Large B-cell Lymphoma Cell Research Articles

Autologous stem cell transplantation in T-cell/histiocyte-rich large B-cell lymphoma: EBMT Lymphoma Working Party study

AbstractAlthough broadly used, consolidative autologous hematopoietic stem cell transplantation (auto-HCT) for relapsed/refractory (R/R) T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) has never been specifically investigated. Here, we have analyzed outcomes of auto-HCT for THRLBCL compared with diffuse large cell B-cell lymphoma not otherwise specified (DLBCL). Eligible for this retrospective registry study were adult patients with R/R THRLBCL and DLBCL, respectively, who underwent a first auto-HCT in a salvage-sensitive disease status as assessed by positron emission tomography–computed tomography between 2016 and 2021 and were registered with the European Society for Blood and Marrow Transplantation database. The primary end point was progression-free survival (PFS) 2 years after transplantation. A total of 201 patients with THRLBCL and 5543 with DLBCL were included. There were no significant differences in terms of disease status at HCT, pretreatment lines, and interval from diagnosis to transplant between the cohorts, but patients with THRLBCL were significantly younger, contained a higher proportion of men, and had a better performance status. Compared with DLBCL, THRLBCL was associated with significantly better 2-year PFS (78% vs 59%; P < .001) and overall survival (OS, 81% vs 74%; P = .02) because of a significantly lower 2-year relapse incidence (16% vs 35%; P < .001). On multivariate analysis, favorable relapse risk (hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.31-0.7) and PFS (HR, 0.58; 95% CI, 0.41-0.82) of patients with THRLBCL remained significant, whereas OS benefits (HR, 0.78; 95% CI, 0.54-1.12) did not. These results were validated in a propensity score–matched analysis. These data prove auto-HCT as an effective treatment option for salvage-sensitive R/R THRLBCL.

Abstract 5210: The Prognostic value of serum TK1 protein determinations using AroCell TK210 ELISA in DLBCL patients treated with R CHOP

Abstract Background: Diffuse large-cell B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin’s lymphomas (NHL) that accounts for approximately 25% of the patients. Earlier studies demonstrated the prognostic value of serum thymidine kinase 1 (STK1) activity determinations in different hematological malignancies. To date, the prognostic value of STK1 protein concentration in patients with DLBCL treated with R-CHOP has not been investigated. The purpose of this retrospective study was to determine the value of high TK levels on Overall survival among DLBCL patients treated with R-CHOP as first-line treatment. Materials and Methods: The study included 146 patients diagnosed with DLBCL between 2010 and 2016 from the Uppsala-Umeå Comprehensive Cancer Consortium (U-CAN). All patients included were treated using the standard chemotherapy regimen R-CHOP. Serum samples were collected at the time of diagnosis, during the treatment, 1 year after treatment, and after relapse. Non-infected and apparently healthy persons, matched to the DLBCL patients (57 males and 88 females), served as controls. The TK1 protein levels in all serum samples were determined by using AroCell TK 210 ELISA (AroCell AB, Sweden). The TK1 protein concentration was expressed as μg/L. Results: The TK1 concentrations in sera from DLBCL patients before treatment were significantly higher compared to the concentrations in healthy individuals, median 0.44 μg/L (IQ range 0.22 to 1.06 μg/L) vs. median 0.22 μg/L (IQ range 0.18 to 0.29 μg/L, P&amp;lt;0.00001). Serum TK1 was also significantly higher in patients with more advanced stages (P&amp;lt;0.00001), higher IPI (P&amp;lt;0.00001), and in patients with B-symptoms (P&amp;lt;0.0001). Patients with STK1 protein levels below the cut-off value (0.45 μg/L) had significantly better OS and DFS (P=0.04 and P=0.0006, respectively) compared to patients with STK1 concentration above the cut-off. In multivariate analyses, dichotomized S-TK1 measurements before treatment were found to be significant for the risk of relapse in combination with either aaIPI or IPI (p&amp;lt;0.01). Conclusions: These results confirmed that STK1 concentration correlates with risk factors such as tumor burden, Ann Arbor stage, and IPI. In conclusion, patients with high TK1 concentrations at the time of diagnosis have short overall survival and STK1 concentrations are apparently a prognostic indicator for survival in patients treated with modern chemo-immunotherapy. Citation Format: Kiran Jagarlamudi, Gustaf Hedström, Per Venge, Staffan Eriksson, Daniel Molin, Gunilla Enblad. The Prognostic value of serum TK1 protein determinations using AroCell TK210 ELISA in DLBCL patients treated with R CHOP [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 5210.

Low Dose Total Body Irradiation Improves CD19 CAR-T Expansion, Persistence, and Trafficking, Leading to Enhanced Efficacy in Large B-Cell Lymphoma

