The Role of Lymph Node Dissection in Intrahepatic Cholangiocarcinoma: A Multicenter Retrospective Study. 

Background: Lymph node dissection (LND) is of great significance in intrahepatic cholangiocarcinoma (ICC). Although the National Comprehensive Cancer Network (NCCN) guidelines recommend routine LND in ICC, the effects of LND remains controversial. This study aimed to explore the role and application of LND in ICC. Methods: Patients were identified in two Chinese academic centers. Inverse probability of treatment weighting (IPTW) was used to reduce bias. Kaplan–Meier curves and Cox proportional hazards models were used to compare overall survival (OS) and disease-free survival (DFS). Results: Of 232 patients, 177 (76.3%) underwent LND, and 71 (40.1%) had metastatic lymph nodes. A minimum of 6 lymph nodes were dissected in 66 patients (37.3%). LND did not improve the prognosis of ICC. LNM >3 may have worse OS and DFS than LNM 1-3, especially in the LND >=6 group. For nLND patients, the adjuvant treatment group had better OS and DFS. Conclusions: CA 19-9, CEA, operative time, positive surgical margin, and T stage were independent risk factors for OS; CEA and differentiation were independent risk factors for DFS. LND has no definite predictive effect on prognosis. Patients with 4 or more LNMs may have a worse prognosis than patients with 1-3 LNMs. Adjuvant therapy may benefit patients of nLND.