One retrospective study suggested that a higher proportion of advanced mutated-EGFR NSCLC patients died of CNS metastases than did WT-EGFR patients (44.8% vs. 8.3%, P < 0.001) . Our findings that several factors contributed to SBM in NSCLC may be helpful in better understanding SBM occurrence and in clinical practice. Stage IIIB-IV NSCLC patients without BM at the time of lung cancer diagnosis were classified into subgroups by age and EGFR mutation status, and their cumulative incidences of SBM varied widely from 10.9 % (11/101) to 58.1% (18/31) (Figure 4), which indicates that NSCLC patients with mutated-EGFRs may require a higher frequency of brain imaging assessments than those with WT-EGFR to facilitate earlier BM detection, especially in the subgroup characterized by younger age and mutated-EGFRs (HR = 6.57, 95% CI = 3.17-13.70, P < 0.001).