PATIENT CHARACTERISTICS: Age: Adult Performance status: SWOG 0-2 Hematopoietic: WBC (white blood cell) at least 3,500/mm3 Platelet count at least within the lower limit of normal Hepatic: Bilirubin no greater than 2 times upper limit of normal (ULN) AST (angiotensin sensitivity test) no greater than 2 times ULN Alkaline phosphatase no greater than 2 times ULN Renal: Creatinine no greater than 2 times ULN Other: No organic brain syndrome, Alzheimer's disease, or other altered mental status No second malignancy within 5 years except: Adequately treated nonmelanomatous skin cancer Adequately treated carcinoma in situ of the cervix Not pregnant or nursing Negative pregnancy test Effective contraception required of fertile patients