PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 OR Karnofsky 60-100% Life expectancy: Not specified Hematopoietic: Hemoglobin at least 10 g/dL WBC at least 4,000/mm3 Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than upper limit of normal (ULN) ALT/AST no greater than 2.5 times ULN Renal: Creatinine no greater than 1.5 mg/dL OR Creatinine clearance at least 50 mL/min Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception