Karnik T, et al. – The goal of this paper was to compare the performance of three different Programmed cell death–1 and its ligand–1 (PD–L1) antibodies (Ventana SP263, Dako 22C3 and BioCare RbMCAL10 antibodies) in invasive ductal carcinoma specimens. Owing to the high concordance, all three antibodies illustrated the same associations with all pathologic and clinical parameters studied. Standardization studies to identify reliable biomarkers assisting in patient selection for immune therapy were warranted to improve the risk–benefit ratio for these drugs.