1/32. Cytogenetic and CGH studies of four neuroendocrine tumors and tumor-derived cell lines of a patient with multiple endocrine neoplasia type 1.A malignant insulinoma (LOHG-I), a carcinoid of the lung (LOHG-L), a parathyroid adenoma (LOHG-NSA), and a fibroma (LOHG-F) were obtained from a patient with multiple endocrine neoplasia type 1 (MEN1). Long-term cultures were established. Essential neurobiological properties of the cell lines were proven immunocytochemically and by electron microscopy. Molecular analysis of the germline dna showed a 4 bp deletion in exon 3 of the MEN1 gene. Cytogenetic and CGH analyses of the tumors/tumor cell lines revealed diploidy and balanced and unbalanced structural aberrations different for each tumor. chromosomes 6q21, 11q and 17q were most frequently involved in clonal structural aberrations.- - - - - - - - - - ranking = 1keywords = neuroendocrine (Clic here for more details about this article) |
2/32. Expression of vesicular monoamine transporters in endocrine hyperplasia and endocrine tumors of the oxyntic stomach.BACKGROUND: Gastric enterochromaffin-like (ECL) cells selectively express the vesicular monoamine transporter (VMAT) VMAT2, and enterochromaffin (EC) cells the VMAT1 isoform. Aims: We investigated whether VMAT isoform selection indicates the origin of endocrine hyperplasia and neoplasia from oxyntic ECL or EC cells and may be of prognostic significance in different types of gastric carcinoids. methods: Tissue from patients with chronic atrophic gastritis (CAG), Zollinger-Ellison-syndrome (ZES), gastric carcinoids and neuroendocrine carcinoma (NEC) was investigated by immunohistology and in situ hybridization. RESULTS: endocrine cells forming diffuse, linear, and micronodular hyperplasia in CAG and ZES, as well as oxyntic microcarcinoids expressed both VMAT2 and chromogranin a (CgA) but neither VMAT1 nor serotonin. In five of six sporadic carcinoids VMAT2 and CgA but not VMAT1 were detected. One carcinoid was copositive for VMAT1 and serotonin but negative for VMAT2. Electron microscopy confirmed the VMAT2-positive tumors as ECLoma and the VMAT1-immunoreactive carcinoid as EComa. CONCLUSIONS: VMAT2 and VMAT1 are reliable markers for differentiation of gastric endocrine hyperplasia and neoplasia from ECL and EC cells, respectively. The significance of VMAT2 and VMAT1 as prognostic markers lies in the relatively poor prognosis for EComa compared to ECLoma, characterized by VMAT2 positivity. The absence of both VMAT2 and VMAT1 in NEC may indicate poor prognosis.- - - - - - - - - - ranking = 0.25329022117005keywords = neuroendocrine, carcinoma (Clic here for more details about this article) |
3/32. multiple endocrine neoplasia type 1: atypical presentation, clinical course, and genetic analysis of multiple tumors.multiple endocrine neoplasia type 1 (MEN1) is characterized by the development of endocrine tumors of the parathyroid and pituitary glands, pancreas, and duodenum. Less frequently occurring tumors associated with MEN1 include non-endocrine tumors such as lipomas and angiofibromas. An increased incidence of thyroid neoplasms, leiomyomas, adrenal cortical hyperplasia, hepatic focal nodular hyperplasia, and renal angiomyolipoma has been noted in the MEN1 population. The pathogenesis of non-neuroendocrine tumors in MEN1 is unknown. We report a complex clinical course and a detailed morphologic and genetic analysis of a series of tumors that developed in a patient with MEN1. All tumors were microdissected and analyzed for loss of heterozygosity of the MEN1 gene. A germline mutation of the MEN1 gene was detected, and deletions of the MEN1 gene were consistently detected in multiple neuroendocrine tumors involving the parathyroid glands and the pancreas and a hepatic neuroendocrine tumor metastasis, as predicted by Knudson's "two hit" hypothesis. Two hits of the MEN1 gene were also detected in esophageal leiomyoma tissue, suggesting that tumorigenesis was directly related to the patient's underlying MEN1. In contrast, follicular thyroid adenoma, papillary thyroid carcinoma, hepatic focal nodular hyperplasia, and adrenal cortical hyperplasia consistently showed retained heterozygosity of the MEN1 gene with flanking markers and an intragenic marker. Therefore, these tumors appear to develop along pathogenetic pathways that are different from classical MEN1-associated tumors.- - - - - - - - - - ranking = 0.75329022117005keywords = neuroendocrine, carcinoma (Clic here for more details about this article) |
