McGrail et al. reported that, in lung and bladder cancers where CD8 T cell counts positively associated with neoantigen load, high-TMB tumors demonstrated significantly higher objective response rates than low-TMB tumors, while this trend was not observed in breast and prostate cancers which show no correlation between CD8 T cell counts and neoantigen load (14). The gene discussed is CD8A; the disease is prostate carcinoma.