Biomedical subjects

Nobuhide Masawa

Publications and source records attributed to Nobuhide Masawa.

47 records · Page 3Linked to original sources

PubMed2003

Sclerosing variant of follicular lymphoma arising from submandibular glands and resembling "Küttner tumor": a report of 3 patients.

We present 3 patients with a sclerosing variant of follicular lymphoma that arose from the submandibular gland and resembled "Küttner tumor." All 3 patients developed a painless unilateral tumor in the submandibular region. Histologically, all 3 lesions were categorized as follicular lymphoma grade 2. The neoplastic follicles were found to be separated by thick connective tissue, and periductal chronic inflammation with periductal fibrosis and duct ectasia was found in the residual atrophic gland. Immunohistochemistry revealed that all of the lesions contained a monoclonal tumor cell population. The immunophenotyopes of the lymphoma cells were CD 10+, CD 20+, CD 79a+, BCL-6+, CD 3-, CD 5-, CD 21-, CD 23-, CD 43-, CD 45RO-, BCL-2-, and Cyclin D1-. Two of the 3 patients exhibited clonal bands for the IgH gene by polymerase chain reaction assay. "Küttner tumor," which is a common fibrosing, chronic inflammatory lesion of the submandibular gland, is sometimes diagnosed as a malignant tumor. This study indicates that this sclerosing variant of follicular lymphoma should be added to the list of different diagnoses for "Küttner tumor."

Aged↗

PubMed2002

Follicular hyperplasia presenting with a marginal zone pattern in a reactive lymph node lesion.

Histologically, the marginal zone pattern of the lymph node is characterized by lymphoid follicles with three distinct layers. The inner layer is composed of follicular center zones, the middle layer of darkly stained mantle zones, and the outer layer of marginal zones. However, the marginal zone pattern is rarely seen in reactive lymph nodes except for mesenteric lymph nodes. We describe the clinicopathologic, immunohistochemical and genotypic findings of six cases of reactive follicular hyperplasia exhibiting the marginal zone pattern. The patients comprised three males and three females (age range 24 to 63 years; medium 56 years). Follow-up data were obtained from five patients. None of them developed malignant lymphomas during the follow-up period of from 5 to 204 months (median 68 months). Histologically, the lesion was characterized by numerous lymphoid follicles and partial distortion of lymph node structure. Varying degrees of progressive transformation of the germinal center (PTGC) were noted in the four cases. The marginal zone pattern was observed in some or most of the lymphoid follicles including PTGC. The marginal zone B cells were small to medium-sized lymphocytes with round or slightly indented nuclei and a broad rim of pale cytoplasm. Some of them had a monocytoid appearance. They were CD20+, CD79a+, sIgM+/-, sIgD-, CD5-, CD10-, CD21-, CD23-, CD43-, CD45RO-, Bcl-6-, cyclin D1-, EMA- and p53-. A portion of them were Bcl-2 positive. Occasional large lymphoid cells with round or indented nuclei and moderate amounts of cytoplasm were observed in the marginal zone in four cases. These large lymphoid cells were usually CD20 positive, but Bcl-6 negative. A small number of them contained polytypic intracytoplasmic immunoglobulins. The polytypic nature of B lymphocytes was demonstrated by immunohistochemistry and polymerase chain reaction. Recognition of unusual marginal zone hyperplasia in reactive lymph node lesions is important to avoid confusion with nodal involvement in various low-grade B cell lymphomas presenting a marginal zone distribution pattern.

Adult↗

PubMed2002

Nodal marginal zone B-cell lymphoma resembling plasmacytoma arising from a plasma cell variant of localized Castleman's disease: a case report.

