PATIENT CHARACTERISTICS: Age: 18 and over Performance status: SWOG 0-2 Life expectancy: Not specified Hematopoietic: WBC greater than 4000/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 2 times upper limit of normal (ULN) SGOT no greater than 2 times ULN Renal: Creatinine no greater than 2 times ULN Other: Not pregnant or nursing Fertile patients must use effective contraception