New cancer immune-prevention treatments include FDA-approved inhibitory antibodies such as pembrolizumab (anti-PD1 mAb), nivolumab (anti-PD1), and ipilimumab (anti–CTLA-4 mAb) (Bauman and Ferris, 2014; Ferris et al., 2018; Mehra et al., 2018; Havel et al., 2019); co-stimulation and co-inhibition pathways (Kuss et al., 2003; Tsukishiro et al., 2003; Baruah et al., 2012; Pardoll, 2012); and check-point blockade therapy (Davis et al., 2016; Muzaffar et al., 2021). This evidence concerns the gene PDCD1 and cancer.