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)

Multiple endocrine neoplasia type 2 (MEN2) is a syndrome characterized by medullary thyroid carcinoma (MTC), unilateral or bilateral pheochromocytoma and hyperparathyroidism. Familial MTC (FMTC) is a subvariant of MEN2 in which affected individuals develop MTC without other manifestations of MEN2. The identification of RET proto-oncogene mutations in MEN2 and FMTC have provided a precise method for identifying gene carriers. This review provides a concise discussion of the use of genetic testing in the management of hereditary MTC, discussing the appropriate use of this new technology with an emphasis on early intervention to prevent death or serious morbidity from this disease.
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PMID:Genetic testing in endocrinology: lessons learned from experience with multiple endocrine neoplasia type 2 (MEN2). 1513

Multiple endocrine neoplasia types 2A and 2B(MEN 2A and MEN 2B), and familial medullary thyroid carcinoma(FMTC) are autosomal, dominantly inherited syndromes involving endocrine tumors. MEN 2A is characterized by medullary thyroid carcinoma(MTC), pheochromocytoma(pheo), and parathyroid hyperplasia; MEN 2B is characterized by MTC, pheo, mucosal ganglioneuroma, and marfanoid habitus. Affected individuals in FMTC families develop MTC without any other abnormalities. MEN 2A and MEN 2B and FMTC are caused by germline mutations in the RET proto-oncogene. To investigate the spectrum of RET mutations among Japanese patients, we analyzed the RET gene 118 patients with MEN 2 or FMTC.
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PMID:[The RET gene in multiple endocrine neoplasia type 2 (MEN 2)]. 1514 13

Multiple endocrine neoplasia 2A (MEN 2A) is an inherited dominant syndrome characterised by medullary thyroid carcinoma, adrenal pheochromocytoma and hyperparathyroidism due to specific RET proto-oncogene mutations. Fertile MEN 2A women are at risk of complicated pregnancy because of unrecognised pheochromocytoma and transmission of RET mutation to the progeny. This condition may cause psychological distress in affected pregnant patients and their families. Here we describe the genetic prenatal testing, the pregnancy management and obstetric outcome in a MEN 2A patient with a right side adrenal hyperplasia and elevated calcitonin levels, a condition suspicious for possible recurrence of pheochromocytoma. We confirm that maternal or fetal complications are rare when MEN 2A diagnosis is made before pregnancy and an accurate monitoring is instituted. Furthermore, our results indicate that prenatal testing for RET mutations is highly recommended in making decisions and assuring parents on the lifelong risk of tumors. This will avoid the psychological distress that can further complicate the pregnancy of affected women.
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PMID:Genetic prenatal RET testing and pregnancy management of multiple endocrine neoplasia Type II A (MEN2A): a case report. 1523 56

Multiple endocrine neoplasia type 2 (MEN-2) is a hereditary syndrome that is transmitted in an autosomal dominant pattern. MEN-2A, MEN-2B, and familial medullary thyroid cancer (MTC) comprise the MEN-2 syndrome. A germline mutation in the RET proto-oncogene is responsible for the MEN-2 syndrome. Recent data indicate that in 99% of MEN-2 cases, a germline RET mutation can be identified by genetic testing. The phenotypic variation of MEN-2 is diverse and partly related to the codon and specific point mutation in the RET proto-oncogene. There are increasing data on the genotype-phenotype correlations in patients with MEN-2 and this information should be used for screening at-risk patients and treatment of RET mutation carriers. All patients (especially if young) with MTC or bilateral pheochromocytoma should have a careful family history taken and genetic screening for RET germline mutations. Patients who are RET germline mutation carriers but without clinical or biochemical evidence of MTC should have a prophylactic total thyroidectomy. The optimal age of thyroidectomy should be based on the RET genotype (eg, high-risk mutations within the first year of life, intermediate-risk mutations by 5 years of age, and low-risk mutations by 10 years of age). Patients who are diagnosed with clinical or biochemical evidence of MTC should have a total or a near total thyroidectomy and at least a central neck lymph node dissection. Patients who have pheochromocytoma and a unilateral adrenal tumor on a localizing study should have a unilateral laparoscopic adrenalectomy after preoperative alpha-blockade. However, patients with bilateral adrenal tumors on localizing studies should have bilateral laparoscopic adrenalectomy. A cortical-sparing (subtotal) adrenalectomy may be considered, if technically feasible, to avoid long-term steroid dependence and to reduce the risk of Addisonian crisis. Patients with biochemical evidence of primary hyperparathyroidism should have a bilateral neck exploration and total parathyroidectomy and autotransplantation (30-60 mg of the most normal parathyroid tissue) to the nondominant forearm if asymmetric parathyroid hyperplasia is present. Rarely, patients may have only single-gland disease and excision may be performed if the other parathyroid glands are not found with biopsy to be hyperplastic. All unresected parathyroid glands should be marked with a clip because patients with MEN-2A have a high risk of persistent and recurrent primary hyperparathyroidism. Patients with familial MTC may have not manifested the other features of MEN-2A, thus these patients should have continued follow-up for pheochromocytoma and primary hyperparathyroidism.
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PMID:Multiple endocrine neoplasia type 2. 1523 8

