Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Endocrine tumors (ET) of the digestive tract (formerly called neuroendocrine tumors) are rare. They are classified into two principal types: gastrointestinal ET's (formerly called carcinoid tumors) which are the most common, and pancreaticoduodenal ET's. Functioning ET's secrete polypeptide hormones which cause characteristic hormonal syndromes. The management of ET is multidisciplinary. Poorly-differentiated ET's have a poor prognosis and are treated by chemotherapy. Surgical excision is the only curative treatment of well-differentiated ET's. The surgical goals are to: 1. prolong survival by resecting the primary tumor and any nodal or hepatic metastases, 2. control the symptoms related to hormonal secretion, 3. prevent or treat local complications. The most common sites of gastrointestinal ET's ( carcinoids) are the appendix and the rectum; these are often small (<1 cm), benign, and discovered fortuitously at the time of appendectomy or colonoscopic removal. Ileal ET's, even if small, are malignant, frequently multiple, and complicated in 30-50% of cases by bowel obstruction, mesenteric invasion, or bleeding. The carcinoid syndrome (consisting of abdominal pain, flushing, diarrhea, hypertension, bronchospasm, and right sided cardiac vegetations) is caused by the hypersecretion of serotonin into the systemic circulation; it occurs in 10% of cases and is usually associated with hepatic metastases. More than half of the cases of pancreatic ET are non-functional. They are usually malignant and of advanced stage at diagnosis presenting as a palpable or obstructing mass or as liver metastases. Insulinoma and gastrinoma (cause of the Zollinger-Ellison syndrome) are the most common functional ET's. 80% are sporadic; in these cases, tumor size, location, and malignant potential determine the type of resection which may vary from a simple enucleation to a formal pancreatectomy. In 10-20% of cases, pancreaticoduodenal ET presents in the setting of multiple endocrine neoplasia (NEM type I), an autosomal-dominant genetic disease with multifocal endocrine involvement of the pituitary, parathyroid, pancreas, and adrenal glands. For insulinoma with NEM-I, enucleation of lesions in the pancreatic head plus a caudal pancreatectomy is the most appropriate procedure. For gastrinoma with NEM-I, the benefit of surgical resection for tumors less than 2-3 cm in size is not clear. The lesions are frequently small, multiple, and widespread and recurrence is frequent after excision. The long-term prognosis is nevertheless fairly good. But the eventual development of liver metastases which are the most common cause of mortality still argues for an aggressive surgical approach in the early stages of the disease.
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PMID:[Surgical treatment of gastric, enteric, and pancreatic endocrine tumors Part 1. Treatment of primary endocrine tumors]. 1614 76

MEN 1 syndrome (Multiple Endocrine Neoplasia type 1) is a rare endocrine disorder characterized by the association of tumors in several endocrine glands, mainly in parathyroids, gut and pituitary. At our institution in the years 1982-2004 we have followed 26 patients with MEN 1 syndrome belonging to 19 families. The diagnosis of MEN 1 was based on Gubbio Consensus (JCEM 86: 5658-5671, 2001). Mean age at the diagnosis of MEN 1 was 35 years. Primary hyperparathyroidism was the most frequent pathology, which was diagnosed in 25 of 26 patients (96%). Gut endocrine tumors were found in 20 patients (77%), while pituitary tumors in 18 (70%). Non-functioning gut tumors were most frequent (n=9), followed by insulinoma (n=7) and gastrinoma (n=4). Prolactinoma was the most frequent pituitary tumor found in 12 patients (67%). Three patients died during the observation period - all of them of generalized gut endocrine tumor (gastrinoma in 2 cases and foregut carcinoid in one case). The management of MEN 1 is not easy and careful analysis of clinical picture is necessary in each individual case. Several important observations can be made on the basis of own experience and the literature: 1. In each sporadic pathology, which may be a part of MEN 1, one should consider. the possibility of MEN 1. The individual MEN 1 abnormalities are often diagnosed after 40 and later 2. MEN 1 tumor are usually multiple thus necessitating a different therapeutic approach (more radical surgery) 3. The most valuable screening tests are: Ca++, PP, CgA and prolactin 4. Endoscopic ultrasound is the most specific method for the localization of pancreatic endocrine tumors. 5. The results of surgical treatment of MEN 1 tumors are worse than that of sporadic tumors. 6. Prognosis in MEN 1 is determined by the behaviour of gut neuroendocrine tumor 7. No genotype/phenotype correlation in MEN 1 syndrome was found so far. In summary, it should be underlined that MEN 1 syndrome is an endocrine disorder, in which early diagnosis and optimal treatment may significantly improve the prognosis.
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PMID:[Diagnostic and therapeutic difficulties in MEN 1 syndrome]. 1635 Jul 23

