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)

Catecholamine-secreting metastatic carcinoid should be considered in differential diagnosis of malignant pheochromocytoma. Paroxysmal functioning or hormonally silent gastroenteropancreatic neuroendocrine tumors (GEP NETs) require repeat biochemical measurements and sensitive anatomic and functional imaging studies overlapping those for malignant pheochromocytoma. This report presents clinical, laboratory, and radiologic findings in a patient presenting with heart rate variability; vasoactive headaches reactive to ethanol, tyramine and tryptophan; labile blood pressure; diaphoresis; diarrhea; abdominal pain; unexplained pancreatitis; joint pain; and paroxysmal flushing with pallor. GI studies (including endoscopic ultrasound) and multiple imaging modalities (including 2D CT, MRI with gadolinium, [18]FDG PET/CT, [123I]MIBG, and SRS [111In]Octreotide [OctreoScan]) were not diagnostic. 24-h BP, Holter and 30-day cardiac event monitors plus urinary biochemical studies consistently suggested catecholamine-synthesizing NET. NIH plasma metanephrines studies and [6]-[18F]Fluorodopamine PET ruled out malignant pheochromocytoma (pheo). Repeated studies showed persistently abnormal GEP NET biomarkers and urinary catecholamines. Capsule endoscopy revealed suspicious submucosal lesions throughout the small intestine. Dual-phase 64-slice multidetector computed tomography (MDCT) with 3D volumetric reconstruction of the abdomen and pelvis revealed multiple diffuse liver metastases and three extrahepatic lesions consistent with metastatic carcinoid. In combination, intensive biochemical testing repeated over time, dual-phase 64-slice MDCT with 3D image reconstruction and volume-rendering (VR) technique, and advanced radionuclide imaging are required to detect NETs' sporadic or paroxysmal functioning, rule out extra-adrenal pheochromocytoma, and localize and characterize metastatic carcinoid. If pheochromocytoma is ruled out, yet symptoms and biochemical markers for catecholamine excess are present, then carcinoid and other amine-precursor-uptake decarboxylation (APUD) tumors must remain in the differential diagnosis.
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PMID:Catecholamine-secreting metastatic carcinoid as differential diagnosis in pheochromocytoma: clinical, laboratory, and imaging clues in the search for the lurking neuroendocrine tumor (NET). 1710 73

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

Ectopic acromegaly represents less than 1% of the reported cases of acromegaly. Although clinical improvement is common after treatment with somatostatin (SMS) analogs, the biochemical response and tumor size of the growth hormone-releasing hormone (GHRH)-producing tumor and its metastases are less predictable. Subject A 36-year-old male was referred because of a 3-year history of acromegaly related symptoms. He had undergone lung surgery in 1987 for a "benign" carcinoid tumor. Endocrine evaluation confirmed acromegaly Plasma IGF-1: 984 ng/ml (63-380), GH: 49.8 ng/ml (<5). MRI showed a large mass in the left cerebellopontine angle and diffuse pituitary hyperplasia. Pulmonary, liver and bone metastases were shown by chest and abdominal CT scans. Ectopic GHRH secretion was suspected. Methods Measurement of circulating GHRH levels by fluorescence immunoassay levels and immunohistochemical study of the primary lung tumor and metastatic tissue with anti-GHRH and anti-somatostatin receptor type 2 (sst2A) antibodies. Results Basal plasma GHRH: 4654 pg/ml (<100). Pathological study of liver and bone biopsy material and lung tissue removed 19 years earlier was consistent with an atypical carcinoid producing GHRH and exhibiting sst2A receptor expression. Treatment with octreotide LAR 20-40 mg q. month resulted in normalization of plasma IGF-1 levels. Circulating GHRH levels decreased dramatically. The size of the left prepontine cistern mass, with SMS receptors shown by a radiolabeled pentetreotide scan, decreased by 80% after 18 months of therapy. Total regression of pituitary enlargement was also observed. No changes were observed in lung and liver metastases. After 24 months of therapy the patient is asymptomatic and living a full and active life.
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PMID:Ectopic growth hormone-releasing hormone secretion by a metastatic bronchial carcinoid tumor: a case with a non hypophysial intracranial tumor that shrank during long acting octreotide treatment. 1737 89

