Adenocarcinoma is the major histological type of non-small cell lung cancer (NSCLC), but the standard care for patients with metastatic NSCLC has shifted from traditional platinum-based doublets to precision targeted therapy to the driver genes with mutations, such as the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), ROS-1, and BRAF (3, 4). The gene discussed is EGFR; the disease is adenocarcinoma.