Double Expression Research Articles

Targeting MYC-driven lymphoma: lessons learned and future directions.

MYC plays a central role in tumorigenesis by orchestrating cell proliferation, growth and survival, among other transformation mechanisms. In particular, MYC has often been associated with lymphomagenesis. In fact, MYC overexpressing lymphomas such as high-grade B-cell lymphoma (HGBL) and double expressor diffuse large B-cell lymphomas (DLBCL), are considered addicted to MYC. In such a context, MYC targeting therapies are of special interest, as MYC withdrawal is expected to result in tumor regression. However, whether high MYC levels are always predictive of increased sensitivity to these approaches is not clear yet. Even though no MYC inhibitor has received regulatory approval to date, substantial efforts have been made to investigate avenues to render MYC a druggable target. Here, we summarize the different classes of molecules currently under development, which mostly target MYC indirectly in aggressive B-cell lymphomas, paying special attention to subtypes with MYC/BCL2 or BCL6 translocations or overexpression.

Identification of MYC/BCL2 Double-expressers Lymphomas in Diffuse Large B Cell Lymphoma Patients and Association with their Prognostic Parameters and Survival Rates: A Single Centre Experience

Introduction: Diffuse large B cell lymphoma (DLBCL) is a heterogenous disease some of which show co-expression of c-MYC and BCL2 and they are known as double expressers (DE) lymphoma. DE lymphoma has been shown to be associated with aggressive clinical course and poor outcome in comparison to those without co-expression. The association of DE lymphomas with their prognostic parameters and the overall survival rate of DE compared to non-DE lymphoma patients were investigated. Method: 66 formalin-fixed paraffin-embedded DLBCL cases were subjected to c-MYC and BCL2 immunohistochemical staining. Results: Out of 66 cases, 25(37.9%) cases showed c-MYC and BCL2 co-expression. Majority of the patients were in age category of ≥ 60 years (68.0%). Male and female distribution were almost equal. DE lymphoma was significantly associated with ABC subtype in comparison to GCB subtype (p= 0.026). Median survival time for DE was 29 months and non-DE was 34 months. Log rank analysis showed there was no significant difference in the overall survival rate of DE and non-DE patients (p=0.401). Conclusion: This study showed significant association between DE lymphomas and ABC subtype. Identification of DE lymphoma with ABC subtype may guide the clinicians in identifying patients with poorer outcome hence a more aggressive treatment may be offered to this group.

Impact of Double Expression of MYC and BCL-2 on Outcomes in Primary CNS Lymphoma: A UK Multicentre Analysis

Introduction Primary central nervous system lymphoma (PCNSL) is a rare B cell lymphoma with an aggressive course. Relapses remain common even with intensive immuno-chemotherapy treatment options such as MATRix and consolidation with autologous stem cell transplant (ASCT), and prognostic tools are limited. Although, double expressor status (co-expression of both MYC and BCL-2) is well established in systemic de novo DLBCL, its prognostic impact in PCNSL has been understudied. Here we evaluated the prognostic value of BCL-2, BCL-6, and MYC expression in a retrospective cohort of treated PCNSL patients diagnosed at 7 academic centres in the UK. Methods We performed this retrospective analysis on histologically-confirmed PCNSL patients diagnosed consecutively between 1st May 2015 and 31st May 2020. Treatment with a high-dose methotrexate-based chemotherapy regimen was a mandatory inclusion criterion. BCL-2 and MYC immunohistochemistry (IHC) protein expression data were collated from local diagnostic histology reports and double expressor (DE) status was defined as per WHO criteria (MYC: surface expression > 40% of cells and BCL-2: >50% of cells). Outcomes included response rates, progression-free survival (PFS) and overall survival (OS). Where available, diagnostic fluorescence in situ hybridisation (FISH) data was collected for BCL-2, BCL-6 and MYC loci translocations. Cox-regression for PFS and OS were used to determine baseline predictors of response and survival and to construct multivariable models for factors associated with outcome. Results In total, 242 patients were analysed. Key baseline patient characteristics and IHC data are summarised in Table 1. Median age was 65 years (IQR 56-71), 60% were male and 64% of patients had an ECOG performance status (PS) of 0-1. One hundred and seventy-four (72%) patients received treatment with MATRix chemotherapy; these patients were younger (median age 62 vs. 73 years, p< 0.01), had better baseline PS (PS ≤ 1: 75% vs. 37%, p< 0.01) and higher rates of consolidation with BCNU-thiotepa ASCT (58% vs. 7%, p< 0.01). Double expressor (DE) status was assessable in 169/242 (69%) patients. Reasons for absent DE status were missing IHC expression data (BCL-2: n=28; MYC: n=44) or IHC expression data not reported in line with WHO recommended criteria (BCL-2: n=45; MYC: n=7). In the DE-assessable cohort (n = 169 patients), 40% of patients had DE PCNSL, higher than estimates of DE prevalence in systemic DLBCL (reported rates between 20 and 30%). As only 40 cases (17%) underwent FISH assessment for concurrent MYC and BCL-2 loci translocation (double hit status), correlation between double hit and DE status was not possible. DE status was not associated with patient age at diagnosis, baseline PS or treatment received. With a median follow up of 1.7 years, 34% of patients relapsed and 45% died. Although single MYC or BCL-2 expression alone had no significant association with OS or PFS in the entire cohort, DE status was associated with significantly poorer PFS, and earlier relapse (median 0.86 years vs. 2.77 years; HR 1.61 (1.07 - 2.41); p=0.021) (Fig. 1). In a subgroup analysis restricted to patients treated with MATRix chemotherapy (n = 116 patients), there was a trend towards inferior PFS and OS, although this did not reach significance in a univariable analysis. However, the adverse prognostic impact of DE status on PFS was maintained in a multivariable analysis modelling age, baseline PS, treatment received, ASCT consolidation status and DE status both for the entire cohort (HR 1.75 (1.15 - 2.66); p<0.01) and the MATRix treated subgroup (HR 1.91 (1.08 - 3.36); p=0.03). A trend towards an association between DE status and OS was noted but did not reach significance in either a univariable or multivariable analysis. We observed no significant difference in PFS or OS between DE-PCNSL and non-DE-PCNSL patients who received MATRix and consolidation with ASCT, perhaps indicating that the adverse impact of DE status is modified by this treatment strategy, although the sample size was small (n=66). Conclusions In a large, retrospective cohort of PCNSL patients treated at 7 UK academic treatment centres, double expression of MYC and BCL-2 by IHC was associated with inferior PFS even in patients treated with MATRix chemotherapy. Validation of this finding in independent cohorts is warranted. ___ JO, CPF and KC share senior authorship Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A Preliminary Analysis of Chidamide Combined with R-GemOx (rituximab, gemcitabine and oxaliplatin) As Salvage Treatment for Transplant-Ineligible Patients with Relapsed/Refractory Diffuse Large B-Cell Lymphoma: A Prospective, Multicenter, Single-Arm, Phase II Study

