ESR1 and breast cancer: ,7 According to clinical guidelines,1 current NAT mainly involve polychemotherapy with an anthracycline plus taxane backbone (e.g., AC-T) for triple-negative patients, chemotherapy combined with HER2 antibodies (specifically trastuzumab and pertuzumab) for HER2+ tumors, and neoadjuvant chemotherapy or endocrine therapy (e.g., tamoxifen) for ER/PR+ breast cancer.