Nodal marginal zone B-cell lymphoma (NMZBL) occasionally represents prominent plasma cell differentiation. Recently, primary lymph node plasmacytoma has been suggested to represent an extremely plasmacytic differentiation of NMZBL. We here report a case of NMZBL showing histological features resembling plasmacytoma arising from a plasma cell variant of localized Castleman's disease (PCLCD). The patient was a 69-year-old Japanese female with a 20-year history of a right inguinal mass. Histologically, a prominent proliferation of plasma cells occupied the interfollicular area of the central portion of the lymph node, whereas centrocyte-like (CCL) cells were the main cellular component in the peripheral portion of the lymph node. Although most of the plasma cells were mature 'Marshalko-type', occasional atypical forms with enlarged nuclei were also present. The majority of the lymphoid follicles had atrophic or regressive germinal centers. A few lymphoid follicles were colonized by CCL cells. Immunohistochemistry study revealed that both plasma cells and some CCL cells had a monotypic intracytoplasmic lambda light chain. When monoclonal plasma cell infiltration is observed in PCLCD, the light chains are mostly restricted to the lambda chain. This case suggests that some plasma cell-containing tumors arising from PCLCD may represent a variant of NMZBL.

Aged↗

PubMed2002

Primary marginal zone B-cell lymphoma of the lymph node resembling plasmacytoma arising from a plasma cell variant of Castleman's disease. A clinicopathological and immunohistochemical study of seven patients.

Nodal marginal zone B-cell lymphomas (NMZBL) occasionally represent prominent plasma cell differentiation. Recently, we presented a patient with NMZBL who exhibited histological features that resembled plasmacytoma arising from a localized plasma cell variant of Castleman's disease. To further clarify the clinicopathological, immunohistochemical, and genotypical findings, we studied seven such patients. Clinically, these patients were characterized by localized disease and an indolent clinical course with a slowly growing bulky mass in the affected lymph node. Only one patient exhibited paraproteinemia. Histologically, the lesions were characterized by numerous evenly distributed germinal centers in extensive sheets of plasma cells. Various numbers of centrocyte-like (CCL) cells arranged in a marginal zone distribution pattern occupied the peripheral region of the lymph node. The majority of the lymphoid follicles had atrophic or regressive germinal centers. A few lymphoid follicles were colonized by CCL cells. Immunohistochemistry showed that all of the lesions contained a monoclonal plasma cell population. In three tumors, a number of the CCL cells had a similar light chain restriction pattern to that observed in plasma cells. Two of the four patients evaluated exhibited clonal bands for the IgH gene by polymerase chain reaction assay. Moreover, the presence of surface IgM+, IgD- and CD27+ CCL- cells suggests that these tumors are derived from memory B-lymphocytes.

Adult↗

PubMed2002

A case of segmental mediolytic arteriopathy involving both intracranial and intraabdominal arteries.

Segmental mediolytic arteriopathy (SMA) is an uncommon nonatherosclerotic and nonvasculitic arteriopathy. This disease is characterized by lytic degeneration of the arterial media, intramural dissection and thrombosed or ruptured aneurysm. SMA mainly involves the intraabdominal arterial system, resulting in intraabdominal and retroperitoneal hemorrhage. However, only a few cases of SMA with involvement of intracranial arteries have been reported. Here, we present a case of SMA developing subarachnoid hemorrhage due to dissection of the internal carotid and vertebral arteries. This patient was a 48-year-old male who died 13 days after admission for sudden loss of consciousness. Computed tomography showed subarachnoid hemorrhage. At autopsy, the affected vessels included the right vertebral, left internal carotid, superior mesenteric, bilateral renal and left external iliac arteries. Histopathologically, the arteries showed segmental lytic degeneration and disappearance of medial smooth muscle cells, medial dissection and formation of pseudo-aneurysms, the wall of which consisted of a thin membrane of the adventitia. These histopathological features mimicked an entire wall dissection type of intracranial dissecting aneurysm, which exclusively affects the vertebro-basilar system. Thus, SMA should be considered a possible underlying disease in patients with spontaneous dissection of intracranial arteries.

