Immunohistochemical (IHC) staining for programmed death-ligand 1 (PD-L1) on formalin-fixed paraffin-embedded (FFPE) tissue specimens has been shown to predict clinical response to programmed death-1 (PD-1)/PD-L1 immune checkpoint therapies in NSCLC [3,5,6,7,8,9,10,11,12]; hence, PD-L1 expression in FFPE tissue is used for selecting patients for immunotherapy. This evidence concerns the gene CD274 and non-small cell lung carcinoma.