Specifically, the two distinct macrophage phenotypes, the anti-tumoral “M1”-like and the pro-tumoral “M2”-like can secrete cytokines and other factors, which in turn affect PD-L1 expression and anti-tumor immune response [32,33] and only few recent studies have shown correlation of PD-L1 levels in tumor cells with macrophages phenotypes. This evidence concerns the gene CD274 and neoplasm.