Background: The clinical outcomes remain significantly poor for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL), especially transplantation-ineligible R/R DLBCL. R-GemOx (rituximab, gemcitabine and oxaliplatin) is considered as one of the effective and acceptable side-effect therapeutic regimens for those patients. Chidamide, a histone deacetylase (HDAC) inhibitor, plays an anti-tumor effect by selectively inhibiting activity of HDAC1, 2, 3 and 10. Our preclinical finding indicated that chidamide combined with R-GemOx may have potential synergistic anti-tumor effect in DLBCL (unpublished data). Therefore, a prospective, multicenter, single-arm, phase II study (ClinicalTrials.gov: NCT04022005) was initiated to evaluate the efficacy and toxicity of chidamide in combination with R-GemOx (CR-GemOx) regimen for transplant-ineligible R/R DLBCL. Here, we reported the preliminary results of this ongoing study. Methods: Patients aged 18-75 years with transplantation-ineligible R/R DLBCL who failed anthracycline-based chemotherapy were enrolled. The CR-GemOx regimen was administered as follows: chidamide, 20 mg, P.O., twice per week; rituximab 375mg/m2, d1, intravenous drip; gemcitabine 1000mg/m2, d2, intravenous drip; oxaliplatin 100mg/m2, d2, intravenous drip. Repeat cycle every 21 days (up to 6 cycles). Patients achieved complete response (CR) or partial response (PR) were administered chidamide as maintenance therapy. The primary endpoint was overall response rate (ORR). Secondary endpoints included duration of response, progression-free survival (PFS), overall survival (OS) and toxicities. The response was evaluated by using Lugano 2014 criteria. The safety was assessed according to Common Terminology Criteria for Adverse Events version 5.0. Results: A total of 41 patients were enrolled between August 2019 and June 2022, including 26 patients (63.4%) with relapsed diseases and 15 patients (36.6%) with refractory diseases. The median age was 60 years (range: 26-74 years). Twenty patients were male (48.8%), and the median number of prior lines of therapy was 1 (range: 1-3). Baseline characteristics were listed in Table 1. All patients received response assessments, the ORR and CR rate were 61.0% and 31.7%, respectively. Notably, among 14 patients with bcl-2/c-myc double-expression (DE), 3 patients achieved CR (21.4%) and 5 patients had PR (35.7%). Sixteen patients received chidamide maintenance therapy. At the cut-off date of July 21st, 2022, the median PFS was 7.6 months (95% confidence interval: 2.7 - 12.5 months) with a median follow-up of 10.1 months. There were not significant differences in ORR (57.1% versus 64.0%, p=0.673) and median PFS (4.6 versus 12.4 months, p=0.079) between DE and non-DE patients. In the safety analysis population, the most common (≥20%) treatment-related adverse events (AEs) at any grade were neutropenia (65.9%, 27/41), thrombocytopenia (63.4%, 26/41), anemia (56.1%, 23/41), fatigue (43.9%, 18/41) (Table 2). Grade 3/4 AEs were neutropenia (41.5%, 17/41), thrombocytopenia (34.1%, 14/41), anemia (4.9%, 2/41), febrile neutropenia (2.4%, 1/41), diarrhea (2.4%, 1/41), and elevated triglyceride (2.4%, 1/41) (Table 2). Lung infection of grade ≥3 was observed in one patient only (2.4%, 1/41). Dose reductions of chidamide occurred in 13 patients due to AEs (thrombocytopenia, n=5; neutropenia, n=5; febrile neutropenia, n=1; diarrhea, n=2). Conclusion: The CR-GemOx regimen demonstrates encouraging efficacy in transplant-ineligible R/R DLBCL patients. The common AEs at any grade and grade 3/4 were neutropenia, and thrombocytopenia. Furthermore, lone-term efficacy and safety evaluation in larger cohort is ongoing. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Durable Responses from Acalabrutinib in Combination with Rituximab, Cyclophosphamide, Doxorubicin, Vincristine and Prednisolone (R-CHOP) As First Line Therapy for Patients with Diffuse Large B-Cell Lymphoma (DLBCL): The Accept Phase Ib/II Single Arm Study

