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G M Groisman

Publications and source records attributed to G M Groisman.

At least 19 recordsLinked to original sources
PubMed2006

Fibroblastic polyp of the colon: clinicopathological analysis of 10 cases with emphasis on its common association with serrated crypts.

AIMS: To describe the clinical and pathological features of 10 further cases of fibroblastic polyps (FP), a recently described, distinctive type of colorectal mucosal polyp. METHODS AND RESULTS: The patients were seven women and three men with ages ranging from 44 to 63 years. The lesions ranged in size from 2 to 4 mm. Eight of the polyps were located in the sigmoid colon. Five cases were associated with hyperplastic polyps. Histologically, FP displayed bland, plump spindle cells with oval nuclei arranged as bundles parallel to the surface or as haphazardly orientated sheets with a focal periglandular or perivascular concentric arrangement. Eight polyps represented mixed fibroblastic/hyperplastic polyps as they contained serrated (hyperplastic) crypts. Immunohistochemically, all cases were positive for vimentin and negative for desmin, smooth-muscle actin, h-caldesmon, S100 protein, c-Kit, epithelial membrane antigen, cytokeratin AE1/3, CD34, CD68, COX-2, and factor XIIIa. Ultrastructural examination supported the fibroblastic nature of the tumour cells. CONCLUSIONS: FP is a distinctive type of benign mucosal colorectal polyp characterized by its distal location, small size, frequent association with hyperplastic polyps, distinct morphological appearance and typical immunonegativity for markers of specific differentiation. FP with serrated crypts (mixed fibroblastic/hyperplastic polyp) represents a frequent variant of this lesion. Pathologists should recognize FP and discriminate it from other types of colorectal polyps.

Adult↗
PubMed2000

Multinucleated stromal cells of the anal mucosa: a common finding.

AIMS: To document the presence, morphology, immunophenotype and ultrastructure of multinucleated stromal cells within the anal mucosa and to discuss possible pathogenetic mechanisms for this occurrence. METHODS AND RESULTS: Multiple sections of normal anal mucosa from 30 abdominoperineal resection specimens were analysed by light microscopic, electron microscopic and immunohistochemical methods. Multinucleated stromal cells were found in 22 cases (73%). They contained two to five nuclei, arranged in a linear fashion or in a rosette or grape-like pattern. They stained positive for vimentin and negative for actin, desmin and oestrogen/progesterone receptors. Ultrastructural examination confirmed their fibroblastic lineage. Mast cells were frequently observed in the immediate vicinity of mono- and multinucleated cells. CONCLUSIONS: Multinucleated stromal cells are a common occurrence in the normal anal mucosa. They should not be misinterpreted as neoplastic cells. Mast cells may play a role in their morphogenesis.

Aged↗
PubMed2000

Pleomorphic hyalinizing angiectatic tumor of soft parts: immunohistochemical study including the expression of vascular endothelial growth factor.

We report morphologic, flow cytometric, and immunohistochemical findings in two cases of pleomorphic hyalinizing angiectatic tumor of soft parts. Both patients were middle-aged women with subcutaneous lesions located in the lower extremity. The tumors consisted of sheets of spindled and pleomorphic cells with frequent intranuclear pseudoinclusions associated with clusters of ectatic vessels surrounded by prominent perivascular hyaline material. Numerous, nonhyalinized vessels were also present, mostly in the peripheral areas of the lesions. Some of these vessels had their walls permeated by numerous small capillaries. Immunostaining for vascular endothelial growth factor (VEGF), a secreted protein that has been implicated in tumor-associated angiogenesis, demonstrated positive staining in both tumoral and endothelial cells. Tumor cells were also reactive to vimentin and CD34. Focal positivity for CD99 and factor XIIIa was also present. Flow cytometry yielded a diploid DNA histogram with S-phase fraction of 7%. Our findings corroborate those from previously reported cases. They further suggest that angiogenesis and the angiogenic factor VEGF may play a role in the development of this peculiar tumor.

12E7 Antigen↗
PubMed2000

Enterocyte apoptosis and proliferation are increased in microvillous inclusion disease (familial microvillous atrophy).

