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Fernandes J, Liao D, Dasgupta A, Tsao MN, Barnes EA. A Single-Institution Review of the Use of Radiation in the Adjuvant and Definitive Management of Keloids. Clin Oncol (R Coll Radiol) 2024; 36:e163-e167. [PMID: 38582626 DOI: 10.1016/j.clon.2024.03.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 01/31/2024] [Accepted: 03/12/2024] [Indexed: 04/08/2024]
Abstract
AIMS Many individuals suffer from keloids that are refractory to standard treatment modalities, including surgical excision alone. Radiation therapy can be used to reduce the risk of recurrent keloids post-operatively, as well as be used as primary treatment for keloids not amenable to surgical resection. The purpose of this study was to review our institutional experience of radiation therapy for keloid management. MATERIALS AND METHODS A retrospective review of patients treated with radiation therapy for keloids between 2014 and 2020 at our institution was performed. RESULTS A total of 70 keloids in 41 patients were treated. For the 55 keloids treated with post-operative radiation therapy (16Gy delivered in 2 fractions), 82.5% (33/40) of evaluable lesions did not recur. Among the 15 keloids treated with definitive radiation therapy (24Gy delivered in 3 fractions), 78.6% (11/14) of evaluable keloids showed complete flattening, and 14.3% (2/14) had partial flattening. Both acute and late toxicities were mild, with only a single instance of grade 3 toxicity (dermatitis). CONCLUSION Our study confirms that radiation therapy has a role in reducing the risk of keloid recurrence post-operatively, and plays an important role in the definitive management of unresectable keloids.
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Affiliation(s)
- J Fernandes
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Hospital, University of Toronto, Toronto, Ontario, Canada
| | - D Liao
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Hospital, University of Toronto, Toronto, Ontario, Canada
| | - A Dasgupta
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Hospital, University of Toronto, Toronto, Ontario, Canada
| | - M N Tsao
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Hospital, University of Toronto, Toronto, Ontario, Canada
| | - E A Barnes
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Hospital, University of Toronto, Toronto, Ontario, Canada.
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Mushonga M, Ung Y, Louie AV, Cheung P, Poon I, Zhang L, Tsao MN. Unanticipated Radiation Replanning for Stage III Non-small Cell Lung Cancer. Adv Radiat Oncol 2023; 8:101275. [PMID: 38047222 PMCID: PMC10692281 DOI: 10.1016/j.adro.2023.101275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 05/10/2023] [Indexed: 12/05/2023] Open
Abstract
Purpose The purpose of this study was to identify factors associated with unanticipated radiation therapy (RT) replanning in stage III non-small cell lung cancer (NSCLC). Methods and Materials Patients from a single institution with newly diagnosed stage III NSCLC treated with radical RT from January 1, 2016, to December 31, 2019, were retrospectively analyzed. The frequency and reasons for replanning were determined. Logistic regression analysis was used to identify factors associated with replanning. Results Of 144 patients included in this study, 11% (n = 16) required replanning after the start of RT. The reason for replanning in these 16 patients was changes in the target detected by cone beam computed tomography (shift in 10 patients, shrinkage in 5 patients, and growth in 1 patient). Larger planning target volume (primary and nodal) was statistically predictive of replanning (odds ratio, 2.5; 95% CI, 1.2-5.4; P = .02). The actuarial median overall survival was 33.3 months (95% CI, 10.3-43.9) for the 16 patients who were replanned and 36.3 months (95% CI, 27.4-66.5) for the remaining 128 patients (P = .96). The median time to local recurrence was 25.0 months (95% CI, 10.3-41.3) for those patients who underwent replanning, which was similar to those patients who did not undergo replanning (19.5 months; 95% CI, 11.8-23.2; P = .28). Conclusions In this study, 11% of patients treated with radical RT for NSCLC required replanning due to changes in the target detected by cone beam computed tomography. A larger planning target volume predicts a higher likelihood of requiring adaptive RT. Overall survival and local control were similar between patients who were replanned compared with those who were not replanned.
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Affiliation(s)
- Melinda Mushonga
- Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Yee Ung
- Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Alexander V. Louie
- Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Patrick Cheung
- Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Ian Poon
- Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | | | - May N. Tsao
- Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
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Beriwal S, Corrigan KL, McDermott PN, Ryckman J, Tsao MN, Zheng D, Joiner MC, Dominello MM, Burmeister J. Three Discipline Collaborative Radiation Therapy (3DCRT) special debate: Radiation oncology has become so technologically complex that basic fundamental physics should no longer be included in the modern curriculum for radiation oncology residents. J Appl Clin Med Phys 2023; 24:e14128. [PMID: 37606366 PMCID: PMC10476972 DOI: 10.1002/acm2.14128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 08/02/2023] [Indexed: 08/23/2023] Open
Affiliation(s)
- Sushil Beriwal
- Department of Radiation OncologyAllegheny Health NetworkWexfordPennsylvaniaUSA
| | - Kelsey L. Corrigan
- Department of Radiation OncologyMD Anderson Cancer CenterHoustonTexasUSA
| | | | - Jeffrey Ryckman
- Camden Clark Comprehensive Regional Cancer CenterWest Virginia Cancer InstituteParkersburgWest VirginiaUSA
| | - May N. Tsao
- Department of Radiation OncologyUniversity of Toronto, Odette Cancer CentreToronto, ONCanada
| | - Dandan Zheng
- Department of Radiation OncologyUniversity of RochesterRochesterNew YorkUSA
| | - Michael C. Joiner
- Department of OncologyWayne State University School of MedicineDetroitMichiganUSA
| | - Michael M. Dominello
- Department of OncologyWayne State University School of MedicineDetroitMichiganUSA
| | - Jay Burmeister
- Department of OncologyWayne State University School of MedicineDetroitMichiganUSA
- Gershenson Radiation Oncology CenterBarbara Ann Karmanos Cancer InstituteDetroitMichiganUSA
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Barnes EA, Tsao MN, Taggar AS, Ravi A, Paudel MR. Optimizing surface mould brachytherapy for treatment of nasal basal cell carcinoma using customized applicators. Brachytherapy 2023; 22:665-672. [PMID: 37277286 DOI: 10.1016/j.brachy.2023.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 03/23/2023] [Accepted: 05/04/2023] [Indexed: 06/07/2023]
Abstract
PURPOSE Surface mould brachytherapy (SMBT) is ideal in treating superficial skin cancer over the curved surface of the nasal ala. We describe the process of initiating and optimizing SMBT treatment at our institution including clinical workflow, generation of three dimensional (3D) printed custom applicators, and clinical outcomes. METHODS AND MATERIALS Planning CT scans were used to acquire images for delineating target volumes. The applicator was designed with customized catheter positioning (3-5mm from target) to cover target volume while sparing dose to organs at risk (OAR) such as adjacent skin and nasal mucosa. Applicators were 3D printed, with transparent resin to aid visualization of underlying skin. Dosimetric parameters evaluated included CTV D90, CTV D0.1cc, and D2cc to OARs. Clinical outcomes assessed were local control, acute and late toxicity (Common Terminology Criteria for Adverse Events v5.0 [CTCAEv5.0]), and cosmesis (Radiation Therapy Oncology Group [RTOG]). RESULTS Ten patients were treated with SMBT with a median followup of 17.8 months. Dose prescription was 40 Gy in 10 daily fractions. Mean CTV D90 was 38.5 Gy (range 34.7-40.6), mean CTV D0.1cc 49.2 Gy (range 45.6-53.5), which was <140% of the prescription dose in all patients. Treatment was well tolerated, with acceptable Grade 2 acute, Grade 0-1 late skin toxicity, and good-excellent cosmesis for all patients. Two patients experienced local failure, and both underwent surgical salvage. CONCLUSIONS SMBT was successfully planned and delivered for superficial nasal BCC using 3D printed custom applicators. Excellent target coverage was achieved while minimizing dose to OAR. Toxicity and cosmesis rates were good-excellent.
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Affiliation(s)
- Elizabeth A Barnes
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada.
| | - May N Tsao
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Amandeep S Taggar
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Ananth Ravi
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Moti R Paudel
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada; Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
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Ali S, Louie AV, Tsao MN. Severe kyphosis and stereotactic lung radiation therapy set-up: A case report and lessons learned. J Med Imaging Radiat Sci 2023; 54:566-571. [PMID: 37422412 DOI: 10.1016/j.jmir.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/20/2023] [Accepted: 06/26/2023] [Indexed: 07/10/2023]
Abstract
INTRODUCTION Stereotactic body radiation therapy (SBRT) for lung cancers allows for safe ablative radiation doses to be delivered precisely to treat localized stage 1 lung cancers and for the treatment of lung oligometastasis/es. The successful delivery of lung SBRT requires multidisciplinary technical expertise, from radiation oncologists, medical physicists, radiation therapists, and a clinical specialist radiation therapist in SBRT. While the majority of SBRT lung set-ups are routine, we present a challenging situation in the lung SBRT set-up for a patient with severe kyphosis. CASE AND OUTCOMES An 80-year-old woman was diagnosed with a right upper lobe non-small cell lung cancer. She declined surgery and was referred for lung SBRT. Her severe kyphosis did present challenges in terms of reproducible lung SBRT set-up. We were successful in immobilizing this patient in a vacuum customized rigid support which was shaped to accommodate this patient's extreme kyphosis and elevated head. The patient tolerated the treatment position and successfully completed her lung SBRT treatments comfortably, without any reproducibility issues. Four months after SBRT, the patient was doing well without any new chest symptoms. DISCUSSION This report is the first, in the published medical literature, to describe a lung SBRT set-up for a patient with extreme kyphosis. Her successful set-up and ability to complete her lung SBRT was dependent on creative problem-solving from the multi-disciplinary team and a patient-centred approach to care CONCLUSION: Multidisciplinary collaboration was essential in the successful SBRT treatment for a severely kyphotic patient. The use of a vacuum customized thoracic rigid support was effectively used in a patient with severe kyphosis for lung SBRT. Results from this case report could be useful and guide other clinicians if presented with similarly challenging cases.
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Affiliation(s)
- S Ali
- Odette Cancer Centre, Sunnybrook Health Sciences, Toronto, ON, CANADA
| | - A V Louie
- Odette Cancer Centre, Sunnybrook Health Sciences, Toronto, ON, CANADA; Department of Radiation Oncology, University of Toronto, Toronto, ON, CANADA
| | - M N Tsao
- Odette Cancer Centre, Sunnybrook Health Sciences, Toronto, ON, CANADA; Department of Radiation Oncology, University of Toronto, Toronto, ON, CANADA.
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Babic S, McNiven AL, Bezjak A, Balogh JM, Mah K, Tsao MN. Evolution and Evaluation of a Structured Applied Physics Course for Radiation Oncology and Radiation Physics Trainees. J Cancer Educ 2023; 38:813-820. [PMID: 35761143 PMCID: PMC9243863 DOI: 10.1007/s13187-022-02190-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 06/05/2022] [Indexed: 06/02/2023]
Abstract
We sought to supplement medical physics textbook knowledge and clinical learning with case-based discussions. To our knowledge, this is the first report on a structured combined applied physics curriculum for radiation oncology (RO) and medical physics (MP) trainees. We reviewed our yearly applied physics course given from the years 2016-2021 inclusive. The number of applied physics trainees ranged from 7 to 14 per year (2-9 RO and 3-6 MP residents per year). Each session was taught by a pair of (RO and MP) faculty members. Twenty-nine case-based sessions were given yearly (2016 to 2019). Because of the COVID-19 pandemic restrictions, the course was shortened to 8 case-based sessions in 2020 and 2021. For the years 2016-2021, the mean and median teaching evaluation scores were 4.65 and 5, respectively (range 2-5), where 1 represents worse teaching quality and 5, the best teaching quality. For the year 2021, 2 questions relating to the video virtual format (implemented due to the covid-19 pandemic), revealed consistent high scores with the mean and median responses of 4.14 and 5, respectively (range 1-5). The results from the teaching evaluation scores indicate that the trainees highly valued the teaching sessions and teachers. Our experience indicates that a case-based applied physics course was delivered successfully with continued high teaching evaluation scores. A video virtual platform for an applied physics course could be useful, especially for small programs without a structured applied physics curriculum.
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Affiliation(s)
- S Babic
- Department of Radiation Oncology, University of Toronto, Carlo Fidani Regional Cancer Centre - Trillium Health Partners (Credit Valley Site), Mississauga, ON, Canada
| | - A L McNiven
- Department of Radiation Oncology, University of Toronto, Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - A Bezjak
- Department of Radiation Oncology, University of Toronto, Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - J M Balogh
- Department of Radiation Oncology, Odette Cancer Centre - Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Ave, Toronto, ON, Canada
| | - K Mah
- Department of Radiation Oncology, University of Toronto, Princess Margaret Cancer Centre, Toronto, ON, Canada
- Department of Radiation Oncology, Odette Cancer Centre - Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Ave, Toronto, ON, Canada
| | - M N Tsao
- Department of Radiation Oncology, Odette Cancer Centre - Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Ave, Toronto, ON, Canada.