Introduction: R-CHOP remains the standard of care for DLBCL but fails in a proportion of patients (pts.) either through refractory lymphoma or relapse after achieving an initial remission. In the phase III PHOENIX study (NCT01855750), the addition of the Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib (I) to R-CHOP (R-CHOP-I) did not improve the outcome for non-germinal centre like DLBCL. However, R-CHOP-I treated pts. who were aged less than 60 years had a significantly improved progression free survival (PFS) and overall survival (OS) compared to those receiving R-CHOP alone. In pts. aged over 60 years, the addition of I increased toxicity and compromised the delivery of R-CHOP. Acalabrutinib (A) is a second generation BTKi, with enhanced kinase selectivity and potential for better efficacy and tolerability over first-generation inhibitors. Therefore, we combined A with R-CHOP in untreated de novo DLBCL to understand its safety profile and efficacy. Methods: Eligible pts. were treatment naive with histologically confirmed DLBCL. All received 6 cycles of R-CHOP on a standard 21-day schedule, with the addition of A in cycles 2-6. A continuation phase of A only, for 2 cycles of 28 days was administered after R-CHOP-A. The primary objective of the phase Ib was to establish a recommended phase II dose (RP2D) of A in combination with R-CHOP (modified 6+6 design) with 24 months follow-up. Phase II assessed the overall response rate (ORR) of the combination and ascertained additional safety information. Secondary endpoints included metabolic complete response rates (mCR), PFS and OS and their relation to the cell of origin (COO), pharmacokinetics and pharmacodynamics. COO was determined by HTG EdgeSeq transcriptome analysis. Recruitment of pts. over the age of 65 was suspended as an urgent safety measure (USM) following the abstract release of data from PHOENIX (Nov 2018). ACCEPT reopened to all ages after a comprehensive safety review by the Independent Data Monitoring Committee (Sep 2019). The trial was endorsed by CRUK (CRUKDE/16/006) and coordinated by Southampton Clinical Trials Unit. Results: From May 2017 to Jan 2020, 38 pts. were enrolled (safety population: pts. in receipt of any component of therapy). The median age was 64 years (range 24-80, 39% >65 years old); 76% stage III/IV; 71% abnormal LDH; 29% B symptoms; 34% bulk; 24% high IPI; 32% high-intermediate IPI. Seven of the enrolled pts. were found to be ineligible (insufficient material for translational work, 2pts.; taking a proton pump inhibitor during therapy, 2 pts.; follicular histology, 1pt.; abnormal LFTs at baseline, 1pt.; age >65 at time of USM, 1 pt). There were no dose-limiting toxicities and the maximum tolerated dose was not reached. The RP2D was chosen as 100mg bd acalabrutinib. The most common ≥grade3 adverse events were neutropenia (34% of pts.), febrile neutropenia (16%) and diarrhoea (11%). The most frequently reported serious adverse event was febrile neutropenia (13% of pts.). Age did not compromise the delivery of full dose R-CHOP in combination with A. One of 7 eligible pts. in the first cohort (A 100mg od) progressed on therapy and subsequently died, 1 pt. not achieving mCR received additional radiotherapy. Twenty-four eligible patients received the RP2D in either dose escalation or expansion. Four pts. withdrew early from treatment (1 pt subject withdrawal, 2 pts. investigator withdrawal and 1pt. due to toxicity) and are included in the efficacy analysis. The RP2D ORR was 96% (95% CI 79-100) with 79% (95% CI 58-93) of pts. achieving a mCR (4 pts. partial response (PR), 1pts. stable disease (SD)). One pt. with MYC/BCL2/BCL6 rearrangements and 1 pt. with MYC/BCL6 rearrangement achieved a mCR; neither have progressed. mCR was achieved in 9 of 12 ABC pts. (83%), 9/9 GCB pts and 1/2 unclassified pts. (PR 2, 0, 1 pts. respectively, 1/1 fail). At the RP2D with a median follow-up of 30 months, the 24 months EFS was 90% (95% CI 66-97), PFS was 95% (95% CI 68-99) and OS was 96% (95% CI 73-99) - 1 pt. progressed at 11 months and 1 double expressor patient with SD received subsequent chemotherapy prior to progression then died of PD. R-CHOP did not affect the pharmacokinetics of A. Additional translational data will be presented. Conclusions: Acalabrutinib is well tolerated in combination with R-CHOP chemotherapy and may be associated with improved efficacy. This is being explored in the randomised REMoDL-A (NCT04546620) and ESCALADE (NCT04529772) trials.

