Subtype Of Diffuse Large B-cell Lymphoma Research Articles

Case report: Surgical repair of a large tracheo-esophageal fistula in a patient with post-transplant esophageal lymphoproliferative disorder

Introduction and importanceThe management of large malignant tracheo-esophageal fistulas (TEF) is not standardized. Herein, we report a case with a malignant TEF associated with esophageal post-transplant lymphoproliferative disorder (PTLD) for whom we successfully performed a surgical repair. This contributes to the knowledge on how to treat large acquired malignant TEFs.Case presentationA 69-year old male presented with a one-week history of fever, productive cough and bilateral coarse crackles. In addition, he described a weight loss of 10 kg during the past three months. The patient's history included a kidney transplantation twenty years ago. Esophagogastroduodenoscopy with a biopsy of the esophagus was performed nine days before. Histopathology showed a PTLD of diffuse large B-cell lymphoma subtype. Subsequent diagnostics revealed a progressive TEF (approx. 2.0 × 1.5 cm) 3.0 cm above the carina. PET-CT scan showed an esophagus with slight tracer uptake in the middle third (approx. 11.5 cm length, SUV max 7.4). After decision against stenting, transthoracic subtotal esophagectomy with closure of the tracheal mouth of the fistula by a pedicled flap was performed. PTLD was treated with prednisone and rituximab. Tumor progression (brain metastasis) led to death 95 days after surgery.Clinical discussionThe treatment of a malignant TEF is complex and personalized while both the consequences of the esophago-tracheal connection and those of the underlying responsible diagnosis have to be considered concurrently. In this case, we considered surgery as the best treatment option due to a relatively good prognosis of the underlying diagnosis (PTLD) and a large fistula. Esophageal or dual stenting, the treatment of choice for small malignant TEF, would have been associated with a high risk of failure due to the wide trachea, extensively dilated esophagus, proximal location and large diameter of the fistula.ConclusionSurgery can be considered for patients with a large acquired malignant TEF and positive long-term prognosis of the underlying diagnosis. Due to the complexity of TEF management, immediate pre-operative multidisciplinary discussion is advised.

Next-Generation Sequencing Highlights of Diffuse Large B-cell Lymphoma in a Tertiary Care Hospital in North India.

Introduction: Next-generation sequencing (NGS) elucidates the diffuse large B-cell lymphoma (DLBCL) genetic characteristics by finding recurrent and novel somatic mutations. This observational study attempted to create an NGS panel with a focus on identifying novel somatic mutations which could have potential clinical and therapeutic implications. This panel was created to look for mutations in 133 genes chosen on basis of a literature review and it was used to sequence the tumor DNA of 20 DLBCL patients after a centralized histopathologic review.Methods: The study included 20 patients having DLBCL. The quality and quantity of tumor cells were accessed by H&E staining and correlated with histopathology and Immunohistochemistry (IHC) status. Patients were grouped as ABC (activated B-cell), PMBL (primary mediastinal large B-cell lymphoma), and other or unclassified subtypes. The lymphoma panel of 133 was designed on targeted sequencing of multiple genes for the coding regions through NGS. The libraries were prepared and sequenced using the Illumina platform. The alignment of obtained sequences was performed using Burrows-Wheeler Aligner and identification of somatic mutations was done using LoFreq (version 2) variant caller. The mutations were annotated using an annotation pipeline (VariMAT). Previously published literature and databases were used for the annotation of clinically relevant mutations. The common variants were filtered for reporting based on the presence in various population databases (1000G, ExAC, EVS, 1000Japanese, dbSNP, UK10K, MedVarDb). A custom read-depth-based algorithm was used to determine CNV (Copy Number Variants) from targeted sequencing experiments. Rare CNVs were detected using a comparison of the test data read-depths with the matched reference dataset. Reportable mutations were prioritized and prepared based on AMP-ASCO-CAP (Association for Molecular Pathology-American Society of Clinical Oncology-College of American Pathologists), WHO guidelines, and also based on annotation metrics from OncoMD (a knowledge base of genomic alterations).Results: The informativity of the panel was 95 percent. NOTCH 1 was the most frequently mutated gene in 16.1% of patients followed by 12.9% who had ARID1A mutations. MYD88 and TP53 mutations were detected in 9.6% of the patient while 6.4% of patients had CSF3R mutations. NOTCH 1 and TP 53 are the most frequently reported gene in the middle age group (40-60). Mutation in MYD88 is reported in every age group. MYD88 (51%) is the most common mutation in ABC subtypes of DLBCL, followed by NOTCH 1 (44%) and SOCS 1 (33%) according to our findings. NOTCH 1 mutations are frequent in ABC and PMBL subtypes. Closer investigation reveals missense mutation is the most frequent mutation observed in the total cohort targeting 68.4% followed by frameshift deletion reported in 26.3%. Six novel variants have been discovered in this study.Conclusions: This study demonstrates the high yield of information in DLBCL using the NGS Lymphoma panel. Results also highlight the molecular heterogeneity of DLBCL subtypes which indicates the need for further studies to make the results of the NGS more clinically relevant.

