Although results from early phase II trials of trastuzumab as a treatment for HER2-mutant NSCLC have not shown any advantage for most patients, subsequent clinical trials have reported objective responses to afatinib (10, 11), poziotinib (12, 13), dacomitinib (14), neratinib plus temsirolimus (15), trastuzumab (16), trastuzumab emtansine (T-DM1) (17), and pyrotinib (18) in patients with HER2-mutant lung cancers (8). The gene discussed is ERBB2; the disease is lung cancer.