Most recently, combination of osimertinib and gefitinib was demonstrated some efficacy in patients with C797S and T790M EGFR-mutated NSCLC, but the improvement is brief [19]; the activation of Src family kinases and focal adhesion kinase (FAK) was revealed to contribute to the resistance to afatinib, erlotinib and osimertinib in afatinib-resistant HCC827 cells, which lost the amplified, mutated EGFR genes [20]. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.