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Tsao MN, Babic S, McNiven A, Bezjak A, Balogh J, Mah K. 181: A Review of a Structured Applied Physics Course for Radiation Oncology and Radiation Physics Trainees. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)04461-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Tsao MN, Louie AV. Radical Radiation for Large-Volume Locally Advanced Non-Small Cell Lung Cancer: Constrained by Constraints! Int J Radiat Oncol Biol Phys 2021; 110:261-263. [PMID: 33989567 DOI: 10.1016/j.ijrobp.2020.09.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 09/09/2020] [Indexed: 11/30/2022]
Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
| | - Alexander V Louie
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
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Abstract
BACKGROUND This is an updated version of the original Cochrane Review published in Issue 8, 2016. High grade glioma (HGG) is a rapidly growing brain tumour in the supporting cells of the nervous system, with several subtypes such as glioblastoma (grade IV astrocytoma), anaplastic (grade III) astrocytoma and anaplastic (grade III) oligodendroglioma. Studies have investigated the best strategy to give radiation to people with HGG. Conventional fractionated radiotherapy involves giving a daily radiation dose (called a fraction) of 180 cGy to 200 cGy. Hypofractionated radiotherapy uses higher daily doses, which reduces the overall number of fractions and treatment time. Hyperfractionated radiotherapy which uses a lower daily dose with a greater number of fractions and multiple fractions per day to deliver a total dose at least equivalent to external beam daily conventionally fractionated radiotherapy in the same time frame. The aim is to reduce the potential for late toxicity. Accelerated radiotherapy (dose escalation) refers to the delivery of multiple fractions per day using daily doses of radiation consistent with external beam daily conventionally fractionated radiotherapy doses. The aim is to reduce the overall treatment time; typically, two or three fractions per day may be delivered with a six to eight hour gap between fractions. OBJECTIVES To assess the effects of postoperative external beam radiation dose escalation in adults with HGG. SEARCH METHODS We searched CENTRAL, MEDLINE Ovid and Embase Ovid to August 2019 for relevant randomised phase III trials. SELECTION CRITERIA We included adults with a pathological diagnosis of HGG randomised to the following external beam radiation regimens: daily conventionally fractionated radiotherapy versus no radiotherapy; hypofractionated radiotherapy versus daily conventionally fractionated radiotherapy; hyperfractionated radiotherapy versus daily conventionally fractionated radiotherapy or accelerated radiotherapy versus daily conventionally fractionated radiotherapy. DATA COLLECTION AND ANALYSIS The primary outcomes were overall survival and adverse effects. The secondary outcomes were progression free survival and quality of life. We used the standard methodological procedures expected by Cochrane. We assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS Since the last version of this review, we identified no new relevant trials for inclusion. We included 11 randomised controlled trials (RCTs) with 2062 participants and 1537 in the relevant arms for this review. There was an overall survival benefit for people with HGG receiving postoperative radiotherapy compared to the participants receiving postoperative supportive care. For the four pooled RCTs (397 participants), the overall hazard ratio (HR) for survival was 2.01 favouring postoperative radiotherapy (95% confidence interval (CI) 1.58 to 2.55; P < 0.00001; moderate-certainty evidence). Although these trials may not have completely reported adverse effects, they did not note any significant toxicity attributable to radiation. Progression free survival and quality of life could not be pooled due to lack of data. Overall survival was similar between hypofractionated and conventional radiotherapy in five trials (943 participants), where the HR was 0.95 (95% CI 0.78 to 1.17; P = 0.63; very low-certainty evidence. The trials reported that hypofractionated and conventional radiotherapy were well tolerated with mild acute adverse effects. These trials only reported one participant in the hypofractionated arm developing symptomatic radiation necrosis that required surgery. Progression free survival and quality of life could not be pooled due to the lack of data. Overall survival was similar between hypofractionated and conventional radiotherapy in the subset of two trials (293 participants) which included participants aged 60 years and older with glioblastoma. For this category, the HR was 1.16 (95% CI 0.92 to 1.46; P = 0.21; high-certainty evidence). There were two trials which compared hyperfractionated radiotherapy versus conventional radiation and one trial which compared accelerated radiotherapy versus conventional radiation. However, the results could not be pooled. The conventionally fractionated radiotherapy regimens were 4500 cGy to 6000 cGy given in 180 cGy to 200 cGy daily fractions, over five to six weeks. All trials generally included participants with World Health Organization (WHO) performance status from 0 to 2 and Karnofsky performance status of 50 and higher. The risk of selection bias was generally low among these RCTs. The number of participants lost to follow-up for the outcome of overall survival was low. Attrition, performance, detection and reporting bias for the outcome of overall survival was low. There was unclear attrition, performance, detection and reporting bias relating to the outcomes of adverse effects, progression free survival and quality of life. AUTHORS' CONCLUSIONS Postoperative conventional daily radiotherapy probably improves survival for adults with good performance status and HGG compared to no postoperative radiotherapy. Hypofractionated radiotherapy has similar efficacy for survival compared to conventional radiotherapy, particularly for individuals aged 60 years and older with glioblastoma. There are insufficient data regarding hyperfractionation versus conventionally fractionated radiation (without chemotherapy) and for accelerated radiation versus conventionally fractionated radiation (without chemotherapy). There are HGG subsets who have poor prognosis even with treatment (e.g. glioblastoma histology, older age and poor performance status). These HGG individuals with poor prognosis have generally been excluded from randomised trials based on poor performance status. No randomised trial has compared comfort measures or best supportive care with an active intervention using radiotherapy or chemotherapy in these people with poor prognosis. Since the last version of this review, we found no new relevant studies. The search identified three new trials, but all were excluded as none had a conventionally fractionated radiotherapy arm.
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Affiliation(s)
- Luluel Khan
- Department of Radiation Oncology, University of Toronto, Toronto, Canada
| | - Hany Soliman
- Department of Radiation Oncology, University of Toronto, Toronto, Canada
| | - Arjun Sahgal
- Department of Radiation Oncology, University of Toronto, Toronto, Canada
| | - James Perry
- Crolla Endowed Chair of Neuro-Oncology Research, Sunnybrook Health Sciences Centre and Odette Cancer Centre, Toronto, Canada
| | - Wei Xu
- Department of Biostatistics, University of Toronto, Toronto, Canada
| | - May N Tsao
- Department of Radiation Oncology, University of Toronto, Toronto, Canada
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Tsao MN, Ven LI', Cheung P, Poon I, Ung Y, Louie AV. Stereotactic Body Radiation Therapy for Extracranial Oligometastatic Non-small-cell Lung Cancer: A Systematic Review. Clin Lung Cancer 2019; 21:95-105.e1. [PMID: 31959533 DOI: 10.1016/j.cllc.2019.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Revised: 10/26/2019] [Accepted: 11/12/2019] [Indexed: 12/13/2022]
Abstract
Stereotactic body radiation therapy (SBRT) has emerged as a treatment modality for selected patients with oligometastatic non-small-cell lung cancer (NSCLC). The objectives of this systematic review were to explore the benefits and risks of SBRT for extracranial oligometastatic NSCLC. The MEDLINE, Embase, PubMed, and CENTRAL databases were searched for relevant articles from January 1, 2000 to July 23, 2019. Fully published phase III or phase II trials of any sample size were included. Retrospective series published in manuscript form with at least 50 patients were also included. Four prospective phase II randomized trials (total, 188 participants), 4 prospective non-randomized studies (total, 140 participants), and eleven retrospective studies (total, 1288 participants) were included in this systematic review. A variety of dose fractionation schemes were used. The median overall survival (OS) ranged from 13.5 to 55 months. Progression-free survival (PFS) ranged from 4.4 to 14.7 months. Quality of life outcomes were reported in 2 studies. None of the studies reported symptom control outcomes. There are no fully completed phase III randomized trials that clarify the risks and benefits of SBRT for oligometastatic NSCLC. Higher PFS and OS with SBRT were reported in 4 phase II randomized studies. The results from mature phase III randomized data regarding whether SBRT for oligometastatic NSCLC benefits patients in terms of OS, PFS, quality of life, and symptom control are needed.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
| | - Lieke In 't Ven
- Department of Radiation Oncology, School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Patrick Cheung
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Ian Poon
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Yee Ung
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Alexander V Louie
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
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Tsao MN, Barnes EA, Chow E. Multiple bone metastases: what the palliative care specialist should know about the potential, limitations and practical aspects of radiation therapy. Ann Palliat Med 2019; 9:1307-1313. [PMID: 31431026 DOI: 10.21037/apm.2019.07.09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 06/13/2019] [Indexed: 11/06/2022]
Abstract
Bone metastases represent a significant health care problem in the cancer population. The most common symptom for bone metastases is pain. Bone metastases may also cause pathologic fracture, spinal cord compression, cauda equina compression and serum calcium disorders. This review article summarizes the epidemiology, diagnostic modalities, role for radiation, and future directions as it pertains to bone metastases. Radiotherapy is an effective and standard modality for the treatment of painful complicated and uncomplicated bony metastases. Further strategies are needed to optimize pain relief, quality of life and survival in the bone metastases cancer population.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
| | - Elizabeth A Barnes
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Edward Chow
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
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Barnes EA, Sinclair E, Assaad D, Fialkov J, Antonyshyn O, Tsao MN. Radiation for below the knee skin cancers: a single institution experience. J DERMATOL TREAT 2019; 31:563-566. [PMID: 31294616 DOI: 10.1080/09546634.2019.1641582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Background: Historically, radiation to skin cancers for the lower legs has been avoided due to the perceived increased risk of radiation toxicity (poor wound healing, radiation necrosis). However, there is a paucity of published data regarding this perceived risk.Purpose: The objective was to review the risk of poor wound healing/radiation necrosis occurring post radiation and to determine rates of complete response (CR), partial response (PR), and progressive disease after radiation therapyMaterials and methods: A retrospective review of patients treated with radiation for skin cancer below the knee was undertaken from January 1, 2013 to May 31, 2018.Results: A total of 25 patients with 39 below the knee skin sites were treated with radiation. Mean follow-up time was 19 months (range 3 months-7.2 years). Crude CR, PR and progression rates for the treated lesions were 65%, 19%, and 16% respectively. Four out of 23 (17%) patients developed Grade 3 skin toxicity. There were no grades 4 or 5 toxicities.Conclusions: For patients not eligible for surgery, radiation therapy is an option with a moderate chance of complete response (65%) and a 17% risk of poor wound healing/radiation necrosis.
