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Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

B-cell clonality detection in whole tissue is considered indicative of B-cell non-Hodgkin lymphoma (NHL). We tested frozen tissue of 24 classical Hodgkin lymphomas (cHL) with a varying tumor cell load with the multiplex polymerase chain reaction (PCR) primer sets for IGH and IGK gene rearrangement (BIOMED-2). A clonal population was found in 13 cases with the IGH FR1 and/or FR2/FR3 PCRs. Using the IGK-VJ and IGK-DE PCRs, an additional six cases had a dominant clonal cell population, resulting in a detection rate of 79% in frozen tissue. Of 12 cases, also the formalin-fixed and paraffin-embedded (FFPE) tissue was tested. Surprisingly, in eight of the 12 FFPE cases with acceptable DNA quality (allowing PCR amplification of >200 nt fragments), the IGK multiplex PCRs performed better in detecting clonality (six out of eight clonal IGK rearrangements) than the IGH PCRs (four out of nine clonal rearrangements), despite a rather large amplicon size. There was no evidence of B-cell lymphoma during follow-up of 1 to 6 years and no correlation was found between the presence of a clonal result and Epstein-Barr virus in the tumor cells. Our results indicate that the present routine PCR methods are sensitive enough to detect small numbers of malignant cells in cHL. Therefore, the presence of a clonal B-cell population does not differentiate between cHL and NHL.
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PMID:PCR clonality detection in Hodgkin lymphoma. 1966 21

The BCL2/IGH translocation is a hallmark of follicular lymphoma and germinal center B-cell type diffuse large B-cell lymphoma. Although a strong determinant of these histological subtypes, this translocation is insufficient by itself for lymphomagenesis, so that other genetic alterations are required. To clarify how the BCL2 translocation contributes to the development of specific lymphoma subtypes, we used chimeric mouse models and a bone marrow transplantation system to examine the biological features of BCL2-overexpressing B cells. These cells showed a cell-autonomous differentiation preference for follicular B cells. Their cell cycle progression was enhanced in wild-type but not in Emu-BCL2 transgenic mice, indicating that the low proliferative activity of B cells in Emu-BCL2 transgenic mice is partly due to their specific microenvironment, which is caused by the abnormal B cells themselves. Moreover, in vitro experiments demonstrated that Emu-BCL2(+) B cells have reduced responsiveness to terminal differentiation stimulation. According to these results, we hypothesize that B cells that have undergone BCL2/IGH translocation might possibly be forced to localize in follicles, and accumulate genetic abnormalities by being subjected to recurrent stimulation. Our findings lead us to propose that B cells carrying the BCL2/IGH translocation comprise a distinctive cell population that leads to the development of germinal center B-cell type lymphoma.
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PMID:Distinctive cell properties of B cells carrying the BCL2 translocation and their potential roles in the development of lymphoma of germinal center type. 1978 Jul 57

Helicobacter pylori (H. pylori) is a gram-negative helical rod that colonizes human gastric mucosa. Its discovery has opened up new opportunities regarding the understating and management of gastrointestinal disorders. In humans, infection with H. pylori has been established as a major cause of chronic gastritis and peptic ulcer, and is important in the pathogenesis of gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Bacterial and host factors determine the outcome of H. pylori infection. The eradication of H. pylori can, therefore, contribute to the treatment and prevention of these diseases. H. pylori infection plays a critical role in gastric carcinogenesis through two major pathways: the indirect action of H. pylori on gastric epithelial cells through inflammation, and the direct action of the bacteria on epithelial cells through the induction of protein modulation and gene mutation. MALT lymphoma is a common low grade B-cell lymphoma arising from a background of chronic inflammatory disease at a number of mucosal sites. Those originating in the stomach are causatively linked to H. pylori infection, and eradication of the bacterium with antibiotics leads to the long-term complete regression of lymphoma. t (11;18)/API2-MALT1 and t(1;14)/IGH-BCL10 are specifically associated with the gastric MALT lymphoma entity, and the oncogenic products of these translocations have been shown to target a common molecular pathway, i.e., the nuclear factor-kappaB pathway. This paper reviews recent advances in our understanding of the association of H. pylori infection with gastric cancer and gastric MALT lymphoma and the molecular genetics underlying tumor development.
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PMID:[Crucial roles of Helicobacter pylori infection in the pathogenesis of gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma]. 1986 Feb 12

The recent topics in the treatment and genetic aberrations of gastric MALT lymphoma were reviewed. The chromosomal translocation t(11;18) (q21;q21)/API2-MALT1 has been frequently detected not only in gastric MALT lymphoma cases, but also in gastric diffuse large B-cell lymphoma (DLBCL) cases in two studies. Conversely, IGH-involved translocations, including t(3;14) (p14;q32)/FOXP1-IGH, are rarely seen in gastric MALT lymphoma. Several large-scaled clinical series have revealed that Helicobacter pylori eradication therapy is the optimal first-line treatment for patients with gastric MALT lymphoma, which leads to a favorable long-term outcome. A number of modalities and/or regimens, including chemotherapy, immunotherapy, and radioimmuotherapy, have been developed as the second-line treatments for patients not responding to eradication therapy.
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PMID:[Gastric MALT lymphoma: recent topics regarding treatment and genetic aberrations]. 1999 20

