CD274 and neoplasm: The determination of the expression of PD-L1, not just on tumor cells but also on TME cells is particularly demonstrative since the combined determination is predictive of response (ORR: 22% if PD-L1 ≥ 1% vs. 4% if PD-L1 < 1% p = 0.021) and of survival (OS:10 months if PD-L1 ≥ 1% vs. 5 months if PD-L1 < 1%) [7].