Anti-CD19 chimeric antigen receptor T-cell (CART19) is associated with high response rates in large B-cell lymphoma (LBCL). However, a significant subset of patients relapses due to several mechanisms that include poor expansion, lack of CART19 persistence, and immunosuppressive tumor microenvironment. We hypothesized that low dose total body irradiation (LDTBI) may interfere with these mechanisms and thus enhance the efficacy of CART19 cells in LBCL. To test this hypothesis, we utilized a syngeneic mouse model of LBCL, as they are immunocompetent, to best emulate patients treated in clinic. This model involves transplanting BALB/c mice with GFP/Luciferase transduced mouse derived B cell lymphoma (A20) cells and generating murine CART19 (mCART19). We tested mCART19 cytotoxicity in vitro against A20 cells with or without radiation. We found that exposing A20 cells to 1 Gy radiation prior to co-culturing them with mCART19 led to a significant improvement of the mCART19 cytotoxicity (E:T ratio 2.5:1; p=0.029). This is consistent with our in vitro findings for human LBCL cell lines, where weobserved that exposing LBCL cell lines to 1 Gy radiation significantly improved human CART19 cytotoxicity (E:T ratio 2.5:1: OCI-Ly10 cells: p=0.009; SU-DHL-4 cells: p=0.048). Next, we assessed the activity of mCART19 cells in vivo. Animals were lymphodepleted using cyclophosphamide (Cy) administered 24 hours before mCART19 treatment. LDTBI at 1 Gy was delivered 4 hours before mCART19 administration. In addition to evaluating the benefit of single LDTBI prior to mCART19, we also delivered a second dose of LDTBI 9 days after mCART19 treatment. Thus, we evaluated 6 cohorts as follows: (1) Untreated n=4, (2) Cy/LDTBI n=5 (3) Cy/LDTBI/LDTBI n=3, (4) Cy/mCART19 n=5, (5) Cy/LDTBI/mCART19 n=5, (6) Cy/LDTBI/mCART19/LDTBI n=5. Adding LDTBI to Cy provided a minor improvement compared to untreated controls (median overall survival [OS]= 21 days vs 16.5 days; p=0.009). As expected, Cy/mCART19 improved median OS compared to controls (median OS= 35 day; p=0.003). Strikingly, 8/10 of the mice treated with Cy/LDTBI/mCART19 remained in complete remission (CR) at 6 months post-treatment ( p&amp;lt;0.001), Figure 1. Since one dose of LDTBI prior to mCART19 was very effective, adding the second dose of LDTBI did not result in additional survival benefit. Peripheral blood (PB) was monitored regularly, we observed a 2.8-fold increase of mCART19 expansion in the Cy/LDTBI/mCART19 cohort when compared with the Cy/mCART19 cohort ( p&amp;lt;0.001) 9 days post treatment. Importantly, bone marrow aspirates were performed 6 months post treatment in animals that remained alive, demonstrating sustained B-cell aplasia in 7/8 mice (Cy/LDTBI/mCART19 cohorts) which strongly suggests mCART19 persistence. One animal showed B-cell recovery but remained in CR with no relapse suggesting potential cure. Mice that received Cy/mCART19 with no LDTBI showed evidence of B-cell reappearance 7 days prior to overt relapse. Next, we assessed mCART19 trafficking into the tumor tissues by establishing new cohorts of (1) Cy/mCART19 n=4, (2) Cy/LDTBI/ mCART19 n=4 and harvesting tumor-infiltrated spleen and liver 3 days post treatment. Flow cytometry revealed that LDTBI cohort had significant increase in the amount of mCART19 in the spleen and the liver (3.15-fold; p=0.041, and 2-fold; p=0.012, respectively) compared to Cy/mCART19 cohort, suggesting that LDTBI improves mCART19 tumor-trafficking ability. We have previously reported that exposing human LBCL cells to 1Gy radiation in vitro increases expression of FAS when compared to non-irradiated controls and that FAS blockade impairs CART19 cytotoxicity. Hence, we evaluated the expression of FAS in murine LBCL A20 cells harvested from the syngeneic mouse model 3 days post LDTBI. Consistently, we observed 3.1-fold increase in FAS expression, ( p=0.033). In conclusion, our results show a novel and efficacious approach to harnessing LDTBI with CART19. Based on our findings, LDTBI enhances the efficacy of CART19 leading to improved survival in a syngeneic mouse model. Mechanistically, radiation improves CART19 efficacy by boosting CART19 expansion, persistence, trafficking into tumor sites, and upregulation of FAS in tumor cells, pointing to a clinically translatable benefit.

Tocilizumab Administration in CAR-T Cell Associated Cytokine Release Syndrome Induces Hypofibrinogenemia

Introduction Chimeric antigen receptor (CAR)-T cell therapy is considered a therapeutic breakthrough in cancer immunotherapy with high and sustained remission rates. However, it can cause serious side effects such as cytokine release syndrome (CRS). CRS is characterized by systemic hyper-inflammation leading to hypotension, hypoxia, and progressive organ failure. Management of CRS commonly requires administration of the Interleukin-6 receptor antagonist (IL6-RA) tocilizumab. CRS-related coagulopathy is considered the result of disseminated intravascular coagulation (DIC) and concomitant progressive liver dysfunction. Overall, coagulopathy is observed in about every second patient after CAR-T cell therapy with a disproportional rate of hypofibrinogenemia. In this study, we investigated the incidence, dynamics, and possible causes of hypofibrinogenemia after CAR-T cell therapy. Methods We included all patients (n=41) with hematological malignancies receiving CAR-T cell therapies at the University Hospital Regensburg between 2020 and May 2023. All patients were followed up until death or 07/31/2023. Median age was 69 (range: 38-83) years, half of the patients were female and 73% had diffuse large cell B-cell lymphoma. Results 93% of patients developed CRS (12% ≥ grade 3), 71% received tocilizumab and 34% high-dose corticosteroids. While DIC and liver dysfunction almost exclusively occurred in CRS grade 3 or higher, 38% of patients with CRS grade 1 and 90% with CRS grade 2 developed de novo hypofibrinogenemia. Hypofibrinogenemia was severe or life-threatening (CTCEA ≥ grade 3) in 39% of cases and frequently required substitution. Median day of fibrinogen recovery (&amp;gt; lower limit of normal) was day 52 after CAR-T cell therapy. Patients with de novo hypofibrinogenemia initially displayed rising fibrinogen levels alongside development of CRS and rapidly declined in fibrinogen levels shortly after the first administration of tocilizumab. Minimum fibrinogen levels and duration of hypofibrinogenemia further correlated to tocilizumab dosing (r=-0.44 p=0.004 and r=0.7 p&amp;lt;0.001, respectively). Resolution of hypofibrinogenemia was associated to normalization of suppressed C-reactive protein (CRP) after tocilizumab treatment. In contrast, patients with CRS grades 1 and 2 who did not receive tocilizumab (7/13 and 2/20, respectively) had increased fibrinogen levels throughout the course and until resolution of CRS. Logistic regression showed that administration of tocilizumab was the most important, independent risk factor for development of hypofibrinogenemia (OR = 517, p&amp;lt;0.001). Conclusions In summary, hypofibrinogenemia is a frequent complication of CAR-T cell therapy and tocilizumab administration. We conclude that fibrinogen synthesis in CRS is upregulated in an IL-6-dependent acute phase reaction compensating for CRS-induced consumptive coagulopathy. IL-6RA tocilizumab inhibits fibrinogen upregulation and thereby causes protracted hypofibrinogenemia. These observations provide novel insights into the emergence and pathophysiology of hypofibrinogenemia after CAR-T cell therapy and emphasize the need for close fibrinogen monitoring after tocilizumab treatment of CRS.

