Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031511 (pheochromocytoma)
 14,622 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary multiple endocrine neoplasia, type 2 (MEN 2) comprises medullary thyroid carcinoma (MTC) and bilateral pheochromocytoma; the syndrome includes two major variants, MEN 2a (normal appearance, parathyroid disease common) and MEN 2b (mucosal neuromas, Marfanoid habitus, parathyroid disease rate). Patients with MEN 2a may be normocalcemic, with normal basal serum immunoreactive parathyroid hormone (iPTH) levels, yet have parathyroid hyperplasia discovered during thyroid surgery. In an attempt to predict the presence of this occult parathyroid hyperplasia, we performed calcium infusion (15 mg Ca++/kg/4 hours) in six patients with MEN 2a, seven patients with MEN 2b, and eight normal subjects. iPTH was measured in samples taken at one hour intervals during the infusion with a sensitive radioimmunoassay (antiserum GP 1M [Arnaud]). The iPTH values (expressed as per cent of the basal value) in the normal, MEN 2a, and MEN 2b groups at the fourth hour were 38.0 +/- 3.8% (mean +/- SE), 79.2 +/- 7.2%, and 47.8 +/- 5.2%. These iPTH values for patients with MEN 2a were significantly different from normal (P less than 0.001) and from those of the patients with MEN 2b (P less than 0.001). All MEN 2a patients had parathyroid hyperplasia at cervical exploration; parathyroid histology in the MEN 2b patients was normal. Failure of iPTH suppressibility in the MEN 2a patients was not due either to the plasma calcitonin or to achieved serum calcium concentrations. The normal iPTH suppressibility in MEN 2b is consistent with the concept that the parathyroid disease in MEN 2a is genetically determined, and not secondary to MTC and high plasma calcitonin concentration. Calcium infusion combined with the measurement of serum iPTH levels may detect occult parathyroid hyperplasia in patients with MEN 2a, normocalcemia, and normal basal iPTH values. The identification and follow-up of similar patients should establish the natural history of this unusual parathyroid disease.
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PMID:Preoperative diagnosis of occult parathyroid hyperplasia by calcium infusion in patients with multiple endocrine neoplasia, type 2a. 95 Mar 71

Experience with 17 children in one kindred with familial medullary carcinoma of the thyroid and pheochromocytoma has demonstrated the utility and validity of periodic provocative testing by calcium infusion or pentagastrin injection in the identification of children with early medullary carcinoma of the thyroid or its premalignant precursor, C-cell hyperplasia. In these 17 patients with two consecutive elevations of calcitonin levels greater than 0.55 ng/ml after stimulation all but one have had MTC or CCH at operation. Total thyroidectomy has been well tolerated and can be performed with an acceptably low incidence of complications in this group of patients.
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PMID:Total thyroidectomy for occult familial medullary carcinoma of the thyroid in children. 99 55

Serum calcium, serum immunoreactive parathyroid hormone (PTH), and plasma immunoreactive calcitonin were measured in 12 patients with catecholamine-secreting tumors. Only two patients had high serum calcium and immunoreactive PTH concentrations (one also had high basal immunoreactive calcitonin); in both, the hypercalcemia persisted after removal of their pheochromocytomas but was corrected by removal of hyperplastic parathyroid glands and medullary thyroid carcinomas. Of the 10 patients with normal serum calcium and immunoreactive PTH concentrations, 2 had high immunoreactive calcitonin concentrations and medullary thyroid carcinomas alone were found. Our results suggest that [1] hypercalcemia occurs infrequently in patients with pheochromocytoma, [2] chronic circulating catecholamine excess does not cause increased immunoreactive PTH or immunoreactive calcitonin secretion in patients with pheochromocytoma, and [3] the parathyroid disease in patients with pheochromocytoma is a genetically determined component of multiple endocrine neoplasia.
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PMID:Parathyroid function in patients with pheochromocytoma. 111 71

