Assessment of the Lymph Node Status in Patients Undergoing Liver Resection for Intrahepatic Cholangiocarcinoma: the New Eighth Edition AJCC Staging System

Abstract

Introduction: The role of routine lymphadenectomy for intrahepatic cholangiocarcinoma (ICC) is still controversial. The AJCC eighth edition recommends a minimum of six harvested lymph nodes (HLNs) for adequate nodal staging. We sought to define outcome and risk of death among patients who were staged with ≥6 HLNs versus <6 HLNs.

Materials and methods: Patients undergoing hepatectomy for ICC between 1990 and 2015 at 1 of the 14 major hepatobiliary centers were identified.

Results: Among 1154 patients undergoing hepatectomy for ICC, 515 (44.6%) had lymphadenectomy. On final pathology, 200 (17.3%) patients had metastatic lymph node (MLN), while 315 (27.3%) had negative lymph node (NLN). Among NLN patients, HLN was associated with 5-year OS (p = 0.098). While HLN did not impact 5-year OS among MLN patients (p = 0.71), the number of MLN was associated with 5-year OS (p = 0.02). Among the 317 (27.5%) patients staged according the AJCC eighth edition staging system, N1 patients had a 3-fold increased risk of death compared with N0 patients (hazard ratio 3.03; p < 0.001).

Conclusion: Only one fourth of patients undergoing hepatectomy for ICC had adequate nodal staging according to the AJCC eighth edition. While the six HLN cutoff value impacted prognosis of N0 patients, the number of MLN rather than HLN was associated with long-term survival of N1 patients.

Keywords: ICC; Nodal status; Staging; Surgery.