PATIENT CHARACTERISTICS: Age: 18 and over Performance status: CTC 0-2 Life expectancy: Not specified Hematopoietic: Granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: SGOT less than 2 times upper limit of normal Bilirubin less than 1.5 mg/dL Renal: Not specified Other: Not pregnant or nursing Fertile patients must use effective contraception