Immunogenomic-Based Analysis of Hierarchical Clustering of Diffuse Large Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL) is one of the most usual types of adult lymphoma with heterogeneousness in histological morphology, prognosis, and clinical indications. Prior to this, several studies were carried out to determine the DLBCL subtype based on the analysis of the genome profile. However, classification based on assessment of genes related to the immune system has limited clinical significance for DLBCL. We systematically explored the DLBCL gene expression dataset and provided publicly available clinical information on patients with GEO. In this research, 928 DLBCL samples were applied, and we calculated 29 immune-related genomes' enrichment levels in each sample and stratified them into high immunity (Immunity_H, n = 135, 28.7%), moderate immunity (Immunity_M, n = 135, 28.7%), and low immunity (Immunity_L, n = 12, 2.6%) that was based on ssGSEA score. The ESTIMATE algorithm was used to calculate stromal scores (range 586.88 to 1982.43), immune scores, estimated scores (range 2,618.2 to 8,098.14), and tumor purity (range 0.216 to 0.976). All of them were significantly correlated with immune subtypes (Kruskal-Wallis test, p < 0.001). At the same time, the correlation of related genes was analyzed by immunohistochemistry staining. In addition, DLBCL cells were cultured in transfected and in vitro with siRNA to verify correlation analysis and gene expression. Finally, human peripheral blood lymphocytes were incubated with DLBCL cells and stained. Flow cytometry was applied to analyze genes' influence on immune function. By analysis, immune checkpoint and HLA gene expression levels were higher in the Immunity_H group (Kruskal-Wallis test, p < 0.05). The levels of Tfhs (follicular helper T cells), monocytes, CD8+ T cells, M1 macrophages, M2 macrophages, and CD4+ memory-activated T cells were the most excellent in Immunity_H, and the total survival rate was higher in the Immunity_L. Through analysis, IRF4 (MUM1) was identified by us as immunotherapeutic target and a potential prognostic marker for DLBCL, which was made sure by using molecular biology experimentations. To conclude, immunosignature made a connection between DLBCL subtypes playing a position in DLBCL prognostic stratification. Immunocharacteristics-related DLBCL subtypes' construction predicts expected patient results and supplies conceivable immunotherapy candida.

The Methylation of the p53 Targets the Genes MIR-203, MIR-129-2, MIR-34A and MIR-34B/C in the Tumor Tissue of Diffuse Large B-Cell Lymphoma.

The regulation of oncogenes by microRNA is a focus of medical research. hsa-miR-203, hsa-mir-129, hsa-miR-34a, hsa-miR-34b and hsa-miR-34c are oncosuppressive microRNAs that mediate the antitumor activity of p53. We seek to evaluate the frequencies, co-occurrence and clinical significance of the methylation of the MIR-203, MIR-129-2, MIR-34A and MIR-34B/C genes in the tumor tissue of diffuse large B-cell lymphoma (DLBCL). The methylation was assessed in 73 samples of DLBCL and in 11 samples of lymph nodes of reactive follicular hyperplasia by Methyl-Specific Polymerase Chain Reaction (MS-PCR) and Methylation-Sensitive High-Resolution-Melting (MS-HRM) methods. All four studied genes were not methylated in the tissue of reactive lymphatic nodes. The methylation frequencies of the MIR-129-2, MIR-203, MIR-34A and MIR-34B/C genes in lymphoma tissue were 67%, 66%, 27% and 62%, respectively. Co-occurrence of MIR-203, MIR-129-2 and MIR-34B/C genes methylation, as well as the methylation of MIR-34B/C and MIR-34A pair genes were detected. The MIR-34A gene methylation was associated with increased International Prognostic Index (IPI) (p = 0.002), whereas the MIR-34B/C (p = 0.026) and MIR-203 (p = 0.011) genes’ methylation was connected with Ki-67 expression level in tumor tissue at more than 45%. We found an increasing frequency of detection of MIR-34A gene methylation in the group of patients with the Germinal-Center B-cell like (GCB-like) subtype of DLBCL (p = 0.046). There was a trend towards a decrease in the remission frequency after the first line of therapy (p = 0.060) and deterioration in overall survival (OS) (p = 0.162) in patients with DLBCL with methylation of the MIR-34A promoter. The methylation of the MIR-34A, MIR-34B/C, MIR-129-2 and MIR-203 genes in DLBCL is tumor-specific and occurs in combination. The methylation of the studied genes may be a potential differential diagnostic biomarker to distinguish between lymphoma and reactive lymph nodes, while its independent predictive value has not been confirmed yet.

Value of the prognostic nutritional index (PNI) in patients with newly diagnosed, CD5-positive diffuse large B-cell lymphoma: A multicenter retrospective study of the Huaihai Lymphoma Working Group.

CD5-positive diffuse large B-cell lymphoma (DLBCL) is a clinically rare subtype of DLBCL with aggressive clinical manifestations and a poor prognosis. It has been demonstrated that the prognostic nutritional index (PNI), an indicator of nutritional status and systemic inflammation, is a significant prognostic factor for several types of lymphoma. The objective of this multicenter retrospective study was to explore the prognostic value of the PNI in patients with CD5-positive DLBCL. In total, 207 patients with CD5-positive DLBCL were recruited from 11 centers of the Huaihai Lymphoma Working Group. Maximally selected rank statistics analysis was used to identify optimal cutoff points for the PNI. A Cox proportional hazards model was used for univariable and multivariable analyses. Kaplan-Meier curves were used to calculate survival rates and draw survival curves, and the log-rank test was used to compare differences between groups. The median age at diagnosis was 61 years, and the 5-year overall survival rate was 47.5%. According to the maximally selected rank statistics analysis, a score of 49.7 was the optimal cutoff point for the PNI. Subgroup analysis showed that the PNI could re-stratify patients in BCL-2-negative, MYC-negative, high-intermediate-risk and high-risk International Prognostic Index, BCL-6-positive and BCL-6-negative, high Ki-67 score (≥0.9), Ann Arbor stage III/IV, Eastern Cooperative Oncology Group performance status ≥2, and germinal center B subgroups. Multivariable analysis revealed that PNI, age, Eastern Cooperative Oncology Group performance status, albumin level, and red blood cell count were independent prognostic factors for CD5-positive DLBCL. The PNI was a significant prognostic indicator for CD5-positive DLBCL and was able to re-stratify the prognosis for clinicopathologic subgroups of patients with CD5-positive DLBCL.

