Phase II study of gemcitabine and cisplatin in the treatment of patients with advanced pancreatic carcinoma.

Abstract

Pancreatic carcinoma is considered among the most chemoresistant of human malignancies. The most commonly used cytotoxic single agents, 5-fluorouracil and 2'-deoxy-2',2'-difluorocytidine (gemcitabine), have objective response rates of less than 10% in large studies. Hypothesizing noncross resistance and a synergistic interaction between gemcitabine and cisplatin, early clinical studies have demonstrated significant activity with this combination in patients with several types of malignant disease. A Phase II study was undertaken to determine the efficacy of gemcitabine in combination with cisplatin in patients with locally advanced and metastatic pancreatic carcinoma based on these considerations. The eligibility criteria included histologically confirmed, locally advanced, unresectable or metastatic exocrine carcinoma of the pancreas with no prior gemcitabine therapy; prior adjuvant therapy was allowed provided the last day of therapy was at least 6 months prior to starting treatment; clinically measurable or evaluable disease; a Southwest Oncology Group scale performance status of 0-2; a life expectancy of > 12 weeks; and adequate bone marrow, hepatic, and renal function. A total of 42 patients, 4 patients with locally advanced, unresectable disease and 38 patients with metastatic disease, were treated and received a total of 211 cycles of therapy between May 1997 to March 1999. The median age of patients was 61.5 years. The patients were treated in the outpatient setting with a combination of gemcitabine 1,000 mg/M(2) intravenously over 30 minutes administered on Days 1, 8, and 15 of each cycle and cisplatin 50 mg/M(2) intravenously administered after gemcitabine infusion on Days 1 and 15 with adequate prehydration accompanied by adequate urinary output. Cycles were repeated every 28 days. Response and toxicity were assessed according to World Health Organization and standard criteria. The complete and partial response rate among all 42 registered patients was 11 of 42 patients (26%; 95% confidence interval, 0.14-0.42). Stabilization of disease was seen in 15 patients (38%). Two additional patients with metastatic disease who achieved major responses to chemotherapy were rendered free of disease surgically, achieving a complete response status. The median overall survival was 7.1 months (95% confidence interval [CI], 6.3-9.1 months), with 64% of patients alive at 6 months and 19% of patients alive at 12 months. The median time to disease progression was 5.4 months (range, 0.9-20.8 months). Major toxicities were neutropenia and thrombocytopenia, with one episode of neutropenic fever. The combination of gemcitabine and cisplatin appeared to have significantly greater activity than single-agent gemcitabine in this Phase II study, with tolerable toxicity. The antitumor activity of this combination needs to be confirmed in multi-institutional or comparative trials.