Efficiency and Safety of Zanubrutinib Combined with R-CHOP Regimen in the Treatment of Newly Diagnosed Patients with Double Expressor Diffuse Large B-Cell Lymphoma: A Single-Center Retrospective Study

Efficiency and Safety of Zanubrutinib Combined with R-CHOP Regimen in the Treatment of Newly Diagnosed Patients with Double Expressor Diffuse Large B-Cell Lymphoma: A Single-Center Retrospective Study

Epidemiological Impact of Polatuzumab Vedotin Plus Rituximab, Cyclophosphamide, Doxorubicin and Prednisone (Pola-R-CHP) Use in Previously Untreated Diffuse Large B-Cell Lymphoma (DLBCL) in Terms of Second Line (2L) Treatment: An Ad Hoc Analysis from the POLARIX Study

Background: In the POLARIX study (NCT03274492), Pola-R-CHP demonstrated significantly improved progression-free survival (PFS) vs previous standard of care rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP; stratified hazard ratio [HR], 0.73; 95% confidence interval [CI]: 0.57-0.95; p=0.02), with a similar safety profile in patients (pts) with previously untreated DLBCL (Tilly H, et al. N Engl J Med 2022). Here we report an ad hoc analysis to evaluate the potential impact of Pola-R-CHP on 2L treatment, using results of the POLARIX study projected to the real-world DLBCL population. Methods: Data from pts across six countries were derived from POLARIX (data cut-off: June 28, 2021). 2L treatment was defined as the first treatment after progression, or treatment change due to toxicity or other reasons, whichever occurred first. 2L treatments were grouped into six categories: autologous stem cell transplant (ASCT), chemotherapy only (chemo), rituximab plus chemotherapy (R-chemo), radiotherapy (RT), clinical trials, and other therapy. Cumulative incidence of 2L treatment as a function of time was estimated using Fine-Grey methodology, with death as a competing risk; long-term extrapolation outcome was estimated using the mixture cure rate models fitted on PFS and overall survival data. A dynamic multi-cohort partition survival model was constructed to estimate population-level impact of first line (1L) DLBCL treatment with Pola-R-CHP on the incidence of 2L treatment, over a 10-year period (2023-2033). DLBCL population incidence (2018-2032) was based on age-specific rates taken from country-specific registries and applied to population counts for each age group using United Nations population data (United Nations. World Population Prospects 2019). The population distribution of International Prognostic Index (IPI) score 2-5 was assessed from literature and reflected 70% of diagnosed pts (Harrysson S, et al. Blood Cancer J 2021; Tuominen S, et al. Future Oncol 2022). DLBCL population incidence counts for IPI 2-5 were imputed into the dynamic model to parse the effects between treatment with Pola-R-CHP and R-CHOP. Results: Among pts who received 2L treatment in POLARIX (Pola-R-CHP, n=78; R-CHOP, n=109), the majority (84%) in both arms required subsequent treatment due to disease progression. In line with the previously reported PFS benefit, pts in the Pola-R-CHP arm received fewer 2L treatments than pts in the R-CHOP arm, with a 34% risk reduction (subdistribution HR, 0.66; 95% CI: 0.49-0.88); cumulative incidence of 2L treatment at 24 months was 17.1% (95% CI: 13.5-20.6) vs 24.4% (95% CI: 20.4-28.5), respectively (Figure A). At baseline, risk factors for requiring 2L treatment, after adjustment for treatment effect, were: Ann Arbor Stage III-IV, bulky disease, and double expressor lymphoma (DEL). Mortality as a competing risk to 2L was similar across both treatment arms. As expected, the types of 2L therapies used were similar between the Pola-R-CHP and R-CHOP arms of POLARIX (Pola-R-CHP vs R-CHOP, n [%]: ASCT, 16 [20.5] vs 25 [22.9]; R-chemo, 39 [50.0] vs 53 [48.6]; chemo, 5 [6.4] vs 7 [6.4]; RT, 10 [12.8] vs 12 [11.0]; clinical trials, 3 [3.8] vs 8 [7.3] [including chimeric antigen receptor T-cell therapy, n=2 vs n=1, respectively], and other therapy, 5 [6.4] vs 4 [3.7], respectively), suggesting that the use of Pola-R-CHP instead of R-CHOP in 1L DLBCL does not impact choice of 2L treatment strategy. In the real-world setting, replacing R-CHOP with Pola-R-CHP as 1L treatment in pts with IPI 2-5 would translate to a 27% cumulative reduction of 2L treatments during the 10-year period analyzed (Figure B). For the six countries studied, this would result in a total of 27,741 additional pts avoiding the burden of later-line therapies. Conclusions: Results demonstrate that 2L therapies used were similar between pts who received Pola-R-CHP vs R-CHOP, suggesting 1L use of Pola-R-CHP does not alter subsequent therapy selection. Moreover, analysis of the potential impact on 2L treatment in the next 10 years showed that Pola-R-CHP reduced the risk of undergoing 2L treatment compared with R-CHOP by 27%, including pts with high-risk tumor subsets such as DEL, translating to 27,741 pts across the countries studied. Further study with longer follow up is needed to determine the number of treatments that would have been avoided by these pts in the third-line setting and beyond. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Preliminary Result of Lenalidomide Combined with R-CHOP(R2-CHOP) in Newly Diagnosed Double-Expressor Diffuse Large B-Cell Lymphoma: A Prospective Phase II Clinical Trial

