PATIENT CHARACTERISTICS: Age: Over 18 Performance status: ECOG 0-3 Hematopoietic: WBC at least 3,000/mm3 Platelet count at least 75,000/mm3 Hepatic: Bilirubin no more than 2.0 mg/dL Transaminases no more than 2 x normal Alkaline phosphatase no more than 2 x normal Renal: Creatinine no more than 2.0 mg/dL Other: No active systemic infection No significant organ failure uncontrolled with medication No pregnant or lactating women Effective contraception required of fertile women