1. Department of Radiation Oncology, University of North Carolina, Chapel Hill
2. Department of Radiation Oncology, University of Florida Hospitals, Gainesville3Shands Cancer Center, University of Florida Hospitals, Gainesville
3. Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill5Division of Hematology/Oncology, Department of Medicine, University of North Carolina, Chapel Hill
4. Gillings School of Global Public Health, University of North Carolina, Chapel Hill
5. Division of Cancer Control and Population Sciences, National Cancer Institute, Rockville, Maryland
6. Department of Radiation Oncology, University of North Carolina, Chapel Hill4Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill