Preoperative neutrophil-to-lymphocyte ratio and overall survival after biliary tract cancer resection: A retrospective cohort study.

The comparative prognostic value of preoperative inflammatory markers in resected biliary tract cancer (BTC) remains uncertain. We evaluated the associations of neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) with overall survival (OS), focusing on NLR versus dNLR. This single-center retrospective cohort included 109 patients undergoing curative-intent resection. Exploratory cut-offs were derived using receiver operating characteristic analysis and the Youden index. Survival associations were assessed using Kaplan-Meier analysis and separate multivariable Cox models for NLR and dNLR to address multicollinearity. During follow-up, 70 patients died, and median OS was 19.43 months. Elevated NLR and dNLR were associated with shorter OS in univariable analyses. After adjustment, NLR ≥2.11 remained associated with shorter OS (hazard ratio, 4.043; 95% confidence interval, 1.199-13.635; p = 0.024), whereas dNLR ≥1.75 did not (p = 0.321). Neither marker was statistically significant when modeled continuously in adjusted analyses. PLR and LMR showed no statistically significant univariable associations with OS. Combining NLR, dNLR, and PLR yielded only modest discrimination (area under the curve, 0.666). These findings support further investigation of preoperative NLR as a prognostic marker in resected BTC. However, cohort-derived cut-offs and combined risk stratification remain exploratory and require validation in larger independent cohorts before clinical application.