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Therapeutic management and prognostication for patients with B-acute lymphoblastic leukaemia (B-ALL) require appropriate disease subclassification. BCR::ABL1-like B-ALL is unique in that it is defined by a gene expression profile similar to BCR::ABL1+ B-ALL rather than a unifying recurrent translocation. Current molecular/cytogenetic techniques to identify this subtype are expensive, not widely accessible, have long turnaround times and/or require an adequate liquid biopsy. We have studied a total of 118 B-ALL cases from three institutions in two laboratories to identify surrogates for BCR::ABL1+/like B-ALL. We report that immunoglobulin joining chain (IGJ) and spermatogenesis associated serine-rich 2-like (SPATS2L) immunohistochemistry (IHC) sensitively and specifically identify BCR::ABL1+/like B-ALL. IGJ IHC positivity has a sensitivity of 83%, a specificity of 95%, a positive predictive value (PPV) of 89% and a negative predictive value (NPV) of 90%. SPATS2L staining has similar sensitivity and NPV but lower specificity (85%) and PPV (70%). The presence of either IGJ or SPATS2L staining augments the sensitivity (93%) and NPV (95%). While these findings would need to be validated in larger studies, they suggest that IGJ and/or SPATS2L IHC may be utilized in identifying BCR::ABL1-like B-ALL or in selecting B-ALL cases for confirmatory molecular/genetic testing, particularly in resource-limited settings.
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Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Masculino , Humanos , Imuno-Histoquímica , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Translocação GenéticaRESUMO
The ability to detect low-level disease is key to our understanding of clonal heterogeneity in acute myeloid leukemia (AML) and residual disease that elude conventional assays and seed relapse. We developed a high-sensitivity next-generation sequencing (HS-NGS) clinical assay, able to reliably detect low levels (1 × 10-5) of FLT3-ITD, a frequent, therapeutically targetable and prognostically relevant mutation in AML. By applying this assay to 289 longitudinal samples from 62 patients at initial diagnosis and/or clinical follow-up (mean follow-up of 22 months), we reveal the frequent occurrence of FLT3-ITD subclones at diagnosis and demonstrate a significantly decreased relapse risk when FLT3-ITD is cleared after induction or thereafter. We perform pairwise sequencing of diagnosis and relapse samples from 23 patients to uncover more detailed patterns of FLT3-ITD clonal evolution at relapse than is detectable by less-sensitive assays. Finally, we show that rising ITD level during consecutive biopsies is a harbinger of impending relapse. Our findings corroborate the emerging clinical utility of high-sensitivity FLT3-ITD testing and expands our understanding of clonal dynamics in FLT3-ITD-positive AML.
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OBJECTIVES: Although morphologic dysplasia is not typically considered a feature of CCUS, we have consistently observed low-level bone marrow (BM) dysplasia among CCUS patients. We sought to determine whether sub-diagnostic BM dysplasia in CCUS patients is associated with other clinico-pathologic findings of myelodysplastic syndrome (MDS). METHODS: We identified 49 CCUS patients, 25 with sub-diagnostic dysplasia (CCUS-D), and 24 having no dysplasia (CCUS-ND). We compared the clinical, histologic, and laboratory findings of CCUS-D and CCUS-ND patients to 49 MDS patients, including blood cell counts, BM morphology, flow cytometry, cytogenetics, and results of next-generation sequencing. RESULTS: No statistically significant differences were observed between CCUS-D and CCUS-ND patients in the degree of cytopenias, BM cellularity, myeloid-to-erythroid ratio, or the presence of flow cytometric abnormalities. However, compared to CCUS-ND, CCUS-D patients exhibited increased mutations in myeloid malignancy-associated genes, including non-TET2/DNMT3A/ASXL1 variants, spliceosome (SF3B1, SRSF2, ZRSR2, or U2AF1) variants, and IDH2/RUNX1/CBL variants. CCUS-D patients were also enriched for higher variant allele frequencies and co-mutation of TET2/DNMT3A/ASXL1 with other genes. CONCLUSIONS: CCUS-D patients exhibit a molecular (but not clinical) profile more similar to MDS patients than CCUS-ND, suggesting CCUS-D may represent a more immediate precursor to MDS and may warrant closer clinical follow-up.