Integrative genome‐wide chromatin accessibility and transcriptome profiling of diffuse large B‐cell lymphoma

Integrative genome‐wide chromatin accessibility and transcriptome profiling of diffuse large B‐cell lymphoma

Immunohistochemical subtyping of diffuse large B-cell lymphoma into germinal center B-cell and activated B-cell subtype, along with correlation of the subtypes with extranodal involvement, serum lactate dehydrogenase, and positron emission tomography scan-based response assessment to chemotherapy

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma in Indian population and is divided into the prognostically important subtypes, germinal center B-cell (GCB) and activated B-cell-like (ABC), using immunohistochemistry-based algorithm. The present study aims to evaluate the influence of immunohistochemical derived DLBCL subtype, GCB or ABC on prognostically significant variables - extranodal involvement and serum lactate dehydrogenase (LDH) level at presentation, and response to chemotherapy assessed on pre- and posttreatment fluorodeoxyglucose-positron emission tomography study. This was a retro-prospective, 2-year observational study at a tertiary health-care center, New Delhi. The study population includes a total 236 cases of DLBCL. According to the Hans algorithm, DLBCL cases were allocated to the GCB and ABC subgroups. For comparison of mean values, independent t-test and analysis of variance were used. For this purpose, we used SPSS 20.0 software. P < 0.05 was considered as statistically significant. Ninety-eight patients (41.5%) had GCB immunophenotype and 138 patients (58.5%) were ABC. A significant difference was observed between mean baseline level of LDH between GCB and ABC subtypes (P < 0.05). The proportion of cases with extranodal involvement was comparatively higher in ABC subtype (P < 0.05). Association between response to chemotherapy with DLBCL immunophenotypes was found to be highly significant (P < 0.00). The response rates were much better in GCB subtype. The mean baseline level of LDH is significantly higher in ABC subtype. The proportion of cases with extranodal involvement was comparatively higher in ABC and shows poor response to chemotherapy as compared to GCB. Baseline LDH level was found to be important prognostic marker in the DLBCL.

Pathway importance by graph convolutional network and Shapley additive explanations in gene expression phenotype of diffuse large B-cell lymphoma.

Deep learning techniques have recently been applied to analyze associations between gene expression data and disease phenotypes. However, there are concerns regarding the black box problem: it is difficult to interpret why the prediction results are obtained using deep learning models from model parameters. New methods have been proposed for interpreting deep learning model predictions but have not been applied to genetics. In this study, we demonstrated that applying SHapley Additive exPlanations (SHAP) to a deep learning model using graph convolutions of genetic pathways can provide pathway-level feature importance for classification prediction of diffuse large B-cell lymphoma (DLBCL) gene expression subtypes. Using Kyoto Encyclopedia of Genes and Genomes pathways, a graph convolutional network (GCN) model was implemented to construct graphs with nodes and edges. DLBCL datasets, including microarray gene expression data and clinical information on subtypes (germinal center B-cell-like type and activated B-cell-like type), were retrieved from the Gene Expression Omnibus to evaluate the model. The GCN model showed an accuracy of 0.914, precision of 0.948, recall of 0.868, and F1 score of 0.906 in analysis of the classification performance for the test datasets. The pathways with high feature importance by SHAP included highly enriched pathways in the gene set enrichment analysis. Moreover, a logistic regression model with explanatory variables of genes in pathways with high feature importance showed good performance in predicting DLBCL subtypes. In conclusion, our GCN model for classifying DLBCL subtypes is useful for interpreting important regulatory pathways that contribute to the prediction.

P650: A FIRST-IN-HUMAN PHASE 1 TRIAL OF NX-5948, AN ORAL BTK DEGRADER, IN PATIENTS WITH RELAPSED AND REFRACTORY B-CELL MALIGNANCIES

Background: Bruton’s tyrosine kinase (BTK) is a key component of the B-cell receptor (BCR) signaling pathway and chronic activation of BTK-mediated BCR signaling is a hallmark of many B-cell malignancies. BTK-targeted therapy has been shown to be safe and effective in a variety of B-cell lymphomas, including chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), mantle cell lymphoma (MCL), marginal zone lymphoma (MZL), and Waldenström macroglobulinemia (WM). However, BTK inhibitor (BTKi) resistant disease remains a clinical challenge with limited options for salvage therapy and overall poor patient outcomes. BTK degradation may be effective in patients who have developed resistance to BTKi or in B-cell indications where treatment with BTKi has been less effective. NX-5948 is an oral, small molecule that induces BTK degradation through the recruitment of cereblon, an adaptor protein of the E3 ubiquitin ligase complex, and does not induce degradation of other cereblon neosubstrates. NX-5948 degrades both wild type BTK and BTKi resistant mutants (C481) and inhibits ibrutinib-resistant tumor cell line growth at concentrations where ibrutinib and acalabrutinib are inactive. NX-5948 potently inhibits tumor growth in xenograft models that contain either wild type BTK or BTKi-resistant mutations. Further, NX-5948 crosses the blood-brain barrier, thus positioning it as a therapeutic agent in patients with primary central nervous system lymphoma (PCNSL) and other lymphomas that have CNS involvement. Aims: The primary objectives are to evaluate safety and tolerability, determine the maximum tolerated dose (MTD; Phase 1a only), and the early clinical activity in each expansion cohort (Phase 1b only) of NX-5948 in patients with relapsed and refractory B-cell malignancies. Methods: NX-5948-301 is a first-in-human, dose escalation (Phase 1a) and cohort expansion (Phase 1b) study designed to evaluate the safety, tolerability, and preliminary efficacy of NX-5948 in adult patients with relapsed and refractory B-cell malignancies. NX-5948 will be given orally daily and dose escalation will proceed using a standard 3 + 3 design. There will be up to 5 expansion cohorts in Phase 1b composed of patients with the following tumor types: (a) CLL/SLL with a C481 mutation; (b) CLL/SLL without a C481 mutation; (c) aggressive subtypes diffuse large B-cell lymphoma (DLBCL) and MCL; (d) indolent subtypes FL, MZL, and WM; and (e) primary/secondary CNS lymphoma. Other key eligibility criteria include 2 or more prior lines of therapy (only 1 prior for WM and PCNSL); measurable disease; and an Eastern Cooperative Oncology Group performance status of 0 or 1. Up to 130 patients (30 in Phase 1a, 100 in Phase 1b) will be enrolled and treated until disease progression or unacceptable toxicity. Results: Enrollment in this study has begun in Europe. Summary/Conclusion: Accrual is ongoing. Clinical trial information: NCT05131022.

