Aggressive Lymphoma Subtypes Research Articles

Primary Mediastinal Large B-cell Lymphoma – A Case Report

AbstractPrimary mediastinal large B-cell lymphoma (PMBL) is an uncommon and aggressive subtype of non-Hodgkin large B-cell lymphoma that affects patients in the third and fourth decades of life. The objective of the present report is to describe the case of a male patient admitted to the emergency room with symptoms of dyspnea associated with signs of superior vena cava syndrome. The imaging exams revealed two masses in the mediastinum; the definitive diagnosis, established through an anatomopathological examination and immunohistochemistry, was of PMBL, and the patient was referred for chemotherapy.

Exploring Differentially Expressed Genes and Immune Modulation in Diffuse Large B-Cell Lymphoma through RNA Sequencing Analysis.

Diffuse large B-cell lymphoma (DLBCL) is globally recognized as the most prevalent and aggressive subtype of non-Hodgkin lymphoma. While conventional treatments are effective initially, the disease can become resistant or relapse over time. This study aimed to examine the differentially expressed genes at the transcriptome level and molecular pathways in DLBCL patients. This investigation utilized RNA sequencing analysis to compare differentially expressed gene samples from five diffuse large B-cell lymphoma patients with two healthy volunteers. These participants were admitted to UKM Medical Center, Kuala Lumpur between 2019 and 2020. The differentially expressed genes were identified using the DESeq2 R package (version 1.10.1) using a negative binomial distribution model. The obtained P values were corrected with the Benjamin and Hochberg method and identified using a False Discovery Rate threshold of <0.05, with log2 fold change (FC) of ≥2 or ≤-2. Results showed 73 differentially expressed genes between the two groups, among which 70 genes were downregulated, and three genes were upregulated. The differentially expressed genes analyzed with the Reactome pathway were significantly associated with the downregulation of antimicrobial humoral response (P<0.001), neutrophil degranulation (P<0.001), chemokine receptors bind chemokines (P=0.028), defensins (P=0.028) and metabolism of angiotensinogen (P=0.040). These findings suggest that the identified pathways may contribute to cancer progression and weaken the immune response in diffuse large B-cell lymphoma patients. This study offers fresh insights into previously undiscovered downstream targets and pathways modulated by diffuse large B-cell lymphoma.

Pirtobrutinib: First Non-covalent Tyrosine Kinase Inhibitor for Treating Relapsed or Refractory Mantle Cell Lymphoma in Adults.

Mantle Cell Lymphoma (MCL) is an aggressive subtype of Non-hodgkin's Lymphoma (NHL). Bruton Tyrosine Kinase (BTK) is a non-receptor tyrosine kinase, and is one of the therapeutic targets for B-cell-driven malignancies. Approved covalent BTK inhibitors such as ibrutinib, acalabrutinib, and zanubrutinib are associated with treatment limitations due to off-target side effects and the development of C481 substitution resistance mutations. Pirtobrutinib was approved by the US FDA on January 27, 2023, for the treatment of relapsed or refractory mantle cell lymphoma, including the resistance to covalent BTK inhibitors. In this perspective, physicochemical properties, synthesis, dosage and administration, mechanism of action, pharmacodynamics, pharmacokinetics, drug interactions, and treatment-emergent adverse events of pirtobrutinib are discussed.

Clinical Approach to Advanced Mantle Cell Lymphoma: A Detailed Case Analysis

Mantle cell lymphoma (MCL) is a rare and aggressive subtype of non-Hodgkin lymphoma (NHL) originating from cells in the mantle zone. Herein, we present a case report of a 49-year-old male patient diagnosed with stage VI MCL, illustrating various diagnostic methods and procedures utilized in his evaluation. The patient presented with progressively enlarging cervical lymph nodes, fatigue, weight loss, anorexia, chronic diarrhea, abdominal pain, and rectal bleeding. Clinical examination revealed cutaneomucosal pallor, tachycardia, expiratory polypnea, bilateral jugulocarotid adenopathies, and splenomegaly. Laboratory investigations showed normocytic normochromic anemia, hyperleukocytosis, lymphocytic predominance, and thrombocytopenia. Peripheral blood smear analysis indicated a lymphoproliferative disorder, confirmed by flow cytometry revealing monotypic lymphoid cells. Bone marrow biopsy showed hypoplastic marrow with atypical cells. Immunohistochemistry confirmed mantle cell lymphoma localization. Subsequent thoraco-abdomino-pelvic CT scan revealed mediastinal and abdominal adenopathy with splenomegaly, leading to a diagnosis of stage IV MCL. The case highlights the importance of early and comprehensive diagnostic approaches in MCL management.