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Síndromes Mielodisplásicas/diagnóstico , Pancitopenia/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Biópsia , Medula Óssea , Evolução Clonal , Hematopoiese Clonal , Gerenciamento Clínico , Suscetibilidade a Doenças , Feminino , Citometria de Fluxo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/etiologia , Pancitopenia/sangue , Pancitopenia/etiologia , FenótipoAssuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Plasmocitária/diagnóstico , Plasmócitos/patologia , Antígenos CD/análise , Medula Óssea/metabolismo , Medula Óssea/patologia , Deleção de Genes , Humanos , Imunofenotipagem , Cariótipo , Leucemia Plasmocitária/complicações , Leucemia Plasmocitária/genética , Leucemia Plasmocitária/patologia , Masculino , Pessoa de Meia-Idade , Plasmócitos/metabolismo , Proteína Supressora de Tumor p53/genéticaRESUMO
Marginal zone lymphoma (MZL) is a primary, indolent small B-cell lymphoma. Subtypes include nodal, splenic, and those of extranodal mucosa-associated lymphoid tissue (MALT). These are slow growing and generally exhibit low rates of transformation to diffuse large B-cell lymphoma (DLBCL). At initial diagnosis, there can be an increase in large cells (LCs) that does not meet criteria for DLBCL. Prior studies have noted this finding, but the clinical significance of these LCs has not been well established. A total of 161 cases of MZL from 1994 to 2021 were evaluated, including all subtypes. There were 33 cases with increased LCs (>10 LCs per high-power field [hpf]), with the majority containing >15 LCs/hpf (28/33) and 128 cases without increased LCs. Cases with increased LCs were significantly more likely to have a Ki-67 proliferation index of ≥30% (P < .0001). Overall survival was not significantly different between the groups but progression-free survival was significantly worse in the LC group (P < .0001). MZL with increased LCs was also associated with a higher stage at diagnosis (P = .0035), was more likely to transform to DLBCL (P = .0016), and had a greater frequency of relapse (P < .0001). Subgroup analysis showed that both nodal and MALT LC groups had a worse progression-free survival and a higher rate of relapse than their standard nodal and MALT lymphoma counterparts, but only within the MALT subgroup did the LC cases present at a higher stage and have a higher rate of transformation to DLBCL than the standard cases. Although larger studies are needed for validation, these results suggest that the presence of LCs in MZL may serve as a useful prognostic indicator and potentially help guide clinical decision-making.
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Linfoma de Zona Marginal Tipo Células B , Linfoma Difuso de Grandes Células B , Humanos , Linfoma de Zona Marginal Tipo Células B/patologia , Relevância Clínica , Recidiva Local de Neoplasia , Linfoma Difuso de Grandes Células B/patologia , RecidivaRESUMO
Aging is associated with immunological changes that compromise response to infections and vaccines, exacerbate inflammatory diseases and can potentially mitigate tissue repair. Even so, age-related changes to the immune response to tissue damage and regenerative medicine therapies remain unknown. Here, it is characterized how aging induces changes in immunological signatures that inhibit tissue repair and therapeutic response to a clinical regenerative biological scaffold derived from extracellular matrix. Signatures of inflammation and interleukin (IL)-17 signaling increased with injury and treatment both locally and regionally in aged animals, and computational analysis uncovered age-associated senescent-T cell communication that promotes type 3 immunity in T cells. Local inhibition of type 3 immune activation using IL17-neutralizing antibodies improves healing and restores therapeutic response to the regenerative biomaterial, promoting muscle repair in older animals. These results provide insights into tissue immune dysregulation that occurs with aging that can be targeted to rejuvenate repair.
