CD274 and neoplasm: In both IHC reactions, SCC patients had significantly (p<0.05) higher median percentage of PD-L1-positive tumor cells than patients with non-SCC (70% compared to 15% of PD-L1-positive tumor cells stained with 22C3 and 32.5% compared to 1% of PD-L1-positive tumor cells stained with SP142 antibody).