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Benign Adenomas (benign + adenoma)
Selected AbstractsSurveillance for Early Detection of Aggressive Parathyroid Disease: Carcinoma and Atypical Adenoma in Familial Isolated Hyperparathyroidism Associated With a Germline HRPT2 Mutation,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2006Thomas G Kelly Abstract Familial hyperparathyroid syndromes involving mutations of HRPT2 (also CDC73), a tumor suppressor, are important to identify because the relatively high incidence of parathyroid malignancy associated with such mutations warrants a specific surveillance strategy. However, there is a dearth of reports describing experience with surveillance and early detection informed by genetic insight into this disorder. Introduction: Familial isolated hyperparathyroidism (FIHP) is a rare cause of parathyroid (PT) tumors without other neoplasms or endocrinopathies. Germline mutations in CASR, MEN1, and rarely, HRPT2 have been identified in kindreds with FIHP. HRPT2 mutations may be enriched in FIHP families with PT carcinoma, underscoring the importance of identifying causative mutations. Materials and Methods: A 13-year-old boy, whose father had died of PT carcinoma, developed primary hyperparathyroidism. A left superior PT mass was identified by ultrasonography and removed surgically. Aggressive histological features of the boy's tumor included fibrous trabeculae, mitoses, and microscopic capsular infiltration. Two years later, under close biochemical surveillance, primary hyperparathyroidism recurred 5 months after documentation of normocalcemia and normal parathyroid status. Ultrasound and MRI identified a newly enlarged right superior PT gland but indicated no recurrent disease in the left neck. Histologic features typical of a benign adenoma were evident after surgical extirpation of the gland. Results: Leukocyte DNA analysis revealed a frameshift mutation in exon 2 of HRPT2. The initial tumor manifested the expected germline HRPT2 mutation, plus a distinct somatic frameshift mutation, consistent with the Knudson "two hit" concept of biallelic inactivation of a classic tumor suppressor gene. Genetic screening of the patient's 7 asymptomatic and previously normocalcemic siblings revealed three with the same germline HRPT2 mutation. One of the siblings newly identified as mutation-positive was noted to be hypercalcemic at the time of the genetic screening. He was found to have a PT adenoma with aggressive features. Two of the five children of another mutation-positive sibling also carry the same HRPT2 mutation. Conclusions: Despite the reported rarity of HRPT2 mutations in FIHP, a personal or family history of PT carcinoma in FIHP mandates serious consideration of germline HRPT2 mutation status. This information can be used in diagnostic and management considerations, leading to early detection and removal of potentially malignant parathyroid tumors. [source] Diagnosis and treatment of small follicular thyroid carcinomas,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 6 2010T. Clerici Background: Follicular thyroid microcarcinomas (mFTCs) of 10 mm or less in size rarely manifest clinically and their clinical significance is controversial. This study assessed their characteristics and incidence, and analysed treatment modalities used for mFTC. Methods: Members of the German Association of Endocrine Surgeons were asked to review patients with mFTC operated on between 1990 and 2005. Results: Data for 90 patients from 26 institutions were reported. Histopathological slides were available for re-evaluation in 35 patients. Most initial diagnoses had to be revised because of incorrect size assessment or incorrect diagnosis (benign adenoma, papillary thyroid carcinoma (PTC), follicular variant of PTC). The diagnosis of mFTC was confirmed in only four patients. As a result of the incorrect histopathological diagnosis, unnecessary completion thyroidectomy and radioiodine ablation were performed in 17 and 20 patients respectively. The incidence of mFTC was calculated to be 0·12 per million population per year. Conclusion: mFTC is exceptionally rare. Such tumours are overdiagnosed, resulting in unnecessary treatment associated with avoidable morbidity. Histopathological re-evaluation by an experienced pathologist is recommended before embarking on further treatments when a diagnosis of mFTC is made. Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Human colon cancer epithelial cells harbour active HEDGEHOG-GLI signalling that is essential for tumour growth, recurrence, metastasis and stem cell survival and expansionEMBO MOLECULAR MEDICINE, Issue 6-7 2009Frédéric Varnat Abstract Human colon cancers often start as benign adenomas through loss of APC, leading to enhanced ,CATENIN (,CAT)/TCF function. These early lesions are efficiently managed but often progress to invasive carcinomas and incurable metastases through additional changes, the nature of which is unclear. We find that epithelial cells of human colon carcinomas (CCs) and their stem cells of all stages harbour an active HH-GLI pathway. Unexpectedly, they acquire a high HEDGEHOG-GLI (HH-GLI) signature coincident with the development of metastases. We show that the growth of CC xenografts, their recurrence and metastases require HH-GLI function, which induces a robust epithelial-to-mesenchymal transition (EMT). Moreover, using a novel tumour cell competition assay we show that the self-renewal of CC stem cells in vivo relies on HH-GLI activity. Our results indicate a key and essential role of the HH-GLI1 pathway in promoting CC growth, stem cell self-renewal and metastatic behavior in advanced cancers. Targeting HH-GLI1, directly or indirectly, is thus predicted to decrease tumour bulk and eradicate CC stem cells and metastases. [source] Detectable BRAF mutation in serum DNA samples from patients with papillary thyroid carcinomasHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2010Tony C. Y. Chuang MD Abstract Background. An activating point mutation of the BRAF oncogene results in a V600E amino acid missense mutation found in a majority of