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Calreticulina/genética , Análise Mutacional de DNA/métodos , Mutação de Sentido Incorreto , Mielofibrose Primária/genética , Receptores de Trombopoetina/genética , Alelos , Biópsia , Medula Óssea/patologia , Erros de Diagnóstico , Progressão da Doença , Reações Falso-Negativas , Feminino , Mutação da Fase de Leitura , Humanos , Limite de Detecção , Pessoa de Meia-Idade , Mielofibrose Primária/diagnóstico , Análise de Sequência de DNA , Trombocitemia Essencial/diagnósticoRESUMO
Monoclonal B-cell lymphocytosis is a clonal B-cell population in the peripheral blood (PB) of <5x10Ë9/L without extramedullary (EM) disease, often with a chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) phenotype. The degree of bone marrow (BM) involvement is not currently a part of the diagnostic criteria for MBL or CLL/SLL, but CLL-type MBLs in BM can be seen in patients lacking PB lymphocytosis. Data are limited on the outcome of such cases. We assessed the clinicopathologic characteristics of isolated BM CLL-type MBL in patients who did not meet criteria for CLL/SLL. We evaluated BMs from 2006 to 2018 with CLL-like clonal B-cell populations in patients with a PB absolute lymphocyte count or monoclonal B-cell count of <5 × 109/L and without definite evidence of EM disease. We investigated the extent and pattern of marrow involvement, PB counts, flow cytometric data, genetics, concurrent hematopoietic diseases, and outcomes including progression and treatment. Thirty cases with BM MBL but <5x10E9/L PB monoclonal B cells and no EM disease were identified. Thirteen of 30 had additional hematopoietic neoplasms. The mean patient age was 74.1 years (median: 77 years, range: 43-91 years). No patients had lymphadenopathy (LAD) or splenomegaly by physical examination. By imaging, nine of 18 had LAD (8/9 < 1.5 cm) and four of 18 had splenomegaly but with other attributable etiologies. Mean PB absolute lymphocyte count (ALC) was 1.8×10E9/L (range: 0.5-5.0×10E9/L). Twenty-four of 30 (80%) had low-level (<20%) BM involvement by MBL, and among these, none with available follow-up data progressed to diagnostic CLL/SLL. Six of 30 (20%) had >20% marrow involvement by MBL. Four of 6 were treated for CLL/SLL due to cytopenias, despite not meeting diagnostic criteria, and all 4 were CD38 or ZAP70 positive and had cytogenetic abnormalities, including trisomy 12. One of 6 developed overt CLL/SLL 3 years later and had cytogenetic abnormalities at the time of MBL diagnosis. One of 6 was monitored without treatment but had no cytogenetic abnormalities.Isolated BM CLL-type MBL represents a diagnostic gray area, and this study highlights the range of clinical outcomes. All cases with <20% BM involvement did not require CLL-specific treatment or progress to CLL/SLL. In the 4 cases where treatment was initiated due to cytopenias, patients had ≥20% BM involvement, CD38 or ZAP70 expression, and cytogenetic abnormalities but lacked a PB ALC of ≥5x10E9/L or LAD ≥1.5 cm, suggesting that not all patients with clinically significant disease will meet criteria for CLL/SLL. The results also show that concurrent hematopoietic disorders can complicate the diagnosis, as the disease course or treatment may result in leukopenia, precluding PB absolute lymphocytosis. Though larger studies are needed, the degree of BM involvement, in conjunction with flow cytometric prognostic markers, and cytogenetic abnormalities may be a useful addition to the current diagnostic criteria for CLL/SLL which only considers a PB numerical cutoff and EM involvement.
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Leucemia Linfocítica Crônica de Células B , Linfocitose , Linfoma de Células B , Neoplasias de Plasmócitos , Lesões Pré-Cancerosas , Medula Óssea/patologia , Aberrações Cromossômicas , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Linfocitose/diagnóstico , Linfocitose/patologia , Linfoma de Células B/patologia , EsplenomegaliaRESUMO
In the current World Health Organization classification, terminal deoxynucleotidyl transferase (TdT) expression in a high grade/large cell B-cell lymphoma (LBCL) indicates a B-lymphoblastic lymphoma/leukemia (B-LBL), although TdT expression in what appear to be mature LBCL or following mature B-cell neoplasms is reported. The frequency of TdT+ LBCL, how to best categorize these cases, and their clinicopathologic features, molecular landscape, and relationship to classic B-LBL remain to be better defined. TdT expression was therefore assessed in 258 LBCL and the results correlated with the cytologic, phenotypic, and cytogenetic findings. Targeted mutational analysis, review of prior biopsies, and assessment of clinical associations was performed in the 6 cases with >10% TdT+ cells. All 6 TdT+ LBCL were blastoid-appearing, CD34-, MYC+, BCL2+, and had MYC rearrangements (R) (5/6 with BCL2 and/or BCL6-R). 5/6 had a prior TdT- LBCL and/or follicular lymphoma and all had an aggressive course. Fifteen nonsynonymous variants in 11 genes were seen in the 4/5 tested cases with mutations. TdT+ and TdT- areas in 1 case showed identical mutations. The mutational profiles were more like those reported in germinal center B-cell type-diffuse LBCL rather than B-LBL. Evolution from preceding TdT- lymphomas was nondivergent in 1/3 tested cases and partially divergent in 2. The clinicopathologic and cytogenetic features of these 6 cases were similar to those found in a meta-analysis that included additional cases of TdT+ LBCL or B-LBL following follicular lymphoma. Thus, TdT+, CD34- large B-cell neoplasms with MYC rearrangements and often a "double hit" are rare, frequently a transformational event and aggressive but are distinct from classic B-LBL.
