Search Results (45)

Diffuse large B-cell lymphoma (DLBCL), recognized as the most prevalent variant of adult non-Hodgkin lymphoma, presents considerable challenges in diagnosis owing to its diverse morphological features and frequent extranodal involvement, which may frequently mimic nonhematopoietic neoplasms. The 2022 WHO Classification of Lymphoid and Hematopoietic Tissues provides essential updates, highlighting the necessity of combining morphology, immunohistochemistry, cytogenetics, and molecular testing for precise subclassification. This review presents a practical method for differentiating DLBCL from other aggressive B-cell neoplasms, such as Burkitt lymphoma, B-lymphoblastic lymphoma, and mantle cell lymphoma. It highlights vital diagnostic tools, including CD45, B/T-cell markers, germinal center markers, and the Hans algorithm, as well as the role of FISH in identifying rearrangements of key genes MYC, BCL2, and BCL6, which are significant for recognizing double-hit and triple-hit lymphomas. Special focus is given to EBV-associated DLBCL and uncommon subtypes featuring plasmablastic or ALK-positive traits. This review aims to enhance diagnostic accuracy and ensure appropriate treatment strategies for patients with large B-cell lymphomas by emphasizing thorough morphological evaluation, specific adjunct testing, and adherence to the most recent classification standards. Full article

High-grade B-cell lymphoma (HGBL), not otherwise specified (NOS), is a rare entity within the spectrum of B-cell lymphomas. HGBL, NOS remains a diagnosis of exclusion with limited data available on the optimal clinical approach. We report a case of a 67-year-old man with HGBL, NOS with a germinal center B-cell (GCB) immunophenotype. The disease was characterized by an aggressive clinical course, refractory to multiple lines of cytotoxic chemotherapy, immunotargeted treatment, therapy with a PD-1 inhibitor, and haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Ultimately, the disease progression led to the patient’s death nine months post-diagnosis. A FISH assay identified a sole genetic rearrangement: BCL2/IGH. Whole-exome sequencing revealed a number of significant somatic mutations, such as TP53 p.C238G, B2M p.L12R, STAT6 p.D419G, STAT3 p.S614R, TREX1 p.T49fs, and CREBBP p.C367Ter, as well as a high focal amplification of the MUC3A gene and the deletion of the short arm of chromosome 17 (del(17p)). An inactivating somatic mutation in the TREX1 gene (p.T49fs) has not been previously described in patients with non-Hodgkin lymphomas. Additionally, our analysis uncovered a key cancer hallmark: tumor genomic instability, manifested as a high tumor mutational burden, which likely contributed to the aggressive disease course. Full article

BCL2 is a critical regulator of intrinsic and extrinsic pathways of apoptosis that have been implicated in cancer progression and therapeutic resistance. In this study, the protein–protein interactions (PPIs) of BCL2 with potential binding partners and their role in cancer was investigated. A comprehensive PPI network for BCL2 has been generated by using the Protein Interactions Network Analysis (PINA) platform to identify key interactors. To further investigate the network, Molecular Operating Environment (MOE), Search Tool for the Retrieval of Interacting Genes (STRING), Residue Interaction Network Generation (RING), and the gProfiler server were used. Docking and Molecular Dynamics (MD) simulations were performed by using HDOCK and Gromacs to analyze the binding dynamics and stability of protein complexes. The BCL2 interactome revealed that three key interactors (p53, RAF1, and MAPK1) are involved in cancer-related processes. Docking studies highlighted BCL2 residues such as ASP111, ASP140, ARG107, and ARG146 that were predominantly involved in multiple hydrogen bonds, ionic interactions, and van der Waals contacts, highlighting conserved binding sites that play critical roles in the stability and specificity of protein–protein interactions. MD simulations (200 ns) of the BCL2-p53 complex showed that the RMSD was increased, suggesting the suppression of BCL2’s anti-apoptotic activity by p53. The RMSD for BCL2-RAF1 was also increased, showing protein domain structural rearrangements that enhance BCL2 anti-apoptotic activity. The BCL2-MAPK1 complex revealed structural, distinct flexibility patterns and dynamic hydrogen bonding interactions. These findings provide valuable insights into the molecular dynamics by which BCL2 modulates apoptosis and its potential as a promising therapeutic in cancer and apoptosis-related diseases. Full article

