Patients (26) with metastatic pancreatic or gastric adenocarcinoma were treated with 5-fluorouracil, adriamycin, and mitomycin C. One complete and 5 partial responses were observed among 15 patients with pancreatic adenocarcinoma (40% response rate) and 6 partial responses were observed among 11 patients with gastric adenocarcinoma (55% response rate). Responders had a significantly longer survival than nonresponders in both groups; in gastric adenocarcinoma the median survival of patients treated with this 3-drug combination was not superior to untreated historical controls.