1. Three members of a kindred and a fourth unrelated individual demonstrating the syndrome of mucosal neuroma, bumpy lips, marfanoid habitus, medullary thyroid carcinoma and pheochromocytoma are reported, and the literature pertaining to this syndrome has been reviewed. 2. There are currently 41 definite and 16 additional probable reported cases manifesting the syndrome of mucosal neuroma, bumpy lips, pheochromocytoma and medullary thyroid carcinoma. Mucosal neuroma was present in all patients. Medullary thyroid carcinoma was histologically proved in 38 cases. Pheochromocytoma was documented in 19 patients with a probable diagnois in another 4 patients. Only one patient was noted to have hypercalcemia associated with parathyroid adenoma. Associated abnormalities seen in this syndrome include hypertrophied corneal nerves, skeletal defects and gastrointestinal tract abnormalities. 3. The relationship of this syndrome to other types of multiple endocrine neoplasia syndromes and the phakomatoses is also discussed. This syndrome appears to be distinct from the entity of multiple endocrine neoplasia type 2. We suggest that this syndrome be called multiple endocrine neoplasia type 3, following the classification originally proposed by Steiner et al. 4. MEN type 3 appears to be inherited as an autosomal dominant disorder. Many apparently non-familial cases have been reported, but due to inadequate information regarding family history it may be possible that some of these cases also had other affected family members. 5. This syndrome most likely results from a dysplasia of neuroectodermal tissue. The pathogenesis of this syndrome is discussed and evidence supporting the hypothesis is reviewed. 6. The importance of diagnosing the syndrome at an early stage and of investigating the relatives of a patient manifesting this potentially fatal syndrome are stressed. 7. Plasma calcitonin measurement following calcium infusion is extremely useful as a screening procedure for the diagnosis of medullary thyroid carcinoma, when the patients are completely asymptomatic and routine thyroid function tests are normal. Affected individuals should also be periodically screened for the development of pheochromocytoma.
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PMID:Mucosal neuroma, pheochromocytoma and medullary thyroid carcinoma: multiple endocrine neoplasia type 3. 111 36

1. In the fifth year of followup, 8 of 12 original patients thyroidectomized for MTC, diagnosed solely by abnormal calcitonin values, are disease free by all criteria. Elevated calcitonin levels are the only manifestation of active disease in three patients with presumed metastases. 2. Routine annual screening of susceptible individuals is a practical measure and has in 6 cases detected the premalignant condition of G-cell hyperplasia and in 1 patient a premetastatic state of MTC. It is premature to conclude that yearly screening is sufficient to detect all cases of premetastatic disease and for this reason we are recommending a yearly screen with pentagastrin and calcium tests and the more convenient pentagastrin test at 6 month intervals for those in the high-risk age group between 8 and 18. If screening at such intervals proves to be ineffective in preventing the disease in every case, consideration must be given to prophylactic thyroidectomy although we are not currently recommending this precedure. 3. Pentagastrin injection is often a more effective secretagogue for calcitonin than is calcium infusion, but this is not uniformly true. We therefore recommend use of both tests as the most appropriate screening procedure. 4. Epinephrine is a major secretory product of pheochromocytomas in the J-kindred and sequential E/N ratios may be of use in the early detection of pheochromocytoma in other kindreds. 5. Adrenal medullary hyperplasia has been found in 3 adrenal glands and is probably a preneoplastic condition analogous to C-cell hyperplasia.
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PMID:Natural history of the familial medullary thyroid carcinoma-pheochromocytoma syndrome and the identification of preneoplastic stages by screening studies: a five-year report. 122 35

An increase in the cellular concentration of cAMP leads to the inhibition of platelet aggregation. We have been investigating endogenous peptides which inhibit platelet function, using an assay which detects increase in platelet cAMP. Compared with the human adrenal medulla, a pheochromocytoma (PC) contained abundant peptides that elevate platelet cAMP. About 90% of the activity was found in the SP-III fraction which contained strongly basic peptides. From the SP-III fraction, peptides P-1, P-2 and P-3 were purified to homogeneity as endogenous peptides which elevated platelet cAMP. A gas phase sequencer was used to identify these peptides as follows: P-1 = vasoactive intestinal peptide (VIP); P-2 = calcitonin gene related peptide-I (CGRP-I); P-3 = CGRP-II. It is well known these peptides are potent vasorelaxants. VIP and CGRP-I significantly increased platelet cAMP levels 15- and 6-fold, respectively. These results suggest that VIP and CGRP-I and -II act upon platelets as well as upon vascular tissue.
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PMID:Isolation and characterization of peptides which act on rat platelets, from a pheochromocytoma. 131 39

