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* Plasma cell granuloma (PCG) is characterized by proliferation of polyclonal plasma cells with associated fibrosis and is often considered part of the heterogeneous group of inflammatory myofibroblastic tumors (IMTs). The thyroid is rarely affected by PCG. A patient having PCG associated with Hashimoto thyroiditis (HT) prompted our literature search that revealed 18 cases of PCG, 55% (n = 10) of which occurred together with HT. The etiopathogenesis of PCG is unknown and there is no specific treatment except surgical excision for compressive symptoms. This entity has an excellent prognosis with no evidence of recurrence or metastasis. Lesions of the thyroid with infiltrating plasma cells include HT, fibrous variant of HT, plasmacytoma, plasma cell myeloma, Riedel thyroiditis, IgG4 (immunoglobulin G4)-related disease, IMT, and PCG. Inflammatory myofibroblastic tumor has ALK gene rearrangements and is considered a neoplasm as opposed to PCG, which is a reactive polyclonal plasma cell proliferation. We believe IMT and PCG are distinct entities and consensus definitions are required for avoiding confusion in the literature. doi: 10.5858/arpa.2017-0068-RS, Plasma cell granuloma (PCG) is a pseudotumor-like condition characterized by polyclonal proliferation of plasma cells. Historically, PCGs are considered within the spectrum of inflammatory myofibroblastic tumors (IMTs) and, therefore, we [...]

Inactivation of tumor suppressor gene p16 may play an important role in the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA). Hypermethylation of p16 gene promoter is an important mechanism inactivating p16. However, the mechanisms of p16 hypermethylation in EA are not known. Therefore, we examined whether acid increases methylation of p16 gene promoter and whether NADPH oxidase NOX5-S mediates acid-induced p16 hypermethylation in a Barrett's cell line BAR-T and an EA cell line OE33. We found that NOX5-S was present in BAR-T and OE33 cells. Acid-induced increase in H202 production and cell proliferation was significantly reduced by knockdown of NOX5-S. Exogenous H202 remarkably increased p16 promoter methylation and cell proliferation. In addition, acid treatment significantly increased p16 promoter methylation and decreased p16 mRNA level. Knockdown of NOX5-S significantly increased p16 mRNA, inhibited acid-induced downregulation of p16 mRNA, and blocked acid-induced increase in p16 methylation and cell proliferation. Conversely, overexpression of NOX5-S significantly decreased p16 mRNA and increased p16 methylation and cell proliferation. In conclusion, NOX5-S is present in BAR-T cells and OE33 cells and mediates acid-induced [H.sub.2][O.sub.2] production and cell proliferation. NOX5-S is also involved in acid-induced hypermethylation of p16 gene promoter and downregulation of p16 mRNA. It is possible that acid reflux present in BE patients may activate NOX5-S and increase production of reactive oxygen species, which in turn increase p16 promoter methylation, downregulate p16 expression, and increase cell proliferation, thereby contributing to the progression from BE to EA. Barrett's esophagus; reactive oxygen species; acid; hydrogen peroxide; cell proliferation doi: 10.1152/ajpgi.00186.2010.

Byline: Kyle. Brownback, Joseph. Renzulli, Ronald. DeLellis, James. Myers Five cases of small-cell carcinoma (SCC) of prostate were identified, at the Rhode Island Hospital and the Miriam Hospital from 1984 [...]

* Context.--Prophylactic thyroidectomies are increasingly performed on patients at risk for developing medullary thyroid carcinoma (MTC); consequently, pathologists are more commonly encountering these specimens in routine practice. Objective.--To describe the detailed clinicopathologic features of prophylactic thyroidectomies for medullary carcinoma. Design.--We present a retrospective series of 42 prophylactic thyroidectomies for MTC performed for one or more of the following: family history of multiple endocrine neoplasia (MEN) or MTC, elevated serum calcitonin level, or detection of a RET proto-oncogene mutation. Results.--Patients included 22 men and 20 women (mean age, 26.2 years). Among those with known RET proto-oncogene mutations, affected sites included exons 10, 11, 14, and 16. In 93% (n = 39) of cases, either C-cell hyperplasia (n = 36), medullary microcarcinoma (MMC; n = 29), or medullary macrocarcinoma (n = 1) was found. C-cell hyperplasia was often multifocal (n = 30) and bilateral (n = 23) and included both nonnodular and nodular patterns. A total of 94% of C-cell hyperplasia cases and all MMC cases were microscopically detectable using hematoxylin-eosin stains. The MMCs were characterized by a complex microarchitectural pattern with a desmoplastic stromal response (n = 29) and focal amyloid deposition (n = 12). Most MMCs exhibited a solid pattern (n = 24) of round, polygonal, spindled, or plasmacytoid-shaped cells. Only 1 case of MMC showed evidence of metastatic disease to a pretracheal lymph node. Conclusions.--Based upon our clinicopathologic findings and review of the literature, we conclude that thyroidectomies in at-risk patients are very frequently associated with C-cell hyperplasia and/or MMC; however, the clinical prognosis for these patients is very good., Medullary thyroid carcinoma (MTC) is an uncommon thyroid malignancy of C-cell derivation representing approximately 3% to 12% of all thyroid cancers. (1-3) It has a propensity for metastasis to regional [...]

