Trastuzumab Combined With Pyrrolidine and Chemotherapy for Locally HER2 Positive Breast Cancer

"Pyrotinib is a small molecule, irreversible tyrosine kinase inhibitor with targets of epidermal growth factor receptor 1 (EGFR/HER1/ErbB1), human epidermal factor receptor 2 (HER2/ErbB2/Neu) and human epidermis Factor Receptor 4 (HER4/ErbB4).~As a new generation of anti-HER2 therapeutic targeted drugs, pirotinib covalently binds to the ATP binding sites of the kinase regions of EGFR, HER2 and HER4 in cells to prevent homogeneity and heterogeneity of EGFR, HER2 and HER4 in tumor cells Dimer formation, inhibiting its own phosphorylation, blocking the activation of downstream signaling pathways, thereby inhibiting tumor cell growth"