatment. Long-term follow-up for recurrence as well as for radiation-induced complications is required in all patients undergoing stereotactic radiosurgery for trigeminal neuralgia.

  18. Radiosurgery for brain metastases and cerebral edema.

    Science.gov (United States)

    Gazit, Inbal; Har-Nof, Sagi; Cohen, Zvi R; Zibly, Zion; Nissim, Uzi; Spiegelmann, Roberto

    2015-03-01

    The objective of this study was to assess reduction in cerebral edema following linear accelerator radiosurgery (LINAC) as first line therapy for brain metastasis. We reviewed the medical records of all patients who underwent LINAC radiosurgery for brain metastasis at our institution during 2010-2012, and who had not previously undergone either surgery or whole brain radiotherapy. Data were analyzed for 55 brain metastases from 46 patients (24 males), mean age 59.9 years. During the 2 months following LINAC radiosurgery, the mean steroid dose decreased from 4.8 to 2.6 mg/day, the mean metastasis volume decreased from 3.79±4.12 cc to 2.8±4.48 cc (p=0.001), and the mean edema volume decreased from 16.91±30.15 cc to 12.85±24.47 cc (p=0.23). The 17 patients with reductions of more than 50% in brain edema volume had single metastases. Edema volume in the nine patients with two brain metastases remained stable in five patients (volume change 10%, 2-14 cc). In a subanalysis of eight metastases with baseline edema volume greater than 40 cc, edema volume decreased from 77.27±37.21 cc to 24.84±35.6 cc (p=0.034). Reductions in brain edema were greater in metastases for which non-small-cell lung carcinoma and breast cancers were the primary diseases. Overall, symptoms improved in most patients. No patients who were without symptoms or who had no signs of increased intracranial pressure at baseline developed signs of intracranial pressure following LINAC radiosurgery. In this series, LINAC stereotactic radiosurgery for metastatic brain lesions resulted in early reduction in brain edema volume in single metastasis patients and those with large edema volumes, and reduced the need for steroids.

  19. Compensating for Quasi-periodic Motion in Robotic Radiosurgery

    CERN Document Server

    Ernst, Floris

    2012-01-01

    Compensating for Quasi-periodic Motion in Robotic Radiosurgery outlines the techniques needed to accurately track and compensate for respiratory and pulsatory motion during robotic radiosurgery. The algorithms presented within the book aid in the treatment of tumors that move during respiration. In Chapters 1 and 2,  the book introduces the concept of stereotactic body radiation therapy, motion compensation strategies and the clinical state-of-the-art. In Chapters 3 through 5, the author describes and evaluates new methods for motion prediction, for correlating external motion to internal organ motion, and for the evaluation of these algorithms’ output based on an unprecedented amount of real clinical data. Finally, Chapter 6 provides a brief introduction into currently investigated, open questions and further fields of research. Compensating for Quasi-periodic Motion in Robotic Radiosurgery targets researchers working in the related fields of surgical oncology, artificial intelligence, robotics and more. ...

  20. Linear accelerator radiosurgery for arteriovenous malformations: Updated literature review.

    Science.gov (United States)

    Yahya, S; Heyes, G; Nightingale, P; Lamin, S; Chavda, S; Geh, I; Spooner, D; Cruickshank, G; Sanghera, P

    2017-04-01

    Arteriovenous malformations (AVMs) are the leading causing of intra-cerebral haemorrhage. Stereotactic radiosurgery (SRS) is an established treatment for arteriovenous malformations (AVM) and commonly delivered using Gamma Knife within dedicated radiosurgery units. Linear accelerator (LINAC) SRS is increasingly available however debate remains over whether it offers an equivalent outcome. The aim of this project is to evaluate the outcomes using LINAC SRS for AVMs used within a UK neurosciences unit and review the literature to aid decision making across various SRS platforms. Results have shown comparability across platforms and strongly supports that an adapted LINAC based SRS facility within a dynamic regional neuro-oncology department delivers similar outcomes (in terms of obliteration and toxicity) to any other dedicated radio-surgical platform. Locally available facilities can facilitate discussion between options however throughput will inevitably be lower than centrally based dedicated national radiosurgery units.

  1. Stereotactic multiple are radiotherapy. IV--Haemangioblastoma.

    Science.gov (United States)

    Chakraborti, P R; Chakrabarti, K B; Doughty, D; Plowman, P N

    1997-04-01

    Our initial experience in the treatment of haemangioblastoma using conventional external beam radiotherapy and stereotactic radiotherapy (radiosurgery), by the linear accelerator method, is reported. Six haemangioblastomas in five patients were treated with a mean follow-up of 40 months (range 14-60). Five haemangioblastomas in four patients were treated with stereotactic radiotherapy, where four showed complete radiological response and the fifth was static. Neurological symptoms and signs improved in those patients. The sixth haemangioblastoma was situated close to the pituitary and optic chiasm, and was treated with conventionally fractionated external beam radiotherapy. The lesion showed partial response. No complications were noted in this patient group. This series complements and extends the relatively sparse published literature demonstrating that radiotherapy is an effective option for treating haemangioblastomas. Radiosurgery often lends itself particularly well to these discrete lesions allowing highly focused treatment. For patients with multiple and metachronous cerebellar haemangioblastomas as part of the von Hipple-Lindau syndrome, the data support a policy of conventionally fractionated external beam radiotherapy to the whole cerebellum of 50-55 Gy followed, after a period of time, by radiosurgery to persisting lesions (patients 3 and 4).

  2. Role of Adjuvant Radiosurgery after Thoracoscopic Microsurgical Resection of a Spinal Schwannoma

    Directory of Open Access Journals (Sweden)

    Toba N. Niazi

    2012-01-01

    Full Text Available Stereotactic radiosurgery to benign tumors of the spine has not been advocated as a primary treatment modality because of the favorable prognosis for these lesions after gross-total resection. There is even less evidence regarding its use as an adjuvant to neurosurgical resection of benign recurrent spinal disease. We describe the case of a 30-year-old man with a thoracic spinal schwannoma who had an interval increase of his lesion five months after thoracoscopic microsurgical resection. The patient opted for noninvasive stereotactic radiosurgery in lieu of additional surgical excision and has had stable disease 15 months after radiosurgical treatment with the linear accelerator (LINAC system. In this setting, stereotactic radiosurgery provided a useful adjunct to thoracoscopic microsurgical resection. Future Class I and II evidence should be sought to evaluate the utility of stereotactic radiosurgery as a primary treatment modality or as an adjuvant for microneurosurgical resection of benign spinal lesions in patients who want noninvasive treatment after disease recurrence or who harbor medical comorbidities that would preclude them from being safe surgical candidates.

  3. CyberKnife radiosurgery: Precision without incision

    Directory of Open Access Journals (Sweden)

    Enja Siva Prasad Reddy

    2015-01-01

    Full Text Available CyberKnife stereotactic radiosurgery system is an innovative, effective, frameless, non-invasive substitute for conventional surgical treatment of cancer. It works on the principle of stereotaxy. It is used for the treatment of both cancerous and non-cancerous tumors, intracranial lesions, tumors of lung, spine, prostate, and kidney, recurrent cases of oral squamous cell carcinoma, arteriovenous malformation, and trigeminal neuralgia. It has an advantage over other systems like Gamma knife radiosurgery and linear accelerator (LINAC-based systems, as it is frameless, has submillimeter accuracy, does not affect the normal cells adjacent to the lesion, and tracks the lesion in synchronization with the patient′s respiratory rate. The future of CyberKnife encompasses possibilities such as incremental improvements in accuracy and better shaping of the field of radiation and would certainly allow extension of radiosurgery as an effective substitute for chemotherapy. This paper aims to review and highlight the immense potential that CyberKnife holds in the field of dentistry in treating disorders of the head and neck region, thereby ensuring enhanced longevity for the patients.

  4. Dosimetric accuracy of a staged radiosurgery treatment

    Science.gov (United States)

    Cernica, George; de Boer, Steven F.; Diaz, Aidnag; Fenstermaker, Robert A.; Podgorsak, Matthew B.

    2005-05-01

    For large cerebral arteriovenous malformations (AVMs), the efficacy of radiosurgery is limited since the large doses necessary to produce obliteration may increase the risk of radiation necrosis to unacceptable levels. An alternative is to stage the radiosurgery procedure over multiple stages (usually two), effectively irradiating a smaller volume of the AVM nidus with a therapeutic dose during each session. The difference between coordinate systems defined by sequential stereotactic frame placements can be represented by a translation and a rotation. A unique transformation can be determined based on the coordinates of several fiducial markers fixed to the skull and imaged in each stereotactic coordinate system. Using this transformation matrix, isocentre coordinates from the first stage can be displayed in the coordinate system of subsequent stages allowing computation of a combined dose distribution covering the entire AVM. The accuracy of this approach was tested on an anthropomorphic head phantom and was verified dosimetrically. Subtle defects in the phantom were used as control points, and 2 mm diameter steel balls attached to the surface were used as fiducial markers and reference points. CT images (2 mm thick) were acquired. Using a transformation matrix developed with two frame placements, the predicted locations of control and reference points had an average error of 0.6 mm near the fiducial markers and 1.0 mm near the control points. Dose distributions in a staged treatment approach were accurately calculated using the transformation matrix. This approach is simple, fast and accurate. Errors were small and clinically acceptable for Gamma Knife radiosurgery. Accuracy can be improved by reducing the CT slice thickness.

