Proposal of the minimal number of retrieved regional lymph nodes for accurate staging of distal bile duct cancer and clinical validation of the three‐tier lymph node staging system (AJCC 8th edition)

The minimal required number of retrieved lymph nodes (MNRLNs) to enable accurate staging of distal bile duct (DBD) adenocarcinoma remains unclear. The three-tier 8th N staging system of the American Joint Committee on Cancer (AJCC) for DBD adenocarcinoma has been recently released. The present study is aimed at proposing the MNRLNs for accurate staging and validating the 8th N stage.Between 1991 and 2015, patients with pathologically confirmed...