Six minute walking test and carbon monoxide diffusing capacity for non-small cell lung cancer: easy performed tests in every day practice

Abstract

Background: Several studies have demonstrated that reduced lung function is a significant risk factor for lung cancer and increased surgical risk in patients with operable stages of lung cancer. The aim of the study was to perform pulmonary function tests and investigate which is a favorable respiratory function test for overall survival between lung cancer stages.

Methods: Lung function tests were performed to lung cancer patients with non-small cell lung cancer of stage I, II, III and IV (241 patients in total). They had the last follow-up consecutively between December 2006 and July 2008. The staging was decided according to the sixth edition of TNM classification of NSCLC. The Forced Expiratory Volume in 1sec (FEV1), Forced Vital Capacity (FVC) and Carbon Monoxide Diffusing Capacity (DLCO) were measured according to American Thoracic Society/European Respiratory Society guidelines. The 6 Minute Walking Test (6MWT) was measured according to the American Thoracic Society.

Results: There was a significant association of the DLCO upon diagnosis and overall survival for stage II (P<0.007) and IV (P<0.003). Furthermore, there was a significant association between 6MWT and overall survival for stage III (P<0.001) and stage IV (P<0.010).

Conclusions: The significance for each lung function test is different among the stages of NSCLC. DLCO and 6MWT upon admission are the most valuable prognostic factors for overall survival of NSCLC.

Keywords: 6MWT; DLCO; FEV1; FVC; NSCLC.

Figure 1

Forced Exiratory Volume in 1sec (FEV₁), Forced Vital Capacity (FVC), Carbon Monoxide Diffusing Capacity (DLCO) and 6 Minute Walking Test (6MWT) measurements for all stages. (In the Vertical Axis the measurement values are presented and in the horizontal axis the time of the measurement) (y axis. % pred; x axis. time of evaluation).

Figure 2

A. DLCO1 upon diagnosis and overall survival for stage II (P<0.007); B. DLCO1 upon diagnosis and overall survival for IV (P<0.003); C.6MWT1 upon diagnosis and overall survival for stage III (P<0.000); D. 6MWT1 upon diagnosis and overall survival stage IV (P<0.010). (y axis. Days of survival; x axis. pulmonary function test).