CD274 and non-small cell lung carcinoma: However, previous studies using commercial non-small cell lung cancer tumor samples have shown strong concordance for PD-L1 tumor cell staining at different cutoffs for three of the four immunohistochemistry assays (i.e., the Ventana SP263 and Dako 22C3 and 28-8 assays), with less agreement using the Ventana SP142 assay [23–25].