Aneurysm, False↗

PubMed2002

Primary pulmonary low-grade marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type with prominent hyalinosis. A case report.

We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sjögren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT.

Aged↗

PubMed2002

Cellular composition of subacute thyroiditis. an immunohistochemical study of six cases.

To clarify the cellular composition of subacute thyroiditis, histologic and immunohistochemical studies were performed. Histologically, the lesion presented a patchy distribution of non-caseous granulomas comprising colloid, small lymphocytes, neutrophils, macrophages with or without epithelioid features, and multinucleated giant cells of foreign body type. In addition, numerous plasmacytoid monocytes were closely associated with the granulomas. The giant cells were CD68+, thyroglobulin- and cytokeratin-. Usually, small lymphocytes in the granulomas are CD3+, CD8+, CD45RO+ cytotoxic T-cells. In the non-granulomatous lesion, the follicles were often infiltrated by CD8+ T-lymphocytes, plasmacytoid monocytes and histiocytes, resulting in disrupted basement membrane and rupture of the follicles. Lymphoid follicles with or without active germinal centers were not observed. Moreover, no residual follicular dendritic cell networks were detected by CD23 and CAN.42 immunostains. In the interfollicular area, scattered plasma cells were observed among infiltrating cells. Neither human herpes virus 8 nor EBER-positive cells were detected in the six patients. The findings of our study suggest that cellular immune response may play an important role in the pathogenesis of subacute thyroiditis.

Aged↗

PubMed2002

Centroblastic and centroblastic/centrocytic lymphoma associated with a prominent epithelioid granulomatous response: a clinicopathologic study of 50 cases.

A minority of centroblastic and centroblastic/centrocytic cell lymphomas are accompanied by a prominent epithelioid cell response and were suggested to be a distinct variant of B-cell lymphoma of germinal center cell origin. To confirm the clinicopathologic significance of these mainly large B-cell lymphomas with an epithelioid cell response (LBCL-ER), we reviewed 50 patients with LBCL-ER and compared the results with those of 167 other diffuse large B-cell lymphomas (DLBCL) and 94 follicular lymphomas (FL) without epithelioid response. The patients with LBCL-ER showed a higher age distribution (median 71, P =.03), a female predominance (M:F = 18:32, P =.001) and less frequent involvement of extranodal sites >1 (P =.004) compared with those with DLBCL, and presented with a bulky mass of the affected lymph nodes in 54% of cases. They were also older (P =.0006) and more associated with the aggressive clinical factors such as serum LDH level and International Prognostic Index score than those with FL. Histologically, nine cases (18%) partially showed a follicular growth pattern, and the others (82%) were occupied by a diffuse growth pattern. The epithelioid cells were accumulated in large demarcated masses, partially imparting a lymphoepithelioid (Lennert) lymphoma-like appearance to some portions of the lesions in every case. Immunohistochemically, LBCR-ER was positive for CD20 in every case, CD10 in 43% of the cases, and BCL-2 in 56%. None of the tumor cells in the 40 cases tested expressed CD5 antigen. Immunostaining also often highlighted the remnants of the follicular dendritic cell network. The BCL-2 gene rearrangement was detected in only 19% of the cases examined. The survival curve of the cases of LBCL-ER was almost identical with that of DLBCL and was significantly inferior to that of FL. The centroblastic and centroblastic/centrocytic lymphoma with an epithelioid cell response may be regarded as the morphologic variant of DLBCL preferentially arising in the aged population and reflecting the disease progression of FL.

Adult↗

PubMed2002

Lymph node lesion in adult-onset Still's disease resembling peripheral T-cell lymphoma: a report of three cases.