Abstract PO-025: Identifying tissue-specific drivers of immune evasion in Mantle Cell Lymphoma at single cell level

Abstract Background: Mantle cell lymphoma (MCL) is an aggressive subtype of B-cell non-Hodgkin lymphoma that exhibits clinical, pathological, and genetic heterogeneity. While generally thought to be incurable, recently demonstrated clinical activity of both chimeric antigen receptor T (CAR-T) cells and bispecific antibodies suggest that immune-mediated therapies offer substantial benefit in this disease and underscores the value of understanding mechanisms of immune evasion in this disease. Aim: The aim of this project is to uncover distinct cellular networks driving immune evasion in MCL across disease sites. Methods: We analyzed 10 archival samples collected from 8 clinically annotated patients with untreated MCL, including mononuclear cells from peripheral blood (PB), lymph nodes (LN) and bone marrow (BM). After generating single-cell suspensions from tumors, we performed Cellular Indexing of Transcriptomes and Epitopes sequencing (CITE-seq) and identified malignant B cells based on the co-expression of cyclin D1 (CCND1) and B cell markers (MS4A1, CD79A, CD79B). B and T cells were then subclustered using a reference mapping geneset. Molecular signatures database was utilized to perform geneset enrichment analysis (GSEA). Results: Our study first confirms the heterogeneity of mantle cell lymphoma across compartments (i.e PB, LN, BM), showing 5 different clusters of malignant cells, with different abundance in cell proportion among patients. We found that malignant B cells expressed different levels of CCND1 expression across tissue compartments. Furthermore, we identified a specific cluster of malignant cells, enriched in the PB, marked by decreased expression of the costimulatory receptor CD40 and higher levels of B-cell receptor signaling. This may explain the rapid response of circulating MCL cells to Bruton Tyrosine Kinase (BTK) inhibition. Interestingly, the higher expression of CD40 on LN-resident MCL cells suggests that MCL cells may co-opt LN-resident T-cells to support their growth, as has been previously described. Consistent with this, T-cells from LN were phenotypically exhausted, suggesting that MCL cells within the LN leverage local interactions with T-cells to promote survival while avoiding T-cell-driven cytotoxicity. Finally, we also found that high level of Ki67 correlates with myeloid-cell abundance in the TME suggesting that monocytes may support tumor cell proliferation. Conclusion: These results provide a deeper understanding of tissue-specific heterogeneity in MCL, including distinct tumor-immune interactions at different tissue sites. In ongoing analyses, we will correlate these findings with patient outcomes and response to BTK inhibition and are currently analyzing samples from patients with relapsed disease to identify microenvironmental features associated with disease progression. Citation Format: Amira Marouf, Jahan Rahman, Ashlee Joseph, Irem Isgor, Ya-Hui Lin, Ronan Chaligne, Shenon Sethi, Ahmet Dogan, Gilles Salles, Anita Kumar, Santosha A Vardhana. Identifying tissue-specific drivers of immune evasion in Mantle Cell Lymphoma at single cell level [abstract]. In: Proceedings of the Fourth AACR International Meeting on Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2024 Jun 19-22; Philadelphia, PA. Philadelphia (PA): AACR; Blood Cancer Discov 2024;5(3_Suppl):Abstract nr PO-025.

Racial disparities in the incidence and survival outcomes in diffuse large B-cell lymphoma in adolescents and young adults.

Diffuse large B-cell Lymphoma (DLBCL) is an aggressive subtype of non-Hodgkin lymphoma (NHL). The disease generally occurs in older patients. Although at a lower prevalence, the disease also occurs in the adolescent and young adult group (AYA). There is paucity of data in the literature on racial and ethnic disparities in the incidence and survival outcomes of DLBCL in the AYA group. The objective of our study is to demonstrate the disparities in these outcomes. Utilizing SEER, we obtained data on patient demographics, incidence, and survival from 2000 to 2020. We observed statistically significant reduced incidence of DLBCL in all racial groups, except the non-Hispanic Asian and Pacific Islander group (NHAPI). The non-Hispanic Black group (NHB) had one of the lowest survival despite showing the largest decrease in incidence in DLBCL. The differences in the survival could be secondary to socioeconomic factors, however other reasons need to be explored. The increased incidence among the NHAPI group mirrors that of large population-based studies in East Asian countries, however, underlying reasons have not been elucidated.

PRMT5 activates lipid metabolic reprogramming via MYC contributing to the growth and survival of mantle cell lymphoma

Mantle cell lymphoma (MCL) is an incurable and aggressive subtype of non-Hodgkin B-cell lymphoma. Increased lipid uptake, storage, and lipogenesis occur in a variety of cancers and contribute to rapid tumor growth. However, no data has been explored for the roles of lipid metabolism reprogramming in MCL. Here, we identified aberrant lipid metabolism reprogramming and PRMT5 as a key regulator of cholesterol and fatty acid metabolism reprogramming in MCL patients. High PRMT5 expression predicts adverse outcome prognosis in 105 patients with MCL and GEO database (GSE93291). PRMT5 deficiency resulted in proliferation defects and cell death by CRISPR/Cas9 editing. Moreover, PRMT5 inhibitors including SH3765 and EPZ015666 worked through blocking SREBP1/2 and FASN expression in MCL. Furthermore, PRMT5 was significantly associated with MYC expression in 105 MCL samples and the GEO database (GSE93291). CRISPR MYC knockout indicated PRMT5 can promote MCL outgrowth by inducing SREBP1/2 and FASN expression through the MYC pathway.

