Dr. Hahn is a dedicated clinician, having trained in both medical oncology and radiation oncology. Prior to joining the FDA, Dr. Hahn served as the chief medical executive at The University of Texas MD Anderson Cancer Center, a facility that cares for more than 140,000 patients a year. Before joining MD Anderson, he served as chair of the Radiation Oncology department at the University of Pennsylvania’s Perelman School of Medicine from 2005 to 2014.