1. aDepartment of Radiation Oncology, and
2. bDivision of Biostatistics, Department of Clinical Sciences, University of Texas Southwestern, Dallas, Texas;
3. cMcGraw/Patterson Center for Population Sciences, Dana-Farber Cancer Institute, Boston, Massachusetts; and
4. dDivision of Surgical Oncology, Department of Surgery, and
5. eDivision of Hematology/Medical Oncology, Department of Internal Medicine, University of Texas Southwestern, Dallas, Texas.