Microvillous inclusion disease (MID) is characterized by diffuse villous atrophy without inflammatory changes. While increased apoptosis has been related to mucosal flattening in celiac disease, the role of apoptosis in the pathogenesis of MID is unknown. The aim of this study was to assess the rates of apoptosis and cell proliferation in MID and to compare them with those of normal controls and celiac disease. Small intestinal biopsies from 5 infants with MID, 10 children with normal villous architecture, and 10 children with untreated celiac disease were stained with the terminal uridine deoxynucleotidyl nick end labeling (TUNEL) method to assess apoptotic activity, and with Ki-67 immunohistochemistry to assess cellular proliferation. TUNEL and Ki-67 positive enterocytes were counted in a minimum of 20 well oriented half crypts per section. The percentage of apoptotic cells per crypt (apoptotic index) in normal, MID, and celiac biopsies was 0.03 +/- 0.01%, 0.08 +/- 0.08%, and 0.16 +/- 0.3%, respectively. Significant differences were found between normal and MID, and between normal and celiac cases. The percentage of Ki-67 positive cells per crypt (proliferation index) in normal, MID, and celiac cases was 14 +/- 2.5%, 28 +/- 9.2%, and 56 +/- 14%. Significant differences were found between the 3 groups. In conclusion, (1) enterocyte apoptosis and proliferation are increased in MID; (2) apoptosis appears to be an important factor of cell loss and may be, at least in part, responsible for villous atrophy in MID; and (3) crypts in MID are hyperplastic and not hypoplastic. HUM PATHOL 31:1404-1410.

Apoptosis↗
PubMed1999

Microcalcifications in the anterior pituitary gland of the fetus and the newborn: a histochemical and immunohistochemical study.

Calcified concretions are a normal and constant finding in the anterior pituitary gland of fetuses and newborns. Their light and electron microscopic characteristics have been recently reported by the authors. In this study, undecalcified and decalcified sections from 20 neonatal and 60 fetal anterior pituitary glands were studied by histochemical and immunohistochemical methods to further clarify their nature and mechanism of formation. All the glands revealed homogeneous and/or laminar calcifications located either within the interstitium or follicular structures. They were composed of a diastase-resistant periodic acid-Schiff-positive carbohydrate-rich matrix. The Feulgen method for DNA was negative. Their core frequently reacted to Alcian blue and epithelial membrane antigen (EMA). EMA also stained the apical membranes of adjacent epithelial cells. Other immunostains (vimentin, keratin, and pituitary hormones) were negative. The positive staining for Alcian blue and EMA and the negative staining with the Feulgen method for DNA suggest that the core of the calcifications consists of acidic mucosubstances and EMA-positive proteinaceous material previously secreted by viable pituitary cells. The EMA-negative periphery of the concretions probably develops from further extracellular peripheral mineralization that leads to larger, sometimes laminated psammoma bodies. The occurrence of pituitary calcifications in states of adult physiological and pathological hyperprolactinemia suggests that the marked proliferation of lactotrophs occurring during the fetal life play an important role in the pathogenesis of the fetal and neonatal concretions.

Biomarkers↗
PubMed1998

Metastatic follicular thyroid carcinoma to the maxilla.

We present a unique case of metastatic follicular thyroid carcinoma to the hard palate and the maxillary sinus, a case that to our knowledge has not been reported before. Various malignant tumours that metastize to the maxilla are reviewed, and the therapeutic approach to follicular thyroid carcinoma metastasis to that area is also discussed. Follicular thyroid carcinoma should be included in the list of tumours that metastasize to the maxilla.

Brachytherapy↗
PubMed1998

Fibroepithelial polyps of the anus: a histologic, immunohistochemical, and ultrastructural study, including comparison with the normal anal subepithelial layer.

Fibroepithelial polyps of the anus (FEPA) are relatively common lesions that have attracted little attention. A series of 40 FEPA, together with sections from normal anal mucosa, were studied histologically, histochemically, immunohistochemically, and ultrastructurally. The polyps consisted of myxoid or collagenous stroma covered by squamous epithelium. Stromal cells with two or more nuclei were found in 30 polyps (80%). In five cases (12%) these cells showed atypical nuclear features. All the polyps harboring atypical cells were of large size. Mast cells were frequently present and sometimes intimately related to the stromal cells. Stromal cells stained positive for vimentin and negative for actin. Desmin was expressed in 30% of the cases. Electron microscopic examination confirmed the fibroblastic and myofibroblastic nature of the stromal cells. Examination of the subepithelial connective tissue from the normal anal mucosa showed bizarre multinucleated cells and mast cell infiltration. It is concluded that FEPA are benign lesions characterized by the presence of mononucleated and multinucleated, sometimes atypical stromal cells showing fibroblastic and myofibroblastic differentiation. The morphologic similarity between FEPA and normal anal mucosa supports the hypothesis that FEPA may represent a reactive hyperplasia of the subepithelial connective tissue of the anal mucosa. Mast cells, by means of their fibrogenic, fibrolytic, and angiogenic activities may play an important role in the pathogenesis of FEPA.