Prediction of immunochemotherapy response for diffuse large B-cell lymphoma using artificial intelligence digital pathology.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous and prevalent subtype of aggressive non-Hodgkin lymphoma that poses diagnostic and prognostic challenges, particularly in predicting drug responsiveness. In this study, we used digital pathology and deep learning to predict responses to immunochemotherapy in patients with DLBCL. We retrospectively collected 251 slide images from 216 DLBCL patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), with their immunochemotherapy response labels. The digital pathology images were processed using contrastive learning for feature extraction. A multi-modal prediction model was developed by integrating clinical data and pathology image features. Knowledge distillation was employed to mitigate overfitting on gigapixel histopathology images to create a model that predicts responses based solely on pathology images. Based on the importance derived from the attention mechanism of the model, we extracted histological features that were considered key textures associated with drug responsiveness. The multi-modal prediction model achieved an impressive area under the ROC curve of 0.856, demonstrating significant associations with clinical variables such as Ann Arbor stage, International Prognostic Index, and bulky disease. Survival analyses indicated their effectiveness in predicting relapse-free survival. External validation using TCGA datasets supported the model's ability to predict survival differences. Additionally, pathology-based predictions show promise as independent prognostic indicators. Histopathological analysis identified centroblastic and immunoblastic features to be associated with treatment response, aligning with previous morphological classifications and highlighting the objectivity and reproducibility of artificial intelligence-based diagnosis. This study introduces a novel approach that combines digital pathology and clinical data to predict the response to immunochemotherapy in patients with DLBCL. This model shows great promise as a diagnostic and prognostic tool for clinical management of DLBCL. Further research and genomic data integration hold the potential to enhance its impact on clinical practice, ultimately improving patient outcomes.

Abstract 3834: Plasmablastic lymphoma provisional prognostic score

Abstract Background Plasmablastic Lymphoma (PBL) is a rare and aggressive subtype of non-Hodgkin's lymphoma. It tends to be associated with immunosuppressive clinical contexts, such as HIV infection and immunosuppressive therapies for autoimmune disorders and organ transplants. However, due to the rarity of the disease, which needs to be better understood, varied treatment approaches have been implemented, and no optimal data or guidelines for managing PBL are available. Therefore, we conducted this study to develop a provisional PBL prognostic score (PBLPS) for this rare disease. Methods We used our constructed PBL database, which contains retrospective data on 300 cases. Such data included demographics such as sex, age, and race. It also included disease presentation symptoms, duration of symptoms before diagnosis, site(s) of the disease, blood counts, coexisting comorbidities, disease immunohistochemical and molecular phenotype, types of treatment, and survival outcomes. Of the 300 cases, 291 had complete survival and outcomes data, the sample chosen for this study. Cox proportional-hazards model and Log-rank tests were used to assess the influence of clinicopathologic factors on overall survival (OS). We included factors that statistically impacted OS and scored them by the impact of their hazard ratios. Results The median OS of the cohort was 25 months. The following dichotomous variables were identified as impactful prognostic factors in this cohort: LDH&amp;gt;500 (p=0.04), CD4&amp;lt;100 (p=0.006), bone marrow (BM) involvement (p&amp;lt;0.0001), EBER-negative (p=0.01), HHV8+ (p=0.02), and involvement of liver (p=0.003), lungs/pleura (p&amp;lt;0.0001), and upper GI tract (p=0.001). A prognostic model was devised using these variables to identify different levels of risk. Involvement of BM and involvement of any of the worse prognosis organs (liver, lung/pleura, and/or upper GI tract) were each assigned a score of 2 when present. CD4&amp;lt;100, EBER-negative, and LDH&amp;gt;500 were assigned 1 point each as they had the lowest hazard ratios of all the other variables. In this exploratory cohort, we assigned low risk a score of 0, intermediate risk a score of 1-2, and high risk a score of 3-7. This prognostic score system led to our cohort's most optimal risk discriminatory model, where low, intermediate, and high risk had a median OS of NR, 15, and 4 months, respectively (p&amp;lt;0.0001). Conclusion This PBLPS is a promising new tool for risk-stratifying patients with PBL. However, it still requires prospective validation. Citation Format: Philip A. Haddad, Jaren Lerner. Plasmablastic lymphoma provisional prognostic score [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3834.

Abstract 2840: Development, characterization, and validation of a systemic human mantle cell lymphoma model utilizing luciferase expressing Jeko-1 tumor cells

Abstract Mantle cell lymphoma (MCL) is an aggressive subtype of B-cell non-Hodgkin lymphoma that is clinically and biologically heterogenous. MCL murine models are scarce and reliable in vivo models are necessary for pre-clinical testing and identification of improved novel therapeutics. To address this need, we established and characterized a human MCL in vivo model by systemic implantation of the luciferase-expressing Jeko-1 cell line (Jeko-1-luc) into immunodeficient NCG mice. Tumor growth kinetics was evaluated by testing multiple cell inoculums, and disease progression was monitored by in vivo serial bioimaging, three-dimensional optical imaging (3D), and ex-vivo endpoint analyses. Jeko-1-luc tumor growth profile revealed moderate latency with a median survival of 40 days post implant. Subsequently, we utilized 3D optical imaging and ex-vivo imaging that confirmed the localization of tumor growth predominantly in lungs, spleen, and skeletal regions. Additionally, we determined the surface expression of selected B-cell lineage markers including CD19, CD20, and CD22. Next, we evaluated the efficacy and effect on survival in response to various standard of care agents including Vincristine, Rituximab, Palbociclib, Temsirolimus, and Cyclophosphamide. The quantification of tumor burden by in vivo and ex-vivo bioluminescent imaging demonstrated that the highest therapeutic activity and overall survival was achieved by Palbociclib and Vincristine. Flow cytometric analyses further demonstrated that tumor cells obtained from blood and selected tissues including spleen and bone marrow showed reduced tumor burden in treatment groups relative to the control group. Taken together, these results illustrate the translational value of the Jeko-1-luc model and provides a platform for evaluating novel treatment modalities for mantle cell lymphoma. Citation Format: David Harris, Andrew Wong, Elizabeth Rainbolt, Nicole Westrick, Justin Avery, Joseph Kolb, Aswani Vunnava, Zachary Ward, Chassidy Hall, Bincy John. Development, characterization, and validation of a systemic human mantle cell lymphoma model utilizing luciferase expressing Jeko-1 tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2840.

