Although the third-generation EGFR-TKI osimertinib has demonstrated potent CNS efficacy with an intracranial PFS of 39.7 in T790M-positive NSCLC patients with BMs (40), once tumors have progressed and acquired resistance to the drug, the prognosis will be poor. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.