title: Duodenal neuroendocrine tumor and the onset of severe diabetes mellitus in a US veteran.
abstract: OBJECTIVE
  Neuroendocrine tumors are neoplasms derived from endocrine cells, most commonly occurring in the gastrointestinal tract. Duodenal neuroendocrine tumors are rare tumors averaging 1.2-1.5 cm, and most are asymptomatic. Common presentation is abdominal pain, upper gastrointestinal bleed, constipation, anemia, and jaundice.
  
  
  METHODS
  An adult, Black, male patient with newly diagnosed diabetes mellitus presented to the emergency department with elevated liver function test and fatigue.
  
  
  RESULTS
  Magnetic resonance cholangiopancreatography demonstrated a large obstructing mass (3.6 cm × 4.4 cm × 3 cm) within the second and third portions of the duodenum at the ampulla. Esophagogastroduodenoscopy demonstrated an ulcerated duodenal mass that was biopsied. Immunohistochemical stains were positive for synaptophysin, chromogranin B, and CK7. Chromogranin A was in normal range. Post-Whipple procedure demonstrated a 5.5 cm × 4.1 cm × 2.9 cm duodenal mass with invasion of the subserosal tissue of the small intestine, a mitotic rate of 2 per high-power field, and antigen Ki-67 of 2%-5%.
  
  
  CONCLUSIONS
  This case raises the question as to if the patient developed diabetes mellitus due to the tumor size and location or if the new onset of diabetes was coincidental. This case also demonstrates the importance of a proficient history and physical.
authors.affiliation: Lake Erie College of Osteopathic Medicine, Bradenton, FL, USA.
authors.forename: Lauren
authors.initials: L
authors.lastname: Murray
authors.affiliation: Department of Clinical Investigation, Womack Army Medical Center, Fort Bragg, NC, USA.
authors.forename: Chelsey
authors.initials: C
authors.lastname: Haley
authors.affiliation: Department of Clinical Investigation, Womack Army Medical Center, Fort Bragg, NC, USA.
authors.forename: Cristóbal S
authors.initials: CS
authors.lastname: Berry-Cabán
authors.affiliation: Lake Erie College of Osteopathic Medicine, Bradenton, FL, USA.
authors.forename: Almond
authors.initials: A
authors.lastname: Toledo
keywords: Duodenal; military; neuroendocrine tumor