  5. Dosimetric accuracy of a staged radiosurgery treatment

    Energy Technology Data Exchange (ETDEWEB)

    Cernica, George [Department of Physics, State University of New York at Buffalo, Buffalo, NY 14263 (United States); Boer, Steven F de [Department of Radiation Oncology, Roswell Park Cancer Institute and the State University of New York at Buffalo, Buffalo, NY 14263 (United States); Diaz, Aidnag [Department of Radiation Oncology, Roswell Park Cancer Institute and the State University of New York at Buffalo, Buffalo, NY 14263 (United States); Fenstermaker, Robert A [Department of Neurosurgery, Roswell Park Cancer Institute and the State University of New York at Buffalo, Buffalo, NY 14263 (United States); Podgorsak, Matthew B [Department of Radiation Oncology, Roswell Park Cancer Institute and the State University of New York at Buffalo, Buffalo, NY 14263 (United States)

    2005-05-07

    For large cerebral arteriovenous malformations (AVMs), the efficacy of radiosurgery is limited since the large doses necessary to produce obliteration may increase the risk of radiation necrosis to unacceptable levels. An alternative is to stage the radiosurgery procedure over multiple stages (usually two), effectively irradiating a smaller volume of the AVM nidus with a therapeutic dose during each session. The difference between coordinate systems defined by sequential stereotactic frame placements can be represented by a translation and a rotation. A unique transformation can be determined based on the coordinates of several fiducial markers fixed to the skull and imaged in each stereotactic coordinate system. Using this transformation matrix, isocentre coordinates from the first stage can be displayed in the coordinate system of subsequent stages allowing computation of a combined dose distribution covering the entire AVM. The accuracy of this approach was tested on an anthropomorphic head phantom and was verified dosimetrically. Subtle defects in the phantom were used as control points, and 2 mm diameter steel balls attached to the surface were used as fiducial markers and reference points. CT images (2 mm thick) were acquired. Using a transformation matrix developed with two frame placements, the predicted locations of control and reference points had an average error of 0.6 mm near the fiducial markers and 1.0 mm near the control points. Dose distributions in a staged treatment approach were accurately calculated using the transformation matrix. This approach is simple, fast and accurate. Errors were small and clinically acceptable for Gamma Knife radiosurgery. Accuracy can be improved by reducing the CT slice thickness.

  6. Role of the Technical Aspects of Hypofractionated Radiation Therapy Treatment of Prostate Cancer: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, Stefania, E-mail: clemente_stefania@libero.it [Istituto di Ricovero e Cura a Carattere Scientifico Centro di Riferimento Oncologico della Basilicata Rionero in Vulture, Potenza (Italy); Nigro, Roberta [Azienda Sanitaria Locale Rieti, Roma (Italy); Oliviero, Caterina [Istituto di Ricovero e Cura a Carattere Scientifico Centro di Riferimento Oncologico della Basilicata Rionero in Vulture, Potenza (Italy); Marchioni, Chiara [Azienda Sanitaria Locale Rieti, Roma (Italy); Esposito, Marco [Azienda Sanitaria, Firenze (Italy); Giglioli, Francesca Romana [Azienda Ospedaliera Città della Salute e della Scienza di Torino, Torino (Italy); Mancosu, Pietro [Humanitas Clinical and Research Hospital, Rozzano, Milano (Italy); Marino, Carmelo [Humanitas Centro Catanese di Oncologia, Catania (Italy); Russo, Serenella [Azienda Sanitaria, Firenze (Italy); Stasi, Michele [Azienda Ospedaliera Ordine Mauriziano di Torino, Torino (Italy); Strigari, Lidia [Istituto Nazionale Tumori Regina Elena, Roma (Italy); Veronese, Ivan [Universita' degli Studi di Milano, Milano (Italy); Landoni, Valeria [Istituto Nazionale Tumori Regina Elena, Roma (Italy)

    2015-01-01

    The increasing use of moderate (<35 fractions) and extreme (<5 fractions) hypofractionated radiation therapy in prostate cancer is yielding favorable results, both in terms of maintained biochemical response and toxicity. Several hypofractionation (HF) schemes for the treatment of prostate cancer are available, although there is considerable variability in the techniques used to manage intra-/interfraction motion and deliver radiation doses. We performed a review of the published studies on HF regimens as a topic of interest for the Stereotactic Ablative Radiotherapy working group, which is part of the Italian Association of Medical Physics. Aspects of organ motion management (imaging for contouring, target volume definition, and rectum/bladder preparation) and treatment delivery (prostate localization, image guided radiation therapy strategy and frequency) were evaluated and categorized to assess outcome relative to disease control and toxicity. Despite the heterogeneity of the data, some interesting trends that emerged from the review might be useful in identifying an optimum HF strategy.

  7. CyberKnife stereotactic radiotherapy as monotherapy for low- to intermediate-stage prostate cancer: Early experience, feasibility, and tolerance

    NARCIS (Netherlands)

    S. Aluwini (Shafak); P.H. van Rooij (Peter); M.S. Hoogeman (Mischa); C.H. Bangma (Chris); W.J. Kirkels (Wim); L. Incrocci (Luca); I.-K.K. Kolkman-Deurloo (Inger-Karina)

    2010-01-01

    textabstractPurpose: The CyberKnife (CK), a linear accelerator mounted on a robotic device, enables excellent dose conformation to the target and minimizes dose to surrounding normal tissue. It is a very suitable device for performing hypofractionated stereotactic body radiotherapy as monotherapy fo

  8. Advances of The Pathogenesis of Trigeminal Neuralgia and The Efifciency of Stereotactic Radiosurgery%三叉神经痛的发病机制及立体定向放射外科治疗进展

    Institute of Scientific and Technical Information of China (English)

    潘绵顺; 李勇; 邱书珺

    2015-01-01

    Trigeminal neuralgia (TN) is a debilitating pain syndrome within the trigeminal nerve distribution, that is characterized by agonizing, paroxysmal and lancinating pain. The pathophysiology of trigeminal neuralgia is not clear and no satisfactory animal model so far. But with the rapid development of pathophysiology and neuroimaging, there are some evidences showed that the central nervous and peripheral nerve factors may cause trigeminal neuralgia attacks. The recommended ifrst-line treatment for TN is medical therapy, but this often fails to provide pain relief. Thus, secondline treatment modalities are given to patients whose symptoms are intractable or who cannot tolerate medication. These treatment modalities include invasive procedures such as microvascular decompression (MVD), and ablative procedures such as radiosurgery, percutaneous balloon microcompression, radiofrequency rhizotomy and glycerol rhizolysis. Among them, gamma knife and CyberKnife radiosurgery have becoming an important method in the treatment of TN because of its’ minimally invasive and signiifcant efifciency.%三叉神经痛是指在三叉神经分布区内反复发作的阵发性剧烈疼痛。其发病机制是一个非常复杂的病理过程,至今没有满意的动物模型,制约了其病因学的研究,随着病理生理及神经影像学的发展,有越来越多的证据表明:中枢神经因素及外周神经因素均可导致三叉神经痛的发作。三叉神经痛的一线治疗方案是药物治疗,如卡马西平或奥卡西平等;但对于不耐受药物副作用或是药物难治性TN可选择二线治疗,如微血管减压术,立体定向放射外科,经皮穿刺微球囊压迫术,射频或甘油注射三叉神经阻断术。其中,以伽玛刀和射波刀为代表的立体定向放射外科因创伤性极小,且疗效显著成为TN患者治疗的重要方法。

  9. The long term effect of X-knife stereotactic radiosurgery on the residual pituitary adenomas after surgery%X线立体定向放射外科治疗术后残留垂体腺瘤远期疗效分析

    Institute of Scientific and Technical Information of China (English)

    孙红; 孟庆勇; 陈小妹; 陈先平; 董东

    2013-01-01

    .5% ). There was no death, no serious complication and no hypopituitarism; moreover, 13 of the total 35 patients with visual disorder got obvious improvement of sight. Conclusion X - knife stereotactic radiosurgery is an effective method in the treatment of residual pituitary adenomas.

  10. Extreme hypofractionation for early prostate cancer: Biology meets technology.

    Science.gov (United States)

    De Bari, Berardino; Arcangeli, Stefano; Ciardo, Delia; Mazzola, Rosario; Alongi, Filippo; Russi, Elvio G; Santoni, Riccardo; Magrini, Stefano M; Jereczek-Fossa, Barbara A

    2016-11-01

    The aim of this review is to present the available radiobiological, technical and clinical data about extreme hypofractionation in primary prostate cancer radiotherapy. The interest in this technique is based on the favourable radiobiological characteristics of prostate cancer and supported by advantageous logistic aspects deriving from short overall treatment time. The clinical validity of short-term treatment schedule is proven by a body of non-randomised studies, using both isocentric (LINAC-based) or non-isocentric (CyberKnife(®)-based) stereotactic body irradiation techniques. Twenty clinical studies, each enrolling more than 40 patients for a total of 1874 treated patients, were revised in terms of technological setting, toxicity, outcome and quality of life assessment. The implemented strategies for the tracking of the prostate and the sparing of the rectal wall have been investigated with particular attention. The urinary toxicity after prostate stereotactic body irradiation seems slightly more pronounced as compared to rectal adverse events, and this is more evident for late occurring events, but no worse as respect to conventional fractionation schemes. As far as the rate of severe acute toxicity is concerned, in all the available studies the treatment was globally well tolerated. While awaiting long-term data on efficacy and toxicity, the analysed studies suggest that the outcome profile of this approach, alongside the patient convenience and reduced costs, is promising. Forty-eight ongoing clinical trials are also presented as a preview of the expectation from the near future.