Primary cutaneous marginal zone lymphoma (MZL) is a common B-cell lymphoma of skin and is characterized by an infiltrate of neoplastic marginal zone B cells typically within the marginal zones of reactive lymphoid follicles and the interfollicular region. However, in our experience, many cases have underemphasized features such as marked plasmacytic differentiation and/or a prominent T-cell component, which may obscure the neoplastic B cells and lead to misdiagnosis. We wanted to draw attention to these features and have studied 15 cases of MZL with marked plasmacytic differentiation, 10 of which had numerous T cells, some with cytologic atypia, and few B cells in the interfollicular region. Plasma cells were monotypic in all cases by in situ hybridization. By polymerase chain reaction, 6 of 8 T cell-rich cases had an IGH gene rearrangement, and none were clonal for T-cell receptor gene. We discuss the terminology, morphologic features, molecular profile, behavior, and differential diagnosis of cutaneous MZL.
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PMID:Characteristics of cutaneous marginal zone lymphomas with marked plasmacytic differentiation and a T cell-rich background. 2002 59

D-cyclin proteins play a central role in cell-cycle regulation and are involved in the pathogenesis of lymphomas. In mantle-cell lymphoma, the t(11;14) translocation leads to overexpression of cyclin-D1, in addition to which cyclin-D1-negative mantle-cell lymphoma that overexpress cyclin-D2 or D3 have also been described. Although cyclin-D2 and D3 have been implicated in the prognosis of specific lymphoma subtypes, a thorough characterization of D-cyclin protein expression in human hematolymphoid neoplasia has not been reported. To evaluate the tissue expression patterns of D-cyclins, particularly D2 and D3, in normal and neoplastic hematolymphoid tissues, we optimized the commercially available antibodies for D-cyclins for use on paraffin-embedded tissue and stained tissue microarrays of over 700 patient samples. Our results show that cyclin-D2 and D3 proteins are expressed in many more lymphoma subtypes than cyclin-D1. Cyclin-D1, D2 and D3 were expressed in 100, 22 and 6% of mantle-cell lymphomas and 2, 49 and 20% of diffuse large B-cell lymphomas. Fluorescence in situ hybridization studies confirmed the presence of the CCND1/IGH translocation in the majority of mantle-cell lymphoma, but not in diffuse large B-cell lymphoma that expressed cyclin-D1 protein. In addition, a subset of follicular, marginal zone, lymphoplasmacytic, lymphoblastic, classical Hodgkin, mature T-cell and natural killer cell lymphomas and acute myeloid leukemias also expressed cyclin-D2 and D3. These data support the hypothesis that dysregulation of cell-cycle control by D-cyclins contribute to the pathogenesis of hematolymphoid neoplasia, and suggest a potential role for these proteins in the prognostic and therapeutic aspects of these diseases. For diagnostic purposes, however, the expression of D-cyclin proteins should be interpreted with caution in the subclassification of lymphoma types.
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PMID:Characterization of D-cyclin proteins in hematolymphoid neoplasms: lack of specificity of cyclin-D2 and D3 expression in lymphoma subtypes. 2006 12

Using inverse polymerase chain reaction, we identified CD44, located on chromosome 11p13, as a novel translocation partner of IGH in 9 of 114 cases of gastric, nongastric extranodal, follicular, and nodal diffuse large B-cell lymphoma (DLBCL). Notably, these translocations involving IGHSmu were detected in follicular lymphomas and exclusively in germinal center B cell-ike (GCB)-DLBCLs. CD44 is not expressed in reactive GC B cells. The IGHSmu/CD44 translocations substitute Smu for the CD44 promoter and remove exon 1 of CD44, resulting in the overexpression of Imu-CD44 hybrid mRNA transcripts activated from derivative 11 that encode a new CD44 variant lacking the leader peptide and with a unique C-terminus (CD44DeltaEx1). When overexpressed in vitro in the CD44(-) GCB-DLBCL cell line BJAB, CD44DeltaEx1-green fluorescent protein localized to the cytoplasm and nucleus, whereas CD44s-green fluorescent protein (standard form) localized to the plasma membrane. The ectopic expression of CD44DeltaEx1 in BJAB cells enhanced their proliferation rate and clonogenic ability, indicating a possible pathogenic role of the translocation.
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PMID:CD44 activation in mature B-cell malignancies by a novel recurrent IGH translocation. 2009 4