Context.--Primary hyperparathyroidism (P-HPT) is one of the most common of all endocrine disorders. Eighty percent to 85% of cases are due to parathyroid adenomas while hyperplasia and carcinoma account for 10% to 15% and less than 1%, of cases, respectively. The past decade has witnessed remarkable advances in the understanding of the molecular basis of parathyroid hyperplasia and neoplasia. Additionally, imaging studies and the development of the intraoperative assay for parathyroid hormone have transformed the diagnosis and management of patients with these disorders. Objective.--To review the pathology of parathyroid lesions associated with P-HPT, their molecular and genetic bases, including heritable hyperparathyroidism syndromes, and their clinical diagnosis and management. Data Sources.--Review of pertinent epidemiology, pathology, radiology, and surgery literature on the diagnosis, classification, and treatment of P-HPT. Conclusions.--Although heritable causes of P-HPT in cluding multiple endocrine neoplasia 1 and 2A and hyperparathyroidism--jaw tumor syndrome account for a minority of cases of P-HPT, advances in the characterization of the affected genes have provided insights into the genetic basis of sporadic parathyroid neoplasms. Alterations in cyclin D1 and loss of heterozygosity of chromosome 11q in adenomas and hyperplasias have provided support for clonality of these lesions. Parafibromin, the protein product of the HRPT2 gene responsible for hyperparathyroidism--jaw tumor syndrome, has been implicated in the development of sporadic parathyroid carcinomas and loss of immunohistochemical expression of this protein has been suggested to be of value in making the diagnosis of parathyroid carcinoma. Sestamibi scanning and ultrasound have revolutionized the planning of surgical approaches and the intraoperative parathyroid hormone assay has become the standard in guiding completion or extension of surgery. (Arch Pathol Lab Med. 2008;132:1251-1262), The term primary hyperparathyroidism (P-HPT) refers to the inappropriate or unregulated overproduction of parathyroid hormone (PTH) leading to abnormal calcium homeostasis. High levels of PTH lead to increased renal resorption [...]

The tumor microenvironment regulates tissue development and homeostasis, and its dysregulation contributes to neoplastic progression. Increased expression of type X collagen α‐1 (ColXα1) in tumor‐associated stroma correlates with poor pathologic response to neoadjuvant chemotherapy in estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2)‐positive breast cancers. Evaluation of ColXα1 expression patterns suggests a potential connection with elastin fibers. To investigate the possible interaction between ColXα1 and elastin, we evaluated the expression of ColXα1 in relation to elastin fibers in normal breast tissue, ductal carcinoma in situ, and invasive breast carcinomas at cellular and subcellular levels. Our findings demonstrate that ColXα1 colocalizes with elastin in invasive breast cancer‐associated stroma by immunohistochemistry, immunofluorescence, and electron microscopy. In 212 invasive breast carcinomas, this complex was aberrantly and selectively expressed in tumor extracellular matrix in 79% of ER+/HER2−, 80% of ER+/HER2+, 76% of ER−/HER2+, and 58% of triple negative breast cancers. In contrast, ColXα1 was generally absent, while elastin was present perivascularly in normal breast tissue. ColXα1 and elastin were coexpressed in 58% of ductal carcinoma in situ (DCIS) in periductal areas. In mass‐forming DCIS with desmoplastic stroma, the complex was intensely expressed in periductal areas as well as within the tumor‐associated stroma in all cases. Our data suggest that the breast carcinoma neoplastic process may involve aberrant expression of ColXα1 and elastin in the tumor microenvironment emerging early at the DCIS stage. Enrichment of these complexes in tumor‐associated stroma may represent a stromal signature indicative of intrinsic differences between breast cancers. These findings shed light on investigation into the role of aberrant collagen complex expression in tumorigenesis and tumor progression which may be leveraged in therapeutic and theranostic applications. [ABSTRACT FROM AUTHOR]

* Water-clear cell hyperplasia is a rare but well-documented cause of primary hyperparathyroidism. Parathyroid adenomas of the water-clear cell type are exceptionally rare, and only 2 cases have been reported. We describe a patient with synchronous water-clear cell double parathyroid adenomas, an entity that has not previously been reported. In our case, the enlarged superior parathyroid glands were completely replaced by water-clear cells, with only a minute rim of extracapsular, histologically unremarkable parathyroid tissue. The inferior parathyroid glands were grossly unremarkable, and incisional biopsy specimens were histologically normal (no foci of water-clear cells were identified). The findings in this case are most consistent with the diagnosis of double adenomas of the water-clear cell type. We acknowledge that despite molecular proof of monoclonality of the 2 lesions, it is not possible to entirely exclude the possibility that this unusual case could be due to asymmetric hyperplasia. (Arch Pathol Lab Med. 2001;125:256-259), A Hitherto Uncharacterized Entity? Water-clear cell (WCC) hyperplasia is a rare but well-documented cause of primary hyperparathyroidism. In classic WCC hyperplasia, all 4 parathyroid glands have finely vacuolated cells, although [...]