Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0268596 (EMA)
 2,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe the clinical course of a 20-year-old man who suffered generalized convulsive seizures with postictal aphasia and hemiparesis of the right side. Computed tomography (CT) displayed a left postcentral lesion with prominent perifocal edema and only a little contrast medium enhancement. The completely removed tumor proved to be a primary cerebral non-Hodgkin lymphoma consisting of T-cells. Only ten days after the operation the patient once more presented a clinical deterioration. A nuclear magnetic resonance imaging (MRI) displayed an annular structure in the area previously operated upon, suspected to be an abscess. The second operation disclosed a large recurrence of the primary T-cell lymphoma extending diffusely into the white matter. On account of the rapid recurrence, a whole brain irradiation was started twelve days after the second operation. Four cycles of chemotherapy followed. Immunohistochemical studies of the anaplastic large lymphoma cells showed staining with the pan T-cell markers (UCHL1, CD3) and with the CD30 (Ki-1) antibody. The B-cell markers (L26, LN1) were negative. The EMA (epithelial membrane antigen) was only partially expressed. Further investigation excluded the presence of systemic lymphoma manifestation. 24 months after the last operation the patient remained free of symptoms. The last MRI displayed no evidence for the recurrence of a lymphoma. In reference to this unusual clinical course the few previously reported cases of the extremely rare primary cerebral T-cell lymphoma are reviewed.
 ...
PMID:Primary cerebral anaplastic T-cell-lymphoma (type Ki-1): review and case report. 131 14

Both immunophenotypic overlaps between Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL), and evolution of one into the other have been reported. However, the underlying assumption that the antigenic expression of Reed-Sternberg (RS) cells is consistent in the same patient has not been evaluated. Such an evaluation was undertaken by immunophenotyping paraffin-embedded lymphoid tissue biopsies with HD from 56 patients in whom multiple specimens were obtained, either simultaneously from different sites or at different times. The panel of antibodies we used included: CD3 polyclonal antiserum, DAKO-M1 (CD15), L26 (CD20), BerH2 (CD30), MT1 (CD43), DAKO-LCA (CD45RB), UCHL1 (CD45R0), LN2 (CD74), and DAKO-EMA. The phenotype of RS cells was identical in simultaneous biopsies in only 11 of 39 patients (28%) and remained constant in consecutive biopsies in only 4 of 21 patients (19%). Major differences (relative to cell lineage specific antigens) were observed in 10 of 39 patients with simultaneous biopsies and in 10 of 21 patients over time; they mainly involved expression of T-cell antigens. Minor differences (relative to any other antigen) were observed in 22 of 39 patients with simultaneous biopsies and in 15 of 21 patients over time; these mainly involved CD15 or CD74. This striking variability of the immunophenotype of RS cells in the same patient may be due to aberrant marker expression, as a result of the neoplastic state, and/or to modulation of antigenic expression in relation to the host environment. This inconsistency suggests caution when interpreting the relationship between HD and NHL by paraffin immunophenotyping alone.
 ...
PMID:Inconsistency of the immunophenotype of Reed-Sternberg cells in simultaneous and consecutive specimens from the same patients. A paraffin section evaluation in 56 patients. 135 42

A 77-year-old woman with primary esophageal non-Hodgkin's lymphoma in clinical stage IEA (Ann Arbor Classification) developed pain and difficulty in swallowing. An upper gastrointestinal examination revealed a submucosal tumor from the upper to the middle portion of the esophagus. Histopathological examination at endoscopic biopsy with endoscopic partial incision showed non-Hodgkin's lymphoma (diffuse type--large cell). Immunohistological examination of tumor cells disclosed LCA (+), CD3(DAKO) (+), MT1 (+), UCHL1 (+), MB1 (+), MxPanB (-) and EMA (-) reactivity and showed T cell lymphoma. The clinical stage was determined to be IEA after further work-up. Improvement of swallowing difficulty and esophageal findings on upper gastrointestinal series were noted after modified CHOP therapy and radiotherapy (total 50 Gy).
 ...
PMID:Primary esophageal non-Hodgkin's lymphoma. 163 71

