Mutated-EGFRs were found in 186 (48.4%) of the 384 eligible patients (Figure 1), including an in-frame deletion in exon 19 (n = 79), a point mutation (L858R) in exon 21 (n = 97), and uncommon mutations (n = 10, 3 with an exon 18 point mutation, 6 with an exon 20 mutation, and 1 with an exon 18 and 20 mutation). The median OS of the mutated and WT patients was 20.6 months and 7.8 months, respectively (P < 0.001). The majority of the enrolled patients with stage IIIB-IV disease received cytotoxic chemotherapy and some received EGFR-TKIs (the first-generation) as the 1st-line care during the study period (Supplementary Materials and Methods). Of the 384 patients, 150 (39.1%) experienced BM, including 87 with BM at the diagnosis of their lung cancer and 63 with SBM during the follow-up period. Of 150 BM patients, 96 (64%) had mutated-EGFR and 54 had WT-EGFR.