DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed anaplastic astrocytoma

  • Tumor subtotally resected or biopsied
• Radiologic evidence of residual or recurrent tumor by gadolinium-enhanced MRI, CT scan, or positron-emission tomography
• No brain stem tumors

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• Karnofsky 60-100%

Life expectancy:

• More than 2 months

Hematopoietic:

• WBC at least 1,500/mm^3
• Platelet count at least 50,000/mm^3
• Hemoglobin at least 10 g/dL

Hepatic:

• Bilirubin no greater than 2.5 mg/dL
• SGOT and SGPT no greater than 5 times upper limit of normal
• No hepatic failure

Renal:

• Creatinine no greater than 2.5 mg/dL
• No renal failure

Cardiovascular:

• No prior congestive heart failure
• No coronary artery disease
• No myocardial infarction within the past year
• No angina requiring medication
• No uncontrolled hypertension

Pulmonary:

• No moderate to severe chronic obstructive pulmonary disease

Other:

• Not pregnant or nursing
• Fertile patients must use effective contraception during and for 4 weeks after study participation
• No active infection
• No other concurrent serious disease
• No other prior malignancy except carcinoma in situ of the cervix or superficial nonmelanoma skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior immunotherapy
• No concurrent immunomodulating agents

Chemotherapy:

• No prior myelosuppressive chemotherapy

Endocrine therapy:

• Concurrent corticosteroids for cerebral edema allowed

Radiotherapy:

• No prior myelosuppressive radiotherapy
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics
• Recovered from any prior surgery

Other:

• No prior cytodifferentiating agents
• No prior antineoplaston therapy
• No other concurrent antineoplastic agents