M.D.
Surgeon, Surgical Oncologist
Aaron G. Lewis, M.D., is a board-certified surgical oncologist with wide-ranging experience in cancer surgery. At City of Hope® South Pasadena, Dr. Lewis focuses on conducting complex procedures involving the digestive system and endocrine glands, often using advanced tools like the da Vinci® robotic surgical system to perform minimally invasive operations.
Dr. Lewis’ research interests include improving outcomes and daily life for patients with advanced neuroendocrine tumors and enhancing surgical care for older adults and medically frail individuals, a group he believes deserves more attention in research and clinical trials.
Dr. Lewis joined the City of Hope team following a fellowship here, during which he earned the Values in Action Award for compassionate care. He received his medical degree from the Medical College of Wisconsin in Milwaukee, completed his internship at the University of California, San Francisco, and his residency at Huntington Memorial Hospital in Pasadena, California, where he also participated in the Phil Simon Clinic Tanzania Project, a global health initiative.