Zanubrutinib plus Cytarabine in Patients with Refractory/Relapsed Primary Central Nervous System Lymphoma

Introduction: Primary central nervous system lymphoma (PCNSL) is a rare subtype of aggressive extranodal non-Hodgkin lymphoma. Currently, there is no standard of care for the treatment of refractory or relapsed PCNSL (r/r PCNSL). We conducted a prospective single-arm phase II study to evaluate zanubrutinib plus cytarabine for r/r PCNSL. Methods: Using Simon’s two-stage design, we analyzed 34 patients who received high-dose cytarabine (3.0 g/m2 once daily) for 2 days and zanubrutinib (160 mg twice daily) for 21 days each cycle for up to 6 cycles. The study was registered at www.chictr.org.cn as #ChiCTR2000039229. Results: The median follow-up was 19 months. The overall response rate was 64.7% (95% confidence interval [CI], 47.9–78.5%) with a complete remission or unconfirmed complete remission rate of 47.1% (16/34) and a partial remission rate of 17.6% (6/34). The median progression-free survival was 4.5 months (95% CI, 1.5–9.4), and the median OS was 18 months (95% CI, 9.5 to not estimable). The median duration of the response was 9 months (95% CI, 3.2 to not estimable). The most common treatment-emergent adverse events were thrombocytopenia (55.9%). No treatment-related death occurred. Conclusion: Zanubrutinib and cytarabine showed efficacy in r/r PCNSL with an acceptable safety profile.

Twenty Years of Advancing Discoveries and Treatment of Mantle Cell Lymphoma.

Mantle cell lymphoma (MCL) is an aggressive subtype of non-Hodgkin lymphoma characterized by the t(11;14) chromosomal translocation, which leads to the dysregulation of the cell cycle through overexpression of cyclin D1. Although advances in treatment have improved outcomes, in particular the introduction of Bruton tyrosine kinase inhibitors to the treatment armamentarium and more recently chimeric antigen receptor T-cell therapy, MCL often rapidly develops resistance and has a high rate of relapse. In addition, MCL is clinically heterogeneous. Response to treatment can vary, making it difficult to establish a standard treatment approach. Thus, there remains a significant need for more research on MCL biology, including those molecular mechanisms underpinning treatment response or lack thereof, so that novel agents may be identified and/or the use of existing agents may be optimized. At the Lymphoma Research Foundation's 20th MCL Scientific Consortium and Workshop, researchers gathered to discuss recent developments in both basic scientific and clinical research to continue to develop an understanding of MCL and improve outcomes for patients. This report, which includes a summary of each presentation, reviews the findings presented at the workshop and highlights opportunities, open questions, and areas for future study that would pave the way for a cure for this disease in the coming decades.

Biological signatures of the International Prognostic Index in diffuse large B-cell lymphoma

AbstractDiffuse large B-cell lymphoma (DLBCL) is a highly aggressive subtype of lymphoma with clinical and biological heterogeneity. The International Prognostic Index (IPI) shows great prognostic capability in the era of rituximab, but the biological signatures of IPI remain to be discovered. In this study, we analyzed the clinical data in a large cohort of 2592 patients with newly diagnosed DLBCL. Among them, 1233 underwent DNA sequencing for oncogenic mutations, and 487 patients underwent RNA sequencing for lymphoma microenvironment (LME) alterations. Based on IPI scores, patients were categorized into 4 distinct groups, with 5-year overall survival of 41.6%, 55.3%, 71.7%, and 89.7%, respectively. MCD-like subtype was associated with age of >60 years, multiple extranodal involvement, elevated serum lactate dehydrogenase (LDH), and IPI scores ranging from 2 to 5, whereas ST2-like subtype showed an opposite trend. Patients with EZB-like MYC+ and TP53Mut subtypes exhibited poor clinical outcome independent of the IPI; integrating TP53Mut into IPI could better distinguish patients with dismal survival. The EZB-like MYC−, BN2-like, N1-like, and MCD-like subtypes had inferior prognosis in patients with IPI scores of ≥2, indicating necessity for enhanced treatment. Regarding LME categories, the germinal center–like LME was more prevalent in patients with normal LDH and IPI scores of 0 to 1. The mesenchymal LME served as an independent protective factor, whereas the germinal center–like, inflammatory, and depleted LME categories correlated with inferior prognosis for IPI scores of 2 to 5. In summary, our work explored the biological signatures of IPI, thus providing useful rationale for future optimization of the IPI-based treatment strategies with multi-omics information in DLBCL.