Neuroendocrine tumors may arise from a wide range of organs and may occur in various locations in the body. They include carcinoid tumors, paragangliomas (pheochromocytomas), medullary thyroid carcinomas, and islet cell tumors of the pancreas. In this article the authors focus on the more common tumors with origins primarily in the abdomen, namely carcinoid, paraganglioma, and pancreatic islet cell tumors. Imaging assists in delineating the sites and extent of disease, in preoperative planning for resection of the primary tumor and metastatic disease, and in follow-up. Discussion is restricted to the main imaging modalities used in these tumors: cross-sectional imaging, namely CT and MRI, and nuclear medicine studies.
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PMID:Imaging of neuroendocrine tumors. 1754 32

The middle ear is a rare site for benign tumors. We report six patients with benign middle ear tumors surgicaly removed: three with carcinoid, one with adenoma, and two with paraganglioma. These tumors showed similar histological features in trabecular and glandular architecture, so further immunohistochemical study was needed to make a definitive histopathological diagnosis. When we analyzed clinical features of patients diagnosed immunohistochemically, the differentiation of two patients with paraganglioma from the remaining four with adenomatous tumors such as adenoma and carcinoid was relatively easy from otomicroscopic findings and enhancement in temporal bone MRI. It was however difficult to differentiate patients with adenomatous tumors from each other because they induced similar clinical symptoms and showed similar findings in images. For a definitive diagnosis, it is necessary to conduct exploratory tympanotomy or removal of the tumors to obtain enough specimen for histological and immunohistochemical studies. Tumors induced no bone destruction or complications. We recommend staged operations for total removal of tumors and for good postoperative hearing.
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PMID:[Immunohistochemical and clinical features of patients with benign middle ear tumors]. 1756 30

Neuroendocrine adenomas are rare tumors, which can appear in the middle ear. Approximately a hundred cases have been reported in the literature. We report the case of a 58-year-old man who consulted for an abnormal sensation of fullness in the right ear. The otoscopic examination showed a retrotympanic tumefaction. The CT scan and MRI of the middle ear demonstrated a well-defined tissue mass without any osteolysis. We performed surgical exeresis by transcanal procedure with a cartilage graft tympanoplasty. Microscopic examination and immunohistochemistry revealed an endocrine adenoma of the middle ear. Neuroendocrine adenomas can develop in a number of different sites. When they appear in the middle ear they usually produce hypoacousia. The otoscopic examination shows non-specific findings with only retrotympanic swelling. Surgical exeresis enables histologic and immunohistochemically analysis of the surgical specimen. The adenoma is composed of two cellular types: neuroendocrine (which closely resemble carcinoid tumors) and glandular. Regular clinical and radiologic follow-up is necessary since recurrence is possible. The formal diagnosis of neuroendocrine adenomas of the middle ear requires histologic and immunohistochemically confirmations since the clinical symptoms are non-specific. Surgical excision with removal of the ossicular chain is the treatment of choice in order to prevent recurrence.
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PMID:Neuro-endocrine adenoma of the middle ear: a case study. 1763 40

Carcinoid tumors of the extrahepatic bile ducts are extremely rare and account for only 0.2-2% of all gastrointestinal endocrine neoplasms. They are particularly difficult to diagnose preoperatively and distinguish from cholangiocarcinoma. We report the case of a 52-year-old patient with a carcinoid tumour of the common bile duct presenting with obstructive jaundice. Laboratory and imaging studies (US, CT, MRI) showed an obstructive lesion measuring 2 cm in diameter in the common bile duct. A biliary stent was inserted initially to decompress the bile ducts. Brushing was negative for malignant cells. With a suspicion of malignancy (confirmed intraoperatively), the patient underwent radical resection of the extrahepatic duct, portal lymphadenectomy and a Roux-en-Y hepaticojejunostomy. The pathology examination revealed a well-differentiated neuroendocrine tumour of the common hepatic duct. The tumour cells were immunopositive for chromogranin A and synoptophysin. There was no evidence of metastases in the nodes removed and negative surgical margins were achieved. The patient is disease-free after a follow up of 3 months, and levels of chromogranin A and neuron-specific enolase are normal. Local and systemic aggressiveness of these tumours is rare. Radical surgery offers the only chance of a cure and has to be considered whenever possible.
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PMID:[Carcinoid tumours of the bile ducts]. 1766 84