B-cell lymphomas with concurrent IGH-BCL2 and MYC rearrangements, also known as "double-hit" lymphomas (DHL), are rare neoplasms characterized by highly aggressive clinical behavior, complex karyotypes, and a spectrum of pathologic features overlapping with Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL) and B-lymphoblastic lymphoma/leukemia (B-LBL). The clinical and pathologic spectrum of this rare entity, including comparison to other high-grade B-cell neoplasms, has not been well defined. We conducted a retrospective analysis of clinical and pathologic features of 20 cases of DHL seen at our institution during a 5-year period. In addition, we carried out case-control comparisons of DHL with BL and International Prognostic Index (IPI)-matched DLBCL. The 11 men and 9 women had a median age of 63.5 years (range 32 to 91). Six patients had a history of grade 1 to 2 follicular lymphoma; review of the prior biopsy specimens in 2 of 5 cases revealed blastoid morphology. Eighteen patients had Ann Arbor stage 3 or 4 disease and all had elevated serum lactate dehydrogenase (LDH) levels at presentation. Extranodal disease was present in 17/20 (85%), bone marrow involvement in 10/17 (59%) and central nervous system (CNS) disease in 5/11 (45%). Nineteen patients were treated with combination chemotherapy, of whom 18 received rituximab and 14 received CNS-directed therapy. Fourteen patients (70%) died within 8 months of diagnosis. Median overall survival in the DHL group (4.5 mo) was inferior to both BL (P=0.002) and IPI-matched DLBCL (P=0.04) control patients. Twelve DHL cases (60%) were classified as B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL, 7 cases (35%) as DLBCL, not otherwise specified, and 1 case as B-LBL. Distinguishing features from BL included expression of Bcl2 (P<0.0001), Mum1/IRF4 (P=0.006), Ki-67 <95% (P<0.0001), and absence of EBV-EBER (P=0.006). DHL commonly contained the t(8;22) rather than the t(8;14) seen in most BL controls (P=0.001), and exhibited a higher number of chromosomal aberrations (P=0.0009). DHL is a high-grade B-cell neoplasm with a poor prognosis, resistance to multiagent chemotherapy, and clinical and pathologic features distinct from other high-grade B-cell neoplasms. Familiarity with the morphologic and immunophenotypic spectrum of DHL is important in directing testing to detect concurrent IGH-BCL2 and MYC rearrangements when a karyotype is unavailable. The aggressive clinical behavior and combination of genetic abnormalities seen in these cases may warrant categorization as a separate entity in future classifications and call for novel therapeutic approaches.
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PMID:B-cell lymphomas with concurrent IGH-BCL2 and MYC rearrangements are aggressive neoplasms with clinical and pathologic features distinct from Burkitt lymphoma and diffuse large B-cell lymphoma. 2011 70

In recent years it has become increasingly evident that MYC rearrangements are not confined to classical Burkitt lymphoma (BL), but also occur in diffuse large B-cell lymphoma (DLBCL) and in the new subtype, "B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL" (BCLU), which was recently described in the 2008 revision of the World Health Organization classification. The accurate identification of MYC rearrangements in these three subtypes of high-grade lymphoma is becoming increasingly critical both in terms of diagnosis of classical BL and in light of the prognostic implications in cases of DLBCL and BCLU. We describe three cases of high-grade lymphoma in which cryptic insertion events, resulting in clinically significant IGH-MYC rearrangements, were detectable using an IGH/MYC three-color, dual-fusion fluorescence in situ hybridization (FISH) probe set, but were not detected using break-apart MYC FISH probes, thus highlighting the limitations of using break-apart probes as a stand-alone test, particularly with the increased use of interphase FISH analysis of formalin-fixed, paraffin-embedded tissue sections in the diagnostic work-up of these patients.
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PMID:Detection of cryptic and variant IGH-MYC rearrangements in high-grade non-Hodgkin's lymphoma by fluorescence in situ hybridization: implications for cytogenetic testing. 2030 18

The biologic relationship between small B-cell lymphoma and histiocytic sarcoma (HS) when occurring in the same patient remains unclear, though recent data suggest a possible 'transdifferentiation' from follicular lymphoma (FL) to HS. We investigated the clonal relationship in two cases of small B-cell lymphoma with subsequent HS. Case 1: A 62-year-old female with splenic marginal zone lymphoma (SMZL) developed HS in a groin lymph node 1 year after the primary diagnosis. PCR/sequence analysis of the IGH gene showed a monoclonal rearrangement carrying an identical nucleotide sequence of PCR products from the spleen with SMZL and the lymph node with HS. Case 2: A 61-year-old female with a remote history of FL developed supraclavicular lymphadenopathy, which was confirmed to be HS. PCR analysis of the HS detected a monoclonal rearrangement of the IGH gene and FISH analysis revealed IGH/BCL2 fusion, a genetic hallmark for FL. The transformed HSs showed partial retention of their prior B-cell lymphomas' signatures, including expression of OCT2 in both cases and expression of BCL6 and enhanced expression of BCL2 in case 2. Both HSs demonstrated hypermutated IGH variable regions, arguing against a common progenitor mechanism of the transformation process. The data suggest a common clonal origin of B-cell lymphoma and subsequent HS occurring in the same patient, indicating that 'transdifferentiation' occurs in other small B-cell lymphomas, in addition to the previously reported FL or B-cell lymphoma with IGH/BCL2.
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PMID:Histiocytic sarcoma arising in indolent small B-cell lymphoma: report of two cases with molecular/genetic evidence suggestive of a 'transdifferentiation' during the clonal evolution. 2038 55


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