RATIONALE: Antineoplastons are naturally-occurring substances that may also be made in the laboratory. Antineoplastons may inhibit the growth of cancer cells.

PURPOSE: This phase II trial is studying how well antineoplaston therapy works in treating children with primitive neuroectodermal tumors that has not responded to standard therapy.

OBJECTIVES:

• Demonstrate the antitumor activity of antineoplastons A10 and AS2-1 in children with primitive neuroectodermal tumors by determining the proportion of patients who experience an objective tumor response.
• Evaluate the adverse effects of and tolerance to this regimen in these patients.

OUTLINE: This is an open-label study.

Patients receive gradually escalating doses of intravenous antineoplaston A10 and antineoplaston AS2-1 6 times a day until the maximum tolerated dose is reached. Treatment continues for at least 2 months in the absence of disease progression or unacceptable toxicity. After 2 months, patients with responding or stable disease may continue treatment.

Tumors are measured every 8 weeks for 2 years, every 3 months for the third and fourth years, every 6 months for the fifth and sixth years, and then annually thereafter.

PROJECTED ACCRUAL: A total of 20-40 patients will be accrued for this study.

• Drug: antineoplaston A10
• Drug: antineoplaston AS2-1

DISEASE CHARACTERISTICS:

• Histologically confirmed (except if medically contraindicated) incurable primitive neuroectodermal tumor

  • Evidence of progressive or recurrent tumor by MRI or CT scan performed within 2 weeks prior to study entry
• Must have received and failed prior standard therapy
• 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 at least 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 insufficiency

Renal:

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

Cardiovascular:

• No uncontrolled hypertension
• No severe heart disease
• No history of congestive heart failure
• No 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 participation
• No serious active infections or fever
• No other serious concomitant 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 (6 weeks for nitrosoureas) and recovered
• No concurrent antineoplastic agents

Endocrine therapy:

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

Radiotherapy:

• At least 8 weeks since prior radiotherapy and recovered

Surgery:

• Not specified

Other:

• No prior antineoplaston treatment