P1216: ZANUBRUTINIB PLUS R-CHOP(RI-CHOP) AS THE TREATMENT FOR DOUBLE EXPRESSION OF MYC/BCL2 IN PATIENTS WITH DIFFUSED LARGE B-CELL LYMPHOMA

Background: Diffuse large B cell lymphoma (DLBCL) with double expression of MYC and BCL2 proteins (DE-DLBCL) is an aggressive disease. The incidence of double expressor status in DLBCL was 20～30%.BCL2 overexpression was more frequent in Chinese compared with Western cases in the non-GCB subgroup. MYC/BCL2 co-expression is an adverse predictive factor for response to chemotherapy regimens, and associateswith a significantly lower probability of complete remission. Aims: To investigate a prognostic significance of MYC/BCL2 double expression in DLBCL patients treated with intensive chemotherapy RI-CHOP, we conducted this single-arm prospective study. Methods: We enrolled 31 patients aged 18 to 70 years old with double expressor status in DLBCL (DE-DLBCL) underwent modified protocol of intensive chemotherapy – zanubrutinib plus R-CHOP(RI-CHOP) in West China Hospital between 2020 and 2021 years were included in the study. We used the cutoff values of protein co-expression are 50% for BCL2 and 40% for MYC. This study excluded DE-DLBCL With c-MYC 、BCL2 or BCL6 rearrangements and Central nervous system involvement. Oral zanubrutinib was given continuously (160mg twice daily) from Day 1. Patients were administered intravenously rituximab, cyclophosphamide doxorubicin, vincristine,and prednisone. All patients were recommended to receive 6 cycles of RI-CHOP. Patients received oral ciprofloxacin (500 mg daily on Day 3-13) to prevent bacterial infection.CT/PET-CT scans were conducted to assess efficacy in 2,4,6 cycles. Four cycles of intrathecal methotrexate administration (15 mg) were performed for patients with a high CNS-IPI score and/or lymphoma-risk factors warranting CNS prophylaxis.The primary endpoint was overall response rate (ORR), after mid-term and 6 cycles. The secondary endpoint was complete response ratio (CR) and adverse events (AE). AEs were graded according to CTCAE (version 5.0). Results: 31 treatment-naïve DE-DLBCL patients diagnosed in West China hospital were enrolled in this cohort between April 2020 and December 2021. The median age of patients was 56 years old, all patients had ECOG performance ≤2.Germinal center B cell-like DLBCL (GCB) and non-GCB subtypes were found in (5/31) and (26/31), respectively. Extranodal involvement was found in 17 patients (54.8%), which the sites of extranodal involvement were the gastrointestine (3/31), bone marrow (5/31), nasal cavity (5/31),breast(2/31),testicle (1/31), renal(1/31),Vertebral body(1/31),Uterine appendage(1/31). 7 patients were classified as high-intermediate and high-risk group according to CNS-IPI. At data cutoff (December, 2021), the median follow-up was 10.5 months (2.2-19.1months) with all patients have completed at least 2 cycles. Patients received a median of 5 cycles (range 2–6 cycles),and midterm assessment could be conducted.The ORR was 100.0%, with 19 patients achieved CR (19/31),14 patients achieved PR (12/31). 2 patients developed tumor recurrence after achieved CR within one year.The most common 3-4 level AEs with RI-CHOP were neutrophil count decreased(14/31), thrombocytopenia(5/31) and typically occurred within the 4~6 cycles. Other 1-2 level toxicity events were subcutaneous hemorrhage(4/31),nausea(18/31),fatigue(10/31)and reactivation of varicella zoster virus(3/31). Two patients discontinued oral Zanubrutinib due to oral ulceration and hematuria. Image:Summary/Conclusion: RI-CHOP could be one of the promising choice for DE-DLBCL patients with fair physical condition,and could achieve high ORR and CRR. This study demonstrated a manageable safety profile of the combination regimen.