  11. 大分割放疗联合替莫唑胺治疗大体积脑转移瘤的前瞻性临床研究%Efficacy of hypofractionated stereotactic radiotherapy combined with temozolomide for large brain metastases:a prospective clinical study

    Institute of Scientific and Technical Information of China (English)

    马玉超; 邓垒; 王文卿; 易俊林; 李晔雄; 肖建平; 毕楠; 刘峰; 刘笛; 赵瑞芝; 刘清峰; 张烨; 王凯

    2016-01-01

    目的:前瞻性Ⅱ期临床研究分析大分割放疗联合替莫唑胺( TMZ)治疗大体积脑转移瘤的疗效及安全性。方法2010—2015年共33例患者纳入研究,疗前、后中位KPS分别为70、80分,原发灶主要为NSCLC (58%)。脑转移瘤直径≥3 cm或体积≥6 cm3,放疗剂量52 Gy分13次或52.5 Gy分15次,同步TMZ 75 mg/m2/d,辅助TMZ 6周期(150 mg/m2,第1—5天,28天为1周期)。治疗中复查MRI,如瘤体积缩小≥20%则缩野。疗后2~3个月复查MRI评估疗效。结果总治疗病灶及大体积病灶数分别为95个及38个,>10 cm324例(63%),中位GTV 15.3 cm3(5.7~142.8 cm3)。22例(67%)实现疗中缩野,中位GTV缩小率为44%(21%~88%)。中位总剂量为59.5 Gy,同步和辅助TMZ完成率分别为100%和21%。全组客观反应率为97%,1年LC、颅内PFS、OS分别为97%、70%、62%,中位生存期15.3个月。主要不良反应为1—2级恶心、呕吐,1例出现3级肝功能损伤。结论大分割放疗联合TMZ治疗大体积脑转移瘤安全有效,50%以上患者可实现疗中缩野,缩短治疗时间,减少损伤。临床试验注册 ClinicalTrials.gov,注册号:NCT02654106。%Objective To analyze the efficacy and safety of hypofractionated stereotactic radiotherapy ( FSRT ) combined with temozolomide ( TMZ ) for large brain metastases ( BMs ) in a prospective phaseⅡclinical trial.Methods From 2010 to 2015, a total of 33 patients were enrolled as subjects.The median Karnofsky Performance Status scores before and after treatment were 70 and 80, respectively.The major primary tumor was non-small cell lung cancer (57.6%).The brain metastasis had a diameter of≥3 cm or a volume of ≥6 cm3 .The radiation dose was 52 Gy in 13 fractions or 52.2 Gy in 15 fractions.Patients received TMZ at a dose of 75 mg/m2 per day concurrently.The radiotherapy was followed by 6 cycles of adjuvant

  12. De novo superior cerebellar artery aneurysm following radiosurgery for trigeminal neuralgia.

    Science.gov (United States)

    Chen, Joseph C T; Chao, Kuo; Rahimian, Javad

    2017-04-01

    Stereotactic radiosurgery is a commonly used method for treatment of trigeminal neuralgia. Radiation has been known to be a factor in the later development of aneurysms. Aneurysms have been reported to occur after radiation delivered in a variety of methods including both externally delivered radiation radiosurgery and brachytherapy. We report here an incidence of a de novo aneurysm presenting following radiosurgery treatment for trigeminal neuralgia. The patient was treated using frame-based LINAC radiosurgery receiving 90Gy to the mid cisternal extent of the nerve via a 4mm conical collimator. The patient presented with progressive hypoesthesia 11years after treatment. Imaging evaluation demonstrated the presence of an aneurysm abutting the treated trigeminal nerve. The aneurysm was successfully coil embolized. The patient's facial hypoesthesia, however, did not improve following embolization. We believe that this is the first report of such an aneurysm occurring after radiosurgery for trigeminal neuralgia. De novo aneurysms are a recognized long term complication of radiotherapy and radiosurgery treatment. This report shows such aneurysms can occur with very small treatment volumes. Late sensory changes following radiosurgery for trigeminal neuralgia should prompt workup for de novo aneurysms as well as other late adverse radiation effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Immune Modulation and Stereotactic Radiation: Improving Local and Abscopal Responses

    Directory of Open Access Journals (Sweden)

    Jing Zeng

    2013-01-01

    Full Text Available New and innovative treatment strategies for cancer patients in the fields of immunotherapy and radiotherapy are rapidly developing in parallel. Among the most promising preclinical treatment approaches is combining immunotherapy with radiotherapy where early data suggest synergistic effects in several tumor model systems. These studies demonstrate that radiation combined with immunotherapy can result in superior efficacy for local tumor control. More alluring is the emergence of data suggesting an equally profound systemic response also known as “abscopal” effects with the combination of radiation and certain immunotherapies. Studies addressing optimal radiation dose, fractionation, and modality to be used in combination with immunotherapy still require further exploration. However, recent anecdotal clinical reports combining stereotactic or hypofractionated radiation regimens with immunotherapy have resulted in dramatic sustained clinical responses, both local and abscopal. Technologic advances in clinical radiation therapy has made it possible to deliver hypofractionated regimens anywhere in the body using stereotactic radiation techniques, facilitating further clinical investigations. Thus, stereotactic radiation in combination with immunotherapy agents represents an exciting and potentially fruitful new space for improving cancer therapeutic responses.

  14. Gamma knife radiosurgery for arteriovenous malformations located in eloquent regions of the brain

    Directory of Open Access Journals (Sweden)

    Javalkar Vijayakumar

    2009-12-01

    Full Text Available Background : Stereotactic radiosurgery is an effective treatment strategy for selected group of patients with cerebral arteriovenous malformations (AVMs. Aim : The aim of this study was to evaluate the obliteration rates, complications, and patient outcomes after Gamma knife radiosurgery for cerebral arteriovenous malformations (AVMs located in eloquent regions of the brain with an emphasis on neurological morbidity. Materials and Methods : Between 2000 and December 2005, 37 patients with AVMs in eloquent locations (sensory, motor, speech, visual cortex, basal ganglia, and brain stem underwent stereotactic radiosurgery. We retrospectively reviewed the clinical data of these patients to asses the outcomes. Of the 37 patients, only two patients had prior embolization. Three underwent prospective staged volume radiosurgery. Two patients needed redo-radiosurgery for residual AVM. Mean target volume was 9.1 cc. Three lesions had nidus volume more than 20 cc. Average marginal dose was 18.75 Gy. The median duration of follow-up was 23 months (range, 6-60 months. 15 patients had follow-up of more than 36 months. Results : A total of 15 patients had follow-up of more than 36 months, thus available for evaluation of angiographic obliteration rates. Complete angiographic obliteration was documented in seven patients (46.7%. Four patients experienced hemorrhage during the latency period. One patient who had subsequent hemorrhage on follow-up developed worsening of neurological deficit. One patient developed significant sensory symptoms which resolved after steroids. No additional clinical deterioration related to treatment was noted in rest of the patients. Conclusions : AVMs located in eloquent and in deep locations can be treated safely with stereotactic radiosurgery with acceptable obliteration rates and minimal morbidity.

  15. Dynamic gamma knife radiosurgery.

    Science.gov (United States)

    Luan, Shuang; Swanson, Nathan; Chen, Zhe; Ma, Lijun

    2009-03-21

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C and Perfexion units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can obtain a family of plans representing a tradeoff between the delivery time and the dose

  16. Dynamic gamma knife radiosurgery

    Science.gov (United States)

    Luan, Shuang; Swanson, Nathan; Chen, Zhe; Ma, Lijun

    2009-03-01

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C™ and Perfexion™ units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can obtain a family of plans representing a tradeoff between the delivery time and the

  17. Dynamic gamma knife radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Luan Shuang; Swanson, Nathan; Chen Zhe [Department of Computer Science, University of New Mexico, Albuquerque, NM 87131 (United States); Ma Lijun [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94143 (United States)], E-mail: sluan@cs.unm.edu, E-mail: nate@cs.unm.edu, E-mail: zchen@cs.unm.edu, E-mail: lijunma@radonc.ucsf.edu

    2009-03-21

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can

  18. Intracranial radiosurgery: an effective and disruptive innovation in neurosurgery.

    Science.gov (United States)

    Niranjan, Ajay; Madhavan, Ravindranath; Gerszten, Peter C; Lunsford, L Dade

    2012-01-01

    Physicians are guided by the teachings of their chosen field, standards of accepted practice, peer pressure, prior training, and other sources of bias. When potential bias begins to impact recommendations for care in the field of tumor management, physicians may fail to realize the importance of emerging medical innovations. Some of these ultimately turn out to be 'disruptive innovations.' These innovations are more often than not both low risk and cost effective. But the leaders in the field often initially ignore these newer technologies in favor of more mature existing technologies. However, over time these technologies gradually improve and become mainstream management practices. Intracranial radiosurgery is one such innovation which was not embraced by the neurosurgical community in the beginning. Nowadays, a wide variety of brain and body disorders are treated with radiosurgery. Acoustic neuromas and brain metastases are examples of rapidly growing indications of radiosurgery. In this report, the authors describe the emergence of stereotactic radiosurgery as a disruptive innovation in the field of medicine.

  19. Linear accelerator radiosurgery for trigeminal neuralgia: case report

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyong Geun [Dongguk University International Hospital, Goyang (Korea, Republic of)

    2006-06-15

    Trigeminal neuralgia is defined as an episodic electrical shock-like sensation in a dermatomal distribution of the trigeminal nerve. When medications fail to control pain, various procedures are used to attempt to control refractory pain. Of available procedures, stereotactic radiosurgery is the least invasive procedure and has been demonstrated to produce significant pain relief with minimal side effects. Recently, linear accelerators were introduced as a tool for radiosurgery of trigeminal neuralgia beneath the already accepted gamma unit. Author have experienced one case with trigeminal neuralgia treated with linear accelerator. The patient was treated with 85 Gy by means of 5 mm collimator directed to trigeminal nerve root entry zone. The patient obtained pain free without medication at 20 days after the procedure and remain pain free at 6 months after the procedure. He didn't experience facial numbness or other side effects.

  20. A halo-ring technique for fractionated stereotactic radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Clark, B.G.; Podgorsak, E.B.; Souhami, L.; Caron, J.-L.; Sixel, K.E. (Montreal General Hospital, PQ (Canada)); Olivier, A. (Montreal Neurological Inst., PQ (Canada). Dept. of Neurosurgery)

    1993-06-01

    Stereotactic radiosurgery has become established as an effective treatment modality for certain non-malignant brain diseases such as arteriovenous malformations. This paper describes an extension of the authors' linear accelerator-based radiosurgical technique to fractionated treatment of intracranial disease. The fractionated stereotactic radiotherapy technique expands the use of the modality by sparing normal cells within the treatment volume thus improving the therapeutic ratio. The first treatment is given using a stereotactic frame both for target localization and patient immobilization. The frame is then removed and subsequent treatments use a standard neurosurgical halo-ring for patient immobilization. The halo-ring is left in place on the skull for the duration of the course of treatment. They describe a sensitive and effective technique for checking the rotational beam parameters and collimator alignment which is used immediately prior to treatment to ensure adequate accuracy of dose delivery to the target volume. (author).

  1. Stereotactic body radiation therapy for the primary treatment of localized prostate cancer

    OpenAIRE

    Oliai, Caspian; Lanciano, Rachelle; Sprandio, Brian; Yang, Jun; Lamond, John; Arrigo, Steven; Good, Michael; Mooreville, Michael; Garber, Bruce; Brady, Luther W.