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Affiliation(s)
- Elizabeth A Barnes
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Emily Sinclair
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Dalal Assaad
- Department of Dermatology and Pathology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Jeffrey Fialkov
- Division of Plastic and Reconstructive Surgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Oleh Antonyshyn
- Division of Plastic and Reconstructive Surgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - May N Tsao
- Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
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Niglas M, Raman S, Rodin D, Detsky J, DeAngelis C, Soliman H, Chow E, Tsao MN. Should dexamethasone be standard in the prophylaxis of pain flare after palliative radiotherapy for bone metastases?—a debate. Ann Palliat Med 2018; 7:279-283. [DOI: 10.21037/apm.2017.04.08] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/28/2017] [Indexed: 11/06/2022]
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Tsao MN, Xu W, Wong RKS, Lloyd N, Laperriere N, Sahgal A, Rakovitch E, Chow E. Whole brain radiotherapy for the treatment of newly diagnosed multiple brain metastases. Cochrane Database Syst Rev 2018; 1:CD003869. [PMID: 29365347 PMCID: PMC6491334 DOI: 10.1002/14651858.cd003869.pub4] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND This is an update to the review published in the Cochrane Library (2012, Issue 4).It is estimated that 20% to 40% of people with cancer will develop brain metastases during the course of their illness. The burden of brain metastases impacts quality and length of survival. OBJECTIVES To assess the effectiveness and adverse effects of whole brain radiotherapy (WBRT) given alone or in combination with other therapies to adults with newly diagnosed multiple brain metastases. SEARCH METHODS We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase to May 2017 and the National Cancer Institute Physicians Data Query for ongoing trials. SELECTION CRITERIA We included phase III randomised controlled trials (RCTs) comparing WBRT versus other treatments for adults with newly diagnosed multiple brain metastases. DATA COLLECTION AND ANALYSIS Two review authors independently assessed trial quality and abstracted information in accordance with Cochrane methods. MAIN RESULTS We added 10 RCTs to this updated review. The review now includes 54 published trials (45 fully published reports, four abstracts, and five subsets of data from previously published RCTs) involving 11,898 participants.Lower biological WBRT doses versus controlThe hazard ratio (HR) for overall survival (OS) with lower biological WBRT doses as compared with control (3000 cGy in 10 daily fractions) was 1.21 (95% confidence interval (CI) 1.04 to 1.40; P = 0.01; moderate-certainty evidence) in favour of control. The HR for neurological function improvement (NFI) was 1.74 (95% CI 1.06 to 2.84; P = 0.03; moderate-certainty evidence) in favour of control fractionation.Higher biological WBRT doses versus controlThe HR for OS with higher biological WBRT doses as compared with control (3000 cGy in 10 daily fractions) was 0.97 (95% CI 0.83 to 1.12; P = 0.65; moderate-certainty evidence). The HR for NFI was 1.14 (95% CI 0.92 to 1.42; P = 0.23; moderate-certainty evidence).WBRT and radiosensitisersThe addition of radiosensitisers to WBRT did not confer additional benefit for OS (HR 1.05, 95% CI 0.99 to 1.12; P = 0.12; moderate-certainty evidence) or for brain tumour response rates (odds ratio (OR) 0.84, 95% CI 0.63 to 1.11; P = 0.22; high-certainty evidence).Radiosurgery and WBRT versus WBRT aloneThe HR for OS with use of WBRT and radiosurgery boost as compared with WBRT alone for selected participants was 0.61 (95% CI 0.27 to 1.39; P = 0.24; moderate-certainty evidence). For overall brain control at one year, the HR was 0.39 (95% CI 0.25 to 0.60; P < 0.0001; high-certainty evidence) favouring the WBRT and radiosurgery boost group.Radiosurgery alone versus radiosurgery and WBRTThe HR for local brain control was 2.73 (95% CI 1.87 to 3.99; P < 0.00001; high-certainty evidence)favouring the addition of WBRT to radiosurgery. The HR for distant brain control was 2.34 (95% CI 1.73 to 3.18; P < 0.00001; high-certainty evidence) favouring WBRT and radiosurgery. The HR for OS was 1.00 (95% CI 0.80 to 1.25; P = 0.99; moderate-certainty evidence). Two trials reported worse neurocognitive outcomes and one trial reported worse quality of life outcomes when WBRT was added to radiosurgery.We could not pool data from trials related to chemotherapy, optimal supportive care (OSC), molecular targeted agents, neurocognitive protective agents, and hippocampal sparing WBRT. However, one trial reported no differences in quality-adjusted life-years for selected participants with brain metastases from non-small-cell lung cancer randomised to OSC and WBRT versus OSC alone. AUTHORS' CONCLUSIONS None of the trials with altered higher biological WBRT dose-fractionation schemes reported benefit for OS, NFI, or symptom control compared with standard care. However, OS and NFI were worse for lower biological WBRT dose-fractionation schemes than for standard dose schedules.The addition of WBRT to radiosurgery improved local and distant brain control in selected people with brain metastases, but data show worse neurocognitive outcomes and no differences in OS.Selected people with multiple brain metastases from non-small-cell lung cancer may show no difference in OS when OSC is given and WBRT is omitted.Use of radiosensitisers, chemotherapy, or molecular targeted agents in conjunction with WBRT remains experimental.Further trials are needed to evaluate the use of neurocognitive protective agents and hippocampal sparing with WBRT. As well, future trials should examine homogeneous participants with brain metastases with focus on prognostic features and molecular markers.
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Affiliation(s)
- May N Tsao
- University of TorontoDepartment of Radiation Oncology2075 Bayview AvenueTorontoOntarioCanadaM4N 3M5
| | - Wei Xu
- University of TorontoDepartment of BiostatisticsUniversity Health NetworkTorontoOntarioCanada
| | - Rebecca KS Wong
- Princess Margaret Cancer CentreDepartment of Radiation Oncology5th Floor, 610 University AvenueTorontoONCanadaM5G 2M9
| | - Nancy Lloyd
- McMaster UniversityDepartment of Clinical Epidemiology and Biostatistics1280 Main Street WestCourthouse T‐27, 3rd FloorHamiltonOntarioCanadaL8S 4L8
| | - Normand Laperriere
- Princess Margaret Cancer CentreDepartment of Radiation Oncology5th Floor, 610 University AvenueTorontoONCanadaM5G 2M9
| | - Arjun Sahgal
- Odette Cancer CentreDepartment of Radiation OncologySunnybrook Health Sciences Centre2075 Bayview Avenue, T‐WingTorontoCanadaM4N 3M5
| | - Eileen Rakovitch
- Odette Cancer CentreDepartment of Radiation OncologySunnybrook Health Sciences Centre2075 Bayview Avenue, T‐WingTorontoCanadaM4N 3M5
| | - Edward Chow
- Odette Cancer CentreDepartment of Radiation OncologySunnybrook Health Sciences Centre2075 Bayview Avenue, T‐WingTorontoCanadaM4N 3M5
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Moroney C, Perry JR, Tsang DS, Bilodeau D, Mueller C, Soliman H, Myrehaug S, Sahgal A, Tseng CL, Tsao MN. Hospitalizations in elderly glioblastoma patients. Ann Palliat Med 2017; 6:S161-S169. [PMID: 28866896 DOI: 10.21037/apm.2017.06.02] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 05/28/2017] [Indexed: 11/06/2022]
Abstract
BACKGROUND Elderly glioblastoma (GB) patients are at risk of hospitalizations due to the morbidity of the disease and possible treatment toxicity. METHODS In this observational cohort study, 255 newly diagnosed GB patients age 65 years and older were included. Survival, emergency room visits and admissions to an acute care hospital were determined. Mean and median total health care costs were calculated. Risk factors for Emergency room visits and acute care hospital admissions were determined. RESULTS Median overall survival was 6 months. The majority of patients (68%) had at least one visit to the emergency department and 77% had at least one admission to acute care. The mean and median total costs (hospital, ambulatory, physician billing, other health care costs) per patient were $162,479.78 (CAN) and $125,511.00 (CAN), respectively. Treatment with radiation or treatment with radio-chemotherapy was associated with a relative risk (RR) of 2.31 (95% CI: 1.44-3.7; P=0.0005) and 2.19 (95% CI: 1.28-3.74; P=0.004), respectively for emergency department visits as compared to patients who were managed with comfort measures only. Patients with a baseline ECOG 0 had a RR of 1.71 (95% CI: 1.06-2.77; P=0.0289) and patients with baseline ECOG 1 had a RR of 1.49 (0.98-2.26; P=0.0623) for hospital admission as compared to patients with ECOG 4. CONCLUSIONS A large proportion of elderly GB patients (particularly those with good baseline performance status who underwent active treatment) presented to the emergency department and had at least one admission to acute care.
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Affiliation(s)
- Claire Moroney
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - James R Perry
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Derek S Tsang
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Denise Bilodeau
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Chris Mueller
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Hany Soliman
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Sten Myrehaug
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Arjun Sahgal
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - Chia-Lin Tseng
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
| | - May N Tsao
- Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
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Tsao MN, Sahgal A, Xu W, De Salles A, Hayashi M, Levivier M, Ma L, Martinez R, Régis J, Ryu S, Slotman BJ, Paddick I. Stereotactic radiosurgery for vestibular schwannoma: International Stereotactic Radiosurgery Society (ISRS) Practice Guideline. J Radiosurg SBRT 2017; 5:5-24. [PMID: 29296459 PMCID: PMC5675503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 02/02/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVES The aim of this systematic review was to develop International Stereotactic Radiosurgery Society (ISRS) consensus guideline statements for vestibular schwannoma. METHODS A systematic review of the literature was performed up to April 2015. RESULTS A total of 55 full-text articles were included in the analysis. All studies were retrospective, except for 2 prospective quality of life studies. Five-year tumour control rates with Gamma Knife radiosurgery (RS), single fraction linac RS, or fractionated (either hypofractionated or conventional fractionation) stereotactic radiation therapy (FSRT) were similar at 81-100%. The single fraction RS series (linac or Gamma Knife) with tumour marginal doses between 12 and 14 Gy revealed 5-year tumour control rates of 90-99%, hearing preservation rates of 41-79%, facial nerve preservation rates of 95-100% and trigeminal preservation rates of 79-99%.There were 6 non-randomized studies comparing single fraction RS versus FSRT. There was no statistically significant difference in tumour control; HR=1.66 (95% CI 0.81, 3.42), p =0.17, facial nerve function; HR = 0.67 (95% CI 0.30, 1.49), p =0.33, trigeminal nerve function; HR = 0.80 (95% CI 0.41, 1.56), p =0.51, and hearing preservation; HR = 1.10 (95% CI 0.72, 1.68), p =0.65 comparing single fraction RS with FSRT.Nine quality of life reports yielded conflicting results as to which modality (surgery, observation, or radiation) was associated with better quality of life outcomes. CONCLUSIONS There are no randomized trials to help guide management of patients with vestibular schwannoma. Within the limitations of the retrospective series, a number of consensus statements were made.
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Affiliation(s)
- May N. Tsao
- Department of Radiation Oncology, University of Toronto, Odette Cancer Centre, Toronto, ON, Canada, M4N 3M5
| | - Arjun Sahgal
- Department of Radiation Oncology, University of Toronto, Odette Cancer Centre, Toronto, ON, Canada, M4N 3M5
| | - Wei Xu
- Department of Biostatistics, University of Toronto, ON, Canada, M5G 2M9
| | - Antonio De Salles
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, CA 90005, USA and HCor Neuroscience, Sao Paulo, SP, Brazil, 04004-030
| | - Motohiro Hayashi
- Department of Neurosurgery, Tokyo Women’s Medical University, Toyko, Japan, 162-8666
| | - Marc Levivier
- Neurosurgery Service and Gamma Knife Center, Centre Hospitalier Universitaire Vaudois, CH-1011 Lausanne, Switzerland
| | - Lijun Ma
- Division Physics, Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94143, USA
| | - Roberto Martinez
- Department Neurosurgery, Ruber Internacional Hospital, E-28034 Madrid, Spain
| | - Jean Régis
- Department of Functional Neurosurgery, Timone University Hospital, Aix-Marseille University, F-13385 Marseille, France
| | - Sam Ryu
- Department of Radiation Oncology and Neurosurgery, Stony Brook University, Stony Brook, NY 11794, USA
| | - Ben J. Slotman
- Department of Radiation Oncology, VU University Medical Center, NL-1007 Amsterdam, Netherlands
| | - Ian Paddick
- National Hospital for Neurology and Neurosurgery, London, WC1N 3BG, UK
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Tsao MN. Should optimal supportive care alone be the standard of care for brain metastases patients from non-small cell lung cancer, who are not eligible for radiosurgery or surgery? Transl Cancer Res 2016. [DOI: 10.21037/tcr.2016.12.03] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Tsao MN, Sinclair E, Assaad D, Fialkov J, Antonyshyn O, Barnes E. Radiation therapy for the treatment of skin Kaposi sarcoma. Ann Palliat Med 2016; 5:298-302. [DOI: 10.21037/apm.2016.08.03] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 06/15/2016] [Indexed: 11/06/2022]
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Abstract
BACKGROUND The morbidity and mortality associated with metastatic disease to brain make this problem a formidable challenge faced by health care providers and caregivers. The aim of this review is to summarize management for patients with brain metastases with a particular focus on symptom management. METHODS A systematic review of the literature was performed. Outcomes of interest included survival, brain control (local in field and whole brain). In particular, symptom control (quality of life, neurological function and neurocognition) was examined. RESULTS Steroids provide relief of symptoms due to intra-cerebral edema. The steroid of choice is dexamethasone. Anti-seizure medications should not be given as prophylaxis but instead be given for treatment of seizures. Depending on patient, tumour and treatment factors, management for brain metastases range from optimal supportive care including the use of steroids, whole brain radiotherapy (WBRT), radiosurgery, surgery alone or in combination. Surgery or radiosurgery improves survival for selected patients with single brain metastasis as compared to WBRT alone. Ongoing research topics include focal postoperative cavity radiation, focal fractionated regimens, molecular targeted therapies, chemoprevention of brain metastases and neurocognitive protection (such as neuro-protective drugs and radiation techniques such as hippocampal sparing). CONCLUSIONS The management of brain metastases has evolved over the decades. Other than survival and brain control (local in-field and whole brain), the outcomes of quality of life and neurocognition are becoming increasingly important.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, University of Toronto, Odette Cancer Centre, 2075 Bayview Ave., Toronto, ON, Canada.
