Is EGFR gene mutation testing necessary in smokers with non-small cell lung cancer?

Abstract

Abstract Objective Previous studies have proven that cumulative smoking dose predicts the prevalence of epidermal growth factor receptor (EGFR) mutations. The aim of this study was to investigate the relationship between smoking-related factors and EGFR mutation status. Methods Samples were collected from 195 smokers with non-small cell lung cancer (NSCLC) who underwent surgical resection and the presence of EGFR mutations (exons 19 and 21) were determined by real-time polymerase chain reaction (RT-PCR). Results EGFR gene mutations were present in 33 (16.9%) patients who were smokers; the patients were divided into three groups according to the smoking index (SI). The incidence of EGFR mutations decreased from 38.9% in mild smokers to 8.1% in severe smokers (P = 0.001). Compared to daily smoking dose (P = 0.547), initial smoking age (P = 0.085) and duration of smoking history had a larger effect on EGFR mutation status (P = 0.002). Conclusion Although there is a decrease in the incidence of mutations with increasing SI, there were still around 17% of smokers with NSCLC that harbored EGFR mutations, so it is necessary to test for EGFR mutation status in smokers with NSCLC.