    2012-01-01

    Objective The low alpha/beta ratio of prostate cancer suggests that hypofractionated schemes of dose-escalated radiotherapy should be advantageous. We report our experience using stereotactic body radiation therapy (SBRT) for the primary treatment of prostate cancer to assess efficacy and toxicity. Methods From 2007 to 2010, 70 patients (51 % low risk, 31 % intermediate risk, and 17 % high risk) with localized prostate cancer were treated with SBRT using the CyberKnife system. One-third of pa...

  2. The 2009 devaluation of radiosurgery and its impact on the neurosurgery-radiation oncology partnership.

    Science.gov (United States)

    Heilbrun, M Peter; Adler, John R

    2010-07-01

    Neurosurgeons, radiation oncologists, and, increasingly, other surgical specialists recognize that radiosurgery is an important tool for managing selected disorders throughout the body. The partnership between neurosurgeons and radiation oncologists has resulted in collaborative studies that have established the clinical benefits of radiosurgery. Today, however, a range of political and financial issues is straining this relationship and thereby undermining the practice of radiosurgery. Neurosurgeons and radiation oncologists recently restricted the definition of radiosurgery to include only cranial- and spine-focused radiation treatments. Meanwhile, organized radiation oncology decided unilaterally that radiosurgery administered to other parts of the body would be termed stereotactic body radiation therapy. Finally, neurosurgical and radiation oncology coding experts developed new Current Procedural Terminology codes for cranial vault and spine radiosurgery, which were approved for use by the Relative Value Scale Update Committee as of 2009. The authors suggest that the neurosurgery strategy-which included 1) reasserting that all of the tasks of a radiosurgery procedure remain bundled, and 2) agreeing to limit the definition of radiosurgery to cranial vault and spine-has failed neurosurgeons who perform radiosurgery, and it may jeopardize patient access to this procedure in the future. The authors propose that all of the involved medical specialties recognize that the application of image-guided, focused radiation therapy throughout the body requires a partnership between radiation and surgical disciplines. They also urge surgeons to reexamine their coding methods, and they maintain that Current Procedural Terminology codes should be consistent across all of the different specialties involved in these procedures. Finally, surgeons should consider appropriate training in medical physics and radiobiology to perform the tasks involved in these specific procedures

  3. Severe hypofractionation: Non-homogeneous tumour dose delivery can counteract tumour hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Ruggieri, Ruggero; Naccarato, Stefania (Medical Physics Dept., Inst. Scientifico Romagnolo per lo Studio e la Cura dei Tumori, Meldola, FC (Italy)), E-mail: ruggieri.ruggero@gmail.com; Nahum, Alan E. (Physics Dept., Clatterbridge Centre for Oncology, Bebington CH63 4JY (United Kingdom))

    2010-11-15

    Background. The current rationale for severely hypofractionated schedules (3-5 fractions) used in stereotactic-body-radiotherapy (SBRT) of non-small-cell lung cancer (NSCLC) is the small size of the irradiated volumes. Being the dose prescribed to the 60-80% isodose line enclosing the PTV, a non-homogeneous tumour-dose-delivery results which might impact on tumour hypoxia. A comparison between homogeneous and SBRT-like non-homogeneous tumour-dose-delivery is then proposed here, using severe hypofractionation on large tumour volumes where both dose prescription strategies are applicable. Materials and methods. For iso-NTCP hypofractionated schedules (1f/d5d/w) with respect to standard fractionation (d=2Gy), computed from the individual DVHs for lungs, oesophagus, heart and spinal cord (Lyman-Kutcher-Burman NTCP-model), TCP values were calculated (a-averaged Poissonian-LQ model) for homogeneous and SBRT-like non-homogeneous plans both with and without tumour hypoxia. Two different estimates of the oxygen-enhancement-ratio (OER) in combination with two distinct assumptions on the kinetics of reoxygenation were considered. Homogeneous and SBRT-like non-homogeneous plans were finally compared in terms of therapeutic ratio (TR), as the product of TCP and the four (1-NTCPi) values. Results. For severe hypofractionation (3-5 fractions) and for any of the hypotheses on the kinetics of reoxygenation and the OER, there was a significant difference between the computed TRs with or without inclusion of tumour hypoxia (anova, p=0.01) for homogeneous tumour-dose-delivery, but no significant difference for the SBRT-like non-homogeneous one. Further, a significantly increased mean TR for the group of SBRT-like non-homogeneous plans resulted (t-test, p=0.05) with respect to the group with homogeneous target-dose-coverage. Conclusions. SBRT-like dose-boosting seems to counterbalance the loss of reoxygenation within a few fractions. For SBRT it then seems that, in addition to the high

  4. [Treatment of choroid melanoma by Gamma-Knife radiosurgery].

    Science.gov (United States)

    Devin, F; Regis, J; Berros, P; Manera, L; Porcheron, D; Sedan, R; Peragut, J C; Saracco, J B

    1996-01-01

    Conservative treatment of uveal melanomas by Gamma Knife Radiosurgery is based on the use of cross fire technique with 201 Cobalt60 sources. A following of 13 months is available for the first case operated by Gamma-Knife Surgery in France. Technical baselines and one year preliminary results are reported. The diagnosis of uveal melanoma T3NOMO was established by converging results of clinical examination, angiography and echography. The definition of the target was based on stereotactic MRT examination. We delivered a dose of 50 Gys to the marginal isodose (50%). Today, one year after treatment the tumor decreased, the visual function was preserved. There were no side effect or complication.

  5. Spinal radiosurgery - efficacy and safety after prior conventional radiotherapy

    Directory of Open Access Journals (Sweden)

    Nikolajek Katharina

    2011-12-01

    Full Text Available Abstract Background Conventional external beam radiotherapy is a standard procedure for treatment of spinal metastases. In case of progression spinal cord tolerance limits further radiotherapy in pre-irradiated areas. Spinal stereotactic radiotherapy is a non-invasive option to re-treat pre-irradiated patients. Nevertheless, spinal radiosurgery results in relevant dose deposition within the myelon with potential toxicity. Aim of the study was to retrospectively analyse the efficacy and feasibility for salvage radiosurgery of spinal metastases. Methods During a period of 4 years (2005-2009 70 lesions in 54 patients were treated in 60 radiosurgery sessions and retrospectively analysed. Clinical (pain, sensory and motor deficit and radiological (CT/MRI follow-up data were collected prospectively after radiosurgery. Pain - as main symptom - was classified by the Visual Analogue Scale (VAS score. Every patient received single session radiosurgery after having been treated first-line with conventionally fractionated radiotherapy. Kaplan-Meier method and life tables were used to analyse freedom from local failure and overall survival. Results At a median follow-up of 14.5 months the actuarial rates of freedom from local failure at 6/12/18 months were 93%, 88% and 85%, respectively. The median radiosurgery dose was 1 × 18 Gy (range 10-28 Gy to the median 70% isodose. The VAS score of patients with pain (median 6 dropped significantly (median 4, p = 0.002. In 6 out of 7 patients worse sensory or motor deficit after SRS was caused by local or distant failures (diagnosed by CT/MRI. One patient with metastatic renal cell carcinoma developed a progressive complete paraparesis one year after the last treatment at lumbar level L3. Due to multiple surgery and radiosurgery treatments at the lumbar region and further local progression, the exact reason remained unclear. Apart from that, no CTC grade III or higher toxicity has been observed. Conclusions By

  6. Tolerance of cranial nerves of the cavernous sinus to radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Tishler, R.B.; Loeffler, J.S.; Alexander, E. III; Kooy, H.M. (Harvard Medical School, Boston, MA (United States)); Lunsford, L.D.; Duma, C.; Flickinger, J.C. (Univ. of Pittsburgh Medical Center, PA (United States))

    1993-09-20

    Stereotactic radiosurgery is becoming a more accepted treatment option for benign, deep seated intracranial lesions. However, little is known about the effects of large single fractions of radiation on cranial nerves. This study was undertaken to assess the effect of radiosurgery on the cranial nerves of the cavernous sinus. The authors examined the tolerance of cranial nerves (II-VI) following radiosurgery for 62 patients (42/62 with meningiomas) treated for lesions within or near the cavernous sinus. Twenty-nine patients were treated with a modified 6 MV linear accelerator (Joint Center for Radiation Therapy) and 33 were treated with the Gamma Knife (University of Pittsburgh). Three-dimensional treatment plans were retrospectively reviewed and maximum doses were calculated for the cavernous sinus and the optic nerve and chiasm. Median follow-up was 19 months (range 3-49). New cranial neuropathies developed in 12 patients from 3-41 months following radiosurgery. Four of these complications involved injury to the optic system and 8 (3/8 transient) were the result of injury to the sensory or motor nerves of the cavernous sinus. There was no clear relationship between the maximum dose to the cavernous sinus and the development of complications for cranial nerves III-VI over the dose range used (1000-4000 cGy). For the optic apparatus, there was a significantly increased incidence of complications with dose. Four of 17 patients (24%) receiving greater than 800 cGy to any part of the optic apparatus developed visual complications compared with 0/35 who received less than 800 cGy (p = 0.009). Radiosurgery using tumor-controlling doses of up to 4000 cGy appears to be a relatively safe technique in treating lesions within or near the sensory and motor nerves (III-VI) of the cavernous sinus. The dose to the optic apparatus should be limited to under 800 cGy. 21 refs., 4 tabs.

  7. Overall quality control in radiosurgery; Control de calidad global en radiocirugia

    Energy Technology Data Exchange (ETDEWEB)

    Banos Capilla, M. C.; Garcia Martinez, M. a.; Bea Gilbert, J.; Ros Garcia, L.; Gil Deltoro, P.

    2011-07-01

    Quality Control dosimetric and geometric is essential to ensure good treatment in stereotactic radiosurgery. Furthermore, the development of new diagnostic tools CT, MRI, fusion of both) and treatment (micromultilaminas, etc.) Allows increased accuracy thereof, and at the same time. requires a thorough quality control. Currently, the most complete and thorough is the use of dummies which are made multimodal image scans, where different plan dosimetry and radiate in the treatment unit with the relevant detector array.