4/32. Overview of chronic diarrhea caused by functional neuroendocrine neoplasms.Eight different neoplastic disorders can cause chronic diarrhea attributable to humoral-mediated diarrhea. These include pancreatic endocrine tumor (PET) syndromes (gastrinomas, VIPomas, glucagonomas, somatostatinomas, PET's releasing calcitonin), carcinoid syndrome, medullary thyroid cancer, and systemic mastocytosis. Because these disorders are an uncommon cause of all chronic diarrheas (<1%), they are not often considered in the differential diagnosis, leading to a delay in diagnosis. This is problematic not only because all are treatable, but also because the neoplasm is frequently malignant. In this article, the characteristics and pathogenesis of the diarrhea, important clinical and diagnostic laboratory features, and treatment of each disorder are briefly reviewed, with an emphasis on recent insights.- - - - - - - - - - ranking = 1keywords = neuroendocrine (Clic here for more details about this article) |
5/32. Thymic carcinoid and parathyroid hyperplasia detection with 99mTc-MIBI men type 1.We report a case of a 35-year-old male, with a history of diarrhea, renal lithiasis with frequent expulsions of calculus and hypercalcemia during the last 2 years. The patient was studied and diagnosed with a multiple endocrine neoplasia type I (men I), familiar (mother with men I). A scintigraphic study with 99mTc-MIBI was performed in order to localize hyperfunctioning parathyroid glands because of biochemical diagnosis of primary hyperparathyroidism. Double phase 99mTc-MIBI scan detected one hyperfunctioning parathyroid gland and a large anterior mediastinal mass. Subsequent, plain radiograph and CT of the chest showed a soft-tissue mass in that localization. Punch biopsy of the lesion guided by CT revealed malignant cells of neuroendocrine tumor. The tumor was removed and histologically confirmed as a carcinoid within a thymus in a men type I syndrome. men I patients can benefit from the examination with this agent which can potentially localize not only parathyroid endocrine pathology but also unknown associated tumors.- - - - - - - - - - ranking = 0.25keywords = neuroendocrine (Clic here for more details about this article) |
6/32. chromogranin a expression in hepatocellular carcinoma in a patient with germline MEN1 gene mutation.Hepatocellular carcinoma (HCC) was found in a patient with multiple endocrine neoplasia type 1 (men 1). The intriguing finding was that the HCC in the patient was positively stained for chromogranin a (CgA), a cellular marker for endocrine and neuroendocrine tumors. The patient had a pancreas endocrine tumor and type C hepatitis, that made pathological diagnosis of the origin of the tumor complicated.- - - - - - - - - - ranking = 0.26645110585024keywords = neuroendocrine, carcinoma (Clic here for more details about this article) |
7/32. A genotypic and histopathological study of a large Dutch kindred with hyperparathyroidism-jaw tumor syndrome.Familial primary hyperparathyroidism is the main feature of 2 familial endocrine neoplasia syndromes: multiple endocrine neoplasia type 1 (men 1) and hyperparathyroidism-jaw tumor syndrome (HPT-JT). The latter is a recently described syndrome that has been associated with ossifying fibroma of the jaw and various types of renal lesions, including benign cysts, Wilms' tumor, and hamartomas. To further illustrate the natural history of this syndrome, we describe a large, previously unreported Dutch kindred in which 13 affected members presented with either parathyroid adenoma or carcinoma; in 5 affected individuals, cystic kidney disease was found. Additionally, pancreatic adenocarcinoma, renal cortical adenoma, papillary renal cell carcinoma, testicular mixed germ cell tumor with major seminoma component, and Hurthle cell thyroid adenoma were also identified. Linkage analysis of the family using MEN1-linked microsatellite markers and mutation analysis excluded the involvement of the MEN1 gene. Using markers from the HPT-JT region in 1q2531, cosegregation with the disease was found, with a maximum logarithm of odds score of 2.41 obtained for 6 markers using the most conservative calculation. Meiotic telomeric recombination between D1S413 and D1S477 was identified in 3 affected individuals, and when combined with previous reports, delineated the HPT-JT region to 14 centimorgan. Combined comparative genomic hybridization and loss of heterozygosity data revealed complex genetic abnormalities in the tumors, suggesting different possible genetic mechanisms for the disease. In conclusion, we report a family with hyperparathyroidism linked to chromosome 1q, and exhibiting several types of renal and endocrine tumors that have not been previously described.- - - - - - - - - - ranking = 0.0098706635101416keywords = carcinoma (Clic here for more details about this article) |
