In the present study, we found that the methylation risk of BC patients was positively correlated with Th2 cells, while higher methylation risk was correlated with lower infiltration of Tem cells, Tcm cells, T helper cells, T cells, pDC, NK cells, NK CD56 bright cells, neutrophils, mast cell, iDCs, DCs, cytotoxic cells, CD8+ T cell, and B cells. This evidence concerns the gene CD8A and breast cancer.