Rare diseases (RDs) often have a genetic basis, yet conventional diagnostic techniques fail to identify causative genetic variations in up to 50% of cases. Structural variants (SVs), including balanced rearrangements, frequently evade detection by karyotyping, microarray, and exome sequencing. The present study utilized optical genome mapping (OGM) to investigate two patients with RDs whose genetic etiology remained unresolved despite prior genomic analyses. Patient 1 exhibited a balanced reciprocal translocation disrupting the BCL11A gene, associated with Dias-Logan syndrome. Patient 2 had a mosaic 682 kb deletion near the IHH gene, causing ectopic enhancer–promoter interactions and polydactyly, mirroring phenotypes observed in mouse models and similar human cases. These findings highlight OGM’s efficacy in identifying complex SVs and underline novel pathogenic mechanisms in rare genetic disorders. Consequently, the incorporation of OGM into routine diagnostic procedures will enhance genetic diagnosis, discover new syndromes of currently unknown cause, and eventually improve the clinical management of numerous patients with rare diseases. Full article

In this article, we provide a review of large B-cell lymphomas (LBCLs), comparing the recently published fifth edition of the WHO classification and the International Consensus Classification (ICC) on hematolymphoid tumors. We focus on updates in the classification of LBCL, an heterogeneous group of malignancies with varying clinical behaviors and different pathological and molecular features, providing a comparison between the two classifications. Besides the well-recognized diagnostic role of clinical, morphological and immunohistochemical data, both classifications recognize the ever-growing impact of molecular data in the diagnostic work-up of some entities. The main aim is to offer a guide for clinicians and pathologists on how the new classifications can be applied to LBCL diagnosis in routine practice. In the first part of the paper, we review the following categories: LBLs transformed from indolent B-cell lymphomas, diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS), double-hit/triple-hit lymphomas (DH/TH), high-grade large B-cell lymphoma, not otherwise specified (HGBCL, NOS), LBCL with IRF4 rearrangement, Burkitt lymphoma (BL) and HGBCL/LBCL with 11q aberration, focusing on the differences between the two classifications. In the second part of the paper, we provide a practical diagnostic algorithm when facing LBCLs in routine daily practice. Full article

Background: High-grade B-cell lymphoma with c-MYC and BCL2 and/or BCL6 rearrangements (HGBL-DHL/THL) is a recently identified category in the most recent World Health Organization (WHO) classification. For all tumors displaying the appearance of diffuse large B-cell lymphoma (DLBCL) or high-grade B-cell lymphoma (HGBL), it is necessary to perform fluorescence in situ hybridization (FISH) in order to achieve an accurate diagnosis. The findings of FISH and immunohistochemistry (IHC) examinations from 50 DLBCL/HGBL samples obtained from Hassan II University Hospital in Fez/Morocco are reported. Methods: This retrospective study included 50 patients diagnosed with DLBCL/HGBL over a period of nine years (2013–2022) and treated with RCHOP chemotherapy protocol. All patients underwent a histological study followed by an immunohistochemical study to confirm the diagnosis and to classify patients according to cell of origin into non-GCB and GCB subtypes; then, a cytogenetic study using FISH was performed to classify patients according to the presence or absence of rearrangements in the c-MYC, BCL2 and BCL6 genes. A comparison was made between the molecular subtypes of DLBCL/HGBL in relation to clinicopathological features and outcomes. Results: Among the 50 cases studied in our population, we found 5 cases of HGBL with DLBCL morphology and 45 cases of DLBCL, which consisted of 13 cases (28.89%) of GCB subtype and 32 cases (71.11%) of non-GCB subtype based on the immunohistochemistry Hans algorithm. After FISH testing of all cases, we found three cases of double-hit lymphoma (DHL) and one case of triple-hit lymphoma (THL). Thus, HGBL-DHL/THL accounted for 8% of the cases. Furthermore, two cases were detected with only one rearrangement in the BCL2 gene and one case harboring a rearrangement in the BCL6 gene. DHL and THL patients and patients with a single rearrangement (BCL2 or BCL6) have a worse prognosis than patients with no rearrangement. Conclusions: DHL and THL are an aggressive entity of HGBL with poorer outcomes in comparison to DLBCL/HGBL NOS. First-line treatment with the RCHOP chemotherapy protocol may not be effective for all aggressive DLBCL cases. More targeted treatment is crucial for better patient outcomes. Full article

