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Query: UMLS:C0019829 (Hodgkin's disease)
 30,247 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Five cases of intravascular lymphomatosis (IVL) are reported. Diffuse or focal cerebral signs suggestive of vascular disease occurred in four cases, but case 5 presented with symptoms similar to Creutzfeld-Jakob disease. Clinical course ranged from two to eight months and diagnosis was made in all cases by autopsy. Neoplastic lymphoid cells mainly lodged in lumina of small vessels in many organs, but infarction was confined to the CNS. Some extravascular tumor cells were regularly seen. All cases corresponded to high-grade Non-Hodgkin lymphomas of B-cell type and displayed high proliferation indices. Different from findings in primary cerebral and nodal lymphomas, neither p53 nor bcl-2 oncoproteins were detectable. Absence of EBV genome and EBV latent membrane protein from IVL was demonstrated for the first time.
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PMID:Intravascular lymphomatosis of the CNS: clinicopathologic study and search for expression of oncoproteins and Epstein-Barr virus. 798 93

Bcl-2 protein was analysed in cell cultures derived from non-Hodgkin lymphomas and chronic lymphocytic leukaemia patients. The presence of bcl-2 proto-oncogene protein product has been demonstrated on cytospin preparations utilising immunochemical methods. The correlation between the expression of the bcl-2 protein and the appearance of proliferation- or differentiation related figures was studied. The reported bcl-2 up regulation in malignant lymphoid cells was confirmed in haemo- and lymphopoietic progenitor cells as well as in TPA/PHA activated peripheral blood lymphocytes. In comparison to neoplastic cells lower intensity of bcl-2 positive staining in freshly isolated cells from non-leukaemic tissue was observed.
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PMID:Studies on bcl-2 protein in cultured lymphoid cells. 801 87

A polymerase chain reaction analysis of biopsy specimens from a total of 52 patients with Hodgkin's disease has revealed the presence of the t(14;18) chromosomal translocation in 14 cases (28%). Twelve involved the major breakpoint region and two included the minor cluster region of the bcl-2 gene. Direct sequencing of the amplified 14q+ junctions from the initial four positive cases (from 21 biopsies) has been previously published and demonstrated the similarity in nature of the break-points to those described in follicular lymphoma and lymphoid hyperplasia. The 52 biopsies have also been studied with a monoclonal antibody to immunolocalize the Bcl-2 protein. In all cases Bcl-2 positivity was observed in the majority of surrounding lymphocytes. However, in 11 cases, positive immunostaining in the Sternberg-Reed cells was also observed. Three of these cases contained the t(14;18) translocation, but 11 cases which were positive for the t(14;18) by PCR did not show Bcl-2 protein staining in the Sternberg-Reed cells. This data confirms the presence of t(14;18) in 28% of biopsies from Hodgkin's disease and demonstrates Bcl-2 protein staining in a variable proportion of Sternberg-Reed cells of some cases.
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PMID:The t(14;18) chromosomal translocation and Bcl-2 protein expression in Hodgkin's disease. 805 70