A Case of Plasmablastic Lymphoma Complicated with Pure Red Cell Aplasia Caused by T-cell Large Granular Lymphocytic Leukemia.

Plasmablastic lymphoma (PBL) is an aggressive subtype of large B-cell lymphoma associated with immunodeficient states, such as HIV and EBV infections, and aging. PBL frequently harbor STAT3 mutations, which are crucial for their development. We herein report a rare case of PBL complicated by T-cell large granular lymphocytic leukemia (T-LGLL) and pure red cell aplasia (PRCA). The patient was treated with six cycles of chemotherapy and developed transfusion-dependent anemia. Large granular lymphocytes and T-cell receptor rearrangement were detected, thus leading to the diagnosis of T-LGLL and PRCA. This is the first documented case of PBL with T-LGLL and PRCA, offering insight into PBL's pathophysiology and the complications of PBL.

Polatuzumab vedotin combined with bendamustine and rituximab for relapsed/refractory diffuse large B-cell lymphoma: A systematic review protocol.

Diffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin lymphoma subtype with a significant relapse rate and poor prognosis in relapsed/refractory (R/R) patients. Polatuzumab vedotin in combination with bendamustine and rituximab (Pola-BR) has demonstrated promising efficacy and safety as salvage therapy for R/R DLBCL. This systematic review protocol aims to comprehensively evaluate the efficacy of Pola-BR for the treatment of R/R DLBCL by synthesizing data from relevant randomized controlled trials. This protocol details the eligibility criteria, search strategy, study selection, data extraction, and analysis methods for the systematic review. Randomized controlled trials comparing Pola-BR with other interventions for R/R DLBCL will be included. The primary endpoint is overall survival, with secondary endpoints being progression-free survival and incidence of adverse events. A comprehensive search will be conducted across databases such as Medline/PubMed, Cochrane Library, Web of Science, Scopus, EMBASE, ProQuest, EU Clinical Trials Register, WHO International Clinical Trials Registry Platform (ICTRP), and ClinicalTrials.gov from the January 2000 to April 2024. To assess the potential risk of bias, the Cochrane Risk of Bias 1 tool will be used. Data synthesis will utilize fixed-effect or random-effects models, and subgroup and meta-regression analyses will examine heterogeneity. Additionally, publication bias and sensitivity analyses will be performed, and the GRADE approach will be applied to assess the certainty of the evidence. This systematic review and meta-analysis protocol provides a rigorous framework for evaluating the efficacy of Pola-BR in the treatment of R/R DLBCL. The results will inform clinical decision-making and guideline development, addressing the unmet need for effective and tolerable treatments for this challenging patient population. Potential limitations and biases will be acknowledged, and future research directions will be discussed.

Racial Disparities in the Incidence and Survival Outcomes in Diffuse Large B-Cell Lymphoma in Adolescents and Young Adults

Background Diffuse Large B-Cell Lymphoma (DLBCL) is an aggressive subtype of non-Hodgkin lymphoma, and generally occurs most frequently in Whites, with a median age of 64 years 1. Adolescent and Young Adult (AYA) cancer is defined as cancer in individuals 15 to 39 years old 2. There is paucity of data on racial and ethnic disparities in the incidence of DLBCL in AYA. We aim to determine the influence of race on the incidence and survival outcomes of DLBCL in the AYA cohort. Methods Data from the Surveillance, Epidemiology, and End Results (SEER) 17 Research Plus database program was utilized to obtain the annual percentage change (APC) in incidence of DLBCL from 2000 - 2020 for patients aged 15 - 39 years (AYA group). Patient characteristics were expressed in proportions (%). The Kaplan Meier method was used to determine overall survival (OS) and cancer-specific survival (CSS). Cox regression was performed to determine predictors of survival. A p-value ≤0.05 was considered statistically significant. Results We identified a total of 8735 AYA patients diagnosed with DLBCL (see Table). The proportion of patients with DLBCL decreased the most in Non Hispanic Blacks (NHB, 45% vs 55%, p-value ≤0.001) and Non-Hispanic Whites (NHW, 45% vs 55%, p-value ≤0.001), followed by Non-Hispanic American Indian/Alaska Natives (NHAIAN, 48% vs 52%, p-value ≤0.001). No change was noted in the Hispanic (all races) group (50% vs 50%, p-value ≤0.001). The Non-Hispanic Asian/Pacific Islander (NHAPI) group showed the highest proportion of patients with DLBCL (58%) in 2011-2020 compared to 2000-2010 (42%), p-value ≤0.001. Over the study period (2000 - 2020), there was a significant decrease in the yearly incidence of DLBCL in the overall AYA cohort (APC: -0.5%, p &amp;lt;0.05). This reduction was most pronounced in NHB (APC: -1.4%, p-value ≤0.001), followed by Hispanics, all races (APC: -0.65%, p-value ≤0.001) and NHW (-0.57%, p ≤0.04). However, there was a significant increase in the incidence of DLBCL in NHAPI (APC: 1.88%, p-value ≤0.001) during the same time period. OS for NHAIAN was 58 months (95% CI: 21-147, p ≤0.001), 63 months (95% CI: 19-139, p-value ≤0.001) for NHAPI; 63 months (95% CI: 13-142, p ≤0.001) for NHB; 58 months (95% CI 14-134, p≤0.001) for Hispanics, all races; and 98 months (95% CI: 31-172, p≤0.001) for NHW. The 5 and 10-year CSS were 86.5% and 85.4% for NHW (p-value ≤0.001); 85.4% and 84.4% for NHAPI (p ≤0.001); 81.3% and 80.3% for Hispanics, all races (p ≤0.001); 68.1% and 68.1% (p ≤0.001) for NHAIAN; and 71.9% and 69.4% for NHB (p-value ≤0.001) (see Figure).In the multivariable model, NHB (HR = 1.91, 95%, CI: 1.70-2.15, p ≤0.001), NHAIAN (HR = 2.09, 95% CI: 1.29-3.38, p≤0.003) and Hispanic, all races (HR 1.35, 95% CI: 1.20-1.53, p≤0.001) were associated with reduced odds of survival, compared to NHW. Conclusion There is a significant racial/ethnic disparity in the incidence and outcomes of DLBCL among AYA patients. Increase in incidence of DLBCL was observed only in NHAPI. Despite the significant improvement in the incidence of DLBCL in NHB over the years, odds of survival remain poorer than other racial/ethnic groups, except NHAIAN. More studies are needed to explore the reasons for these racial differences and more concerted efforts are needed to improve outcomes among AYA patients.

