Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Among endocrine tumors occurring in the gastrointestinal tract, midgut argentaffin EC cell carcinoids, gastric argyrophil ECL cell carcinoids, duodenal gastrin cell tumors, and rectal trabecular L cell carcinoids (in order of decreasing frequency) are those occurring more frequently. Together, they account for more than 80% of such tumors. Duodenal somatostatin cell tumors, gangliocytic paragangliomas, and differentiated neuroendocrine carcinomas are also well-defined tumor entities. The carcinoid syndrome, either classical, with intermittent flushing, hypotension, and diarrhea, or atypical, with persistent histamine-type red flushing, bronchospasm, and no diarrhea, and Zollinger-Ellison syndrome, with severe peptide ulcer disease, are the only hyperfunctional syndromes consistently found in association with these tumors. The carcinoid syndrome occurs in about 10% of gastrointestinal carcinoids, usually in their advanced, metastatic stage. The Zollinger-Ellison syndrome occurs in association with about 40% of intestinal gastrin cell tumors, including small intramural growths. Tumor prognosis depends on the mode and site of presentation, histology, cell type(s), size, level of invasion, metastases (especially distant metastases), and associated clinical syndrome or background disease. Hormones, trophic factors, inherited genetic traits, somatic mutations, and some chronic inflammatory processes are pathogenetically important in a large proportion of cases.
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PMID:The pathology of the gastrointestinal endocrine system. 812 73

The purpose of the workshop was to critically evaluate the use of octreotide in the management of important surgical and gastroenterological conditions. The topics covered included: (1) management of functioning gut neuroendocrine tumors, (2) new approaches to localize these tumors, (3) the place of octreotide in the treatment of variceal bleedings, and (4) the use of octreotide in postoperative conditions. Octreotide therapy has been shown to be effective in the carcinoid syndrome, in which symptom control is achieved in 85% of patients, and reduction in 5-HIAA in 60%. Although tumor regression is rarely seen, prolongation of survival probably occurs. Control of diarrhea has been achieved in 84% of patients with VIPoma treated with octreotide. Similarly, octreotide has been found to provide effective control of the necrolytic, migratory dermatitis seen in glucagonoma. By contrast, insulinomas are more resistant to somatostatin agonist therapy. In the Zollinger-Ellison syndrome, octreotide is effective in alleviating symptoms and in reducing serum gastrin levels. However, its use in this syndrome has been superceded by omeprazole. Radioiodine-labelled octreotide has been very effective in in vivo imaging of neuroendocrine tumors in the abdomen, and is now considered the best available technique for localizing these tumors preoperatively. Intraoperative localization with a hand-held gamma camera is being developed. There is an exciting future possibility to use the technique to deliver therapy to tumors. Octreotide therapy has been shown to be at least as effective as and without the adverse hemodynamic effects of Pitressin in control of variceal hemorrhage. It should be regarded as one of several modalities of therapy in the condition.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Somatostatin analogue therapy in functioning neuroendocrine gut tumors. 835 71

Long-acting somatostatin analogs, such as octreotide, comprise the therapeutic modality of choice for the symptomatic relief of flush and diarrhea in patients with carcinoid syndrome. The sequelae of gastric acid hypersecretion in patients with gastrin-producing duodenal carcinoids (gastrinoma) are perfectly controlled by proton pump inhibitors. Antiproliferative medical strategies to control the growth of metastatic carcinoid tumors include long-acting somatostatin analogs, interferon alpha, and the combination of the two. However, the success rate is less than 50%, and it is questionable whether true tumor regression can be expected. Controlled prospective studies are mandatory to address the question whether interferon or somatostatin analogs or the combination of the two should be used as first-line medical strategies and if hepatic artery embolization in patients with liver metastases should be performed before beginning medical therapy. Chemotherapy, including etoposide and cisplatin, has been shown to be effective only for purely differentiated neuroendocrine carcinomas and not for slowly growing carcinoids.
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PMID:Medical treatment of metastasizing carcinoid tumors. 866 18

