PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-3 Life expectancy: At least 12 weeks Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin normal AST no greater than 3 times normal (5 times normal with liver involvement) Renal: Creatinine no greater than 2.0 mg/dL Cardiovascular: No uncontrolled hypertension No unstable angina No active congestive heart failure No myocardial infarction within 6 months No serious uncontrolled arrhythmia Other: No active or uncontrolled infection No HIV antibody No medical or psychiatric condition that precludes participation No malignancy in the past 5 years, except carcinoma in situ of the cervix, resected basal cell or squamous cell carcinomas of the skin, or prostate cancer that is in remission following a radical retropubic prostatectomy or radiation therapy No pregnant or nursing women Negative pregnancy test required of fertile women within 7 days prior to entry Effective contraception required of fertile patients throughout study and at least 30 days thereafter