PATIENT CHARACTERISTICS: Age: 18 and over Performance status: WHO 0-2 Life expectancy: At least 4 months Hematopoietic: WBC at least 4,000/mm3 Platelet count at least 100,000/mm3 Hemoglobin at least 10 g/dL Hepatic: Bilirubin less than 1.17 mg/dL ALT or AST less than 2 times upper limit of normal (ULN) Alkaline phosphatase less than 2 times ULN (unless due to liver or bone metastases) Renal: Creatinine less than 1.5 mg/dL Cardiovascular: No ischemic heart disease Other: Not pregnant or nursing Fertile patients must use effective contraception at least 4 weeks before, during, and for 4 weeks after the study No other serious medical condition or serious infection within past 28 days No other active concurrent malignancies, except: Carcinoma in situ of the cervix Adequately treated basal or squamous cell carcinoma of the skin No autoimmune disorders No inflammatory bowel disease No diabetes