Methods: This analytical retrospective observational study included 111 patients with early and locally advanced HER-2-positive breast cancer who initiated neoadjuvant treatment with an anthracycline-based scheme (four cycles of doxorubicin and cyclophosphamide, followed by four cycles of taxane, trastuzumab, and pertuzumab = AC-THP) and a non-anthracycline scheme (carboplatin, weekly paclitaxel, trastuzumab, and pertuzumab for six–nine cycles = TCbHP) at the National Cancer Institute in Colombia, between April 2020 and December 2024. Here, ERBB2 is linked to breast cancer.