PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Life expectancy: Greater than 12 weeks Hematopoietic: WBC at least 4,000/mm3 Granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.2 mg/dL SGOT less than 4 times upper limit of normal Renal: Creatinine no greater than 1.5 mg/dL or Creatinine clearance at least 60 mL/min Other: No history of any other malignancy except curatively treated nonmelanoma skin cancer and carcinoma in situ of the cervix No active infection or other serious medical conditions deemed unacceptable Negative pregnancy test Effective contraception required of all fertile patients