Dr. Cohen completed a hematology/oncology fellowship at the University of Chicago, where he was named chief fellow. He completed residencies in family medicine at the University of Toronto and in internal medicine at Albert Einstein College of Medicine. Dr. Cohen earned his medical degree at University of Toronto. He is board certified in medical oncology, and a fellow of the Royal College of Physicians and Surgeons of Canada (FRCPSC) and the American Society of Clinical Oncology (FASCO). Prior to joining UC San Diego Health in 2014, Dr. Cohen was co-director of the Head and Neck Cancer Program at the University of Chicago Comprehensive Cancer Center As a physician-scientist, Dr Cohen also leads a laboratory that studies novel cancer treatments, including immunotherapy, and has made major contributions in understanding how targeted cancer therapies work. Much of his work has focused on squamous cell carcinomas and cancers of the thyroid, salivary gland, and HPV-related oropharyngeal cancers. He is especially interested in understanding mechanisms of sensitivity or resistance; cancer screening; and using medication and other agents to delay or prevent cancer (chemoprevention). His recent National Institutes of Health (NIH)-funded work in the study of epidermal growth factor receptor inhibitors in head and neck cancer has contributed to the understanding of the biology of this critical signaling network, integration of these agents into standard of care, and definition of mechanisms to overcome resistance. He recently served as chair of the National Cancer Institute (NCI) Head and Neck Cancer Steering Committee, which oversees NCI-funded clinical research in this disease.