In recent studies, afatinib, a second-generation inhibitor, showed superior outcomes, when compared to the first-generation of EGFR-tyrosine kinase inhibitors (TKIs), such as erlotinib and gefitinib, in patients with advanced non-small cell lung cancer (NSCLC) harboring mutations of epidermal growth factor receptor (EGFR). This evidence concerns the gene EGFR and non-small cell lung carcinoma.