Pancreatic somatostatinoma characterized by extreme hypoglycemia

Somatostatinomas are very rare endocrine tumors, accounting for less than 1% of all gastrointestinal endocrine tumors. It usually arises within the pancreas and some from extrapancreafic sites, including the duodenum, ampulla, jejunum, or cystic duct,with an annual incidence of 1 in 40 million. Since the first case of pancreatic somatostafinoma was reported in 1977 by Larsson et al,4 less than 200 cases of somatostatinoma have been reported in literature, and only a few cases have been reported in China. The most described features of patients with somatostatinoma induced by excessive somatostatin secretion are characterized by cholelithiasis, steatorrbea, achlorhydria, hypochlorhydria and mild hyperglycemia, As somatostafin inhibits the secretion of insulin from pancreatic islets,