1. 1John P. Murtha Cancer Center Research Program, Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
2. 2Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
3. 3Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
4. 4The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, Maryland.