A somatostatinoma is a functionally active and usually malignant endocrine tumour with evidence of D-cell differentiation and clinical symptoms reflecting the diverse pathophysiologic effects of chronic inappropriate secretion of somatostatin (hypersomatostatinemia; somatostatinoma syndrome)
Ronald A. DeLellis, Ricardo V. Lloyd, Philipp U. Heitz, Charis Eng
. Somatostatinomas account for between 1 to 2% of endocrine tumours of the gastroenteropancreaticohepatic (GEPH) axis and generally arise in adults.
World Health Organization Classification of Tumours. Pathology and Genetics of Tumors of Endocrine Organs
IARC Press: Lyon 2004
Some somatostatinomas are associated with NF1, MEN1 and Von Hippel-Lindau syndromes; the etiology of their sporadic counterparts is unclear.
Because somatostatinomas are generally large by the time they are detected, nearly two-thirds have already metastasized to the regional lymph nodes or the liver
Axelrod L, Bush MA, Hirsch HJ, Loo SW (1981)
Malignant somatostatinoma: clinical features and metabolic studies.
J Clin Endocrinol Metab 52: 886-96
Shirouzu K, Miyamoto Y, Shiramizu T, Morimatsu M (1985)
Somatostatinoma of the pancreas.
Acta Pathol Jpn 35: 1285-92
Commentary: Neuroendocrine tumours of the digestive system