Linfoma leptomeníngeo primario. Reporte de tres casos y revisión de la literatura

El linfoma leptomeníngeo primario (LLMP) es una entidad con baja frecuencia de presentación, representa del 1% al 2,4% de los linfomas primarios del sistema nervioso central; las variedades histológica más observadas son el linfoma de la zona marginal tipo MALT, el linfoma B de célula grande difuso y el linfoma linfoblástico de células B. La localización y su extensión determinan las manifestaciones clínicas; en radiología se prefieren las imágenes con medios de contraste, ya que tienden a confundirse con meningiomas como la primera impresión diagnóstica y son la cirugía y los estudios de patología los que confirman el diagnóstico. La quimioterapia es la base del tratamiento en esta entidad, la radioterapia se deja como una opción secundaria.&#x0D; El propósito de este trabajo es presentar tres casos clínicos representativos de LLMP y las variantes por imágenes de radiología, la revisión enfocada de la literatura y el tratamiento de esta infrecuente patología.

Baseline volumetric parameters of PET/CT &lt;sup&gt;18&lt;/sup&gt;F-FDG and international prognostic index at patients with diffuse B-cell large cell lymphoma

INTRODUCTION: Metabolic tumor volume (MTV) and Tumor lesion glycolysis (TLG) are used in 18F-fluorodeoxyglucose Positron-Emission Tomography combined with Computed Tomography (18F-FDG PET/CT) as biometric markers in whole tumor. International prognostic index (IPI) has been used during 30 years at patients with diffuse B-cell large cell lymphoma (DLBCL) for prognosis, use MTV and TLG was unknown. Our aims were to determinate the best statistical relationship between MTV, TLG and IPI in patients with DLBCL.OBJECTIVE: Complex study of baseline volumetric parameters PET/CT with 18F-FDG at patients with DLBCL and assessment of their correlation with prognostic groups.MATERIALS AND METHODS: Baseline 18F-FDG PET/CT performed in 31 primary patients with DLBCL and evaluated SUVmax, MTV, TMTV, TLG, TTLG at different involved anatomic zones; correlation between PET biomarkers and prognostic groups of patients.Statistics: The research materials were subjected to statistical processing using the methods of correlation and regression analyses.RESULTS: SUVmax mean level didn’t discerned at patients of low and high-risk groups, but TMTV has been less in favorable prognostic, than in unfavorable groups (152±3.0 sm3 vs 890±178 sm3 p&lt;0,01); the same TTLG (1291±474 g/ml×sm3 vs 7640±2067 g/ml×sm3 , p&lt;0.01) and IMA (6.7±0.7 vs 9.2±0.6; p&lt;0,01). All volumetric parameters have been less at patients with supradiaphragmatic lymph nodes, than infradiaphragmatic lymph nodes and bones too. Significant positive correlation was found between the TMTV u TTLG (p=0.965; p&lt;0,001), between TMTV, TTLG and progressive disease risk (p=0.735; p=0.747; p&lt;0,001). The regression analysis was derived to estimate the connection PET biomarkers and progressive disease risk.DISCUSSION: The 30-year experience of using IPI in assessing the prognosis of patients with DLBCL has shown its insufficient effectiveness in many clinical situations, and the R-IPI prognostic model has been tested on a smaller number of patients and can only be considered additionally. We studied in detail the initial volumetric parameters of patients with DLBCL in different regions of the lesion and their relationship with the level of prognosis according to the IPI criteria. Our data on large values of volumetric parameters in the infradiaphragmatic areas and bones may be related to the worse prognosis in patients with these localizations. Further broader studies of the initial volumetric biomarkers of PET in DLBCL patients will contribute to the development of approximate boundaries of specific volumetric parameters for different tumor localizations.CONCLUSION: The results obtained showed that the baseline volumetric parameters PET/CT at patients with DLBCL have significant connection with prognostic groups of patients and can be additional factors to influence of tactics of therapy.

Novel reconstruction method by mega-prosthesis wrapped with vancomycin-containing cement after resection of malignancies.

To introduce wrapping vancomycin-containing cement around a mega-prosthesis (MP) as a novel method to prevent prosthetic joint infection after reconstruction surgery for malignant bone and soft tissue tumors. Five patients with malignant bone and soft tissue tumors treated at our hospital from April 2009 to December 2019 were included. The average age was 71.4 years. Four males and one female were included. Three patients had a bone tumor, and two had a soft tissue tumor. Three right thighs and two left femurs were affected. These tumors were identified histologically as undifferentiated pleomorphic sarcoma, spindle cell sarcoma, diffuse large cell B-cell lymphoma, metastasis of renal cancer, and metastasis of lung cancer. All patients underwent tumor resection and reconstruction with a MP. In all cases, vancomycin-containing cement (2 g/40 g) was wrapped around the implant at the extension. The average follow-up period was 30.4 months. We surveyed whether infection occurred after surgical treatment. We also investigated the Musculoskeletal Tumor Society score and clinical outcome. We observed no postoperative infection. One case of local recurrence was observed, and a hip dissection was performed. The Musculoskeletal Tumor Society score was 79.26 ± 1.26 (mean ± standard deviation) (range: 76-80.3). Three patients remained disease-free, one survived but with disease, and one died of disease. Wrapping vancomycin-containing cement around the MP may be a useful method of preventing postoperative joint infections.