  8. Image-guided stereotactic radiotherapy for patients with vestibular schwannoma. A clinical study

    Energy Technology Data Exchange (ETDEWEB)

    Badakhshi, H.; Muellner, S.; Budach, V. [Charite School of Medicine and University Hospital of Berlin, Departments for Radiation Oncology, Berlin (Germany); Wiener, E. [School of Medicine and University Hospital of Berlin, Institute for Neuroradiology, Berlin (Germany)

    2014-06-15

    Local tumor control and functional outcome after linac-based stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) for vestibular schwannoma (VS) were assessed. In all, 250 patients with VS were treated: 190 patients with tumors < 2 cm diameter underwent SRS and 60 patients with tumors >2 to 3.5 cm underwent FSRT. Dose prescription for all cases with SRS (n = 190, 76 %) was 13.5 Gy. For FSRT, mainly two hypofractionated schedules (n = 60, 24 %) with either 7 fractions of 5 Gy (total dose: 35 Gy; n = 35) or 11 fractions of 3.8 Gy (total dose: 41.8 Gy; n = 16) were used. The primary endpoint was local tumor control. Secondary endpoints were symptomatic control and morbidity. The median follow-up was 33.8 months. The 3-year local tumor control was 88.9 %. Local control for SRS and FSRT was 88 and 92 %, respectively. For FSRT with 35 and 41.8 Gy, local control was 90 and 100 %, respectively. There were no acute reactions exceeding grade I. In 61 cases (24.4 % of the entire cohort), trigeminal neuralgia was reported prior to treatment. At last follow-up, 16.3 % (10/61) of those patients reported relief of pain. Regarding facial nerve dysfunction, 45 patients (18 %) presented with symptoms prior to RT. At the last follow-up, 13.3% (6/45) of those patients reported a relief of dysesthesia. Using SRS to treat small VS results in good local control rates. FSRT for larger lesions also seems effective. Severe treatment-related complications are not frequent. Therefore, image-guided stereotactic radiotherapy is an appropriate alternative to microsurgery for patients with VS. (orig.) [German] Wir analysierten die lokale Kontrolle und die funktionellen Verlaeufe bei Patienten mit einem Vestibularisschwannom (VS), die sich einer linacbasierten stereotaktischen Radiochirurgie (SRS) oder einer fraktionierten stereotaktischen Radiotherapie (FSRT) unterzogen. Zwischen 1998 und 2008 wurden 250 Patienten mit einem VS behandelt. In dieser Kohorte wurden 190

  9. Stereotactic Irradiation of GH-Secreting Pituitary Adenomas

    Directory of Open Access Journals (Sweden)

    G. Minniti

    2012-01-01

    Full Text Available Radiotherapy (RT is often employed in patients with acromegaly refractory to medical and/or surgical interventions in order to prevent tumour regrowth and normalize elevated GH and IGF-I levels. It achieves tumour control and hormone normalization up to 90% and 70% of patients at 10–15 years. Despite the excellent tumour control, conventional RT is associated with a potential risk of developing late toxicity, especially hypopituitarism, and its role in the management of patients with GH-secreting pituitary adenomas remains a matter of debate. Stereotactic techniques have been developed with the aim to deliver more localized irradiation and minimize the long-term consequences of treatment, while improving its efficacy. Stereotactic irradiation can be given in a single dose as stereotactic radiosurgery (SRS or in multiple doses as fractionated stereotactic radiotherapy (FSRT. We have reviewed the recent published literature on stereotactic techniques for GH-secreting pituitary tumors with the aim to define the efficacy and potential adverse effects of each of these techniques.

  10. Spine radiosurgery for the local treatment of spine metastases: Intensity-modulated radiotherapy, image guidance, clinical aspects and future directions

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Fabio Ynoe de; Neves-Junior, Wellington Furtado Pimenta; Hanna, Samir Abdallah; Carvalho, Heloisa de Andrade [Hospital Sirio-Libanes, Sao Paulo, SP (Brazil). Departamento de Radioterapia; Taunk, Neil Kanth; Yamada, Yoshiya [Memorial Sloan Kettering Cancer Center, Department of Radiation Oncology, New York, NY (United States); Laufer, Ilya, E-mail: fymoraes@gmail.com [Memorial Sloan Kettering Cancer Center, Department of Neurosurgery, New York, NY (United States)

    2016-02-15

    Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and non randomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future. (author)

  11. Stereotactic (Mammographically Guided) Breast Biopsy

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Stereotactic Breast Biopsy Stereotactic breast biopsy uses mammography – a specific type ... Breast Biopsy? What is Stereotactic (Mammographically Guided) Breast Biopsy? Lumps or abnormalities in the breast are often ...

  12. Gamma Knife radiosurgery for hemangioma of the cavernous sinus.

    Science.gov (United States)

    Lee, Cheng-Chia; Sheehan, Jason P; Kano, Hideyuki; Akpinar, Berkcan; Martinez-Alvarez, Roberto; Martinez-Moreno, Nuria; Guo, Wan-Yuo; Lunsford, L Dade; Liu, Kang-Du

    2017-05-01

    OBJECTIVE Cavernous sinus hemangiomas (CSHs) are rare vascular tumors. A direct microsurgical approach usually results in massive hemorrhage and incomplete tumor resection. Although stereotactic radiosurgery (SRS) has emerged as a therapeutic alternative to microsurgery, outcome studies are few. Authors of the present study evaluated the role of SRS for CSH. METHODS An international multicenter study was conducted to review outcome data in 31 patients with CSH. Eleven patients had initial microsurgery before SRS, and the other 20 patients (64.5%) underwent Gamma Knife SRS as the primary management for their CSH. Median age at the time of radiosurgery was 47 years, and 77.4% of patients had cranial nerve dysfunction before SRS. Patients received a median tumor margin dose of 12.6 Gy (range 12-19 Gy) at a median isodose of 55%. RESULTS Tumor regression was confirmed by imaging in all 31 patients, and all patients had greater than 50% reduction in tumor volume at 6 months post-SRS. No patient had delayed tumor growth, new cranial neuropathy, visual function deterioration, adverse radiation effects, or hypopituitarism after SRS. Twenty-four patients had presented with cranial nerve disorders before SRS, and 6 (25%) of them had gradual improvement. Four (66.7%) of the 6 patients with orbital symptoms had symptomatic relief at the last follow-up. CONCLUSIONS Stereotactic radiosurgery was effective in reducing the volume of CSH and attaining long-term tumor control in all patients at a median of 40 months. The authors' experience suggests that SRS is a reasonable primary and adjuvant treatment modality for patients in whom a CSH is diagnosed.

  13. Stereotactic radiation therapy of brain metastases from colorectal cancer: A single institution cohort.

    Science.gov (United States)

    Paix, A; Antoni, D; Adeduntan, R; Noël, G

    2017-05-01

    The brain remains an uncommon site of colorectal cancer metastases. Due to the improvement of overall colorectal cancer patient survival, the incidence of brain metastases will likely rise. We report the efficacy and safety of hypofractionnated stereotactic radiation therapy and stereotactic radiosurgery, and its role in colorectal cancer brain metastasis management. Between June 2010 and December 2014, fifteen consecutive patients received hypofractionnated stereotactic radiation therapy or stereotactic radiosurgery as first local therapy or following surgical removal for colorectal cancer brain metastases. The primary endpoint was overall survival. Secondary endpoints were brain progression free survival, in field control rates and safety. Median follow-up was 41 months (95% confidence interval [CI]: [8.9-73.1 months]), median overall survival was 8 months (95% CI [4.7-11.3 months]), and median brain progression-free survival was 5 months (95% CI [3.9-6.1 months]). Five in field recurrences were observed, which makes a control rate per metastases at 6 and 12 months of 77.8% (95% CI [74.34%-81.26%]), 51.9% (95% CI [44.21%-59.59%]) respectively. Over the 19 treatment sequences, five in field recurences were observed: 6, 12 and 18 months control rate per treatment sequence were 93.3% (95% CI [90.42%-96.18%]), 68.1% (95% CI [62.03%-74.17%]) and 45.4% (95% CI [36.14%-54.66%]) respectively. Immediate tolerance was good with no toxicity grade III or more. Long-term toxicity included two radionecrosis among which, one was symptomatic. The results of this retrospective analysis suggest that hypofractionnated stereotactic radiation therapy and stereotactic radiosurgery are effective and safe treatment modalities for single and multiple small brain metastases from colorectal cancer. However, results need to be confirmed by multicenter, collected data. Copyright © 2017. Published by Elsevier SAS.

  14. Plan Quality and Treatment Efficiency for Radiosurgery to Multiple Brain Metastases: Non-Coplanar RapidArc vs. Gamma Knife

    OpenAIRE

    Liu, Haisong; Andrews, David W.; Evans, James J.; Werner-Wasik, Maria; Yan YU; Dicker, Adam Paul; Shi, Wenyin

    2016-01-01

    Objectives This study compares the dosimetry and efficiency of two modern radiosurgery [stereotactic radiosurgery (SRS)] modalities for multiple brain metastases [Gamma Knife (GK) and LINAC-based RapidArc/volumetric modulated arc therapy], with a special focus on the comparison of low-dose spread. Methods Six patients with three or four small brain metastases were used in this study. The size of targets varied from 0.1 to 10.5 cc. SRS doses were prescribed according to the size of ...

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Milano, M. [University of Rochester Medical Center (United States)

    2015-06-15

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

  17. Stereotactic Radiosurgery in Treating Patients With Brain Tumors

    Science.gov (United States)

    2012-03-21

    Adult Central Nervous System Germ Cell Tumor; Adult Malignant Meningioma; Adult Medulloblastoma; Adult Noninfiltrating Astrocytoma; Adult Oligodendroglioma; Adult Craniopharyngioma; Adult Meningioma; Brain Metastases; Adult Ependymoma; Adult Pineal Parenchymal Tumor; Adult Brain Stem Glioma; Adult Infiltrating Astrocytoma; Mixed Gliomas; Stage IV Peripheral Primitive Neuroectodermal Tumor

  18. Hypofractionation for prostate cancer: a critical review.

    Science.gov (United States)

    Miles, Edward F; Lee, W Robert

    2008-01-01

    In ideal circumstances, the fractionation schedule of radiotherapy should match the fractionation sensitivity of the tumor relative to the nearby normal tissues. A number of recent publications have suggested that the alpha-beta ratio (alpha/beta) for prostate is low, in the range of 1 to 3 Gy. If alpha/beta is truly low, then hypofractionated schedules using fewer, larger fractions should improve the therapeutic ratio. This critical review examines the clinical experience with hypofractionation. Several prospective trials indicate that toxicity is limited with sophisticated dose delivery and compact clinical target volume to planning target volume margins, but the single-arm nature of these trials precludes definitive statements on efficacy. Several large randomized trials comparing conventional fractionation to hypofractionation are ongoing and are described. Until these trials are completed and the results submitted for rigorous peer review, the notion that alpha/beta for prostate cancer is low remains an unconfirmed hypothesis.

