Several advanced clinical trials have demonstrated that EGFR tyrosine kinase inhibitors (TKIs), including gefitinib,5,6 the first or second EGFR TKIs, and osimertinib, a third generation EGFR-TKI,7 confer progression-free survival (PFS) benefit in patients with NSCLC harboring EGFR mutation. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.