Kim CG identified lower frequencies of effector/memory subtypes (CCR7- CD45RA-) in CD8+ T cells and higher frequencies of severely exhausted cells (TIGIT+) in tumor-reactive PD-1+ CD8+ T cells to predict HPD, with the area under the curve reaching 0.926 and 0.938 [13]. The gene discussed is CD8A; the disease is neoplasm.