Brachytherapy in Treating Patients With Recurrent Malignant Glioma

DISEASE CHARACTERISTICS: Histologically confirmed malignant glioma Anaplastic astrocytoma, anaplastic oligodendroglioma, or glioblastoma multiforme Low-grade astrocytoma that progresses to high-grade astrocytoma allowed Unifocal disease Progressive or recurrent after radiotherapy with or without chemotherapy Previously treated with at least 5,000 cGy external beam radiotherapy more than 3 months ago Candidate for maximal surgical resection Any expected residual enhancing tumor must be within expected brachytherapy treatment volume Resection must not be expected to result in a new permanent neurologic deficit No tumor crossing more than 1 cm beyond the midline on preoperative MRI or CT scan No grossly or radiographically apparent leptomeningeal spread No ventricular invasion outside the anticipated radiotherapy treatment volume No marked edema on MRI or CT scan Patients with 2 or more separate foci of contrast-enhancing tumors that are more than 5 cm apart on preoperative MRI or CT scan are ineligible PATIENT CHARACTERISTICS: Age 18 and over Performance status Karnofsky 60-100% Life expectancy Not specified Hematopoietic Absolute neutrophil count at least 1,500/mm^3 Platelet count at least 100,000/mm^3 Hepatic Not specified Renal Creatinine no greater than 1.7 mg/dL BUN no greater than 2 times upper limit of normal Cardiovascular No uncontrolled hypertension No unstable angina pectoris No uncontrolled cardiac dysrhythmia Other Mini mental score at least 15 No other medical illness that would preclude study participation No serious infection No other malignancy within the past 5 years except curatively treated carcinoma in situ of the cervix or nonmelanoma skin cancer Not pregnant or nursing Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy No concurrent immunotherapy No concurrent biologic agents (e.g., immunotoxins, immunoconjugates, antiangiogenesis compounds, antisense therapy, peptide receptor antagonists, interferons, interleukins, tumor-infiltrating lymphocytes, lymphokine-activated killer cells, or gene therapy) Chemotherapy See Disease Characteristics At least 3 weeks since prior chemotherapy (6 weeks for nitrosoureas) No concurrent polifeprosan 20 with carmustine implant (Gliadel wafer) Endocrine therapy Concurrent corticosteroids allowed to improve quality of life Radiotherapy See Disease Characteristics No concurrent radiosurgery Surgery See Disease Characteristics See Radiotherapy Other Recovered from prior therapy No prior investigational agents No investigational agents during and for 90 days after study participation Concurrent cytotoxic treatment allowed to improve quality of life