Round Nuclei (round + nucleus)

Distribution by Scientific Domains


Selected Abstracts


Fine-needle aspiration biopsy findings in sclerosing polycystic adenosis of the parotid gland

DIAGNOSTIC CYTOPATHOLOGY, Issue 7 2007
Demet Etit M.D.
Abstract Sclerosing polycystic adenosis (SPA) is a recently described, rare lesion of the salivary gland analogous to fibrocystic disease of the breast. Recognition of this benign entity is important since the differential diagnosis includes other more common benign and malignant salivary gland neoplasms, particularly mucoepidermoid carcinoma and tumors with cystic and oncocytic features. While the histomorphology of SPA is well documented, there is only one other cytologic description of SPA in the English-language literature. Here we describe the fine-needle aspiration biopsy findings in a case of SPA of the parotid gland in an 84-year-old woman. The aspirate was characterized by flat cohesive sheets of epithelial cells with moderate amounts of finely granular oncocytic cytoplasm and enlarged round nuclei with indistinct nucleoli. Some epithelial groups formed glandular structures with lumens, and the background contained small amounts of delicate mucoproteinaceous material. Occasional markedly vacuolated cells were present as well as many cells with apocrine change manifested by well-defined apical snouting. Familiarity with the cytomorphologic features of SPA, including its characteristic apocrine changes, is important for distinguishing it from other more clinically significant salivary gland lesions. Diagn. Cytopathol. 2007;35:444,447. © 2007 Wiley-Liss, Inc. [source]


Clear-cell adenocarcinoma of the female genital tract: Presence of Hyaline stroma and tigroid background in various types of cytologic specimens

DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2005
Surapan Khunamornpong M.D.
Abstract Hyaline basement membrane-like stromal material and tigroid background are distinctive cytologic features observed in Diff-Quik (DQ)- or Giemsa-stained smears of clear-cell adenocarcinoma (CCA) of the female genital tract. However, it is uncertain how often these features are present in different types of cytologic specimens, and which type of preparation is optimal for this diagnosis. We therefore reviewed the cytologic features of CCA in three types of specimens, including 15 scrape cytology specimens, 7 fine-needle aspiration (FNA) specimens, and 15 peritoneal cytology specimens, with emphasis on the features observed in DQ-stained smears. The cell morphology in scrape cytology specimens and FNA specimens was comparable, whereas in peritoneal cytology specimens, the cytoplasm was better preserved. Most tumor cells had fragile cytoplasm containing variable amounts of fine vacuoles, and round nuclei with distinct or prominent nucleoli. Hyaline stroma was present in 93% of scrape cytology specimens, 71% of FNA specimens, and 80% of peritoneal cytology specimens. Tigroid background was observed in 47% of scrape cytology specimens, 43% of FNA specimens, but in none of the peritoneal cytology specimens. Formation of a tigroid background may be prevented by the abundant fluid content in peritoneal cytology specimens. Hyaline stroma and tigroid background were uncommonly seen in scrape smears from other types of primary ovarian tumors, mainly juvenile granulosa cell tumor and yolk sac tumor. However, the additional presence of papillary structures allows CCA to be readily distinguished from these other tumors. We propose that scrape cytology offers the best approach for the intraoperative cytologic diagnosis of CCA. Diagn. Cytopathol. 2005;32:336,340.© 2005 Wiley-Liss, Inc. [source]


Carcinomas arising in multilocular thymic cysts of the neck: a clinicopathological study of three cases

HISTOPATHOLOGY, Issue 1 2004
C A Moran
Aims :,To report three cases of primary carcinoma of the neck arising in multilocular thymic cysts (MTC). Methods and results :,The patients were three men aged 47, 50 and 52 years who presented with a painless neck mass of several weeks' duration. The patients had no history of previous surgical procedures or of malignancy elsewhere. The tumours in all three patients were located on the right lateral side of the neck; all patients underwent complete surgical resection of the mass. Grossly, the tumours were cystic and measured between 20 and 30 mm in greatest diameter. Histologically, the tumours showed cyst walls lined by squamous epithelium. The cyst walls contained prominent germinal centres with lymphoid hyperplasia, cholesterol cleft granulomas, and scattered keratinized structures reminiscent of Hassall's corpuscles. In addition, a neoplastic cellular proliferation composed of round to oval cells arranged in sheets and originating from the lining of the cystic structures was present. The neoplastic cells showed moderate amounts of eosinophilic cytoplasm, round nuclei, and, in some areas, prominent nucleoli. Mitotic figures were easily found, and cellular pleomorphism was present in several areas. In two cases the tumours showed features of basaloid carcinoma of the thymus, while in one case the pattern was that of squamous cell carcinoma. Immunohistochemical studies for keratin showed a strong positive reaction in the tumour cells, while leucocyte common antigen strongly stained the lymphoid background. Follow-up information obtained in two patients showed them to be alive 6 months after initial diagnosis. One patient was lost to follow-up. Conclusion :,The cases described here represent an unusual variant of carcinoma arising in multilocular thymic cyst in the neck region. [source]


