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Related to Carcinoid tumour: carcinoid syndrome, Carcinoid tumors


1. a yellow circumscribed tumor of the gastrointestinal tract or bronchus formed from chromaffin cells. See also carcinoid syndrome.
carcinoid syndrome a symptom complex associated with carcinoid tumors (argentaffinomas), marked by attacks of severe cyanotic flushing of the skin lasting from minutes to days and by watery diarrhea, bronchoconstrictive attacks, sudden drops in blood pressure, edema, and ascites. Symptoms are caused by serotonin, prostaglandins, and other biologically active substances secreted by the tumor.

The specific symptoms associated with this disorder depend upon the site of the primary tumor; tumors are found most commonly in the appendix and the terminal third of the ileum but can also be in the bronchi, ovaries, testes, and anywhere along the entire length of the alimentary tract. The full set of carcinoid symptoms are manifested only when the liver is involved.

Diagnosis of the condition is established by a 24-hour urine test for 5-hydroxyindoleacetic acid (5-HIAA), the end product of the breakdown of tryptophan to serotonin. Patients with carcinoid syndrome may have very high levels of 5-HIAA, 100 to 500 mg in 24 hours.

Carcinoid tumors are not always benign and should be approached as if they were malignant growths. Surgical excision of the tumor and any associated mesenteric nodes is the treatment of choice. Chemotherapy can be used with metastatic disease, and other drugs are prescribed as indicated to manage the hypotension, diarrhea, flushing, and other symptoms. Efforts are made to improve nutrition and to avoid serotonin-containing foods, such as walnuts and bananas, which are known to precipitate an attack and make accurate diagnosis difficult.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

car·ci·noid tu·mor

a usually small, slow-growing neoplasm composed of islands of rounded, oxyphilic, or spindle-shaped cells of medium size, with moderately small vesicular nuclei, and covered by intact mucosa with a yellow cut surface; neoplastic cells are frequently palisaded at the periphery of the small groups, and the latter have a tendency to infiltrate surrounding tissue. Such neoplasms occur anywhere in the gastrointestinal tract (and in the lungs and other sites), with approximately 90% in the appendix and the remainder chiefly in the ileum, but also in the stomach, other parts of the small intestine, the colon, and the rectum; those of the appendix and small tumors seldom metastasize, but reported incidences of metastases from other primary sites and from tumors exceeding 2.0 cm in diameter vary from 25-75%; lymph nodes in the abdomen and the liver may be conspicuously involved, but metastases above the diaphragm are rare. About 1% of cases are associated with the carcinoid syndrome, usually after the portal circulation is bypassed as in cases involving liver metastases.
See also: carcinoid syndrome.
Farlex Partner Medical Dictionary © Farlex 2012


A small, slow-growing, benign or malignant tumor, found usually in the gastrointestinal tract, that is composed of islands of rounded cells and secretes serotonin.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


A well-differentiated tumour of neuroendocrine-neural crest origin, which has paracrine activity. 85% of carcinoid tumours are located in the GI tract (appendix, liver, ileum, stomach, colon, rectum),10% in the lungs and bronchi, and the rest in the breast, kidney, ovary, prostate, skin, thymus, and elsewhere.

Clinical findings
Flushing, tachycardia, facial and periorobital swelling, low blood pressure, abdominal pain, weight loss, diarrhoea.
Appendiceal carcinoids are clinically benign; liver carcinoids are usually functionally malignant, as they release large amounts of vasoactive amines (e.g., serotonin) into the circulation.

Increased serotonin, 5-HIAA in serum, urine.

Carcinoids basic classification
Microcarcinoid Tumourlet < 0.5 cm in diameter.
Carcinoid Benign Usually measure > 0.5 cm; either invades muscularis mucosae or is macroscopically visible, but confined to mucosa or submucosa and not angioinvasive.
Borderline carcinoid Either angioinvasive, but measures < 1 cm and is confined to mucosa/submucosa or 1–2 cm, no angioinvasion and limited to the mucosa/submucosa.
Mucinous/goblet cell carcinoid Aggressive; possibly same as agyrophilic adenocarcinoma.
Atypical carcinoid Carcinoid + necrosis OR mitoses > 2/10hpf OR cytological atypia.
Malignant carcinoid Carcinoid + functional tumour OR > 1 cm + angioinvasion OR invades muscularis propria.

Note: The term neuroendocrine tumour is increasingly preferred.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

Patient discussion about carcinoid

Q. what is carcinoid tumors? I had my appendix removed and the doctor came in the room very shocked and said it was full of carcinoid tumors. Im scared to get them somewhere else.

A. ya I have pain all the time but the doctors wont give me anything cuz im so young they don't want me hooked on anything. thank you sooo much for being so kind.

More discussions about carcinoid
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References in periodicals archive ?
Kvols et al., "Guidelines for the diagnosis and management of carcinoid tumours. Part 1: The gastrointestinal tract.
Carcinoid tumours represent a spectrum of slow-growing malignancies that arise from neuroendocrine cells characterised by their ability to produce and secrete peptides.
But their distress was eased by the care and support given to him by Marie Curie Hospice staff in Solihull for four Carcinoid tumours.
Carcinoid tumours arise from neuroendocrine cells but because neuroendocrine cells are not identified within the kidney or renal pelvis, the precise pathogenesis of these lesions remains unclear.
However, relatively benign tumours, in particular slowly growing carcinoid tumours (2,3) can give rise to a clinical syndrome which is indistinguishable from pituitary Cushing disease.
Measurements of chromogranin A, chromogranin B (secretogranin I), chromogranin C (secretogranin II) and pancreastin in plasma and urine from patients with Carcinoid tumours and endocrine pancreatic tumours.
The final histopathological examination confirmed a carcinoid tumour. Immunohistochemical labeling studies demonstrated tumour positivity for chromograffin.
Imaging features of carcinoid tumours of the gastrointestinal tract.
[14] The incidental finding of carcinoid tumour in the appendix also makes this case interesting and necessitates the need for surgical intervention at this point.
At the end of February, my husband and I were told I had a malignant carcinoid tumour, larger than the 3.5cm measured by colonoscopy, and eight out of 10 lymph nodes were infected, plus serosal deposits.
A carcinoid tumour of the testis can be divided into 3 groups: primary carcinoid tumour, metastasis from a different location, and carcinoid tumour arising in a testicular teratoma.[sup.1] Cope was the first to report a testicular carcinoid tumour, a mestastasis from an ileal carcinoid tumour[sup.2] and Simon and colleagues reported the first primary testicular carcinoid tumour in 1954.[sup.3] Although more than 60 cases have been reported to date, testicular carcinoid tumour still remains a very rare disease; moreover, a primary testicular carcinoid tumour with mature teratoma metastatic to the retroperitoneal lymph nodes is extremely rare.[sup.4] Because there was no effective treatment for the metastatic lesions, the prognosis for these cases have been disappointing.[sup.1]