Abstract:Background and Aims Lymph node metastasis (LNM) markedly impairs survival in patients with perihilar cholangiocarcinoma (pCCA). However, reliable preoperative predictors of pathological LNM remain limited. This study aimed to identify independent preoperative predictors of LNM and to develop a clinically applicable prediction model.Methods A total of 327 consecutive patients with pCCA who underwent curative-intent resection between October 2020 and October 2024 at the First Affiliated Hospital of Army Medical University (Southwest Hospital) and the Affiliated Hospital of Qinghai University were retrospectively enrolled. Patients were stratified into LNM-positive (n=131) and LNM-negative (n=196) groups according to postoperative pathological findings. Baseline characteristics were compared between the two groups. Univariate and multivariable logistic regression analyses were performed to identify independent predictors of pathological LNM. A nomogram was subsequently constructed based on the multivariable model.Results Patients with LNM had significantly shorter median overall survival (16.0 months vs. 42.0 months) and recurrence-free survival (12.0 months vs. 32.0 months) compared with those without LNM (both P<0.001). Multivariable logistic regression analysis demonstrated that age ≥65 years was a protective factor (OR=0.556, P=0.021), whereas CA19-9≥200 U/mL (OR=2.266, P=0.001) and radiologic suspicion of nodal involvement (OR=2.917, P=0.001) were independently associated with an increased risk of pathological LNM. The resulting nomogram demonstrated the ability to provide an individualized quantitative estimate of preoperative LNM risk.Conclusion Age, CA19-9 level, and radiologic nodal status independently predict pathological LNM in pCCA. The proposed nomogram provides a simple and clinically practical tool for preoperative risk stratification and surgical planning.