CD4 and breast cancer: According to prior studies, peripheral T lymphocyte subsets can predict the clinical outcome of breast cancer, and regulatory B cells can exert immunosuppressive function by acting on tumor cells.11-13 The decrease of CD3+T cell count in patients with malignant tumors can significantly affect the initiation, induction and effect of immune response; the reduction of CD4++T cell count can reduce the specific anti-tumor effect; the increase of CD8+T cell count may strengthen cytotoxicity.14-16