Impact of Tumor Subclassifications for Identifying an Appropriate Surgical Strategy in Patients with Intrahepatic Cholangiocarcinoma.

Abstract

Intrahepatic cholangiocarcinoma (ICC) is subclassified into small and large duct types. The impact of these subclassifications for identifying appropriate surgical strategies remains unclear. This study included 118 patients with ICC who underwent liver resection. Based on the pathological examination results, the participants were divided into the small duct-type ICC group (n = 64) and large duct-type ICC group (n = 54). The clinicopathological features and postoperative outcomes were compared between the two groups to investigate the impact of subclassification for selecting appropriate surgical strategies. Ten patients in the small duct-type ICC group had synchronous or metachronous hepatocellular carcinoma. The large duct-type ICC group had higher proportions of patients who underwent major hepatectomy, extrahepatic bile duct resection, portal vein resection, and lymph node sampling or dissection than the small duct-type ICC group. The large duct-type ICC group had significantly higher incidences of lymph node metastasis/recurrence and pathological major vessel invasion than the other. The small duct-type ICC group exhibited significantly higher recurrence-free and overall survival rates than the large duct-type ICC group. Further, the large duct-type ICC group had a significantly higher incidence of lymph node metastasis/recurrence than the small duct-type ICC at the perihilar region group. Suitable surgical strategies may differ between the small and large duct-type ICCs. In patients with large duct-type ICCs, hepatectomy with lymph node dissection and/or biliary reconstruction should be considered, whereas hepatectomy without these advanced procedures can be suggested for patients with small duct-type ICCs.