P1234: REAL-WORLD EXPERIENCE OF OUTCOMES WITH GLOFITAMAB SALVAGE THERAPY FOR RELAPSE/REFRACTORY B-CELL LYMPHOMA IN TAIWAN: MINIMAL SAFETY CONCERN WITH HEPATITIS B REACTIVATION

Background: Glofitamab, a T-cell-engaging bispecific antibody (Ab) with a novel 2:1 configuration conferring robust bivalency for CD20 and monovalency for CD3, has recently shown promising activity in its phase I/II trial as a salvage therapy in various major subtypes of B-cell lymphoma. Few studies, however, have described the use of glofitamab in a real-world clinical setting. Aims: We aimed to depict the efficacy and safety profiles of glofitamab as a salvage therapy for patients with diffuse large B-cell lymphoma (DLBCL) and other subtype of B-cell lymphoma in the real-world setting with a special focus on the risk of hepatitis B virus (HBV) reactivation. Methods: The clinical data of patients with DLBCL or other B-cell lymphomas who had received ≥3 lines of prior therapies and received glofitamab salvage therapy in a compassionate use program in Nov. 2020 - Dec. 2021 were retrospectively analyzed. The treatment protocol included obinutuzumab pretreatment 1000mg given 7 days before the first glofitamab dose, followed by step-up dose of glofitamab administration: 2.5mg on Day 1 and 10mg on Day 8 of cycle 1, and then 30mg on Day 1 of cycle 2-12 (21-day cycles). Results: As of the end of 2021, 26 patients from two medical centers in Taiwan, 11(43%) of whom were females, were enrolled. Among them, 18 were diagnosed with de novo DLBCL, 3 with transformed large B-cell lymphoma, and 5 with other subtypes of B-cell lymphoma. The median age was 57 years (26-75). Among the 18 cases with de novo DLBCL, 10(56%) had non-germinal center subtype, and 9(50%), double-hit/triple-hit lymphoma. Extra-nodal lesions were observed in 12(46%) patients, and 7(27%), marrow involvement. Elevated LDH levels occurred in 15 (58%) patients. Median prior therapies were 5 (3–10) with 24(92%) patients having received ≥4 prior therapies. All patients had received prior rituximab therapy, 6(23%), autologous or allogeneic stem cell transplantation (SCT), and 9(35%), polatuzumab salvage. Nineteen (79%) patients were refractory to their most recent regimen. Median cycles of glofitamab treatment were 5 (1-12). With the median follow-up of 9 months, the median overall survival was 6 months. The overall response and complete response rates were 50% and 23%, respectively. The remissions are durable (Figure 1): among 13 responders, 8 are continuing the treatment, 1 finished the planned 12 cycles of therapy, 1 had consolidated autologous SCT in remission status, and 2 passed away because of infections in remission status; only one case had disease relapse after achieving remission. No case has had disease progression after achieving an initial response. Cytokine releasing syndrome (CRS) occurred in 15(58%) patients; most of them occurred in the initial two cycles and were mostly of grade 1/2 severity except two cases (8%) with grade 3 CRS, both resulted from transaminitis. No grade 4/5 CRS, neurological toxicity, or fatal toxicity was observed. In terms of HBV infection, 7 patients were HBs antigen(+) and 6 of them had concurrent prophylactic HBV therapy during glofitamab treatment, whereas 11 patients were anti-HBc antibody(+)/HBs antigen(-) and 2 of them received prophylactic HBV therapy. No HBV reactivation event was observed in this cohort of patients. Image:Summary/Conclusion: In the real-world setting, glofitamab remains an effective salvage treatment for patients with heavily pretreated relapse/refractory DLBCL and B-cell lymphomas. No new safety issues were observed. With optimal prophylaxis, the risk of HBV reactivation would not be of concern during glofitamab treatment.

P1731: IBRUTINIB PLUS RCHOP VERSUS RCHOP ONLY, IN YOUNG PATIENTS WITH ACTIVATED B CELL-LIKE DIFFUSE LARGE B-CELL LYMPHOMA (ABC-DLBCL): A COST EFFECTIVENESS ANALYSIS

Background: The standard chemoimmunotherapy for Diffuse Large B Cell Lymphoma (DLBCL) is RCHOP (Rituximab, Cyclophosphamide, doxorubicin Hydrochloride, vincristine/Oncovin, and Prednisone), improving progression free and overall survival. However, many patients require subsequent treatment after refractory/relapsed disease. Molecular B-cell differentiation subtypes of DLBCL have prognostic implications, with the ABC subtype being associated with inferior prognosis. As the pathophysiology of ABC-DLBCL involves a chronically active B-cell antigen receptor pathway, it was hypothesised that higher-risk ABC-subtype population may benefit from a Bruton’s tyrosine kinase inhibitor, such as ibrutinib. Thus, the PHOENIX trial exploring the outcomes of adding ibrutinib to RCHOP (I-RCHOP) for patients with ABC-DLBCL was developed. Overall, it was found that I-RCHOP yielded favourable outcomes for patients younger than 60-years, as compared to older patients, whose event free survival did not improve and had worse outcomes due to toxicity. Aims: As addition of ibrutinib may improve survival for younger patients, our study aimed to inform clinical decision-making using a cost-effectiveness decision analysis model, and to compare R-CHOP, with and without ibrutinib for patients with ABC-DLBCL. Methods: A comprehensive Markov decision analysis model was designed (TreeAge Pro Healthcare) to compare I-RCHOP to RCHOP alone in a hypothetical cohort of patients younger than 60-years and newly diagnosed with ABC-DLBCL. The patients underwent either treatment pathway and survived, experienced adverse events (e.g., febrile neutropenia), relapse, or died. Available data on salvage treatment, autologous stem cell transplantation and novel therapies such as chimeric antigen receptor T-cell (CAR-T) for relapsed/refractory disease, were incorporated. The probabilities of transitioning between states were evaluated on a 3-month cycle for a lifetime horizon of 30 years. Costs were obtained from a Canadian public health payer’s perspective (CAN$1=US$0.78) and inflation-adjusted for 2022. Data on health state utilities were incorporated, and sensitivity analyses were performed for key variables. An annual discount rate of 1.5% to both quality-adjusted life-expectancies (QALEs) was utilised. Model variability and uncertainty were assessed through probabilistic sensitivity analyses over 10,000 simulations. Results: Probabilistic analyses showed that, for a willingness-to-pay (WTP) threshold of CAN$150,000/QALE, the addition of ibrutinib to RCHOP chemotherapy in younger patients with ABC-DLBCL was more cost-effective. I-RCHOP had greater QALE (7.9 years [SD: 0.04]) and the incremental cost-effectiveness ratio (ICER; cost gained per QALE) was CAN$16,478.84/QALE compared with RCHOP only strategy (QALE: 5.3 years [SD: 0.02]). Sensitivity analyses included key variables, including probability of adverse events, mortality associated with relapse and next-line managements, and showed that the model was robust. Image:Summary/Conclusion: Our results informed us that I-RCHOP is more costly given the currently high market price for ibrutinib in Canada, however suggested that the preferred cost-effective treatment strategy for younger patients with ABC-DLBCL is RCHOP with ibrutinib. This approach was analysed to be dominant, when considering the high costs of salvage therapies such as stem cell transplantation and CART therapy, along with adverse events, overall survival, and higher quality of life. This decision-analytic model, though not absolute, provided relevant and robust results to help inform clinical decision making.

