Survival of patients with brain metastases from non-small cell lung cancer harboring EGFR mutations treated with epidermal growth factor receptor tyrosine kinase inhibitors

Brain metastases (BM) is one of the most crucial distant metastases in patients with non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations. There is no consensus about which EGFR tyrosine kinase inhibitor (TKI) is most effective against BM in such patients. Here, we compared prognoses of patients with EGFR-TKI naïve EGFR-positive BM treated with erlotinib or gefitinib after BM diagnosis. Of 269 patients with NSCLC treated with EGFR-TKIs at a single institution, we reviewed medical records of 205 patients with documented EGFR mutations. Eleven patients were administered erlotinib, and 52 patients were administered gefitinib as the first-line EGFR-TKI treatment after diagnosis. We used propensity score matching to balance patient backgrounds between groups, and the log-rank test to compare survival curves. Patients with BM at the induction of chemotherapy had a poorer prognosis than those without BM [median overall survival (OS) 18.5 vs. 28.0 months]. Meanwhile, there was no significant difference in OS between those with or without BM at the initiation of EGFR-TKI treatment (20.3 vs. 23.8 months). Median OS of patients treated with erlotinib was not significantly longer than that of patients treated with gefitinib (25.0 vs. 18.1 months). The presence of BM at the initiation of EGFR-TKI treatment had no apparent effect on survival. Erlotinib was deemed more effective than gefitinib in preventing intracranial lesions and prolonging survival; however, prospective studies are needed to confirm these results.