Preoperative Maximum Oxygen Consumption Is associated with Prognosis After Pulmonary Resection in Stage I Non-small Cell Lung Cancer

Background: The objective of this investigation was to evaluate whether maximum oxygen consumption (VO2max) is a reliable prognostic factor after lung resection for pathologic stage I non-small cell lung cancer (NSCLC).

Methods: Observational analysis of 157 patients undergoing pulmonary lobectomy or segmentectomy for pathologic stage I (T1 or T2-N0 only) NSCLC, with preoperative measurement of Vo2max and complete follow-up (2006-2011). Survival was calculated by the Kaplan-Meier method. The log-rank test was used to assess differences in survival between groups. The relationships between survival and several baseline and clinical variables were determined by Cox multivariate analyses.

Results: The median follow-up time was 40 months. The average preoperative Vo2max was 16.1 mL/kg · min and 69% of predicted value. Sixty-two (40%) patients had a Vo2max below 60%. The median and 5-year overall survivals of patients with preoperative Vo2max above 60% were significantly longer than in those with Vo2max below 60% (median not reached vs 48 months: 73% vs 40%, p=0.0004). Cox regression model showed that an age older than 70 years (p=0.005, hazard ratio 2.3) and Vo2max below 60% (p=0.001, hazard ratio 2.4) were independent prognostic factors significantly associated with overall survival. Cancer-specific survival was also longer in patients with Vo2max above 60% (81% vs 61%, p=0.01).

Conclusions: Exercise tolerance may influence the physiologic outcomes associated with cancer that can potentially affect survival. Physical rehabilitation aimed at improving exercise tolerance can possibly improve the long-term prognosis after operations for lung cancer.