Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed supratentorial pure or mixed anaplastic
oligodendroglioma

- Unifocal or multifocal disease

- Prior suspected or proven low-grade glioma eligible provided biopsy reveals pure
or mixed anaplastic oligodendroglioma that has not been previously treated with
radiotherapy and/or chemotherapy

- No equivocal oligodendroglial element

- No tumors predominantly located in the posterior fossa (i.e., brainstem or
cerebellum)

- No spinal cord tumors

- No evidence of spinal drop metastasis or spread to noncontiguous meninges

PATIENT CHARACTERISTICS:

Age:

- 18 to 65

Performance status:

- Zubrod 0-1

Life expectancy:

- More than 12 weeks

Hematopoietic:

- Absolute granulocyte count at least 1,500/mm^3

- Platelet count at least 100,000/mm^3

- Hemoglobin at least 10 g/dL

Hepatic:

- Bilirubin no greater than 2 times normal

- AST no greater than 3 times normal

- Alkaline phosphatase no greater than 2 times normal

Renal:

- Creatinine no greater than 1.5 times normal

Other:

- No active infection

- No other medical problems that would preclude study participation

- No other malignancy within the past 3 years except carcinoma in situ of the cervix or
nonmelanoma skin cancer

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- Not specified

Chemotherapy:

- See Disease Characteristics

- No prior chemotherapy for this malignancy

- No prior temozolomide

Endocrine therapy:

- Not specified

Radiotherapy:

- See Disease Characteristics

- No prior radiotherapy to the brain, head, or neck

Surgery:

- At least 14 days since prior surgery requiring general anesthesia