Hospital case-volume and mortality after lung cancer surgery: A population-based retrospective cohort study

•Recent advances in lung cancer treatment warrants reassessment of case-volume effect.•This study reassessed the case-volume effect using the most recent national data.•Centers with > 200 cases/year of lung cancer surgery showed lower mortality. Recent advances in lung cancer treatment warrants reassessment of the volume-outcome association in lung cancer surgery. This study reassessed the relationship between surgical case-volume and both in-hospital and long-term mortality after lung cancer surgery using a current database to reflect recent advances. Using the database of the National Health Insurance Service in Korea, data of all adult patients who underwent lung cancer surgery in Korea between 2005 and 2019 were obtained. Hospitals were categorized by the annual number of lung cancer surgeries. Risk-adjusted in-hospital and 1, 3, 5-year mortality after surgery were assessed. A total of 84,194 lung cancer surgeries were performed in 163 centers during the study period. High-volume centers were defined as > 200 cases/year, medium-volume centers as 60–200 cases/year, and low-volume centers as