Clinical impact of margin status on survival and recurrence pattern after curative-intent surgery for pancreatic cancer

Summary Background/Objective The definition of R0 resection for invasive pancreatic ductal carcinoma (IPDC) is important. However, there are different definitions among several countries in the world. Methods From 2001 to 2015, 100 consecutive patients with IPDC who underwent pancreatic resection in our hospital were enrolled. We compared survival and recurrence patterns between the R0 group and R1 group based on the UICC (Union for International Cancer Control) classification (current-R0 vs. current-R1) and based on our revised classification, which defines R0 as a surgical margin of >1 mm (revised-R0 vs. revised-R1). Results The 100 patients comprised 58 males and 42 females, and their median age was 70 [32–87]. There were 84 patients in the current-R0 group and 43 in the revised-R0 group. There was no difference in overall survival (OS) or recurrence-free survival (RFS) between the current-R0 group and current-R1 group. However, there was a tendency toward a higher OS rate in the revised-R0 than revised-R1 group (log-rank p = 0.065), and RFS was significantly better in the revised-R0 than revised-R1 group (log-rank p = 0.002). There was no significant difference in the recurrence patterns between the current-R0 and current-R1 groups. In contrast, the local recurrence rate was significantly lower in the revised-R0 than revised-R1 group (21% vs. 42%, respectively; p = 0.026). Conclusion The revised classification of surgical resection may be more useful than the current UICC classification for prediction of prognosis and local recurrence of IPDC.