Tumors and metastases bearing the somatostatin receptor subtypes 2 (SSTR2) or SSTR5 can be visualized in vivo after injection of radiolabeled octapeptide somatostatin analogs like 111In-pentetreotide. The sensitivity of 111In-pentetreotide scintigraphy for the detection of carcinoid tumors is 86-95%. The sensitivity of 111In-pentetreotide scintigraphy for the detection of gastrinomas, vasoactive intestinal polypeptide-secreting tumors, and glucagonomas as well as clinically non-functioning lesions is 75-100%. However, for insulinoma this is 50-60%. 111In-pentetreotide scintigraphy generally has a lower detection rate for benign pheochromocytomas than 123I-MIBG scintigraphy, but it can have a complementary role for the staging of malignant pheochromocytomas. It can also be used for the detection of extra-adrenal pheochromocytomas and paragangliomas. Most GH- and TSH-secreting pituitary adenomas can be visualized using 111In-pentetreotide. 111In-pentetreotide scintigraphy is negative in microprolactinomas and ACTH-secreting pituitary microadenomas. 111In-pentetreotide scintigraphy has been successful for the localization of extra-pituitary ACTH-secreting tumors and their metastases, and especially for occult tumors. A large variety of lesions in and around the pituitary region express somatostatin receptors and, therefore, can be visualized by 111In-pentetreotide scintigraphy.
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PMID:Neuroendocrine tumors and somatostatin: imaging techniques. 1662 62

Gastrin receptor scintigraphy (GRS) is a new imaging method primarily developed for the detection of metastases of medullary thyroid carcinoma (MTC). As gastrin-binding CCK(2) receptors are also expressed on a variety of other neuroendocrine tumours (NET), we compared GRS to somatostatin receptor scintigraphy (SRS) in patients with NET. SRS and GRS were performed within 21 days in a series of 60 consecutive patients with NET. GRS was directly compared with SRS. If lesions were visible on GRS but not detectable by SRS, other imaging modalities (MRI, CT) and follow-up were used for verification. Of the 60 evaluable patients, 51 had carcinoid tumours, 3 gastrinomas, 2 glucagonomas, 1 insulinoma and 3 paragangliomas. The overall tumour-detection rate was 73.7% for GRS and 82.1% for SRS. In the 11 patients with negative SRS, GRS was positive in 6 (54.5%). Based on the number of tumour sites detected and the degree of uptake, GRS performed better than SRS in 13 patients (21.7%), equivalent images were obtained in 18 cases (30.0%) and SRS performed better in 24 (40.0%) cases. In six of the SRS positive patients, 18 additional sites of tumour involvement could be detected. Overall, GRS detected additional tumour sites in 20% of the patients. Localisation of the primary tumours or their functional status had no influence on the outcome of imaging. GRS should be performed in selected patients as it may provide additional information in patients with NET with equivocal or absent somatostatin uptake.
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PMID:Added value of gastrin receptor scintigraphy in comparison to somatostatin receptor scintigraphy in patients with carcinoids and other neuroendocrine tumours. 1715 65

We report a rare case of symptomatic hypoglycemia in a patient with intra-abdominal recurrence of a previously resected gastrointestinal stromal tumor (GIST). The patient is a 65-year-old woman who underwent resection of a large abdominal mass arising from the stomach, histologically diagnosed as a high-grade leiomyosarcoma. She was lost to follow up. Five years later, the mass recurred; core biopsy demonstrated a CD 117-positive, spindle-cell tumor, consistent with a GIST. She was placed on Gleevec, as there was evidence of multifocal disease, but imaging revealed only mild improvement. Subsequently, her clinical status deteriorated, and she was hospitalized for dehydration, vomiting, and mental status changes. Her blood glucose on admission was 22 mg/dL, and a dextrose infusion (50%) was necessary to maintain adequate blood glucose levels. Measurements of insulin, proinsulin, c-peptide, beta-hydroxybutyrate, and thyroid-stimulating hormone were normal, as were cosyntropin stimulation and glucagon response tests. Suspicions arose for tumor-secreted insulin-like factor. She underwent resection of the dominant 44-cm recurrence, with immediate rebound hyperglycemia, followed by complete normalization of her blood glucose levels. She was discharged on postoperative Day 5 without symptoms or insulin, and is alive with disease at 20 months. Paraneoplastic syndromes occur in only 15 per cent of patients with known malignancies (e.g., lung cancer and metastatic carcinoid), and are rarely reported in the setting of GIST. Hypoglycemia is most often observed in presence of insulinoma and only isolated case reports in GIST patients exist. Overexpression of insulin-like growth factor II is thought to be the mechanism of action. Supportive management and palliative resection or debulking is recommended when possible.
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PMID:Hypoglycemia in the setting of advanced gastrointestinal stromal tumor. 1721 25

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

Neuroendocrine tumours of the gastrointestinal tract and pancreas present a major challenge to physicians in their recognition and treatment requirements, and surgical treatment of these tumours has become increasingly important for symptom palliation and survival. For some carcinoid tumours the extent of surgery may depend on tumour size. Midgut carcinoid is the most common cause of the carcinoid syndrome, requiring surgery for primary and mesenteric tumours to minimize the risk for abdominal complications but also for removal of liver metastases to palliate hormonal symptoms. Among endocrine pancreatic tumours, insulinoma and gastrinoma often cause severe symptoms of hormone excess despite their inconspicuous size, but they can be successfully removed with improved pre- and intraoperative localization. Other tumours--glucagonoma, VIPoma, and non-functioning endocrine pancreatic tumours--are often large or metastasizing, but generally require surgical debulking to alleviate hormonal symptoms and have favourable survival.
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PMID:Surgery on neuroendocrine tumours. 1738 67

