Affiliation: | 1. 21st Century Oncology, Inc., and The American Board of Radiology, Bethesda, Maryland;2. Department of Radiation Oncology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California;3. Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin;4. Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York;5. The American Board of Radiology, Tucson, Arizona |