Trastuzumab Combined With Pertuzumab for Adjuvant Treatment of Breast Cancer After Neoadjuvant Therapy

Patients with HER-2 positive breast cancer who have poor outcomes after endocrinotherapy and standard chemotherapy can be significantly improved by the use of anti-HER-2 monoclonal antibody trastuzumab. In the current clinical practice of neoadjuvant therapy, trastuzumab combined with chemotherapy can significantly increase the pCR and improve the outcomes in patients. However, there seems to be no available treatment for patients who have no pCR and still have residual tumors except for sequential trastuzumab treatment for 1 year. Compared with trastuzumab, a HER-2 macromolecule inhibitor, pyrotinib has a different site of action and an increased EGFR target. Compared with lapatinib, a small molecule inhibitor of EGFR and HER-2, pyrotinib is an irreversible inhibitor, with the ability to achieve a better curative effect at a lower human plasma exposure level. This trial is designed to evaluate the effectiveness and safety of trastuzumab combined with pertuzumab followed by sequential pyrotinib treatment in non-pCR patients after neoadjuvant therapy.