1/28. An evaluation of antigen retrieval procedures for immunoelectron microscopic classification of amyloid deposits.The advantages of using immunoelectron microscopy in amyloid research and surgical pathology for the classification of amyloid deposits are well documented. The aim of this study was to improve single-labeling postembedding immunostaining by testing different antigen retrieval (AR) techniques. Etching and AR procedures were applied to sections from aldehyde-fixed and Epon-embedded autopsy specimens of patients who had suffered from generalized AA amyloidosis, systemic senile ATTR amyloidosis, or generalized kappa-light chain amyloidosis. The procedures used were no AR, H(2)O(2), saturated aqueous sodium metaperiodate (mPJ), heating in deionized water (dH(2)O), heating in sodium citrate buffer (SCB), heating in EDTA (each 91C, 30 min), and combinations of etching and heating. Little effect was evident after treatment with H(2)O(2), mPJ, and heating in dH(2)O, but the signal density markedly increased after heating in 1 mM EDTA. heating in SCB affected immunolabeling with anti-transthyretin and anti-kappa-light chain, whereas no effect was achieved for immunolabeling with anti-AA amyloid. We concluded that AR may significantly improve immunostaining of specimens that have undergone conventional fixation and embedding procedures for electron microscopy. The effect of AR on the detection of amyloid fibril proteins was probably mediated in part through chelation or binding of metal ions by the AR medium. (J Histochem Cytochem 47:1385-1394, 1999)- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/28. Extramedullary manifestation of multiple myeloma (systemic plasmacytoma) that simulates hemangioma.We describe 2 cases of a unique type of extramedullary manifestation of multiple myeloma (systemic plasmacytoma) that presented as subcutaneous nodules and mediastinal mass, respectively. Both lesions had a similar morphologic appearance, with dilated vascular-like lumina that was separated by thin fibrovascular septa, filled with erythrocytes, and lined by mature and immature plasma cells and plasmacytoid cells. The plasma and plasmacytoid lining cells showed kappa light chain restriction in both cases, consistent with a B-cell monoclonal process. The lining cells were also focally positive for epithelial membrane antigen but were negative for endothelial cell markers. Abundant delicate capillaries were seen in the septa that separated the vascular lumina, mimicking a vascular tumor. Furthermore, we believe that our cases are different from the previously described blood lakes in a plasmacytoma by the presence of well-formed fibrovascular septa that separated the vascular-like spaces. Neoangiogenesis propagated by myeloma cells may contribute to this unusual morphologic manifestation of extramedullary manifestation of multiple myeloma.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
3/28. Extramedullary plasmacytoma of the orbit.PURPOSE: To report a case of extramedullary plasmacytoma of the orbit. methods: A 71-year-old patient presented with diplopia eyelid fullness and limitation of ocular motility in the left eye. visual acuity was counting fingers, intraocular pressure 34 mmHg and fundus eye examination showed choroidal folds in the involved eye. RESULTS: CT scan showed a mass filling the superior and external left orbit without bone destruction. A biopsy was performed revealing that the tumour was composed of plasmacytoid cells positive with immunohistochemical stains for Kappa light chains and epithelial membrane antigen. Systemic work up was negative. The diagnosis of extramedullary orbital plasmacytoma was made. The patient was treated with external beam radiotherapy (40 Gy) and has remained disease free for four years (49 months). CONCLUSION: Extramedullary plasmacytomas of the orbit are extremely rare tumours. Accurate and early diagnosis is essential for the therapeutic approach. Extensive medical work up to rule out multiple myeloma or other malignant lymphoproliferative conditions involving the orbit is needed when the diagnosis of orbital extramedullary plasmacytoma is suspected because treatment and prognosis are very different.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