Monoclonal antibodies (mAbs) directed against the leucocyte common (CD45) antigen have been proposed as a useful tool for the differential diagnosis between malignant lymphomas (CD45+) and poorly differentiated nonhemopoietic tumors (CD45-). Thanks to the availability of mAbs directed against fixative-resistant epitopes of the CD45 molecule, this distinction can now easily be made even in routinely processed tissues. However, a small percentage of morphologically poorly defined neoplasms are difficult to diagnose even with the help of immunohistochemistry. The investigators report that 63 out of 165 anaplastic large-cell (ALC) lymphomas did not show any reactivity for the CD45 antigen in paraffin sections. In routine biopsies, the lymphomatous nature of these cases, most of which had been sent for consultation, could be always unequivocally established by demonstrating negativity for cytokeratins (mAb KL1) and clear dot-like and/or surface reactivity with the Ber-H2 mAb, which is directed against a fixative-resistant epitope of the lymphoid cell activation antigen CD30. Strikingly, 54% of the CD45-cases reacted with mAbs directed against fixative-resistant epitopes of the T cell-restricted CD45RO antigen (mAb UCHL1) or the B-restricted molecules CD45RA (mAb 4KB5) and L26 (unclustered). In order to avoid confusion of ALC lymphomas with anaplastic nonlymphoid tumors, pathologists must be aware of the existence of CD30+/CD45- ALC lymphomas, as they can mimic the above-mentioned malignancies both morphologically (due to the sinusoidal growth pattern) and phenotypically (due to the expression of EMA). The investigators conclude that the combined use of mAbs directed against fixative-resistant epitopes of the CD30, CD45RO, CD45RA, and L26 antigens and cytokeratins is essential for the correct diagnosis and treatment of these equivocal cases.
 ...
PMID:Variable expression of leucocyte-common (CD45) antigen in CD30 (Ki1)-positive anaplastic large-cell lymphoma: implications for the differential diagnosis between lymphoid and nonlymphoid malignancies. 169 92

Lymph node biopsies from 57 local and referred cases, previously diagnosed at Southampton between 1978 and 1987 as lymphocyte predominance Hodgkin's disease were examined using the monoclonal antibodies MT1, UCHL1, L26, LN-1, E29/68 (EMA), Leu-M1 (CD15) and Ber-H2 (CD30). Of the 34 cases with a nodular architecture, 21 (19 male, two female) contained polylobated Reed-Sternberg cell variants with a B-cell phenotype, which lacked expression of CD15. In all cases, the polylobated cells showed positive staining with L26 and LN-1. Six cases expressed EMA and three showed positive staining with Ber-H2. Two cases lacking polylobated cells were reclassified as reactive follicular hyperplasia with progressive transformation of germinal centres. The remaining 11 cases had an atypical immunophenotype and were reclassified, mainly as mixed cellularity Hodgkin's disease. In six cases, the lymph node architecture showed a mixture of nodular and diffuse growth patterns. Five of these cases contained polylobated cells with the typical morphology and immunophenotype of those seen in nodular lymphocyte predominance Hodgkin's disease. The sixth case contained cells expressing CD15, and was reclassified as nodular sclerosing Hodgkin's disease. Of the fifteen biopsies with a diffuse architecture, four contained polylobated B-cells lacking expression of CD15. These were considered to be diffuse lymphocyte predominance Hodgkin's disease. The remaining 11 cases were reclassified as either Hodgkin's disease, mixed cellularity or as T-cell lymphomas.
 ...
PMID:Lymphocyte predominance Hodgkin's disease--an immunohistochemical study. 232 37

