['A predicted postoperative (ppo) forced expiratory volume in 1 second (FEV1%) or diffusing capacity of the lung for carbon monoxide (DLCO%) of <40% has traditionally been considered to convey a high risk of lobectomy owing to elevated postoperative morbidity and mortality. These recommendations, however, were largely derived from the pre-video-assisted thoracoscopic surgical (VATS) era. We hypothesized that VATS lobectomy would be associated with acceptable morbidity and mortality at ppoFEV1% and ppoDLCO% values\xa0<\xa040%.', 'PpoFEV1% and ppoDLCO% were calculated for patients undergoing open or VATS lobectomy for lung cancer in the Society of Thoracic Surgeons General Thoracic database from 2009 to 2011. Univariate comparisons, multivariate analyses, and 1:1 propensity matching were performed.', 'A total of 13,376 patients underwent lobectomy (50.9% open, 49.1% VATS). A decreased ppoFEV1% and ppoDLCO% were each independent predictors for both cardiopulmonary complications and mortality in the open group (all P ≤ .008). In the VATS group, ppoFEV1% was an independent predictor of complications (P\xa0=\xa0.001) but not mortality (P\xa0=\xa0.77), and ppoDLCO% was an independent predictor of complications (P\xa0=\xa0.046) and mortality (P\xa0=\xa0.008). With decreasing ppoFEV1% or ppoDLCO%, complications and mortality increased at a greater rate in the open lobectomy than in a propensity-matched VATS group (n\xa0=\xa04215 each). For patients with ppoFEV1%\xa0<\xa040%, mortality was greater in the open (4.8%) than in the matched VATS group (0.7%, P\xa0=\xa0.003). Similar results were seen for ppoDLCO%\xa0<\xa040% (5.2% open, 2.0% VATS, P\xa0=\xa0.003). The rate of complications was significantly greater at ppoFEV1%\xa0<\xa040% in the open (21.9%) than in the matched VATS (12.8%, P\xa0=\xa0.005) group and similar results were seen with ppoDLCO%\xa0<\xa040% (14.9% open, 10.4% VATS, P\xa0=\xa0.016).'] Is thoracoscopic lobectomy associated with acceptable morbidity and mortality in patients with predicted postoperative forced expiratory volume in 1 second or diffusing capacity for carbon monoxide less than 40 % of normal?