3. Measurable disease at presentation: Either by Response Evaluation Criteria in Solid Tumors (RECIST) or by measurement of serum markers (calcitonin, carcinoembryonic antigen (CEA), prostate specific antigen (PSA) or cancer antigen 125 or carbohydrate antigen 125 (CA-125) in the dose-finding portion of the study; with disease measurable by RECIST required only in the phase II cohort.