Intrahepatic cholangiocarcinoma patients without indications of lymph node metastasis not benefit from lymph node dissection

Background: To investigate the necessity of routine lymph node dissection (LND) in intrahepatic cholangiocarcinoma (ICC) patients without indications of lymph node metastasis (LNM) preoperatively. Methods: 422 consecutive ICC patients who undergone curative resection from January 2009 to December 2014 were enrolled and categorized as two groups (hepatectomy only or hepatectomy plus LND). Clinicopathologic data was compared between the groups by.2 or Fisher's exact test. Overall survival (OS) and recurrence-free survival (RFS) were calculated by the Kaplan-Meier method and differences were analyzed using the log-rank test. Cox regression model was adopted for multivariable analysis. Results: The median OS time of all 422 patients was 41.4 months. One-, 3-, and 5-year OS was 67%, 47%, and 35%, respectively. A total of 73 patients had undergone curative resection combined with LND, of whom 20.5% (15/73) were confirmed lymph node positive pathologically. The clinicopathologic characteristics between LND and control groups showed no significant differences. Of the 422 patients, 271 patients had recurrence. The recurrence rates were 65.8% for the LND group and 63.9% for the non-LND group. Survival analysis revealed that, neither the OS (LND vs. non-LND: 32.2 months vs. 46.2 months; p = 0.16) nor the RFS (LND vs. non-LND: 23.1 months vs. 17.0 months; p = 0.09) had significant difference. Multivariate analysis revealed that tumor size, tumor number, carbohydrate antigen19-9, carcinoembryonic antigen, and gamma-glutamyl transpeptidase were independent predictive factors for OS and RFS. Conclusion: Routine LND may not improve survival in resectable ICC patients with negative LNM diagnosis before operation.