In the work of Harding et al., patients with advanced HCC were treated with anti-CTLA-4 monotherapy [n = 1], anti-PD-1/PD-L1 monotherapy [n = 25], and anti PD-1/PD-L1 plus other agents, including anti-CTLA-4 [n = 1], anti-LAG3 [n = 2], and anti-KIR [n = 2]). Here, PDCD1 is linked to hepatocellular carcinoma.