Antineoplaston Therapy in Treating Children With Brain Tumors

DISEASE CHARACTERISTICS: Histologically confirmed (except if medically contraindicated) childhood brain tumor for which no curative therapy exists Measurable tumor by MRI scan performed within two weeks prior to study entry Tumor must be at least 5 mm PATIENT CHARACTERISTICS: Age: 6 months to 17 years Performance status: Karnofsky 60-100% Life expectancy: At least 2 months Hematopoietic: WBC greater than 2000/mm^3 Platelet count greater than 50,000/mm^3 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 history of renal conditions that contraindicate high dosages of sodium Cardiovascular: No severe heart disease No history of heart failure No history of other cardiovascular conditions that contraindicate high dosages of sodium No uncontrolled hypertension Pulmonary: No severe lung disease Other: Not pregnant or nursing Fertile patients must use effective contraception during and for 4 weeks after study participation No serious active infections or fever No other serious concurrent disease PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior immunotherapy No concurrent immunomodulating agents Chemotherapy: At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas) and recovered No concurrent antineoplastic agents Endocrine therapy: Concurrent corticosteroids for cerebral edema allowed (must be on stable dose for at least 1 week before study entry) Radiation therapy: At least 8 weeks since prior radiotherapy and recovered Surgery: Recovered from any prior surgery Other: No prior antineoplaston therapy