RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die.

PURPOSE: Phase II trial to study the effectiveness of temozolomide in treating patients who have recurrent malignant glioma.

OBJECTIVES: I. Determine the safety and efficacy of temozolomide in patients with recurrent malignant glioma. II. Determine the radiographic response to this regimen in these patients. III. Determine the time to tumor progression of these patients on this regimen. IV. Determine the quality of life of these patients.

OUTLINE: Patients receive oral temozolomide once daily for 42 days. Courses repeat every 70 days for up to 1 year in the absence of disease progression or unacceptable toxicity. Quality of life is assessed every 1-2 months. Patients are followed every 3-4 months.

PROJECTED ACCRUAL: A total of 20-35 patients will be accrued for this study within 2 years.

DISEASE CHARACTERISTICS: Histologically confirmed recurrent malignant glioma, including: Glioblastoma Gliosarcoma High grade glioma Anaplastic astrocytoma Anaplastic mixed oligoastrocytoma Anaplastic oligodendroglioma Must have evidence of tumor recurrence or progression on gadolinium enhanced MRI or CT scan following radiotherapy with or without chemotherapy

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: Not specified Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hemoglobin at least 10 g/dL Hepatic: Bilirubin less than 1.5 times upper limit of normal (ULN) SGOT and SGPT less than 3 times ULN Alkaline phosphatase less than 2 times ULN Renal: Creatinine less than 1.5 times ULN BUN less than 1.5 times ULN Other: No nonmalignant systemic disease that would cause patient to be a poor medical risk No acute infection requiring intravenous antibiotics No psychological disorder that would interfere with study compliance HIV negative No AIDS-related illness Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception No frequent vomiting or medical condition that would interfere with oral medication intake (e.g., partial bowel obstruction) No prior or concurrent malignancy, except: Surgically cured carcinoma in situ of the cervix Basal or squamous cell skin cancer

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior immunotherapy At least 4 weeks since prior biologic therapy Chemotherapy: See Disease Characteristics At least 4 weeks since prior chemotherapy No prior temozolomide or dacarbazine Endocrine therapy: Not specified Radiotherapy: See Disease Characteristics At least 4 weeks since prior external beam radiotherapy At least 8 weeks since prior stereotactic radiosurgery Surgery: At least 2 weeks since prior brain biopsy, craniotomy, or other surgery