Radiation therapy and 5-fluorouracil modulated by leucovorin for adenocarcinoma of the pancreas. A phase I study.

This Phase I study was designed to build on the Gastrointestinal Tumor Study Group's experience with combined modality therapy in patients with pancreatic cancer. Thirteen patients with adenocarcinoma of the pancreas received weekly 5-fluorouracil by rapid intravenous infusion midway through a 2-h infusion of high dose leucovorin during external beam radiation therapy. Twelve patients received 100% of planned external beam radiation; treatment delays occurred in only three. Four patients received 100% of planned chemotherapy doses. Leukopenia and thrombocytopenia caused reduction of the number of chemotherapy doses given during radiation in six patients; diarrhea, severe nausea and vomiting, and wound abscess caused reduction in three patients. Ten patients were evaluable for response; two had complete responses, one had a partial response, and two had minor responses. In this small series baseline and post-treatment CA 19-9 levels predicted and correlated with response. We conclude that radiation and 5-FU modulated by leucovorin is a tolerable treatment regimen for carcinoma of the pancreas, with preliminary suggestion of activity, that warrants further Phase II testing.