  19. Clinical outcomes of gamma knife radiosurgery in the salvage treatment of patients with recurrent high-grade glioma.

    Science.gov (United States)

    Elaimy, Ameer L; Mackay, Alexander R; Lamoreaux, Wayne T; Demakas, John J; Fairbanks, Robert K; Cooke, Barton S; Lamm, Andrew F; Lee, Christopher M

    2013-12-01

    Previously published randomized evidence did not report a survival advantage for patients diagnosed with grade IV glioma who were treated with stereotactic radiosurgery followed by external beam radiation therapy and chemotherapy when compared to patients treated with external beam radiation therapy and chemotherapy alone. In recent years, gamma knife radiosurgery has become increasingly popular as a salvage treatment modality for patients diagnosed with recurrent high-grade glioma. The purpose of this article is to review the efficacy of gamma knife radiosurgery for patients who suffer from this malignancy. Retrospective, prospective, and randomized clinical studies published between the years 2000 and 2012 analyzing gamma knife radiosurgery for patients with high-grade glioma were reviewed. After assessing patient age, Karnofsky performance status, tumor histology, and extent of resection, gamma knife radiosurgery is a viable, minimally invasive treatment option for patients diagnosed with recurrent high-grade glioma. The available prospective and retrospective evidence suggests that gamma knife radiosurgery provides patients with a high local tumor control rate and a median survival after tumor recurrence ranging from 13 to 26 months. Gamma knife radiosurgery followed by chemotherapy for recurrent high-grade glioma may provide select patients with increased levels of survival. However, further investigation into this matter is needed due to the limited number of published reports. Additional clinical research is also needed to analyze the efficacy and radiation-related toxicities of fractionated gamma knife radiosurgery due to its potential to limit treatment-associated morbidity. Gamma knife radiosurgery is a safe and effective treatment option for select patients diagnosed with recurrent high-grade glioma. Although treatment outcomes have improved, further evidence in the form of phase III randomized trials is needed to assess the durability of treating

  20. [The come-back of hypofractionation?].

    Science.gov (United States)

    Cosset, Jean-Marc

    2005-11-01

    Hypofractionation (i.e. the use of fewer higher fractional doses than usual) is not a new concept. It had actually been proposed in the early year of Radiotherapy by the German and Austrian specialists. In the seventy's, supported by the - wrong - hypotheses which gave birth to the NSD (Nominal Standard Dose), hypofractionation reappears. The consequential increase of late complications which was observed led the radiation oncologists to give up again using large doses per fraction, except for a few specific situations, such as palliative treatments. We are recently facing a new "come-back" of hypofractionation, in particular for breast and prostate cancers. In the case of breast cancer, the aim is clearly to look for more "convenience" for both the patients and the physicians, proposing shorter irradiation schedules including a lesser number of fractions. Some "modestly" hypofractionated schemes have been proposed and used, without apparently altering the efficacy/toxicity ratio, but these results have been seriously questioned. As for prostate cancer, the situation is different, since in that case new radiobiological data are at the origin of the newly proposed hypofractionation schedules. A number of papers actually strongly suggested that the fractionation sensitivity of prostate cancer could be higher than the one of the tissues responsible for late toxicity (i.e the exact opposite of the classical dogma). Based on those data, several hypofractionated schemes have been proposed, with a few preliminary results looking similar to the ones obtained by the classical schedules. However, no randomised study is available so far, and a few recent radiobiological data are now questioning the new dogma of the high fractionation sensitivity of prostate cancer. For those two - frequent - cancers, it seems therefore that prudence should prevail before altering classical irradiation schedules which have proven their efficacy, while staying open to new concepts and proposing

  1. Multi-institutional Registry for Prostate Cancer Radiosurgery: An Observational Clinical Trial

    Directory of Open Access Journals (Sweden)

    Debra eFreeman

    2015-01-01

    Full Text Available Title: Multi-institutional Registry for Prostate Cancer Radiosurgery: An Observational Clinical TrialAuthors: Debra Freeman, MD*; Gregg Dickerson, MD; Mark Perman, MDObjective: To report on the design, methodology and early outcome results of a multi-institutional registry study of prostate cancer radiosurgery.Methods: The Registry for Prostate Cancer Radiosurgery (RPCR was established in 2010 to further evaluate the efficacy and toxicity of prostate radiosurgery (SBRT for the treatment of clinically localized prostate cancer. Men with prostate cancer were asked to voluntarily participate in the Registry. Demographic, baseline medical and treatment-related data were collected and stored electronically in a HIPAA-compliant database, maintained by Advertek, Inc. Enrolled men were asked to complete short, multiple choice questionnaires regarding their bowel, bladder and sexual function. Patient-reported outcome forms were collected at baseline and at regular intervals (every 3-6 months following treatment. Serial PSA measurements were obtained at each visit and included in the collected data.Results: From July 2010 to July 2013, nearly 2000 men from 45 participating sites were enrolled in the registry. The majority (86% received radiosurgery as monotherapy. At 2 years follow-up, biochemical disease free survival was 92%. No Grade 3 late urinary toxicity was reported. One patient developed Grade 3 gastrointestinal toxicity (rectal bleeding. Erectile function was preserved in 80% of men <70 yeats old. Overall compliance with data entry was 64%.Conclusion: Stereotactic radiosurgery is an alternative option to conventional radiotherapy for the treatment of organ-confined prostate cancer. The Registry for Prostate Cancer Radiosurgery represents the collective experience of multiple institutions, including community-based cancer centers, with outcome results in keeping with published, prospective trials of prostate SBRT.

  2. Gamma knife radiosurgery of meningiomas involving the foramen magnum

    Science.gov (United States)

    Starke, Robert M.; Nguyen, James H.; Reames, Davis L.; Rainey, Jessica; Sheehan, Jason P.

    2010-01-01

    Background: Foramen magnum meningiomas represent a challenging clinical entity. Although resection is performed for those with a mass effect, complete resection is not always feasible. For some patients, stereotactic radiosurgery may be used as the primary treatment modality. We evaluatedthe long-term outcome of Gamma Knife radiosurgery (GKRS) for the treatment of patientswith a foramen magnum meningioma. Materials and Methods: Between 1991 and 2005, 222 patients with a meningioma in the posterior fossa were treated with GKRS at the University of Virginia. Of these patients, 5 had meningiomas involving the foramen magnum. At the time of GKRS, the median age of the patients was 60 years (range, 51–78). Three patients were treated with radiosurgery following an initial resection and 2 were treated with upfront radiosurgery. The patients were assessed clinically and radiologically at routine intervals following GKRS. Results: The median tumor volume was 6.8 cc (range 1.9–17 cc). The GKRS tumor received a marginal dose of 12 Gy (range 10–15), and the median number of isocenters was 5 (range 3–19). The mean follow-up was 6 years (range 4–13). One lesion increased in size following GKRS requiring a second treatment, resulting in size stabilization. At the time of the last follow-up, all meningiomas had either demonstrated no growth (n = 4) or reduction in size (n = 1). No patients experienced post-radiotherapy complications. Conclusions: GKRS affords a high rate of tumor control and preservation of neurologic function for patients with foramen magnum meningiomas. Further study of its role in the neurosurgical management of such patients seems warranted. PMID:20890411

  3. Gamma knife radiosurgery of meningiomas involving the foramen magnum

    Directory of Open Access Journals (Sweden)

    R M Starke

    2010-01-01

    Full Text Available Background: Foramen magnum meningiomas represent a challenging clinical entity. Although resection is performed for those with a mass effect, complete resection is not always feasible. For some patients, stereotactic radiosurgery may be used as the primary treatment modality. We evaluatedthe long-term outcome of Gamma Knife radiosurgery (GKRS for the treatment of patientswith a foramen magnum meningioma. Materials and Methods: Between 1991 and 2005, 222 patients with a meningioma in the posterior fossa were treated with GKRS at the University of Virginia. Of these patients, 5 had meningiomas involving the foramen magnum. At the time of GKRS, the median age of the patients was 60 years (range, 51-78. Three patients were treated with radiosurgery following an initial resection and 2 were treated with upfront radiosurgery. The patients were assessed clinically and radiologically at routine intervals following GKRS. Results: The median tumor volume was 6.8 cc (range 1.9-17 cc. The GKRS tumor received a marginal dose of 12 Gy (range 10-15, and the median number of isocenters was 5 (range 3-19. The mean follow-up was 6 years (range 4-13. One lesion increased in size following GKRS requiring a second treatment, resulting in size stabilization. At the time of the last follow-up, all meningiomas had either demonstrated no growth (n = 4 or reduction in size (n = 1. No patients experienced post-radiotherapy complications. Conclusions: GKRS affords a high rate of tumor control and preservation of neurologic function for patients with foramen magnum meningiomas. Further study of its role in the neurosurgical management of such patients seems warranted.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Sook; Kim, Won Woo; Park, In Hwan; Kim, Hee Jong; Lee, Eun Jin; Jung, Jae Hoon [Research Center for Radiotherapy, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Cho, Lawrence Chin Soo; Song, Chang W. [Dept. of Radiation Oncology, University of Minnesota Medical School, Minneapolis (United States)

    2015-12-15

    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.

