Extended Lymphadenectomy Versus Regional Lymphadenectomy in Resectable Hilar Cholangiocarcinoma

Aim The aim of this study is to compare the effects of extended lymphadenectomy (E-LD) and regional lymphadenectomy (R-LD) on outcome after radical resection of hilar cholangiocarcinoma (HCCA). Methods Data of 290 patients who underwent radical resection of HCCA were retrospectively analyzed. Demographic characteristics, surgical variables, and tumor and LN characteristics were evaluated for association with survival. Results A total of 63 patients underwent E-LD. Patients who underwent E-LD were more likely to have portal vein embolization (14.3% vs. 5.7%), radical hepatectomy (36.2% vs. 26.0%), higher proportion of M1 patients (22.2% vs. 5.3%), more lymph nodes (LNs) retrieved (17 vs. 7), and positive common hepatic artery lymph nodes (21.4% vs. 12.6%) when compared with R-LD (all P < 0.05). The Kaplan–Meier curve of overall survival for patients who underwent E-LD indicated improvement over patients who underwent R-LD in M0 (33.39 vs. 21.31 months; P = 0.032) and R0 resection (32.97 vs. 21.02 months; P = 0.044) disease, but not observed in M1 disease ( P > 0.05). After propensity score matching, E-LD was not associated with a significant improvement in overall survival (OS) even in all subgroup analysis (all P > 0.05). On multivariable analysis, E-LD was associated with improved overall survival, but not after propensity score matching. Conclusion E-LD is more likely to be performed in higher stage tumors. E-LD significantly increases LN retrieval, thereby preventing under-staging and improving survival prediction. E-LD should not be adopted for HCCA patients with intraoperatively confirmed distant LN metastases. Future studies are required to further assess whether E-LD should be performed in negative celiac, superior mesenteric, and para-aortic lymph node in HCCA patients.