Background: Double expressor lymphoma (DEL) is a subtype of diffuse large B-cell lymphoma (DLBCL) defined as having increased expression of MYC (≥40%) and BCL-2 (≥50%) by immunohistochemistry (IHC). Patients with DEL have inferior outcomes when treated with standard immunochemotherapy. Previous studies illustrated that lenalidomide showed a significant clinical response in non-GCB DLBCL, and well tolerated when combined with R-CHOP. This study aims to investigate the efficacy and safety of lenalidomide combined with R-CHOP (R2-CHOP) in newly diagnosed DEL patients. Methods: Histologic diagnosis of DLBCL and MYC/BCL-2 expression by IHC were confirmed by central pathology prior to study therapy. Treatment regimen included lenalidomide 25 mg/d orally days 1-10 per 21days, plus standard R-CHOP21 for 6 cycles. The primary end point was 2-year progression free survival (PFS) per independent central radiology review. Secondary end points included 2-year event-free survival (EFS), overall response rate (ORR), overall survival (OS), and safety. Results: Between Oct 2019 and Aug 2021, 67 eligible patients were enrolled in this study. Median age was 58 (range 27-75) years. Forty-one (61.2%) patients were stage III-IV, and 35.8% of patients were IPI score ≥3. Non-GCB subtype was determined in 44 (65.7%) patients. Three patients detected double-hit lymphoma withdrew from the study per investigator's decision. Sixty patients were evaluable for response. Fifty-seven patients responded to therapy, with overall response rate of 95% (57/60), and complete response rate of 80% (48/60). With a median follow-up of 17.8 months, the estimated 1-year PFS rate was 85.3% (95%CI 75.9%-95.2%). And the 1-year EFS rate was 79% (95%CI 68.8%-90.3%). Median OS was not reached, and 1-year OS rate was 90.9% (95%CI 84.1%-98.1%). Grade 3 or 4 hematologic toxicities included neutropenia (67.2%), thrombocytopenia (19.4%), and anemia (4.5%). The most common nonhematologic adverse events were grade 1 to 2, including nausea, vomiting, fatigue, diarrhea, and mucositis. Grade 3 pneumonia occurred in 5 patients. Dose modification of lenalidomide or R-CHOP due to AEs were noted in 43.3% and 20.9% patients. No treatment-related death occurred in the study. Conclusion: Our preliminary data indicate promising activity of lenalidomide combined with R-CHOP for newly diagnosed DEL patients. R2CHOP regimen was feasible, with predictable and manageable adverse events. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Characterizing Diffuse Large B Cell Lymphoma (DLBCL) Disease Biology Features and Survival Outcomes By Patient Racial Groups Using Real World Data

Background Various real world data (RWD) studies have highlighted differences in the survival outcomes of DLBCL patients of different ethnicities and racial groups. However, few studies have examined the differences in DLBCL biology features in patients of different racial groups. Using RWD, we evaluated both biology features and survival outcomes of DLBCL patients from different racial groups. Method Our retrospective analysis used de-identified, real-world patient data from the Flatiron Health electronic health record-derived database. Inclusion criteria were patients with an initial diagnosis of DLBCL (ICD 9: 200x, 202x; ICD 10: C82x, C83x, C84x, C85x, C86x, C88x, C96x) between 1 January 2011 to 31 May 2022 and who had at least two documented clinical visits. Patients’ racial groups were classified into Asian, Black or African American, White, Others and Unknown; the Others group were patients not included in the other racial groups. The DLBCL disease features included cell-of-origin (COO) subtypes, double hit status (MYC and BCL2 translocations), double expressor status (MYC and BCL2 expression by immunohistochemistry) and International Prognostic Index (IPI) scores. Differences among racial groups were examined using the chi-square test with p-value<0.05 considered significant. Differences in overall survival (OS) by patients racial groups were analyzed using Kaplan Meier survival analysis and an adjusted Cox regression model for multivariable analysis. Results In total there were 8289 evaluable patients. The racial group distribution of the cohort was as follows: White (n = 5659, 68.3%), Others (n =1084, 13.1%) Black or African American ( n = 509, 6.1%), Asian (n = 185, 2.2%) and Unknown (n = 852, 10.3%); Fig. 1a. Disease biology features among patients of different racial groups were evaluated. There was a significant difference in the racial distribution between the two COO subtypes (p=0.045). Higher proportion of White patients had the germinal-center B-cell-like (GCB) subtype (n=1888/3127, 60.4%) compared to Asian (n=58/119, 48.7%) and Others (n=351/626, 56.1%) patients. Asian patients had the highest proportion of activated B-cell-like (ABC) subtype (n=61/119, 51.3%) compared to the other racial groups. No significant difference in racial group distribution was seen in double hit status. In terms of double expressor status, there was a significant difference in racial distribution (p = 0.008). More Asian patients had positive double expressor status (n=30/185, 16.2%) compared to the other racial groups. Racial distribution was significantly different between IPI categories (p = 0.028). Higher proportion of White patients presented with higher IPI scores compared to Asian, Black or African American patients. The univariate analysis showed that White patients had worse overall survival (median OS 85.3 months) than Black or African American patients (median OS 111.2 months), Asian patients (median OS 102.6 months) or Others patients (median OS 107.0 months); Fig. 1b. However, multivariable analysis, adjusted for age, gender, IPI and COO, showed no significant difference in OS between White patients and Black or African American (HR 0.89, 95% CI 0.75 - 1.06, p = 0.18) or Asian patients (HR 0.86, 95% CI 0.65 - 1.16, p = 0.31); though was a difference with the Others patients (HR 0.87, 95% CI 0.77-0.98, p =0.024) . Conclusions Using a RWD cohort, we described the disease characteristics and OS between DLBCL patients of different racial groups. Although differences were seen in COO and IPI scores, OS was not significantly different between racial groups in multivariable analysis except between White and Others patients . As the Others patients were a heterogenous group, in-depth study is warranted in the future to delineate true differences. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

CNCT19 CAR T-Cell Therapy in Relapsed or Refractory B-Cell Lymphoma: Long-Term Results of a Pilot Prospective Clinical Study

