CD274 and neoplasm: A high expression of PD-L1 seems to be correlated with a worse prognosis in several type of tumors, such as non-small cell lung cancer (NSCLC) [24,25], kidney cancer [26,27,28,29,30,31], and bladder cancer [32], while in other neoplasms, like melanoma [33], seems to be a good prognosis predictor.