Dr. Leslie Busby, originally from Montana, earned his BS in Biology at Montana State University, his MD from the University of Nevada School of Medicine, and completed his Internal Medicine residency at the University of Missouri-Kansas City in 1999. After a fellowship in Hematology and Oncology at the University of Utah, he joined Rocky Mountain Cancer Centers (RMCC) in Boulder, Colorado, in 2002. He has also held multiple leadership roles, both with RMCC as the practice’s first medical director and with The Network’s Pharmacy & Therapeutics (P&T) Committee, where he has served as chair since 2019. In addition to his deep clinical expertise and commitment to high-quality patient care, he completed his MBA from Colorado State University in 2022 and participated in The Network’s Tier 3 leadership training, a program designed to refine executive skills in finance, strategy, and organizational management. In July 2025, he became Chief Medical Officer of USON.