Background: The prognosis of patients with resected pancreatic cancer remains poor. This study evaluated the effect of adoptive immunotherapy (AIT) using intraportal infusion of lymphokine-activated killer (LAK) cells after curative resection and intraoperative radiation therapy (IORT) on advanced pancreatic cancer. Methods: Twenty-nine consecutive patients with advanced pancreatic cancer (Japan Pancreas Society stage III or IV) were divided into two groups. The control group (n = 17) underwent tumour resection and IORT. The treatment group (n = 12) underwent resection, IORT and intraportal infusion of LAK cells combined with recombinant interleukin 2 (rIL-2). The incidence of liver metastasis and the survival rate of these two groups were compared. Results: Although the overall survival between groups was not statistically different (P = 0.082), there were more patients (four) alive 3 years after operation in the test group (36 per cent versus zero), and the incidence of liver metastases in the treatment group was significantly lower (three of 12 versus ten of 15; P < 0.05). LAK therapy influenced survival positively in multivariate analysis. Conclusion: These preliminary observations suggest that AIT warrants further study as a possible adjuvant for patients undergoing curative resection and IORT for pancreatic cancer.