1. Department of Pediatrics, Walter Reed National Military Medical Center, Bethesda, MD, USA
2. Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
3. Lombardi Comprehensive Cancer Center, Georgetown University, Washington D.C., USA
4. John P. Murtha Cancer Center, Walter Reed National Military Medical Center, Bethesda, MD, USA
5. Department of Pathology and Laboratory Services, Walter Reed National Military Medical Center, Bethesda, MD, USA