Antineoplaston Therapy in Treating Patients With Ependymoma

DISEASE CHARACTERISTICS: Histologically confirmed ependymoma that is unlikely to respond to existing therapy and for which no curative therapy exists Evidence of residual tumor (>= 5mm) by MRI scan performed within two weeks prior to study entry 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