papillary thyroid carcinomas (PTC). Methods. In this study, 28 matched tumor and serum samples obtained from patients with both benign and malignant thyroid disorders were analyzed for BRAF mutation using a gap-ligase chain reaction technique. Results. The BRAF mutation was absent in tumor DNA samples obtained from patients with benign adenomas, follicular neoplasms or carcinoma, and thyroid lymphoma. In contrast, 5 of 14 PTC tumors were positive for the BRAF mutation. Moreover, 3 of 14 patients with PTC were positive for BRAF mutation in serum and tumor. Of these 3 patients, 2 had lymph node metastasis and 2 had PTC in background of the Hashimoto's thyroiditis. Conclusions. The detection of free circulating mutant BRAF in patients with PTC is possible and future studies are warranted to determine its clinical significance. © 2009 Wiley Periodicals, Inc. Head Neck, 2010 [source] Characteristics of hepatocellular carcinoma in a murine model of alpha-1-antitrypsin deficiencyHEPATOLOGY RESEARCH, Issue 6 2010Nancy Y. Marcus Aim:, Individuals with homozygous (ZZ) alpha-1-antitrypsin (,1AT) deficiency are at an increased risk for liver damage, cirrhosis and hepatocellular carcinoma (HCC). The transgenic PiZ mouse, expressing the human ,1AT mutant Z gene, is a valuable model for this disease. We studied PiZ mice in order to identify and characterize mechanisms involved in the development of HCC. Methods:, Tumor incidence and histology were studied, gene expression levels were surveyed with microarrays, RNA quantified with quantitative real time polymerase chain reaction and protein levels determined with immunoblots and immunohistochemistry. Results:, By 16,19 months of age, approximately 69% of the PiZ mice had developed tumors. HCC was present with no evidence of benign adenomas as pre-cancerous lesions. Tumors showed abnormal mitochondria, variable levels of steatosis, globular inclusions of ,1AT mutant Z protein and metastases. PiZ mice that subsequently developed liver tumors had higher serum levels of ,1AT mutant Z protein than those that did not develop tumors. Cyclin D1, a cell cycle protein, was upregulated in PiZ livers without tumors compared to Wt. cFOS, a component of AP-1 that may be involved in transforming cells and MCAM, an adhesion molecule likely involved in tumorigenesis and metastases, were elevated in tumors compared with livers without tumors. Conclusion:, In the PiZ model, many of the histological characteristics of HCC recapitulated features seen in human HCC, whether from individuals with homozygous ZZ liver disease or from unrelated causes in individuals that were not homozygous ZZ. The accumulation of mutant Z protein altered the regulation of several genes driving proliferation and tumorigenesis. [source] Progressive up-regulation of genes encoding DNA methyltransferases in the colorectal adenoma-carcinoma sequenceMOLECULAR CARCINOGENESIS, Issue 9 2007Wolfgang M. Schmidt Abstract Epigenetic silencing is a prominent feature of cancer. Here, we investigated the expression of DNA demethylase and three DNA methyltransferases during colorectal tumorigenesis comparing the genes encoding DNA methyltransferases 1 (DNMT1), 3A, and 3B (DNMT3A and DNMT3B) with methyl-CpG binding domain protein 2 (MBD2), recently described as the only active DNA demethylase. Total RNA isolated from normal colonic mucosa (n,=,24), benign adenomas (n,=,18), and malignant colorectal carcinomas (n,=,32) was analyzed by reverse transcriptase-PCR with subsequent quantification by capillary gel electrophoresis. In contrast to MBD2, expression of DNMT1 and DNMT3A increased in parallel to the degree of dysplasia, with significant overexpression in the malignant lesion when compared with mucosa or with benign lesions (DNMT1). Pairwise comparisons between tumors and matched, adjacent healthy mucosa tissue (n,=,13) revealed that expression of all three genes encoding DNA methyltransferases increased by two- to three-fold. Our data suggest a relevant role of the DNA methyltransferases during colorectal tumorigenesis. This increase is not counterbalanced by enhanced expression of the demethylating component MBD2. As a consequence, epigenetic regulation in the adenoma-carcinoma sequence may be driven by increased methylating activity rather than suppressed demethylation. © 2007 Wiley-Liss, Inc. [source] Osteopontin stimulates invasion of NCI-h295 cells but is not associated with survival in adrenocortical carcinoma,THE JOURNAL OF PATHOLOGY, Issue 2 2009Dirk Weismann Abstract Gene array studies indicated that osteopontin (OPN) mRNA is highly expressed in adrenocortical carcinomas (ACCs). OPN enhances invasiveness, proliferation, and metastasis formation, and is associated with poor survival in some malignant diseases. Integrin ,v,3 has been shown to mediate OPN effects on invasion. In this study, we demonstrated OPN and integrin ,v,3 expression in normal adrenal glands and benign adenomas, with staining seen exclusively in adrenocortical cells as well as even stronger staining in ACC. Western blot analysis confirmed overexpression of OPN in ACC (p < 0.01). With Matrigel invasion assays, we have shown that OPN greatly stimulates the invasiveness of NCI-h295 cells (>six-fold increase, p < 0.001). Transfection with integrin ,v,3 further increased invasiveness after OPN stimulation (p < 0.001). This increase was reversed by the addition of an anti-integrin ,3 antibody, indicating a functional relationship of OPN and integrin ,v,3 in ACC. With tissue arrays, we confirmed high OPN expression in 147 ACC samples. However, no association with survival was seen in Kaplan-Meier analysis including 111 patients with primary tumours graded for OPN staining and follow-up data available. In conclusion, our in vitro data indicate that OPN and integrin ,v,3 may act as a functional complex facilitating the invasiveness of adrenocortical tumours. This relationship remains of relevance to our understanding of carcinogenesis, but further studies are needed to address the physiological and pathological function of OPN in adrenal tissue. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] | ||||||||||