ERBB2 and breast carcinoma: The Collaborative Trials in Neoadjuvant Breast Cancer group analyzing the pCR association with long-term outcome have found that the highest pCR was achieved in HER2-positive/HR-negative breast cancer (50.3%) after administration of trastuzumab followed by TNBC (33.6%) and by grade 3 HR-positive/HER2-negative breast cancer with a pCR rate of (16.2%) (1, 19).