Correlation of PD-L1 Expression with TILs CD8+ in Non-small Cell Carcinoma Lung Cancer

Abstract

Background
Non-small cell lung cancer (NSCLC) is an epithelial carcinoma of the lung which consists of adenocarcinoma, squamous cell
carcinoma (SCC), and large-cell carcinoma (LCC). In a microtumor environment, PD-L1 and PD-1 bonds are immune checkpoints
that act in suppressing the activity of CD8+ TILs, thus affecting the prognosis of NSCLC. Aims of this study is to determine the
correlation between PD-L1 expression with CD8+
TILs in NSCLC.
Methods
This was a cross-sectional study of NSCLC registered in Department of Anatomical Pathology Faculty of Medicine University of
Sriwijaya/Dr. Moh. Hoesin Palembang Hospital since 1 January 2017 to 31 January 2020 with a total of 24 samples. All samples
were immunostained using PD-L1 and CD8 antibodies. PD-L1 expression was assessed in tumor mass and CD8 expression in
intratumoral and peritumoral TILs.
Results
Only two subtypes, adenocarcinoma and SCC, were found in this study. Adenocarcinoma was the most frequent subtype (54.1%),
sample group is dominated by <60 years old and was the subtype that expressed the PD-L1 most strongly (TPS ≥50%). There was
not significant correlation between PD-L1 expression with CD8+ TILs in NSCLC (p=0.679 and p=0.826) but based on
clinicopathological characteristics, there was a significant relationship between PD-L1 with disease stage and between intratumoral
CD8+ TILs density with disease stage (p=0.048 and p=0.017).
Conclusion
Adenocarcinoma subtype had stronger expression of PD-L1 compared to SCC. There was no correlation between PD-L1 and CD8+
TILs density in NSCLC.