Somatostatinoma (SSoma) is an extremely rare pancreatic neuroendocrine tumor or duodenal endocrine tumor (see these terms) that originates either in the pancreas (50%) or the gastrointestinal tract (50%) and mainly presents with non-specific symptoms of abdominal pain, weight loss, jaundice and diarrhea but, in approximately 20% of pancreatic cases, leads to a somatostatin hypersecretion syndrome (somatostatinoma syndrome) characterized by diabetes mellitus, cholelithiasis, steatorrhea and hypochlorhydria.