Currently, the combination of docetaxel, trastuzumab, and pertuzumab is the standard first-line treatment for HER2-positive metastatic breast cancer (MBC), but still, 60% of patients experience disease progression after 2 years of treatment. The second-line treatment standards include DS-8201, T-DM1, TKIs, etc., but these options still have their limitations and do not fully meet clinical treatment needs. Therefore, the team led by Professor Jian Liu from Fujian Provincial Tumor Hospital explored a second-line treatment regimen combining pyrotinib with inetetamab(the "Chinese Dual Target") + vinorelbine. The research results were included in the 2023 SABCS conference (Abstract number: PO1-04-05). Tumor Outlook invited Professor Jian Liu to introduce this study