CD4 and breast cancer: In addition, in the neoadjuvant setting, several authors reported a positive significant association between pCR rates and high levels of total T cells (CD3+) [25,51,52,53,54], as well as high infiltration of T helper (CD4+) [55] subsets and cytotoxic (CD8+) [27,53,54,56,57] in multiple retrospective series of unselected BC patients receiving neoadjuvant chemotherapy (anthracycline, anthracycline+taxane or taxane).