Unlike drug resistant mutations (Exon 20 T790M point mutation (T790M) and exon 20 insertion mutation (20-ins)), NSCLC harboring EGFRTKI sensitive mutations such as exon 19 deletion mutation (19-del) and exon 21 L858R point mutation (L858R) respond to EGFR-TKIs [14]. This evidence concerns the gene EGFR and non-small cell lung carcinoma.