Although chemotherapy and HER2-targeted therapies have shown inconsistent results in patients with HER2-positive NSCLC [43,70,71], the phase II DESTINY-Lung01 and DESTINY-Lung02 trials led to the approval of trastuzumab deruxtecan (T-DXd) in this subgroup, demonstrating significant clinical benefit [72,73]. The gene discussed is ERBB2; the disease is non-small cell lung carcinoma.