4/28. plasmacytoma with aberrant expression of myeloid markers, T-cell markers, and cytokeratin.Plasmacytomas are localized neoplastic proliferations of monoclonal plasma cells. When multifocal, the process is referred to as multiple myeloma. These lesions exhibit a pattern of antigen expression and cytomorphology that usually leads to a ready diagnosis. However, potentially troublesome variations in immunophenotype occur. We describe a case of a plasmacytoma from a patient who presented with sudden onset of pain and a lytic lesion of the left proximal humerus. hematoxylin and eosin-stained sections showed a lymphoproliferative lesion composed of large lymphoid cells, some with plasmacytoid and immunoblastic features. The lesion also showed significant mitotic activity. Immunohistochemical staining was positive for CD45 (LCA), CD56 (N-CAM), CD43 (MT1), and cytokeratin CAM5.2. There was also clonal staining for lambda light chains. In addition, flow cytometric analysis showed positivity for myeloid markers such as CD13, CD33, CD38, and CD138. Significant negative markers include CD20 (L26), CD45RO (UCHL-1), and CD79alpha. The unusual phenotypic features of this plasmacytoma illustrate potential diagnostic pitfalls. It is important to fully study such lesions to correctly classify them, because this has significant impact on prognosis and management.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
5/28. A case of extramedullary plasmacytoma of the larynx.An 84-year-old male with a complaint of hoarseness was examined. A mass lesion was recognized in the false vocal fold. The tumor was excised and found to consist of atypical plasmacytes. Immunopathological examination revealed that leukocyte common antigen (CD45), UCHLI (CD45RO), CD3 and L26 (CD20) were negative and that CD79 and Vs38C were positive. Neither uric Bence-Jones protein nor serum M-protein were observed. No other bony abnormalities were recognized on X-ray examinations including both bone and Ga scintigraphy. No atypical plasmacyte infiltration was observed in bone marrow. Our final diagnosis was extramedullary plasmacytoma of the larynx. radiotherapy was performed following surgery. The tumor did not progress to multiple myeloma and no recurrence has been observed after 2 years.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
6/28. Primary extramedullary plasmacytoma of the esophagus.An uncommon manifestation of plasma cell neoplasia occurs outside the bone marrow and is designated "extramedullary plasmacytoma." These are usually encountered in mucosal sites of the head and neck region. The gastrointestinal tract may be secondarily involved in multiple myeloma or be the site of primary extramedullary plasmacytomas (PEMPs). The esophagus is the least common site of gastrointestinal PEMP. A 58-year-old man presented with dysphagia for solids over a period of 2 months. Otherwise, he was well and systemic examination did not reveal anything of note. After a nondiagnostic biopsy, the patient was subjected to esophago-gastrectomy. Gross examination of the esophagus revealed a large polypoid tumor. Histologically, it was composed of mature plasma cells, plasmablasts (some of which appeared anaplastic), and a minor admixture of lymphoid cells. Focally, the infiltrate permeated the squamous epithelium simulating lymphoepithelial lesions. The neoplastic cells were positive for epithelial membrane antigen, CD79a, IgG, and kappa, while the lymphoid cells were predominantly B cells. The patient did not have a monoclonal gammopathy. Skeletal x-rays and bone trephine examination were both normal. PEMP is biologically and prognostically different to other plasma cell neoplasms. Although rare, esophageal PEMP should be considered in the differential diagnosis of so-called undifferentiated malignant tumors of the esophagus.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
7/28. Primary splenic presentation of plasma cell dyscrasia: report of two cases.Primary splenic presentation of plasma cell tumors is extremely rare. Recently we observed two female patients with primary (initially solitary) plasmacytoma of the spleen. While the pathoanatomical diagnosis of plasmacytoma could be established easily, the clinical picture in both cases was puzzling and allowed no definitive diagnosis to be made. One of the patients exhibited a long-standing monoclonal gammopathy. Repeated bone marrow examinations in both patients revealed slight increase in plasma cells (between 5 and 10% of all nucleated cells), but no infiltrates of multiple myeloma. The leading clinical feature in both cases was pronounced splenomegaly (780 g and 1600 g). Histologically both spleens exhibited marked infiltration by pleomorphic plasma cells, with monotypic expression of IgG kappa in one case and of the light chain