A cohort study on the immunogenicity of COVID-19 vaccine BNT162b2 in cancer patients receiving immune checkpoint inhibitors either targeting programmed cell death protein 1 (PD-1) or programmed death-ligand 1 (PD-L1) showed a spike-specific T cell response, assessed by ELISpot, in 72% of patients after one dose and in 92% after the second dose [116]. This evidence concerns the gene PDCD1 and cancer.