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)

The presence of a number of regulatory peptides (bombesin, gastrin, glucagon, somatostatin, calcitonin and ACTH) was compared in 30 typical carcinoid tumours and 27 well differentiated neuroendocrine carcinomas (atypical carcinoids) using conventional immunocytochemistry. Strong immunostaining for one or more peptide was observed in 97% of the typical carcinoids (29/30) whereas only 67% of the neuroendocrine carcinomas showed immunoreactivity. The peptide most frequently detected in typical carcinoids was bombesin (67%), while gastrin was more common in neuroendocrine carcinomas (44%). Immunoreactivity for more than one peptide was present in 33 tumours and in three cases, six different peptides were detected. The study shows that immunoreactivity to various peptides is more common in typical carcinoids than well differentiated neuroendocrine carcinomas. The significance of these findings is discussed.
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PMID:Immunoreactivity of various peptides in typical and atypical bronchopulmonary carcinoid tumours. 290 52

An ACTH-producing thymic carcinoid tumour was diagnosed in a 10-year-old girl, 8 years after bilateral adrenalectomy for Cushing's syndrome. The peptides produced by the tumour were characterised thoroughly. High circulating levels of beta-endorphin and other peptides may have contributed to mood and behaviour disturbances.
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PMID:Ectopic ACTH production by a thymic carcinoid tumour. 296 74

Twenty-five patients were identified with non-pituitary, nonadrenal ACTH-secreting tumors (bronchial carcinoid, bronchial small cell carcinoma, pancreatic islet cell carcinoma, medullary thyroid carcinoma, thymic carcinoids, metastatic adenocarcinoma, and pancreatic cystadenoma). Clinical features were weakness, hypertension, cushingoid appearance, peripheral edema, personality disorders, and hyperpigmentation. Biochemical features were a markedly increased urinary free cortisol level (all patients), hypokalemia (71 percent of patients), and an elevated ACTH level (72 percent of patients). Surgical therapy consisted of bilateral total adrenalectomy (56 percent of patients). Twelve percent underwent transsphenoidal hypophysectomy and 36 percent had excision of their tumor. No surgical therapy was undertaken in 28 percent. Bilateral total adrenalectomy in patients with a slow-growing malignancy or an unknown tumor secreting ACTH is beneficial in relieving symptoms and prolonging life. Excision of nonmalignant ACTH-producing tumors yields an excellent long-term prognosis.
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PMID:Ectopic ACTH syndrome. Diagnostic and therapeutic aspects. 298 90

Seventeen patients with well-proven Cushing's syndrome (13 with Cushing's disease, 3 with adrenal tumour and 1 presenting ectopic ACTH syndrome caused by bronchial carcinoid) were investigated by using a single-dose 8 mg dexamethasone nocturnal test. The results obtained were compared with those of the classical 8 mg Liddle's test, metyrapone stimulation, plasma ACTH concentration and with the final diagnosis reached through surgery, pathologic anatomy, and/or clinical and biochemical follow-up of the patients after treatment. The diagnostic efficacy or the predictive power of the test (defined as the ratio between the number of cases in which the diagnosis was correctly predicted and the total number of cases), was at least 82.4% vs 84.6% for the classical 8 mg Liddle's test. This percentage increased to 94.1% when the results of repeated tests on three patients with conflicting data were included. It is concluded that the nocturnal high-dose dexamethasone suppression test is a valuable tool in the aetiological diagnosis of Cushing's syndrome.
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PMID:Nocturnal high-dose dexamethasone suppression test in the aetiological diagnosis of Cushing's syndrome. 299 Jan 31

In order to assess the mechanisms of proopiomelanocortin (POMC) gene expression in human ACTH-producing tumors, we performed the simultaneous evaluation of POMC products and messenger RNA (mRNA) in tissue fragments obtained from two corticotropic adenomas, five nonpituitary tumors, and two normal human pituitaries. The POMC products were examined using a combination of gel exclusion chromatography and four different radioimmunoassays directed against gamma 3 melanocyte stimulating hormone (gamma 3MSH), ACTH, gamma-lipotropin (gamma LPH), and beta-endorphin. The POMCmRNA was detected and analyzed by dot and northern blot hybridization using a single-stranded genomic DNA probe corresponding to the coding region of the human POMC gene. Tissue concentrations of POMC products and mRNA showed parallel distributions. Immunoreactive gamma 3MSH and gamma LPH patterns revealed only 16-kD fragment- and gamma LPH-like peptides in normal and tumoral pituitaries; additional gamma 3MSH- and/or beta MSH-like peptides were found in all five nonpituitary tumors. A single POMCmRNA of approximately 1,200 bases (b) was detected in normal and tumoral pituitaries; a single identical POMCmRNA was also found in four nonpituitary tumors. A thymic carcinoid tumor, in addition to the 1,200-b POMCmRNA, contained equal amounts of a second larger POMCmRNA of approximately 1,450 b. It is concluded that POMC gene expression appears qualitatively unaltered in corticotropic adenomas. In nonpituitary tumors, in contrast, abnormal POMC processing is frequent; in addition, an extra POMCmRNA was detected in a thymic tumor with a greater length than the normal mRNA; the mechanisms and pathophysiological implications of these modifications remain to be elucidated.
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PMID:Altered proopiomelanocortin gene expression in adrenocorticotropin-producing nonpituitary tumors. Comparative studies with corticotropic adenomas and normal pituitaries. 299 96

