Significance of expression of PD-L1, VEGF and CD8+ T cells in ovarian serous carcinoma: an Immunohistochemical study

: Background : Ovarian cancer is a lethal gynecological malignancy worldwide. The immune system plays a key role in preventing tumor development. Angiogenesis and immune evasion are vital for ovarian cancer progression and metastasis. Aim : This work aimed to evaluate the expression of PD-L1, VEGF and CD8 +T cells in ovarian serous carcinomas and correlate them with clinic-pathological variables. Material and methods : An Immunohistochemical study of PD-L1, VEGF and CD8+ T cells was performed on 50 cases of ovarian serous carcinomas. Results : PD-L1 & VEGF were over-expressed with statistical significance , in higher grade ( P <.01), advanced stage , case with lymph node metastasis and distant metastasis( P <.05) .Higher CD8+ T cells in epithelium and stroma was related to advanced stage, only intraepithelial CD8+ T cells was directly correlated with tumor grade & lymph node metastasis & stage ( P <.05). Positive correlation between PD-L1 & VEGF and Intraepithelial CD8+T cells was detected ( r =.048) Conclusion : Neoplastic cells in ovarian serous carcinomas-expressing PD-L1 and VEGF along with intraepithelial CD8+T cells-might expect poor prognosis. An association between PD-L1 and VEGF could predict their role in immune evasion.