A Phase1/1b Dose Escalation/Dose Expansion Study of Prgn-3007 Ultracar-T Cells in Patients with Advanced Hematologic and Solid Tumor Malignancies

Background: Receptor tyrosine kinase-like orphan receptor 1 (ROR1) is a promising target for cancer treatment as its expression enhances tumor cell growth and survival, promotes epithelial-mesenchymal transition and metastasis and participates in pro-survival pathways such as PI3-Kinase/AKT, EGFR signaling, and the p38-MAPkinase pathway. ROR1 is undetectable in normal adult tissues, however aberrant expression of ROR1 in malignancies has been detected in B-cell malignancies such as B-cell acute lymphoblastic leukemia (B-ALL), diffuse large cell B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), and mantle cell lymphoma (MCL). Furthermore, upregulated expression has been detected in various solid tumors, including ovarian cancer, breast adenocarcinomas encompassing triple negative breast cancer (TNBC), pancreatic cancer, Ewing's sarcoma and lung adenocarcinoma. The increased expression of ROR1 in hematological and solid tumor malignancies has been associated with tumor proliferation, metastasis and poor clinical outcomes. The autologous UltraCAR-T® platform is designed to overcome the limitations of traditional CAR T which leads to an exhausted T cell phenotype, high manufacturing costs, and treatment delays, using advanced non-viral gene delivery system and a decentralized, overnight manufacturing process. Scientific Rationale: PRGN-3007 is built on Precigen's UltraCAR-T platform and is engineered to simultaneously express a ROR1-specific chimeric antigen receptor (ROR1 CAR); membrane bound interleukin-15 (mbIL15) for enhanced in vivo expansion and persistence; a kill switch for improved safety profile; and a novel mechanism for the intrinsic blockade of programmed cell death protein 1 (PD-1) gene expression. Preclinical studies with PRGN-3007 UltraCAR-T cells showed significant reduction in PD-1 expression with increased ROR1 specific cytotoxicity and inflammatory cytokine production upon co-culture with ROR1+ PD-L1+ hematological and solid tumor cells. Furthermore, PRGN-3007 was selectively and effectively eliminated by the kill switch activator antibody treatment. In vivo, a single administration of PRGN-3007, effectively reduced tumor burden and significantly improved overall survival (p<0.05) of tumor bearing mice compared to Control ROR1 CAR-T in an aggressive xenograft model of mantle cell lymphoma. Blood analyses demonstrated sustained downregulation of PD-1 expression, rapid expansion, long-term persistence, and a predominant central memory phenotype of PRGN-3007 in tumor bearing mice. (Blood (2021) 138 (Supplement 1): 1694.) Study Design: This is a first-in-human, Phase 1/1b dose escalation/dose expansion study to evaluate the safety and effectiveness of PRGN-3007 UltraCAR-T cells in patients with advanced ROR1-postive (ROR1+) hematologic (CLL, MCL, ALL, and DLBCL; Arm 1) and solid tumors (TNBC; Arm 2). Key inclusion criteria include absolute lymphocyte count ≥ 0.2k/µL, KPS > 70, adequate organ function, confirmed expression of ROR1 and: relapsed or refractory CLL; pathologically confirmed ALL B-cell precursor and measurable disease, pathologically confirmed MCL with overexpression of cyclin D1 or presence of t (11;14); pathologically confirmed DLBCL or high grade B-cell lymphoma including transformation from low grade lymphoma; or locally advanced unresectable or metastatic histologically confirmed TNBC with measurable disease as per RECIST 1.1. Study subjects undergo leukapheresis followed by lymphodepletion with either fludarabine 30mg/m2 and cyclophosphamide 500mg/m2 for 3 days (Arm 1) or 60 mg/kg cyclophosphamide for 2 days (Arm 2). The study will enroll in 2 phases: an initial dose escalation phase followed by a dose expansion phase. Up to 4 dose levels are planned in dose escalation phase (Table 1), and the MTD will be determined separately in subjects in the hematologic arm and the solid tumor arm. The MTD for each arm will be expanded independently in the dose expansion phase of the study. All subjects will be followed for adverse events, CAR-T-related toxicities, disease response and PRGN-3007 cell expansion and persistence. In addition, the mechanisms of safety and effectiveness of PRGN-3007 cells will be evaluated with correlative assays of specific immune response pathways. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Real-world use and acceptance of biosimilar rituximab in oncology practice in India

Background: To describe the treatment patterns, patient characteristics and usage pattern of biosimilar rituximab for the treatment of Non-Hodgkin lymphomas (NHL) in India.Methods: This real-world, retrospective, analysis included adult patients receiving biosimilar rituximab between April 2021 and March 2022.Results: A total of 750 patients with NHL who received biosimilar rituximab were included. The most common indications reported in this analysis were diffuse large cell B-cell lymphoma [DLBCL, 64.5% (n=484)], follicular lymphoma, [FL, 23.7% (n=178)], and mantle cell lymphoma [MCL, 5.3% (n=40)]; other subtypes constituted 6.4% of the patients (n=48). The mean age of patients among DLBCL, FL and MCL was 65.5, 55.3 and 57 years, respectively. Across the lymphomas, &gt;90% of the patients received R-chemo as first-line therapy. R-CHOP was the most common regimen across indications.Conclusions: Biosimilar rituximab-based chemotherapy is being adopted in real‑world clinical practice in India for the management of patients with B-cell NHL including DLBCL, FL, MCL and other lymphomas.

ABCL-070 Multicenter Randomized Controlled (Comparative) Open Prospective Study to Evaluate the Efficacy of the R-DA-EPOCH-21 and R-mNHL-BFM-90 ± Autologous Hematopoietic Stem Cell Transplantation Programs in Untreated Patients With Diffuse B-Cell Large Cell Lymphoma With Signs of Poor Prognosis - DLBCL-2015 Protocol

