In our study, it was found patients having both EGFR-mutant and ERBB2 amplified NSCLC treated with first-generation EGFR TKIs reached a median PFS of 4.2 months, which was significantly shorter than that of patients with EGFR mutations alone (4.2 vs 10.5 months; HR = 2.5, 95% CI, 1.03–6.09; p = 0.0005). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.