Three patients presented with hyperpigmentation and high plasma levels of ACTH 4-5 years after bilateral adrenalectomy for Cushing's "disease". X-rays and ct-scan of the lungs showed a small pulmonary mass in all. ACTH levels (1100-2000 pg/ml) were not suppressible by high doses hydrocortisone. A carcinoid tumor was removed in two cases and a chemodectoma in the third. Evidence for ACTH secretion by these tumors was provided by both decrease of ACTH levels after surgery and/or in vitro studies. Both carcinoid cultures showed a basal ACTH production, which was clearly increased by LVP (10(-7) M) and CRF (10(-7) M). Our findings in vitro studies suggest the presence of specific receptor sites for physiological stimuli (LVP and CRF) in tumor cell membranes.
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PMID:Evidence for ectopic ACTH production years after bilateral adrenalectomy for Cushing's syndrome: in vivo and in vitro studies. 300 Nov 67

ACTH response in vivo and in vitro to synthetic ovine corticotropin-releasing factor (o-CRF) was examined in a bronchial carcinoid from a patient with ectopic ACTH syndrome. o-CRF, 1 microgram/kg iv bolus, scarcely increased plasma ACTH or cortisol on one occasion, but they showed a low response on retesting. On the other hand, 10(-8) and 10(-7) M of o-CRF significantly stimulated ACTH release in cultured bronchial carcinoid cells.
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PMID:In vivo and in vitro ACTH response to ovine corticotropin-releasing factor in a bronchial carcinoid from a patient with ectopic ACTH syndrome. 300 73

Three cases of ACTH dependent Cushing's syndrome are reported with emphasis on diagnostic value of selective venous sampling. Case 1. A 44-year-old female was admitted to our hospital with clinical diagnosis of Cushing's disease. Endocrinological examination revealed typical data of Cushing's disease. High resolution CT scan showed an empty sella turcica, and a chest film showed multi-cystic lesion in the left lower lung field. In the first trial of selective venous sampling, central to peripheral ACTH ratio (C/P ratio) was high at the superior vena cava. So, an ectopic ACTH producing lung tumor was strongly suspected. Further examinations for lung tumor were performed, and finally showed lung cryptococcosis. Therefore, selective venous sampling was performed again, and pituitary ACTH dependency was diagnosed. An eccentric pituitary microadenoma was successfully removed by transsphenoidal surgery. Case 2. A 54-year-old female was admitted to our hospital with clinical diagnosis of Cushing's disease. In the endocrinological examinations plasma ACTH was not respond to provocation of LVP or CRF. In selective venous sampling, C/P ratios of ACTH were not greater than 2.0 at any sampling site. Further examinations showed lung tumor in the lower lobe of left lung. This tumor was surgically proved to be an ectopic ACTH producing lung carcinoid. Case 3. A 24-year-old female was admitted to our hospital for the purpose of further examination of Cushing's disease. Three years previously exploratory transsphenoidal surgery demonstrated an empty sella without adenoma. She received postoperative radiation therapy with a dose of 5000 rad. Endocrinological examination showed typical data due to Cushing's disease.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[ACTH dependent Cushing's syndrome with an empty sella turcica: report of three cases with emphasis on diagnostic value of selective venous sampling]. 300 18

Cushing's syndrome is the consequence of a sustained overproduction of cortisol (hydrocortisone) by the adrenal cortex. This may be due to excessive secretion of cortisol by functioning adrenocortical tumors or to "nontumorous" adrenocortical hyperfunction. The latter may be a result of stimulation of the adrenal cortex by increased release of corticotropin (ACTH) from a small pituitary tumor or from nonpituitary nonadrenal tumor. Carcinoids or carcinomas of the lung or pancreas, and even pheochromocytomas have caused the syndrome of ectopic ACTH production. The problems involved in the diagnosis of Cushing's syndrome are establishing its presence and determining the underlying cause. Treatment is then dependent upon the underlying pathogenetic lesion.
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PMID:Diagnosis and pathophysiology of Cushing's syndrome. 300 1

A young female patient, with clinical and biochemical manifestations of severe hypercorticism and with the presence of a pituitary adenoma shown by computerized tomography, was thought to have Cushing's syndrome of hypophysial origin. However, the surgically-removed pituitary adenoma contained no ACTH, by immunocytology, and hypercorticism persisted after transsphenoidal adenomectomy. The patient died and autopsy demonstrated an ACTH and corticotrophin releasing factor (CRF)-containing bronchial carcinoid. It can be concluded that bronchial carcinoids can produce ACTH and CRF and can mimic the clinical and biochemical manifestations of pituitary Cushing's syndrome. Thus, the localization of the primary site of hypercorticism can be extremely difficult in patients who have an insidious, occult extrapituitary tumour. Further work is required to establish whether CRF plays a role in the causation of Cushing's syndrome and whether the simultaneous secretion of this peptide can modify the clinical and biochemical manifestations of the ectopic ACTH syndrome.
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PMID:ACTH and CRF-producing bronchial carcinoid associated with Cushing's syndrome. 302 67


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