Considering the fact that the EGFR-T790M mutation occurs in a large population (60–70%) of EGFR-mutated lung cancer patients who acquired resistance to first-generation EGFR-TKIs gefitinib and erlotinib10, these observations suggest that mechanisms of osimertinib resistance are much more diverse, and thus acquired osimertinib resistance may be harder to be controlled. This evidence concerns the gene EGFR and lung cancer.