Glomus Coccygeum: Report of a Case

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005
A. Rahemtullah
The glomus coccygeum is a vestigial structure related to the canals of Sucquet-Hoyer, an arteriovenous anastomosis surrounded by glomus cells derived from modified smooth muscle and involved in thermoregulation. It is an incidental finding in specimens from the sacral area and may represent a diagnostic challenge to the unaware observer. We present a case of a glomus coccygeum, presenting as a 1.5 mm structure adjacent to a typical pilonidal cyst excised from a 7-month-old boy, that was the subject of a second opinion consultation. The lesion showed small to medium sized clusters of predominantly epithelioid cells with moderate amounts of clear to eosinophilic cytoplasm, intercellular borders and plump, round nuclei with fine chromatin. These cells were closely associated with small vascular channels and nerves. Immunohistochemistry revealed that the epithelioid cells expressed vimentin, muscle-specific actin, neuron-specific enolase, and S-100 protein, were weakly positive for smooth muscle actin, and negative for desmin, synaptophysin and chromogranin. The endothelial cells of the vascular channels were antibody CD31 positive. Recognition of the histological features of glomus coccygeum is important to avoid confusion with glomus tumor and neural or smooth muscle neoplasms in the sacral area. [source]


Pancreatic acinar cell carcinoma extending into the common bile and main pancreatic ducts

PATHOLOGY INTERNATIONAL, Issue 10 2006
Rin Yamaguchi
Acinar cell carcinoma (ACC) of the pancreas is relatively rare, accounting for only approximately 1% of all exocrine pancreatic tumors. A 69-year-old man was found to have a mass lesion measuring approximately 4 cm in diameter in the pancreatic head on ultrasound, abdominal dynamic CT, and percutaneous transhepatic cholangiography. Magnetic resonance cholangiopancreatography showed defect of the lower common bile duct (CBD) due to obstruction by the tumor cast. Histopathologically, the pancreatic head tumor invaded the main pancreatic duct (MPD) and CBD with extension into the CBD in a form of tumor cast. The tumor cells consisted of a solid proliferation with abundant eosinophilic cytoplasm and round nuclei in an acinar and trabecular fashion. A 55-year-old man with upper abdominal pain and nausea, had a cystic lesion approximately 3 cm in size in the pancreatic tail on CT. Histopathologically, the tumor was encapsulated by fibrous capsule and had extensive central necrosis with solid areas in the tumor periphery, and invaded with extension into the MPD in a form of tumor cast. The tumor cells resembled acinar cells in solid growths. Two resected cases of ACC with unusual tumor extension into the CBD and the MPD, respectively, are reported. [source]


Anal canal neuroendocrine carcinoma with Pagetoid extension

PATHOLOGY INTERNATIONAL, Issue 8 2004
Limei Guo
A case of anal canal neuroendocrine carcinoma with Pagetoid intraepithelial extension is presented. An 80-year-old man was admitted to hospital with a complaint of pain in the anorectal region. Clinical examination revealed a hard and fixed mass in the anal canal, and subsequent biopsy of the lesion showed it to be a carcinoma. The surgically resected specimen showed a solid tumor measuring 3.4 × 3.2 cm within the area from the surgical anal canal to the anatomical anal canal. Tumor cells proliferated predominantly with compact nests. Many tumor cells had a high nuclear-to-cytoplasmic ratio, dispersed chromatin, and conspicuous nucleoli. Additionally, neoplastic cells focally formed a glandular structure. Some polygonal neoplastic cells were small with round nuclei. A rosette-like arrangement was also focally observed. In addition, tumor cells exhibited Pagetoid extension into the overlying epithelium of the histological anal canal. Both the underlying original neoplastic cells and the Pagetoid spreading tumor cells showed cytoplasmic granules positive for Grimelius staining and immunopositivity for carcinoembryonic antigen, synaptophysin and cytokeratins 7 and 20. These findings are highly suggestive of neuroendocrine differentiation of adenocarcinoma cells. To the best of our knowledge, this is the first case of anal canal neuroendocrine carcinoma with Pagetoid extension into the overlying epithelium of the histological anal canal. [source]