Aggressive B-cell lymphoma encompasses Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), and, as per the 2016 WHO classification, high-grade B-cell lymphoma (HGBL) not otherwise specified (NOS) and HGBL double/triple hit (DH/TH). However, the diagnostic distinction of HGBL from BL and DLBCL is difficult by means of histology/immunostaining in a substantial number of patients. This study aimed to improve subtyping by the identification of molecular features of aggressive B-cell lymphomas, with a specific focus on HGBL. To this end, we performed a comprehensive gene expression and mutational pattern analysis as well as the detection of B-cell clonality of 34 cases diagnosed with BL (n = 4), DLBCL (n = 16), HGBL DH (n = 8), and HGBL NOS (n = 6). Three distinct molecular subgroups were identified based on gene expression, primarily influenced by MYC expression/translocation and cell proliferation. In HGBL, compared to BL, there was an upregulation of PRKAR2B and TERT. HGBL DH exhibited elevated expression of GAMT and SMIM14, while HGBL NOS showed increased expression of MIR155HG and LZTS1. Our gene mutation analysis revealed MYC, ARID1A, BCL2, KMT2D, and PIM1 as the most affected genes in B-cell lymphoma, with BCL2 and CREBBP predominant in HGBL DH, and MYC and PIM1 in HGBL NOS. Clonality analysis of immunoglobulin heavy and light chain rearrangements did not show distinguishable V- or J-usage between the diagnostic subgroups. Full article

Pediatric brain tumors are often noted to be different from their adult counterparts in terms of molecular features. Primary CNS lymphomas (PCNSLs) are mostly found in elderly adults and are uncommon in children and teenagers. There has only been scanty information about the molecular features of PCNSLs at a young age. We examined PCNSLs in 34 young patients aged between 7 and 39 years for gene rearrangements of BCl2, BCL6, CCND1, IRF4, IGH, IGL, IGK, and MYC, homozygous deletions (HD) of CDKN2A, and HLA by FISH. Sequencing was performed using WES, panel target sequencing, or Sanger sequencing due to the small amount of available tissues. The median OS was 97.5 months and longer than that for older patients with PCNSLs. Overall, only 14 instances of gene rearrangement were found (5%), and patients with any gene rearrangement were significantly older (p = 0.029). CDKN2A HD was associated with a shorter OS (p < 0.001). Only 10/31 (32%) showed MYD88 mutations, which were not prognostically significant, and only three of them were L265P mutations. CARD11 mutations were found in 8/24 (33%) cases only. Immunophenotypically, the cases were predominantly GCB, in contrast to older adults (61%). In summary, we showed that molecular findings identified in the PCNSLs of the older patients were only sparingly present in pediatric and young adult patients. Full article

To provide insights into targetable oncogenic pathways, this retrospective cohort study investigated the genetic profile of 26 patients with diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS), and two patients with high-grade B-cell lymphoma with MYC and BCL2 rearrangements (HGBCL) presenting in the ocular adnexa. Pathogenic variants and copy number variations in 128 B-cell lymphoma-relevant genes were analyzed by targeted next-generation sequencing. Genetic subtypes were determined with the LymphGen algorithm. Primary ocular adnexal DLBCL-NOS constituted 50% (n = 14) and was generally characterized by non-germinal center B-cell origin (non-GCB) (n = 8, 57%), and LymphGen MCD subtype (n = 5, 36%). Primary ocular adnexal DLBCL-NOS presented pathogenic variants in genes involved in NF-κB activation and genes which are recurrently mutated in other extranodal lymphomas of non-GCB origin, including MYD88 (n = 4, 29%), CD79B (n = 3, 21%), PIM1 (n = 3, 21%), and TBL1XR1 (n = 3, 21%). Relapsed DLBCL-NOS presenting in the ocular adnexa (n = 6) were all of non-GCB origin and frequently of MCD subtype (n = 3, 50%), presenting with a similar genetic profile as primary ocular adnexal DLBCL-NOS. These results provide valuable insights into genetic drivers in ocular adnexal DLBCL-NOS, offering potential applications in future precision medicine. Full article

