EGFR and non-small cell lung carcinoma: Locally advanced (stage III) or metastatic NSCLC patients with activating mutations in the EGFR gene have exhibited a dramatic response to EGFR tyrosine kinase inhibitors (EGFR-TKI), such as gefitinib and erlotinib, since these activating mutations, including exon 19 deletions and the L858R point mutation in exon 21, are recognized as markers of EGFR-TKI therapy sensitivity in NSCLC (26).