The bcl-2 gene becomes transcriptionally deregulated in the majority of low-grade non-Hodgkin lymphomas as a result of t(14;18) translocations that place the bcl-2 gene at 18q21 into juxtaposition with the Ig heavy-chain locus at 14q32. This chromosomal translocation or similar bcl-2 gene rearrangements involving the Ig light-chain genes have been reported to occur in some cases of B-cell chronic lymphocytic leukemia (B-CLL). We analyzed the structure, methylation, and expression of the bcl-2 gene in 20 cases of B-CLL or closely related variants of this lymphoproliferative disorder, including at least 16 typical examples of CD5+ B-CLL. None of the 20 specimens had evidence of bcl-2 gene rearrangements, based on Southern blot analysis using three different bcl-2 probes. However, immunoblot analysis using antibodies specific for the Bcl-2 protein showed that 14 of 20 cases (70%) contained levels of p26-Bcl-2 that were equal to or greater than those found in a t(14;18)-bearing lymphoma cell line. Furthermore, in 19 of 20 cases (95%), the Bcl-2 protein was present at levels that were 1.7- to 25-fold higher than in normal peripheral blood lymphocytes. These differences in the relative levels of Bcl-2 protein among cases of B-CLL appeared to be functionally significant, in that a preliminary analysis of 3 representative cases showed that CLL cells with higher levels of Bcl-2 protein survived longer in culture and were delayed in their onset of DNA degradation relative to CLL cells with lower Bcl-2 protein levels. Evaluation of the methylation status of the bcl-2 gene using the isoschizomers Msp I and Hpa II, and a probe corresponding to the first major exon of the gene showed complete demethylation of both copies of the bcl-2 gene in a region corresponding to a 2.4-kb Msp I fragment in all 20 cases of B-CLL. In contrast, analysis of 6 of 6 B-cell lines that harbor a t(14;18) was consistent with hypomethylation of only one of the two bcl-2 alleles. Neither copy of the bcl-2 gene was demethylated in this region in 5 of 5 lymphoid cell lines that lack this translocation. However, hypomethylation of the bcl-2 gene did not necessarily correlate with the relative levels of Bcl-2 protein present in the B-CLL cells, suggesting that additional mechanisms for regulating bcl-2 expression are involved.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:bcl-2 gene hypomethylation and high-level expression in B-cell chronic lymphocytic leukemia. 810 32

The interchromosomal 14;18 translocation occurs in approximately 70-80% of follicular lymphomas and in a lower proportion of high-grade non-Hodgkin lymphomas of the lymph nodes. This translocation results in the fusion of the bcl-2 oncogene on chromosome 18 with immunoglobulin heavy chain genes on chromosome 14, and in the expression of higher amounts of normal bcl-2 protein. We studied bcl-2 expression in biopsies of 108 patients with benign and malignant cutaneous lymphoproliferative diseases (B-cell lymphoma, primary cutaneous, 42; secondary cutaneous, 21; primary cutaneous T-cell lymphoma, 21; B-cell pseudolymphoma, 24), using a monoclonal anti-bcl-2 antibody on paraffin-embedded tissue sections, bcl-2 protein was detected immunohistochemically in 16 of 63 cases of cutaneous B-cell lymphoma, whereas cutaneous T-cell lymphomas and B-cell pseudolymphomas were negative. The proportion of bcl-2 protein expression was significantly higher in secondary (11/21) than in primary cutaneous B-cell lymphomas (5/42; chi 2 test, p < 0.001). Biopsies from 25 of these patients (B-cell lymphoma, 22; B-cell pseudolymphoma, three) were analyzed previously on the molecular level for the t(14;18), using polymerase chain reaction amplification of DNA obtained from paraffin-embedded sections. In four of 11 cases of bcl-2 protein-positive B-cell lymphoma (primary, one; secondary, three) the t(14;18) was detected by polymerase chain reaction. All other cases of B-cell lymphoma, including seven cases where bcl-2 protein was detected by immunohistology, and B-cell pseudolymphoma were negative. These results demonstrate: 1) bcl-2 protein is expressed in a small portion of cutaneous B-cell lymphomas; 2) bcl-2 protein expression is significantly more frequent in secondary than in primary cutaneous B-cell lymphoma; 3) only approximately one-third of cases expressing the bcl-2 protein are characterized also by the t(14;18). bcl-2 protein expression might indicate that the cutaneous manifestation of the lymphoma represents a secondary spread from a node-based lymphoma.
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PMID:bcl-2 protein expression and correlation with the interchromosomal 14;18 translocation in cutaneous lymphomas and pseudolymphomas. 810 52

