PATIENT CHARACTERISTICS: Age: 1 to 21 Performance status: Not specified Hematopoietic: (unless bone marrow involvement by tumor) Absolute neutrophil count greater than 1,000/mm3 Platelet count greater than 100,000/mm3 Hepatic: Bilirubin less than 3.0 mg/dL Renal: Creatinine less than 1.5 mg/dL Creatinine clearance or radionuclide GFR greater than 60 mL/min Cardiovascular: EKG normal Ejection fraction at least 55% by radionuclide MUGA OR Fractional shortening at least 28% by echocardiogram Other: No other significant organ dysfunction that precludes study treatment Body weight at least 10 kg Not pregnant or nursing Effective contraception required of fertile patients