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Abstract
BACKGROUND The incidence of high grade glioma (HGG) is approximately 5 per 100,000 person-years in Europe and North America. OBJECTIVES To assess the effects of postoperative external beam radiation dose escalation in adults with HGG. SEARCH METHODS We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 9), MEDLINE (1977 to October 2015) and Embase (1980 to end October 2015) for relevant randomised phase III trials. SELECTION CRITERIA We included adults with a pathological diagnosis of HGG randomised to the following external beam radiation regimens.1. Daily conventionally fractionated radiation therapy versus no radiation therapy.2. Hypofractionated radiation therapy versus daily conventionally fractionated radiation therapy.3. Hyperfractionated radiation therapy versus daily conventionally fractionated radiation therapy.4. Accelerated radiation therapy versus daily conventionally fractionated radiation therapy. DATA COLLECTION AND ANALYSIS The primary outcomes were overall survival and adverse effects. The secondary outcomes were progression-free survival and quality of life. We used the standard methodological procedures expected by Cochrane. We used the GRADE approach, as outlined by Cochrane, to interpret the overall quality of the evidence from included studies. MAIN RESULTS We included 11 randomised controlled trials (RCTs) with a total of 2062 participants and 1537 in the relevant arms for this review. There was an overall survival benefit for HGG participants receiving postoperative radiotherapy compared to the participants receiving postoperative supportive care. For the four pooled RCTs (397 participants), the overall hazard ratio (HR) for survival was 2.01 (95% confidence interval (CI) 1.58 to 2.55, P < 0.00001), moderate GRADE quality evidence favouring postoperative radiotherapy. Although these trials may not have completely reported adverse effects, they did not note any significant toxicity attributable to radiation. Progression free survival and quality of life could not be pooled due to lack of data.Overall survival was similar between hypofractionated versus conventional radiotherapy in five trials (943 participants), where the HR was 0.95 (95% CI 0.78 to 1.17, P = 0.63), very low GRADE quality evidence. The trials reported that hypofractionated and conventional radiotherapy were well tolerated with mild acute adverse effects. These trials only reported one patient in the hypofractionated arm developing symptomatic radiation necrosis that required surgery. Progression free survival and quality of life could not be pooled due to the lack of data.Overall survival was also similar between hypofractionated versus conventional radiotherapy in the subset of two trials (293 participants) which included 60 years and older participants with glioblastoma. For this category, the HR was 1.16 (95% CI 0.92 to 1.46, P = 0.21), high GRADE quality evidence.There were two trials which compared hyperfractionated radiation therapy versus conventional radiation and one trial which compared accelerated radiation therapy versus conventional radiation. However, the results could not be pooled.The conventionally fractionated radiation therapy regimens were 4500 to 6000 cGy given in 180 to 200 cGy daily fractions, over 5 to 6 weeks.All these trials generally included participants with World Health Organization (WHO) performance status from 0 to 2 and Karnofsky performance status of 50 and higher.The risk of selection bias was generally low among these randomized trials. The number of participants lost to follow-up for the outcome of overall survival was low. Attrition, performance, detection and reporting bias for the outcome of overall survival was low. There was unclear attrition, performance, detection and reporting bias relating to the outcomes of adverse effects, progression free survival and quality of life. AUTHORS' CONCLUSIONS Postoperative conventional daily radiotherapy improves survival for adults with good performance status and HGG as compared to no postoperative radiotherapy.Hypofractionated radiation therapy has similar efficacy for survival as compared to conventional radiotherapy, particularly for individuals aged 60 and older with glioblastoma.There is insufficient data regarding hyperfractionation versus conventionally fractionated radiation (without chemotherapy) and for accelerated radiation versus conventionally fractionated radiation (without chemotherapy).There are HGG subsets who have poor prognosis even with treatment (e.g. glioblastoma histology, older age and poor performance status). These poor prognosis HGG individuals have generally been excluded from the randomised trials based on poor performance status. No randomised trial has compared comfort measures or best supportive care with an active intervention using radiotherapy or chemotherapy in these poor prognosis patients.
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Affiliation(s)
- Luluel Khan
- Radiation Oncology, University of Toronto, 2075 Bayview Avenue, Toronto, ON, Canada, M4N 3M5
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21
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Abstract
ABSTRACT:Objective:To analyze our experience with a second radiosurgical treatment for brain arteriovenous malformations (BAVMs) after an unsuccessful first radiosurgical treatment.Methods:Between 1993 and 2000, 242 patients were treated by the Toronto Sunnybrook Regional Cancer Center using a LINAC system. Fifteen of these patients required a second radiosurgical intervention due to the failure of the first procedure. Data was collected on baseline patient characteristics, BAVM features, radiosurgery treatment plan and outcomes. Brain arteriovenous malformation obliteration was determined by follow-up MRI and angiography and the obliteration prediction index (OPI) calculated according to a previously established formula.Results:The median interval between the first and second treatment was 46 months (range 39-109). The median follow-up after the second procedure was 39 months (range 26 to 72). The mean BAVM volume before the first treatment was 8.9cm3 (range 0.3-21) and before the second treatment was 3.6cm3 (range 0.2-11.6). The mean marginal dose during the first treatment was 18Gy (range 12-25) and during the second treatment was 16Gy (range 12-20). After the second treatment, nine patients had obliteration of their BAVM confirmed by angiography and one patient had obliteration confirmed by MRI, resulting in an obliteration rate of 66.6%, which is very comparable to that predicted by the OPI (65%). After the second treatment two patients had a radiation-induced complication (13.3%).Conclusion:Retreatment of BAVM using a second radiosurgery procedure is a safe and effective option that offers the same rate of success as the initial radiosurgery and an acceptable risk of radiation-induced complication.
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Affiliation(s)
- Javad Mirza-Aghazadeh
- Division of Neurosurgery, Sunnybrook and Women's College Health Science Centre, Department of Radiation Oncology, Toronto-Sunnybrook Regional Cancer Centre, University of Toronto, Ontario, Canada
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Khan L, Breen D, Zhang L, Balogh J, Czarnota G, Lee J, Tsao MN, Barnes EA. Predictors of recurrence after radiotherapy for non-melanoma skin cancer. ACTA ACUST UNITED AC 2014; 21:e326-9. [PMID: 24764714 DOI: 10.3747/co.21.1727] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Predictive factors of recurrence were examined in 448 non-melanoma skin cancers (72% basal cell carcinoma, 28% squamous cell carcinoma) treated with radiotherapy. The overall recurrence rate was 15.8% at a median follow-up of 18.4 months. In multivariate analysis, significant factors for recurrence were age (p = 0.0197), tumour size 2 cm or greater (p = 0.0095), immunosuppression (p = 0.0082), and treatment modality (p = 0.0009).
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Affiliation(s)
- L Khan
- University of Toronto, Toronto, ON
| | - D Breen
- University of Toronto, Toronto, ON
| | - L Zhang
- University of Toronto, Toronto, ON
| | - J Balogh
- University of Toronto, Toronto, ON
| | | | - J Lee
- University of Toronto, Toronto, ON
| | - M N Tsao
- University of Toronto, Toronto, ON
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Tsao MN, Rades D, Wirth A, Lo SS, Danielson BL, Vichare A, Hahn C, Chang EL. International Practice Survey on the Management of Brain Metastases: Third International Consensus Workshop on Palliative Radiotherapy and Symptom Control. Clin Oncol (R Coll Radiol) 2012; 24:e81-92. [PMID: 22794327 DOI: 10.1016/j.clon.2012.03.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 01/27/2012] [Accepted: 03/22/2012] [Indexed: 11/30/2022]
Affiliation(s)
- M N Tsao
- Department of Radiation Oncology, University of Toronto, Odette Cancer Centre, Toronto, Ontario, Canada.
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Follwell MJ, Khu KJ, Cheng L, Xu W, Mikulis DJ, Millar BA, Tsao MN, Laperriere NJ, Bernstein M, Sahgal A. Volume specific response criteria for brain metastases following salvage stereotactic radiosurgery and associated predictors of response. Acta Oncol 2012; 51:629-35. [PMID: 22537310 DOI: 10.3109/0284186x.2012.681066] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND We aimed to derive three-dimensional volume-based (V(3D)) response criteria that approximate those based on Response Evaluation Criteria in Solid Tumours (RECIST) in patients with brain metastases (BM) treated with salvage stereotactic radiosurgery (SRS). MATERIAL AND METHODS Seventy patients with 178 BM were treated with SRS. Each BM was characterised at baseline and at each follow-up MRI according to its widest diameter and V(3D) using ITK-SNAP image segmentation software. RESULTS The median tumour diameter was 1.2 cm (range, 0.2-4.5 cm) and V(3D) was 0.73 cm(3) (range, 0.01-22.7 cm(3)). The V(3D) percent changes that best matched RECIST response criteria were: an increase of ≥71.5% for progressive disease, a ≥58.5% decrease for partial response and a <58.5% decrease or increase of <71.5% for stable disease (k =0.85). A baseline diameter >3.0 cm (p =0.006) and a V(3D) >6.0 cm(3) (p =0.043) predicted for local failure, and a baseline cumulative V(3D) of >3.0 cm(3) (p =0.02) was adversely prognostic for survival. CONCLUSIONS We define 3D volume specific criteria to base response upon for brain metastases treated with salvage SRS. Tumours with a V(3D) of greater than 6 cm(3) are at a higher risk of local failure.
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Affiliation(s)
- Matthew J Follwell
- Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario, Canada
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Tsao MN, Lloyd N, Wong RKS, Chow E, Rakovitch E, Laperriere N, Xu W, Sahgal A. Whole brain radiotherapy for the treatment of newly diagnosed multiple brain metastases. Cochrane Database Syst Rev 2012; 2012:CD003869. [PMID: 22513917 PMCID: PMC6457607 DOI: 10.1002/14651858.cd003869.pub3] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Brain metastases represent a significant healthcare problem. It is estimated that 20% to 40% of patients with cancer will develop metastatic cancer to the brain during the course of their illness. The burden of brain metastases impacts on quality and length of survival. Presenting symptoms include headache (49%), focal weakness (30%), mental disturbances (32%), gait ataxia (21%), seizures (18%), speech difficulty (12%), visual disturbance (6%), sensory disturbance (6%) and limb ataxia (6%).Brain metastases may spread from any primary site. The most common primary site is the lung, followed by the breast then gastrointestinal sites. Eighty-five per cent of brain metastases are found in the cerebral hemispheres, 10% to 15% in the cerebellum and 1% to 3% in the brainstem. Brain radiotherapy is used to treat cancer participants who have brain metastases from various primary malignancies.This is an update to the original review published in Issue 3, 2006. OBJECTIVES To assess the effectiveness and adverse effects of whole brain radiotherapy (WBRT) in adult participants with multiple metastases to the brain. SEARCH METHODS We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 3, 2011), MEDLINE and EMBASE to July 2011. SELECTION CRITERIA Randomized controlled trials (RCTs) comparing WBRT either alone or with other treatments in adults with newly diagnosed multiple metastases to the brain from any primary cancer. Trials of prophylactic WBRT were excluded as well as trials that dealt with surgery or WBRT, or both, for the treatment of single brain metastasis. DATA COLLECTION AND ANALYSIS Two review authors independently assessed trial quality and abstracted information. Adverse effects information was also collected from the trials. MAIN RESULTS Nine RCTs involving 1420 participants were added in this updated review. This updated review now includes a total of 39 trials involving 10,835 participants.Eight published reports (nine RCTs) showed no benefit of altered dose-fractionation schedules as compared to the control fractionation (3000 cGy in 10 fractions daily) of WBRT for overall survival. These studies also showed no improvement in symptom control nor neurologic improvement among the different dose-fractionation schemes as compared to 3000 cGy in 10 daily fractions of WBRT. This updated review includes two trials comparing 4000 cGy in 20 fractions given twice daily versus 2000 cGy in 4 or 5 daily fractions. Overall, there was no survival advantage (hazard ratio (HR) 1.18, 95% confidence interval (CI) 0.89 to 1.56, P = 0.25) with the use of 4000 cGy in 20 fractions given twice daily compared to 2000 cGy in 4 or 5 daily fractions.The addition of radiosensitizers in six RCTs did not confer additional benefit to WBRT in either the overall survival times (HR 1.08, 95% CI 0.98 to 1.18, P = 0.11) or brain tumour response rates (HR 0.87, 95% CI 0.60 to 1.26, P = 0.46).Two RCTs found no benefit in overall survival (HR 0.61, 95% CI 0.27 to 1.39, P = 0.24) with the use of WBRT and radiosurgery boost as compared to WBRT alone for selected participants with multiple brain metastases (up to four brain metastases). Overall, there was a statistically significant improvement in local brain control (HR 0.35, 95% CI 0.20 to 0.61, P = 0.0003) favouring the WBRT and radiosurgery boost arm. Only one trial of radiosurgery boost with WBRT reported an improved Karnofsky performance score outcome and improved ability to reduce the dexamethasone dose.In this updated review, a total of three RCTs reported on selected patients (with up to three or four brain metastases) treated with radiosurgery alone versus WBRT and radiosurgery. Based on two trials, there was no difference in overall survival (HR 0.98, 95% CI 0.71 to 1.35, P = 0.88). The addition of WBRT when added to radiosurgery significantly improved locally treated brain metasatases control (HR 2.61, 95% CI 1.68 to 4.06, P < 0.0001) and distant brain control (HR 2.15, 95% CI 1.55 to 2.99, P < 0.00001). On the other hand, one trial concluded that patients treated with WBRT and radiosurgery boost were significantly more likely to show a decline in learning and memory function as compared to those treated with radiosurgery alone.One RCT examined the use of WBRT and prednisone versus prednisone alone and produced inconclusive results. AUTHORS' CONCLUSIONS None of the RCTs with altered WBRT dose-fractionation schemes as compared to standard (3000 cGy in 10 daily fractions or 2000 cGy in 4 or 5 daily fractions) found a benefit in terms of overall survival, neurologic function, or symptom control.The use of radiosensitizers or chemotherapy in conjunction with WBRT remains experimental.Radiosurgery boost with WBRT may improve local disease control in selected participants as compared to WBRT alone, although survival remains unchanged for participants with multiple brain metastases.This updated review now includes a total of three RCTs examining the use of radiosurgery alone versus WBRT and radiosurgery. The addition of WBRT to radiosurgery improves local and distant brain control but there is no difference in overall survival. Patients treated with radiosurgery alone were found to have better neurocognitive outcomes in one trial as compared to patients treated with WBRT and radiosurgery.The benefit of WBRT as compared to supportive care alone has not been studied in RCTs. It may be that supportive care alone, without WBRT, is appropriate for some participants, particularly those with advanced disease and poor performance status.
