1 Walter National Military Medical Center (WRNMMC), Department of Surgery, Bethesda, MD, United States; National Cancer Institute, Division of Cancer Prevention (DCP), Gastrointestinal & Other Cancers Research Group, Rockville, MD, United States. Electronic address: rodrigul@mail.nih.gov.
2 National Cancer Institute, Division of Cancer Prevention (DCP), Biometry Research Group, Rockville, MD, United States. Electronic address: izmirlig@mail.nih.gov.
3 Digestive Diseases Division, Uniformed Services University, Bethesda, MD, United States. Electronic address: Patrick.e.young1.civ@mail.mil.