Short-pulse NHL-BFM-90 chemotherapy is highly effective in pediatric aggressive B-cell lymphomas. We modified R3 arm of NHL-BFM-90 program (R-mNHL-BFM-90) for adults under 60 years with high-risk de novo DLBCL and conducted the randomized study compared with R-DA-EPOCH-21 chemotherapy. To evaluate efficacy and toxicity in de novo adult DLBCL patients with 2 or more signs of poor prognosis. Treatment protocol was registered as NCT02842931 at www. gov. Inclusion criteria were newly diagnosed DLBCL, not otherwise specified (NOS), according to WHO, 2008 and 2017 criteria, intermediate and high age-adjusted International Prognostic Index (aaIPI) risk, age 18-60. Response was corresponded by Lugano 2014 criteria. The study design intended randomization for four parallel arms: -6-cycle R-DA-EPOCH-21; - 6-cycle R-DA-EPOCH-21 plus auto-HSCT; - 6-cycle (A-B-A-B-A-B) R-mNHL-BFM-90; - 6-cycle R-mNHL-BFM-90 plus auto-HSCT. If CR wasn't achieved after treatment in every arm additionally 2-cycle R-DHAP chemotherapy were completed before auto-HSCT. A total of 140 patients from 13 Russian clinics were included from February 2015 to June 2021. Randomization was done according "intention-to-treat" as follows: R-DA-EPOCH-21 (35 patients); R-DA-EPOCH-21+auto-HSCT (30 patients); R-mNHL-BFM-90 (37 patients); R-mNHL-BFM-90+auto-HSCT (38 patients). First-step analysis was carried out for 130 patients according "intention-to-treat." In all cases, the final diagnosis was assessed as indolent lymphoma transformation into DLBCL or other "non-DLBCL" lymphomas. Second-step analysis was performed for 116 "proved" de novo DLBCL patients. Evaluation of comparative efficacy was carried out in R-DA-EPOCH-21±auto-HSCT and R-mNHL-BFM-90±auto-HSCT cohorts. Hematological/non-hematological toxicity was acceptable in all groups. However, neutropenic fever and grade 3-4 thrombocytopenia differed statistically significantly (χ2 test, p<0.05) between R-DA-EPOCH-21 and R-mNHL-BFM-90 arms. The value of auto-HSCT will be determined later. De novo DLBCL NOS is potentially a curable disease with no relapses. R-mNHL-BFM-90 program is highly effective in de novo DLBCL NOS adult patients. R-mNHL-BFM-90 therapy toxicity is acceptable. The estimated CR duration probability within 10 months after treatment completion in the high-risk group is 100% in R-mNHL-BFM-90 group compared to 57% in R-DA-EPOCH group (χ2 test, p=0.0047).

Lymphomas in cartilage-hair hypoplasia - A case series of 16 patients reveals advanced stage DLBCL as the most common form.

BackgroundPatients with cartilage-hair hypoplasia (CHH) have an increased risk of malignancy, particularly non-Hodgkin lymphoma and basal cell carcinoma. The characteristics, clinical course, response to therapy and outcome of lymphomas in CHH remains unexplored.MethodsWe assessed clinical features of lymphoma cases among Finnish patients with CHH. Data were collected from the Finnish Cancer Registry, hospital records, the National Medical Databases and Cause-of-Death Registry of Statistics Finland.ResultsAmong the 160 CHH patients, 16 (6 men, 10 women) were diagnosed with lymphoma during 1953-2016. Lymphoma was diagnosed in young adulthood (median age 26.4 years, range from 6.4 to 69.5 years), mostly in advanced stage. The most common lymphoma type was diffuse large cell B-cell lymphoma (DLBCL) (6/16, 38%). Eight patients received chemotherapy (8/16, 50%), and two of them survived. Standard lymphoma chemotherapy regimens were administered in the majority of cases. Altogether, eleven CHH patients died due to lymphomas (11/16, 69%). In almost all surviving lymphoma patients, the diagnosis was made either during routine follow-up or after evaluation for non-specific mild symptoms. Search for CHH-related clinical predictors demonstrated higher prevalence of recurrent respiratory infections, in particular otitis media, and Hirschsprung disease in patients with lymphoma. However, three patients had no clinical signs of immunodeficiency prior to lymphoma diagnosis.ConclusionDLBCL is the most common type of lymphoma in CHH. The outcome is poor probably due to advanced stage of lymphoma at the time of diagnosis. Other CHH-related manifestations poorly predicted lymphoma development, implying that all CHH patients should be regularly screened for malignancy.

Pathological Findings in Gastrointestinal Neoplasms and Polyps in 860 Cats and a Pilot Study on miRNA Analyses.

Simple SummaryIn cats, gastrointestinal masses appear in relevant numbers. Histopathology and immunohistochemistry are needed for a detailed diagnosis but require invasive sampling. Therefore, the improvement of presurgical diagnostics (e.g., biomarkers in serum) is of interest in feline medicine. The present analysis of pathology reports included 679 alimentary lymphomas, 122 carcinomas, 29 spindle cell tumours, 23 polyps and 7 mast cell tumours (MCT). Immunohistochemical characterisation was available from 91 lymphomas, 10 sarcomas and 7 MCTs. Carcinomas and polyps were most commonly found in the large intestine, lymphomas were most commonly found in the stomach and small intestine and MCTs only occurred in the small intestine. In 68%, the submitted lymph nodes were infiltrated by neoplasms, and surgical margins were often not free of tumour cells. The prognostic and therapeutic value of cell size, mitotic count and immunophenotype in lymphomas must be interpreted carefully. A pilot study on miRNA-20b and miRNA-192 concentration in 11 lymphomas, 5 carcinomas and 5 controls was performed. The values of miRNA-20b were found to be up-regulated in samples of all types of cancer, whereas miRNA-192 was up-regulated in carcinomas and B-cell lymphomas only. The diagnostic purpose of miRNAs as potential biomarkers used for the non-invasive diagnosis of intestinal cancer in cats should be further evaluated.Background: Gastrointestinal masses in cats are of clinical relevance, but pathological studies with larger case numbers are lacking. Biomarkers such as miRNA have not yet been investigated in feline intestinal neoplasms. Methods: A retrospective analysis of pathology reports included 860 feline gastrointestinal masses. Immunohistochemistry was performed on 91 lymphomas, 10 sarcomas and 7 mast cell tumours (MCT). Analyses of miRNA-20b and miRNA-192 were performed on 11 lymphomas, 5 carcinomas and 5 control tissues by ddPCR. Results: The pathological diagnosis identified 679 lymphomas, 122 carcinomas, 28 sarcomas, 23 polyps, 7 MCT and 1 leiomyoma. Carcinomas and polyps were most commonly found in the large intestine, lymphomas were most commonly found in the stomach and small intestine and MCT only occurred in the small intestine. Besides the well-described small-cell, mitotic count <2 T-cell lymphomas and the large-cell B-cell lymphomas with a high mitotic count, several variants of lymphomas were identified. The values of miRNA-20b were found to be up-regulated in samples of all types of cancer, whereas miRNA-192 was only up-regulated in carcinomas and B-cell lymphomas. Conclusions: The histopathological and immunohistochemical (sub-)classification of feline intestinal masses confirmed the occurrence of different tumour types, with lymphoma being the most frequent neoplasm. Novel biomarkers such as miRNA-20b and miRNA-192 might have diagnostic potential in feline intestinal neoplasms and should be further investigated.

