Background: In surgery for perihilar cholangiocarcinoma (PHCC), it is still controversial as to whether additional resection of the bile duct is needed on high grade (HG) biliary intraepithelial neoplasia (BilIN) margin.
Methods: Patients who underwent surgery for PHCC with curative intent between 2001 and 2015 were stratified by resection margin, and were analyzed comparing the clinical outcomes.
Results: Of the 306 study participants, 217 patients had negative margins (R0), 18 patients had HG BilIN, and 71 patients had positive margins (R1). The median overall survival was 36.0 months in the R0 group, 41.0 months in the HG BilIN group, and 25.0 months in the R1 group while overall survival rates at 5 years were 34.5% in the R0 group, 44.4% in the HG BilIN group, and 21.0% in the R1 group. The median disease-free survival was 15.0 months in the R0 group, 16.5 months in the HG BilIN group, and 12.0 months in the R1 group.
Conclusions: Although the HG BilIN group had neoplasia with malignant potential, survival and recurrence outcomes were comparable to those of the R0 group, which suggests that no additional resection is needed when the maximal bile duct margin in PHCC surgery contains HG BilIN.
Keywords: high grade biliary intraepithelial neoplasia; margins of excision; perihilar cholangiocarcinoma; recurrence; survival.
© 2020 Japanese Society of Hepato-Biliary-Pancreatic Surgery.