Abstract
OBJECTIVES: Smoking is a major lung cancer risk factor. Studies show that smoking after lung cancer diagnosis is associated with an increased risk of developing other cancers and shorter survival. The purpose of this study was to examine the association between postdiagnosis smoking cessation and survival in patients with advanced non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: A retrospective cohort study was conducted. Data were collected between January 2014 and December 2019 in three hospitals in Southern Taiwan. Patient data were collected from the hospitals' databases, and the correlation between smoking status and patient survival was analyzed using Kaplan-Meier curves and Cox proportional hazards regression modeling. RESULTS: A total of 681 patients with advanced NSCLC were included in this study. The numbers (percentage) of ex-smokers and current smokers were 334 (49%) and 347 (51%), respectively. More than half of the patients in this study continued to smoke postdiagnosis advanced NSCLC. Furthermore, ex-smokers had lower mortality risk, even though this was not statistically significant (P = 0.212). The results of this study suggest that older than 65 years, men, Eastern Cooperative Oncology Group performance score of 3 and higher, history of chronic disease, receive chemotherapy, and targeted therapy are correlated with and have predictive effects on advanced NSCLC survival. CONCLUSION: There is no significant difference between postdiagnosis smoking cessation and survival in patients with advanced NSCLC. The reason for this finding may be due to lower survival rates after diagnosis with advanced NSCLC, and the benefits of smoking cessation cannot be seen immediately.