1. University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
2. State University of New York Upstate Medical University, Syracuse, New York, USA.
3. Department of Radiation Oncology, University of Florida, Gainesville, Florida, USA.
4. Department of Radiation Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, New York, USA.
5. Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina, USA.
6. Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
7. Department of Radiation Oncology, Mayo Clinic, Jacksonville, Florida, USA.