Abstract
BACKGROUND: The number of lymph nodes to be removed during tumor resection in patients with intrahepatic cholangiocarcinoma (ICC) has always been a subject of controversy. The correlation between examined lymph nodes (ELN) and cancer-specific mortality (CSM) in individuals with ICC was the purpose of this investigation. METHODS: Multivariable models were used to analyze data from the Surveillance, Epidemiology, and End Results database on ICC in order to ascertain the connection between ELN count and CSM. Correlation between ELN and cancer-specific survival (CSS) was evaluated by restricted cubic splines (RCS) on a continuous scale. Locally weighted scatterplot smoothing smoother was used to evaluated the hazard ratios (HRs) of ELNs for CSS with the structural breakpoints determined by Chow test. RESULTS: This investigation incorporated 1335 ICC cases. Independent risk factors for CSM included median household income, race, diagnostic year, tumor grade, clinical stage, pT stage, pN stage, pM stage and ELN count. With the adjustment for covariates, ICC cases showed statistically significant improvements in CSS (HR = 0.88) as the ELN count increased. The best threshold ELN count, as determined by cut-point analysis, was 6, which allowed for accurate CSS probability discrimination. CONCLUSION: Increasing ELN count indicated better CSS. Our results strongly suggested 6 ELNs as the optimal cut-off number for assessing the standard of lymph node inspection and prognostic classification in ICC.