Importance Physical biomarkers for stratifying patients with lung cancer into subtypes suggestive of outcomes are underexplored. Objective To investigate the clinical utility of respiratory sarcopenia for optimizing postoperative risk stratification in patients with non–small cell lung cancer (NSCLC). Design, Setting, and Participants This retrospective cohort study reviewed consecutive patients undergoing lobectomy and mediastinal lymph node dissection for NSCLC at 2 institutions in Tokyo, Japan, between 2009 and…