Tracy L. Breen, MD, FACP

President and Chief Medical Officer, Mount Sinai Morningside and Mount Sinai West

Tracy L. Breen, MD, FACP, is President and Chief Medical Officer of Mount Sinai Morningside and Mount Sinai West, and Professor of Medicine (Endocrinology, Diabetes and Bone Disease) at the Icahn School of Medicine at Mount Sinai. As president, she works in close partnership with leaders across the Health System to further implement strategic priorities at these two hospitals.

Dr. Breen has played a key role at Mount Sinai’s West Side hospitals for more than a decade. She became Chief Medical Officer for Mount Sinai West in 2014 and added Mount Sinai Morningside to her responsibilities in 2023. She continues to serve in those roles, bringing vision, innovation, and a steadfast commitment to improving patient care and safety.

Dr. Breen first joined Mount Sinai in 2005 as a faculty member in endocrinology at The Mount Sinai Hospital. She became Clinical Director of the Mount Sinai Diabetes Center a year later and developed the hospital’s first comprehensive inpatient diabetes service, expanded nutritional and educational offerings to patients, and partnered with community-based programs to support diabetes prevention.

Dr. Breen left Mount Sinai in 2011 for a position at Northwell, returning to the Health System in 2014. She is a Fellow of the American College of Physicians, a member of the American College of Healthcare Executives, and a faculty mentor for Stanford University’s Master of Science in Clinical Informatics Management program. Dr. Breen served as Chief Resident at New York University, where she earned her MD and completed an internal medicine residency. She completed a National Institutes of Health-funded research fellowship in endocrinology at Columbia, where her work focused on the neuroendocrine mechanisms of energy homeostasis. During her tenure at Mount Sinai, Dr. Breen has taught medical students, residents, and fellows, and she continues to mentor and develop faculty members and advanced practice providers throughout the Health System.