NO-56. NEW TREATMENT FOR RADIATION NECROSIS OF THE BRAIN

Abstract

INTRODUCTION: Recently, higher dose radiation therapies have been developed and have contributed to the extension of survival time in patients with malignant brain tumors. Hence, there is an increase in opportunities to encounter radiation necrosis in clinical settings. We report on bevacizumab treatment for radiation necrosis as a new treatment modality. METHODS: Eight patients with radiation necrosis of the brain were treated with bevacizumab. Primary brain tumors were metastatic brain tumors in 4 patients, glioblastoma in 2 patients, anaplastic ependymoma in 1 patient, and anaplastic meningioma in 1 patient. Radiation necrosis was diagnosed by magnetic resonance (MR) images and boronophenylalanine positron-emission tomography. The treatment protocol was to administer bevacizumab intravenously biweekly, 6 cycles in total. Posttreatment MR images were obtained after 6 cycles of bevacizumab. RESULTS: Bevacizumab treatment was completed in 6 patients. Two patients were discontinued once and twice bevacizumab treatment because of asymptomatic intracerebral hematoma and cardiopulmonary arrest, respectively. Perifocal edema was decreased after bevacizumab treatment in all 6 patients. Of 6 patients, 4 patients improved their Karnofsky Performance Status. In these cases, a reduction of perifocal edema was 40% to 80%. CONCLUSIONS: Bevacizumab could be an effective treatment for radiation necrosis because vascular endothelial growth factor plays an important role in the process of radiation necrosis.