Determining the risk of developing EBV­-associated lymphoma in HIV-­infected patients

Objective — to increase the efficiency of predicting the development of EBV-associated lymphomas in patients with HIV infection.&#x0D; Materials and methods. In order to improve the prediction of the development of Epstein—Barr associated lymphomas in HIV-infected patients, a comparative analysis of various indicators (clinical-epidemiological, laboratory, serological, etc.) was carried out in 57 HIV patients who had clinical and laboratory confirmation of the presence of co-infection with the Epstein—Barr.Of the 57 patients, manifestations of primary CNS lymphoma were registered in 7 patients (12.3 %), another 1 patient was diagnosed with B-cell large cell lymphoma of the frontal sinus, centroblastic variant (1.8 %), in 1 patient — Burkitt’s lymphoma with lesions of the cervical lymph nodes (1.8 %). To clarify the main trends in the development of lymphomas in patients with HIV and EBV coinfection, a detailed analysis was carried out in two groups: the main group consisted of 9 patients with lymphomas, the remaining 48 patients without detected neoplasms formed the comparison group.&#x0D; Results and discussion. To improve the efficiency of the forecast, multifactorial logistic regressions were constructed, taking into account not only the independent, but also the joint influence of the considered risk factors. To do this, the sum of the scores for each observation was calculated using the corresponding predictive coefficient rank qualification created using the Wald analysis. Based on a multivariate prognostic model, an algorithm was created to determine the risk of developing EBV-associated lymphomas in patients co-infected with EBV and HIV.&#x0D; Conclusions.The created algorithm for determining the risk of developing EBV-associated lymphomas in patients with HIV makes it possible to identify patients with different risks of developing lymphomas under conditions of infection with EBV and HIV, which further creates the possibility for predicting an unfavorable course of HIV infection.The proposed algorithm has a high predictive efficiency, which makes it possible to determine the risk at the individual level and lays the foundation for optimizing the diagnosis of Epstein—Barr virus infection in HIV-infected patients.

Abstract 5438: FCN-589, a novel, potent and selective BTK inhibitor, targets BTK C481S for the treatment of B-cell malignancies

Abstract Bruton’s tyrosine kinase (BTK) is a member of the Tec family of non-receptor tyrosine kinases and plays critical roles in B-cell receptor (BCR) signaling. BTK is often overexpressed in B-cells of patients with hematological malignancies. BTK inhibition blocks BCR signals, prevents B-cell activation and malignant B-cell growth, and induces apoptosis. Early irreversible BTK inhibitors such as ibrutinib, which covalently binds to the cysteine residue (C481) of BTK, are effective against B-cell malignancies and have received approval for various B-cell lymphomas and leukemia including mantle cell lymphoma and chronic lymphocytic leukemia, but their effectiveness is often limited by toxicities from off-target inhibition of the Tec (e.g., ITK/TEC) and EGFR family (e.g., EGFR/HER2/HER4). Acquired resistance mutations in the C481 binding site are known to cause clinical resistance to irreversible BTK inhibitors, which accounts for over half of progression in patients received ibrutinib. There is thus unmet medical need for a novel BTK inhibitor with improved safety profile efficacious against C481 mutation. Here we introduce FCN-589, a novel and orally active next-generation BTK inhibitor. FCN-589 shows potent kinase activities against wild-type (WT) BTK and the most common resistant mutation BTK C481S with single-digit nanomolar IC50 and improved selectivity over clinically significant off-targets such as TRK and ITK compared with nemtabrutinib (MK-1026, ARQ 531), another BTK C481S inhibitor in development. FCN-589 exhibits remarkable anti-proliferating potency against a panel of human B-cell malignancies-derived cancer cell lines. FCN-589 is over 30x more potent against follicular lymphoma cells (DOHH2) and activated B-cell subset of diffuse large B-cell lymphoma (DLBCL) cells (OCI-LY10 and Ri-1), and about 4x more potent against germinal center B-cell like subset of DLBCL cells (SU-DHL-4) compared with ARQ 531. In HEK-293 cell line ectopically expressing WT or BTK C481S, FCN-589 markedly inhibits p-BTK expression with superior activity compared with ARQ 531. Consistently, FCN-589 shows significant and superior anti-tumor activities in mice xenograft models derived from human non-Hodgkin’s lymphomas compared with ARQ 531 and ibrutinib. In non-clinical studies, FCN-589 exhibits good pharmacokinetic (PK) and safety properties. In particular, FCN-589 has longer T1/2 in both rats and dogs, displays improved CYP450 inhibition profile, and is less plasma protein bound compared with ARQ 531. Overall, FCN-589 is a novel next-generation BTK inhibitor targeting WT and BTK C481S. FCN-589 possesses potent in vitro and in vivo anti-cancer activities with better selectivity against clinically significant off-targets and exhibits favorable PK and safety profiles compared with ARQ 531. FCN-589 has potential to be a more effective and safer option for patients with B-cell malignancies. Citation Format: Shu Lin, Haohan Tan, Qihong Liu, Yunling Wang, Bin Liu, Zhifu Li, Zhifang Chen, Xianlong Wang, Xingdong Zhao, Lihua Jiang, Xilei Wang, Tao Cheng, Jiashu Zhou, Weibo Wang. FCN-589, a novel, potent and selective BTK inhibitor, targets BTK C481S for the treatment of B-cell malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5438.

