Common driver mutations and programmed death-ligand 1 expression in advanced non-small cell lung cancer in smokers and never smokers.

Background: In non-small cell lung cancer (NSCLC), there may be a relationship between programmed death-ligand 1 (PD-L1) expression, driver mutations and cigarette smoking.

Methods: In this single-center retrospective study, the relationship between common driver mutations (EGFR mutation and ALK rearrangement) and PD-L1 expression in advanced NSCLC according to the patients' smoking history was examined. Light, moderate and heavy smokers had smoked < 20, 20-39, and ≥ 40 pack-years, respectively.