Supplementary file 1_Number of examined lymph nodes and overall survival in intrahepatic cholangiocarcinoma: a population-based study suggesting a staging benefit.docx

We aimed to clarify the role of LNY by examining its association with nodal detection and overall survival (OS).</p>Methods<p>We identified patients with surgically resected ICC (2004–2022) from the SEER database. Multivariable Cox models and inverse probability of treatment weighting (IPTW) stratified by nodal status were used to evaluate the association between LNY (≥6 vs <6) and OS.

Logistic regression examined predictors of nodal metastasis.</p>Results<p>LNY ≥6 was not independently associated with OS (HR 0.88, 95% CI 0.71–1.08; P = 0.209). Nodal metastasis (HR 2.29), advanced T category, larger tumor size, poor differentiation, male sex, and lack of chemotherapy were independently associated with worse OS. Notably, multiple tumors were associated with better OS than single tumors (HR 0.79), likely reflecting selection bias.