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Affiliation(s)
- May N Tsao
- Department ofRadiationOncology,OdetteCancerCentre,Toronto,Canada.
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Tsao MN, Rades D, Wirth A, Lo SS, Danielson BL, Gaspar LE, Sperduto PW, Vogelbaum MA, Radawski JD, Wang JZ, Gillin MT, Mohideen N, Hahn CA, Chang EL. Radiotherapeutic and surgical management for newly diagnosed brain metastasis(es): An American Society for Radiation Oncology evidence-based guideline. Pract Radiat Oncol 2012; 2:210-225. [PMID: 25925626 PMCID: PMC3808749 DOI: 10.1016/j.prro.2011.12.004] [Citation(s) in RCA: 412] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 12/09/2011] [Accepted: 12/15/2011] [Indexed: 12/25/2022]
Abstract
Purpose To systematically review the evidence for the radiotherapeutic and surgical management of patients newly diagnosed with intraparenchymal brain metastases. Methods and Materials Key clinical questions to be addressed in this evidence-based Guideline were identified. Fully published randomized controlled trials dealing with the management of newly diagnosed intraparenchymal brain metastases were searched systematically and reviewed. The U.S. Preventative Services Task Force levels of evidence were used to classify various options of management. Results The choice of management in patients with newly diagnosed single or multiple brain metastases depends on estimated prognosis and the aims of treatment (survival, local treated lesion control, distant brain control, neurocognitive preservation). Single brain metastasis and good prognosis (expected survival 3 months or more): For a single brain metastasis larger than 3 to 4 cm and amenable to safe complete resection, whole brain radiotherapy (WBRT) and surgery (level 1) should be considered. Another alternative is surgery and radiosurgery/radiation boost to the resection cavity (level 3). For single metastasis less than 3 to 4 cm, radiosurgery alone or WBRT and radiosurgery or WBRT and surgery (all based on level 1 evidence) should be considered. Another alternative is surgery and radiosurgery or radiation boost to the resection cavity (level 3). For single brain metastasis (less than 3 to 4 cm) that is not resectable or incompletely resected, WBRT and radiosurgery, or radiosurgery alone should be considered (level 1). For nonresectable single brain metastasis (larger than 3 to 4 cm), WBRT should be considered (level 3). Multiple brain metastases and good prognosis (expected survival 3 months or more): For selected patients with multiple brain metastases (all less than 3 to 4 cm), radiosurgery alone, WBRT and radiosurgery, or WBRT alone should be considered, based on level 1 evidence. Safe resection of a brain metastasis or metastases causing significant mass effect and postoperative WBRT may also be considered (level 3). Patients with poor prognosis (expected survival less than 3 months): Patients with either single or multiple brain metastases with poor prognosis should be considered for palliative care with or without WBRT (level 3). It should be recognized, however, that there are limitations in the ability of physicians to accurately predict patient survival. Prognostic systems such as recursive partitioning analysis, and diagnosis-specific graded prognostic assessment may be helpful. Conclusions Radiotherapeutic intervention (WBRT or radiosurgery) is associated with improved brain control. In selected patients with single brain metastasis, radiosurgery or surgery has been found to improve survival and locally treated metastasis control (compared with WBRT alone).
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, University of Toronto, Odette Cancer Centre, Toronto, Ontario, Canada.
| | - Dirk Rades
- Department of Radiation Oncology, University Hospital Schleswig-Holstein, Luebeck, Germany (ESTRO representative)
| | - Andrew Wirth
- Peter MacCallum Cancer Center, Trans Tasman Radiation Oncology Group (TROG), East Melbourne, Australia
| | - Simon S Lo
- Department of Radiation Oncology, Case Western Reserve University, University Hospitals Case Medical Center, Cleveland, Ohio
| | - Brita L Danielson
- Department of Radiation Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Canada (CARO representative)
| | - Laurie E Gaspar
- Department of Radiation Oncology, University of Colorado, Aurora, Colorado
| | - Paul W Sperduto
- University of Minnesota Gamma Knife Center and Minneapolis Radiation Oncology, Minneapolis, Minnesota
| | | | | | - Jian Z Wang
- Department of Radiation Oncology, Ohio State University, Columbus, Ohio (deceased)
| | - Michael T Gillin
- Department of Radiation Oncology, M.D. Anderson Cancer Center, Houston, Texas
| | - Najeeb Mohideen
- Department of Radiation Oncology, Northwest Community Hospital, Arlington Heights, Illinois
| | - Carol A Hahn
- Department of Radiation Oncology, Duke University Medical School, Durham, North Carolina
| | - Eric L Chang
- Department of Radiation Oncology, University of Southern California Keck School of Medicine, Los Angeles, California
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Barnes EA, Chow E, Tsao MN, Bradley NM, Doyle M, Li K, Lam K, Danjoux C. Physician expectations of treatment outcomes for patients with brain metastases referred for whole brain radiotherapy. Int J Radiat Oncol Biol Phys 2010; 76:187-92. [PMID: 19386437 DOI: 10.1016/j.ijrobp.2009.01.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 01/19/2009] [Accepted: 01/21/2009] [Indexed: 11/26/2022]
Abstract
PURPOSE Patients with advanced cancer are referred to our Rapid Response Radiotherapy Program for quick access to palliative radiotherapy. The primary objective of this prospective study was to determine the physician expectations of the treatment outcomes for patients with brain metastases referred for whole brain radiotherapy (WBRT). The secondary objectives were to determine the factors influencing the expectations and to examine the accuracy of the physician-estimated patient survival. METHODS AND MATERIALS Patients were identified during a 17-month period. The referring physicians were sent a survey by facsimile to be completed and returned before the patient consultation. Information was sought on the patient's disease status, the physician's expectations of WBRT, the estimated patient survival and performance status, and physician demographic data. RESULTS A total of 137 surveys were sent out, and the overall response rate was 57.7%. The median patient age was 66 years (range, 35-87), 78.5% had multiple brain metastases, 42.3% had a controlled primary tumor, and 62.3% had extracranial disease. WBRT was thought to stabilize neurologic symptoms, improve quality of life, and allow for a Decadron (dexamethasone) taper by > or =94.9% of the referring physicians; 87.0% thought WBRT would improve performance status; 77.9% thought it would improve neurologic symptoms; and 40.8% thought it would improve survival. The referring physicians estimated patient survival as a median of 6.0 months; however, the actual survival was a median of 2.5 months, for a median individual difference of 1.9 months (p < .0001). CONCLUSION Physicians referring patients with brain metastases for consideration of WBRT are often overly optimistic when estimating the clinical benefit of the treatment and overestimate patient survival. These findings highlight the need for education and additional research in this field.
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Affiliation(s)
- Elizabeth A Barnes
- Rapid Response Radiotherapy Program, Department of Radiation Oncology, Odette Cancer Centre, Toronto, ON, Canada.
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Lightstone AW, Tsao MN, Basran PS, Chan G, Pang G, Ma L, Lochray F, Sahgal A. SU-FF-T-536: Cone Beam CT Observation of Intra-Fraction Shift During Intracranial Treatments for Patients Held in a Mask. Med Phys 2009. [DOI: 10.1118/1.3182034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Bradley NME, Husted J, Sey MSL, Sinclair E, Li KK, Husain AF, Danjoux C, Barnes EA, Tsao MN, Barbera L, Harris K, Chiu H, Doyle M, Chow E. Did the pattern of practice in the prescription of palliative radiotherapy for the treatment of uncomplicated bone metastases change between 1999 and 2005 at the rapid response radiotherapy program? Clin Oncol (R Coll Radiol) 2008; 20:327-36. [PMID: 18276125 PMCID: PMC7126631 DOI: 10.1016/j.clon.2008.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Revised: 12/19/2007] [Accepted: 12/20/2007] [Indexed: 01/15/2023]
Abstract
AIMS Since 1999, randomised clinical trials and meta-analyses have reported equal efficacy of pain relief from single- and multiple-fraction radiotherapy for bone metastases. A number of factors, including limited radiotherapy resources, waiting times, and patient convenience, suggest single fraction to be the treatment of choice for patients. However, international patterns of practice indicate that multiple fractions are still commonly used. This study examined whether dose-fractionation schemes used for the treatment of bone metastases at the Rapid Response Radiotherapy Program (RRRP) at the Odette Cancer Centre have changed since 1999. MATERIALS AND METHODS A retrospective review of the prospective RRRP database and hospital records were conducted for all patients treated with palliative radiotherapy for uncomplicated bone metastases at the RRRP in 1999 (or baseline), 2001, 2004 and from 1 January to 31 July 2005. Data were collected on patient demographics and clinical characteristics. RESULTS Of the 693 patients, 65 and 35% were prescribed single fraction (predominantly single 8 Gy) and multiple fractions (predominantly 20 Gy/five fractions), respectively. The administration of single treatments generally increased over time, from 51% in 1999 to 66% in 2005 (P=0.0001). On the basis of multiple logistic regression analyses, patients were more likely to be prescribed single-fraction radiotherapy if they had prostate cancer, had a poorer performance status, were treated to the limbs, hips, shoulders, pelvis, ribs, scapula, sternum, or clavicle (compared with the spine), were treated by a radiation oncologist who had been trained in earlier years, and who were treated after 1999. CONCLUSIONS Between 1999 and 2005, the use of single-fraction radiotherapy increased, corresponding to publications showing equal efficacy of pain relief between single and multiple fractions in the management of uncomplicated bone metastases. However, about a third of patients still received multiple fractions.
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Affiliation(s)
- N M E Bradley
- Department of Health Studies and Gerontology, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario, Canada
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Andrade-Souza YM, Ramani M, Beachey DJ, Scora D, Tsao MN, Terbrugge K, Schwartz ML. Liquid embolisation material reduces the delivered radiation dose: a physical experiment. Acta Neurochir (Wien) 2008; 150:161-4; discussion 164. [PMID: 18213438 DOI: 10.1007/s00701-007-1482-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Accepted: 12/04/2007] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To test a new hypothesis that the glue/contrast admixture used for embolisation reduces the dose delivered to AVMs using an experimental model. METHOD A model was created using a block of "solid water" (6 x 5 x 2 cm) with twelve wells of different depths. Different concentrations of the glue admixture (Enbucrilate + Lipiodol) were used. The model was irradiated using a 5MV beam with a clinical LINAC system and the dose was checked upstream and downstream. Dose was measured using Kodak XV film, a Vidar 16 bit film scanner and software for therapeutic film dosimetry measurements (RIT software). RESULTS The radiation dose varied with the distance beyond the glue solid water interface. For distances of 0, 2 and 5 mm to the film, the mean reduction was 13.65% (SD = 2.94), 6.87% (SD = 1.95) and 1.75% (SD = 1.14), respectively. There was also correlation with the Lipiodol concentration in the mixture. The maximum reductions for 80, 50 and 20% Lipiodol concentrations were 16.1% (SD = 1.32), 14.85% (SD = 0.98) and 10% (SD = 1.21), respectively. There was no correlation between the glue depth and the dose delivered. CONCLUSION The hypothesis that the glue mixture used for embolisation reduces the radiation dose delivered was experimentally confirmed with this study.
