RESULTS OF A PHASE II STUDY of AAFC in 32 patients with advanced measurable gastrointestinal cancer are presented. Fourteen patients were treated with a weekly schedule, while 18 were treated with 5-day courses of the drug. There were 12 patients with pancreas cancer, eight with stomach cancer, seven with cancer of the esophagus, four with colorectal cancer, and one with cancer of the gallbladder. Response was observed in pancreas and stomach cancer. Two patients with pancreas cancer had partial remissions, three other patients (two pancreas and one stomach) had response of short duration, considered to be less than a partial remission. There appeared to be very little difference between the two different schedules of administration. AAFC shows limited activity in adenocareinoma of pancreas and stomach; there does not appear to be a practical application for AAFC as a single agent.