To compare protracted venous infusion (PVI) fluorouracil (5-FU) with PVI 5-FU plus mitomycin (MMC) in patients with advanced pancreatic cancer in a multicenter, prospectively randomized study.Two hundred eight patients were randomized to PVI 5-FU (300 mg/m(2)/d for a maximum of 24 weeks) or PVI 5-FU plus MMC (7 mg/m(2) every 6 weeks for four courses). The major end points were tumor response, survival, toxicity, and quality of life (QOL).The two treatment groups were balanced for baseline demographic factors, and 62% had metastatic disease. The overall response rate was 8.4% (95% confidence interval [CI]) 3.2% to 13.7% for patients treated with PVI 5-FU alone compared with 17.6%; 95% CI 10.3% to 25.1% for PVI 5-FU plus MMC (P =.04). Median failure-free survival was 2.8 months for PVI 5-FU and 3.8 months for PVI 5-FU plus MMC (P =.14). Median survival was 5.1 months for PVI 5-FU and 6.5 months for PVI 5-FU plus MMC (P =.34). Toxicities in both arms were mild. There was an increased incidence of neutropenia in the 5-FU plus MMC arm (P <.01), although no differences in infection were seen. No patients developed hemolytic uremic syndrome. Global QOL improved significantly after 24 weeks of treatment compared with baseline for patients receiving 5-FU plus MMC, although there was no statistically significant difference in QOL between arms.PVI 5-FU plus MMC resulted in a superior response rate in comparison with PVI 5-FU alone in advanced pancreatic cancer, but this did not translate into a survival advantage. These results emphasize the importance of chemotherapy in this setting and the continuing value of the fluoropyrimidines in pancreatic cancer.