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

Focal follicular features in diffuse large B-cell lymphomas (DLBCLs) are bound to raise the question of follicular lymphoma (FL) with diffuse areas, because the diagnosis of FL is based on the presence of follicular areas, even though focal. We report 7 cases of primary tonsillar DLBCLs with focal follicular features that presented with morphologic, immunohistochemical, and biological features distinct from those of FL. Histologically, these tumors were characterized by involvement of pericryptal follicles with adjacent dominant diffuse areas. Monomorphous large tumor cells were evenly spaced with abundant, often clear cytoplasm, and blastoid nuclei often with a delicate nuclear membrane. Importantly, residual germinal centers (GCs) were present in the form of either an intrafollicular GC remnant or an isolated GC in the midst of diffuse tumor. An extrafollicular and/or parafollicular growth pattern was also observed. Bcl-6 staining revealed a predominantly sporadic occurrence of Bcl-6(+) cells, comprising <50% of tumor cells, and none displayed diffusely dense collections (>75%) of Bcl-6(+) tumor cells characteristic of the GC or FL. Staining for CD10 was negative in 6 cases. Five of 7 patients were younger than 60, the median age of other patients with primary tonsillar DLBCL. No extratonsillar involvement was seen at 18 months after diagnosis. After chemotherapy or radiotherapy, complete remission was achieved with ease in all patients, but 2 patients who were treated with chemotherapy alone relapsed at 24 and 30 months. In conclusion, tonsillar DLBCL includes a small (10%) but distinct subgroup that warrants distinction from FL with predominant diffuse areas or de novo DLBCL. It appears that the focal follicular features in tonsillar DLBCL likely represent follicular colonization of marginal zone B-cell lymphoma, probably high-grade, if the possibility of FL is excluded.
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PMID:Focal follicular features in tonsillar diffuse large B-cell lymphomas: follicular lymphoma with diffuse areas or follicular colonization. 1219 25

It is reported that overexpression of hnRNP A2 and B1 proteins is useful for detecting early cancers, and that B1, a splicing minor isoform of A2, is more specific than A2. The B1 expression is still undetermined in human lymphoid tissues. We quantitatively studied the B1 expression in 85 lymph node specimens, comprising reactive lymphoid hyperplasia (RLH; n=8), B-cell lymphoma (n=23), T-cell lymphoma (n=22), and metastatic carcinoma (n=32). Immunostaining and immunoblotting analyses with an anti-B1 monoclonal antibody, 2B2 were performed, and the two sets of results correlated with each other (p<0.05). In RLH specimens, B1 expression rate was significantly higher in follicular centers (FC; 44%) than in mantle zone (MZ; 15%) and paracortex (16%) (p<0.01). B1 expression was statistically higher in B-cell lymphoma than in T-cell lymphoma (p<0.01). In B-cell lymphomas, B1 expression rates were 51% in diffuse large B-cell lymphoma (DLBL; n=5) and 45% in follicular lymphoma (FL; n=16), and they were almost the same as that of the FC. Especially in DLBLs, CD10+ FC-origin lymphomas expressed greater amount of B1 than CD10- non-FC-origin lymphomas. B1 expression rate was low in mantle cell lymphoma (MCL; n=2) and similar to that of MZ in RLH. These results suggest that B1 expression is associated with differentiation in lymphoid tissue rather than transformation. B1 expression increases during the process of B-cell differentiation in the FC, and that high B1 expression is maintained in B-cell lymphomagenesis, especially in cells of FC-origin DLBL.
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PMID:Overexpression of heterogeneous nuclear ribonucleoprotein B1 in lymphoproliferative disorders: high expression in cells of follicular center origin. 1237 Jul 41

This study analyzes the pathologic and molecular features of 5 cases of primary cutaneous large B-cell lymphoma of the leg (PCLBCL-leg), recently included in the European Organization for Research and Treatment of Cancer (EORTC) classification of primary cutaneous lymphoma. PCLBCL-leg accounts for 5% to 10% of all primary cutaneous B-cell lymphoma (PCBCL), usually affects elderly patients and carries a worse prognosis than other forms of PCBCL. It has been proposed that the malignant cells of PCLBCL-leg originate from germinal center (GC)-related cells, but their effective normal counterpart is unclear, and the rationale behind the inclusion of this lymphoma as a separate entity is based on its prognosis rather than on its proved histogenesis. All of our cases of PCLBCL-leg morphologically resembled diffuse large B-cell lymphoma (DLBCL), but to better define their histogenesis, we also analyzed various phenotypic and genotypic markers, including mutations of the Ig and of BCL-6 genes, as well as expression of the bcl-6, MUM1, and CD138/syndecan-1 proteins. Immunohistochemically, all of our cases stained for the L-26/CD20cy and CD79a antigens and expressed the bcl-2, bcl-6, and MUM-1 proteins but were negative for both the CD10/CALLA and CD138 antigens. With respect to molecular analysis, the lymphoma population of all PCLBCL-leg carried hypermutation of Ig genes, and all but 1 case also harbored mutations of the BCL-6 gene. Our results indicate that PCLBCL-leg are similar both under the morphofunctional and molecular profiles to most DLBCL of other sites. Thus, caution seems justified before definitely considering PCLBCL of the leg as a distinct entity.
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PMID:Primary cutaneous large B-cell lymphoma of the leg: histogenetic analysis of a controversial clinicopathologic entity. 1237 21

