PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent colony stimulating factors during first course of study Chemotherapy: No more than 3 prior regimens of chemotherapy At least 6 weeks since prior platinum chemotherapy At least 4 weeks since other prior chemotherapy Endocrine therapy: Not specified Radiotherapy: No prior radiotherapy to more than 30% of bone marrow Surgery: At least 10 days since placement of biliary shunt Other: No other concurrent investigational agents No concurrent antiretroviral therapy (HAART) in HIV positive patients