Expert Directory

William K. Oh, MD

Chief Medical Science Officer, Sema4
Clinical Professor of Medicine
Division of Hematology and Medical Oncology
Icahn School of Medicine at Mount Sinai
New York, NY

William K. Oh, MD, is chief medical science officer at Sema4, a patient-centered health intelligence company focused on precision medicine. He is also clinical professor of medicine in the Division of Hematology and Medical Oncology at the Tisch Cancer Institute at the Icahn School of Medicine at Mount Sinai. 

Dr Oh received his MD from New York University School of Medicine. He completed his internship and residency in internal medicine at Brigham and Women’s Hospital in Boston and completed his medical oncology fellowship at the Dana-Farber Cancer Institute. He was at the Dana-Farber Cancer Institute and Harvard Medical School for 14 years, where he served as clinical director of the Lank Center for Genitourinary Oncology and was founding chair of the Data and Safety Monitoring Committee at the Dana-Farber/Harvard Cancer Center. Most recently, Dr Oh was chief of the Division of Hematology and Medical Oncology at the Icahn School of Medicine at Mount Sinai for 11 years. He also served as deputy director of the Tisch Cancer Institute at the Icahn School of Medicine at Mount Sinai, which he helped to achieve National Cancer Institute designation in 2015 and renewed in 2020.

Dr Oh is an expert in the management of genitourinary (GU) malignancies, including prostate, renal, bladder, and testicular cancers. A leading investigator in the use of systemic treatments for prostate cancer, Dr Oh has served as the principal investigator for multiple clinical trials in GU cancers. In addition, he has developed large clinical databases and specimen repositories for GU cancers at both Harvard and Mount Sinai. He has authored more than 300 original articles, reviews, and book chapters on topics related to prostate, renal, bladder, and testicular cancers. He has also edited 3 books on prostate cancer. 

Dr Oh has served in key invited roles for the American Society of Clinical Oncology, the American Cancer Society, and the American Urological Association, including the Guidelines Committee for Castration-Resistant Prostate Cancer. He was inducted into the prestigious American Society for Clinical Investigation and has been repeatedly selected as a Top Doctor in New York Magazine, Castle Connolly, Best Doctors, and Super Doctors through 2021.