Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically confirmed anaplastic astrocytoma or anaplastic
oligoastrocytoma in first relapse Recurrence or progression at least 6 months from initial
diagnosis Must have received maximally feasible surgical resection and fractionated
external beam radiotherapy Must have received no more than 1 prior systemic cytotoxic
chemotherapy regimen for initial disease Bidimensionally measurable disease by MRI scan
(stable dose of corticosteroids for at least 7 days prior to scan)

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 75,000/mm3 Hemoglobin at least 9 g/dL Hepatic: AST no greater than
3 times upper limit of normal (ULN) Bilirubin less than 1.5 times ULN Renal: Creatinine no
greater than 2 mg/dL OR Creatinine clearance at least 40 mL/min Other: Not pregnant or
nursing Negative pregnancy test Fertile patients must use effective contraception during
and for 3 months after the study No known allergy to etoposide No other acute or chronic
medical illness or psychiatric disorder

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior epoetin alfa,
filgrastim (G-CSF), or sargramostim (GM-CSF) and recovered No concurrent immunotherapy
Chemotherapy: See Disease Characteristics At least 4 weeks since prior chemotherapy (2
weeks since vincristine; 6 weeks since nitrosoureas or mitomycin) and recovered No prior
leflunomide (SU101) therapy No other concurrent chemotherapy Endocrine therapy: No
concurrent hormonal therapy (except medroxyprogesterone acetate for appetite stimulation)
Radiotherapy: See Disease Characteristics No more than 1 prior course of radiotherapy At
least 8 weeks since prior radiotherapy and recovered No prior interstitial radiotherapy or
implanted carmustine wafers Prior radiosensitizer(s) concurrent with radiotherapy or used
as neoadjuvant therapy allowed No concurrent radiotherapy Surgery: See Disease
Characteristics No more than 2 prior surgical resections At least 1 week since prior
surgery or biopsy for anaplastic astrocytoma No concurrent surgery (including resection,
stereotactic surgery, or interstitial implants) Other: At least 4 weeks since prior
investigational agents No other concurrent investigational agents