PB2141: CLINICOPATHOLOGICAL FEATURES AND OUTCOME OF CD5 POSITIVE DIFFUSE LARGE B CELL LYMPHOMA AND THE SIGNIFICANCE OF CD5 EXPRESSION STRENGTH: 10-YEAR SINGLE CENTER EXPERIENCE

Background: CD5 positive (CD5+) diffuse large B cell lymphoma (DLBCL) is a rare subtype of DLBCL encompassing 5-10% of patients (pts) with DLBCL, and it is characterized by poor outcome. Aims: To identify clinicopathological features of CD5+ DLBCL in a cohort of pts managed at Clinic for Hematology, Clinical Center of Serbia during a 10-year period (2012-2021). Methods: We retrospectively analyzed immunohistochemistry (IHC) results of biopted tumor tissue of 537 pts with DLBCL NOS. Survival analysis was performed using Kaplan-Meier method and log-rank test. Results: Out of a total of 537 pts, in 211 (39.3%) CD5 was not analyzed by IHC, while in the remaining 326 (60.7%) was. Among them, 27 (8.3%) were found to be positive for CD5, out of which 10 pts were designated at the pathology report as CD5 +/- (5 pts) or CD5 -/+ (5 pts), while the rest 17 pts were clearly CD5+. In CD5 positive cohort, 52% of pts were men and median age at diagnosis was 63 years. ECOG performance status (PS) was poor (≥2) in 8 (29.6%) pts. One third of pts had advanced stage disease (Ann Arbor III/IV), while the rest two thirds were limited stage (I and II). Eleven out of 26 pts (42.3%) presented with B symptoms, 3/26 (11.5%) expressed bulky disease, while two thirds presented with extranodal disease. More pts (13/23 or 56.5%) were of nonGCB subtype according to IHC, while 4 out of 11 pts (36.4%) analyzed for c-myc protein expression were double expressors. Median Ki-67 proliferative index was 80%. Almost half of pts (47.6%) had increased initial lactate dehydrogenase (LDH) activity, while median beta-2 microglobulin (b2m) level was 3.38 mg/L. Nine out of 26 pts (34.6%) were IPI>2, while the rest 17 pts were IPI 0-1. Vast majority (25/27, 92.6%) were treated with chemoimmunotherapy in the first line, most of them with anthracycline-based protocols, 1 patient received cyclophosphamide, vincristine, prednisone (COP), and 1 patient succumbed before treatment commencement. Among treated pts with known outcome after first line, 18 (72%) pts achieved complete remission, 4 (16%) achieved partial response, while 3 (12%) pts did not respond to treatment. Median progression-free survival (PFS) after first treatment line for all pts in CD5 positive cohort was 25 months (95%CI 13.76-36.24), while median overall survival (OS) was not reached. Age at diagnosis, presence of B symptoms, and extranodal disease did not significantly influenced PFS and OS. Patients with bulky disease, nonGCB subtype, and double expressors experienced significantly shorter PFS (p=0.03, P=0.043, and p=0.025, respectively), but these features did not impact OS. On the other hand, b2m levels >3.38 mg/L, LDH >1x upper limit normal, and IPI >2 were significantly associated with shorter OS (p=0.014, p=0.01, and p=0.015, respectively), while they were not significant regarding PFS. ECOG PS >1 was significantly associated with both poor PFS and OS (p=0.005 and p=0.002, respectively). Intrestingly, pts designated as CD5+ at pathology reports experienced median PFS of 20 months in contrast to 52 months in pts descripted as CD5+/- and CD5-/+ (p=0.021). However, the difference between these two subgroups regarding OS was not observed. Summary/Conclusion: In our CD5+ DLBCL cohort, bulky disease, nonGCB, and double expressors were associated with shorter PFS, higher b2m, LDH, and IPI correlated with shorter OS, while higher ECOG PS was associated with shorter both PFS and OS. Median PFS after 1st treatment line was around 2 years, while median OS was not reached. Strenght of CD5 expression was significantly associated with PFS. CD5 should be mandatory within IHC for DLBCL.

Systems Drug Discovery for Diffuse Large B Cell Lymphoma Based on Pathogenic Molecular Mechanism via Big Data Mining and Deep Learning Method.

