Impact of Positive Radial Margin on Recurrence and Survival in Perihilar Cholangiocarcinoma

SIMPLE SUMMARY: The only potentially curative treatment of perihilar cholangiocarcinoma (PHC) is complete (R0) resection. This is difficult to achieve and great effort should be made to optimise surgical margins assessment and to thoroughly define their prognostic value. When considering resections for PHC, not only bile duct margins (ductal margins, DM), but also the liver transection plane and the dissection plane in the hepatoduodenal ligament (radial margins, RM) should be examined. Studies concerning PHC resections with comprehensive analyses of the recurrence and survival related to margins status most frequently consider only ductal margins. The importance of also assessing radial margins’ prognostic value was recently introduced and deserves to be further studied. To our knowledge, there is currently no evidence of prognostic value of isolated positive RM. Therefore, the aim of this study was to evaluate the incidence and to investigate the effects on the recurrence and survival of positive isolated RM in resected PHC. ABSTRACT: In resected perihilar cholangiocarcinoma (PHC), positive ductal margin (DM) is associated with poor survival. There is currently little knowledge about the impact of positive radial margin (RM) when DM is negative. The aim of this study was to evaluate the incidence and the role of positive RM. Patients who underwent surgery between 2005 and 2017 where retrospectively reviewed and stratified according to margin positivity: an isolated RM-positive group and DM ± RM group. Of the 75 patients identified; 34 (45.3%) had R1 resection and 17 had positive RM alone. Survival was poorer in patients with R1 resection compared to R0 (p = 0.019). After stratification according to margin positivity; R0 patients showed better survival than DM ± RM-positive patients (p = 0.004; MST 43.9 vs. 23.6 months), but comparable to RM-positive patients (p = 0.361; MST 43.9 vs. 39.5 months). Recurrence was higher in DM ± RM group compared to R0 (p = 0.0017; median disease-free survival (DFS) 15 vs. 30 months); but comparable between RM and R0 group (p = 0.39; DFS 20 vs. 30 months). In univariate and multivariate analysis, DM positivity resulted as a negative prognostic factor both for survival and recurrence. In conclusion, positive RM resections appear to have different recurrence patterns and survival rates than positive DM resections.