The Prognostic Significance of PD‐L1 Expression and Associated Tumor‐Infiltrating Lymphocytes in Supraglottic Laryngeal Squamous Cell Carcinoma

ABSTRACT Laryngeal squamous cell carcinoma (LSCC) is characterized by diverse profiles of tumor‐infiltrating lymphocytes (TILs). We aimed to investigate the potential prognostic role of TILs and programmed death‐ligand 1 (PD‐L1) in patients with supraglottic LSCC. The expression of PD‐L1 and TILs was assessed using immunohistochemistry in 39 patients with primary supraglottic LSCC and correlated with clinicopathological characteristics and disease‐free survival (DFS). Survival curves were measured using the Kaplan–Meier method, and differences in survival between the groups were estimated using the log‐rank test. TIL density was significantly higher in PD‐L1‐positive (combined positive score: CPS ≥ 1) than in PD‐L1‐negative (CPS < 1) patients ( p = 0.000). Lower PD‐L1 expression was significantly associated with a locoregional recurrence (Fisher's exact test, p = 0.008). DFS was significantly longer in patients with CPS ≥ 1 than in those with CPS < 1 (Log‐rank test, p = 0.004). Multivariate Cox regression analysis showed that a low CPS ( p = 0.003) and positive nodal status ( p = 0.012) were statistically significant and independent predictors of malignancy recurrence. PD‐L1 represents a valuable marker for predicting recurrence and shorter survival after definitive therapy.