Dr. David Marshall is a board-certified radiation oncologist, specializing in genitourinary and gastrointestinal cancers. He has been recognized by Castle Connolly as a Top Doctor in radiation oncology from 2016 to present. Dr. Marshall has published widely in GI and GU cancers and has brought innovative treatment options to the people of South Carolina, including Y-90 microsphere therapy and radiosurgical treatment for liver cancers, and new techniques using linked/stranded seeds for prostate cancer patients. In addition, Dr. Marshall is interested in the development of novel ways of improving accuracy of radiotherapy using new immobilization and image-guided techniques. Dr. Marshall is the chair of the Department of Radiation Oncology. He has been at MUSC for more than 15 years. He is also the associate director of the radiation oncology resident training program at MUSC, and enjoys working with residents to both improve the care of his patients and educate future radiation oncologists. He also functions as the medical director for the Clinical Trials Office at the Hollings Cancer Center, an NCI-designated cancer center. He is active in several national scientific and professional organizations, including: the American Society for Radiation Oncology, the American College of Radiation Oncology, the American Brachytherapy Society, the Southwestern Oncology Group (SWOG); and NRG Oncology.