Medullary thyroid carcinoma (MTC) arises from parafollicular or C cells that produce calcitonin (CT), and accounts for 5-10% of all thyroid cancers. MTC is hereditary in about 25% of cases. The discovery of a MTC in a patient has several implications: disease extent should be evaluated, phaeochromocytoma and hyperparathyroidism should be screened for and whether the MTC is sporadic or hereditary should be determined by a direct analysis of the RET proto-oncogene. In this review, pathological characteristics, tumour markers and genetic abnormalities in MTC are discussed. The diagnostic and therapeutic modalities applied to patients with clinical MTC and those identified with preclinical disease through familial screening are also described. Progresses concerning genetics, initial treatment, follow-up, screening and treatment of pheochromocytoma have permitted an improvement in the long-term outcome. However, there is no effective treatment for distant metastases, and new therapeutic modalities are urgently needed.
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PMID:Medullary thyroid carcinoma. 1535 45

We present the case of a 23-year-old male with a history since early childhood of lip and tongue mucosal neuromas. At the age of 19, he was diagnosed with both medullary thyroid carcinoma and pheochromocytoma within 1 year. These findings, with his marfanoid habitus, led to the diagnosis of multiple endocrine neoplasia type 2 (MEN 2B) syndrome. This was confirmed by a positive RET proto-oncogene. On this admission, he presented with an intestinal obstruction. Abdominal exploration revealed an obstructing tumor mass requiring colectomy, which proved by biopsy to be an intestinal neuroma. This report presents a unique case of a colonic mucosal neuroma causing obstruction in MEN 2B syndrome after the diagnosis of medullary thyroid carcinoma.
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PMID:Multiple endocrine neoplasia type 2 syndrome presenting with bowel obstruction caused by intestinal neuroma: case report. 1558 12

We report the case of a 24-year-old female with a history of medullary thyroid carcinoma who presented at 38 weeks gestation with acute chest pain and shortness of breath. She was found to be in pulmonary edema and respiratory failure. An emergency cesarean section was performed. Subsequently, an echocardiogram revealed an ejection fraction of 10%. After medical therapy with digoxin, milrinone, captopril and diuretics, her condition improved rapidly and a repeat echocardiogram showed that the left ventricular function had normalized. Diagnosis of pheochromocytoma was made by urine and plasma catecholamine measurements. Magnetic resonance imaging revealed a 3.7 cm left adrenal mass. Increased uptake activity was seen in the same region by an (131)I-metaiodobenzylguanidine (MIBG) scan. The patient underwent successful surgical resection of the pheochromocytoma. Subsequent DNA analysis revealed that the patient had a mutation of the RET proto-oncogene. The same mutation was also found in several of her family members. In summary, we report a case of multiple endocrine neoplasia 2A presenting as peripartum cardiomyopathy and cardiovascular collapse. Pheochromocytoma should be considered as a potential cause of peripartum cardiomyopathy.
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PMID:Multiple endocrine neoplasia 2A syndrome presenting as peripartum cardiomyopathy due to catecholamine excess. 1558 45

