Kaplan–Meier curves of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) progression-free survival (PFS) for EGFR mutant lung adenocarcinoma patients stratified into predefined age categories: ≤50, 51–60, 61–70, 71–80 and >80 years. Kaplan–Meier curves of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) progression-free survival (PFS) for EGFR mutant lung adenocarcinoma patients stratified into predefined age categories: ≤50, 51–60, 61–70, 71–80 and >80 years. The difference was statistically significant (p=0.033, log-rank test). Shang-Gin Wu et al. ERJ Open Res 2017;3:00092-2016 ©2017 by European Respiratory Society