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1/91. Normal thyroid pathology in patients undergoing thyroidectomy for finding a RETgene germline mutation: a report of three cases and review of the literature.

    Genetic screening for germline RET proto-oncogene mutation in hereditary medullary thyroid cancer (MTC) is accurate and allows for preventive total thyroidectomy to be performed early in patients who are gene carriers. We report 3 children who underwent preventive total thyroidectomy based on the finding of a RETgene germline mutation, but who had no evidence of MTC or C-cell hyperplasia on permanent histology, even after calcitonin immunostaining. review of the English literature of patients undergoing preventive thyroidectomy for a positive RETgene germline mutation, shows that 3.4% of these patients (a total of 209 patients) had normal thyroid glands. Also, 8.6% of patients undergoing preventive total thyroidectomy with prophylactic central neck node dissection had cervical node metastases. We conclude that preventive thyroidectomy in patients screened early for germline RETgene mutation allows for earlier diagnosis and treatment of patients, sometimes even before any hyperplasia or neoplasia can be demonstrated because cervical node metastases can occur early and be demonstrated even with small tumors (< 1 cm), we recommend prophylactic central neck node dissection at the time of preventive thyroidectomy. ( info)

2/91. Unilateral laparoscopic adrenalectomy followed by contralateral retroperitoneoscopic partial adrenalectomy in a patient with multiple endocrine neoplasia type 2a syndrome.

    We report the first patient who had bilateral pheochromocytoma associated with multiple endocrine neoplasia type 2a syndrome (men 2a) and underwent unilateral laparoscopic adrenalectomy followed by contralateral retroperitoneoscopic partial adrenalectomy 2 years later. The postoperative course was uneventful both times, and the patient was cured of hypertension without any need for steroid replacement. Endoscopic partial adrenalectomy is a minimally invasive procedure for pheochromocytoma with mild symptoms. We believe that this procedure has considerable potential for treating bilateral pheochromocytoma, which is frequently observed in patients with men 2a. ( info)

3/91. multiple endocrine neoplasia type 2a with the identical somatic mutation in medullary thyroid carcinoma and pheochromocytoma without germline mutation at the corresponding site in the RET proto-oncogene.

    A germline mutation either in exon 10 or 11 of the RET proto-oncogene is found in the majority of patients with multiple endocrine neoplasia type 2a (men 2A). A 41-year-old female patient was referred for further evaluation of incidentally discovered right adrenal tumor. She had bilateral adrenal pheochromocytomas and medullary thyroid carcinomas detected by endocrinological and radiological examination, and diagnosed as men 2A. Molecular genetic testing of the RET exons 10 and 11 exhibited the identical somatic missense mutation at codon 634 in both tumors but did not confirm germline mutations in the corresponding sites. Possible mechanisms for tumorigenesis in this patient are discussed. ( info)

4/91. A novel case of multiple endocrine neoplasia type 2a associated with two de novo mutations of the RET protooncogene.

    We report a novel case of multiple endocrine neoplasia type 2a (men 2A) associated with two mutations of the protooncogene RET. One affects codon 634 and causes a cysteine to arginine substitution; the second at codon 640 causes an alanine to glycine substitution in the transmembrane region. The two mutations were present on the same RET allele and were detected in germline and tumor dna. Both mutations were de novo, i.e. they were not found in the dna of the parents or relatives. Immunohistochemical and RT-PCR analysis showed that the pheochromocytoma expressed calcitonin as well as both RET alleles. A cell line established from the tumor and propagated in culture sustained the expression of RET and calcitonin, as did the original pheochromocytoma. Because the patient presented with medullary thyroid carcinoma and pheochromocytoma without parathyroid gland involvement, we speculate that this clinical picture could be correlated with the two RET mutations and to the unusual calcitonin production. This is the first report of a men 2A case due to two mutations of the RET gene and associated with a calcitonin-producing pheochromocytoma. ( info)

5/91. Noncardiogenic pulmonary edema as the chief manifestation of a pheochromocytoma: a case report of men 2A with pedigree analysis of the RET proto-oncogene.