To analyze the relationship between immunophenotyping profile and main clinicopathological features and outcome in diffuse large B-cell lymphoma (DLBCL), we studied 128 patients (59 men, 69 women; median age 65 years) consecutively diagnosed with de novo DLBCL in a single institution. Cells from each patient were immunostained with CD20, CD79a, CD5, CD10, bcl-6, MUM1, CD138, bcl-2, p53, p27, and Ki-67 antibodies. Four immunophenotyping profiles were distinguished according to the pattern of differentiation: germinal center-CD10(+) (GC-CD10(+); CD10(+)/Bcl-6(+)/MUM1(-)/CD138(-)), germinal center-CD10(-) (GC-CD10(-); CD10(-)/Bcl-6(+)/ MUM1(-)/CD138(-)), post-germinal center (pGC; CD10(-)/bcl-6(+/-)/ MUM1(+)/CD138(-)), and plasmablastic (CD10(-)/bcl-6(-)/MUM1(+)/CD138(+)). Rearrangement of bcl-2 was studied by polymerase chain reaction (PCR) in 57 patients. Single-antigen expression was as follows: CD5, 2%; CD10, 21%; bcl-6, 72%; MUM1, 54%; CD138, 2%; bcl-2, 59%; p53, 28%; p27, 40%. Distribution according to differentiation profiles was as follows: GC-CD10(+), 24 patients, GC-CD10-, 30 patients; pGC, 60 patients; plasmablastic, 2 patients; other patterns, 12 patients. The pGC profile was associated with primary nodal presentation and immunoblastic morphology, whereas GC-CD10(+) tumors showed disseminated disease, centroblastic morphology, bcl-2 rearrangement, and lower Ki-67 proliferative index. GC-CD10(-) patients more often presented with primary extranodal origin, early stage, normal lactic acid dehydrogenase (LDH) levels, and low or low/intermediate International Prognostic Index (IPI) scores than the others. However, no significant difference was found in terms of response or overall survival (OS) according to these profiles. Expression of bcl-2 was associated with advanced stage, high or high-intermediate IPI, and poor OS. Expression of bcl-2 maintained predictive value in multivariate analysis, with stage and LDH. In conclusion, differentiation profile was associated with particular clinicopathological features but was not essential to predicting outcome in DLBCL patients.
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PMID:Clinical impact of the differentiation profile assessed by immunophenotyping in patients with diffuse large B-cell lymphoma. 1239 66

Translocations involving the BCL-6 gene are frequently observed in diffuse large B cell lymphoma, but have rarely been reported in follicular lymphoma (FL). We studied a distinct cohort of FLs with a 3q27/BCL-6 gene rearrangement, but lacking the t(14;18) translocation. In 13/15 cases, translocations involved the 3q27 and the 14q32 regions. All cases displayed a marked follicular growth pattern and, in some instances, a monocytoid component. Tumor cells were CD5(-) CD20(+) CD23(-) CD43(-) BCL-6(+), and in the main CD10 negative (n = 10, 71%) and BCL-2 negative (n = 11, 78%). When compared to 20 typical t(14;18)(+) FLs, the presence of large follicles (P = 0.01) and a CD10(-)/BCL-2(-) phenotype were more frequently observed (P = 0.001) in our cohort. Clonal mutations arising in the BCL-6 first intron were observed in 5/7 cases with evidence of intraclonal heterogeneity, consistent with a germinal center origin. No significant difference was found in comparison to t(14;18)(+) FL regarding age, sex, performance status, bone marrow involvement or overall survival. However, in the 3q27(+) FL group, a stage III/IV disease and a bulky mass were less frequently observed. This study indicates that 3q27(+) FL without t(14;18) translocation have peculiar clinico-pathologic features and may correspond to a rare and distinct subtype of lymphoma originating from the germinal center.
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PMID:Follicular lymphoma without t(14;18) and with BCL-6 rearrangement: a lymphoma subtype with distinct pathological, molecular and clinical characteristics. 1239 77