Abstract 3271: BRD4 inhibition enhances the acalabrutinib tumor response by modulating PAX5 and interferon signaling in ABC-DLBCL

Abstract AZD5153 is a bivalent bromodomain and extraterminal (BET) inhibitor that simultaneously engages the two bromodomains of bromodomain-containing protein 4 (BRD4). Here, we initially tested AZD5153 in combination with acalabrutinib, a Bruton tyrosine kinase (BTK) inhibitor, in a panel of diffuse large B-cell lymphoma (DLBCL) cell lines. The ABC type DLBCL cells responded to the AZD5153 and acalabrutinib combination at lower drug concentrations compared to other DLBCL cell lines. Many of these lower concentrations were below the clinical equivalent dose for each drug. Similar results were achieved in DLBCL patient-derived xenografts, with most ABC-DLBCL tumors having more growth inhibition than the other B-cell lymphoma tumors after combination dosing at fixed concentrations. To delineate the mechanism of ABC-subtype preference for combination therapy, we performed RNA sequencing on ABC-DLBCL tumor samples treated with AZD5153, acalabrutinib, and the combination of AZD5153 and acalabrutinib. Pathway meta-analyses identified significant alterations of PAX5 signaling and interferon pathways in combination-treated tumors compared to monotherapy-treated samples. PAX5 is a key gene for B-cell activation and is associated with lymphoma pathogenesis. Protein levels of PAX5 and corresponding downstream transcription targets were also decreased by the combination of AZD5153 and acalabrutinib in ABC-DLBCL cell lines. In addition, STAT proteins related to PAX5 activation, the alternative RelB-NFκB pathway, and toll-like receptors in the interferon type I pathway were also modulated at the protein level by this drug combination in ABC-DLBCL cell lines. We hypothesized the AZD5153 and acalabrutinib combination induces changes to interferon signaling that impacts PAX5 activation. This mechanism is supported by evidence of AZD5153 and acalabrutinib combination-induced downregulation of interferons alpha and beta, as well as interferon gamma and IP-10 in vivo. In summary, our results demonstrate AZD5153 enhances the efficacy of acalabrutinib, and our in vitro data suggest adding AZD5153 to acalabrutinib concentrations much lower than the clinical equivalent dose results in a similar biomarker response. We show that this drug combination attenuates interferon signaling, which supports the mechanism of AZD5153 and acalabrutinib inhibiting PAX5 signaling in ABC-DLBCL. Citation Format: Derek B. Oien, Samanta Sharma, Ye Xu, Maureen Hattersley, Michelle DuPont, Kathleen Burke, Steven W. Criscione, Laura Prickett, Jingwen Zhang, Ho Man Chan, Lisa Drew, Yi Yao. BRD4 inhibition enhances the acalabrutinib tumor response by modulating PAX5 and interferon signaling in ABC-DLBCL [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3271.

Abstract 3939: Preclinical development of embryonic ectoderm development (EED) inhibitor APG-5918/EEDi-5273 for cancer therapy

Abstract Three core components constitute the polycomb repressive complex 2 (PRC2), a multiprotein complex that catalyzes methylation of histone H3 at lysine 27 (H3K27): (1) enhancer of zeste homolog 2 (EZH2), (2) EED, and (3) suppressor of zeste 12 protein homolog (SUZ12). Dysregulated function of PRC2 is implicated in the development of various cancer types. With regulatory approval of EZH2 inhibitor tazemetostat, a potentially effective successful cancer therapeutic strategy is now available for patients with epitheloid sarcoma and relapsed or refractory follicular lymphoma. However, EZH2 inhibitor activity might be reduced because of acquired resistance through secondary mutations in EZH2 or its inability to inhibit paralogs of EZH2 (including EZH1). Because binding of EED with trimethylated H3K27 (H3K27me3) is required to activate methyltransferase activity of EZH2, allosterically targeting EED is emerging as a novel approach to inhibit PRC2 (Qi et al, Nat Chem Biol 2017). APG-5918/EEDi-5273 is a well-documented, investigational, novel, bioactive, and potent EED inhibitor (Rej et al, JMC 2021). The aim of this study was to further characterize the anticancer therapeutic activity of APG-5918 in the preclinical setting. APG-5918/EEDi-5273 showed high-affinity binding to EED protein in a biochemical assay (IC50 = 1.2 nM). It also exerted potent antiproliferative activity in several EZH2 mutant (EZH2mut) diffuse large B-cell lymphoma (DLBCL) cell lines, with IC50 values in the nanomolar range and inhibitory effects that were approximately 5 times lower than those with tazemetostat. In a mouse xenograft model derived from EZH2mut KARPAS-422 DLBCL cells, single-agent APG-5918 conferred potent and dose-dependent antitumor activity, resulting in durable complete tumor regression that correlated with inhibition of H3K27me3, induction of PRC2 target genes, and drug exposure in tumors. In summary, our results provide scientific rationale for the clinical development of APG-5918/EEDi-5273 in EZH2mut lymphomas and, potentially, other hematologic malignancies and solid tumors. Citation Format: Saijie Zhu, Douglas D. Fang, Qiang Li, Dongmei Yang, Shoulai Gu, Shaomeng Wang, Dajun Yang, Yifan Zhai. Preclinical development of embryonic ectoderm development (EED) inhibitor APG-5918/EEDi-5273 for cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3939.

Abstract 6303: Activity and tolerability of combination of venetoclax with the Aurora kinase B Inhibitor AZD2811 in preclinical diffuse large B-cell lymphoma models

