Prognostic value of preoperative exercise capacity in patients undergoing thoracoscopic lobectomy for non-small cell lung cancer

Abstract

ObjectivesWhether or not the preoperative exercise capacity, as assessed by 6-min walk test, influences the survival of patients undergoing thoracoscopic lobectomy for lung cancer is unclear. We therefore investigated the prognostic value of the 6-min walk distance in this population. Materials and methodsThis prospective cohort study was conducted between 2005 and 2013. We studied 224 consecutive subjects with stage I-II non-small cell lung cancer who underwent thoracoscopic lobectomy. Survival was calculated by the Kaplan-Meier method. The log-rank test was used to assess the survival rate. Cox proportional hazards models were used to estimate the risk of 5-year all-cause mortality based on the preoperative 6-min walk distance with adjustment for other prognostic factors, including the age, performance status, postoperative cardiopulmonary complication, and pathological stage. ResultsThe median follow-up period was 60.8 months. During this period, 38 deaths were recorded. The 5-year overall survival rate of the subjects with a preoperative 6-min walk distance of <400 m were significantly lower than those with a 6-min walk distance of ≥400 m (65.3% vs. 88.0%; p < 0.001). A multivariate analysis showed that the 6-min walk distance was significantly associated with the overall survival after adjusting for the age and pathologic stage (hazard ratio, 2.40; 95% confidence interval, 1.20–4.79), but it did not provide additional prognostic value beyond the performance status. ConclusionThe preoperative 6-min walk distance may be useful as an additional prognostic factor for patients at an increased risk of mortality after thoracoscopic lobectomy for stage I-II non-small cell lung cancer.