Follicular lymphomas comprise almost two thirds of the US adult non-Hodgkin's lymphomas (NHL) and are the most common malignancy of B-lineage lymphocytes. Polymerase chain reaction (PCR) protocols have been developed to detect the t(14;18) translocation, which juxtaposes the bcl-2 proto-oncogene to the Ig heavy-chain (IgH) gene in 85% of follicular lymphomas and monoclonal rearrangements of the IgH gene in B-cell NHL that lack bcl-2 rearrangements. We used PCR to amplify bcl-2 and IgH rearrangements in DNA from patients with lymphoproliferative disorders and analyzed the products in parallel by gel electrophoresis and flow cytometry, which detected PCR products incorporating fluoresceinated oligonucleotide primers by sequence-specific capture to oligonucleotide-coated magnetic beads. Overall, flow cytometry was superior to electrophoresis of ethidium-bromide-stained agarose gels for detection of products of nested PCR to detect intergenic rearrangements involving bcl-2 and single primer-pair amplification of clonal rearrangement of IgH. Flow cytometric analysis detected bcl-2 translocations in 12 of 13 CD10+ B-cell lymphomas and clonal IgH rearrangements in 14 of 17 monoclonal B-cell populations. In contrast, analysis by gel electrophoresis detected bcl-2 translocations in only 10 of 13 CD10+ and clonal IgH gene rearrangements in only 9 of 17 monoclonal B-cell populations. Flow cytometric analysis was more sensitive than gel electrophoresis and could detect a 16-fold greater dilution of a bcl-2-amplified product than gel electrophoresis. Similarly, flow cytometry could detect an amplification product when template DNA was diluted 10,000-fold, whereas gel electrophoresis only detected amplification products when template was subjected to dilution between 100- and 1,000-fold. This shows the utility of flow cytometry for the analysis of DNA amplification products incorporating fluorochrome-labeled primers as a rapid, objective alternative to conventional strategies. Because current-generation clinical laboratories emphasize automation, flow cytometric analysis of PCR-amplified products shows increased analytic sensitivity and offers a vehicle for automation of DNA amplification tests.
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PMID:Cytometric detection of DNA amplified with fluorescent primers: applications to analysis of clonal bcl-2 and IgH gene rearrangements in malignant lymphomas. 811 Oct 48

Waldeyer ring lymphomas belong to a category of tumours which has not yet been fully defined. Their relation to mucosa-associated lymphoid tissue (MALT) and other extranodal lymphomas remains largely unknown. We performed a clinicopathological retrospective study of 79 patients, and compared them with a series of MALT and nodal lymphomas. Tumours from the nasopharynx and palatine tonsil showed similar histological profiles, with a predominance of large B-cells. Centroblastic lymphomas constituted the largest group (n = 45), followed by those of centrocytic type (9) with smaller groups of centroblastic-centrocytic (5) and Hodgkin's lymphomas (2). Three monocytoid B-cell lymphomas were identified. Only one case could be classified as MALT lymphoma. The frequency of bcl-2 expression in large B-cell tumours of Waldeyer's ring has an intermediate range between large B-cell lymphomas occurring in mucosal and nodal locations. Epitheliotropism was present in all low-grade cases, and was therefore not a useful marker in the identification of potential MALT lymphomas in contrast with other mucosal sites. Comparative survival studies showed significant overall differences between Waldeyer ring lymphomas, MALT and nodal cases. These disappeared after taking stage and histological grade into account. We conclude that Waldeyer ring lymphomas show distinctive features, mainly in terms of histological distribution and immunophenotype. The key factor determining their behaviour could be their different spreading capability. These findings suggest that extranodal lymphomas are heterogeneous, and indicate the need for additional efforts to clarify this.
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PMID:Waldeyer ring lymphomas. A clinicopathological study of 79 cases. 814 51

