Recently, the DESTINY-Breast03 data showed improved outcomes with Trastuzumab deruxtecan (Enhertu) compared to Trastuzumab emtansine (T-DM1), with a longer duration of progression-free survival among patients with HER2-positive breast cancers (28.8 months vs. 6.8 months) [48]. This evidence concerns the gene ERBB2 and breast cancer.