MKI67 and neoplasm: After excluding menopausal status, tumor stage, lymph node status, vascular invasion, tumor histological grade, pathological treatment response, the number of lymph nodes after NAC, NAC regimen, the number of NAC cycles, and HER2 and Ki-67 status, changes in HR status occurred more frequently in patients <35 years of age or with a slight therapeutic response (grade 1) (Table 2).