Carcinoid tumors account for less than 1% of all malignancies. The majority arise in the gastrointestinal system (GI carcinoids). The diagnosis of GI carcinoids is often made late, the protean symptoms are easy to overlook. Diagnosis, prognosis and treatment options are based on biochemical markers and imaging investigations. A high concentration of urinary 5-HIAA or an elevated serotonin level in plasma help to establish the diagnosis of GI carcinoid. Plasma chromogranin A has poor specificity (68%); its level depends on disease involvement and therapeutic response. Octreoscan is the best imaging technique to detect GI carcinoids, but CT scan and MRI are superior for the detection of metastasis. 18F-DOPA or 11C-5-HTP/PET, imaging fusion as of octreoscan or PET scan with CT or MRI, improve the results of metabolic imaging. Coronal contrast-enhanced CT or MRI angiogram can evaluate mesenteric vessel spread before surgery. Upper endoscopy or colonoscopy, can be performed to detect foregut carcinoid in MEN, or hindgut carcinoid. Echoendoscopy visualizes abdominal wall and local node involvement. Enteroscopy and capsule endoscopy localize 66% of midgut carcinoids. Although there have been considerable advances in diagnostic modalities, the diagnosis of carcinoid tumors is still, all too often, late.
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PMID:[Gastrointestinal carcinoid tumors: a multi-technique diagnostic approach]. 1792 31

Once the diagnosis of Cushing's syndrome (CS) has been established, the main step is to differentiate between ACTH dependent and independent disease. In adults, 80% of CS is due to ACTH-dependent causes and 20% due to adrenal causes. ACTH-secreting neoplasms cause ACTH-dependent CS. These are usually anterior pituitary microadenomas, which result in the classic Cushing's disease. Non-pituitary ectopic sources of ACTH, such as a small-cell lung carcinoma or carcinoid tumours, are the source of the remainder of ACTH-dependent disease. In the majority of patients presenting with clinical and biochemical evidence of CS, modern non-invasive imaging can accurately and efficiently provide the cause and the nature of the underlying pathology. Imaging is essential for determining the source of ACTH in ectopic ACTH production, locating the pituitary tumours and distinguishing adrenal adenomas, carcinomas and hyperplasias. In our chapter we review the adrenal appearances in ACTH-dependent and ACTH-independent CS. We also include a discussion on the use of MRI and CT for the detection and management of pituitary ACTH secreting adenomas. CT of the chest, abdomen and pelvis with intravenous injection of contrast medium is the most sensitive imaging modality for the identification of the ectopic ACTH source and detecting adrenal pathology. MRI is used for characterising adrenal adenomas, problem solving in difficult cases and for detecting ACTH-secreting pituitary adenomas.
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PMID:Imaging in Cushing's syndrome. 1820 70

Ectopically ACTH producing tumors may be difficult to localize by conventional radiology and functional imaging may be helpful. Case 1: 31-year-old man was diagnosed with ectopic ACTH-dependent Cushing's syndrome (ECS). Thorax CT revealed a 1.3 cm nodular opacity in upper left lobe, suggestive of residual lesion. [(18)F] fluoro-2-deoxy-D: -glucose ([(18)F] FDG) positron emission tomography ([(18)F] FDG PET) scan revealed mild glycolytic metabolic activity. Pathological examination confirmed an ACTH-positive carcinoid tumor. Case 2: 53-year-old woman presented with very rapid onset ECS. Pituitary MRI was normal. Thorax CT revealed no tumoral lesion. Abdominal and pelvic MRI showed images suggestive of hepatic and iliac, femoral and lumbar secondary implants. [(18)F] FDG PET scan revealed intense uptake in uterus, especially cervix, suggesting this to be the primary tumor site. These cases illustrate the role of [(18)F] FDG PET in the investigation of an ECS where conventional imaging studies were not elucidative in the search for a responsible tumor.
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PMID:Utility of [(18)F] fluoro-2-deoxy-D: -glucose positron emission tomography in the localization of ectopic ACTH-secreting tumors. 1845 46


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