Tissue-resident memory CD8<sup>+</sup>T cells (CD8<sup>+</sup>T<sub>RM</sub>), a subset critical to cancer control that are excluded from blood, could also be aspirated from HCC for phenotypic/functional assessment (mean 10% <i>vs.</i> 0.1%, <i>p <</i>0.0001). The gene discussed is CD8A; the disease is cancer.