Lymphoma-Derived IL-10 Is a Key Immunomodulatory Factor at the Tumor Microenvironment of Activated B-Cell Diffuse Large B-Cell Lymphoma and Influences In Vivo Responses to Immunotherapy

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of aggressive non-Hodgkin's lymphoma with ~40% of patients experiencing refractory or relapsed disease to R-CHOP immunochemotherapy. These higher risk patients often exhibit gene expression profiles that resemble a late germinal center-derived activated B-cell (ABC) phenotype, where diverse specific mutations in genes along BCR and TLR signaling pathways converge into constitutive activation of the NF-κB pathway. Identification of factors that contribute to the survival of malignant ABC-DLBCL cells is crucial for designing specific interventions. In this setting, previous in vitro studies in DLBCL cell lines have evidenced that IL-10 is a direct target of NF-κB signaling that sustains lymphoma cell survival by an auto-stimulatory loop via STAT3 signaling. However, the action of IL-10 could be more complex within the lymphoma microenvironment, as IL-10 can have both stimulatory and inhibitory effects depending on the cellular source of IL-10, the timing of its secretion, and the type of immune cells that receives signals via IL-10 receptor (IL-10R). To explore in vivo the relevance of lymphoma-derived IL-10, we have generated a novel quintuple transgenic mouse model that we call pBIC10, after crossing our previous ABC-DLBCL-like pBIC mice carrying constitutive NF-κB signaling (Pascual et al., Blood 2019) to mice with a floxed Il10 gene for conditional knock-out of IL-10 specifically in malignant ABC-DLBCL cells. As expected, increased intracellular IL-10 signaling was detected in primary murine DLBCL cells from pBIC mice but not in IL-10 deficient pBIC10 mice, which promoted lymphoma cell survival ex vivo as revealed by perturbation studies of the IL-10/JAK1/STAT3 autocrine loop with blocking monoclonal antibodies or selected inhibitors. However, in vivo genetic deletion of lymphoma-derived IL-10 did not offer improved overall survival but, on the contrary, notably accelerated DLBCL progression in pBIC10 mice (Figure 1A, left). A comprehensive integration of multiparametric flow cytometry and transcriptomic analyses using bulk and single-cell RNA-seq of lymphoma cells and the tumor microenvironment coupled with BCR- and TCR-seq, identified lymphoma-derived IL-10 as a key immunomodulator of the DLBCL microenvironment, including unexpected protective paracrine functions in the progression of DLBCL. By comparing IL-10-proficient (pBIC) and -deficient (pBIC10) murine DLBCL models, we observed a multifaceted role of IL-10 produced by DLBCL cells, enabling immune-effector processes (facilitating immune chemotaxis, antigen presentation, and IFNγ responses) that yielded higher percentages of long-lived stem-like CD8 +TCF-1 +PD-1 lo/int T cells and dendritic cells, while restraining PD-1/LAG3-driven T-cell exhaustion and reducing immunosuppression by CD4 +CD25 +FOXP3 + regulatory T (Treg) cells. Thus, depletion of lymphoma-derived IL-10 decreased T-cell cytotoxicity and increased Treg-driven immunosuppression, which collectively accelerated lymphoma development. Consequently, T-cell targeted immune-checkpoint therapy (with anti-PD-1 antibodies) was effective only in IL-10-proficient DLBCL but not in IL-10-deficient pBIC10 mice (Figure 1A, right). Further comparative studies between pBIC and pBIC10 mice showed that tumor vascularization and expression of B-cell calcium channels, which have been previously associated with sensitivity to rituximab, were counteracted by lymphoma-derived IL-10. Accordingly, anti-CD20-based targeting of lymphoma cells (with rituximab surrogate antibodies) showed best in vivo responses in IL-10-deficient DLBCL mice with respect to pBIC mice (Figure 1A, right). Consistent with this preclinical data, analyses of transcriptional IL-10-associated hallmarks to stratify DLBCL patients (Schmitz et al., NEJM 2018) identified better clinical responses to R-CHOP in patients with pBIC10-like DLBCL phenotype (Figure 1B). Collectively, our study provides new functional and mechanistic insights into the role of lymphoma-derived IL-10 in the pathogenesis of DLBCL and the restraint of an immunosuppressed tumor microenvironment, which holds predictive potential as a biomarker for immunotherapy responses in DLBCL.