Abstract Diffuse large B-cell lymphoma (DLBCL) is an aggressive type of non-Hodgkin lymphoma (NHL) and the most common form of adult lymphoma. Despite efforts to develop new therapies, the standard of care for DLBCL remains chemotherapy based. The current standard of care is comprised of a regimen of 4 drugs (cyclophosphamide, doxorubicin, vincristine, and prednisone) combined with immunotherapy using a chimeric mAb against the protein CD20 (rituximab), R-CHOP. Unfortunately only 50 to 60% of patients with DLBCL achieve and maintain complete remission after first-line therapy and 40 to 50 % relapse or have refractory disease. In addition, the average age at the time of diagnosis for DLBCL is 64 which makes intensive chemotherapy challenging. Therefore, the development of new treatment options is critical. We explored preclinical activity of AZD2811 nanoparticle, a potent and selective inhibitor of Aurora B kinase combined with venetoclax, an inhibitor of BCL2 currently used as standard of care in treatment of Haematological cancers, in B-Cell non-Hodgkin lymphoma models. Twenty five B-cell NHL cell lines including 11 Diffuse Large B-cell Lymphoma (DLBCL) cell lines were exposed to a 7 x 7 matrix of AZD2811 and venetoclax for 72 hrs. Cell viability was assessed using Celltiter-glo. Strong combination activity (HSA &amp;gt; 0.1 and combination Emax &amp;gt; 0.5) was observed in 6 cell lines including 2 DLBCL cell lines (WSU-DLCL2 and KARPAS_422). Moreover, pre-treatment with pan caspase inhibitor Q-VD-OPH, increased cell viability in cells treated with the combination. Next we explored the significant gene expression and mutation biomarkers (effect size &amp;gt; 1, p &amp;lt; 0.05) for this combination associated with Bliss and combination Emax in B-cell NHL cell lines. We found downregulation of 4 genes (FLT4, TIE1, PRKN) and mutations in 2 genes (EP300 and PTEN) to be associated with Bliss score and upregulation of one gene (FGR) associated with combination Emax. In vivo, antitumor activity of AZD2811 combined with venetoclax was assessed in mice bearing WSU-DLCL2luc xenografts. Once weekly intravenous administration of 25 mg/kg AZD2811 resulted in a statistically significant tumor growth inhibition (TGI) of 74%, while daily oral gavage of 100 mg/kg venetoclax resulted in 49% TGI but failed to reach statistical significance. While both monotherapies were unable to prevent progressive tumor growth, a combination dosing regimen of AZD2811 and venetoclax drove progressive tumor regression resulting in statistically significant complete regression (98% regression) by the third week of dosing. These results suggest combining AZD2811 with venetoclax has potential to be active in DLBCL patients. Citation Format: Azadeh Cheraghchi-Bashi, Brandon Willis, Kevin. Mongeon, Jacob Gordon, Krishna Bulusu, Elizabeth Coker, Patricia Jaaks, Mathew Garnett, Jerome Mettetal. Activity and tolerability of combination of venetoclax with the Aurora kinase B Inhibitor AZD2811 in preclinical diffuse large B-cell lymphoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6303.

Primary cardiac diffuse large B-cell lymphoma presenting with cardiac tamponade: a case report

BackgroundPrimary cardiac tumours are extremely rare with an autopsy incidence of 0.05%. They can present with a variety of symptoms, including life-threatening arrhythmia and cardiac tamponade. In this case report, we focus on the diagnostic process and management of a primary cardiac lymphoma (PCL) presenting with cardiac tamponade.Case summaryWe report on a 71-year-old male presenting with a large pericardial effusion, tamponade, and a mass in the right atrioventricular groove. Multimodality imaging was performed, including transthoracic echocardiography, computed tomography, magnetic resonance imaging, positron emission tomography, and computed tomography-guided transthoracic biopsy. The final diagnosis of a double-hit diffuse large-cell B-cell lymphoma was made, for which treatment consisting of a combination of chemotherapy and immunotherapy was initiated. Low-dose colchicine was also added to the treatment.DiscussionPrimary cardiac lymphoma remains a very rare diagnosis and this case highlights the need for multimodality imaging and imaging-guided biopsy to differentiate cardiac masses. First-line treatment for PCL remains a combination of chemotherapy with immunotherapy, with the addition of low-dose colchicine to prevent recurrence of malignant pericardial effusion.

Methodological Aspects of Measuring Metabolic Tumor Volume in Patients with Diffuse B-Cell Large Cell Lymphoma by PET/CT with 18F-FDG

Introduction: Metabolic Tumor Volume (MTV) and Total Tumor Lesion Glycolysis (TLG) are used in 18F-fluorodeoxyglucose Positron-Emission Tomography combined with Computed Tomography (18F-FDG PET/CT) as functional markers, indicating tracer uptake in whole tumor. MTV and TLG are not yet engaged in clinical practice, because volume measurement accuracy depends on the selected measurement method, and optimal MTV and TLG segmentation is not established.Purpose: Assessment of accuracy of metabolic tumor volume measurement ways, using 18F-FDG PET/CT in patients with Diffuse Large B-Cell Lymphoma (DLBCL).Material and methods: Baseline 18F-FDG PET/CT performed in 21 patients with DLBCL. Tumor Volume (TV), measured on contrast enhanced CT (CTTV), considered as reference. While measuring MTV, we aimed to achieve a 1:1 ratio between CTTV and MTV. If anatomical and metabolic tumor contours matched, MTV was considered true (MTVtrue). Overall MTV and TLG measurements are 254. Tumor contouring, using relative thresholds, was made around Standardized Uptake Value (SUVmax) of tracer in tumor and intact liver.Results: On CT, the size of the lesions varied from 24 to 241 mm, M = 103.4±62.3, Me = 93 (48.5–155.5). In 15 (71.4 %) foci, hypodense areas of necrosis were determined. PET imaging revealed high tracer uptake in all foci of varying degrees of intensity. SUVmax values in tumors ranged from 5.8 to 30.5, Me = 20.4 (17.3–23.2). No significant correlation was found between the size of the foci and SUVmax (ρ = 0.17, p = 0.4744). The best accuracy in measuring MTV was observed when several thresholds were applied: VOIPERCIST, VOI2.5, VOIauto-contour, as well as VOI10 %, VOI15 % and VOI20 %. The optimal absolute threshold values were SUV values in the range from 2 to 3, and relative values in the range from 10 % to 20 % of the SUVmax in the tumor. MTV underestimation was more often determined using relative cut-off indices in the range of25–50 % and SUV thresholds ≥ 5.3.Conclusion: The results obtained showed that the use of a single threshold value for MTV segmentation in patients with DLBCL is not advisable. The choice of the MTV measurement method should be carried out individually for each lesion, taking into account its shape, size and structure, as well as the intensity and uniformity of tracer uptake in the tumor and adjacent anatomical structures.

Safety and Anti-Tumor Activity of Plamotamab (XmAb13676), an Anti-CD20 x Anti-CD3 Bispecific Antibody, in Subjects with Relapsed/Refractory Non-Hodgkin's Lymphoma

Safety and Anti-Tumor Activity of Plamotamab (XmAb13676), an Anti-CD20 x Anti-CD3 Bispecific Antibody, in Subjects with Relapsed/Refractory Non-Hodgkin's Lymphoma