Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed recurrent glioblastoma
multiforme Measurable disease on contrast MRI Lesion at least 2 cm in diameter

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Karnofsky 70-100%
Life expectancy: At least 3 months Hematopoietic: WBC greater than 3,000/mm3 Platelet
count greater than 100,000/mm3 Hepatic: Bilirubin less than 1.5 times upper limit of
normal (ULN) Alkaline phosphatase no greater than 2 times ULN Transaminases no greater
than 2 times ULN Renal: Creatinine no greater than 1.5 mg/dL Cardiovascular: Normal
cardiac function No ischemic heart disease within the past 6 months Normal
electrocardiogram Other: No unstable systemic diseases No active uncontrolled infections
No prior or other concurrent malignancies except adequately treated basal or squamous cell
skin cancer or carcinoma in situ of the cervix No psychological, familial, sociological,
or geographical condition that would preclude study Not pregnant or nursing Fertile
patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: At least 6 weeks
since prior adjuvant chemotherapy for brain tumor No other prior chemotherapy Endocrine
therapy: Must be on stable or decreasing doses of corticosteroids for at least 2 weeks
Radiotherapy: At least 3 months since prior radiotherapy to the brain No prior high dose
radiotherapy No prior stereotactic boost or implant radiotherapy Surgery: No prior surgery
(except biopsy) for recurrent brain tumor At least 3 months since prior surgery for
primary brain tumor Other: No other concurrent anticancer agents No other concurrent
investigational therapy