Publications by authors named "Laurence De Leval"

Lymphomas of T-follicular helper origin (T-follicular helper-cell lymphoma [TFHL]) are often accompanied by an expansion of B-immunoblasts, occasionally with Hodgkin/Reed-Sternberg-like (HRS-like) cells, making the differential diagnosis with classic Hodgkin lymphoma (CHL) difficult. We compared the morphologic, immunophenotypic, and molecular features of 15 TFHL and 12 CHL samples and discussed 4 challenging cases of uncertain diagnosis. Compared with CHL, TFHL disclosed more frequent sparing of subcortical sinuses, high-endothelium venule proliferation, dendritic cell meshwork expansion, T-cell atypia, and aberrant T-cell immunophenotype.

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The analysis of circulating tumor DNA (ctDNA) in liquid biopsy specimens has an established role for the detection of predictive molecular alterations and acquired resistance mutations in several tumors. The low-invasiveness of this approach allows for repeated sampling and dynamic monitoring of disease evolution. Originating from the entire body tumor bulk, plasma-derived ctDNA reflects intra- and interlesional genetic heterogeneity.

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Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related neoplasm preferentially involving the upper aerodigestive tract. Here we show that NK-cell-specific Trp53 disruption in mice leads to the development of NK-cell lymphomas after long latency, which involve not only the hematopoietic system but also the salivary glands. Before tumor onset, Trp53 knockout causes extensive gene expression changes, resulting in immature NK-cell expansion, exclusively in the salivary glands.

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Article Synopsis
  • Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a diverse and challenging type of cancer that often has poor outcomes, especially in younger patients lacking the SMARCB1 protein.
  • Research indicated that human and mouse PTCL-NOS exhibit similar DNA changes, including the hypermethylation of T-cell genes and the hypomethylation of myeloid development genes, contributing to a complicated tumor ecosystem.
  • A study found that histone deacetylase inhibitors (HDACi), like SAHA, can effectively treat PTCL-NOS by modifying the tumor's microenvironment and improving immune function, paving the way for potential combination therapies.
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Mantle cell lymphoma (MCL) is genetically characterized by the IG::CCND1 translocation mediated by an aberrant V(D)J rearrangement. CCND1 translocations and overexpression have been identified in occasional aggressive B-cell lymphomas with unusual features for MCL. The mechanism generating CCND1 rearrangements in these tumors and their genomic profile are not known.

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JCO Primary analysis of the phase III randomized AATT study showed that younger patients with peripheral T-cell lymphoma (PTCL) consolidated with autologous or allogeneic transplantation (alloSCT) had similar event-free survival (EFS) and overall survival (OS). Seven-year EFS of patients randomly assigned to alloSCT was 38% (95% CI, 25 to 52) compared with 34% (95% CI, 22 to 47) for patients randomly assigned to autologous transplantation of hematopoietic stem cells (autoSCT); OS was 55% (95% CI, 41 to 69) and 61% (95% CI, 47 to 74). Among patients undergoing alloSCT (n = 26) or autoSCT (n = 41) on study, the cumulative progression/relapse rate was 8% (95% CI, 0 to 19) and 55% (95% CI, 35 to 74).

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A subset of people living with HIV (PLWH) can produce broadly neutralizing antibodies (bNAbs) against HIV, but the lymph node (LN) dynamics that promote the generation of these antibodies are poorly understood. Here, we explored LN-associated histological, immunological, and virological mechanisms of bNAb generation in a cohort of anti-retroviral therapy (ART)-naïve PLWH. We found that participants who produce bNAbs, termed neutralizers, have a superior LN-associated B cell follicle architecture compared with PLWH who do not.

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The impact of HIV infection on the tumor microenvironment (TME) of classic Hodgkin lymphoma (cHL), one of the most common comorbidities after HIV infection, is not well understood. Here, we have used multiplexed immunofluorescence and spatial transcriptomic analysis to dissect the impact of viral infections (Epstein-Barr virus [EBV] and HIV/EBV) on cHL TME. HIV-EBV+ cHL TME was characterized by higher cell densities of CD8high T cells coexpressing inhibitory receptors (PD-1 and TIGIT), macrophage subsets, and an in situ inflammatory molecular profile associated with increased expression of T-cell receptor (TCR) and B-cell receptor cell signaling pathways than HIV-EBV- cHL TME.

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Article Synopsis
  • Diagnosis of primary diffuse large B-cell lymphoma of the central nervous system (PCNSL) is often difficult and delayed due to low sensitivity of standard tests like MRI, CSF cytology, and even brain biopsies.
  • In three reported cases, novel CSF biomarkers, including the MYD88 L265P mutation and specific cytokine levels, helped suggest the diagnosis of PCNSL, which was later confirmed by biopsy or autopsy.
  • The study highlights five key CSF biomarkers (IL-10, IL-10/IL-6 ratio, CXCL13, MYD88 mutation, and monoclonal immunoglobulin rearrangements) that can improve diagnostic accuracy for PCNSL.
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Adjuvant immunotherapy has been recently recommended for patients with metastatic clear cell renal cell carcinoma (ccRCC), but there are no tissue biomarkers to predict treatment response in ccRCC. Potential predictive biomarkers are mainly assessed in primary tumor tissue, whereas metastases (METs) remain understudied. To explore potential differences between genomic alterations and immune phenotypes in primary tumors and their matched METs, we analyzed primary tumors (PTs) of 47 ccRCC patients and their matched distant METs by comprehensive targeted parallel sequencing, whole-genome copy number variation analysis, determination of microsatellite instability, and tumor mutational burden.