Adult-onset Still's disease (AOSD) is known to be a cause of fever of unknown origin. We describe the clinicopathologic, immunohistologic, and genotypic features of 3 patients with lymph node lesions from AOSD, which posed a serious diagnostic difficulty from peripheral T-cell lymphomas. The patients were 22-, 26-, and 63-year-old Japanese women. At the onset of disease, all patients had multicentric lymphadenopathy in association with clinical and laboratory findings suggestive of a malignant lymphoma. None of the patients developed malignant lymphomas during the follow-up period. Histologically, the lesions were characterized by paracortical hyperplasia with prominent vascular proliferation. In the paracortical area, there was a mixed infiltrate including small-to-medium-sized lymphocytes, variable numbers of eosinophils, plasma cells, and B immunoblasts. Polymerase chain reaction analysis demonstrated that neither clonal rearrangement of the T-cell receptor gamma-chain gene nor immunoglobulin heavy-chain rearrangement was detected in any patient. Although AOSD appears to be a rare systemic inflammatory disorder, the lymph node lesion should be added to the differential consideration of benign lymph node lesions simulating node-based peripheral T-cell lymphoma.

Adult↗

PubMed2002

Lymph node infarction associated with infectious mononucleosis: report of a case resembling lymph node infarction associated with malignant lymphoma.

A completely infarcted lymph node should alert the pathologist to the high possibility of malignant lymphoma. The lymph node lesion of infectious mononucleosis (IM) shows marked histologic diversity and occasionally may be confused with malignant lymphoma. We report a rare case of IM showing extensive lymph node infarction whose lymph node lesion was similar to lymph node infarction associated with malignant lymphoma. This case describes a 32-year-old Japanese man who had signs and symptoms consistent with IM, which he was later proven serologically to have, but whose cervical lymph node showed extensive lymph node infarction with a thin area of granulation tissue beneath the capsule. The infarcted tissue contained numerous eosinophilic ghosts of large lymphoid cells. The thin granulation tissue was composed of numerous small lymphocytes, plasma cells, and histiocytes, in addition to large lymphoid cells including immunoblasts and granulocytes. CD20, CD3, and CD45RO immunostains revealed the mixed B- and T-cell nature of the ghosts of large lymphoid cells in the infarcted tissue as well as viable large cells in the granulation tissue. The patient was free from disease after 50 months' follow-up.

Adult↗

PubMedDate not supplied

Five percent, 7.5% or 10% hypertonic saline prevents delayed neuronal death in gerbils.

PURPOSE: To clarify the appropriate concentration and dose of hypertonic saline solution (HSS) for preventing delayed neuronal death in the hippocampal CA1 subfield after transient forebrain ischemia in gerbils. METHODS: Thirty gerbils were randomly assigned to five groups: physiological saline solution (PSS) group, ischemia/reperfusion treated with PSS 2 mL x kg(-1); 5% HSS group, treated with 5% HSS 2 mL x kg(-1); 7.5% HSS group, treated with 7.5% HSS 2 mL x kg(-1); 10% HSS group, treated with 10% HSS 2 mL x kg(-1); 20% HSS group, treated with 20% HSS 2 mL x kg(-1). Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes. Five days later, histopathological changes in the hippocampal area were examined, and the degenerative ratio of the pyramidal cells were measured according to the following formula: (number of degenerative pyramidal cells/total number of pyramidal cells per 1 mm of hippocampal CA1 subfield) x 100. RESULTS: In PSS and 20% groups, neuronal cell damage was observed five days after ischemia. In the other three groups, these changes were not observed. The degenerative ratios of pyramidal cells were as follows; PSS group: 91.6 +/- 5.6%, 5% HSS group: 7.2 +/- 1.6%, 7.5% group: 8.3 +/- 1.4%, 10% HSS group: 6.2 +/- 1.1%, 20% HSS group: 85.8 +/- 8.7% (P < 0.05; PSS and 20% HSS vs three other groups). CONCLUSION: This study demonstrates that 5, 7.5 or 10% HSS 2 mL x kg(-1) may prevent delayed neuronal death in the hippocampal CA1 subfield after cerebral ischemia/reperfusion in gerbils.

Animals↗