SarCNU in Treating Patients With Recurrent Malignant Glioma

DISEASE CHARACTERISTICS: * Histologically confirmed malignant glioma * Anaplastic astrocytoma (AA) OR * Glioblastoma multiforme (GBM) * Recurrent or progressive disease by contrast-enhanced CT scan or MRI after primary surgery and radiotherapy * At least 1 bidimensionally measurable lesion * At least 1 cm by 1 cm on contrast-enhanced CT scan or MRI PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * ECOG 0-2 Life expectancy: * At least 12 weeks Hematopoietic: * Absolute granulocyte count at least 1,500/mm3 * Platelet count at least 120,000/mm3 Hepatic: * Bilirubin normal * AST and ALT no greater than 2.5 times upper limit of normal Renal: * Creatinine normal OR * Creatinine clearance at least 60 mL/min Cardiovascular: * No symptomatic congestive heart failure * No unstable angina pectoris * No cardiac arrhythmia Pulmonary: * DLCO at least 70% of predicted * FVC at least 70% of predicted Other: * No other malignancy within the past 5 years except adequately treated nonmelanoma skin cancer or curatively treated carcinoma in situ of the cervix * No ongoing or active uncontrolled infection * No other serious illness or medical condition that would preclude study * No history of significant neurologic or psychiatric disorder that would preclude study * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception during and for at least 3 months after study PRIOR CONCURRENT THERAPY: Biologic therapy: * At least 6 weeks since prior immunotherapy * No concurrent immunotherapy Chemotherapy: * At least 6 weeks since prior chemotherapy * No more than 1 prior adjuvant chemotherapy regimen for AA * No prior chemotherapy for recurrent disease * No other concurrent chemotherapy Endocrine therapy: * Patients must be on a stable dose of steroids for at least 2 weeks prior to study Radiotherapy: * See Disease Characteristics * At least 4 weeks since prior radiotherapy * No prior radiotherapy for recurrent disease * No concurrent radiotherapy Surgery: * See Disease Characteristics * Prior surgery for recurrent disease (e.g., stereotactic biopsy or partial resection) allowed * At least 4 weeks since prior surgery (except for biopsy) Other: * At least 6 weeks since prior investigational agents * No other concurrent investigational agents * No other concurrent anticancer treatment