EGFR and non-small cell lung carcinoma: Treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) such as Erlotinib or Gefitinib helps to prolong the progression-free survival (PFS) time, increase the response rate, and minimize the side effects compared to standard chemotherapy treatment for non-small cell lung cancer (NSCLC) patients who carried the activating EGFR mutations (deletions in exon 19—E19del, and L858R substitution mutation in exon 21) [1, 2].