Adolescent↗
PubMed1998

Mucicarminophilic histiocytosis (benign signet-ring cells) and hyperplastic mesothelial cells: two mimics of metastatic carcinoma within a single lymph node.

We describe a unique case of simultaneous signet-ring histiocytes containing polyvinylpyrrolidone (mucicarminophilic histiocytosis) and hyperplastic mesothelial cells within a single supraclavicular lymph node. Both types of cells expanded the nodal sinuses and were initially suspected of being metastatic carcinoma. Histologic features suggested the correct diagnoses, which were confirmed by histochemical and immunohistochemical staining. It is important for pathologists to be aware of these phenomena, so as to avoid a misdiagnosis of metastatic carcinoma.

Adult↗
PubMed1997

Multiple antral ulcers in gastric sarcoid.

A 33-year-old woman suffered a week of severe epigastric pain and subsequent weight loss. On upper-gastrointestinal endoscopy several superficial ulcers were evident in the antral region. Mucosal biopsies from the ulcers showed epithelial cell granulomas. Even though no hilar lymphadenopathy was present on the chest radiograph and computed tomographic scan, the patient underwent bronchoscopy and transbronchial biopsy, which showed noncaseating epithelial cell granuloma, and bronchoalveolar lavage, which showed a lymphocytic pattern suggestive of sarcoidosis. Reports of gastric involvement in systemic sarcoidosis with no bilateral hilar lymphadenopathy are rare. We believe this is the first report of symptomatic gastric ulcers leading to endoscopic diagnosis of the underlying sarcoidosis.

Adult↗
PubMed1996

Calcified concretions in the anterior pituitary gland of the fetus and the newborn: a light and electron microscopic study.

Calcified concretions including typical laminated psammoma bodies can be detected on routine hematoxylin-eosin (H&E) examination of fetal and neonatal anterior pituitary glands. This finding has seldom been reported in the literature and, to the authors' knowledge, no ultrastructural examinations of fetal or neonatal pituitary calcifications have been reported to date. In this study, histological sections of anterior pituitary glands from 200 fetuses and infants ranging in age from 15 weeks of gestation to 1 year of life revealed calcified concretions in all the cases up to 1 month of life. They decreased in incidence postnatally and were not found after 6 months of age. Most were round to ovoid, basophilic or eosinophilic, often laminated, and measured between 5 and 30 microm in diameter. Immunohistochemical stains showed that the calcifications followed no particular pattern of distribution among the most prevalent pituitary cell types. Ultrastructural examination revealed small single or multiple intracellular calcified deposits, and larger, sometimes laminated, extracellular calcifications, suggesting an intracellular origin for the concretions with cell death occurring concomitant with their formation. This phenomenon, which to some extent resembles the formation of psammoma bodies in certain tumors, seems to represent a distinctive morphological type of developmental cell death. Apoptosis, a more common form of developmental cell death, was also found in some of the sections. Pathologists should be aware of the fact that calcified concretions represent a normal finding in the anterior pituitary gland of fetuses and young infants. Their mere presence in cases of fetal or perinatal demise with no other pertinent findings should not be attributed to intrauterine viral infections or ischemic-anoxic events.

Calcification, Physiologic↗
PubMed1996

Collagenous gastritis associated with lymphocytic colitis.

Collagenous sprue and collagenous colitis are two well-recognized idiopathic enteritides whose defining histologic attribute is fibrous thickening of the subepithelial basement membrane. Analogous changes in gastric mucosa seem to be quite rare. The term "collagenous gastritis" was recently applied for the first time to an isolated case of refractory gastritis in which distinctive subepithelial gastric fibrosis was noted. We report an additional case of this entity in a 35-year-old woman with refractory dyspepsia. In contrast to the earlier case of collagenous gastritis, our patient also had lymphocytic colitis, a type of colitis associated with watery diarrhea. Collagenous gastritis appears to be a distinct clinicopathologic entity, the histologic changes of which should be sought in patients with unexplained dyspepsia. Increased awareness of this condition and its possible clinical correlates may provide clues to its etiology and pathogenesis.

Adult↗