EGFR and non-small cell lung carcinoma: A related study by Schmid et al. evaluated the efficacy of osimertinib in advanced non-small cell lung cancer, in which the disease control rate was 85% in 27 patients with confirmed positive EGFR T790 M mutations, and further analysis of the efficacy of osimertinib in patients with T790M-positive brain metastases revealed no significant difference in the comparison with those without brain metastases, indicating that osimertinib is equally effective in patients with advanced non-small cell lung cancer with brain metastases [18].