Trastuzumab-deruxtecan (T-DXd) is an antibody-drug conjugate (ADC) composed of trastuzumab, a monoclonal antibody targeting HER2, linked to the cytotoxic agent deruxtecan via a chemical linker [1]. T-DXd has been increasingly used for treating various advanced human epidermal growth factor receptor 2 (HER2)-positive tumors, including breast cancer (BC) [2], gastric cancer [3], non-small cell lung cancer (NSCLC) [4], and colorectal cancer [5]. T-DXd has also shown clinical benefit in advanced HER…