CD8A and gastric adenocarcinoma: The experimental results in this paper showed that compared with adjacent tissues, the infiltration degree of CD8+ T cells in gastric adenocarcinoma tissue was significantly lower (Z = 2.244, P = 0.025, P < 0.05), and the infiltration degree of cells was significantly lower (Z = 2.785, P = 0.005, P < 0.05).