CD274 and neoplasm: Our retrospective analysis of PD-L1 expression in salivary gland carcinoma cells and in its tumor infiltrating immune cells reports the following major findings:Expression of PD-L1 (by means ≥1% of the cells with PD-L1 positivity) was present in the salivary gland carcinoma cells of 17% and in the TIIC of 20% of the patients.