PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Life expectancy: At least 12 weeks Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.5 times upper limit of normal (ULN) ALT and AST no greater than 2.0 times ULN Renal: Creatinine no greater than 1.5 times ULN Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for 3 months after study No concurrent systemic disorder that would preclude study No active infection