PATIENT CHARACTERISTICS: Age: 50 and under (patients aged 51-55 accrued on a case-by-case basis after discussion and approval by the BMT service) Performance status: Karnofsky 70-100% Life expectancy: Greater than 8 weeks Hematopoietic: Not specified Hepatic: Bilirubin less than 1.5 mg/dL AST no greater than 3 times normal Neither value increasing for at least 2-4 weeks prior to transplant Renal: Creatinine less than 2 times normal and not rising for at least 2-4 weeks prior to transplant OR Creatinine clearance greater than 80 mL/min Cardiovascular: Left ventricular ejection fraction at least 50% Cardiac function good Pulmonary: No severe restrictive lung disease No chronic obstructive pulmonary disease Other: No active viral or bacterial infection at transplant No coexisting medical problem that would significantly increase the risk of the transplant procedure Not pregnant