الفهرس | Only 14 pages are availabe for public view |
Abstract Background: In Egypt, gastric cancer (GC) is the 12th most prevalent cancer overall for both sexes. It is the fifth most common cancer globally and the third main cause of cancer mortality. Strategies for cancer immunotherapy have been created based on understanding of the interactions between the immune system and cancer. Immune checkpoint regulators are among the most crucial of these tactics. One important immune response checkpoint and a target for cancer immunotherapy is the programmed death (PD) 1 pathway. Anti-PD-L1 antibodies have been effective in clinical trials for treating a variety of malignancies. The Food and Drug Administration (FDA) has approved the clinical use of certain of these antibodies. Objectives: Detection of immunohistochemical (IHC) expression of PD-L1 by tumor cells (TC), tumor infiltrating lymphocytes (TILs) and combined positive score (CPS) in gastric cancer. Investigation of the possibility of using it as a targeted therapy, as well as, correlation of this expression with the clinicopathologic parameters of the tumors. Materials and methods: Gastrectomy specimens were used to collect 60 GC tissue slices. In TC, TILs, and CPS, PD-L1 IHC expression was studied. Results: TC PD-L1 expression was detected in 56.7% of cases, TILs PD-L1 expression was detected in 53.3 % of cases and CPS PD-L1 expression was detected in 63.3% of case, with No statistically significant correlation with clinico-pathological parameters except TILs PD-L1 expression showed statistically significant correlation with positive TILs (P value ˂0.019). Conclusion: Our findings supported the expression of PD-L1 by TC, TILs, and CPS in gastric cancer, with increased expression in a subpopulation of TILs rich in PD-L1 identifying them as potential targets for PD-1/PD-L1 therapy. |