Background: Chimeric antigen receptor (CAR) T-cell targeting tumor cells depends on the single chain variable fragment (scFv) against the specific tumor antigen. Most anti-CD19 CAR-T products have the scFv deriving from hybridoma clone FMC63. We developed a new hybridoma clone HI19α which binds to distinct CD19 episodes. CNCT19 was a second-generation CAR T-cell with scFv derived from clone HI19α and 4-1BB/CD3-ζ costimulatory domain. The results of CNCT19 in pediatric and adult patients with relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia had previously been reported [Runxia Gu et al. J Hematol Oncol. 2020 Sep 7;13(1):122]. Herein, we reported the outcome and long-term follow-up of a pilot study administrating CNCT19 in relapsed or refractory B-cell lymphoma. This trial was registered at www.clinicaltrials.gov as NCT03029338. Methods: Patients with R/R CD19-positive B-cell lymphoma were eligible for this study. Subjects with active central nervous system involvement were excluded. Lymphodepleting chemotherapy comprising fludarabine (25~30mg/m2, day -4,-3,-2) and cyclophosphamide (350mg/m2 day -4, -2) was administrated once the CNCT19 product was available. We infused CNCT19 cells in three regimens: three-day split dose (10%-30%-60%, patient (P)1-P10), two-day split dose (40%-60%, P11-P17), and single dose (P18-20). Results: From May 2017 through March 2019, 20 patients were enrolled. Diagnosis of histological subtypes included diffuse large B-cell lymphoma not otherwise specified (DLBCL, NOS) in 14 (70%) patients, DLBCL transformed from chronic lymphocytic leukemia in 1 (5%) patient, follicular lymphoma (FL) grade 3b in 1 (5%) patient, and mantle cell lymphoma (MCL) in 4 (20%) patients. Considering the differences in efficacy and survival between the population with MCL and those with LBCL, we here reported the results of 16 patients who had diseases of DLBCL or FL 3b. The median age was 51 (range 16 to 69), and 62.5% were male. The majority (87.5%) of patients had advanced stage disease, and 11 (68.8%) had non-GCB immunophenotype. Double expressor lymphoma (DEL, cut-off for MYC, >=40%, BCL2, >=50%) was identified in 11 (68.8%) patients, with one of them having MYC and BCL2 rearrangement. TP53 mutation and/or deletion were detected in 5 of 6 (83.3%) patients. The patients had received a median of 3 (range 2 to 7) lines of prior therapy. Thirteen (81.3%) patients had diseases refractory to last-line therapy. The median dose of infused CNCT19 cells was 2.48×106 (range 1.87 to 5.06×106) per kilogram of body weight. Cytokine release syndrome (CRS) occurred in 11 (68.8%) patients, all of whom were grade 1. Only one patient experienced CAR-T-cell-related encephalopathy syndrome (CRES), manifesting as distal muscle weakness of the bilateral upper limb, and he recovered completely after corticosteroids treatment. Twelve (75.0%) patients achieved a response after CNCT19 infusion, with a complete response (CR) rate of 37.5%. The ORR and CR rate at 3 months was 62.5% and 31.3%, respectively. Two patients with ongoing partial remission underwent allogeneic hematopoietic stem-cell transplantation, and both of them died of progressive disease at 6 months and 11 months post CNCT19 infusion, respectively. As of July 5, 2022, the median follow-up from CNCT19 infusion to the data-cutoff date was 44.5 months. The median progression-free survival and overall survival were 6.5 (95% CI 1.0 to NA) months and 12.7 (95% CI 2.9 to NA) months, respectively. Six (37.5%) patients remained alive by data cut-off. Conclusions: CNCT19 cells exhibited comparable efficacy and favorable safety in patients with R/R DLBCL and FL3b. A phase 2 clinical trial (NCT04586478) of administrating CNCT19 in R/R large B-cell lymphoma and high-grade B-cell lymphoma is underway.

Cell of origin is not associated with outcomes of relapsed or refractory diffuse large B cell lymphoma.

Activated B cell (ABC) type diffuse large B cell lymphoma (DLBCL), double hit lymphoma (DHL) and double expressor lymphoma (DEL) have poor outcomes to frontline R-CHOP but impact of these molecular features on outcomes of relapsed/refractory (R/R) disease is not well-characterized. We evaluated the association of diagnostic cell of origin (COO), double hit and double expressor status with overall survival after first relapse in DLBCL patients who were enrolled into the Molecular Epidemiology Resource (MER) cohort. COO was available from immunohistochemistry (IHC) using Hans criteria or gene expression profiling (GEP) (Nanostring) on the diagnostic FFPE biopsy. Of 373 pts with R/R DLBCL, 278 had COO by IHC: 152 were GCB, 107 were non-GCB. One hundred and fourty had COO by GEP: 44 were ABC, 65 were GCB and 13 were unclassifiable. Nineteen out of 163 (12%) were DHL; 30 out of 135 (22%) had DEL. COO, either by IHC (2years OS GCB: 45% [CI95 : 38-54] vs. non-GCB: 44% [CI95 :36-55], p>0.05) or GEP (2years OS ABC: 42% [CI95 : 29-59] vs. GCB: 40% [CI95 : 30-54], p>0.05), was not associated with difference in OS. DHL (2years OS 16 [CI95 :6-45] vs. 45% [CI95 : 34-59], p<0.01) and DEL (2years OS 33% [CI95 : 20-56], vs. 50% [CI95 : 41-60], p<0.05) had lower OS than non-DHL and non-DEL/non-DHL counterparts, respectively. COO by IHC or GEP was not associated with OS in R/R DLBCL while DHL and DEL were adverse prognostic markers in DLBCL at first relapse.