Gastro-entero-pancreatic tumors (GEP) contain, in their majority, somatostatin receptors. In-111-DTPA-phenyl-pentetreotide has been proved to have high affinity for somatostatin receptors subtypes 2, 3 and 5. The aim of the present study was to evaluate the utility of (111)In-DTPA-O somatostatin receptors' scintigraphy (SRS) in the diagnosis of suspected GEP. Thirty-five consecutive patients (17 males and 18 females-mean age 57.9+/-7.6) with GEP as a possible diagnosis were enrolled in the study. The primary diagnosis was diarrheic syndrome susceptive of intestinal carcinoid tumor (24 patients), carcinoid of the rectum (2 patients), adenocarcinoma of the pancreas (2 patients), insulinoma (2 patients), gastrinoma (3 patients) and hepatocellular carcinoma (2 patients). All patients were submitted to computerized tomography (CT) of the thorax and the abdomen and pentetreotide SRS was performed 4 h (total body and SPET acquisition) and 24 h (planar views), post iv injection of 185 MBq of the radiolabeled compound. Results showed: Four of the patients were false positive diagnosed as having inflammatory intestinal disease and gallbladder dilatation. At the time of the evaluation, 14 of the remaining patients were free of disease, concerning secondary involvement. In these cases, CT and SRS studies matched each other, with no pathological lesions and no abnormal accumulation of the radiopharmaceutical respectively. Concerning pathological cases, only one SRS study in a patient with rectum carcinoid was normal, with liver lesions in the CT study. These lesions were considered as subtypes 2, 3 and 5 somatostatin receptors negative. SRS revealed three lesions more than CT. According to these results, sensitivity of SRS study was 93.8% and specificity 86.9%. The authors believe that molecular imaging of somatostatin receptors, is a sensitive method for the evaluation of patients with GEP tumors. However, in cases of intestinal disease, we should be aware of false positive results due to inflammatory processes and the presence of lymphocyte infiltration.
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PMID:[Indium-111-DTPA-phenyl-pentetreotide somatostatin receptors' scintigraphy in the evaluation of patients with suspected gastro-entero-pancreatic tumors. Comparison with computerized tomography]. 1808 69

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by tumors of the parathyroid glands, the anterior pituitary, and the endocrine pancreas. Our patient was a 58-year-old man who manifested typical features of MEN-1 including primary hyperparathyroidism, lung carcinoid, and lipomas and insulinoma. He was admitted to our hospital because of recurrent hypoglycemia and a growth of pancreatic tumors. The first operation for insulinoma was performed when he was 20 years old. We found a germline mutation of the MEN1 gene (E45G, exon 2) in this patient. According to these examinations and his clinical course, the patient was diagnosed as having a recurrence of insulinoma. He subsequently underwent surgery for the pancreatic tumors. The majority of these tumor cells were immunohistochemically positive for insulin and negative for glucagon. A few nodules showed immunohistochemical staining positivity for glucagon but they were negative for insulin. Although it is uncommon for patients with MEN1 to exhibit insulinoma and glucagonoma, this case suggests the need for careful analysis of pancreatic tumors in patients with MEN1.
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PMID:Co-existence of glucagonoma with recurrent insulinoma in a patient with multiple endocrine neoplasia-type 1 (MEN-1). 1935 Apr 20

Sporadic multiple endocrine neoplasia type 1 (MEN1) is defined as the occurrence of tumours in two of three main endocrine tissue types: parathyroid, pituitary and pancreaticoduodenal. A prolactinoma variant or Burin variant of MEN1 was found to occur in three large kindreds, with more prolactinomas and fewer gastrinomas than typical MEN1. MEN1 tumours differ from common tumours by showing features from the MEN1 gene (e.g. larger pituitary tumours). They also show various expressions of tumour multiplicity; however, pituitary tumour in MEN1 is usually solitary. Diagnosis in MEN1 carriers during childhood is not directed at cancers but at benign morbid tumours. Morbid prolactinoma occurred at the age of 5 years in one MEN1 individual; hence, this is the earliest age at which to recommend tumour surveillance in carriers. The MEN1 gene shows biallelic inactivation in 30% of some types of common variety endocrine tumours (e.g. parathyroid adenoma, gastrinoma, insulinoma and bronchial carcinoid), but in only 1-5% of common pituitary tumours. Heterozygous knockout of MEN1 in mice provides a robust model of MEN1 and has been found to support further research on anti-angiogenesis therapy for pituitary tumours. The rarity of MEN1 mutations in some MEN1-like states aids the identification of other mutated genes, such as AIP, HRPT2 and p27(Kip1). We present recent clinical and basic findings about the MEN1 gene, particularly concerning hereditary vs. common variety pituitary tumours.
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PMID:The MEN1 gene and pituitary tumours. 1940 9


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