PD-L1 expression in urothelial bladder cancer varies more among specimen types than between companion assays.

ABSTRACT: Urothelial bladder cancer (UBC) patients ineligible to platinum-based chemotherapy can be treated with immune-checkpoint inhibitors (ICI) in Programmed Death Ligand 1 (PD-L1) positive cases. Although concordance exists between different PD-L1 assays, little is known on PD-L1 expression variability in matched UBC samples. We compared PD-L1 expression in whole slides of matched transurethral resections (TURBT), radical cystectomies (RC), and lymph node metastasis (LN). Immunohistochemistry using the VENTANA PD-L1 (SP263) assay was performed on 115 patients and scored positive if expression occurred in ≥25% immune cells (IC), ≥25% tumour cells (TC), or both. PD-L1 was positive in 42.7% TURBT, 39.8% RC, and 27.3% LN specimens. Concordance was moderate (κ=0.52; P<0.001) between TURBT and RC, an

SUBMITTER: de Jong JJ 

PROVIDER: S-EPMC8516767 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature