 - Adequate hematologic, hepatic and renal function determined by the following tests, within 4 weeks prior to randomization: white blood cell WBC 4000mm3 and platelets 100,000mm3; bilirubin upper limit of normal; serum glutamic pyruvate transaminase SGPT or alanine transaminase ALT and serum glutamic oxaloacetic transaminase SGOT or aspartate transaminase AST 2.5 x upper limit of normal if no demonstrable liver metastases or 5 times upper limit of normal in the presence of liver metastases; Calculated creatinine clearance 30 using the formulas in the protocol 