Analysis of the clinical benefit of intraoperative radiotherapy in patients undergoing macroscopically curative resection for pancreatic cancer

Purpose: To determine the survival of pancreatic cancer patients treated wi th intraoperative radiotherapy (IORT) and/or external beam radiation therap y (EBRT) following macroscopically curative resection, Methods and Materials: One hundred and thirty-eight patients with pancreati c cancer who had undergone potentially curative total or regional pancreate ctomy between 1980 and 1997 were retrospectively analyzed. Among the 138 pa tients, 98 had a pathologically negative surgical margin and the remaining 40 patients had a positive surgical margin, The usual EBRT dose was 45-55 G y with a daily fraction of 1.5-2.0 Gy, The median IORT dose was 25 Gy in a single fraction. Results: The 2-gear cause-specific survival rate of patients with pathologi cally negative surgical margins was 19%, and that of patients with positive margins was 4% (p < 0,005), Although the median survival time (MST) of pat ients with negative margins treated with IORT and EBRT was significantly lo nger than that of those treated with operation alone (17 vs. 11 months), no significant difference in survival curves was observed, In patients with p ositive surgical margins in peripancreatic soft tissue, the difference betw een the survival curve of patients treated with surgery alone and that of t hose treated with surgery and radiation therapy was borderline significant (p < 0.10). Patients receiving intraarterial or intraportal infusion chemot herapy had significantly improved survival rates compared with those who di d not receive it (p < 0,05), Conclusion: Although the MST was longer in patients with negative margins r eceiving IORT and EBRT than in those receiving no radiation, improved long- term survival by IORT and/or EBRT was not suggested. In patients with posit ive margins, our results obtained by IORT/EBRT were encouraging. Randomized studies with much higher patient numbers are necessary to define the role of IORT in curatively resected pancreatic cancer. (C) 2000 Elsevier Science Inc.