Comment on: European Respiratory Society and European Society of Thoracic Surgeons clinical practice guideline on fitness for curative intent treatment of lung cancer

Extract We read with great interest the recent European Respiratory Society and European Society of Thoracic Surgeons clinical practice guidelines on fitness for curative intent treatment of lung cancer [1]. We acknowledge the tremendous work of the task force in reviewing the literature and producing such a succinct and clinically useful document. As researchers in the field of preoperative functional evaluation, we particularly welcome the increased emphasis on ventilatory efficiency (minute ventilation/carbon dioxide output slope) during cardiopulmonary exercise testing (CPET) compared with the 2009 version [2], and the proposed threshold of >40 to define high risk.