Reagents that recognize antigens on lymphoid cells in fixed and wax-embedded sections have been applied to a series of cases of non-Hodgkin's lymphomas. The panel consisted of MB1, 4KB5 (CD45r), LN1, L26 and MB2 which recognize antigens expressed predominantly on B-lymphocytes; UCHL1 and MT1 which recognize antigens expressed on T-lymphocytes and myeloid cells; antibodies recognizing the non-lineage antigens LeuM1 (CD15), BerH2 (CD30), anti-EMA; anti-lysozyme and MAC 387 which detect antigens present on some macrophages; and finally TAL1B5 (class II MHC), CAM 5.2 (low molecular weight cytokeratin) and PD7/26 + 2B11(CD45). Two hundred and four cases of non-Hodgkin's lymphoma have been studied, of which 158 had been fully characterized on frozen sections. The series was biased towards high-grade (n = 108) and T-cell (n = 44) tumours and these were largely prospectively accrued. It was found that discrimination between B-cell and T-cell lymphomas can be reliably achieved using these reagents and that a small panel (CD45, L26, MB2, MT1, UCHL1) is adequate for this purpose. Using the full range of reagents it is not possible to subdivide cases into groups that correspond with morphological subtypes of lymphoma. Although paraffin section immunohistochemistry is of value, the diagnosis of lymphoproliferative disorders must still be based upon the assessment of well fixed, carefully prepared tissue sections using conventional tinctorial methods.
 ...
PMID:Paraffin section immunohistochemistry. I. Non-Hodgkin's lymphoma. 326 64

Primary malignant lymphomas (ML) of the thyroid are rare and their conclusive morphologic diagnosis is not always possible. The authors report diagnostic features of 11 cases of ML and one case of plasmacytoma of thyroid compared with chronic lymphocytic thyroiditis and undifferentiated carcinomas of thyroid in an immunohistochemical study using monoclonal antibodies (MoAb). The lymphoid nature of tumors could be identified in all cases with three MoAb on paraffin sections. In ML, tumor cells expressed leucocyte common antigen (Dako-LC+) with negativity for epithelial membrane antigen (Dako-EMA-) and cytokeratin (KL1-). Newer MoAb identifying B-cell (LN-1, LN-2, MB2) and T-cell-associated antigens (MT1, UCHL1) not denatured by fixation, revealed B-cell nature of tumor cells in all cases of ML. Among anti-B MoAb, LN-1 and MB2 were most consistent in their reactivity. In cryostat sections of three ML cases, the tumor cells expressed one or more B-cell-associated antigens. Plasmacytoma was negative for Dako-LC and KL1 but positive for Dako-EMA and monotypic cytoplasmic Ig.
 ...
PMID:Diagnostic features of primary malignant lymphomas of the thyroid with monoclonal antibodies. 328 44

Formalin fixed and paraffin wax embedded tissue from 24 cases of T-cell lymphoma diagnosed using immunocytochemistry on cryostat sections was examined using a panel of eight monoclonal and three polyclonal antisera. The monoclonal antibodies UCHL1 and MT1 proved to be comparable and reliable markers of neoplastic cells in T-cell lymphomas. The B-cell specific marker, MB1, strongly stained all cells in two cases of pleomorphic large cell T-cell lymphoma, large cells in two cases of pleomorphic mixed medium and large cell lymphoma, and isolated clusters of blast cells in four cases of T-zone and angioimmunoblastic lymphadenopathy-like T-cell lymphoma. The cells stained by MB1 expressed T suppressor/cytotoxic surface markers on frozen section. Epithelial membrane antigen, as detected by a polyclonal anti-EMA and the monoclonal antibody HMFG2, was expressed in 36% of tumours especially those of monomorphic large cell and pleomorphic large cell phenotype. Single granules or finely dispersed cytoplasmic granularity was seen in four tumours using the anti-granulocyte reagent Leu M1. Tumour cells in one case stained in a pattern identical to Reed-Sternberg cells in Hodgkin's disease. Granular alpha-1-antitrypsin staining was found in 10 cases of pleomorphic large cell and monomorphic large cell lymphoma. No staining was observed using anti-lysozyme or the monoclonal macrophage specific marker Mac411. Monomorphic and pleomorphic large cell lymphomas tended to show a common immunophenotype with the majority of cells co-expressing alpha-1-antitrypsin HLA-DR and epithelial membrane antigen. Scattered large transformed blast cells in cases of angioimmunoblastic lymphadenopathy-like T-cell lymphomas and T-zone lymphomas shared a similar immunophenotype with the large cell lymphomas. Using a panel of monoclonal antibodies effective in paraffin embedded tissue, diagnostically useful staining profiles which correlate with the morphological phenotype can be established in T-cell lymphomas.
 ...
PMID:An immunocytochemical study of T-cell lymphomas using monoclonal and polyclonal antibodies effective in routinely fixed wax embedded tissues. 354 52