Gastroenteropancreatic (GEP) neoplasms originate from any of the various cell types belonging to the neuroendocrine system. A general characteristic of GEP endocrine tumours is that the vast majority produce and secrete a multitude of peptide hormones and amines. Many patients with malignant metastasising tumours present clinical symptoms related to hormone hyperproduction. These include the so-called carcinoid syndrome, characterised by flushing, diarrhoea, wheezing and right heart disease, which is predominantly associated with the serotonin- and tachykinins-producing carcinoids of the midgut. Several types of syndrome associated with GEP endocrine tumors are caused by overproduction of a specific hormone. For instance, the well-known Zollinger-Ellison syndrome is gastrin-mediated. The so-called 'insulinoma syndrome' depends on excessive production of insulin and proinsulin, resulting in hypoglycemia. The 'glucagonoma syndrome' is characterised by necrolytic migratory erythema, diabetes and diarrhoea. The Verner-Morrison syndrome, which is brought about by high circulating levels of vasointestinal peptide (VIP). produces severe secretory diarrhoea. Finally the 'somatostatinoma syndrome' involves gallbladder dysfunction and gallstones, diarrhoea with or without steatorrhea, and impaired glucose tolerance. The biochemical diagnosis of endocrine digestive tumors is based on general and specific markers. The best general markers are chromogranin A (CgA) and pancreatic polypeptide (PP). Specific markers for endocrine tumors include insulin, gastrin, glucagon, vaso intestinal polypeptide (VIP), somatostatin and the primary cathabolic product of serotonin, 5-hydroxyndoleacetic acid (5-HIAA). Localisation procedures commonly applied, in the diagnosis of endocrine tumours include ultrasound (US), computed tomography (CT) and somatostatin receptor scintigraphy (SRS).
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PMID:Epidemiology, clinical features and diagnosis of gastroenteropancreatic endocrine tumours. 1176 60

This study was undertaken to supplement our previous analysis of 635 duodenal carcinoids to give both wider and different viewpoints on a larger series of duodenal endocrinocarcinomas, and to provide up-to-date clinicopathologic information regarding these neoplasms. A total of 927 cases of such neoplasms of the duodenum were collected from the Niigata Registry for gut-pancreatic endocrinomas, consisting of the carcinoid group with 897 cases, 857 typical carcinoids and 40 atypical varieties, and the variant group with 30 remaining endocrinocarcinomas expressed by various terminology. Significant statistical differences between these two groups were evident in various aspects: in sites of tumor growth, aggressiveness of invasion to the extra-duodenal structures, rates and sites (liver, lymph nodes and bone) of metastases, average tumor-size, immunohistochemistry of gastrin and serotonin, rates of recurrence, five-year survival rates and others. In addition, a close similarity between these two groups was noted in several aspects of histology, histochemistry and immunohistochemistry, rendering the variant group in a member of the carcinoid family. Regarding the carcinoid group in comparison with that in other organs may be summarized as follows: a reasonable male/female ratio of 1.39, a reasonable average age of 55.9 years, a high typical/atypical ratio of 21.4, a relatively small average tumor-size of 17.7 mm, a relatively low metastasis rate of 27.4%, a high histologic B-type dominance of 75.5%, a high postoperative survival rate of 83.3% and a reasonable incidence of the carcinoid syndrome of 3.1%.
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PMID:Endocrinocarcinomas (carcinoids and their variants) of the duodenum. An evaluation of 927 cases. 1458 91

Type I gastric carcinoid tumors result from hypergastrinemia in 1%-7% of patients with pernicious anemia. We diagnosed pernicious anemia in a 48-year-old female patient with complaint of fatigue for three months. She had no gastrointestinal symptoms. Endoscopic examination ot the upper gastrointestinal tract revealed atrophic gastritis and a polypoid lesion in the corpus of 3-4 mm in size. Endoscopic polypectomy was performed. Histopathological examination of the specimen revealed positive chromogranin A and synaptophysin stainings compatible with the diagnosis of a carcinoid tumor. Serum gastrin level was increased, urinary 5-hydroxyindoleacetic acid was within the normal range. There was no other symptom, sign, or laboratory finding of a carcinoid syndrome in the patient. No metastasis was found with indium-111 octreotide scan, computed tomographies of abdomen and thorax. Type I gastric carcinoid tumors are only rarely solitary and patients with tumors < 1 cm in size may benefit from endoscopic polypectomy.
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PMID:Treatment of solitary gastric carcinoid tumor by endoscopic polypectomy in a patient with pernicious anemia. 1683 Mar 92

We reviewed the clinicopathologic profile of a series of recently diagnosed sporadic duodenal gastrin-cell (G-cell) tumors. All cases were discovered incidentally and had a unique clinicopathologic profile: all 18 cases were gastrin-positive tumors located in the duodenal bulb, were small in size (mean size 5.4 mm), demonstrated an insular architectural pattern, and were localized to the lamina propria and submucosa. None of the patients had Zollinger-Ellison or carcinoid syndrome. The behavior was indolent and there was no evidence of metastasis at diagnosis or during follow-up. In our sampled population, the presence of Helicobacter pylori gastritis and the use of proton pump inhibitors (PPIs) were significantly associated with the presence of G-cell tumors. Both the presence of H. pylori gastritis and use of PPI remained significant in a logistic regression model adjusted for age, race/ethnicity, and sex with P values of 0.0016 (odds ratio=10.1, 95% confidence interval: 2.3 to 42.4) and 0.008 (odds ratio=8.9, 95% confidence interval: 1.76 to 45.4), respectively. Most patients with tumors showed G-cell hyperplasia in the nontumorous regions of the duodenum. The high incidence of sporadic duodenal G-cell tumors in patients with H. pylori gastritis and long-term PPI use suggests an association that needs to be further explored. Presence of G-cell hyperplasia in the nontumorous duodenal mucosa suggests that these may originate from a proliferative phase, similar to the hyperplasia-dysplasia-neoplasia sequence seen in other endocrine tumors.
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PMID:Sporadic duodenal bulb gastrin-cell tumors: association with Helicobacter pylori gastritis and long-term use of proton pump inhibitors. 1712 15

