1. abcdeFrom the Department of Radiation Oncology, Huntsman Cancer Hospital, Salt Lake City, Utah; Department of Radiation Oncology, Roswell Park Cancer Institute, Buffalo, New York; Department of Radiation Oncology, M. D. Anderson Cancer Center, University of Texas, Houston, Texas; Department of Radiation Oncology, University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan; and Department of Radiation Oncology, Duke Comprehensive Cancer Center, Durham, North Carolina.