Both are indicated for first-line use in patients with metastatic NSCLC carrying common EGFR sensitizing mutations in exons 18–21, such as the L858R missense mutation in exon 21 or exon 19 deletions, together accounting for more than 90% of exon 18–21 mutations in these patients (31, 105, 106). This evidence concerns the gene EGFR and non-small cell lung carcinoma.