PATIENT CHARACTERISTICS: Age: 16 and over (no prepubertal patients) Performance status: 0-2 Life expectancy: More than 2 months Hematopoietic: Absolute granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 2 mg/dL Transaminases no greater than 3 times upper limit of normal (ULN) Alkaline phosphatase no greater than 3 times ULN Renal: Not specified Cardiovascular: No history of deep vein thrombosis Other: Not pregnant Fertile patients must use effective barrier contraception