Is routine lymph node dissection recommended for liver resection of intrahepatic cholangiocarcinoma? A systematic review and meta-analysis

Background/purpose: This meta-analysis aimed to elucidate the therapeutic effects of routine lymph node dissection (LND) with liver resection on intrahepatic cholangiocarcinoma (ICC). Controlled Trials, were searched to identify studies comparing LND and non-LND for ICC liver resection. The primary outcome was overall survival (OS), and secondary outcomes were disease-free survival (DFS), in-hospital morbidity, blood loss, and R0 rate. Results: Seventeen studies involving 4407 patients were included. The OS did not differ between the LND (n = 2158) and non-LND (n = 2249) groups (HR, 1.05; 95% CI, 0.83-1.32). The secondary outcomes did not differ significantly between the groups. Subgroup analyses stratified by the risk of bias showed a significant difference in OS between the high- and low-risk groups (P = 0.0008). In the low-risk group, LND (vs. non-LND) was associated with superior OS (HR, 0.76; 95% CI, 0.59-0.98). Most studies in lowrisk groups involved patients who were clinically node-negative. Conclusions: The therapeutic effects of routine LND for ICC have not been demonstrated. However, LND had a positive impact on OS in studies with a low risk of bias, thus suggesting that there may be a subset of ICC patients who would benefit from LND.