EGFR and non-small cell lung carcinoma: In 2015, gefitinib, one of the first-generation EGFR tyrosine kinase inhibitors (EGFR-TKIs), was approved by the United States Food and Drug Administration (USFDA) as a first-line treatment for metastatic NSCLC patients with activating EGFR mutations, resulting a longer progression-free survival (PFS) compared to standard cytotoxic chemotherapy (Gridelli et al., 2011; Douillard et al., 2014).