The heredity of medullary thyroid carcinoma within MEN2 syndrome is caused by heterozygous germline mutations in the RET proto-oncogene. Since MEN2-associated mutations involve only hot spots, the molecular genetic analysis of the RET proto-oncogene constitutes the perfect tool for the diagnosis of MEN2, being thus considered the standard method. The molecular genetic screening for MEN2-associated RET germline mutations should be carried out in all patients with an apparently sporadic medullary thyroid carcinoma or pheochromocytoma. This testing needs to include exons 10, 11, and 13 to 16 of the RET proto-oncogene. Such investigations are aimed at identifying an index person of a new MEN2 family. The detection of such a RET germline mutation is the basis for predictive molecular genetic testing within an affected family, and allows the exclusion or identification of gene carriers. For these family members at risk, prophylactic total thyroidectomy is recommended as a curative procedure, according to a risk-adapted, genetically based treatment algorithm. The management of such affected families should be always complemented by oncological and genetic counselling.
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PMID:Management of patients with hereditary medullary thyroid carcinoma. 1563 Jun 38

Multiple endocrine neoplasia syndrome type II-A (MEN-IIA) is a rare endocrinological disorder occurring in 0.04% of the general population. The combination of papillary thyroid carcinoma with MEN-IIA appears even less frequently. We describe the case of a 21-year-old woman with pheochromocytoma of the left adrenal gland, medullary thyroid carcinoma, hyperplasia of the parathyroid glands and papillary thyroid carcinoma. MEN II-A syndrome resulted from de novo mutation of the RET proto-oncogene, which was detected in the DNA of peripheral blood leucocytes. Three months postoperatively calcitonin levels were normal, whilst increased serum thyroglobulin values prompted the need for further investigation. Whole body scanning with (131)I and with (99m)Tc-sestamibi and also US test of cervical lymph nodes, were negative. The synthetic analogue of somatostatin (99m)Tc-depreotide was used for whole body scintigraphy, cervical and thoracic tomographic scanning and revealed anterior cervical, upper mediastinal and right hilar foci of pathological uptake[Fig.1 and Table 1: see text]. These findings were compatible with findings from CT and MRI that followed in order to complete the diagnostic evaluation. The patient underwent surgical resection of the metastatic foci with uneventful postoperative course. Histology showed lymph node metastases originating from the papillary thyroid carcinoma. Ratio values >2 were abnormal (Fig. 2). Computer processing of the corresponding ROIs on healthy tissues produced the following normal values: Th/Arm: 1.874,, Med/Arm: 1.699, Hi/Arm: 1.141 (Fig. 3).
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PMID:[A patient with MEN-IIA syndrome due to de novo mutation and papillary thyroid carcinoma; the role of 99m Tc-depreotide in diagnosing metastases and brief review of the literature]. 1584 Dec 92

Multiple RET proto-oncogene transcripts, due to genomic variations and alternate splicing, have been described. To investigate endocrine tumor tissue characteristic RET proto-oncogene expression, we performed quantitative RT-PCR, Northern blot and Southern blot analyses of benign and malignant endocrine-derived tissues. We newly describe RET proto-oncogene expression in carcinoid-, gastrinoma- and insulinoma-derived tissue samples. In addition, the presence of a 3'-terminally truncated RET proto-oncogene mRNA variant in benign and malignant thyroid neoplasias, as well as in a pheochromocytoma, an ovarian carcinoma and a medullary thyroid carcinoma, is demonstrated. Southern blot analysis revealed no evidence of gross RET proto-oncogene rearrangements or deletions. As the underlying cause for a bi-allelic TaqI restriction fragment length polymorphism (RFLP), a C (allele 1)/T (allele 2) transition within intron 19, was characterized. This polymorphism is close to a recently described polyadenylation site and lies within a binding site for the nucleic acid binding protein Pbx-1. Screening of healthy subjects and of patients suffering from various endocrine malignancies revealed exclusively allele 1 homozygous and allele 1/allele 2 heterozygous genotypes. Heterozygous genotypes were found in a significantly higher percentage in samples derived from endocrine tumor patients when compared with those from healthy control subjects. Homozygosity for allele 2 was found exclusively in somatic DNA derived from endocrine tumors with high malignant potential. Analysis of DNA derived from varying regions within individual anaplastic thyroid carcinomas revealed an allele 1/allele 2 switch of the RFLP banding pattern, indicating loss of heterozygosity at the RET proto-oncogene locus. In conclusion, our data demonstrate presence of a 5'-terminal RET proto-oncogene transcript in endocrine tissues and reveal a bi-allelic RET proto-oncogene polymorphism. A heterozygous genotype for this polymorphism is found in a considerable number of endocrine tumor patients.
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PMID:A newly identified RET proto-oncogene polymorphism is found in a high number of endocrine tumor patients. 1584 88


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