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Biomarcadores Tumorais/genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , DNA Nucleotidilexotransferase/genética , Feminino , Rearranjo Gênico , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hibridização in Situ Fluorescente , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Fenótipo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-myc/genética , Adulto JovemRESUMO
OBJECTIVES: Myelodysplastic/myeloproliferative neoplasms (MDS/MPN) are a group of rare and heterogeneous hematopoietic disorders that frequently present a diagnostic challenge. Here we present our institutional experience with next-generation sequencing (NGS), together with morphologic, flow cytometric, and cytogenetic evaluation, in the diagnosis of MDS/MPN, with particular emphasis on MDS/MPN unclassifiable (MPN-U). METHODS: We evaluated the morphologic, flow cytometric, cytogenetic, and molecular characteristics of all MDS/MPN cases that underwent NGS at our institution between April 2016 and February 2019. RESULTS: Thirty-seven cases of MDS/MPN were identified, including 14 cases of MDS/MPN-U. Ninety-seven percent harbored mutations and immunophenotypic aberrancies (36/37), while only 38% had cytogenetic abnormalities (12/32). The MDS/MPN-U group had the highest rate of myeloblast phenotypic abnormalities and had a high mutation rate of approximately 2.7 mutated genes per case, most commonly in JAK2, SRSF2, and ASXL1. CONCLUSIONS: No single ancillary study was abnormal in every case, but all cases had at least one abnormal finding, demonstrating the usefulness of a multiparameter approach to the diagnosis of MDS/MPN. Although a few specific mutations were found exclusively in MDS/MPN-U and JAK2 mutations were most prevalent, larger studies are needed to determine whether MDS/MPN-U has a mutational "fingerprint," which may aid in diagnosis and targeted therapy.
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Doenças Mieloproliferativas-Mielodisplásicas/diagnóstico , Transtornos Mieloproliferativos/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Citogenética , Feminino , Citometria de Fluxo , Células Precursoras de Granulócitos/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Doenças Mieloproliferativas-Mielodisplásicas/classificação , Doenças Mieloproliferativas-Mielodisplásicas/genética , Doenças Mieloproliferativas-Mielodisplásicas/patologia , Transtornos Mieloproliferativos/classificação , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Análise de Sequência de DNA , Adulto JovemRESUMO
OBJECTIVES: Follicular hyperplasias (FHs) with light chain-restricted (LCR) plasmacytoid/plasma cells (PCs) within germinal centers (GCs) based on immunohistochemistry (IHC)/in situ hybridization (ISH) can potentially lead to diagnostic error. This study aims to better characterize such cases, including their clinical implications. METHODS: LC expression by IHC/ISH was quantitatively assessed in GCs of 17 FHs with LCRGCs. BCL2, CD10, BCL6, BCL2, immunoglobulin (Ig) heavy chains, IgG4, and Epstein-Barr encoding region stains were performed. In total, 8 cases had polymerase chain reaction (PCR)-based clonality studies. RESULTS: All cases showed FH, including 4 with progressively transformed GCs (PTGCs); 0.8% to 52% (median, 21%) of the GCs were LCR; 13 of 17 had both κ- and λ-LCRGCs, and 4 of 17 had only κ-LCRGCs; 7 of 16 had prominent intrafollicular IgG4-positive cells. One case demonstrated BCL2-positive cells in focal LCRGCs but lacked BCL2 rearrangement. B-cell monoclonality was demonstrated in 3 of 8 cases (only after microdissection). Seven patients had autoimmune disorders, and 1 had had a transplant. Three patients had a history of lymphoma, 1 developed lymphoma, and 1 developed lymphomatoid granulomatosis subsequently. CONCLUSIONS: FHs with LCRGC by IHC/ISH are typically not associated with the development of lymphoma, even though they can express BCL2 and show monoclonality by PCR. They may be associated with increased intrafollicular IgG4-positive cells, PTGC, and autoimmunity.