Enhanced lipid metabolism confers the immunosuppressive tumor microenvironment in CD5-positive non-MYC/BCL2 double expressor lymphoma.

Lymphoma cells expressing CD5 (CD5+) confer inferior outcome of diffuse large B-cell lymphoma (DLBCL), especially in non–MYC/BCL2 double expressor (non-DE) patients. In tumor microenvironment, CD5+ non-DE tumor revealed increased proportion of immunosuppressive M2 macrophages and enhanced pathways related to macrophage activation and migration. In accordance to M2 activation, lipid metabolism was upregulated, including fatty acid uptake and fatty acid oxidation, which supplied energy for M2 macrophage polarization and activation. Meanwhile, CD36 expression was upregulated and strongly correlated to the proportion of M2 macrophages in CD5+ non-DE DLBCL. In vitro, a DLBCL cell line (LY10) overexpressing CD5 significantly increased M2 proportion in comparison with control when cocultured with peripheral blood mononuclear cells (PBMCs). The addition of metformin significantly decreased the M2 proportion and the CD36 expression level in the coculture systems, indicating that metformin could target altered lipid metabolism and decrease M2 macrophages in DLBCL, especially in CD5+ non-DE lymphoma. In conclusion, enhanced lipid metabolism and M2 macrophage activation contributed to the immunosuppressive tumor microenvironment and could be potential therapeutic targets in CD5+ non-DE DLBCL.

Expression of c-Myc, Bcl2, Bcl6, and Cyclin D1 in High-Grade B-Cell Lymphoma.

BackgroundHigh-grade B-cell lymphomas (HGBLs), with c-Myc, Bcl2, and/or Bcl6 rearrangement, are aggressive neoplasms with poor clinical outcomes. Cyclin D1 is a proto-oncogene that is generally expressed by mantle cell lymphoma, its variants, and many other neoplasms.AimThe aim of this study is to investigate the expression and frequency of cyclin D1 in HGBL and its association with double expressor and triple expressor lymphomas. A few pieces of research have been reported on the expression of cyclin D1 in triple-hit lymphoma, renaming it quadruple-hit lymphoma. In the present study, we also used immunohistochemical (IHC) stains to look at the expression of cyclin D1 in double expressor and triple expressor.MethodologyThis is a cross-sectional descriptive study involving 60 cases, including both double and triple expressors, diagnosed by using hematoxylin and eosin (H&E) staining with subsequent IHC stains. We analyzed the expression of cyclin D1 in double expressor and triple expressor.ResultsThe expression and frequency of cyclin D1 were interpreted in terms of positivity in double expressors and triple expressors. Cyclin D1 positivity was observed in three (5%) cases of double expressors and two (3.33%) cases of triple expressors. Overall, five (9%) cases of HGBL were positive for cyclin D1.ConclusionThis study showed a very low frequency of cyclin D1 expression in double and triple expressor lymphomas. However, a few cases of HGBL showed expression of cyclin D1 and were not limited to only mantle cell lymphoma and its variants.

623MO Machine learning-based prediction of germinal center, MYC/BCL2 double protein expressor status, and MYC rearrangement from whole slide images in DLBCL patients

Diffuse Large B-Cells Lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma in adults (30-40%). In the 2016 World Health Organization (WHO), DLBCL are classified into 3 molecular subtypes according to cell of origin (COO), germinal-center, activated B-cell like and unclassified, based on gene-expression profiling (GEP). In daily routine, COO classification is replaced by immunochemistry (IHC) stains using the Hans algorithm based on the expression of CD10, BCL6 and MUM1 proteins. In addition, co-expression of BCL2 and MYC proteins is of prognostic value and defines the double-protein expressors (DPE) subtypes, associated with worse prognosis.

DA-R-EPOCH versus R-CHOP in intermediate and high risk IPI diffuse large B-cell lymphoma, a randomized controlled trial

Background: Diffuse large B-cell lymphoma is a challenging disease in management. Although most patients are cured with the standard R-CHOP, one third of them remains refractory to this regimen. As prognosis of refractory disease is worse than primarily responding one, several trials investigated other more intense frontline regimens tailored based upon risk and biological characteristics. Patients &amp; Methodology: This is a prospective randomized trial investigating the more intensive DA-R-EPOCH regimen as frontline therapy in intermediate and high risk DLBCL patients in comparison to the standard R-CHOP regimen. We compared both regimens in these risk categories as well as undergoing a subgroup analysis according to cell of origin (Germinal center versus activated B cell) and according to BCL2 and C-myc expression (double expressor lymphoma). Toxicities in both arms have been analyzed according to common terminology criteria for adverse events (CTCAE). Results: In spite of being more toxic and complex, there was no significant improvement in DFS or response rate with DA-R-EPOCH. No significant benefit for DA-R-EPOCH over R-CHOP in both germinal center and activated B-cell DLBCL. Conclusion: Tailoring upfront treatment of DLBCL based upon risk classification or BCL2/c-myc expression remains an area of unanswered questions and warrants further investigations.

Smart Start: Rituximab, Lenalidomide, and Ibrutinib in Patients With Newly Diagnosed Large B-Cell Lymphoma.

