Trastuzumab-deruxtecan (T-DXd), an ADC designed to target HER2, has already received approval for HER2-positive and HER2-low breast cancer (17, 18) and is being investigated for its efficacy in HER2-positive EC in the clinical trial DESTINY-PanTumor02 (ClinicalTrials.gov identifier: NCT04482309). The gene discussed is ERBB2; the disease is breast cancer.