Diffuse large B cell lymphoma (DLBCL) is an aggressive heterogeneous disease. The most common subtypes of DLBCL include germinal center b-cell (GCB) type and activated b-cell (ABC) type. To learn more about the pathogenesis of two DLBCL subtypes (i.e., DLBCL ABC and DLBCL GCB), we firstly construct a candidate genome-wide genetic and epigenetic network (GWGEN) by big database mining. With the help of two DLBCL subtypes’ genome-wide microarray data, we identify their real GWGENs via system identification and model order selection approaches. Afterword, the core GWGENs of two DLBCL subtypes could be extracted from real GWGENs by principal network projection (PNP) method. By comparing core signaling pathways and investigating pathogenic mechanisms, we are able to identify pathogenic biomarkers as drug targets for DLBCL ABC and DLBCL GCD, respectively. Furthermore, we do drug discovery considering drug-target interaction ability, drug regulation ability, and drug toxicity. Among them, a deep neural network (DNN)-based drug-target interaction (DTI) model is trained in advance to predict potential drug candidates holding higher probability to interact with identified biomarkers. Consequently, two drug combinations are proposed to alleviate DLBCL ABC and DLBCL GCB, respectively.

Abstract 741: Evaluation of etiologic heterogeneity for risk of diffuse large B-cell lymphoma (DLBCL) subtype defined by cell-of-origin

Abstract Background: DLBCL is the most common non-Hodgkin lymphoma subtype in western countries and is clinically heterogeneous. Gene expression profiling has identified two major biologically distinctive DLBCL subtypes defined by their cell-of-origin (COO): germinal center B-cell (GCB) - characterized by BCL2 rearrangement and C-REL amplification, and activated B-cell (ABC) - characterized by constitutive activation of the NF-kB pathway. We evaluated putative DLBCL risk factors for etiologic heterogeneity as defined by COO. Methods: We used a clinic-based study of newly diagnosed NHL cases and frequency matched controls, enrolled from 2002-2014, with a total of 687 DLBCL cases and 2253 controls for this analysis. Using formalin-fixed, paraffin-embedded tumor tissue, we determined COO by either digital expression profiling (NanoString; classified as GCB, ABC, undetermined) or clinically using the Hans algorithm (immunohistochemical markers; classified as GCB, non-GCB, undetermined). Integrating these two sources of COO data, there were 271 GCB, 170 non-GCB, and 246 undetermined/missing (mainly due to lack of tissue) cases. Risk factor data were collected from self-administered questionnaires and included family history of hematologic malignancy; history of atopy, allergy, asthma, eczema, or autoimmune disease; blood transfusion; vaccination history; regular low-dose aspirin use; body mass index (BMI) 2 years prior diagnosis/enrollment; smoking history; alcohol consumption (never/current/former); leisure-time physical activity; and recreational sun exposure. Polytomous logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals for COO subtypes, adjusted for age, sex and residence. Results: The median age of cases was 64 years with 55% male; the median age of controls was 64 years and 53% male. The association with BMI (30+ vs. 18.5-24.9 kg/m2) was stronger for non-GCB (OR=2.21; 1.40-3.49) than for GCB (OR=1.70; 1.21-2.40) DLBCL (P-heterogeneity 0.02), while a family history of hematologic malignancy was associated with non-GCB (OR=2.27; 1.47-3.50) but not GCB (OR=1.30; 0.86-1.96) DLBCL, although the P-heterogeneity was not significant (P=0.13). For GCB, there was an inverse association with former (vs. never) alcohol use for GCB (OR=0.57; 0.39-0.83) but not for non-GCB (OR=0.98; 0.61-1.57) DLBCL (P-heterogeneity 0.007), and an inverse association with regular use of low-dose aspirin for GCB (OR=0.64; 0.47-0.87) but not for non-GCB (OR=0.88; 0.61-1.25) DLBCL (P-heterogeneity 0.05). No other risk factors evaluated showed important heterogeneity by COO. Conclusions: These initial results suggest most DLBCL risk factors do not show etiologic heterogeneity by DLBCL COO, although associations with BMI and family history with non-GCB DLBCL and alcohol and low-dose aspirin use with GCB DLBCL warrant follow-up. Citation Format: Geffen Kleinstern, Dennis P. Robinson, Lisa M. Rimsza, Melissa C. Larson, Rebecca L. King, Grzegorz S. Nowakowski, Carrie A. Thompson, Stephen M. Ansell, Matthew J. Maurer, Andrew L. Feldman, Susan L. Slager, Anne J. Novak, Thomas M. Habermann, James R. Cerhan. Evaluation of etiologic heterogeneity for risk of diffuse large B-cell lymphoma (DLBCL) subtype defined by cell-of-origin [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 741.

Immunophenotypic Landscape and Prognosis-Related mRNA Signature in Diffuse Large B Cell Lymphoma.

Diffuse large B cell lymphoma (DLBCL) exhibits a tightly complexity immune landscape. In this study, we intended to identify different immune phenotype and to examine the immune related mRNA signature for clinical characteristic, therapeutic responsiveness as well as risk stratification and survival prediction in DLBCL. We identified two immune infiltration subtypes of DLBCL patients based on 28 immune cell types. GSEA analysis uncovered the concordant classification of two robust significant subtypes of DLBCL. Considering the convenient application of the immune infiltration subtypes for prognostic prediction, we developed a risk score based on the differentially expressed genes between the Immunity-H and Immunity-L groups. By a least absolute shrinkage and selection operator (LASSO)-Cox regression model, a sixteen-gene risk signature, comprising ANTXR1, CD3D, TIMP1, FPR3, NID2, CTLA4, LPAR6, GPR183, LYZ, PTGDS, ITK, FBN1, FRMD6, PLAU, MICAL2, C1S, was established. The comprehensive results showed that the high-risk group was correlated with lower immune infiltration, more aggressive phenotypes, lower overall survival and more sensitive to lenalidomide. In contrast, a low-risk group score was associated with higher immune infiltration, less aggressive phenotypes, better overall survival and more likely to benefit from PD-1/PD-L1 inhibitors. Finally, a nomogram comprised of the risk score and IPI score was verified to more accurately predict the overall survival of DLBCL than traditional clinical prediction models. Altogether, our data demonstrate the heterogeneity of immune patterns within DLBCL and deepen our molecular understanding of this tumor entity.

