Role of Lymph Node Dissection in Small (≤ 3 cm) Intrahepatic Cholangiocarcinoma

Background and Aims: The role of lymph node dissection (LND) in patients with small intrahepatic cholangiocarcinoma (ICC) is still under debate. The aims of this study were to compare the lymph node (LN) status and its correlation with survival among patients with ICC stratified by tumor size. Methods: A retrospective analysis of a multi-institutional series of 259 patients undergoing curative-intent surgery was carried out. Patients were stratified into Small-ICC (≤ 3 cm) and Large-ICC (> 3 cm) based on tumor size. Results: There were 53 and 206 patients in Small-ICC and Large-ICC groups, respectively. The incidence of LND was 62% among Small-ICC patients and 78% among Large-ICC patients (p = 0.016). LN metastases were identified in 30.3% and 38.5% of Small-ICC and Large-ICC patients, respectively (p = 0.37). No differences in terms of number of harvested LN and LN metastases were identified comparing Small- and Large-ICC patients. The 5-year overall survival (OS) was 52.6% for Small-ICC and 36.2% for Large-ICC (p = 0.024). The 5-year OS according to the LN status (N0 vs N+) was 84.8% and 36.0% (p = 0.032) in Small-ICC, and 45.7% and 12.1% in Large-ICC (p < 0.001), respectively. Conclusion: While Small-ICC patients with no LN metastasis had a good long-term survival, the LN resulted in an important variable associated with survival also for patients in this group. Moreover, the incidence of LN metastasis did not differ when comparing Small-ICC and Large-ICC patients, suggesting that LND is mandatory in the surgical treatment of ICC regardless of tumor size.