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

    Science.gov (United States)

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

    2013-10-01

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

  6. Hypofractionated whole breast radiotherapy: current perspectives

    Directory of Open Access Journals (Sweden)

    Koulis TA

    2015-10-01

    Full Text Available Theodora A Koulis, Tien Phan, Ivo A Olivotto Department of Oncology, University of Calgary, Tom Baker Cancer Centre, Calgary, AB, Canada Abstract: Adjuvant radiotherapy (RT is an important part of breast cancer management but the dose and fractionation schedules used are variable. A total of 50 Gy in 25 daily fractions delivered over 5 weeks is often considered the "standard" adjuvant RT prescription. Hypofractionated regimes such as 42.5 Gy in 16 daily fractions or 40 Gy in 15 daily fractions following breast-conserving surgery have proven to be equally effective and achieve similar or better cosmetic and normal tissue outcomes for both invasive and in situ diseases and when treating the regional nodes. Hypofractionation is more convenient for patients and less costly. However, certain patients at higher risk of RT late effects may benefit from a less intense, even more extended fractionation schedule. This review describes the indications for whole breast hypofractionated adjuvant RT for patients with breast cancer following breast-conserving surgery and proposes that hypofractionation should be the new "standard" for adjuvant breast cancer RT. Keywords: fractionation, breast cancer, cosmesis, radiotherapy

  7. Setup verification in linac-based radiosurgery.

    Science.gov (United States)

    Falco, T; Lachaine, M; Poffenbarger, B; Podgorsak, E B; Fallone, B G

    1999-09-01

    A semi-automatic technique for the direct setup alignment of radiosurgical circular fields from an isocentric linac to treatment room laser cross-hairs is described. Alignment is achieved by acquiring images of the treatment room positioning laser cross-hairs superimposed on the radiosurgical circular field image. An alignment algorithm calculates the center of the radiosurgical field image as well as the intersection of the laser cross-hairs. This determines any alignment deviations and the information is then used to translate the radiosurgical collimator to its correct aligned position. Two detectors, each being sensitive to the lasers and ionizing radiation, were used to acquire the radiation/laser images. The first detector consists of a 0.3-mm-thick layer of photoconducting a-Se deposited on a 1.5-mm-thick copper plate and the second is film. The algorithm and detector system can detect deviations with a precision of approximately 0.04 mm. A device with gyroscopic degrees of freedom was built in order to firmly hold the detector at any orientation perpendicular to the radiosurgical beam axis. This device was used in conjunction with our alignment algorithm to quantify the isocentric sphere relative to the treatment room lasers over all gantry and couch angles used in dynamic stereotactic radiosurgery.

  8. Extracranial stereotactic radiotherapy: evaluation of PTV coverage and dose conformity.

    Science.gov (United States)

    Hädinger, Ulrich; Thiele, Wibke; Wulf, Jörn

    2002-01-01

    During the past few years the concept of cranial stereotactic radiotherapy has been successfully extended to extracranial tumoral targets. In our department, hypofractionated treatment of tumours in lung, liver, abdomen, and pelvis is performed in the Stereotactic Body Frame (ELEKTA Instrument AB) since 1997. We present the evaluation of 63 consecutively treated targets (22 lung, 21 liver, 20 abdomen/pelvis) in 58 patients with respect to dose coverage of the planning target volume (PTV) as well as conformity of the dose distribution. The mean PTV coverage was found to be 96.3% +/- 2.3% (lung), 95.0% +/- 4.5% (liver), and 92.1% +/- 5.2% (abdomen/pelvis). For the so-called conformation number we obtained values of 0.73 +/- 0.09 (lung), 0.77 +/- 0.10 (liver), and 0.70 +/- 0.08 (abdomen/pelvis). The results show that highly conformal treatment techniques can be applied also in extracranial stereotactic radiotherapy. This is primarily due to the relatively simple geometrical shape of most of the targets. Especially lung and liver targets turned out to be approximately spherically/cylindrically shaped, so that the dose distribution can be easily tailored by rotational fields.

  9. Absence of toxicity with hypofractionated 3-dimensional radiation therapy for inoperable, early stage non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Vuong Te

    2006-11-01

    Full Text Available Abstract Purpose Hypofractionated radiotherapy may overcome repopulation in rapidly proliferating tumors such as lung cancer. It is more convenient for the patients and reduces health care costs. This study reports our results on patients with medically inoperable, early stage, non-small cell lung cancer (NSCLC treated with hypofractionation. Materials and methods Stage T1-2N0 NSCLC patients were treated with hypofractionation alone, 52.5 Gy/15 fractions, in 3 weeks, with 3-dimensional conformal planning. T1-2N1 patients with the hilar lymphnode close to the primary tumor were also eligible for this treatment. We did not use any approach to reduce respiratory motion, but it was monitored in all patients. Elective nodal radiotherapy was not performed. Routine follow up included assessment for acute and late toxicity and radiological tumor response. Median follow up time was 29 months for the surviving patients. Results Thirty-two patients with a median age of 76 years, T1 = 15 and T2 = 17, were treated. Median planning target volume (PTV volume was 150cc and median V16 of both lungs was 13%. The most important finding of this study is that toxicity was minimal. Two patients had grade ≤ 2 acute pneumonitis and 3 had mild (grade 1 acute esophagitis. There was no late toxicity. Actuarial 1 and 2-year overall survival rates are 78% and 56%, cancer specific survival rates (CSS are 90% and 74%, and local relapse free survival rates are 93% and 76% respectively. Conclusion 3-D planning, involved field hypofractionation at a dose of 52.5 Gy in 15 daily fractions is safe, well tolerated and easy radiation treatment for medically inoperable lung cancer patients. It shortens by half the traditional treatment. Results compare favorably with previously published studies. Further studies are needed to compare similar technique with other treatments such as surgery and stereotactic radiotherapy.

  10. Intracranial radiosurgery in the Netherlands. A planning comparison of available systems with regard to physical aspects and workload.

    Science.gov (United States)

    Schoonbeek, A; Monshouwer, R; Hanssens, P; Raaijmakers, E; Nowak, P; Marijnissen, J P A; Lagerwaard, F J; Cuijpers, J P; Vonk, E J A; van der Maazen, R W M

    2010-06-01

    Different planning and treatment systems for intracranial stereotactic radiosurgery available in the Netherlands are compared. The systems for intracranial radiosurgery include: Gamma Knife, Cyberknife, Novalis, and Tomotherapy. Electronic data of 5 patients was transferred to all participating centres and treatment plans were generated according to 2 different prescription protocols. For this study, plans were also generated for a conventional linac. Even systems with a high resolution (Gammaknife and Novalis) have conformity indices in violation with RTOG guidelines (CI > 2.5) when target volumes of 1 cc), all systems perform well. The workload of the different techniques was comparable although the treatment times were usually longer for Gamma Knife radiosurgery. We conclude that small targets should be treated by dedicated systems, larger volumes (> 0.5-1 cc) can also be treated using conventional treatment systems equipped with a MLC.

  11. Analytical calculation of central-axis dosimetric data for a dedicated 6-MV radiosurgery linear accelerator.

    Science.gov (United States)

    Yang, James N; Pino, Ramiro

    2008-10-01

    Narrow beams are extensively used in stereotactic radiosurgery. The accuracy of treatment planning dose calculation depends largely on how well the dosimetric data are measured during the machine commissioning. Narrow beams are characterized by the lack of lateral electronic equilibrium. The lateral electronic disequilibrium in the radiation field and detector's finite size are likely to compromise the accuracy in dose measurements in these beams. This may have a profound impact on outcome in patients who undergo stereotactic radiosurgery. To confirm the measured commissioning data for a dedicated 6-MV linear accelerator-based radiosurgery system, we developed an analytical model to calculate the narrow photon beam central-axis dose. This model is an extension of a previously reported method of Nizin and Mooij for the calculation of the absorbed dose under lateral electronic disequilibrium conditions at depth of dmax or greater. The scatter factor and tissue-maximum ratio were calculated for narrow beams using the parametrized model and compared to carefully measured results for the same beams. For narrow beam radii ranging from 0.2 to 1.5 cm, the differences between the analytical and measured scatter factors were no greater than 1.4%. In addition, the differences between the analytical and measured tissue-maximum ratios were within 3.3% for regions greater than the maximum dose depth. The estimated error of this analytical calculation was less than 2%, which is sufficient to validate measurement results.

  12. Single-session Gamma Knife radiosurgery for optic pathway/hypothalamic gliomas.

    Science.gov (United States)

    El-Shehaby, Amr M N; Reda, Wael A; Abdel Karim, Khaled M; Emad Eldin, Reem M; Nabeel, Ahmed M

    2016-12-01

    OBJECTIVE Because of their critical and central location, it is deemed necessary to fractionate when considering irradiating optic pathway/hypothalamic gliomas. Stereotactic fractionated radiotherapy is considered safer when dealing with gliomas in this location. In this study, the safety and efficacy of single-session stereotactic radiosurgery for optic pathway/hypothalamic gliomas were reviewed. METHODS Between December 2004 and June 2014, 22 patients with optic pathway/hypothalamic gliomas were treated by single-session Gamma Knife radiosurgery. Twenty patients were available for follow-up for a minimum of 1 year after treatment. The patients were 5 to 43 years (median 16 years) of age. The tumor volume was 0.15 to 18.2 cm(3) (median 3.1 cm(3)). The prescription dose ranged from 8 to 14 Gy (median 11.5 Gy). RESULTS The mean follow-up period was 43 months. Five tumors involved the optic nerve only, and 15 tumors involved the chiasm/hypothalamus. Two patients died during the follow-up period. The tumors shrank in 12 cases, remained stable in 6 cases, and progressed in 2 cases, thereby making the tumor control rate 90%. Vision remained stable in 12 cases, improved in 6 cases, and worsened in 2 cases in which there was tumor progression. Progression-free survival was 83% at 3 years. CONCLUSIONS The initial results indicate that single-session Gamma Knife radiosurgery is a safe and effective treatment option for optic pathway/hypothalamic gliomas.

