EGFR and non-small cell lung carcinoma: For the first-generation of EGFR-TKI, gefitinib alone demonstrated an intracranial response rate of 87.8% (according to RECIST) for patients with EGFR-mutant advanced NSCLC and brain metastasis in the first-line setting.19 With more and more preclinical studies showing that second- and third-generation EGFR-TKIs had the more potent ability of CNS concentration and penetration rate, the activity of second- and third-generation EGFR-TKIs was further explored in the prospective or retrospective studies.