T-cell/histiocyte-rich large B-cell non-Hodgkin's lymphoma (THRLBCL) is an unusual morphologic variant of diffuse large B-cell lymphoma. We reviewed 30 cases of THRLBCL to evaluate its heterogeneity based on morphologic, immunophenotypic, and genetic features. Cases were classified according to the appearance of the large neoplastic B cells into three morphologic variants: 1) lymphocytic and histiocytic (L&H-like) (resembling the L&H cells of nodular lymphocyte predominance Hodgkin's lymphoma (14 cases); 2) centroblast (or immunoblast)-like (10 cases), and 3) Reed-Sternberg cell-like (resembling the neoplastic cells of classic Hodgkin's lymphoma) (6 cases). We used a panel of immunohistochemical stains, including those with specificity for germinal center B cells: CD20, CD79a, CD30, CD15, epithelial membrane antigen, BCL-2, BCL-6, and CD10. The /JH polymerase chain reaction assay was further performed to investigate a relationship to follicular lymphoma. The results were correlated with Epstein-Barr virus status as determined by staining for latent membrane protein and EBER-1 in situ hybridization. All cases were of B-cell immunophenotype with strong surface CD20 reactivity in the neoplastic large lymphoid cells, although CD79a was more inconsistently and weakly expressed (10 of 17). Nuclear positivity for the BCL-6 protein was detected in the tumor cells in 26 of 29 (90%) cases. However, differences in expression of other antigens were encountered in the histologic subtypes. Epithelial membrane antigen positivity, a feature often seen in nodular lymphocyte predominance Hodgkin's lymphoma, was observed in 11 of 30 (37%) cases and was most commonly seen in cases with L&H cell morphology (8 of 14; 57%). CD30 expression was observed in 9 of 30 (30%) cases but was most frequent in cases with Reed-Sternberg-like morphology (3 of 6 [50%]). CD10 expression was infrequent overall (3 of 29; 10%), with 2 of 3 positive cases identified in the centroblastic group. The overall rarity of positivity for CD10, BCL-2 (3 of 22; 13%), and -2 JH rearrangement (1 of 28; 4%) indicates a lack of connection to follicular lymphoma for all subtypes. The three cases that were negative for BCL-6 protein were LMP-1 positive and EBER-1 positive by in situ hybridization, and 2 of 3 had neoplastic cells with Reed-Sternberg-like morphology. These results demonstrate that although a large proportion of THRLBCL represent tumors of germinal center B cell derivation, they exhibit a diversity of morphologic and immunophenotypic features. A subset of THRLBCL may be related to nodular lymphocyte predominance Hodgkin's lymphoma. A small percentage show features closely resembling classic Hodgkin's lymphoma and could be considered a variant of grey zone lymphoma.
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PMID:T-cell/histiocyte-rich large B-cell lymphoma: a heterogeneous entity with derivation from germinal center B cells. 1240 22

A 61-year-old male visited his doctor in October 2000 because of a high fever. Laboratory examination revealed leukocytosis with blast-like cells and thrombocytopenia. He was referred and admitted to our hospital in November 2000. Although he had mild splenomegaly, he had no lymphadenopathy on the first admission. The white blood cell count was 10,520/microliter with 45% blast-like cells and the platelet count was 51 x 10(3)/microliters. Bone marrow aspiration revealed 82% blast-like cells, which were positive for CD5, CD10, CD13, CD19, and CD20. Immunohistochemistry of the bone marrow clot sections revealed blast-like cells were positive for CD5, but negative for TdT, CD23 and cyclin D1. We diagnosed the patient as having de novo CD5-positive diffuse large B-cell lymphoma (DLBCL) with leukemic dissemination. He obtained a complete remission after two courses of CHOP therapy. The third chemotherapy was postponed because of strangulation of the intestine. He relapsed and died in spite of the third chemotherapy. CD5-positive DLBCL is one of the established disease entities that requires an appropriate therapy regimen because it is characterized by elderly onset, extranodal involvement, and a poorer prognosis.
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PMID:[De novo CD5-positive diffuse large B-cell lymphoma with leukemic dissemination diagnosed by immunohistochemical examinations of bone marrow clot sections]. 1246 31