8/32. A newly recognized germline mutation of MEN1 gene identified in a patient with parathyroid adenoma and carcinoma.We report on a patient with primary hyperparathyroidism, owing to the concurrence of parathyroid adenoma with carcinoma, who had a newly recognized germline mutation of the multiple endocrine neoplasia type 1 gene (MEN1 gene). The patient underwent total parathyroidectomy, and histological examination revealed parathyroid carcinoma and multiple adenoma of the other three glands. Genetic analysis revealed a newly recognized heterozygous germline mutation (842delC, exon 4) of the MEN1 gene. Both imaging studies and laboratory data showed no evidence of MEN1 in the patient. Four family members--three sisters and one daughter--had neither clinical features of MEN1 nor genetic evidence of the MEN1 gene. This is the first report of a germline mutation of the MEN1 gene found in a patient who exhibited the concurrence of parathyroid adenoma with carcinoma, suggesting that long-term hyperactivity of the parathyroids may result in the formation of carcinoma.- - - - - - - - - - ranking = 0.026321769360378keywords = carcinoma (Clic here for more details about this article) |
9/32. Multiple endocrine neoplasia (men)--an overview and case report--patient with sporadic bilateral pheochromocytoma, hyperparathyroidism and marfanoid habitus.The multiple endocrine neoplasia syndromes are divided into two categories: men type I and men type II. The men type II syndrome is further divided into men IIa and men IIb. The syndromes are characterized by benign and malignant changes in two or more endocrine organs, as well as incidental changes in nervous, muscular and connective tissue. Two main forms can be distinguished: the men-I syndrome with hyperplasia of the parathyroid gland, accompanied by islet cell tumor and pituitary adenoma; the men-II syndrome with medullary thyroid carcinoma in combination with bilateral pheochromocytoma and hyperplasia of the parathyroid gland (men IIa), while type IIb is characterized by the additional appearance of neurocutaneous manifestations without primary hyperparathyroidism. Characteristics shared by these syndromes include the involved cell type, most of the tumors are composed of one or more specific polypeptide- and biogenic amine-producing cell types (APUD--amine precursor uptake and decarboxylation). The second characteristic is the increased incidence in certain families. The hereditary component is autosomal dominant with variable expression but high penetrance. Mechanisms of tumorigenesis differ in these syndromes. While men I is caused by an inherited mutation of a tumor suppressor gene, menin, located on the long arm of chromosome 11, men II is caused by activation of the RET proto-oncogene. We have reported the case of a young man exhibiting bilateral pheochromocytoma. In addition, the patient showed mild primary hyperparathyroidism and marfanoid habitus, all these stigmata usually being part of the men-II syndrome. Although this described patient showed a phenotypic mixture of the men-IIa and men-IIb syndrome, the genetic analysis for men II and von-Hippel-Lindau gene did not reveal any pathologic mutations, the endocrine disorders described here are not related to multiple endocrine neoplasia syndromes.- - - - - - - - - - ranking = 0.0032902211700472keywords = carcinoma (Clic here for more details about this article) |
10/32. Neuroendocrine carcinoma of the sphenoid sinus: a case report.The presentation of a neuroendocrine carcinoma in the paranasal sinuses is extremely rare. Until now only 25 cases have been reported in the literature. We report a case of a 65-year-old male with an atypical carcinoid of the sphenoid sinus which seemed to be associated with multiple endocrine neoplasia type 1 (men 1). To the best of our knowledge this is the first report on an atypical carcinoid in the sphenoid sinus.- - - - - - - - - - ranking = 0.26645110585024keywords = neuroendocrine, carcinoma (Clic here for more details about this article) |
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