    Pheochromocytomas are rare neoplasias of the adrenal medulla which generally present with paroxysmal or sustained hypertension. Cardiogenic pulmonary edema is a common feature of these tumors, but few cases have been described with noncardiogenic pulmonary edema. We report a pheochromocytoma with the principle manifestation of noncardiogenic pulmonary edema and characterize a genetic lesion associated with the disorder. A 30-year-old man was admitted with abdominal pain and breathlessness. x-Ray examination of the chest revealed a massive, diffuse infiltration of the left lung without cardiomegaly. No paroxysmal blood pressure fluctuations or heart failure were evident during the entire course, and the infiltrate and dyspnea resolved in three days without inotropic or diuretic agents. serum norepinephrine and epinephrine levels were elevated twenty and fifty times above normal, respectively. The patient was ultimately diagnosed with multiple endocrine neoplasia type 2a (men 2A). Mutations in the RET proto-oncogene have been described recently in patients with men 2A. mutation analysis of selected RET exonic sequences identified a germline mutation at codon 634 in exon 11 of the RET proto-oncogene. The mutation introduces a transition encoding a non-conservative substitution from TGC (Cys) to CGC (Arg) and creates a novel restriction site recognized by HhaI. We further screened for this mutation among four of the proband's relatives by HhaI restriction analysis. One asymptomatic family member was identified who subsequently elected prophylactic total thyroid removal. Histological examination of this specimen confirmed the presence of medullary thyroid carcinoma. ( info)

6/91. The clearance of procalcitonin (PCT) during continuous veno-venous hemodiafiltration (CVVHD)

    OBJECTIVE: To evaluate the Procalcitonin (PCT) clearance during continuous veno-venous hemodiafiltration (CVVHD). DESIGN: Case report SETTING: Surgical intensive care unit.PATIENT: 51-year-old man, who had undergone total thyroidectomy about ten years before owing to multiple endocrine neoplasia 2 (men 2), suffering from multiple organ dysfunction syndrome (MODS) with acute renal failure after severe trauma caused by a traffic accident. MEASUREMENTS AND MAIN RESULT: The samplings of prefilter (afferent) and post-filter (efferent) blood and of ultradiafiltrate were 6 times performed during 24 h of CVVHD to calculate the PCT clearance of hemdiafiltration. During the first half period of CVVHD the serum PCT concentration did not decrease, though PCT had been eliminated from serum. On the other hand during the latter half period of it the serum PCT value decreased (from 46.8 ng/ml to 29.4 ng/ml) and the amount of the eliminated PCT from serum was about 100 ng per minute and its clearance was 2.3 approximately 3.4 ml/min. CONCLUSION: The CVVHD could eliminate PCT from serum. First it was brought about by the adsorption by the filter membrane and then by ultradiafiltration. ( info)

7/91. brain metastases from medullary thyroid carcinoma in a patient with multiple endocrine neoplasia type 2a.

    Medullary thyroid carcinoma (MTC) is an uncommon thyroid cancer occurring in less than 10% of patients with thyroid cancer. brain metastasis from MTC is exceedingly rare. Only six cases of brain metastasis from MTC have been reported in the literature and none had MTC as a part of multiple endocrine neoplasia (men) syndrome. We report a 42-year-old Caucasian male with men 2A who presented with neurological symptoms 25 years after total thyroidectomy with lymphadenectomy for MTC metastatic to local lymph nodes. A brain magnetic resonance imaging (MRI) showed a 4-cm cystic mass and a 1-cm nodule in the left frontal-parietal lobe in addition to a 0.8-cm cystic mass in the left frontal lobe and multiple tiny cerebellar metastatic lesions. Partial resection of the cerebral metastasis followed by whole brain radiotherapy resulted in resolution of the neurological symptoms. However, the patient had multiple systemic metastasis from the MTC and he died of systemic complications due to metastatic MTC. To our knowledge this is the first report of brain metastases from MTC in a patient with men 2A. ( info)

8/91. paraganglioma as a systemic syndrome: pitfalls and strategies.

