Radiation Therapy in Treating Patients With Progressive or Recurrent Malignant Brain Tumors

DISEASE CHARACTERISTICS: Histologically confirmed malignant glioma: Anaplastic astrocytoma Anaplastic oligodendroglioma Glioblastoma multiforme Unifocal disease Progressive or recurrent disease following radiation therapy and/or chemotherapy Must be eligible for surgical resection of the tumor mass No unresectable leptomeningeal spread or ventricular invasion outside the radiation treatment volume No exophytic ventricular tumors Must have a maximal cross-sectional diameter enhancing tumor greater than 2.0 cm but not greater than 5.0 cm by preoperative MRI Ratio of major axes of the tumor should not exceed 1.5 No marked edema by preoperative MRI or CT that cannot be corrected by tumor resection PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: Greater than 3 months Hematopoietic: Not specified Hepatic: Not specified Renal: Not specified Cardiovascular: No uncontrolled hypertension, angina pectoris, or uncontrolled cardiac dysrhythmia Other: Not pregnant or nursing Fertile patients must use effective contraception No serious concurrent infection or other medical illness No prior or concurrent malignancy within 5 years except for curatively treated carcinoma in situ of the cervix or basal cell carcinoma of the skin PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent biologic therapy Chemotherapy: See Disease Characteristics No concurrent chemotherapy At least 4 weeks since prior chemotherapy (6 weeks since nitrosoureas) and recovered Endocrine therapy: Not specified Radiotherapy: See Disease Characteristics At least 3 months since prior radiotherapy and recovered Surgery: See Disease Characteristics Other: At least 4 weeks since prior use of medical device No concurrent investigational agents