Chromosomal rearrangements have been shown to alter genome organization, consequently having an impact on gene expression. Studies on certain types of leukemia have shown that gene expression can be exacerbated by the altered nuclear positioning of fusion genes arising from chromosomal translocations. However, studies on lymphoma have been, so far, very limited. The scope of this study was to explore genome organization in lymphoma cells carrying the t(14;18)(q32;q21) rearrangement known to results in over-expression of the BCL2 gene. In order to achieve this aim, we used fluorescence in situ hybridization to carefully map the positioning of whole chromosome territories and individual genes involved in translocation in the lymphoma-derived cell line Pfeiffer. Our data show that, although there is no obvious alteration in the positioning of the whole chromosome territories, the translocated genes may take the nuclear positioning of either of the wild-type genes. Furthermore, the BCL2 gene was looping out in a proportion of nuclei with the t(14;18) translocation but not in control nuclei without the translocation, indicating that chromosome looping may be an essential mechanism for BCL2 expression in lymphoma cells. Full article

High-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements are known for their aggressive clinical course and so are the ones with MYC and BCL2 protein overexpression. The optimal therapy for these lymphomas remains to be elucidated. A retrospective analysis of all diffuse large B-cell lymphomas and high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements diagnosed between 2017 and 2021 at the Institute of Oncology Ljubljana, Slovenia, has been performed. Only patients with double-expressor lymphoma (DEL), double-hit lymphoma (DHL), or triple-hit lymphoma (THL) were included. Demographic and clinical parameters were assessed, as well as progression-free survival (PFS) and overall survival (OS). In total, 161 cases out of 309 (161/309; 52,1%) were classified as DEL. Sixteen patients had DHL, MYC/BCL2 rearrangement was observed in eleven patients, and MYC/BCL6 rearrangement was observed in five patients. Five patients were diagnosed with THL. Out of 154 patients (according to inclusion/exclusion criteria) included in further evaluation, one-hundred and thirty-five patients had double-expressor lymphoma (DEL), sixteen patients had DHL, and three patients had THL. In total, 169 patients were treated with R-CHOP, 10 with R-CHOP and intermediate-dose methotrexate, 19 with R-DA-EPOCH, and 16 with other regimens. The median follow-up was 22 months. The 5-year OS for the whole DEL group was 57.1% (95% CI 45.9–68.3%) and the 5-year PFS was 76.5% (95% CI 72.6–80.4%). The log-rank test disclosed no differences in survival between treatment groups (p = 0.712) while the high-risk international prognostic index (IPI) carried a significantly higher risk of death (HR 7.68, 95% CI 2.32–25.49, p = 0.001). The 5-year OS for DHL patients was 32.4% (95% CI 16.6–48.2%) while all three TH patients were deceased or lost to follow-up. Our analyses of real-life data disclose that the R-CHOP protocol with CNS prophylaxis is a successful and curative treatment for a substantial proportion of DEL patients. Full article

During the progression of some cancer cells, the degree of genome instability may increase, leading to genome chaos in populations of malignant cells. While normally chaos is associated with ergodicity, i.e., the state when the time averages of relevant parameters are equal to their phase space averages, the situation with cancer propagation is more complex. Chromothripsis, a catastrophic massive genomic rearrangement, is observed in many types of cancer, leading to increased mutation rates. We present an entropic model of genome chaos and ergodicity and experimental evidence that increasing the degree of chaos beyond the non-ergodic threshold may lead to the self-destruction of some tumor cells. We study time and population averages of chromothripsis frequency in cloned rhabdomyosarcomas from rat stem cells. Clones with frequency above 10% result in cell apoptosis, possibly due to mutations in the BCL2 gene. Potentially, this can be used for suppressing cancer cells by shifting them into a non-ergodic proliferation regime. Full article

