The DESTINY-Breast trials established trastuzumab deruxtecan (T-DXd) as a treatment significantly improving outcomes in human epidermal growth factor receptor 2 (HER2)-positive and HER2-low metastatic breast cancer (MBC). However, real-world effectiveness is susceptible to confounding factors. This multicenter, real-world study aims to systematically evaluate the efficacy and safety of T-DXd in patients with HER2-positive and HER2-low MBC. Key clinicopathological parameters were to be integrated to develop an individualized prognostic prediction model, facilitating precision medicine implementation in clinical practice.