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Centro Germinativo/imunologia , Centro Germinativo/patologia , Cadeias Leves de Imunoglobulina/imunologia , Plasmócitos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia/imunologia , Hiperplasia/patologia , Linfoma/diagnóstico , Linfoma/imunologia , Linfoma/patologia , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/patologia , Masculino , Pessoa de Meia-Idade , Plasmócitos/patologia , Estudos RetrospectivosRESUMO
The immune system plays a critical role in directing tissue repair and regeneration outcomes. Tissue engineering technologies that are designed to promote new tissue growth will therefore be impacted by immune factors that are present in patients both locally at the site of intervention and systemically. The immune state of patients can be influenced by many factors, including infection, nutrition, and other disease comorbidities. As a result, the immune state is highly variable and may be a source of variability in tissue-engineered products in the clinic, which is not found in preclinical models. In this review, we will summarize key immune cells and evidence of their activity in tissue repair and potential in tissue engineering systems. We also discuss how clinical translation of tissue engineering strategies, in particular stem cells, helped elucidate the importance of the immune system. With increased understanding of the immune system's role in repair and tissue engineering systems, it will likely become a therapeutic target and component of future therapies.
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Medicina Regenerativa , Engenharia Tecidual , Humanos , Sistema Imunitário , Células-TroncoRESUMO
OBJECTIVES: We investigated the usefulness of a custom-designed 31-gene next-generation sequencing (NGS) panel implemented on a routine basis for the evaluation of low-grade lymphoproliferative disorders (LPDs). METHODS: In total, 147 blood, bone marrow, and tissue specimens were sequenced, including 81% B-cell, 15% T-cell, and 3% natural killer (NK)-cell neoplasms. RESULTS: Of the cases, 92 (63%) of 147 displayed at least one pathogenic variant while 41 (28%) of 147 had two or more. Low mutation rates were noted in monoclonal B-cell lymphocytoses and samples with small T- and NK-cell clones of uncertain significance. Pathogenic molecular variants were described in specific disorders and classified according to their diagnostic, prognostic, and potential therapeutic value. Diagnostically, in addition to confirming the diagnosis of 15 of 15 lymphoplasmacytic lymphomas, 10 of 12 T large granular lymphocytic leukemias, and 2 of 2 hairy cell leukemias (HCLs), the panel helped resolve the diagnosis of 10 (62.5%) of 16 challenging cases lacking a specified diagnosis based on standard morphology, phenotype, and genetic analysis. CONCLUSIONS: Overall, implementation of this targeted lymphoid NGS panel as part of regular hematopathology practice was found to be a beneficial adjunct in the evaluation of low-grade LPDs.
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Leucemia de Células Pilosas/diagnóstico , Leucemia Linfocítica Granular Grande/diagnóstico , Linfoma de Células B/diagnóstico , Transtornos Linfoproliferativos/diagnóstico , Macroglobulinemia de Waldenstrom/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/patologia , Medula Óssea/patologia , Feminino , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células Matadoras Naturais/patologia , Leucemia de Células Pilosas/patologia , Leucemia Linfocítica Granular Grande/patologia , Linfoma de Células B/patologia , Transtornos Linfoproliferativos/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Análise de Sequência de DNA , Macroglobulinemia de Waldenstrom/patologiaRESUMO
B cells are an adaptive immune target of biomaterials development in vaccine research but, despite their role in wound healing, have not been extensively studied in regenerative medicine. To probe the role of B cells in biomaterial scaffold response, we evaluated the B cell response to biomaterial materials implanted in a muscle wound using a biological extracellular matrix (ECM), as a reference for a naturally derived material, and synthetic polyester polycaprolactone (PCL), as a reference for a synthetic material. In the local muscle tissue, small numbers of B cells are present in response to tissue injury and biomaterial implantation. The ECM materials induced mature B cells in lymph nodes and antigen presentation in the spleen. The synthetic PCL implants resulted in prolonged B cell presence in the wound and induced an antigen-presenting phenotype. In summary, the adaptive B cell immune response to biomaterial induces local, regional, and systemic immunological changes.
