Gefitinib was the first EGFR TKI receiving regulatory approval for EGFR-mutated NSCLC patients after the publication of the results of the IPASS (Iressa Pan-Asia Study) trial, reporting a significant advantage in terms of PFS and ORR for first-line Gefitinib versus Carboplatin/Paclitaxel [63]. This evidence concerns the gene EGFR and non-small cell lung carcinoma.