Dr. David Ryan has served as the chief of hematology/oncology and clinical director of Mass General Cancer Center since 2012. With a career dedicated to gastrointestinal malignancies, his expertise extends to designing and conducting clinical trials for patients with gastrointestinal cancers.?He is the Shelby Memorial Professor of Medicine at Harvard Medical School.

Dr. Ryan's contributions have earned him recognition on national committees, including clinical task forces for the National Cancer Institute, the National Comprehensive Cancer Network, and the American Society of Clinical Oncology. He obtained his MD from Columbia University College of Physicians & Surgeons. He completed residency in Internal Medicine at Columbia-Presbyterian Medical Center and fellowship in Hematology-Oncology at the combined Brigham and Women's Hospital/Massachusetts General Hospital/Dana-Farber Cancer Institute program. He has published over 100 articles in peer review journals, reviews, book chapters and editorials.