    Tumours of the neuroendocrine system in the head and neck region are mostly paragangliomas of the glomus tympanicum or jugulare, or of the carotid body. The majority of these tumours are benign, and the coexistence of multiple paragangliomas seems to be rare. Pre-operative embolization and surgery are regarded as primary therapy for these tumours. The treatment regimen in any patient depends on age, general health, hearing status and the function of the lower cranial nerves. Several presentations are possible in which paragangliomas occur as systemic disease. 1. Paragangliomas may occur bilaterally, or, in rare cases, in multiple areas. Pre-operative bilateral angiography is of utmost importance. In case of multicentricity, it might be necessary to proceed without, or just with, unilateral surgery for preservation of adjacent structures. In surgery of jugular vein paraganglioma, we usually perform a modified transmastoidal and transcervical approach with preservation of middle-ear structures and the ossicles. As an alternative or supplement to surgery, radiotherapy or definitive embolization may be used in the treatment of paragangliomas. 2. Paragangliomas may occur as multiple endocrine neoplasia (men) syndrome combined with medullary thyroid gland carcinoma, and, facultatively, pheochromocytoma. In these cases, endocrinological examination and magnetic resonance imaging (MRI) of the adrenal region, the thorax and the neck are required for an adequate therapeutic strategy. As men may be inherited, family history should be evaluated. 3. Paragangliomas can became malignant and metastasize. Thus, cervical lymph node metastases or distant metastases may occur. We recommend the removal of all ipsilateral lymph nodes and their histological examination. ( info)

9/91. multiple endocrine neoplasia type 2a. Study of a family.

    INTRODUCTION: Pheochromocytomas (Pheo) can occur sporadically, isolated or in association with other neuroendocrine lesions. In multiple endocrine neoplasia type 2a (men-2A), Pheo is associated to medullary thyroid carcinoma (MTC) or its precursor, C-cell hyperplasia (CCH) and parathyroid hyperplasia. Genetic screening provides early diagnosis and preventive treatment. In order to validate dna analysis as a reliable method of early identification of gene carriers, we compared the results of genetic screening with clinical, biochemical, imaging and pathological findings in the members of an affected family. population AND methods: The diagnosis of a bilateral necrotic Pheo in a female patient led to the study of a family with four generations, aged 3 to 78 years (mean = 30.3 yrs). The study included a clinical examination; basal and pentagastrin stimulated calcitonin values; urinary catecholamines and their metabolites; serum calcium and a genetic study (direct sequence of PCR products from genomic dna isolated from leucocytes using specific primers in exon 11 of the RET protooncogene of chromosome 10). The radiologic study, gammagraphic study (131I-MIBG) and magnetic resonance study were performed in members with clinical suspicion of Pheo. RESULTS: Seven out of nine patients had a mutation on codon 634 of exon 11 of RET (TGC-CGC), leading to cysteine arginine substitution in the codified protein; all gene carriers had biochemical markers of MTC/CCH and four of Pheo. The Pheo patients underwent adrenalectomy (bilateral in three) and all the gene carriers underwent prophylactic thyroidectomy. The pathologic findings were: MTC in four (metastasized in one); CCH in three and parathyroid hyperplasia in one. CONCLUSIONS: Phenotypic penetration of RET mutation was 100% for MTC/CCH, but only 57% of the gene carriers had Pheo. Genetic screening allowed early prophylactic treatment in four out of seven patients; pathologic findings revealed several evolutionary stages of the disease. patients not yet showing Pheo are under close clinical and laboratory surveillance. ( info)

10/91. A RET double mutation in the germline of a kindred with FMTC.

    Activating germline mutations of the RET proto-oncogene are found in more than 90% of families with multiple endocrine neoplasia type 2a (men 2a) and familial medullary thyroid carcinoma (FMTC). The majority of patients with these hereditary tumors carry germline mutations that result in the substitution of one of five cysteine residues in exon 10 and 11. Different mutations in exons 13, 14 and 15 affecting non-cysteine residues have also been described but are considered to be rare. We now for the first time report a double mutation of the RET proto-oncogene occurring in the germline of a kindred with FMTC. Both mutations occur within the tyrosine kinase domain in exon 14 and lead to the substitution of valine 804 by methionine and arginine 844 by leucine. Since the double mutated allele cosegregated with the disease and was not identified in 200 unrelated normal probands, we conclude that they represent mutations that predispose the individual to the development of FMTC with a mild phenotype. ( info)
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