ERBB2 and breast carcinoma: It is well known that compared with HR+ HER2− breast cancer, HER2+ or TNBC is more likely to achieve axillary nodal pCR [29, 30]; the axillary nodal pCR rate was approximately 20–25% in HR+ HER2− breast cancer and 40–90% in HER2+ or TNBC [31–33].