PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: Greater than 2 months Hematopoietic: Absolute neutrophil count 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.5 mg/dL Transaminases no greater than 4 times upper limit of normal Renal: Creatinine no greater than 1.7 mg/dL Cardiovascular: No uncontrolled hypertension No angina pectoris No evidence of uncontrolled cardiac dysrhythmia Other: No serious infection or other medical illness No other prior or concurrent malignancy within 5 years except curatively treated basal or squamous cell carcinoma of the skin or carcinoma in situ of the cervix and breast Not pregnant or nursing Adequate contraception required of all fertile patients