PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60%-100% Hematopoietic: WBC at least 3,500 Platelets greater than 150,000 Hepatic: Bilirubin less than 2.0 mg/dL Renal: Creatinine less than 1.5 mg/dL OR Creatinine clearance greater than 60 mL/min per 1.73 square meters Cardiovascular: No NYHA class III/IV status Other: No concomitant malignancy other than basal cell skin carcinoma Negative pregnancy test required of fertile women Adequate contraception required of fertile women