Clinical Significance of Biliary Vascular Anatomy of the Right Liver for Hilar Cholangiocarcinoma Applied to Left Hemihepatectomy

Abstract

To evaluate the influence of confluence pattern of the right posterior sectional bile duct (RPSBD) on clinocopathological outcome in patients with hilar cholangiocarcinoma who underwent left hemihepatectomy (LH). Biliary vascular anatomy may affect the cutting line of proximal bile ducts, especially in case of LH, because of the shorter distance from the sectional ramification to the ductal confluence. However, there were few studies as to the relationship between anatomic variation and clinocopathological outcome. A total of 209 patients with hilar cholangiocarcinoma underwent surgical resection. We retrospectively investigated confluence patterns of the RPSBD in relation to the right portal vein (RPV) by preoperative imaging studies in 63 patients who underwent LH, and classified them into 3 groups (supraportal type: the RPSBD runs cranially around the RPV; infraportal type: the RPSBD runs caudally to the RPV; combined type: one segmental duct runs infraraportally and the other supraportally to the RPV). Furthermore, the effects of these variations on clinocopathological outcome were evaluated. The supraportal type was observed in 53 cases (84.1%), the infraportal type in 8 cases (12.7%), and the combined type in 2 cases (3.2%). Although most of the clinocopathological features were similar between the groups, positive margin of proximal bile duct was significantly lower in the infraportal group, as compared with the supraportal group. Furthermore, it was noted that there was no incidence of bilioenteric anastomotic leakage in the infraportal group. Negative proximal margin and secure reconstruction were more easily achieved in the infraportal group than in the supraportal group. Preoperative evaluation of confluence pattern of RPSBD may be clinically useful for the management of hilar cholangiocarcinoma when applied to left-sided hepatectomy.