Combined action of EGFR tyrosine kinase inhibitors and whole-brain radiotherapy on EGFR-mutated non-small-cell lung cancer patients with brain metastasis

BACKGROUND: Lung cancer is the most common type of cancer to spread to the brain (brain metastasis [BM]). This study assessed the effect of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in combination with whole-brain radiotherapy (WBRT) on EGFR-mutant non-small-cell lung cancer (NSCLC) patients with BM. PATIENTS AND METHODS: Thirty-nine patients, who had receieved different EGFR TKIs plus 30 Gy WBRT until disease progression, were retrospectively analyzed between 2010 and 2014. Treatment response was evaluated and survival data were collected and analyzed. RESULTS: Among the 39 patients, 18 had an EGFR exon 19 deletion and 21 had an EGFR exon 21 point mutation. After therapy, 19 (48.7%) patients had complete remission, 12 (30.8%) had partial remission, and eight (20.5%) had stable disease in the intracranial lesions. Besides, there was no single case of complete remission, 21 (53.8%) had partial remission, and 18 (46.2%) had stable disease of the extracranial lesions. The median progression-free survival (PFS) of intracranial lesions and extracranial lesions was 18 and 12 months, respectively. The median overall survival (OS) was 26 months. The univariate analysis showed that graded prognostic assessment (P=0.006) and Karnofsky Performance Scale (P=0.045) were associated with intracranial progression-free survival (iPFS), while recursive partitioning analysis (P=0.049) was associated with OS of patients. CONCLUSION: EGFR TKIs plus concomitant WBRT controlled intracranial lesions of lung cancer metastasis and significantly improved OS of patients. Further studies will be needed to confirm whether this combination treatment could be used as a standard therapy for EGFR-mutated NSCLC patients with BM.