A Study on Radial Margin Status in Resected Perihilar Cholangiocarcinoma.

Abstract

To investigate radial margin (RM) status in resected perihilar cholangiocarcinoma (PHCC) and to evaluate the incidence of positive RM and its effect on survival. Although numerous studies have reported on ductal margin (DM) status in resected PHCC, no studies have addressed RM status. Patients who underwent hepatectomy for PHCC between 2001 and 2014 were retrospectively reviewed. After formalin fixation, resected specimens were serially sectioned at 5-mm intervals. All serial sections were color-copied, and RMs and DMs were identified and indicated on the color copies. Among 478 patients, 85 (17.8%) had positive surgical margins (R1 resection); of the 85 patients, 37 had positive RM alone, 33 had positive DM alone, and the remaining 15 had both positive RM and positive DM. Overall, 52 (61.2%) patients had positive RM. The sites of positive RM included the liver transection plane (n = 20) and the dissection plane in the hepatoduodenal ligament (n = 32). RM positivity on the liver transection plane was higher in left hepatectomy than in other hepatectomies (9.2% vs 1.9%, P < 0.001). RM positivity in the hepatoduodenal ligament was higher in left-sided hepatectomy than in right-sided hepatectomy (8.7% vs 3.6%, P = 0.031). The survival of the patients with positive RM was poorer than that of R0 patients (MST 2.1 vs 4.9 yrs, P < 0.001) and was similar to that of patients with positive DM. Multivariate analysis identified positive RM as one of the independent prognostic factors. Positive RM was the most common cause of R1 resection of PHCC and had similarly negative effects on survival as positive DM. Meticulous handling of the resected specimen is important to accurately evaluate RM status together with DM status.