PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 90-100% Life expectancy: Greater than 6 months Hematopoietic: WBC at least 3,000/mm3 Absolute neutrophil count at least 1,500/mm3 Hemoglobin at least 8.0 g/dL Platelet count at least 75,000/mm3 Hepatic: Liver function tests no greater than 2.5 times upper limit of normal (ULN) Renal: Creatinine no greater than 1.5 times ULN Cardiovascular: No New York Heart Association class III or IV heart disease with uncontrolled and/or unstable cardiac or coronary artery disease Other: No other malignancy within the past 5 years that would confound the etiology of metastatic disease except curatively treated nonmelanomatous skin cancer No other nonmalignant disease that would confound evaluation or preclude compliance Fertile patients must use effective contraception