,, T-cell large granular lymphocyte (LGL) leukemia with spontaneous remission

AMERICAN JOURNAL OF HEMATOLOGY, Issue 3 2004
Tsutomu Shichishima
Abstract T-cell large granular lymphocyte (LGL) leukemia is a clonal disorder with an indolent clinical course. In July 1995, a 46-year-old Japanese man was admitted to our hospital because his anemia had progressed. He had a white blood cell count of 3.9 × 109/L with 75% lymphocytes, which were intermediate to large and had almost round nuclei and azurophilic granules, and anemia with a red blood cell count (RBC) of 2.69 × 1012/L, hemoglobin (Hb) of 9.5 g/dL, and hematocrit (Hct) of 28.3%. Electron microscopic examination showed that most of the lymphocytes had a parallel tubular array and dense core granules in their cytoplasm. Flow cytometry and Southern blotting of the T-cell antigen receptor (TCR) genes using the peripheral blood species showed monoclonal proliferation of LGLs with a CD3+, TCR,,+, CD4,, CD8,, CD16+, CD56,, CD57,, HLA-DR+ phenotype, and a TCR , gene rearrangement, respectively, suggesting that the patient was diagnosed as having ,, T-cell LGL leukemia. He had no symptoms, organomegaly, or skin lesions. About 1.5 years after diagnosis, the anemia gradually improved with disappearance and appearance of a rearranged band in the TCR-, gene and TCR-, gene, respectively. About 7 years after diagnosis, the anemia improved completely with a RBC of 5.01 × 1012/L, Hb of 14.8 g/dL, and Hct of 44.3%, and he was in complete remission without TCR-, and -, gene rearrangements. He had received no therapy. This is the first report of spontaneous remission of ,, T-cell LGL leukemia. Am. J. Hematol. 75:168,172, 2004. © 2004 Wiley-Liss, Inc. [source]


Human herpes virus 8-unrelated primary effusion lymphoma-like lymphoma: report of a rare case and review of the literature

APMIS, Issue 3 2009
CAFER ADIGUZEL
Primary effusion lymphoma (PEL) is a very rare type of lymphoma usually confined to the body cavities predominantly in immunosupressed patients infected with human herpes virus 8 (HHV-8). The new term for HHV-8 independent PEL is HHV8-unrelated PEL-like lymphoma. We describe an 89-year-old human immunodeficiency virus (HIV)-negative male patient with HHV8-unrelated PEL-like lymphoma in the pleura. No hepatosplenomegaly or lymphadenopathy was detected. Chest radiography and computed tomography revealed right pleural effusion, but no evidence of tumor mass or lymph node enlargement. Cytological analysis of the pleural effusion revealed a high-grade lymphoma with round nuclei, prominent nucleoli and abundant cytoplasm with immunophenotypes positive for CD45, CD30, CD38, CD7 and CD71. Because of the advanced age, no chemotherapy was given. Effusion resolved spontaneously. One year after the diagnosis, a new pleural effusion developed at the left side. Following thoracentesis and pleurodesis, the patient remained in complete remission for 40 months. To date, 30 cases of HHV8-unrelated PEL-like lymphoma/HIV negative have been reported in the literature. The outcome of the HHV8-unrelated PEL-like lymphoma patients who were HIV negative seems to be better than HIV- and HHV-8-positive PEL. [source]


Acute viral lymphadenitis mimicking low-grade peripheral T-cell lymphoma A clinicopathological study of nine cases,