  13. Fractionated radiosurgery for painful spinal metastases: DOSIS - a phase II trial.

    Science.gov (United States)

    Guckenberger, Matthias; Hawkins, Maria; Flentje, Michael; Sweeney, Reinhart A

    2012-11-19

    One third of all cancer patients will develop bone metastases and the vertebral column is involved in approximately 70% of these patients. Conventional radiotherapy with of 1-10 fractions and total doses of 8-30 Gy is the current standard for painful vertebral metastases; however, the median pain response is short with 3-6 months and local tumor control is limited with these rather low irradiation doses. Recent advances in radiotherapy technology - intensity modulated radiotherapy for generation of highly conformal dose distributions and image-guidance for precise treatment delivery - have made dose-escalated radiosurgery of spinal metastases possible and early results of pain and local tumor control are promising. The current study will investigate efficacy and safety of radiosurgery for painful vertebral metastases and three characteristics will distinguish this study. 1) A prognostic score for overall survival will be used for selection of patients with longer life expectancy to allow for analysis of long-term efficacy and safety. 2) Fractionated radiosurgery will be performed with the number of treatment fractions adjusted to either good (10 fractions) or intermediate (5 fractions) life expectancy. Fractionation will allow inclusion of tumors immediately abutting the spinal cord due to higher biological effective doses at the tumor - spinal cord interface compared to single fraction treatment. 3) Dose intensification will be performed in the involved parts of the vertebrae only, while uninvolved parts are treated with conventional doses using the simultaneous integrated boost concept. It is the study hypothesis that hypo-fractionated image-guided radiosurgery significantly improves pain relief compared to historic data of conventionally fractionated radiotherapy. Primary endpoint is pain response 3 months after radiosurgery, which is defined as pain reduction of ≥ 2 points at the treated vertebral site on the 0 to 10 Visual Analogue Scale. 60 patients

  14. [Cyberknife robotic stereotactic radiotherapy: technical aspects and recent developments].

    Science.gov (United States)

    Thariat, J; Marcié, S; Marcy, P-Y; Trimaud, R; Angellier, G; Mammar, H; Bondiau, P-Y; Gerard, J-P

    2010-07-01

    Cyberknife (Accuray Inc. Sunnyvale, USA) stereotactic body radiation therapy (SBRT) involves the delivery of a small number of large doses of radiation to a target volume using continuously evolving advanced technology. It has emerged as a novel treatment modality for cancer and modified some concepts of cancer treatment. It is indicated in early-stage primary cancer, sometimes as an alternative to surgery. It is also indicated for patients with oligometastatic disease who have relatively long survival with the aim to optimize disease control with a good quality of life. Although there remain some uncertainties regarding the radiobiology of hypofractionation, local control and tolerance have been promising. Indications are increasing under strict quality assurance programs worldwide and prospective clinical evaluation.

  15. Do Carbamazepine, Gabapentin, or Other Anticonvulsants Exert Sufficient Radioprotective Effects to Alter Responses From Trigeminal Neuralgia Radiosurgery?

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    Flickinger, John C. [Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); College of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA (United States); Kim, Hyun [Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Kano, Hideyuki [Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Greenberger, Joel S.; Arai, Yoshio [Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Pittsburgh Cancer Institute, Pittsburgh, PA (United States); Niranjan, Ajay [Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Lunsford, L. Dade; Kondziolka, Douglas [Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Pittsburgh Cancer Institute, Pittsburgh, PA (United States); Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Flickinger, John C., E-mail: flickingerjc@upmc.edu [Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Pittsburgh Cancer Institute, Pittsburgh, PA (United States); Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States)

    2012-07-15

    Purpose: Laboratory studies have documented radioprotective effects with carbamazepine. We sought to determine whether carbamazepine or other anticonvulsant/neuroleptic drugs would show significant radioprotective effects in patients undergoing high-dose small-volume radiosurgery for trigeminal neuralgia. Methods and Materials: We conducted a retrospective review of 200 patients undergoing Gamma Knife (Elekta Instrument AB, Stockholm, Sweden) stereotactic radiosurgery for trigeminal neuralgia between February 1995 and May 2008. We selected patients treated with a maximum dose of 80 Gy with 4-mm diameter collimators, with no previous microvascular decompression, and follow-up {>=}6 months (median, 24 months; range, 6-153 months). At the time of radiosurgery, 28 patients were taking no anticonvulsants, 62 only carbamazepine, 35 only gabapentin, 21 carbamazepine plus gabapentin, 17 carbamazepine plus other anticonvulsants, and 9 gabapentin plus other anticonvulsants, and 28 were taking other anticonvulsants or combinations. Results: Pain improvement developed post-radiosurgery in 187 of 200 patients (93.5%). Initial complete pain relief developed in 84 of 200 patients (42%). Post-radiosurgery trigeminal neuropathy developed in 27 of 200 patients (13.5%). We could not significantly correlate pain improvement or initial complete pain relief with use of carbamazepine, gabapentin, or use of any anticonvulsants/neuroleptic drugs or other factors in univariate or multivariate analysis. Post-radiosurgery numbness/paresthesias correlated with the use of gabapentin (1 of 36 patients with gabapentin vs. 7 of 28 without, p = 0.017). In multivariate analysis, decreasing age, purely typical pain, and use of gabapentin correlated (p = 0.008, p = 0.005, and p = 0.021) with lower risks of developing post-radiosurgery trigeminal neuropathy. New post-radiosurgery numbness/paresthesias developed in 3% (1 of 36), 5% (4 of 81), and 13% (23 of 187) of patients on gabapentin alone, with age

  16. Do carbamazepine, gabapentin, or other anticonvulsants exert sufficient radioprotective effects to alter responses from trigeminal neuralgia radiosurgery?

    Science.gov (United States)

    Flickinger, John C; Kim, Hyun; Kano, Hideyuki; Greenberger, Joel S; Arai, Yoshio; Niranjan, Ajay; Lunsford, L Dade; Kondziolka, Douglas; Flickinger, John C

    2012-07-15

    Laboratory studies have documented radioprotective effects with carbamazepine. We sought to determine whether carbamazepine or other anticonvulsant/neuroleptic drugs would show significant radioprotective effects in patients undergoing high-dose small-volume radiosurgery for trigeminal neuralgia. We conducted a retrospective review of 200 patients undergoing Gamma Knife (Elekta Instrument AB, Stockholm, Sweden) stereotactic radiosurgery for trigeminal neuralgia between February 1995 and May 2008. We selected patients treated with a maximum dose of 80 Gy with 4-mm diameter collimators, with no previous microvascular decompression, and follow-up ≥6 months (median, 24 months; range, 6-153 months). At the time of radiosurgery, 28 patients were taking no anticonvulsants, 62 only carbamazepine, 35 only gabapentin, 21 carbamazepine plus gabapentin, 17 carbamazepine plus other anticonvulsants, and 9 gabapentin plus other anticonvulsants, and 28 were taking other anticonvulsants or combinations. Pain improvement developed post-radiosurgery in 187 of 200 patients (93.5%). Initial complete pain relief developed in 84 of 200 patients (42%). Post-radiosurgery trigeminal neuropathy developed in 27 of 200 patients (13.5%). We could not significantly correlate pain improvement or initial complete pain relief with use of carbamazepine, gabapentin, or use of any anticonvulsants/neuroleptic drugs or other factors in univariate or multivariate analysis. Post-radiosurgery numbness/paresthesias correlated with the use of gabapentin (1 of 36 patients with gabapentin vs. 7 of 28 without, p = 0.017). In multivariate analysis, decreasing age, purely typical pain, and use of gabapentin correlated (p = 0.008, p = 0.005, and p = 0.021) with lower risks of developing post-radiosurgery trigeminal neuropathy. New post-radiosurgery numbness/paresthesias developed in 3% (1 of 36), 5% (4 of 81), and 13% (23 of 187) of patients on gabapentin alone, with age ≤70 years, and Type 1 typical

  17. Surgery and Radiosurgery for Acromegaly: A Review of Indications, Operative Techniques, Outcomes, and Complications

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    Yvette Marquez

    2012-01-01

    Full Text Available Among multimodality treatments for acromegaly, the goals of surgical intervention are to balance maximal tumor resection while preserving normal pituitary function and maintaining patient safety. The resection of growth hormone-(GH- secreting pituitary adenomas in the hands of experienced surgeons results in hormonal remission in 50–70% of patients. Acromegalic patients often have medical comorbidities and anatomical variations complicating anesthesia and surgical management. Despite these challenges, complications such as CSF leak or new hypopituitarism following surgery remain uncommon. Over the past decade, endoscopic approaches to pituitary tumors have improved visualization and facilitated identification of additional tumor using angled telescopes. Patients with persistent acromegaly following surgery require continued medical and/or radiation-based interventions. The adjunctive use of stereotactic radiosurgery offers hormonal remission in 40–50% of patients. In this article, the current preoperative evaluation, indications for surgery, surgical approaches, role of radiosurgery, complications, and remission criteria following operative resection of GH adenomas are reviewed.

  18. Gamma Knife radiosurgery in pituitary adenomas: Why, who, and how to treat?

    Science.gov (United States)

    Castinetti, Frederic; Brue, Thierry

    2010-08-01

    Pituitary adenomas are benign tumors that can be either secreting (acromegaly, Cushing's disease, prolactinomas) or non-secreting. Transsphenoidal neurosurgery is the gold standard treatment; however, it is not always effective. Gamma Knife radiosurgery is a specific modality of stereotactic radiosurgery, a precise radiation technique. Several studies reported the efficacy and low risk of adverse effects induced by this technique: in secreting pituitary adenomas, hypersecretion is controlled in about 50% of cases and tumor volume is stabilized or decreased in 80-90% of cases, making Gamma Knife a valuable adjunctive or first-line treatment. As hormone levels decrease progressively, the main drawback is the longer time to remission (12-60 months), requiring an additional treatment during this period. Hypopituitarism is the main side effect, observed in 20-40% cases. Gamma Knife is thus useful in the therapeutic algorithms of pituitary adenomas in well-defined indications, mainly low secreting small lesions well identified on magnetic resonance imaging (MRI).

  19. Radiosurgery for the management of refractory trigeminal neuralgia

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    Ajay Niranjan

    2016-01-01

    Full Text Available Gamma Knife stereotactic radiosurgery (SRS is a minimally invasive surgical approach for managing medically refractory trigeminal neuralgia (TN. The goal of trigeminal neuralgia SRS is to eliminate or reduce the facial pain in order to improve the quality of life. Over the past 28 years, 1250 patients have undergone gamma knife SRS for TN at our institution. In our retrospective review of 503 patients who underwent SRS for management of refractory TN, 449 patients (89% experienced initial pain relief at a median latency of 1 month. At the one year mark, 73% patients were pain free (with or without medications and 80% had pain control. Repeat radiosurgery was performed for 193 patients (43%. At the one year mark, 26% of these patients were completely pain free and 78% were pain free with or without medications. The role of gamma Knife SRS in the management of medically refractory trigeminal neuralgia has evolved over the past two decades. SRS is a minimally invasive procedure and is associated with 60-90% rate of pain relief in patents with medical refractory trigeminal neuralgia. Early intervention with SRS as the initial surgica