the IVW method results showed that CD45RA- CD4+ %CD4+ (p-value:1.37×10−6), CD8dim %T cell (p-value:4.62×10−43), BAFF-R on IgD+ CD38- unsw mem (p-value:6.93×10−5), CD27 on PB/PC (p-value:2.72×10−18) lowered the risk of breast cancer. Here, CD4 is linked to breast cancer.