Following this, Zhang et al. retrospectively reviewed 43 Chinese EGFR mutant NSCLC patients with BM treated with gefitinib or erlotinib until extracranial lesion progression; an intracranial lesion ORR of 57% and PFS of 9.3 months was observed, with no statistically significant difference in OS between gefitinib versus erlotinib (45). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.