[Long-Term Survival after Surgery with Postoperative Chemotherapy for Perihilar Cholangiocarcinoma with Residual Invasive Carcinoma at Ductal Resection Margins-A Case Report].

A 64-year-old man with liver dysfunction was given a diagnosis of perihilar cholangiocarcinoma(Bismuth type Ⅳ). The tumor was predominantly right-sided and invaded to the bifurcation of the right and left portal veins. After confirming sufficient liver functional reserve and future liver remnant, the patient underwent extended right hepatectomy, extrahepatic bile duct resection, and portal vein resection and reconstruction. Intraoperative examination of frozen sections revealed the presence of residual invasive carcinoma on both the hepatic and duodenal sides of the ductal resection margins. However, we did not perform pancreaticoduodenectomy or additional resection of the margin-positive proximal bile duct considering the curability and invasiveness of these procedures. He received postoperative chemotherapy with biweekly gemcitabine plus cisplatin for 1 year, followed by gemcitabine monotherapy for 1 year, and S-1 monotherapy has been performed since then. He remains alive and well with no evidence of disease 63 months after surgery.