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Doyle M, Bradley NME, Li K, Sinclair E, Lam K, Chan G, Chow E, Barnes EA, Danjoux C, Tsao MN. Quality of Life in Patients with Brain Metastases Treated with a Palliative Course of Whole-Brain Radiotherapy. J Palliat Med 2007; 10:367-74. [PMID: 17472508 DOI: 10.1089/jpm.2006.0202] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The primary objective of this study was to assess whether there was an improvement in quality of life for patients with brain metastases as measured 1 and 2 months after a course of whole-brain radiotherapy. The secondary objective was to assess the level of agreement between patient and proxy quality of life scores. METHODS AND MATERIALS Sixty patients with brain metastases and their proxy completed the Functional Assessment of Cancer Therapy-Brain (FACT-BR) questionnaire independently. Proxies were given instructions to answer from the patient's perspective. Quality-of-life assessments were conducted at baseline, 1 month, and 2 months after completion of whole-brain radiotherapy. Paired t tests with Bonferroni adjustment for multiple comparisons were calculated to detect significant differences in global quality-of-life scores. Lin's concordance correlation coefficient measured agreement between patient and proxy quality-of-life ratings. RESULTS No significant difference was detected in overall quality of life after whole-brain radiotherapy. At 2 months after whole-brain radiotherapy, there was a trend toward worsening general and brain specific quality-of-life scores. There was poor concordance between patients and their proxies for all quality-of-life domains at baseline. CONCLUSION At 2 months after whole-brain radiotherapy, there was a trend toward worsening general and brain specific quality-of-life scores. Proxy rating of patients' quality of life showed poor concordance at baseline.
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Affiliation(s)
- Megan Doyle
- Department of Radiation Oncology, Toronto-Sunnybrook Regional Cancer Centre, Toronto, Ontario, Canada
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Andrade-Souza YM, Ramani M, Scora D, Tsao MN, terBrugge K, Schwartz ML. EMBOLIZATION BEFORE RADIOSURGERY REDUCES THE OBLITERATION RATE OF ARTERIOVENOUS MALFORMATIONS. Neurosurgery 2007; 60:443-51; discussion 451-2. [PMID: 17327788 DOI: 10.1227/01.neu.0000255347.25959.d0] [Citation(s) in RCA: 197] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
OBJECTIVE
To evaluate the arteriovenous malformation (AVM) obliteration rate and the clinical outcome after radiosurgery in patients with and without previous embolization.
METHODS
Of 244 patients who underwent linear accelerator radiosurgery for AVMs at the Sunnybrook Health Sciences Centre between 1989 and 2000, 61 patients had embolization before radiosurgery and complete follow-up for at least 3 years. For 47 of these 61 patients (Group A, embolization plus radiosurgery), we were able to find 47 matching patients without previous embolization (Group B, radiosurgery alone). This group of matching patients had the same AVM volume (after embolization in Group A), location, and marginal dose. The radiosurgery-based AVM score and the obliteration prediction index were calculated.
RESULTS
The median follow-up period was 44 months. Nidus obliteration was achieved in 22 patients in Group A (47%) and 33 patients in Group B (70%, P = 0.036). Permanent deficit related to hemorrhage or radiation occurred in three patients (6%) in Group A and three patients (6%) in Group B. During the first 3 years after radiosurgery, two patients (4%) in Group A experienced hemorrhage; in Group B, five patients (11%) experienced hemorrhage (P = 0.2). In Group B, two patients (4%) died and two patients (4%) had their AVM surgically removed. Both deaths were related to hemorrhage during the latency period. The excellent outcome (obliteration plus no deficit) in Group A was 47% compared with 64% in Group B (P = 0.146). There was no difference in the obliteration prediction index and the radiosurgery-based AVM score between Groups A and B. The predicted rates of obliteration and excellent outcome were 55 and 62.5%, respectively, according to the obliteration prediction index and the radiosurgery-based AVM score.
CONCLUSION
Embolization before radiosurgery significantly decreases the obliteration rate, even in AVMs with the same volume, location, and marginal dose. Although an excellent outcome rate was higher in the group without embolization, this was not statistically significant.
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Affiliation(s)
- Yuri M Andrade-Souza
- Division of Neurosurgery, University of Toronto, Sunnybrook Health Sciences Centre, Toronto Western Hospital, Toronto, Canada
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Zadeh G, Andrade-Souza YM, Tsao MN, Scora D, Armstrong D, Humphreys R, Rutka J, Drake J, Dirks P, Schwartz ML. Pediatric arteriovenous malformation: University of Toronto experience using stereotactic radiosurgery. Childs Nerv Syst 2007; 23:195-9. [PMID: 17115227 DOI: 10.1007/s00381-006-0207-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2005] [Revised: 04/07/2006] [Indexed: 10/23/2022]
Abstract
INTRODUCTION AND BACKGROUND Arteriovenous malformations (AVMs) are congenital vascular lesions of the brain, which behave differently in pediatric population compared to adults. Treatment of pediatric AVMs includes a combination of microsurgery, embolization and radiation therapies. However, the role of radiosurgery in the treatment of pediatric AVMs is not fully accepted because of concerns regarding the long-term effects of radiation on the pediatric brain. DISCUSSION In this study, we review our experience at the University of Toronto with treating pediatric AVMs using linear accelerator-based (LINAC) radiosurgery over the past 15 years. We report our results, obliteration rates, and complications on a total of 40 patients. In addition, we provide a review of series published to date combined with our own results to determine whether radiosurgery is a safe and reasonable treatment modality for pediatric AVMs.
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Affiliation(s)
- Gelareh Zadeh
- Division of Neurosurgery, Sunnybrook Health Sciences Centre (SHSC), Suite A129, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
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Abstract
Object
The authors reviewed the radiosurgical outcomes in patients with arteriovenous malformations (AVMs) located in the rolandic area, including the primary motor and sensory gyri.
Methods
The study population consisted of 38 patients with rolandic-area AVMs who underwent linear accelerator radiosurgery at the University of Toronto between 1989 and 2000. Obliteration rate, risk of hemorrhage during the latency period, radiation-induced complications, seizure control, and functional status were evaluated. Patients were also divided into two subgroups according to AVM volume (< 3 cm3 and ≥ 3 cm3).
Patients were followed up for a median of 42.4 months (range 30–103 months), and the median age of the patients was 40 years (range 12–67 years). The median AVM volume was 8.1 cm3 (range 0.32–21, mean 8.32 cm3), and the median dose at the tumor margin was 15 Gy (range 15–22, mean 16.8 Gy). The risk of hemorrhage after radiosurgery was 5.3% for the 1st year, 2.6% for the 2nd, and 0% for the 3rd. Two patients (5.3%) sustained adverse effects related to radiation for more than 6 months. Complete nidus obliteration after a single radiosurgical treatment was achieved in 23 patients (60.5%). The obliteration rate for AVMs smaller than 3 cm3 was 83.3% (10 of 12) and that for AVMs larger than or equal to 3 cm3 was 50% (13 of 26). Among the patients who had seizures as the initial presentation, 51.8% were free of seizures after radiosurgery and the seizure pattern improved in 40.7% during the 3rd and last year of follow up. Overall, excellent results (obliteration and no new or worsening neurological deficit) can be achieved in approximately 60% of patients. This percentage varies according to the AVM size and can reach 83% in patients with AVMs smaller than 3 cm3.
Conclusions
Radiosurgery is a safe and effective treatment for people with rolandic AVMs. The low rate of morbidity associated with radiosurgery, compared with other treatments, indicates that this method may be the first choice for patients with AVMs located in this area.
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Affiliation(s)
- Yuri M Andrade-Souza
- Division of Neurosurgery, Sunnybrook and Women's College Health Sciences Centre, Toronto, Ontario, Canada.
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Abstract
BACKGROUND Brain radiotherapy is used to treat cancer patients who have brain metastases resulting from various primary malignancies. OBJECTIVES To assess the effectiveness and adverse effects of whole brain radiotherapy (WBRT) in adult patients with multiple metastases to the brain. SEARCH STRATEGY CENTRAL (The Cochrane Library), MEDLINE, EMBASE, CANCERLIT, and CINAHL were searched. SELECTION CRITERIA Randomized controlled trials (RCTs) in which adult patients with multiple metastases to the brain from any primary cancer and treated with WBRT were included. Trials of prophylactic WBRT were excluded as well as trials that dealt with surgery or WBRT, or both, for the treatment of a single brain metastasis. DATA COLLECTION AND ANALYSIS Two review authors independently abstracted information for each predetermined outcome: overall survival at six months, intracranial progression-free duration, local brain response, local brain control, quality of life, symptom control, neurological function, and the proportion of patients able to reduce the daily dexamethasone dose. Adverse effects were also collected. MAIN RESULTS Eight published reports (nine trials) showed no benefit of altered dose-fractionation schedules as compared to control fractionation (3000 cGy in 10 fractions) of WBRT on the probability of survival at six months. These studies also showed no difference in symptom control nor neurologic improvement among the different dose-fractionation schemes. The addition of radiosensitizers, in five RCTs, did not confer additional benefit to WBRT in either overall median survival times or brain tumor response rates. The addition of the radiosensitizer motexafin gadolinium did not improve quality of life nor time to neurologic progression overall. For the radiosensitizer misonidazole, there was no improvement in Karnofsky performance score outcomes. Three RCTs found no benefit in overall survival with the use of WBRT and a radiosurgery boost as compared to WBRT alone for selected patients with multiple brain metastases (up to four brain metastases). Overall, however, there was a statistically significant improvement in local brain control favoring the whole brain radiotherapy and radiosurgery boost arm. Only one trial of radiosurgery boost with WBRT reported an improved Karnofsky performance score outcome and improved ability to reduce dexamethasone dose. One RCT examined the use of WBRT and prednisone versus prednisone alone and produced inconclusive results. AUTHORS' CONCLUSIONS None of the RCTs with altered dose-fractionation schemes as compared to standard delivery (3000 cGy in ten fractions) found a benefit in terms of overall survival, neurologic function, or symptom control. The use of radiosensitizers or chemotherapy in conjunction with WBRT remains experimental. A radiosurgery boost with WBRT may improve local disease control in selected patients, although survival remains unchanged. The benefit of WBRT as compared to supportive care alone has not been studied in RCTs. It may be that supportive care alone, without WBRT, may be appropriate for some patients, particularly those with advanced disease and poor performance status.
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Affiliation(s)
- M N Tsao
- Toronto-Sunnybrook Regional Cancer Centre, Department of Radiation Oncology, 2075 Bayview Avenue, Toronto, Ontario, Canada M4N 3M5.
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Bradley NM, Chow E, Tsao MN, Danjoux C, Barnes EA, Hayter C, Holden L, Yau V, Li K, Doyle M, Sinclair E. Reasons for Poor Accrual in Palliative Radiation Therapy Research Studies. ACTA ACUST UNITED AC 2006; 3:110-9. [DOI: 10.3816/sct.2006.n.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Mehta MP, Tsao MN, Whelan TJ, Morris DE, Hayman JA, Flickinger JC, Mills M, Rogers CL, Souhami L. The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for brain metastases. Int J Radiat Oncol Biol Phys 2005; 63:37-46. [PMID: 16111570 DOI: 10.1016/j.ijrobp.2005.05.023] [Citation(s) in RCA: 202] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Accepted: 05/20/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE To systematically review the evidence for the use of stereotactic radiosurgery in adult patients with brain metastases. METHODS Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncology (ASCO) (1997-2004), ASTRO (1997-2004), and the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence. RESULTS For patients with newly diagnosed brain metastases, managed with whole-brain radiotherapy alone vs. whole-brain radiotherapy and radiosurgery boost, there were three randomized controlled trials, zero prospective studies, and seven retrospective series (which satisfied inclusion criteria). For patients with up to three (<4 cm) newly diagnosed brain metastases (and in one study up to four brain metastases), radiosurgery boost with whole-brain radiotherapy significantly improves local brain control rates as compared with whole-brain radiotherapy alone (Level I-III evidence). In one large randomized trial, survival benefit with whole-brain radiotherapy was observed in patients with single brain metastasis. In this trial, an overall increased ability to taper down on steroid dose and an improvement in Karnofsky performance status was seen in patients who were treated with radiosurgery boost as compared with patients treated with whole-brain radiotherapy alone. However, Level I evidence regarding overall quality of life outcomes using a validated instrument has not been reported. All randomized trials showed improved local control with the addition of radiosurgery to whole-brain radiotherapy. For patients with multiple brain metastases, there is no overall survival benefit with the use of radiosurgery boost to whole-brain radiotherapy (Level I-III evidence). Radiosurgery boost is associated with a small risk of early or late toxicity. In patients treated with radiosurgery alone (withholding whole-brain radiotherapy) as initial treatment, there were 2 randomized trials, 2 prospective cohort studies, and 16 retrospective series. There is Level I to Level III evidence that the use of radiosurgery alone does not alter survival as compared to the use of whole-brain radiotherapy. However, there is Level I to Level III evidence that omission of whole-brain radiotherapy results in poorer intracranial disease control, both local and distant (defined as remaining brain, outside the radiosurgery field). Quality of life outcomes have not been adequately reported. Radiosurgery is associated with a small risk of early or late toxicity. Radiosurgery as salvage for patients with brain metastases was reported in zero randomized trials, one prospective study, and seven retrospective series. CONCLUSIONS Based on Level I-III evidence, for selected patients with small (up to 4 cm) brain metastases (up to three in number and four in one randomized trial), the addition of radiosurgery boost to whole-brain radiotherapy improves brain control as compared with whole-brain radiotherapy alone. In patients with a single brain metastasis, radiosurgery boost with whole-brain radiotherapy improves survival. There is a small risk of toxicity associated with radiosurgery boost as compared with whole-brain radiotherapy alone. In selected patients treated with radiosurgery alone for newly diagnosed brain metastases, overall survival is not altered. However, local and distant brain control is significantly poorer with omission of upfront whole-brain radiotherapy (Level I-III evidence). Whether neurocognition or quality of life outcomes are different between initial radiosurgery alone vs. whole-brain radiotherapy (with or without radiosurgery boost) is unknown, because this has not been adequately tested. There was no statistically significant difference in overall toxicity between those treated with radiosurgery alone vs. whole-brain radiotherapy and radiosurgery boost based on an interim report from one randomized study. There is insufficient evidence as to the clinical benefit/risks radiosurgery used in the setting of recurrent or progressive brain metastases, although radiographic responses are well-documented.