B-Cell Maturation Antigen (BCMA) Expression and Clinical Features of Plasmablastic Lymphoma (PBL)

Introduction: Plasmablastic lymphoma (PBL) is a rare and aggressive subtype of large B-cell lymphoma with plasmacytic differentiation. Although limited-stage (LS) PBL has a favorable outcome, extensive-stage (ES) PBL has a poor prognosis, with a median survival of 12-18 months. Patients with relapsed/refractory (r/r) PBL have limited treatment options and most die from the disease. B cell maturation antigen (BCMA) - directed cellular and immunotherapies are highly effective in MM. The data on BCMA expression in PBL is limited. Literature review identified one report including 7 PBL cases all of which expressed BCMA. We studied all patients with a diagnosis of PBL who presented to Moffitt Cancer Center in Florida, USA from Jan. 2006 to Apr. 2023, and retrospectively performed BCMA immunohistochemistry (IHC) staining on the available archived FFPE biopsy samples. Methods: Progression-free survival (PFS) was calculated as time from disease progression or last follow up to treatment start date. Overall survival (OS) was calculated as time from death or last follow up to date of PBL diagnosis. Association of BCMA expression with PFS or OS was evaluated using logrank test, with continuous variables converted to categorical by classifying as above or below median. All analyses were done using SAS 9.2. Results: A total of 32 PBL patients were identified. The median age was 59 years (range 31-83 years); 21 (65.6%) had stage III/IV (ES); 9 patients (28.1%) were HIV positive; and 57.1% of evaluated cases were EBV positive by EBER. Treatment data was available for 30 patients. The most common frontline therapies were EPOCH and CHOP with or without rituximab; four patients received bortezomib combined with EPOCH; 7 patients (23.3%) received autoSCT in 1 st remission (Table 1). Median follow-up was 77.6 months calculated using the reverse Kaplan-Meier method. Consistent with previous reports, patients with ES PBL had worse outcome than those with LS PBL, with 3-year OS rates of 24% and 100%, respectively, p=0.01 (Table 1). Among the 20 patients with ES PBL and known treatment responses, 11 did not achieve CR after frontline therapy. Ten of these 11 patients died due to disease progression, 9 within 2 years and 1 within 3 years. Two patients received CD19 CAR-T after multiple lines of therapy. Both died within 30 days, one from disease progression and the other from multiple treatment complications. Out of the 18 cases with tissue available for IHC study, 17 (94.4%) had positive BCMA expression (Figure 1). The median percentage of BCMA+ cells was 75% (Table 1). Eleven (61.1%) cases had intermediate to strong BCMA staining. Neither BCMA+ cell percentage nor BCMA expression level was associated with disease stage, response rate, PFS, or OS (p&amp;gt;0.10 for all tests). Discussion: In our study the majority of our PBL cases tested positive for BCMA, and the percentage of BCMA+ cells seemed comparable to MM cases.To our knowledge, this is the largest and the first report that systemically evaluated BCMA expression in PBL. Our results provide evidence to explore BCMA as a potential target in PBL. Currently two anti-BCMA CAR-T products and an anti-BCMA/CD3 bispecific T-cell engager have been approved for r/r MM. A BCMA-targeting antibody-drug conjugate (ADC) Belantamab mafodotin-blmf was initially granted accelerated approval by FDA for r/r MM but was later voluntarily withdrawn from the market. Given the expression of BCMA in PBL and the lack of effective treatment of r/r PBL, these patients could be considered in trials evaluating the BCMA-targeting therapies. In fact, in a case report recently published, one patient with refractory PBL achieved CR after one infusion of BCMA CAR-T and remained in CR after 14 months. Ten of our 11 ES patients who did not achieve CR after frontline chemotherapy died from the disease, emphasizing the importance of clinical trials for this condition. We did not find an association of BCMA expression with clinical outcomes as oppose of MM, in which higher BCMA expression was associated with shorter PFS and OS. The lack of association in our study may be due to the small sample size, or, it may reflect a difference in biological role of BCMA in PBL from MM. Our results will need to be corroborated with other series to confirm our findings. Translational studies need to evaluate the dynamics of BCMA protein expression on PBL cell membrane and the activity of BCMA-targeting agents in vitro and in animal models of PBL.

