Dr. Lum received her medical degree from Washington University School of Medicine in St. Louis, MO. She completed her residency in General Surgery at Oregon Health and Sciences University in Portland, OR.

Dr. Lum is a Professor Surgery and is the Chair for the Department of Surgery at Loma Linda University School of Medicine. She holds leadership roles in the Southern California Chapter of the American College of Surgeons and the Pacific Coast Surgical Association, and is a Governor in the American College of Surgeons. She is a member of the Health Equity Advisory Group and Legislative Committee of the American Society of Breast Surgeons.