CD274 and hepatocellular carcinoma: In early CheckMate 040 and KEYNOTE-224 studies, PD-L1 combined positive score (CPS), but not tumor proportional score (TPS), was significantly associated with response rate to anti-PD-1 nivolumab or pembrolizumab monotherapy in patients with advanced HCC (El-Khoueiry et al., 2017; Zhu et al., 2018).