ERBB2 and breast cancer: Recently, T-DXd has been approved for patients with HER2-positive unresectable or metastatic BC, who received at least two prior anti-HER2-directed treatments, based on the results of the DESTINY-Breast01 (DB01) and DESTINY-Breast02 (DB02) trials [34,35], which have shown an unprecedented and dramatic patients’ survival improvement, even in a heavily pre-treated and refractory disease.