ERBB2 and breast cancer: The HR-low/HER2-negative BC group had a lower 3-year EFS than the TNBC group (66.50% vs. 75.03%), and the patients with non-pCR from the HR-low/HER2-negative BC and TNBC groups showed an inferior 3-year EFS to that of the patients with pCR from the two groups (HR-low/HER2-negative BC with pCR and non-pCR: 94.74% vs. 57.39%; TNBC with pCR and non-pCR: 89.70% vs. 69.73%) (Figure 3B).