argentaffinoma


argentaffinoma

 [ahr″jen-taf″ĭ-no´mah] a carcinoid tumor of the gastrointestinal tract formed from argentaffin cells, usually in the terminal ileum or appendix; such tumors elaborate a variety of catecholamines that produce the symptom complex called carcinoid syndrome. Called also carcinoid.

argentaffinoma

(1) Carcinoid tumour. 
(2) An obsolete, nonspecific term for any tumour with staining affinity for silver salts—e.g., carcinoids, APUDomas and pancreatic islet cell tumours; most argentaffinomas are neuroendocrine cell tumours.

argentaffinoma

Oncology A tumor located anywhere in the GI tract–± 90% in appendix, remainder are in the ileum, stomach, colon or rectum or lungs, which secretes excess serotonin, evoking a carcinoid syndrome. See APUD system, Carcinoid syndrome.

car·ci·noid tu·mor

(kahr'si-noyd tū'mŏr) A neoplasm composed of cells of medium size, with moderately small vesicular nuclei; neoplastic cells are frequently palisaded at the periphery of small groups. Such neoplasms occur in the gastrointestinal tract, the lungs, and other sites, with approximately 90% in the appendix.
See also: carcinoid syndrome
Synonym(s): argentaffinoma.