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 with recurrent oligodendroglial tumors.

OBJECTIVES: I. Assess the therapeutic activity of temozolomide as first line chemotherapy in patients with recurrent oligodendroglial tumors after radiation therapy. II. Assess the objective response and duration of response of these patients given this treatment. III. Characterize the acute side effects of temozolomide in this patient population.

OUTLINE: This is an open label, multicenter study. Patients receive oral temozolomide on days 1-5. Courses are repeated every 28 days. Treatment continues for a maximum of 12 courses in the absence of unacceptable toxicity or disease progression. Patients are followed every 3 months until disease progression.

PROJECTED ACCRUAL: A total of 15-33 patients will be accrued for this study.

DISEASE CHARACTERISTICS: Histologically proven oligodendroglioma or oligoastrocytoma with at least 25% oligodendroglial elements Recurrent or progressive disease following radiotherapy At least 3 months since prior radiotherapy Measurable disease by MRI or CT scan Lesion must have a diameter of at least 1 cm No progressive neurological deficits from the present recurrence No new neurological deficits interfering with daily activities No tumor causing midline shift or brain stem compression due to which a rapid deterioration is to be expected in case of no response No signs of increased intracranial pressure No extracranial disease

PATIENT CHARACTERISTICS: Age: 18 to 70 Performance status: WHO 0-2 Life expectancy: At least 3 months Hematopoietic: Neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.25 times upper limit of normal (ULN) AST/ALT no greater than 2 times ULN Alkaline phosphatase no greater than 2 times ULN Renal: Creatinine clearance at least 60 mL/min Creatinine no greater than 1.25 times ULN Neurologic: See Disease Characteristics Other: Not pregnant or nursing Fertile patients must use effective contraception No other malignant or nonmalignant diseases interfering with follow-up No psychological, familial, sociological, or geographical condition potentially hampering compliance with the study and follow-up

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior chemotherapy Endocrine therapy: Not specified Radiotherapy: See Disease Characteristics Surgery: Not specified Other: No other concurrent investigational drugs No other concurrent antitumor agents