The impact of smoking status on radiologic tumor progression patterns and response to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors in lung adenocarcinoma with activating EGFR mutations.

BACKGROUND: The aim of this study was to evaluate the impact of smoking on the treatment outcome of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) in patients with EGFR-mutant lung adenocarcinoma, with consideration of other factors including radiologic tumor progression pattern according to patient smoking status.
METHODS: A total of 224 patients with EGFR mutant lung adenocarcinomas that were treated with EGFR-TKIs were retrospectively reviewed. Radiologic tumor progression pattern and treatment outcomes were evaluated according to smoking history.
RESULTS: There were no significant differences in radiologic tumor progression pattern based on smoking status. There were no significant differences in survival between never-smokers and smokers or among never-, former-, and current-smokers, but there was a trend of shorter progression free survival (PFS) and poorer overall survival (OS) in smokers compared with never-smokers. In multivariate analysis, long-term smokers had shorter PFS and poorer OS than those who had never smoked.
CONCLUSIONS: A history of smoking had no significant effect on radiologic tumor progression pattern; however, smoking history is a negative predictive factor of survival in patients with EGFR-mutant lung adenocarcinoma undergoing EGFR-TKI therapy.