Seven cases of large cell lymphoma (LCL) developing simultaneously or secondarily to lymphocyte-predominant Hodgkin's disease (nodular paragranuloma [NP]) were investigated for the presence of Epstein-Barr virus genomic material and the chromosomal translocation t(14;18) involving the major breakpoint region of the bcl-2 gene using the polymerase chain reaction on paraffin-embedded material. The translocation t(14;18) and Epstein-Barr virus could not be demonstrated in any case. The expression of the bcl-2 oncogene product was investigated using immunohistochemistry. Only in one case were the lymphocytic and histiocytic cells positively stained with the bcl-2 antibody, whereas the associated LCL demonstrated a completely negative immunoreaction. In another case the LCL had a positive immunoreaction with this antibody and the corresponding lymphocytic and histiocytic cells were completely negative. We conclude that Epstein-Barr virus infection is rare or absent in NP and in the LCLs associated with NP. The chromosomal translocation t(14;18) does not seem to be a factor in the transformation of NP into LCL.
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PMID:Incidence of Epstein-Barr virus bcl-2 expression and chromosomal translocation t(14;18) in large cell lymphoma associated with paragranuloma (lymphocyte-predominant Hodgkin's disease). 815 Apr 54

To determine whether correlations existed between morphologic and immunophenotypic findings and clinical characteristics, 30 cases of T-cell-rich large B-cell lymphomas (TBL) were evaluated by histopathology, immunostaining, and polymerase chain reaction on paraffin-embedded material. All were characterized by a polymorphic cell composition, including a variable mixture of small and large lymphoid cells and reactive cell. Most cases (87%) fitted into one of three main histologic types of non-Hodgkin's lymphoma (diffuse, mixed cell; diffuse, large cell; follicular and diffuse, mixed cell), and one group of eight cases had the prototypic features described by Ramsay et al. (17). All cases showed a component of large CD20(L26)+ MB2+ B cells in a predominant back-ground of reactive T cells (> 50% of the total lymphoid forms). Clonality was demonstrated by light chain restriction in 67% of cases and by rearrangement of the immunoglobulin heavy chain gene and bcl-2 gene in 64% and 28% of cases, respectively. The patients were predominantly men (70%), ages 18-83 years (median of 62.5), and were initially seen predominantly with nodal disease (and extranodal involvement in 20%) at advanced stages (III-IV: 77%). Treatment was mostly aggressive chemotherapy, and the outcomes were favorable (84% alive and well). These features are not distinctive as compared with those of typical large-cell lymphoma, nor did subgroups within the series (prototypic cases versus others; cases with less [< or = 70%] or more [> 70%] T-cell infiltration) significantly differ in clinical presentation or outcome. Thus, this study confirms that TBL, while useful as a diagnostic variant to be distinguished from both peripheral T-cell lymphoma and Hodgkin's disease, is a heterogeneous assortment of diverse histopathologic categories rather than a clinicopathologic entity. The term "T-cell rich" might, however, be usefully retained as a morphologic specification to be added to recognized histologic categories of lymphoma.
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PMID:T-cell-rich large B-cell lymphoma. A study of 30 cases, supporting its histologic heterogeneity and lack of clinical distinctiveness. 779 83

The chromosomal translocation t(14;18)(q32;q21), which involves the bcl-2 oncogene, occurs in most follicular lymphomas. Recent evidence suggests that this translocation occurs in Hodgkin's disease, linking its cellular origin and oncogenesis to follicular non-Hodgkin's lymphomas. Using polymerase chain reaction, the authors examined both Hodgkin's disease (n = 60) and reactive lymph nodes (n = 34) for the presence of bcl-2/JH breakpoint fragments, which are indicative of the t(14;18) chromosomal translocation in the major breakpoint region of the bcl-2 gene. The translocation was detected in approximately 10% of both Hodgkin's disease and nonmalignant reactive lymph node cases. These results suggest the possibility that the translocation may occur in the reactive component of Hodgkin's disease and not in the putative malignant cells, the Reed-Sternberg cells. Furthermore, the detection of the translocation in reactive lymph nodes suggests that it may not be the primary factor in the oncogenesis of follicular lymphoma.
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PMID:Bcl-2 rearrangement in Hodgkin's disease and reactive lymph nodes. 820 65


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