Although immunophenotypic abnormalities have been reported in B-cell non-Hodgkin's lymphomas (NHLs) occurring in the general population, there are no extensive studies on such abnormalities in AIDS-related B-cell NHLs. Reactivity of CD45RO/UCHL1 and expression of other T-cell associated antigens (CD43, OPD4, CD3, CD5, EMA) were examined by immunohistochemistry in 66 diffuse aggressive AIDS-related B-cell NHLs and in 296 AIDS-unrelated B-cell NHLs of similar morphology analyzed in the same institution. EBER in situ hybridization studies were also carried out in 57 of the 66 AIDS-related B-cell NHLs investigated. CD45RO/UCHL1 was expressed in 27% of AIDS-related B-cell NHLs, but only in 8% of diffuse aggressive AIDS-unrelated B-cell NHLs. The difference was highly significant (P < .001) overall and, within the Working Formulation subtypes, especially marked among small noncleaved cell (SNCC) lymphomas. Conversely, the reactivity of other T-cell associated antigens seemed to be very similar in AIDS-related and AIDS-unrelated NHLs. However, for CD43, a significantly lower number of positive cases was found in AIDS-related NHLs among SNCC lymphomas. Among AIDS-related B-cell NHLs, the highest frequency of CD45RO/UCHL1 expression was found in the immunoblastic subset with plasmacytoid differentiation. In the latter CD45RO/UCHL1 preferentially associated with EMA expression and EBV infection of the tumor clone, but not with CD45RA. The present finding of an excess of CD45RO/UCHL1 expression in AIDS-related B-cell lymphomas may reflect the preferential expansion of CD45RO expressing B-cell clones with putative autoreactive potential, as suggested by the expansion of CD45RO expressing B-cells in autoimmune disorders.
 ...
PMID:High frequency of CD45RO expression in AIDS-related B-cell non-Hodgkin's lymphomas. 852 13

Systemic anaplastic large-cell lymphoma is an uncommon type of non-Hodgkin lymphoma characterized by strong expression of the Ki-1 (CD30) antigen. Gastrointestinal involvement typically is less common than in other types of non-Hodgkin's lymphoma. We report a case of CD30-positive anaplastic large-cell lymphoma occurring at the site of colonic anastomosis in an elderly patient who had been treated for colonic adenocarcinoma by right hemicolectomy 10 years previously. The lymphoma was a 2-cm mass composed of large, atypical cells infiltrating the mucosa, submucosa, and muscularis propria. Immunoperoxidase stain was strongly positive for Ki-1, and negative for LeuM1, L26, UCHL1, EMA, and cytokeratin. There have been numerous reports of unusual extranodal presentations of systemic anaplastic large-cell lymphoma; the only previously reported case involving the colon, however, occurred in the context of ulcerative colitis. Anastomotic recurrence is a relatively common complication of surgical therapy for adenocarcinoma, but the recurrent tumors are invariably adenocarcinomas. We are aware of no cases of lymphoma of any type occurring at the site of anastomosis after resection for adenocarcinoma.
 ...
PMID:Ki-1 anaplastic large-cell lymphoma occurring at the site of ileocolonic anastomosis in a patient treated surgically for colonic adenocarcinoma: case report and review of the literature. 1143 70


1 2 Next >>