Significant associations have been documented between high levels of infiltration by T effector cells (CD4+ and CD8+) and low levels of T regulatory cells (Tregs: FOXP3+ (forkhead box protein 3) and CTLA-4+ (cytotoxic T lymphocyte antigen-4)) and subsequent pCRs with NAC in primary breast tumours and ALN metastases [13–17]; (Kaewkangsadan et al., 2016b submitted for publication). The gene discussed is FOXP3; the disease is breast neoplasm.