APMIS, Issue 6 2001
Masaru Kojima
Acute viral lymphadenitis, especially infectious mononucleosis (IM), often shows the presence of Reed-Sternberg-like cells, resulting in confusion with Hodgkin's disease. However, acute viral lymphadenitis requiring differential diagnosis from non-Hodgkin's lymphoma is not widely recognized. We describe the clinicopathological and immunohistochemical features of lymph node lesions from nine such patients which pose serious problems of differential diagnosis from low-grade peripheral T-cell lymphoma. There were three males and six females with ages ranging from 21 to 44 years (median 25 years). All patients had "B" symptoms and multicentric lymphadenopathy. The clinical course was also self-limiting. Each lymph node specimen showed an obvious expansion of an interfollicular area by pleomorphic and polymorphous infiltration with an increased number of arborizing postcapillary venules. The infiltrate was composed of variable numbers of small and medium-sized lymphocytes, immunoblasts, plasma cells in various stage of maturation and occasional granulocytes. The small lymphocytes usually had regular round nuclei, whereas the medium-sized lymphocytes occasionally showed nuclear pleomorphism. Hyperreactivity of B-lymphocytes, including hyperplastic germinal centers and/or foci of monocytoid B-cells, was seen in parts of the lesion. The majority of the interfollicular T-lymphocytes, including T-immunoblasts, expressed CD8 antigen. Various numbers of TIA-1-positive small and medium-sized T-cells were observed in the paracortical area. Despite these findings, the overall histological picture of this series posed serious difficulties when differentially diagnosing this condition from low-grade peripheral T-cell lymphomas such as angioimmunoblastic T-cell (AILD) and T-zone types, indicating that viral lymphadenitis occasionally presents with histological features of AILD and T-zone lymphomas. To avoid overdiagnosis and overtreatment, we emphasize the need to pay careful attention to the clinical and laboratory findings as well as the morphological features. [source]


Non-contiguous recurrence or secondary choroidal melanoma following plaque radiotherapy

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 7 2007
Mauricio Maia MD
Abstract Non-contiguous local recurrence of posterior uveal melanoma occurs rarely after plaque therapy. A 50-year-old white first presented with choroidal melanoma. He underwent therapy with episcleral iodine-125 radioactive plaque therapy. Nine years later fundus evaluation revealed a new pigmented lesion in the inferotemporal equatorial area. Patient was considered to have a non-contiguous recurrent melanoma and the eye was enucleated. Histologic microscopic examination disclosed a 3 × 1.8 mm densely pigmented tumour internal to the choroid at the equator. The tumour was composed of large round cells with round nuclei, prominent nucleoli, abundant cytoplasm and spindle-shaped cells with spindle-shaped nuclei and prominent nucleoli. The tumour extended through the retina. The superior nasal area of plaque therapy had extensive chorioretinal atrophy with loss of retinal pigment epithelium, thinning of the retina and thinning and depigmentation of the choroids. Within this area of atrophy, there was a pigmented lesion composed by densely packed, spindle-shaped cells with spindle-shaped nuclei. Our patient illustrated non-contiguous recurrence of choroidal melanoma, such finding raises concerns about physiopathology and treatment of choroidal melanoma. [source]


Formation of the Fertilization Pore during Oogenesis of the Fern Ceratopteris thalictroides

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 6 2010
Jian-Guo Cao
The development of the fertilization pore during oogenesis of the fern Ceratopteris thalictroides was followed using transmission electron microscopy. The newly formed egg is appressed closely to the adjacent cells. There are well-developed plasmodesmata between the egg and the ventral canal cell, but none between the egg and the jacket cells of the archegonium. During maturation, a separation cavity is formed around the egg. However, a pore region persistently connects the egg and the ventral canal cell. The extra egg membrane is formed by deposition of sheets of endoplasmic reticulum (ER), but no ER is deposited on the inner surface of the pore region. Thus, a fertilization pore, covered by a layer of plasmalemma, is formed. The ventral canal cell undoubtedly participates the formation of the fertilization pore, probably by absorbing the sheets of ER beneath the pore region. The functional significance of the ventral canal cell in formation of the fertilization pore is discussed. The features of the mature egg include that abundant concentric membranes and osmiophilic vesicles occur in the cytoplasm of the mature egg. The initial, round nucleus of the egg eventually becomes cup-shaped. This investigation gives some new insights about the cells participating oogenesis in ferns. [source]