Molecular Diagnostic Review of Diffuse Large B-Cell Lymphoma and Its Tumor Microenvironment.

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma. It is a clinically and morphologically heterogeneous entity that has continued to resist complete subtyping. Molecular subtyping efforts emerged in earnest with the advent of gene expression profiling (GEP). This molecular subtyping approach has continued to evolve simultaneously with others including immunohistochemistry and more modern genomic approaches. Recently, the veritable explosion of genomic data availability and evolving computational methodologies have provided additional avenues, by which further understanding and subclassification of DBLCLs is possible. The goal of this review is to provide a historical overview of the major classification timepoints in the molecular subtyping of DLBCL, from gene expression profiling to present day understanding.

Treatment at high-volume facilities is associated with improved overall survival for patients with cutaneous B-cell lymphoma

To the Editor: Primary cutaneous B-cell lymphoma (CBCL), which comprises approximately 25% of cutaneous lymphomas, is much less common than cutaneous T-cell lymphoma. CBCLs require careful clinicopathologic correlation for accurate diagnosis and can range from more indolent (marginal zone lymphoma and follicle center lymphoma) to more aggressive (eg, diffuse large B-cell lymphoma) subtypes. Given the rarity and heterogeneity of CBCL, there is limited high-level data to guide management, with cases typically treated using a multidisciplinary approach using expert opinion and data from observational studies.

Biological and Clinical Implications of Gene-Expression Profiling in Diffuse Large B-Cell Lymphoma: A Proposal for a Targeted BLYM-777 Consortium Panel as Part of a Multilayered Analytical Approach.

Simple SummaryThis review summarizes gene-expression profiling insights into the background and origination of diffuse large B-cell lymphomas (DLBCL). To further unravel the molecular biology of these lymphomas, a consortium panel called BLYM-777 was designed including genes important for subtype classifications, genetic pathways, tumor-microenvironment, immune response and resistance to targeted therapies. This review proposes to combine this transcriptomic method with genomics, proteomics, and patient characteristics to facilitate diagnostic classification, prognostication, and the development of new targeted therapeutic strategies in DLBCL.Gene-expression profiling (GEP) is used to study the molecular biology of lymphomas. Here, advancing insights from GEP studies in diffuse large B-cell lymphoma (DLBCL) lymphomagenesis are discussed. GEP studies elucidated subtypes based on cell-of-origin principles and profoundly changed the biological understanding of DLBCL with clinical relevance. Studies integrating GEP and next-generation DNA sequencing defined different molecular subtypes of DLBCL entities originating at specific anatomical localizations. With the emergence of high-throughput technologies, the tumor microenvironment (TME) has been recognized as a critical component in DLBCL pathogenesis. TME studies have characterized so-called “lymphoma microenvironments” and “ecotypes”. Despite gained insights, unexplained chemo-refractoriness in DLBCL remains. To further elucidate the complex biology of DLBCL, we propose a novel targeted GEP consortium panel, called BLYM-777. This knowledge-based biology-driven panel includes probes for 777 genes, covering many aspects regarding B-cell lymphomagenesis (f.e., MYC signature, TME, immune surveillance and resistance to CAR T-cell therapy). Regarding lymphomagenesis, upcoming DLBCL studies need to incorporate genomic and transcriptomic approaches with proteomic methods and correlate these multi-omics data with patient characteristics of well-defined and homogeneous cohorts. This multilayered methodology potentially enhances diagnostic classification of DLBCL subtypes, prognostication, and the development of novel targeted therapeutic strategies.

Genetic Subtyping and Phenotypic Characterization of the Immune Microenvironment and MYC/BCL2 Double Expression Reveal Heterogeneity in Diffuse Large B-cell Lymphoma

Diffuse large B-cell lymphoma (DLBCL) is molecularly and clinically heterogeneous, and can be subtyped according to genetic alterations, cell-of-origin, or microenvironmental signatures using high-throughput genomic data at the DNA or RNA level. Although high-throughput proteomic profiling has not been available for DLBCL subtyping, MYC/BCL2 protein double expression (DE) is an established prognostic biomarker in DLBCL. The purpose of this study is to reveal the relative prognostic roles of DLBCL genetic, phenotypic, and microenvironmental biomarkers. We performed targeted next-generation sequencing; IHC for MYC, BCL2, and FN1; and fluorescent multiplex IHC for microenvironmental markers in a large cohort of DLBCL. We performed correlative and prognostic analyses within and across DLBCL genetic subtypes and MYC/BCL2 double expressors. We found that MYC/BCL2 double-high-expression (DhE) had significant adverse prognostic impact within the EZB genetic subtype and LymphGen-unclassified DLBCL cases but not within MCD and ST2 genetic subtypes. Conversely, KMT2D mutations significantly stratified DhE but not non-DhE DLBCL. T-cell infiltration showed favorable prognostic effects within BN2, MCD, and DhE but unfavorable effects within ST2 and LymphGen-unclassified cases. FN1 and PD-1-high expression had significant adverse prognostic effects within multiple DLBCL genetic/phenotypic subgroups. The prognostic effects of DhE and immune biomarkers within DLBCL genetic subtypes were independent although DhE and high Ki-67 were significantly associated with lower T-cell infiltration in LymphGen-unclassified cases. Together, these results demonstrated independent and additive prognostic effects of phenotypic MYC/BCL2 and microenvironment biomarkers and genetic subtyping in DLBCL prognostication, important for improving DLBCL classification and identifying prognostic determinants and therapeutic targets.