1. Patients ≥ 18 years of age with histologically, and radiographically confirmed non-metastatic ER-positive (defined as ≥30% of positive cells) and HER2-positive (defined as overexpression by immunohistochemistry (3+) or 2+ and positive by defined by fluorescence or dual in situ hybridization.) breast cancer with minimal tumor size over 2 cm (≥T2 lesion) to receive neoadjuvant chemotherapy recommended by the treating physician