Prophylactic hepatic irradiation following curative resection of pancreatic cancer

Background/Purpose. It is unlikely that adjuvant chemoradiotherapy applied to the pancreatic bed alone significantly improves the survival of patients with resectable pancreatic cancer. The aim of the present study was to determine whether prophylactic hepatic irradiation (PHI) improved patient outcome after the curative resection of pancreatic cancer. Methods. The study population was comprised of 34 patients (PHI group) who were administered PHI after curative resection of pancreatic cancer between September 1994 and December 2003. The whole liver was irradiated with a total dose of 19.8-22.0 Gy under continuous infusion of 5-fluorouracil. The cumulative rate of liver metastasis and the survival outcomes of the PHI group were compared with those of 31 patients without PHI (non-PHI group) who underwent curative resection of pancreatic cancer. Results. The planned PHI was completed for 32 of the 34 patients. Two patients developed complications that might have been PHI-related. One developed liver abscesses which were successfully managed by percutaneous drainage. The other died of liver failure without recurrence 11 months after the operation. The cumulative incidence of liver metastasis was significantly lower for the PHI group than the non-PHI group (P=0.0455). Patients in the PHI group also survived significantly longer compared to those in the non-PHI group (P=0.0002). Conclusions. The present findings suggest that PHI is well tolerated and is a potentially effective treatment strategy after curative resection of pancreatic cancer, thereby providing the basis for a randomized controlled trial.