The Prognostic Impact of Cigarette Smoking on Patients with Non-small Cell Lung Cancer

Introduction: The purposes of this study are to investigate the association between cigarette smoking and clinicopathological characteristics of patients with non-small cell lung cancer (NSCLC) and to evaluate its significance as a predictor of recurrence after resection. Methods: A total of 2295 consecutive patients with NSCLC underwent complete resection with systematic node dissection between August 1992 and December 2006 at the National Cancer Center Hospital East. Results: A statistically significant difference in the 5-year overall survival rate was observed between never and ever smokers in patients with stage I (92% and 76%, respectively, p < 0.001) NSCLC, whereas no difference was observed in stage II (57% and 52%, respectively, p = 0.739) and stage III (30% and 33%, respectively, p = 0.897). In patients with stage I NSCLC, 5-year recurrence-free proportions (RFPs) for never and ever smokers were 89% and 80%, respectively (p < 0.001). In contrast, the 5-year RFPs for never smokers were lower than those for ever smokers in stage II (44% and 60%, respectively, p = 0.049) and stage III (17% and 31%, respectively, p = 0.004). In stage I patients, significant difference in 5-year RFP was observed between never and ever smokers (89% and 83%, respectively) in patients with adenocarcinoma, but not in patients with nonadenocarcinoma (82% and 76%, respectively). Conclusions: Smoking history showed different impact on postoperative recurrence in patients with NSCLC between stage I and stages II and III, and depending on histology in stage I patients. Disease stages should be considered while evaluating smoking history as a predictor of recurrence.