Surgical risk evaluation of lung cancer in COPD patients - A cohort observational study

Abstract

Coexistence between pulmonary cancer and chronic obstructive pulmonary disease (COPD) is frequent and is anticipated to be lead to high worldwide mortality in the next decades. The most powerful therapeutic approach for non-small cell lung carcinoma is lung surgical resection. However, in COPD patients, this approach bears a higher mortality and morbidity risk, thus requiring an accurate pre-operatory evaluation of the surgical risk comprising a clinical and functional assessment at rest, as well as a cardiopulmonary exercise test. In this observational study, factors associated with cardiopulmonary complications within 30 days after tumor resection surgery were investigated in a cohort of patients with COPD and lung cancer assigned to perform a cardiopulmonary exercise test. This study included 50 patients (46 men, 92.0%) with a mean age of 64.7 years old (standard deviation 7.9), forced expiratory volume in the first second (FEV1) of 61.8% (SD 19.0%) and carbon monoxide diffusing capacity (DLCO) of 46.0% (SD 14.8%). Complications were observed in eighteen patients (36.0%) including 2 deaths (4.0%). Peak oxygen uptake (VO2peak) expressed in percentage of the predicted value was the only parameter showing a statistically significant difference between the groups with and without complications (p=0.027). The best value of VO2peak to discriminate complications occurrence was 61.0%. This study highlights the relevance of the cardiopulmonary exercise test in the risk assessment of pulmonary resection surgery in patients with COPD. The VO2peak (percentage of predicted value) is shown to be associated with complications within 30 days after surgery.

Keywords: Cardiopulmonary exercise testing; Chronic obstructive pulmonary disease; Lung cancer; Postoperative complications.