CD4+ follicular helper T (Tfh) cells infiltrating breast tumors predict patient survival. This study investigated the role of CD4+ T cells in breast cancer (BC) by analyzing their infiltration in tumors and their association with patient prognosis. CD4+ T cells, including Tfh, Th1, Th2, Th17, and Tregs, were identified in tumor tissues. Tfh cells, previously not found in solid tumors, were found to be associated with extensive immune infiltration and CXCL13 production, which is linked to organized antitumor immunity. An 8-gene Tfh signature was identified that strongly predicted survival or preoperative response to chemotherapy. The presence of Tfh cells in tumors was found to be a prognostic factor, suggesting their importance in immune responses against BC. The study also showed that extensively infiltrated tumors had higher levels of Tfh cells and were less immunosuppressive, with a higher frequency of organized lymphoid structures. The presence of Tfh cells in tumors was associated with better clinical outcomes, including improved survival and response to chemotherapy. The study highlights the role of Tfh cells in antitumor immunity and their potential as a prognostic marker in BC.CD4+ follicular helper T (Tfh) cells infiltrating breast tumors predict patient survival. This study investigated the role of CD4+ T cells in breast cancer (BC) by analyzing their infiltration in tumors and their association with patient prognosis. CD4+ T cells, including Tfh, Th1, Th2, Th17, and Tregs, were identified in tumor tissues. Tfh cells, previously not found in solid tumors, were found to be associated with extensive immune infiltration and CXCL13 production, which is linked to organized antitumor immunity. An 8-gene Tfh signature was identified that strongly predicted survival or preoperative response to chemotherapy. The presence of Tfh cells in tumors was found to be a prognostic factor, suggesting their importance in immune responses against BC. The study also showed that extensively infiltrated tumors had higher levels of Tfh cells and were less immunosuppressive, with a higher frequency of organized lymphoid structures. The presence of Tfh cells in tumors was associated with better clinical outcomes, including improved survival and response to chemotherapy. The study highlights the role of Tfh cells in antitumor immunity and their potential as a prognostic marker in BC.