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Affiliation(s)
- Minesh P Mehta
- The American Society for Therapeutic Radiology and Oncology, Fairfax, VA 22033, USA
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Andrade-Souza YM, Zadeh G, Ramani M, Scora D, Tsao MN, Schwartz ML. Testing the radiosurgery-based arteriovenous malformation score and the modified Spetzler—Martin grading system to predict radiosurgical outcome. J Neurosurg 2005; 103:642-8. [PMID: 16266046 DOI: 10.3171/jns.2005.103.4.0642] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object. The aim of this study was to validate the radiosurgery-based arteriovenous malformation (AVM) score and the modified Spetzler—Martin grading system to predict radiosurgical outcome.
Methods. One hundred thirty-six patients with brain AVMs were randomly selected. These patients had undergone a linear accelerator radiosurgical procedure at a single center between 1989 and 2000. Patients were divided into four groups according to an AVM score, which was calculated from the lesion volume, lesion location, and patient age (Group 1, AVM score < 1; Group 2, AVM score 1–1.49; Group 3, AVM score 1.5–2; and Group 4, AVM score > 2). Patients with a Spetzler—Martin Grade III AVM were divided into Grades IIIA (lesion > 3 cm) and IIIB (lesion < 3 cm). Sixty-two female (45.6%) and 74 male (54.4%) patients with a median age of 37.5 years (mean 37.5 years, range 5–77 years) were followed up for a median of 40 months. The median tumor margin dose was 15 Gy (mean 17.23 Gy, range 15–25 Gy). The proportions of excellent outcomes according to the AVM score were as follows: 91.7% for Group 1, 74.1% for Group 2, 60% for Group 3, and 33.3% for Group 4 (chi-square test, degrees of freedom (df) = 3, p < 0.001). Based on the modified Spetzler—Martin system, Grade I lesions had 88.9% excellent results; Grade II, 69.6%; Grade IIIB, 61.5%; and Grades IIIA and IV, 44.8% (chi-square test, df = 3, p = 0.047).
Conclusions. The radiosurgery-based AVM score can be used accurately to predict excellent results following a single radiosurgical treatment for AVM. The modified Spetzler—Martin system can also predict radiosurgical results for AVMs, thus making it possible to use this system while deciding between surgery and radiosurgery.
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Affiliation(s)
- Yuri M Andrade-Souza
- Division of Neurosurgery and Department of Radiation Oncology, Sunnybrook and Women's College Health Sciences Center, University of Toronto, Ontario, Canada
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Tsao MN, Mehta MP, Whelan TJ, Morris DE, Hayman JA, Flickinger JC, Mills M, Rogers CL, Souhami L. The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for malignant glioma. Int J Radiat Oncol Biol Phys 2005; 63:47-55. [PMID: 16111571 DOI: 10.1016/j.ijrobp.2005.05.024] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Accepted: 05/20/2005] [Indexed: 11/18/2022]
Abstract
PURPOSE To systematically review the evidence for the use of stereotactic radiosurgery or stereotactic fractionated radiation therapy in adult patients with malignant glioma. METHODS Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncology (1997-2004), ASTRO (1997-2004), and the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence. RESULTS For patients with newly diagnosed malignant glioma, radiosurgery as boost therapy with conventional external beam radiation was examined in one randomized trial, five prospective cohort studies, and seven retrospective series. There is Level I evidence that the use of radiosurgery boost followed by external beam radiotherapy and carmustine (BCNU) does not confer benefit with respect to overall survival, quality of life, or patterns of failure as compared with external beam radiotherapy and BCNU. There is Level I-III evidence of toxicity associated with radiosurgery boost as compared with external beam radiotherapy alone. The results of the prospective and retrospective studies may be influenced by selection bias. Radiosurgery used as salvage for recurrent or progressive malignant glioma after conventional external beam radiotherapy failure was reported in zero randomized trials, three prospective cohort studies, and five retrospective series. The available data are sparse and insufficient to make absolute recommendations. Stereotactic fractionated radiation therapy has been reported as boost therapy with external beam radiotherapy for patients with newly diagnosed malignant glioma in only three prospective studies. As primary therapy alone without conventional external beam radiotherapy for newly diagnosed malignant glioma patients, stereotactic fractionated radiation therapy has been reported in only one prospective study. There were only three prospective series and two retrospective studies reported for patients with recurrent or progressive malignant glioma. CONCLUSIONS For patients with malignant glioma, there is Level I-III evidence that the use of radiosurgery boost followed by external beam radiotherapy and BCNU does not confer benefit in terms of overall survival, local brain control, or quality of life as compared with external beam radiotherapy and BCNU. The use of radiosurgery boost is associated with increased toxicity. For patients with malignant glioma, there is insufficient evidence regarding the benefits/harms of using radiosurgery at the time progression or recurrence. There is also insufficient evidence regarding the benefits/harms in the use of stereotactic fractionated radiation therapy for patients with newly diagnosed or progressive/recurrent malignant glioma.
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Affiliation(s)
- May N Tsao
- The American Society for Therapeutic Radiology and Oncology, Fairfax, VA 22033, USA
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Tsao MN, Lloyd NS, Wong RKS, Rakovitch E, Chow E, Laperriere N. Radiotherapeutic management of brain metastases: A systematic review and meta-analysis. Cancer Treat Rev 2005; 31:256-73. [PMID: 15951117 DOI: 10.1016/j.ctrv.2005.04.007] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The management of brain metastases is a significant health care problem. An estimated 20-40% of cancer patients will develop metastatic cancer to the brain during the course of their illness. METHODS A systematic review of randomized trials on adult cancer patients with single or multiple brain metastases from cancer of any histology was conducted. Eligible studies investigated external beam radiotherapy or radiosurgery in one of the study arms. Outcomes of interest included survival, intracranial progression-free duration, response of brain metastases to therapy, quality of life, symptom control, neurological function, and toxicity. RESULTS Twenty-seven trials were included in this systematic review of the evidence. Pooled results from three randomized trials of surgical excision combined with whole brain radiotherapy (WBRT) showed no improvement in overall survival as compared to WBRT alone in patients with single brain metastasis. One randomized study of postoperative WBRT following excision of a single brain metastasis versus surgery alone detected a significant reduction in intracranial tumour recurrence rates but no corresponding difference in overall survival. Nine trials of altered dose-fractionation schedules compared to a standard control fractionation schedule (3000 cGy in 10 fractions) of WBRT showed no difference in probability of survival at 6 months. The addition of radiosensitizers, as assessed in five trials, did not confer additional benefit to WBRT in terms of overall survival or the frequency of brain metastases response. Three trials examined the use of WBRT and radiosurgery boost versus WBRT alone in selected patients with brain metastases. Overall survival did not improve for patients with multiple brain metastases. However, one trial reported an improvement in survival for patients with single brain metastasis treated with WBRT and radiosurgery boost. One older randomized trial examined the use of WBRT versus supportive care alone (using oral prednisone). Results were not conclusive. CONCLUSION For patients with a single brain metastasis, good performance status, and minimal or no evidence of extracranial disease, surgical excision and postoperative WBRT improves survival (as compared to WBRT alone). There may be a small survival advantage associated with the use of radiosurgery boost and WBRT as compared to WBRT alone in selected patients with a single brain metastasis. There is no difference in overall survival or in neurologic function improvement with the use of altered whole brain dose-fractionation schedules as compared to standard fractionation schedules (3000 cGy in 10 fractions or 2000 cGy in 5 fractions). There is no survival benefit associated with the use of radiosurgery boost and WBRT versus WBRT alone in patients with multiple brain metastases. Currently, neither chemotherapy nor radiosensitizers show a clear benefit in the objective parameters of survival and progression-free survival. For patients with poor performance status and active extracranial disease, steroids and supportive care are an option.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Toronto-Sunnybrook Regional Cancer Centre, 2075 Bayview Avenue, Toronto, Ont., Canada M4N 3M5.
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Tsao MN, Lloyd NS, Wong RKS. Clinical practice guideline on the optimal radiotherapeutic management of brain metastases. BMC Cancer 2005; 5:34. [PMID: 15807895 PMCID: PMC1090562 DOI: 10.1186/1471-2407-5-34] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Accepted: 04/04/2005] [Indexed: 05/02/2023] Open
Abstract
BACKGROUND An evidence-based clinical practice guideline on the optimal radiotherapeutic management of single and multiple brain metastases was developed. METHODS A systematic review and meta-analysis was performed. The Supportive Care Guidelines Group formulated clinical recommendations based on their interpretation of the evidence. External review of the report by Ontario practitioners was obtained through a mailed survey, and final approval was obtained from Cancer Care Ontario's Practice Guidelines Coordinating Committee (PGCC). RESULTS One hundred and nine Ontario practitioners responded to the survey (return rate 44%). Ninety-six percent of respondents agreed with the interpretation of the evidence, and 92% agreed that the report should be approved. Minor revisions were made based on feedback from external reviewers and the PGCC. The PGCC approved the final practice guideline report. CONCLUSIONS For adult patients with a clinical and radiographic diagnosis of brain metastases (single or multiple) we conclude that: surgical excision should be considered for patients with good performance status, minimal or no evidence of extracranial disease, and a surgically accessible single brain metastasis. Postoperative whole brain radiotherapy (WBRT) should be considered to reduce the risk of tumour recurrence for patients who have undergone resection of a single brain metastasis. Radiosurgery boost with WBRT may improve survival in select patients with unresectable single brain metastases. The whole brain should be irradiated for multiple brain metastases. Standard dose-fractionation schedules are 3000 cGy in 10 fractions or 2000 cGy in 5 fractions. Radiosensitizers are not recommended outside research studies. In select patients, radiosurgery may be considered as boost therapy with WBRT to improve local tumour control. Radiosurgery boost may improve survival in select patients. Chemotherapy as primary therapy or chemotherapy with WBRT remains experimental. Supportive care is an option but there is a lack of Level 1 evidence as to which subsets of patients should be managed with supportive care alone. Qualifying statements addressing factors to consider when applying these recommendations are provided in the full report. The rigorous development, external review and approval process has resulted in a practice guideline that is strongly endorsed by Ontario practitioners.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Toronto-Sunnybrook Regional Cancer Centre, Toronto, Ontario, Canada
| | - Nancy S Lloyd
- Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada
| | - Rebecca KS Wong
- Department of Radiation Oncology and the Princess Margaret Hospital, University of Toronto, Toronto, Ontario, Canada
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Andrade-Souza YM, Zadeh G, Scora D, Tsao MN, Schwartz ML. Radiosurgery for Basal Ganglia, Internal Capsule, and Thalamus Arteriovenous Malformation: Clinical Outcome. Neurosurgery 2005; 56:56-63; discussion 63-4. [PMID: 15617586 DOI: 10.1227/01.neu.0000145797.35968.ed] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Accepted: 09/10/2004] [Indexed: 11/19/2022] Open
Abstract
Abstract
OBJECTIVE:
Radiosurgery is accepted as the first option for treating deep arteriovenous malformations (AVMs), although the clinical outcome in this subgroup of brain AVMs is not well studied. The objective of this study is to review our experience with radiosurgical treatment for these AVMs.
METHODS:
Between October 1989 and December 2000, 45 patients with deep AVMs (including basal ganglia, internal capsule, and thalamus) underwent stereotactic radiosurgery. Three patients were lost to follow-up and therefore were excluded from this study. Patient characteristics and outcomes were collected and analyzed. The obliteration prediction index and the radiosurgery-based AVM score were calculated and tested.
