Haroon Ahmad1, David Martin2, Sohil H Patel3, Joseph Donahue3, Beatriz Lopes4, Benjamin Purow1, David Schiff1, Camilo E Fadul5. 1. Department of Neurology, Division of Neuro-Oncology, University of Virginia Health System, P.O. Box 800432, Charlottesville, VA, 22908, USA. 2. Claude Moore Health Sciences Library, University of Virginia Health System, Charlottesville, VA, USA. 3. Department of Radiology and Medical Imaging, Division of Neuroradiology, University of Virginia Health System, Charlottesville, VA, USA. 4. Department of Pathology, Divisions of Neuropathology, University of Virginia Health System, Charlottesville, VA, USA. 5. Department of Neurology, Division of Neuro-Oncology, University of Virginia Health System, P.O. Box 800432, Charlottesville, VA, 22908, USA. CEF3W@hscmail.mcc.virginia.edu.
Abstract
BACKGROUND: Radiation therapy (RT) remains a mainstay for the treatment of lower grade gliomas. Radiation neurotoxicity is a serious complication, carrying high morbidity in the absence of tumor progression. The incidence remains poorly categorized and known risk factors identified are related to the radiation modality. We hypothesized that patients with oligodendroglioma have a higher risk of radiation necrosis (RN) as compared to patients with astrocytoma. METHODS: We conducted a retrospective review of adults with lower grade diffuse gliomas over a 10-year span. The primary outcome was RN, either pathologically confirmed or clinically diagnosed. Cases without pathological confirmation must have been symptomatic, requiring administration of bevacizumab or high-dose steroids. Cox proportional hazard ratios were used for multivariate analyses. RESULTS: In 319 patients, we identified RN in 41 patients (12.9%): 28 patients (21.3%) with oligodendroglioma and 13 (6.9%) with astrocytoma (HR 3.42, p < 0.001). Patients with oligodendroglioma who received > 54 Gy had a higher incidence (31.2%) than those receiving ≤ 54 Gy (14.3%, HR 6.9, p = 0.002). There was no similar correlation among patients with astrocytoma. There was no difference in incidence based on use of concomitant temozolomide. Radiation necrosis appeared within 24 months from radiation in 80.5% of patients. CONCLUSION: Our study suggests that patients with oligodendroglioma are at higher risk of developing RN. The incidence increases with increasing radiation dose in patients with oligodendroglioma but not with astrocytoma. RN usually appears within 24 months from RT. Patients with oligodendroglioma receiving > 54 Gy are at highest risk.
BACKGROUND: Radiation therapy (RT) remains a mainstay for the treatment of lower grade gliomas. Radiation neurotoxicity is a serious complication, carrying high morbidity in the absence of tumor progression. The incidence remains poorly categorized and known risk factors identified are related to the radiation modality. We hypothesized that patients with oligodendroglioma have a higher risk of radiation necrosis (RN) as compared to patients with astrocytoma. METHODS: We conducted a retrospective review of adults with lower grade diffuse gliomas over a 10-year span. The primary outcome was RN, either pathologically confirmed or clinically diagnosed. Cases without pathological confirmation must have been symptomatic, requiring administration of bevacizumab or high-dose steroids. Cox proportional hazard ratios were used for multivariate analyses. RESULTS: In 319 patients, we identified RN in 41 patients (12.9%): 28 patients (21.3%) with oligodendroglioma and 13 (6.9%) with astrocytoma (HR 3.42, p < 0.001). Patients with oligodendroglioma who received > 54 Gy had a higher incidence (31.2%) than those receiving ≤ 54 Gy (14.3%, HR 6.9, p = 0.002). There was no similar correlation among patients with astrocytoma. There was no difference in incidence based on use of concomitant temozolomide. Radiation necrosis appeared within 24 months from radiation in 80.5% of patients. CONCLUSION: Our study suggests that patients with oligodendroglioma are at higher risk of developing RN. The incidence increases with increasing radiation dose in patients with oligodendroglioma but not with astrocytoma. RN usually appears within 24 months from RT. Patients with oligodendroglioma receiving > 54 Gy are at highest risk.
Authors: M J van den Bent; D Afra; O de Witte; M Ben Hassel; S Schraub; K Hoang-Xuan; P-O Malmström; L Collette; M Piérart; R Mirimanoff; A B M F Karim Journal: Lancet Date: 2005 Sep 17-23 Impact factor: 79.321
Authors: Jeremy D Ruben; Michael Dally; Michael Bailey; Robin Smith; Catriona A McLean; Pasqual Fedele Journal: Int J Radiat Oncol Biol Phys Date: 2006-03-06 Impact factor: 7.038