DISEASE CHARACTERISTICS:

• Histologically confirmed ependymoma that is unlikely to respond to existing therapy and for which no curative therapy exists

  • Evidence of tumor by MRI or CT scan
• Tumor must be at least 5 mm
• No brain stem tumors

PATIENT CHARACTERISTICS:

Age:

• 6 months and over

Performance status:

• Karnofsky 60-100%

Life expectancy:

• At least 2 months

Hematopoietic:

• WBC at least 2,000/mm3
• Platelet count greater than 50,000/mm3

Hepatic:

• Bilirubin no greater than 2.5 mg/dL
• SGOT/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
• No history of renal conditions that contraindicate high dosages of sodium

Cardiovascular:

• No severe heart disease
• No uncontrolled hypertension
• No history of congestive heart failure
• No history of other cardiovascular conditions that contraindicate high dosages of sodium

Pulmonary:

• No severe lung disease

Other:

• Not pregnant or nursing
• Fertile patients must use effective contraception during and for 4 weeks after study
• No serious active infections or fever
• No other serious concurrent disease

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• At least 4 weeks since prior immunotherapy and recovered
• No concurrent immunomodulating agents

Chemotherapy:

• At least 4 weeks since prior chemotherapy and recovered (6 weeks for nitrosoureas)
• No concurrent antineoplastic agents

Endocrine therapy:

• Concurrent corticosteroids for cerebral edema allowed (must be on stable dose for at least 1 week prior to study)

Radiotherapy:

• At least 8 weeks since prior radiotherapy and recovered

Surgery:

• Not specified

Other:

• No prior antineoplaston therapy