The Importance of Brain Metastasis in EGFR Mutation Positive NSCLC Patients

Abstract

Introduction. Brain metastasis is a poor prognostic marker in lung cancer. However it is not known whether amongst patients with EGFR mutation those with brain metastases have a worse outcome. Methods. We compared the survival outcomes between EGFR mutation positive patients with and without brain metastases. In this retrospective analysis of prospective database of all metastatic lung cancer patients at our centre between July 2009 and December 2012, patients were treated with either combination chemotherapy or oral TKI. All patients with brain metastases received whole brain radiation. Kaplan Meier method was used for survival analysis and compared using log rank test. Results. 101 patients with EGFR mutated, metastatic lung cancer were studied. Fourteen had brain metastases and 87 did not. The common EGFR mutations were exon 19 deletion (61.3%) and exon 21 L858R mutation (28.7%). Overall response was 64% in extracranial metastasis group as compared to 50% in brain metastasis group. There was a significant worsening of median OS in the patients with brain metastases (11.6 months) compared with only extracranial metastases (18.7 months), P=0.029. Conclusion. Amongst patients with EGFR mutant NSCLC, the presence of brain metastases leads to a worse outcome as compared to patients with extracranial metastases alone.