PATIENT CHARACTERISTICS: Age: 18-69 Performance status: WHO 0-2 Life expectancy: At least 3 months Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.25 times upper limit of normal (ULN) Alkaline phosphatase no greater than 2 times ULN AST/ALT no greater than 2 times ULN Renal: Creatinine no greater than 1.25 times ULN Creatinine clearance at least 60 mL/min Other: Not pregnant or lactating Effective contraception required of fertile women No diseases interfering with follow-up