Secretin and cholecystokinin (CCK) have trophic effects on the pancreas and may therefore have a place in the treatment of pancreatic cancer. The present study was performed to examine whether these hormones may cause harm in patients with pancreatic cancer receiving cytostatics. The cytostatics were 5-fluorouracil, adriamycin, and mitomycin C(FAM). Secretin plus Thr28Nle31CCK25-33, in doses stimulating pancreatic secretion to about 60% of maximal, were given as a continuous 6-day intravenous infusion just before (four patients) or immediately after (five patients) starting treatment with FAM. Five patients received FAM only. When considering symptoms, laboratory findings, abdominal CT scans, and survival, no evidence was found that secretin and CCK may cause serious or unpleasant side effects in patients with pancreatic cancer receiving cytostatics.