This study investigates the association between the expression of CD28 and PD-1 molecules on peripheral blood T cells and prognosis in advanced breast cancer (BC) patients undergoing paclitaxel chemotherapy, along with their roles in anti-tumor immunity.<h4>Methods</h4>Peripheral blood from 61 patients with advanced BC was analyzed by flow cytometry for immunophenotype before treatment. The gene discussed is CD28; the disease is breast cancer.