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Aplastic anemia is a rare disease with a large differential diagnosis, including neoplastic origin as well as congenital bone marrow failure syndromes. Investigations must be quick and precise. Treatment depends on the patient's age and consists of immunosuppression treatment or allogeneic bone marrow transplantation.

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Article Synopsis
  • Immunotherapies have shown limited success in treating nodal peripheral T-cell lymphomas (PTCLs) due to a poor understanding of their immune responses.
  • Researchers conducted detailed analyses of the immune tumor microenvironment (TME) in various PTCL samples, revealing a higher presence of regulatory T cells and exhausted CD8+ T cells.
  • The study found that high levels of CD39 expression on T cells are associated with worse patient outcomes, suggesting it as a potential new prognostic factor and target for treatment.
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  • Follicular helper T-cell lymphomas (TFHL) often have gene alterations affecting DNA methylation, and preliminary studies indicate that 5-azacitidine may be effective for patients with relapsed TFHL.
  • This study compared the oral azacitidine treatment to typical therapies (like gemcitabine and bendamustine) in patients over 18 with relapsed or refractory TFHL across five European countries and Japan.
  • The trial enrolled 86 patients, showing that those treated with azacitidine had a median progression-free survival of 5.6 months, significantly longer compared to 2.8 months for those receiving standard therapy.
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  • Adult hematopoietic stem and progenitor cells (HSPCs) usually reside in the bone marrow, where the microenvironment regulates their activity, but simpler extramedullary niches also exist.
  • The study suggests that the adult adrenal gland can be manipulated into a supportive environment for HSPCs through splenectomy and hormonal stimulation, leading to new stromal formations capable of hosting these stem cells.
  • Created niches in the adrenal gland utilize the CXCR4-CXCL12 signaling pathway for HSPC homing, and similar cells were found in human adrenal tumors, indicating potential for further research and therapeutic strategies in hematopoiesis.
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T- and natural killer (NK)-cell lymphomas are neoplasms derived from immature T cells (lymphoblastic lymphomas), or more commonly, from mature T and NK cells (peripheral T-cell lymphomas, PTCLs). PTCLs are rare but show marked biological and clinical diversity. They are usually aggressive and may present in lymph nodes, blood, bone marrow, or other organs.

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Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related neoplasm with male dominance and a poor prognosis. A better understanding of the genetic alterations and their functional roles in ENKTCL could help improve patient stratification and treatments. In this study, we performed a comprehensive genetic analysis of 178 ENKTCL cases to delineate the landscape of mutations, copy number alterations (CNA), and structural variations, identifying 34 driver genes including six previously unappreciated ones, namely, HLA-B, HLA-C, ROBO1, CD58, POT1, and MAP2K1.

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Article Synopsis
  • PD1 is a protein on T cells that helps prevent them from attacking cancer, but not all patients benefit from treatments targeting it.
  • Scientists studied how PD1 impacts certain proteins in T cells and found it stops a key protein called PKCθ from working properly.
  • This blockage may cause smaller immune attacks on cancer, so measuring changes in a related protein, vimentin, could help doctors understand how well the treatment is working.
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JCO The primary analysis of the Ro-CHOP phase III randomized controlled trial (ClinicalTrials.gov identifier: NCT01796002) established that romidepsin (Ro) plus cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) did not yield an increased efficacy compared with CHOP alone as first-line treatment of peripheral T-cell lymphoma. We report the planned final analysis 5 years after the last patient enrolled.

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Primary bone lymphoma (PBL) is rare and mostly represented by diffuse large B-cell lymphomas (DLBCL). Follicular lymphoma (FL), albeit commonly disseminating to the bone marrow, rarely presents primarily as bone lesions. Here, we studied 16 patients (12 men:4 women, median age 60 years) who presented with bone pain and/or skeletal radiologic abnormalities revealing bone FL.

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In this review focus article, we highlight the main modifications introduced in the latest 2022 International Consensus Classification and World Health Organization classification (ICC and WHO-HAEM5) of mature T (and NK) cell neoplasms (PTCLs) and consequent implications for diagnostic practice. The changes result from recent advances in the genomic and molecular characterization of PTCLs and enhanced understanding of their pathobiology. Specifically, consideration is given to the following groups of diseases: Epstein-Barr virus (EBV)-associated neoplasms; follicular helper T cell lymphoma; anaplastic large cell lymphomas; primary intestinal T and NK cell lymphomas and lymphoproliferative disorders; and PTCL, not otherwise specified.

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Predominantly nodal is the most common clinical presentation of peripheral T- (and NK-) cell lymphomas (PTCL), which comprise three main groups of diseases: (i) systemic anaplastic large cell lymphomas (ALCL), whether positive or negative for anaplastic lymphoma kinase (ALK); (ii) follicular helper T-cell lymphomas (TFHL); and (iii) PTCL, not otherwise specified (NOS). Recent advances in the genomic and molecular characterization of PTCL, with enhanced understanding of pathobiology, have translated into significant updates in the latest 2022 classifications of lymphomas. ALK-negative ALCL is now recognized to be genetically heterogeneous, with identification of DUSP22 rearrangements in approximately 20-30% of cases, correlated with distinctive pathological and biological features.

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Aims: Follicular helper T-cell (TFH) lymphoma of the angioimmunoblastic-type (AITL), one of the most prevalent T-cell lymphomas, typically encompasses proliferation of high endothelial venules and Epstein-Barr virus-positive immunoblasts, but neither infection with HHV8 nor association with Kaposi's sarcoma (KS) have been described. The aims of this study are to characterise the association between AITL and HHV8 infection or KS.

Methods And Results: Three male patients aged 49-76 years, HIV-negative, with concurrent nodal involvement by AITL and KS, were identified from our files and carefully studied.

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