Preoperative Neutrophil-to-lymphocyte Ratio Predicts Tumor-infiltrating CD8+ T Cells in Biliary Tract Cancer

Abstract

Background/aim: This study evaluated the prognostic significance of preoperative neutrophil-to-lymphocyte ratio (NLR) and CD8⁺ tumor-infiltrating lymphocytes (TILs), and whether preoperative NLR was associated with CD8⁺ TILs in biliary tract cancers (BTCs).

Patients and methods: A total of 154 patients with BTCs who underwent surgery were enrolled in this study. We obtained neutrophil and lymphocyte counts, and calculated NLR from preoperative peripheral blood samples. CD8⁺ TILs were identified by immunohistochemical staining.

Results: The overall survival (OS) and recurrence-free survival (RFS) of patients with high NLR were shorter than those with low NLR. The OS and RFS of patients with high CD8⁺ TILs were longer than those with low CD8⁺ TILs. Preoperative NLR and CD8⁺ TILs were negatively correlated.

Conclusion: NLR and CD8⁺ TILs were associated with OS and RFS in BTCs. NLR can predict CD8⁺ TILs infiltrating the cancer microenvironment.

Keywords: Neutrophil-to-lymphocyte ratio; biliary tract cancer; tumor infiltrating lymphocytes.