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In this review, we explore the roles of macrophages both in vessel development and in vascularization of tissue engineered constructs. Upon the implantation of tissue engineered constructs into the body, macrophages respond, invade and orchestrate the host's immune response. By altering their phenotype, macrophages can adopt a variety of roles. They can promote inflammation at the site of the implanted construct; they can also promote tissue repair. Macrophages support tissue repair by promoting angiogenesis through the secretion of pro-angiogenic cytokines and by behaving as support cells for nascent vasculature. Thus, the ability to manipulate the macrophage phenotype may yield macrophages capable of supporting vessel development. Moreover, macrophages are an easily isolated autologous cell source. For the generation of vascularized constructs outside of the body, these isolated macrophages can also be skewed to adopt a pro-angiogenic phenotype and enhance blood vessel development in the presence of endothelial cells. To assess the influence of macrophages on vessel development, both in vivo and in vitro models have been developed. Additionally, several groups have demonstrated the pro-angiogenic roles of macrophages in vascularization of tissue engineered constructs through the manipulation of macrophage phenotypes. This review comments on the roles of macrophages in promoting vascularization within these contexts.
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Células Endoteliais/metabolismo , Macrófagos/metabolismo , Modelos Cardiovasculares , Neovascularização Fisiológica , Engenharia Tecidual/métodos , Animais , Células Endoteliais/citologia , Humanos , Macrófagos/citologiaRESUMO
Myocyte enhancer binding factor 2B (MEF2B) is a transcriptional activator of the BCL6 proto-oncogene in normal germinal center (GC) B-cells. Limited data exists concerning its expression in B-cell lymphomas, and comparison with other GC-associated antigens is lacking. Its role in the differential diagnosis of B-cell lymphomas, particularly in the distinction of follicular lymphoma (FL) versus marginal zone lymphoma (MZL), remains to be determined. We evaluated MEF2B expression, in comparison with additional GC markers, LIM domain-only transcription factor 2 (LMO2), and human GC-associated lymphoma (HGAL), in a variety of B-cell lymphomas, with particular emphasis on their utility in differentiating FL from MZL. MEF2B was positive in all FL and Burkitt lymphomas, 8/9 mantle cell lymphomas, 2/24 splenic MZL, 1/10 chronic lymphocytic leukemia/small lymphocytic lymphomas, and 38/44 diffuse large B-cell lymphoma (DLBCL), but was negative in all extranodal MZL of mucosa-associated lymphoid tissue, nodal MZL, and B-lymphoblastic lymphomas. Focusing on low-grade FL versus MZL, MEF2B was 100% sensitive and 95% specific for FL, which was similar to BCL6, but superior to LMO2 (sensitivity 87%, specificity 86%) and HGAL (sensitivity 97%, specificity 86%). Importantly, MEF2B was positive in 4/4 FL with plasmacytoid differentiation, which were CD10, only weakly BCL6, and included 1 case that lacked both LMO2 and HGAL expression. MEF2B was positive in 22/25 (88%) GC-type DLBCL, but was also positive in 16/19 (61%) non-GC-type DLBCL. MEF2B shows superior sensitivity and specificity than LMO2 and HGAL in the differential diagnosis of FL versus MZL and is particularly useful in FL with plasmacytoid differentiation, which may have morphologic and immunophenotypic overlap with MZL. MEF2B, however, is not specific for GC-derived B-cell lymphomas as it is also apparently positive in most mantle cell lymphoma and many non-GC-type DLBCL.
