PATIENT CHARACTERISTICS: Age: Over 18 Performance status: ECOG 0-1 Life expectancy: At least 12 weeks Hematopoietic: Granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3 No inherited predisposition to hypercoagulation Hepatic: Bilirubin normal SGOT no greater than 2.5 times upper limit of normal Renal: Creatinine no greater than 1.5 mg/dL Cardiovascular: No uncompensated coronary artery disease on electrocardiogram or physical examination No myocardial infarction or severe unstable angina within the past 6 months No severe peripheral vascular disease related to diabetes mellitus No deep venous or arterial thrombosis within the past 3 months No inherited predisposition to thrombosis Pulmonary: No pulmonary embolism within the past 3 months Other: No other malignancies within the past 5 years except basal or squamous cell skin cancer or carcinoma in situ of the cervix No other significant medical illness No serious active infections Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception