ER+/HER2+ metastatic breast cancer is a special subtype of HER2+ breast cancer. General guidelines recommend chemotherapy combined with HER2-targeted therapy for this subtype of patients. However, for the highly selected patients with ER- positive/HER2-positive ABC, ET + anti-HER2 therapy could be chosen as first-line therapy. And Pyrotinib is an oral tyrosine kinase inhibitor targeting both HER-1 and HER-2 receptors. Therefore this study is planned to enroll 86 patients with HER2-positive, ER-positive metastatic breast cancer receiving first-line treatment with pyrotinib and letrozole. The main purpose was to evaluate the efficacy and safety of pyrotinib combined with letrozole in patients with HER2-positive, ER-positive metastatic breast cancer.
This is a prospective, single-arm, multi-center clinical study of pyrotinib in combination With letrozole in patients With HER2-Positive, ER-Positive metastatic breast cancer. Our aim was to explore the efficacy and safety of pyrotinib combined with letrozole in patients with HER2-positive, ER-positive metastatic breast cancer.