Until recently, the first line treatment of metastatic Non Small Cell Lung Cancer (NSCLC) was a platine-based chemotherapy. It has been changed by the discovery of EGFR (Epidermal Growth Factor Receptor) mutations and associated treatment with Tyrosine Kinase Inhibitor (TKI) of EGFR. The superiority of EGFR TKI over chemotherapy for EGFR mutated patients has been proved in several phase III trials with gefitinib, erlotinib or afatinib.