Prognostic significance of functional capacity and exercise behavior in patients with metastatic non-small cell lung cancer.

BACKGROUND: To investigate the prognostic importance of functional capacity and exercise behavior in patients with metastatic non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Using a prospective design, 118 consecutive participants with histologically confirmed metastatic (inoperable) NSCLC and Eastern Cooperative Oncology group (ECOG) 0-3 completed a six-minute walk test to assess functional capacity and questionnaire that assessed self-reported exercise behavior. Cox proportional models were used to estimate the risk of all-cause mortality according to six-minute walk distance (6MWD) (<358.5m, 358.5-450 m, ≥450 m) and exercise behavior (MET-hrswk(-1)) categories with adjustment for important covariates. RESULTS: Median follow-up was 26.6 months; 77 deaths were reported during this period. Functional capacity was an independent predictor of survival (P(trend)=0.003) and added incremental prognostic value beyond that provided by PS plus other traditional markers of prognosis (P(trend)=0.025). Compared with patients achieving a 6MWD <358.5m, the adjusted hazard ratio (HR) for all-cause mortality was 0.61 (95% CI, 0.34-1.07) for a 6MWD of 358.5-450 m, and 0.48 (95% CI, 0.24-0.93) for a 6MWD >450 m. In unadjusted analysis, there was a borderline significant effect of exercise behavior on survival (p=0.052). Median survival was 12.89 months (95% CI, 9.11-21.05 months) for those reporting <9MET-hrswk(-1) compared with 25.63 months (95% CI, 11.28 to ∞ months) for those reporting ≥9MET-hrswk(-1). CONCLUSIONS: Functional capacity is a strong independent predictor of survival in advanced NSCLC that adds to the prediction of survival beyond traditional risk factors. This parameter may improve risk stratification and prognostication in NSCLC.

Duke Scholars

Author Margaret Gradison Family Medicine and Community Health, Family Medicine

Author James Emmett Herndon II Biostatistics & Bioinformatics, Division of Biostatistics