Programmed cell death ligand-1 (PD-L1)‎ expression combined with CD8 tumor infiltrating lymphocytes density in non-small cell lung cancer patients

Abstract EN

Cancer immunotherapy targeting programmed cell death-1/programmed cell death ligand-1 (PD-1/PDL1) pathway has shown promising results in treatment of non-small cell lung cancer (NSCLC) patients.

T cells play a major role in tumor-associated immune response.

This study aimed to investigate PD-L1 expression alone and combined with CD8 tumor infiltrating lymphocytes (TILs) density in relation to clinicopathologic parameters and survival in NSCLC patients.

Immunohistochemical analysis was used to evaluate PD-L1 expression and CD8 TILs density in 55 NSCLC patients.

PD-L1 immunopositivity was detected in 36 (65.5%) of NSCLC cases.

PD-L1 expression was significantly related to high tumor grade (p value = 0.038) and low CD8 TILs density (p value = 0.004), whereas no significant relations were detected between PD-L1 expression and tumor stage (p value = 0.121), overall survival (OS) (p value = 0.428) and progression-free survival (PFS) (p value = 0.439).

Among PD-L1/CD8 TILs density groups, PD-L1+/CD8Low group was significantly associated with high tumor grade compared to PD-L1/ CD8high group (pairwise p = 0.016).

PD-L1+/CD8Low group was significantly related to advanced tumor stage compared to PD-L1+/CD8high and PD-L1/CD8Low groups (pairwise p = 0.001 and 0.013 respectively).

PD-L1/CD8high group exhibited the best OS and PFS whereas PD-L1+/CD8low group had the poorest OS and PFS (p value = 0.032 and 0.001 respectively).

Assessment of PD-L1 combined with CD8 TILs density, instead of PD-L1 alone, suggested important prognostic relevance in NSCLC patients.