Although primary mediastinal (thymic) large B-cell lymphoma has been primarily studied, its precise phenotype, molecular characteristics, and histogenesis are still a matter of debate. The International Extranodal Lymphoma Study Group collected 137 such cases for extensive pathological review. Histologically, the lymphomatous growth was predominantly diffuse with fibrosis that induced compartmentalized cell aggregation. It consisted of large cells with varying degrees of nuclear polymorphism and clear to basophilic cytoplasm. On immunohistochemistry, the following phenotype was observed: CD45(+), CD20(+), CD79a(+), PAX5/BSAP(+), BOB.1(+), Oct-2(+), PU.1(+), Bcl-2(+), CD30(+), HLA-DR(+), MAL protein(+/-), Bcl-6(+/-), MUM1/IRF4(+/-), CD10(-/+), CD21(-), CD15(-), CD138(-), CD68(-), and CD3(-). Immunoglobulins were negative both at immunohistochemistry and in situ hybridization. Molecular analysis, performed in 45 cases, showed novel findings. More than half of the cases displayed BCL-6 gene mutations, which usually occurred along with functioning somatic IgV(H) gene mutations and Bcl-6 and/or MUM1/IRF4 expression. The present study supports the concept that a sizable fraction of cases of this lymphoma are from activated germinal center or postgerminal center cells. However, it differs from other aggressive B-cell lymphomas in that it shows defective immunoglobulin production despite the expression of OCT-2, BOB.1, and PU.1 transcription factors and the lack of IgV(H) gene crippling mutations.
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PMID:Primary mediastinal B-cell lymphoma: high frequency of BCL-6 mutations and consistent expression of the transcription factors OCT-2, BOB.1, and PU.1 in the absence of immunoglobulins. 1250 7

Discordant bone marrow (BM) involvement in patients with a diagnosis of large-cell non-Hodgkin's lymphoma (NHL) is characterized by marrow infiltrates predominantly composed of small lymphoid cell, cytologically compatible with low-grade NHL. Although this phenomenon is well described morphologically, molecular data concerning the relationship of the two lesions are lacking. The aim of the study was to investigate the clonal relationship of discordant lymphoma manifestations by using immunoglobulin heavy chain gene (IgH), as well as bcl-2 rearrangements, as molecular markers. IgH rearrangements were amplified by PCR with consensus primers directed against framework regions 3 or 2 (FR3 and FR2), followed by automated fragment length analysis and sequencing in selected cases. Rearrangements of the bcl-2 gene were identified with primers against the major breakpoint region. Small BM infiltrates were isolated by laser capture microdissection. In addition, immunohistochemistry was performed on paraffin sections using antibodies against CD3, CD10, CD20, bcl-2, bcl-6, p53, and the Ki67 antigen. Paraffin-embedded tissues of 21 cases diagnosed as diffuse large B-cell lymphoma (DLBCL) with discordant BM involvement and no previous history of low-grade B-cell NHL were analyzed. After review of immunohistochemical stains, 5 cases were excluded either as concordant BM infiltrates by large-cell lymphoma with abundant reactive T-cells (2 cases) or as benign, reactive lymphoid infiltrates (3 cases), as confirmed by a polyclonal pattern in the IgH analysis. Of the remaining 16 cases, a common clonal origin was confirmed in 8 cases by the presence of an identical clonal IgH rearrangement or bcl-2 rearrangement. In 4 cases, identification of distinct IgH or bcl-2 rearrangements gave evidence for the presence of two clonally unrelated neoplasms. The remaining 4 cases were not evaluable for technical reasons. Morphological, phenotypical, and molecular findings were compatible with a lymphoma of germinal center origin in the majority of cases. However, in 4 cases, flow cytometric analysis of the BM infiltrates revealed a B-cell chronic lymphocytic leukemia phenotype. Two of these cases were clonally related to the DLBCL and thus represented Richter's transformation. In summary, discordant BM infiltrates in DLBCL represent a heterogeneous group of disorders, encompassing cases with a clonally related, clinically occult small-cell component, as well as cases with two clonally distinct, unrelated B-cell neoplasms presenting synchronously at different locations.
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PMID:Discordant bone marrow involvement in diffuse large B-cell lymphoma: comparative molecular analysis reveals a heterogeneous group of disorders. 1253 91

In the World Health Organization classification system, splenic marginal-zone lymphoma (splenic MZL) is described as an indolent B-cell lymphoma, which generally presents as splenomegaly with involvement of the bone marrow and peripheral blood. Presence of disease in peripheral lymph nodes and extranodal locations is uncommon. Splenic MZL is characterised by micronodular infiltration of the spleen with marginal-zone differentiation; the immunophenotype is usually IgM+ IgD+/- cytoplasmic-Ig-/+ pan B antigens+ CD5- CD10- CD23- CD43-/+ cyclin D1-; and the most common genetic abnormalities are deletions at 7q22-7q32. Most patients with splenic MZL live for a long time but classic prognostic factors cannot distinguish between patients who are likely to have good and poor outcomes. However, immunological events, such as haemolytic anaemia and immune thrombocytopenia, or the presence of a monoclonal component, are significantly associated with shorter survival. Splenectomy is considered the first-line treatment of choice for splenic MZL; it results in only partial remission, but responses are generally sufficient for correcting cytopenia, improving quality of life, and increasing survival.
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PMID:Splenic marginal-zone lymphoma: a distinct clinical and pathological entity. 1257 51


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