A Retrospective Analysis of the Trends in Mantle Cell Lymphomas in the United States

Introduction: Mantle Cell Lymphoma (MCL) refers to the malignant B lymphocytes arising from the outer (mantle) zone of the lymphoid follicle. This rare and aggressive subtype of Non-Hodgkin Lymphoma, which accounts for ~5 percent of all NHL cases. It is associated with t(11:14) that leads to over-expression of cyclin D1, resulting in tumor cell proliferation via cell cycle dys-regulation, chromosomal instability, and epigenetic regulation. The aim of this study is to understand the epidemiology and survival predictors of MCL. Methods: The data was collected from Surveillance, Epidemiology and End Result database Research Plus Data, 17 Registries, Nov 2022 Sub (2000-2020). We extracted Mantle Cell Lymphoma cases diagnosed after 20 years of age, with Lymphoid neoplasm recode 2(a)2.1.3. The analysis was stratified based on age, sex, racial incidence rates, &amp; survival curves based were compared, using the Log-rank test (GraphPad Prism). Results: A total of 14166 cases of MCL were found between 2000 to 2020. Out of these, ~70.73% cases were males, and ~29.27% were females. The median age at the time of diagnosis was 69 years. Of the affected population, ~80.60% were Caucasians, ~3.92% were African-Americans, ~4.10% were Asians/Pacific Islanders, only ~0.50% were American Indians/Alaskan Natives, and ~10.32% were Hispanics. The incidence per 1,000,000, as of 2020, was 10.83 for the general population, 13.00 for Caucasians, 5.01 for African-Americans, 13.71 for American Indians/Alaskan Natives, 3.28 for Asians/Pacific Islanders, and 9.43 for Hispanics. Survival curves were not significant when compared based on the race of the patients. However, survival curves showed statistical significance when compared based on gender, with median of survival (mOS) for males was 50 months, and for females mOS was 56 months (p-value 0.0.008, Hazard Ratio 1.084 [Confidence Interval 1.035 to 1.136], using Log-rank test. Conclusions: Mantle Cell Lymphoma has a strong predilection for males. It is more commonly diagnosed in the late 60s, median age being 69. Unequal racial distribution was noted, with caucasians (~80%) comprising most of the patient population, and the least commonly encountered were American Indians/Alaskan Natives(~0.50%). However, when incidence rates were calculated per 1,000,000 population in 2020, it was found that the incidence in American Indians/Alaskan Natives (13.71), is drastically higher than the general population(10.83) vs. incidence in Asians/Pacific Islanders(3.28) is significantly lower than the other races. Although race played no role in prognosis, females had better survival rates than males. This retrospective study was done to aid in better understanding of this curable malignancy, despite its rarity, aggressivity and the complexity in treatment.

Plasmablastic Lymphoma Descriptors and Clinicopathologic Determinants of Survival: Analysis of a Pooled Database

Background Plasmablastic Lymphoma (PBL) is a rare and aggressive subtype of non-Hodgkin's lymphoma. It tends to be associated with immunosuppressive clinical contexts, such as HIV infection and immunosuppressive therapies for autoimmune disorders and organ transplants. However, due to the rarity of the disease, which is poorly understood, varied treatment approaches have been implemented, and no optimal data or guidelines for managing PBL are available. Furthermore, a few small case series reported conflicting prognosticators. Therefore, we conducted this pooled database analysis to identify the prognostic factors, clinicopathological characteristics, and therapeutic strategies influencing survival in this rare disease. Methods To study the demographic characteristics, molecular and immunohistochemical signatures, therapeutic interventions, survival, and prognostic factors, we compiled a pooled database of 300 cases that fit the diagnostic criteria for PBL. Kaplan-Meier survival curves were constructed. Cox proportional hazards model and Log-rank tests were used to assess the influence of demographic and clinicopathologic factors on overall survival (OS). Results A total of 300 patients with confirmed PBL were identified. The median age was 49. There was a male preponderance with M:F of 2.7. The median duration of symptoms before diagnosis was 1 month. PBL involved the H&amp;N (39%), Lymph nodes (LN) (33%), GI tract (31%), bone marrow (17%), bones (14%), lungs and pleura (10%), skin (9%), spleen (7%), liver (6%), CNS (6%), and testes (2%). Constitutional symptoms were reported in 35%. Stage III/IV accounted for 51% of the cohort. Sixty-two percent were immunosuppressed, 47% due to HIV. While 58% were Kappa restricted, 40% were Lambda, and 2% null. The median OS and DFS of the whole group were 25 and 15 months, respectively. The involvement of BM (p&amp;lt;0.0001), liver (p=0.003), lungs/pleura (p&amp;lt;0.0001), and upper GI tract (0.001) was associated with worse OS. Moreover, CD4&amp;lt;100 (p=0.006), HHV8+ (p=0.02), EBER-negative (p=0.01), LDH&amp;gt;500 (p=0.04), and stage&amp;gt;2 (p&amp;lt;0.0001) were also associated with worse OS. PBL involving the H&amp;N had better OS (p=0.0001). Though CNS involvement, presence of constitutional symptoms, and MYC+ had numerically worse OS, it did not reach statistical significance. Age, sex, light chain restriction, type of immunosuppression, other organ involvement, and other IHC phenotype did not impact OS. Compared to no treatment, chemotherapy and stem cell transplant had incrementally superior median OS (2 vs. 27 vs. NR months, p&amp;lt;0.0001). Frontline intensive chemotherapy yielded better OS than CHOP-like and myeloma regimens in decreasing order (p&amp;lt;0.0001). Patients who attained CR as their best response also had a superior median OS (p&amp;lt;0.0001). Conclusion This study presents clinicopathologic data from the largest pooled cohort of patients with PBL. It identifies the type of organ involvement, CD4 counts, EBER and HHV8 status, LDH levels, stage, type of therapy, and quality of response to treatment as critical determinants of OS.