PATIENT CHARACTERISTICS: Age: 16 and over Performance status: Karnofsky 60-100% Life expectancy: Greater than 8 weeks Hematopoietic: Absolute granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: SGPT less than 2 times institutional normal Alkaline phosphatase less than 2 times institutional normal Bilirubin less than 1.5 mg/dL Renal: BUN less than 1.5 times institutional normal OR Creatinine less than 1.5 times institutional normal Other: No active infection Not pregnant or nursing Fertile patients must use effective contraception 1 month before, during, and 1 month after study No other disease that will obscure toxicity or alter drug metabolism No other concurrent medical illness