Compared with the low-risk group, the proportions of infiltrating tumor-killing immune cells, such as plasma cells, CD8 + T cells and M1 macrophages, in the THCA tissues of the high-risk group were significantly reduced, whereas those of infiltrating tumor-promoting immune cells, such as M2 macrophages and Tregs, were significantly increased [43, 44]. Here, CD8A is linked to neoplasm.