Eich ML, et al. - In this investigation, researchers sought to delineate the expression of PD-L1, CD8 and FOXP3 in tumor microenvironment in non-muscular invasive urothelial carcinoma (NMIBC) samples obtained through sequential biopsies and evaluate their potential role in the prediction of disease outcome. Investigators observed that tumors with >1% and> 5% PD-L1 expression were less likely to recur in tumor cells. Tumors with higher FOXP3 expression in peritumoral lymphocytes had lower risk of progression of grade. Tumors with > 1 expression ratio of FOXP3/CD8 in intratumoral lymphocytes had a lower risk of progression of grade. Although there was a higher number of positive lymphocytes of FOXP3, CD8 and PD-L1 after treatment with Bacillus Calmette-Guerin (BCG), the findings did not reach statistical significance. PD-L1 expression in tumor cells and peritumoral lymphocytes in patients without BCG treatment varied across serial biopsies.