RESULTS:
Forty-two patients were followed up for a median of 39 months (range, 25–90 mo; mean, 45.8 mo). The median maximum AVM diameter during the radiosurgery was 1.8 cm (range, 0.9–4.0 cm; mean, 2.07 cm), and the median AVM volume was 2.8 cm3 (range, 0.2–18.3 cm3; mean, 4.74 cm3). The mean marginal dose was 16.2 Gy (median, 15 Gy), and the median maximum dose was 22.4 Gy (range, 16.6–30 Gy). The AVM cure rate after the first radiosurgical treatment, using angiography- and magnetic resonance imaging-confirmed obliteration, was 61.9%. The predicted obliteration using the obliteration prediction index was 60%. Eight patients developed radiation-induced complications (19%). The deficit was transient in three patients (7.1%) and permanent in five patients (11.9%). The risk of postradiosurgical hemorrhage in this cohort was 9.5% for the first year, 4.7% for the second year, and 0% thereafter. Excellent outcome (obliteration plus no new deficit) was achieved in 70% of the patients in the group with radiosurgery-based AVM score less than 1.5 compared with 40.9% in the group with radiosurgery-based AVM score greater than 1.5% (P = 0.059).
CONCLUSION:
Radiosurgery for deep AVMs has a satisfactory obliteration rate and acceptable morbidity, considering the risk of hemorrhage without treatment and the risk of morbidity associated with other treatment modalities.
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Affiliation(s)
- Yuri M Andrade-Souza
- Division of Neurosurgery, Sunnybrook and Women's College, Health Science Centre,University of Toronto, Toronto, Ontario, Canada
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Tsao MN, Sultanem K, Chiu D, Copps F, Dixon P, Easton D, Haddad P, Hayter C, Hoegler D, Wong R. Supportive care management of brain metastases: what is known and what we need to know. Conference proceedings of the National Cancer Institute of Canada (NCIC) Workshop on Symptom Control in Radiation Oncology. Clin Oncol (R Coll Radiol) 2004; 15:429-34. [PMID: 14570093 DOI: 10.1016/s0936-6555(03)00220-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVES To review the results of published randomised controlled trials in the treatment of brain metastases and, from the knowledge gained from these trials, to identify potential study questions. MATERIALS AND METHODS The literature was searched for randomised controlled trials that dealt with the management of brain metastases. Potential research questions were identified on the basis of the results of the literature review. RESULTS A number of research questions were identified. In the context of the NCIC Symptom Control Group, a trial of supportive care alone vs supportive care and whole-brain radiotherapy (WBRT) in a subset of patients with the diagnosis of brain metastases was deemed to be of highest priority. We discussed a number of issues relating to the feasibility of such a trial. CONCLUSIONS The optimal management of brain metastases remains elusive. Despite the results of numerous randomised controlled trials, many questions remain unanswered. The magnitude of benefit using WBRT above supportive care alone is uncertain. A trial of supportive care alone vs supportive care and WBRT may be successful once target population, feasibility and methodological issues are thoroughly solved.
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Affiliation(s)
- M N Tsao
- Toronto-Sunnybrook Regional Cancer Centre, University of Toronto, Toronto, Canada.
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Tsao MN, Sneed PK, McDermott MW, Larson DA. Radiosurgery and radiotherapy for non-small-cell lung cancer metastatic to brain. Clin Lung Cancer 2004; 2:197-203. [PMID: 14700478 DOI: 10.3816/clc.2001.n.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Non-small-cell lung cancer metastatic to brain represents a common problem in oncology. Treatment modalities include stereotactic radiosurgery (SRS), whole-brain radiotherapy (WBRT), surgical resection, supportive care, or a combination of these options. This review outlines therapeutic strategies for treatment with particular attention to the use of SRS. Radiosurgical technique, radiobiology, dose prescription, patient selection, and results of therapy are discussed. The term SRS describes a radiation procedure that utilizes a three-dimensional stereotactic localization system to precisely treat small intracranial targets with a single, large, highly focal radiation dose. Stereotactic radiosurgery is appealing for several reasons; it is minimally invasive, easily tolerated, and highly effective, and patients return to normal baseline function within 24 hours. Stereotactic radiosurgery provides much higher control rates of treated lesions than does WBRT. Randomized trials are underway to ascertain the optimal role and timing of SRS in relation to WBRT in order to maximize control, survival, quality of life, and neuropsychological outcome.
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Affiliation(s)
- M N Tsao
- Department of Radiation Oncology, Toronto-Sunnybrook Regional Cancer Centre, The University of Toronto, Toronto, Ontario, Canada
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Abstract
BACKGROUND There is growing evidence that positive psychosocial intervention improves the wellbeing of cancer patients. Two meta-analyses conducted to date confirmed a significant small-to-moderate effect on quality of life. Previous randomized trials reported that psychosocial intervention also improved survival. However, more recent trials failed to detect a difference in survival. A systematic review of randomized trials that have examined the effectiveness of psychosocial intervention in cancer patients in terms of survival prolongation was conducted. METHODS Randomized trials published between 1966 and June 2002 were identified through the databases of MEDLINE, EMBASE, CancerLit, CINAHL, Cochrane Library and reference lists of relevant articles. Relevant data were abstracted. The results of randomized trials were pooled using meta-analyses to estimate the effect of treatment on overall survival at one and four years in all cancer patients and also in breast cancer patients with metastases. RESULTS Eight trials, which involved a total of 1062 patients (all cancer histologies), were identified. One- and four-year overall survival rates were obtained from eight trials and six trials, respectively. There was no statistically significant difference in the overall survival rates at one and four years [P = 0.6; RR 0.94 (95% CI 0.72, 1.22)] and [P = 0.5; RR 0.93 (95% CI 0.77, 1.13)], respectively. Four trials examined 511 metastatic breast cancer patients. Again, there was no statistically significant difference in the overall survival rates at one and four years [P = 0.3; RR 0.87 (95% CI 0.67, 1.14)] and [P = 0.3; RR 0.91 (95% CI 0.76, 1.10)], respectively. CONCLUSIONS Psychosocial intervention does not prolong survival in cancer. This meta-analysis can not rule out small effect sizes because of the small number of trials and small trial sizes.
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Affiliation(s)
- Edward Chow
- Department of Radiation Oncology, Toronto Sunnybrook Regional Cancer Centre, University of Toronto, Toronto, Ontario, Canada.
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Tsao MN, Schwartz ML, Bernstein M, Halliday WC, Lightstone AW, Hamilton MG, Jaywant S, Laperriere N. Capillary hemangioma of the cavernous sinus. Report of two cases. J Neurosurg 2003; 98:169-74. [PMID: 12546367 DOI: 10.3171/jns.2003.98.1.0169] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Capillary hemangiomas are rare benign vascular tumors that tend to occur in children. Whereas the majority of hemangiomas may regress spontaneously, those associated with functional sequelae or severe symptoms may require treatment. Two patients with capillary hemangiomas of the cavernous sinus that caused neurological symptoms were treated with fractionated stereotactic radiation therapy. Both hemangiomas had shown a progressive increase in size during observation before radiation therapy; both tumors regressed after radiotherapy. Up to the time of the last follow-up evaluation both patients experienced symptomatic relief after radiation. One patient's tumor remains in complete remission and the second tumor continues to demonstrate minor residual contrast enhancement without progression. The authors conclude that fractionated stereotactic radiation therapy is a useful treatment modality in the management of symptomatic capillary hemangiomas when these tumors arise in regions of the brain or skull base in which a complete resection cannot be accomplished.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Toronto-Sunnybrook Regional Cancer Centre, Ontario, Canada.
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Tsao MN, Chow E, Wong R, Rakovitch E, Laperriere N. Whole brain radiotherapy for the treatment of multiple brain metastases. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2002. [DOI: 10.1002/14651858.cd003869] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Tsao MN, Tsang RW, Liu FF, Panzarella T, Rotstein L. Radiotherapy management for squamous cell carcinoma of the nasal skin: the Princess Margaret Hospital experience. Int J Radiat Oncol Biol Phys 2002; 52:973-9. [PMID: 11958891 DOI: 10.1016/s0360-3016(01)02752-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To evaluate the outcome of radiotherapy (RT) for squamous cell carcinoma (SCC) of the nasal skin. MATERIALS AND METHODS The charts of 100 patients referred and treated with RT during 1982 to 1993 for SCC of nasal skin were reviewed. Most patients (81%) were treated with orthovoltage X-rays. In general, lesions </=2 cm were treated to 35 Gy in 5 fractions. For tumors 2-5 cm, 45 Gy in 10 fractions was commonly used. Lesions >5 cm or those associated with bone or cartilage invasion were typically treated to 50 Gy in 20 fractions. Six patients were lost to follow-up, leaving 94 patients assessable for local or regional failure analysis. Using the UICC staging system, the T stage at first presentation was as follows: T1, 60 patients; T2, 11 patients; T3, 0 patients, T4, 7 patients; TX, 16 patients. Only 1 patient had regional lymph node disease at presentation. Thirty-one patients were treated with surgery, followed by RT. Sixty-three patients were treated with primary RT. RESULTS The local relapse-free rate was 90% and 85% at 2 and 5 years, respectively. The actuarial 2 and 5-year overall survival rate was 75% and 51%, respectively. The cause-specific survival was 96% at both 2 and 5 years. No Radiation Therapy Oncology Group Grade 4 toxicities occurred. Univariate analysis could not identify any patient, tumor, or treatment factors that were statistically significant prognosticators. CONCLUSION RT for SCC of nasal skin achieves excellent outcome, is well tolerated, and should continue to be recommended in the management of this disease.
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Affiliation(s)
- May N Tsao
- Department of Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
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Tsao MN, Li YQ, Lu G, Xu Y, Wong CS. Upregulation of vascular endothelial growth factor is associated with radiation-induced blood-spinal cord barrier breakdown. J Neuropathol Exp Neurol 1999; 58:1051-60. [PMID: 10515228 DOI: 10.1097/00005072-199910000-00003] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The pathogenesis of radiation-induced injury to the central nervous system (CNS) remains unclear. Dysfunction of the blood-brain barrier (BBB) is associated with radiation-induced white matter lesions. The aim of this study was to determine if vascular endothelial growth factor (VEGF) is implicated in radiation-induced BBB disruption. Adult rats were irradiated with a single dose of 8 or 22 Gy to the spinal cord from C2 to T2. At various times up to 20 weeks following irradiation, blood-spinal cord barrier (BSCB) permeability was assessed using immunohistochemistry with anti-albumin antibody. Cell proliferation was assessed using bromodeoxyuridine (BrdU), and endothelial cell identity was assessed morphologically and using immunostaining for factor VIII-related antigen. Expression of VEGF protein and message was assessed using immunohistochemistry and in situ hybridization respectively. In the unirradiated rat spinal cord, there was no evidence of albumin immunoreactivity and little evidence of VEGF expression. After a dose of 22 Gy, focal albumin staining in white matter was observed at 16 weeks. Diffuse staining was seen at 20 weeks and was associated with necrosis and demyelination in white matter. This was associated with a significant increase in white matter glial cells that showed immunoreactivity and in situ hybridization signal for VEGE VEGF expressing cells showed dual immunoreactivity for glial fibrillary acidic protein. No increase in VEGF positive cells was observed in gray matter after 22 Gy. After a dose of 8 Gy, there was no increase in VEGF expression or albumin immunostaining in either white or gray matter. Microvessel endothelial cell density showed a trend towards a decrease with time after 22 Gy as compared with 8 Gy or unirradiated controls. BrdU immunostaining provided no evidence for endothelial cell proliferation in control or in the irradiated spinal cord. It is concluded that radiation-induced BSCB dysfunction is associated with upregulation of VEGF in astrocytes without associated endothelial proliferation. The temporal and spatial association of VEGF upregulation with the white matter lesions suggests a role of VEGF in radiation-induced late CNS injury.
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Affiliation(s)
- M N Tsao
- Department of Radiation Oncology, Ontario Cancer Institute/Princess Margaret Hospital, University of Toronto, Canada
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Abstract
The most common indication for the use of radiation therapy in the treatment of benign central nervous system disease is for the treatment of benign brain tumors, such as meningioma, pituitary adenoma, acoustic neuroma, arteriovenous malformation, and craniopharyngioma. Other less common benign intracranial tumors treated with radiation include chordoma, pilocytic astrocytoma, pineocytoma, choroid-plexus papilloma, hemangioblastoma, and temporal bone chemodectomas. Benign conditions, such as histiocytosis X, trigeminal neuralgia, and epilepsy, are also amenable to radiation treatment. There have also been reports of radiosurgery being used for the treatment of movement disorders and psychiatric disturbances, such as obsessive-compulsive and anxiety disorders. For benign brain tumors, radiation therapy as either primary or adjuvant therapy plays an integral role in improving local control. In the treatment of trigeminal neuralgia, epilepsy, tremor, and some psychiatric disturbances, radiosurgery may help ameliorate or eliminate some symptoms. Patients with benign central nervous system disease are expected to live a long time. As such, treatment should be highly conformal and based on three-dimensional planning using magnetic resonance imaging, computed tomography, or both. It is critical that damage to normal brain be minimized.
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Affiliation(s)
- M N Tsao
- Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94143, USA
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