Quantitative Immunofluorescence Evaluation of PD-L1 Expression in Non-Muscle-Invasive and Muscle-Invasive Urothelial Bladder Cancer

Abstract

The expression of PD-L1 protein is quantified in 56 samples of urothelial bladder cancer (BC). PD-L1 expression is detected in all BC samples, while in non-muscle-invasive bladder cancer (NMIBC) this score is 1.5 times higher than in muscle-invasive bladder cancer (MIBC) (p = 0.001). High PD-L1 expression level (≥30%) is observed in 20% of MIBC samples and among NMIBC tumors in 68% of cases, i.e., 3.4 times more often (p = 0.0004). The last fact justifies the prospect of starting therapy with immune checkpoint inhibitors at the onset of the disease for NMIBC.