Chemoimmunotherapy for patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) is largely unchanged for decades. Both preclinical models and clinical data suggest the combination of lenalidomide and ibrutinib may have synergy in DLBCL, particularly in the non-germinal center B-cell-like subset. We enrolled 60 patients with newly diagnosed non-germinal center B-cell-like DLBCL in this investigator-initiated, single-arm phase II trial of rituximab, lenalidomide, and ibrutinib (RLI) with the sequential addition of chemotherapy (ClinicalTrials.gov identifier: NCT02636322). Patients were treated with rituximab 375 mg/m2 intravenous once on day 1, lenalidomide 25 mg once per day on days 1-10, and ibrutinib 560 mg once daily continuously of each 21-day cycle (RLI). After two cycles, standard chemotherapy was added to RLI for six additional cycles. The primary end points were overall response rate (ORR) after two cycles of RLI alone and complete response rate after completion of RLI with chemotherapy. In evaluable samples, circulating tumor DNA and DLBCL90 assays were performed. The median age was 63.5 years (range, 29-83 years) with 28% age 70 years or older. The revised international prognostic index identified 42% as high risk, and 62% were double expressor of MYC and BCL2 protein. The ORR after two cycles of RLI was 86.2%, and the complete response rate at the end of RLI-chemotherapy was 94.5%. With a median follow-up of 31 months, the progression-free survival and overall survival were at 91.3% and 96.6% at 2 years, respectively. Smart Start is the first study, to our knowledge, to treat newly diagnosed DLBCL with a targeted therapy combination before chemotherapy. RLI produced a high ORR, and RLI with chemotherapy resulted in durable responses. This establishes the potential for developing biologically driven and noncytotoxic first-line therapies for 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

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.

P1190: OUTCOMES BY BCL2 AND MYC EXPRESSION AND REARRANGEMENTS IN UNTREATED DIFFUSE LARGE B-CELL LYMPHOMA FROM THE POLARIX TRIAL

Background: Overexpression of BCL2 and MYC, and translocation of MYC, BCL2, and BCL6, are associated with poorer outcomes in patients with diffuse large B-cell lymphoma (DLBCL; Horn et al. Blood 2013). We previously reported progression-free survival (PFS) from POLARIX in subgroups of patients with DLBCL receiving Pola-R-CHP or R-CHOP, including patients with double expressor lymphoma (DEL; favoring Pola-R-CHP: hazard ratio [HR] 0.64, 95% confidence interval [CI] 0.42–0.97), and double- or triple-hit lymphoma (DHL/THL; favoring R-CHOP: HR 3.81, 95% CI 0.82–17.64) (Tilly et al. NEJM 2022). Aims: This is a prespecified exploratory analysis, to further analyze immunohistochemistry (IHC) expression status of BCL2 and MYC, and rearrangements (R) of BCL2, BCL6 and MYC as independent prognostic markers. The prognostic impact of DEL, and BCL2 and MYC overexpression within treatment arms was also explored. Methods: BCL2 and MYC protein expression were assessed by IHC and identified as IHC+ (≥50% [BCL2]/≥40% [MYC]) or IHC−; MYC-R, BCL2-R, and BCL6-R were detected by fluorescence in situ hybridization (Tilly et al. NEJM 2022). All patients provided informed consent. Pola-R-CHP is an investigational combination. Exploratory multivariate Cox regression models were adjusted for treatment, stratification factors (International Prognostic Index, bulky disease, geographic region), age >60 years, cell of origin, and biomarker evaluated, as appropriate. Results: The prevalence, univariate HR, and 2-year PFS estimates of BCL2+/MYC+ and BCL2-R/MYC-R/BCL6-R subgroups are presented (Table) except for BCL6-R, because all four PFS events in this subgroup were with Pola-R-CHP. Multivariate analyses results for Pola-R-CHP vs R-CHOP in patients with BCL2+ (HR 0.60, 95% CI 0.43–0.86) and those with MYC+ (HR 0.63, 95% CI 0.45–0.89) were similar to results of univariate analyses. Multivariate analyses of other subgroups were not performed due to the low patient number with BCL2-R/MYC-R/BCL6-R. While patients with DEL treated with Pola-R-CHP had improved PFS vs patients treated with R-CHOP (HR 0.64, 95% CI 0.42–0.97), the prognostic impact of DEL vs non-DEL was identified in the R-CHOP arm (univariate HR 1.53, 95% CI 1.06–2.21; multivariate HR 1.29, 95% CI 0.88–1.91) vs the Pola-R-CHP arm (univariate HR 1.10, 95% CI 0.72–1.69; multivariate HR 1.42, 95% CI 0.89–2.28). Similarly, patients with BCL2+ had inferior PFS vs patients with BCL2– in the R-CHOP arm (univariate HR 1.96, 95% CI 1.31–2.93; multivariate HR 1.74, 95% CI 1.14–2.66); however, no prognostic difference was detected in the Pola-R-CHP arm (univariate HR 1.30, 95% CI 0.85–2.01; multivariate HR 1.56, 95% CI 0.99–2.47). No prognostic impact of MYC+ vs MYC– was detected in either arm (R-CHOP: univariate HR 1.17, 95% CI 0.77–1.77; multivariate HR 1.00, 95% CI 0.65–1.55; Pola-R-CHP: univariate HR 0.83, 95% CI 0.54–1.27; multivariate HR 0.91, 95% CI 0.58–1.42). Image:Summary/Conclusion: Multivariate analyses support the benefit of Pola-R-CHP in patients with BCL2+ and MYC+ DLBCL. The poor prognostic impact associated with DEL, which was mainly driven by BCL2+, appears reduced in Pola-R-CHP- vs R-CHOP-treated patients.

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.