CD274 and ovarian carcinoma: Spanning all histologic types of ovarian epithelial cancers, high PD-L1 expression in stromal tumor-infiltrating lymphocytes, tumor cells, and intraepithelial tumor-infiltrating lymphocytes was detected in 42 (16.9%), 21 (8.5%), and 26 (10.5%) patients of total 248 patients with ovarian epithelial cancers, respectively.