Deep learning applications are emerging as promising new tools that can support the diagnosis and classification of different cancer types. While such solutions hold great potential for hematological malignancies, there have been limited studies describing the use of such applications in this field. The rapid diagnosis of double/triple-hit lymphomas (DHLs/THLs) involving MYC, BCL2 and/or BCL6 rearrangements is obligatory for optimal patient care. Here, we present a novel deep learning tool for diagnosing DHLs/THLs directly from scanned images of biopsy slides. A total of 57 biopsies, including 32 in a training set (including five DH lymphoma cases) and 25 in a validation set (including 10 DH/TH cases), were included. The DHL-classifier demonstrated a sensitivity of 100%, a specificity of 87% and an AUC of 0.95, with only two false positive cases, compared to FISH. The DHL-classifier showed a 92% predictive value as a screening tool for performing conventional FISH analysis, over-performing currently used criteria. The work presented here provides the proof of concept for the potential use of an AI tool for the identification of DH/TH events. However, more extensive follow-up studies are required to assess the robustness of this tool and achieve high performances in a diverse population. Full article

Background: Ovarian tissue cryopreservation and transplantation are the only available fertility techniques for prepubertal girls with cancer. Though autotransplantation carries a risk of reintroducing malignant cells, it can be avoided by identifying minimal infiltrative disease (MID) within ovarian tissue. Methods: A broad search for peer-reviewed articles in the PubMed database was conducted in accordance with PRISMA guidelines up to March 2023. Search terms included ‘minimal residual disease’, ‘cryopreservation’, ‘ovarian’, ‘cancer’ and synonyms. Results: Out of 542 identified records, 17 were included. Ovarian tissues of at least 115 girls were evaluated and categorized as: hematological malignancies (n = 56; 48.7%), solid tumors (n = 42; 36.5%) and tumors of the central nervous system (n = 17; 14.8%). In ovarian tissue of 25 patients (21.7%), MID was detected using RT-qPCR, FISH or multicolor flow cytometry: 16 of them (64%) being ALL (IgH rearrangements with/without TRG, BCL-ABL1, EA2-PBX1, TEL-AML1 fusion transcripts), 3 (12%) Ewing sarcoma (EWS-FLI1 fusion transcript, EWSR1 rearrangements), 3 (12%) CML (BCR-ABL1 fusion transcript, FLT3) and 3 (12%) AML (leukemia-associated immunophenotypes, BCR-ABL1 fusion transcript) patients. Conclusion: While the majority of malignancies were found to have a low risk of containing malignant cells in ovarian tissue, further studies are needed to ensure safe implementation of future fertility restoration in clinical practice. Full article

BCL2, BCL6 and MYC are major oncogenes in B-cell lymphoma. Their aberrant activation frequently occurs via chromosomal translocations which juxtapose light or heavy chain immunoglobulin (IG) genes to BCL2 and MYC or fuse diverse partner genes with BCL6. So-called double-hit lymphomas usually carry BCL2 and MYC rearrangements, while triple-hit lymphomas additionally bear BCL6-fusions. All these translocations are of diagnostic relevance and usually denote poor prognosis. Here, we genomically characterized classic follicular lymphoma (FL) cell line SC-1, thereby identifying t(14;18)(q32;q21) juxtaposing IGH and BCL2, t(8;14)(q24;q32) juxtaposing IGH and MYC, and t(3;3)(q25;q27) fusing MBNL1 to BCL6. In addition, we found that SC-1 carries a novel chromosomal rearrangement, t(14;17)(q32;q21), which, though present at establishment, has remained unreported until now. We further show that t(14;17)(q32;q21) juxtaposes IGH with the HOXB gene cluster at 17q21 and affect the oncogenic activation of both homeobox gene HOXB5 and neighboring micro-RNA gene miR10a. Moreover, we detected aberrant overexpression of HOXB5 in subsets of Burkitt lymphoma, FL, and multiple myeloma patients, confirming the clinical relevance of its deregulation. In SC-1, HOXB5 activation was additionally supported by co-expression of hematopoietic stem cell factor ZNF521, indicating an aberrant impact in cell differentiation. Functional investigations showed that HOXB5 represses the apoptotic driver BCL2L11 and promotes survival in the presence of etoposide, and that miR10a inhibits BCL6 and may thus play an oncogenic role in later stages of lymphomagenesis. Collectively, we characterize triple-hit B-cell line SC-1 and identify the aberrant expression of HOXB5 and miR10a, both novel oncogenes in B-cell lymphoma. Full article