Several circulating or urinary tumour markers can be used for the diagnosis and follow-up of functioning and clinically non-functioning neuroendocrine tumours of the pancreatic islet cells and intestinal tract. Among the specific tumour markers are serotonin and its metabolites--e.g. 5-hydroxyindoleacetic acid (5-HIAA)--in carcinoid tumours and the carcinoid syndrome, insulin and its precursors or breakdown products in insulinoma, and gastrin in gastrinoma. Plasma vasointestinal polypeptide (VIP) determinations have been used in the diagnosis of VIPoma, plasma glucagon for glucagonoma, and serum somatostatin for somatostatinoma. Among the tumour-non-specific markers are: chromogranins, neuron-specific enolase (NSE), alpha-subunits of the glycoprotein hormones, catecholamines, pancreatic polypeptide (PP), ghrelin and adrenomedullin.
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PMID:Biochemistry of neuroendocrine tumours. 1738 64

Serum gastrin levels exceeding 1000pg/ml (normal, <100) usually raise the suspicion for a neuroendocrine tumor (NET) that secretes gastrin. Rarely, such elevated gastrin levels are seen in patients with pernicious anemia which most commonly is associated with autoimmune gastritis (AG). AG can occur concomitantly with other autoimmune disorders including lymphocytic colitis (LC). Gastrin stimulates enterochromaffin-like cells which increase histamine secretion. Histamine excess can cause diarrhea as can bacterial overgrowth or LC. We present a 57-year-old woman with diarrhea, sporadic epigastric pain, and bloating. She also had a history of interstitial cystitis and took pentosan polysulfate and cetirizine. She had no history of ulcers, renal impairment or carcinoid syndrome. Fasting serum gastrin was 1846pg/ml. Esophagoduodenal gastroscopy and biopsies revealed chronic gastritis and a pH of 7 with low stomach acid. Serum gastrin and plasma chromogranin A were suggestive of a gastrinoma or NET. Pernicious anemia was unlikely. Imaging studies did not reveal any tumor. Random colonic biopsy was compatible with LC, possibly explaining her diarrhea, although we also considered excessive histamine from elevated gastrin, bacterial overgrowth, and pentosan polysulfate which can cause diarrhea and be misleading in this setting, pointing to the diagnosis of gastrinoma. At 4year follow-up in 2012, fasting serum gastrin was 1097pg/ml and the patient asymptomatic taking only cetirizine for nasal allergies. This case illustrates that diarrhea may be associated with very high serum gastrin levels in the setting of chronic gastritis, LC, and interstitial cystitis (pentosan use), without clear evidence for a gastrinoma or NET. If no history of ulcers or liver metastases is present in such cases, watchful observation rather than an extensive/invasive and costly search for a NET may be justified. Considering the various forms of polyglandular syndrome, this may represent a variant and we here provide an algorithm for working up such patients, while also reviewing literature on the intertwined relationship between the immune and endocrine systems.
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PMID:The various faces of autoimmune endocrinopathies: non-tumoral hypergastrinemia in a patient with lymphocytic colitis and chronic autoimmune gastritis. 2304 3

Neuroendocrine tumors are usually slow-growing tumors. Many of these are capable of secreting peptide hormones or biogenic amines that may lead to endocrine syndromes. Nonfunctioning tumors can either secrete no hormones at all, or secrete hormones not giving rise to endocrine symptoms, such as chromogranin A, chromogranin B or pancreatic polypeptide. Chromogranin A is produced by the majority of endocrine tumors, both functioning and nonfunctioning, and is the best available marker for diagnosis, follow-up and treatment monitoring of patients with differentiated neuroendocrine tumors. Examples of endocrine syndromes are classical carcinoid syndrome caused by serotonin (measured in the urine as its metabolite 5-HIAA), insulinoma syndrome caused by insulin or proinsulin, Zollinger-Ellison syndrome resulting from gastrin secretion, glucagonoma syndrome caused by glucagon, WDHA syndrome caused by vasoactive intestinal peptide, or Cushing's syndrome resulting from ectopic production of adrenocorticotropic hormone or corticotropin-releasing hormone. In case there is uncertainty about the diagnosis, specific tests can be applied, such as the secretin test for diagnosis of gastrinomas and the 72-hour fast for diagnosis of an insulinoma. In patients with suspicion of an inherited syndrome, such as multiple endocrine neoplasia (MEN) 1 and MEN2 syndromes, genetic testing is indicated.
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PMID:Biochemical Testing in Patients with Neuroendocrine Tumors. 2630 2


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