Long-term Outcomes After Lung Cancer Resection in Smokers: Analysis of the National Lung Screening Trial

Abstract

Background: Smoking is a known risk factor for perioperative complications after lung resection; however, little data exists looking at the impact of smoking status (current versus former) on long-term oncologic outcomes after lung cancer surgery. We sought to compare overall survival (OS), progression-free survival (PFS), and cancer-specific mortality (CSM) in current and former smokers using data from the National Lung Screening Trial (NLST). Additionally, we performed subset analysis in current smokers in order to evaluate the effect of modern surgical techniques on long-term outcomes.

Methods: Patients with clinical stage IA or IB NSCLC who underwent upfront resection within 180 days of diagnosis were identified in the NLST database. Cox proportional hazard regression models were used to assess differences in patient and treatment characteristics with respect to OS and PFS, with a cause-specific hazard model used for CSM.

Results: A total of 593 patients were included in the study (269 former smokers, 324 current smokers). Lobar resection (LR) was performed more often than sublobar resection (SLR) (481 vs. 112), and thoracotomy was performed more often than thoracoscopy (482 vs. 86). Comparison of current versus former smokers showed no difference in OS or PFS after resection. Higher CSM was seen in current smokers (p = 0.049). Subset analysis of current smokers revealed no difference in OS or PFS between sub-lobar and lobar resection or thoracotomy and thoracoscopy. Although higher CSM was associated with thoracoscopy versus thoracotomy in this group, this finding was limited by a relatively small thoracoscopy sample size of 44 patients (p = 0.026).

Conclusion: Our analysis of the NLST database shows no significant difference in OS and PFS when comparing current and former smokers undergoing resection for stage I NSCLC. Active smoking status was associated with higher CSM. Subset analysis of current smokers showed no difference in OS or PFS between sub-lobar and lobar resection or thoracotomy and thoracoscopy. Higher CSM was seen in current smokers who underwent thoracoscopy compared to thoracotomy; however, this finding was limited by a small sample size.