lambda in the other. A broad panel of monoclonal antibodies detecting various hemopoietic and nonhemopoietic antigens was used to determine the immunophenotype of the neoplastic plasma cells, but in both cases they reacted only with a minority of the antibodies applied. The bone marrow in both cases remained free of tumorous infiltrates, but the disease progressed a few months after splenectomy with infiltration of the liver in one case and of lymph nodes in the other. To summarize, these two cases are definitely not multiple myelomas but could represent a distinct entity among the plasma cell dyscrasias for which the preliminary term "disseminated plasmacytoma with primary splenic presentation" is proposed.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
8/28. Epstein-Barr virus-induced transformation of cutaneous plasmacytoma into CD30 diffuse large B-cell lymphoma.A unique, previously unreported case of transformation of cutaneous plasmacytoma into CD30 large B-cell lymphoma is described. Both neoplastic components were immunophenotypically distinct. The plasma cells were CD20-, CD30-, CD43 , CD45 , lambda ; the blasts were CD20 , CD30 , CD43-, and CD45-. The large B-cell lymphoma has gradually become a predominant component of the neoplastic nodules. While plasma cells and blasts were both positive for Epstein-Barr virus-encoded nuclear RNAs (EBER-1), the EBV-latent membrane antigen 1 (EBV-LMP1) was expressed only in the minority of the blasts and not in the plasma cells. The neoplastic process has remained confined to the skin for more than six years since its development.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
9/28. Extramedullary plasmacytoma of the thyroid, associated with follicular colonization and stromal deposition of polytypic immunoglobulins and major histocompatibility antigens. Possible categorization in MALT lymphoma.A 78-year-old woman complaining of a neck mass underwent right hemithyroidectomy. The 7 x 6 cm thyroid tumor consisted predominantly of mildly atypical, epithelial membrane antigen-positive plasma cells and scattered lymphoid follicles. Features of follicular colonization (plasma cell infiltration into germinal centers) were noted. Numerous CD45RO-positive reactive T cells and a smaller number of CD20-positive blast-like B cells were also distributed among the plasma cell infiltrate. IgG, kappa-type monoclonality with J-chain reactivity was identified in the plasma cells, including those in the lymphoid follicles. The association of pre-existing lymphocytic thyroiditis was confirmed histologically in the non-tumorous thyroid tissue. The tumor exhibited deposition of reticulin fiber-rich, amorphous eosinophilic substances, provoking pronounced foreign body reactions. The deposit, polytypically immunoreactive for immunoglobulin gamma-, mu-, kappa- and lambda-chains, beta 2-microglobulin and HLA-DR, was scarcely reactive upon amyloid staining, and consisted ultrastructurally of electron-dense, non-fibrillar material and entrapped collagen fibers. multiple myeloma was ruled out by laboratory, histologic and clinical examinations. The possible categorization of this extramedullary plasmacytoma of the thyroid within low-grade B cell lymphoma of the mucosa-associated lymphoid tissue (MALT) is discussed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
10/28. Primary cutaneous plasmacytoma after rejection of a transplanted kidney: case report and review of the literature.Immunosuppressed organ allograft recipients are at risk of developing lymphomas and lymphoproliferative disorders as a consequence of immunosuppressive therapy and long-term antigenic stimulation from both the graft and possible viral infections. No more than 4% of the malignant tumors detected in organ recipients are plasmacytomas. Primary cutaneous plasmacytoma is a rare type of cutaneous B-cell lymphoma arising primarily in the skin. It is derived from clonally expanded plasma cells with various degrees of maturation and atypia. We report the occurrence of a solitary cutaneous plasmacytoma in a 56-year-old male patient undergoing hemodialysis after rejection of a grafted kidney. The diagnosis was made a few months after the kidney had been surgically removed. A thorough examination showed no evidence of systemic disease. skin lesions were successfully treated with local radiotherapy. After 2 years of follow-up there were no local or systemic recurrences.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
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