Dr. Justin Gainor

Dr. Justin F. Gainor, MD, is a leading thoracic oncologist specializing in lung cancers and rare thoracic tumors, with a focus on targeted therapies and immuno-oncology. He serves as Director of the Center for Thoracic Cancers at Massachusetts General Hospital (MGH) Cancer Center and Associate Professor of Medicine at Harvard Medical School. Dr. Gainor earned his medical degree from Harvard Medical School, completed his residency in internal medicine at Massachusetts General Hospital, and trained as a fellow in hematology/oncology at Dana-Farber/Partners CancerCare. He is board-certified in Internal Medicine and Medical Oncology.

Dr. Gainor’s research focuses on the biology of oncogenic drivers in lung cancer, including ALK, ROS1, RET, and KRAS, and the mechanisms of resistance to targeted therapies. He has also played a critical role in the development of immunotherapy for lung cancer, leading investigator-initiated and multicenter trials that integrate novel immunotherapeutics with targeted agents. His publications in New England Journal of Medicine, Journal of Clinical Oncology, and other leading journals have significantly shaped treatment paradigms.

In addition to his clinical and research leadership, Dr. Gainor is a dedicated educator, mentoring oncology trainees and contributing to national working groups on lung cancer. Through his translational research and clinical innovation, Dr. Justin Gainor continues to expand therapeutic options and improve outcomes for patients with thoracic malignancies.