Prognostic impact of the site of portal vein invasion in patients with surgically resected perihilar cholangiocarcinoma

BackgroundThe aim of this study was to determine the impact of the site of portal vein invasion on survival after hepatectomy for perihilar cholangiocarcinoma.MethodsThis study classified 168 patients undergoing resection for perihilar cholangiocarcinoma histologically as without portal vein resection or tumor invasion to the portal vein (PV0), with tumor invasion to unilateral branches of the portal vein (PVt3), or with tumor invasion to the main portal vein or its bilateral branches, or to unilateral second-order biliary radicals with contralateral portal vein involvement (PVt4). Patients in PVt4 were subclassified into the A-M group (cancer invasion limited to the tunica adventitia or media) or the I group (cancer invasion reaching the tunica intima).ResultsOf the patients, 121 were in PV0, 21 were in PVt3, and 26 were in PVt4. There was no difference in survival between the PV0 and PVt3 groups (P = .267). The PVt4 group had a worse prognosis than the PVt3 group (P = .046). In addition, the A-M (n = 19) and I subgroups (n = 7) of PVt4 had worse prognoses than the PV0 or PVt3 groups (P = .005 and < .001, respectively). All patients in the I subgroup of PVt4 died within 9 months after resection. On multivariate analysis, PVt4 (P = .029) was identified as an independent prognostic factor.ConclusionsIn perihilar cholangiocarcinoma, postoperative survival was no different between patients with and without ipsilateral portal vein invasion, although patients with tumor invasion to the main or contralateral branches of the portal vein, especially with tunica intima invasion, had extremely poor prognoses.