However, 50%–60% of patients with EGFR‐mutated LC initially treated with first‐ and second‐generation EGFR tyrosine kinase inhibitors (TKIs) may develop the T790M resistance mutation in exon 20, which remains sensitive to the third‐generation TKI, Osimertinib [17]. The gene discussed is EGFR; the disease is laryngotracheoesophageal cleft.