A variety of vasoactive substances including biogenic amines, neuropeptide Y, somatostatin, enkephalin, ACTH, corticotropin-releasing hormone, growth hormone releasing hormone, vasoactive intestinal peptide, calcitonin, and atrial natriuretic factor have been extracted from intra-adrenal and extra-adrenal pheochromocytomas in men. Some of them appear to play an important role for the development of hypertension or clinical serious symptoms. However, informations on the molecular forms of other substances in pheochromocytomas are still limited, and precise amount of the peptides or hormones in the tumors has not yet been quantitated. Numerous in vitro or in vivo studies of this documented neoplasm over the years have been reviewed in this manuscript. Clinical analyses of early diagnosis, localization diagnosis, treatment of multiple endocrine neoplasia, preoperative and operative treatments are also evaluated in this paper. These informations will probably provide additional evidence for the multi-secretory APUD cells of neural crest origin and will contribute the therapy in patients with pheochromocytoma.
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PMID:[Pheochromocytoma--basic and clinical analyses]. 134 92

Despite its rarity, medullary thyroid carcinoma which is hereditary in a quarter of cases and often associated with multiple endocrine neoplasia 2a and 2b syndromes, avises much interest which has lead to the formation of a French multidisciplinary group for the study of calcitonin tumors. This collaboration has resulted in the establishment of a national register and has broadened the knowledge of all specialists concerned. Consequently diagnostic methods are improved, becoming quicker, more reliable and also more thorough due to the setting up of therapeutic protocols. An immunocytochemical staining for calcitonin allows a preoperative diagnosis, providing optimal therapeutic conditions for the patients, especially systematic research of pheochromocytoma and management by a specialized team. Total thyroidectomy and careful lymph node dissection are recommended for all cases. Such progress significantly modifies the prognosis of the disease. Family screening, using plasma calcitonin and, in the near future, genetic studies will hopefully enable the identification of abnormal gene carriers before the clinical stage, thus making total recovery possible.
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PMID:[Medullary cancer of the thyroid and multiple endocrine neoplastic syndromes]. 135 14

We describe familial cases of multiple endocrine neoplasia (MEN) 2B: A 48-year-old man is the proband. He had pheochromocytoma, medullary thyroid carcinomas (MTCs), parathyroid hyperplasia, mucosal neuromas, eversion of eyelids and Marfanoid appearance, and then underwent adrenalectomy and total thyroidectomy. Family screening revealed that his two daughters (10 and 8 years old) had mucosal neuromas and increased serum calcitonin (CT). Both of them had MTCs but no pheochromocytoma, and their MTCs were surgically removed. The father and his children have been in favorable condition since the operations. Southern blot analysis with 33 polymorphic DNA probes was done in MTCs obtained from two daughters. An RBP3 (10q11.2) locus linked to a predisposing gene on chromosome 10 was uninformative in either patient because of constitutional homozygosity. Loss of heterozygosity at the MYCL1 locus on chromosome 1p32 was observed in MTC from the younger sister, but no loss of heterozygosity was recognized in other loci examined. Deletion of the 1p32 locus may play a role in the development of MEN 2B.
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PMID:A kindred of multiple endocrine neoplasia type 2B. 135 66

This paper presents our experience in four families having the multiple endocrine neoplasia (MEN) II-A syndrome, with a total of 19 affected patients. All had medullary thyroid carcinoma (MTC), 6 also had pheochromocytoma (PH) and 3 had hyperparathyroidism. The screening of the members of the families to measure basal and pentagastrin response calcitonin (CT) serum levels allowed an early diagnosis of medullary thyroid carcinoma, when lesions were only 1 mm in diameter. Measurement of vanillymandelic acid, catecholamines and metanephrines in 24-hour urine collections allowed the diagnosis of pheochromocytoma in patients, some of whom were asymptomatic. A clear relationship was found between the age of the patients, the basal serum calcitonin level and size of the MTC.
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PMID:[Multiple endocrine neoplasia II A syndrome: relationship between age of the patient, levels of basal calcitonin and size of the thyroid tumor]. 135 95


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