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Proteínas Adaptadoras de Transdução de Sinal/análise , Biomarcadores Tumorais/análise , Centro Germinativo/imunologia , Proteínas com Domínio LIM/análise , Linfoma de Células B/imunologia , Proteínas de Neoplasias/análise , Proteínas Proto-Oncogênicas/análise , Diferenciação Celular , Diagnóstico Diferencial , Centro Germinativo/patologia , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular , Linfoma de Células B/classificação , Linfoma de Células B/patologia , Linfoma de Zona Marginal Tipo Células B/imunologia , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma Folicular/imunologia , Linfoma Folicular/patologia , Fatores de Transcrição MEF2/análise , Proteínas dos Microfilamentos , Neprilisina/análise , Valor Preditivo dos Testes , Proto-Oncogene Mas , Análise Serial de TecidosRESUMO
Although most classical Hodgkin lymphomas (CHLs) are easily distinguished from nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) and primary mediastinal large B-cell lymphoma (PMBL), cases with significant CD20 expression cause diagnostic confusion. Although the absence of OCT-2 and BOB.1 are useful in these circumstances, a variable proportion of CHLs are positive for these antigens. We investigated the utility of J chain and myocyte enhancer factor 2B (MEF2B) in the diagnosis of CHL; NLPHL; PMBL; T-cell/histiocyte-rich large B-cell lymphoma (TCRLBL); and B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and CHL, compared with OCT-2 and BOB.1. J chain and MEF2B highlighted lymphocyte predominant (LP) cells in 20/20 (100%) NLPHLs and were negative in 43/43 (100%) CHLs. Fourteen of 15 (93%) PMBLs and 4/4 (100%) TCRLBLs were MEF2B positive, whereas 67% of PMBLs and 50% of TCRLBLs were J chain positive. Three of 3 B-cell lymphomas, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and CHL, were negative for J chain and MEF2B. J chain and MEF2B were 100% sensitive and specific for NLPHL versus CHL. MEF2B was 100% sensitive and 98% specific for PMBL versus CHL. Whereas loss of OCT-2 and/or BOB.1 expression had a sensitivity of only 86% and specificity of 100% for CHL versus NLPHL, PMBL, and TCRLBL, lack of both J chain and MEF2B expression was 100% sensitive and 97% specific. J chain and MEF2B are highly sensitive and specific markers of NLPHL versus CHL; are particularly useful in highlighting LP cells; and, with rare exception, are of greater utility than OCT-2 and BOB.1 in differentiating CHL from NLPHL and other large B-cell lymphomas.
Assuntos
Biomarcadores Tumorais/análise , Doença de Hodgkin/metabolismo , Cadeias J de Imunoglobulina/análise , Linfoma de Células B/química , Linfoma Folicular/química , Neoplasias do Mediastino/química , Diagnóstico Diferencial , Doença de Hodgkin/patologia , Humanos , Imuno-Histoquímica , Linfoma de Células B/patologia , Linfoma Folicular/patologia , Fatores de Transcrição MEF2/análise , Neoplasias do Mediastino/patologia , Fator 2 de Transcrição de Octâmero/análise , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Transativadores/análiseRESUMO
The 2016 World Health Organization classification recognized "high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements" (double/triple-hit lymphoma [DTHL]) and "high-grade B-cell lymphoma, not otherwise specified," which includes non-DTHL with a "blastoid" or "intermediate" cytology. Although extensively studied, many questions remain, including which cases belong in these categories, which factors mitigate their adverse prognosis, and when to perform fluorescence in situ hybridization studies. Therefore, the clinicopathologic features of 187 large B-cell lymphomas with MYC, BCL2, and BCL6 fluorescence in situ hybridization were investigated. There were 47 DTHLs, 36 cases with MYC and BCL2 and/or BCL6 extra signals (ES) and/or rearrangements (ES group, excludes DTHLs), 9 with MYC rearrangements only (single-hit lymphoma), and 95 with no MYC abnormalities (NM). Patients with DTHLs, but not single-hit lymphomas, had a significantly worse prognosis compared with those with NM (P=0.0079). The ES group with at least 1 rearrangement had a worse prognosis compared with the NM/ES without rearrangement group (P<0.02). Blastoid, but not intermediate cases, were enriched in DTHLs (P<0.0001) and had a significantly worse prognosis even among DTHLs (P=0.0282). The prognosis of the diffuse large B-cell lymphoma and intermediate groups was similar. International Prognostic Index score was of prognostic importance for the entire group and for DTHLs (P=0.0074). About 93% of DTHLs were of GCB type but 24% had <40% MYC+ cells. Among the DTHLs, MYC+BCL2+ double expressor cases had a worse prognosis (P=0.0328). These results highlight the importance of morphologic, phenotypic, and clinical variations among the DTHLs and suggest that a diagnosis equivalent to DTHL should not be made based solely on ES for MYC and BCL2 and/or BCL6.