Leonard, John P.

Abstract Progression of disease within 24 months of initial immunochemotherapy (POD24) is a negative prognostic factor for patients with follicular lymphoma (FL). There is no standard treatment after POD24. Assembling an academic-based cohort from the Lymphoma Epidemiology of Outcomes Consortium for Real World Evidence, we evaluated patterns of care and outcomes for 220 patients with FL with POD24 and retained FL histology. Therapy after POD24 was heterogeneous, with no treatment category accounting for >25% of the total. Among patients initially treated with bendamustine-rituximab, rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP) was the predominant second-line choice (48%). Among patients initially treated with R-CHOP, aggressive salvage therapy was the predominant second-line choice (38%). Overall response rate to therapy after POD24 was 64% (95% confidence interval [CI], 56-70); complete response rate was 39% (95% CI, 32-46). The median event-free survival for therapy after POD24 was 9.8 months (95% CI, 7.3-12.1); 5-year overall survival (OS) was 71% (95% CI, 65-78). OS was inferior for patients aged >70 years (hazard ratio [HR], 2.31; 95% CI, 1.27-4.20) and those with high-risk FL International Prognostic Index scores at diagnosis (HR, 2.10; 95% CI, 1.23-3.60). No treatment category stood out with more favorable results. Cause of death was predominantly lymphoma related. Patients with follicular histology at their POD24 event had a low cumulative incidence of transformation (1.1% at 5 years). Our study is among the largest cohorts describing contemporary patterns of care for patients with POD24, providing a focused data set useful for interpreting and designing prospective clinical trials in this population.

7012 Background: DLBCL with expression of MYC and BCL2 (double expressor lymphoma, DEL), has an adverse prognosis. Venetoclax, an inhibitor of BCL2, was previously studied in combination with R-CHOP. A051701 is a phase II/III randomized trial of chemoimmunotherapy +/- venetoclax in DEL and double hit lymphoma cohorts. Here we report initial phase II results from the DEL cohort. Methods: Patients (pts) age ≥ 18 years (y) with untreated DEL were randomized 1:1 to R-CHOP (Arm 1) or R-CHOP-venetoclax (Arm 2). DEL was defined as MYC expression ≥40% and BCL2 expression ≥50%, without double hit cytogenetics. Enrollment was based on local pathology results that were centrally confirmed. Venetoclax 800 mg was given orally days 4-8 of cycle 1 and days 1-5 of subsequent cycles for up to 6 cycles. All cycles were supported by GCSF or peg-GCSF. The primary endpoint was progression-free survival (PFS) with 84% power to detect a HR of 0.518 corresponding to 2y PFS rate of 65% in Arm 1 and 80% in Arm 2 (1-sided α=0.20). Results: 119 DEL pts were enrolled: 60 Arm 1; 59 Arm 2. Analyses were performed for the modified intent-to-treat population, defined as eligible pts with confirmed DEL histology (n=113; 56 Arm 1, 57 Arm 2). Median age was 64 y (range 22-85); baseline demographic factors were well balanced except for advanced stage (more common in Arm 1; (77% vs 60%, p=0.051). Most pts were non-germinal center B cell-like by immunohistochemistry (Arm 1 72%, Arm 2 58%), high-intermediate/high risk IPI (Arm 1 54%, Arm 2 51%) and ECOG performance status 0-1 (Arm 1 95%, Arm 2 86%). BCL2 rearrangements were detected in 25% and 33% of pts on Arm 1 and Arm 2, respectively. Most pts completed therapy per protocol (84% Arm 1, 75% Arm 2). Median follow up is 27 months (m). No difference in PFS was observed with 12-m PFS estimates of 77% in Arm 1, 76% in Arm 2 [HR = 0.98 (95% CI: 0.48 – 2.01), p=0.95]. The end of treatment (EOT) overall and complete response rates among patients with an EOT assessment were 87.5% and 70% in Arm 1, and 90% and 82% in Arm 2. Overall survival (OS) was not statistically significantly different with 12-mo OS estimates of 94% in Arm 1 and 79% in Arm 2 [HR = 1.27 (95% CI: 0.57 – 2.79), p=0.56]. Grade ≥3 adverse events (AEs) occurred more frequently in Arm 2 (42% vs 76%). The most commonly increased grade ≥3 AEs included neutropenia (20% vs 47%), anemia (4% vs 25.5%), thrombocytopenia (5.5% vs 24%), febrile neutropenia (7% vs 16%) and fatigue (0% vs 11%). No grade 5 AEs on treatment were reported on Arm 1, and 3 were reported on Arm 2 (lung infection and sudden death NOS, both possibly related; respiratory failure, unlikely related). Conclusions: Adding venetoclax to R-CHOP in DEL pts did not improve PFS and resulted in increased toxicity. The study did not meet its primary endpoint in phase II, and so did not proceed to phase III. Clinical trial information: NCT03984448 .

Abstract Although initial therapy of mantle cell lymphoma (MCL) is not standardized, bendamustine plus rituximab (BR) is commonly used in older patients. Rituximab (R) maintenance after induction is often used. Thus, the open-label, randomized phase 2 ECOG-ACRIN Cancer Research Group E1411 trial was designed to test 2 questions: (1) does addition of bortezomib to BR induction (BVR) and/or (2) addition of lenalidomide to rituximab (LR) maintenance improve progression-free survival (PFS) in patients with treatment-naïve MCL? From 2012 to 2016, 373 previously untreated patients, 87% aged ≥60 years, were enrolled in this trial. At a median follow-up of 7.5 years, there is no difference in the median PFS of BR compared with BVR (5.5 vs 6.4 years; hazard ratio [HR], 0.90; 90% confidence interval [CI], 0.70-1.16). There were no unexpected additional toxicities with BVR treatment compared with BR, with no impact on total dose/duration of treatment received. Independent of the induction treatment, addition of lenalidomide did not significantly improve PFS, with median PFS in R vs LR (5.9 vs 7.2 years; HR, 0.84; 90% CI, 0.62-1.15). Most patients completed the planned 24 cycles of LR at the scheduled dose. In summary, adding bortezomib to BR induction does not prolong PFS in treatment-naïve MCL, and LR maintenance was not associated with longer PFS compared with R alone after BR. Nonetheless, the >5-year median PFS outcomes in this prospective cooperative group trial indicate the efficacy of BR followed by R maintenance as highly effective initial therapy for older patients with MCL. This trial was registered at www.clinicaltrials.gov as #NCT01415752.

Abstract Although it is evident that standard-dose whole-brain radiotherapy as consolidation is associated with significant neurotoxicity, the optimal consolidative strategy for primary central nervous system lymphoma (PCNSL) is not defined. We performed a randomized phase 2 clinical trial via the US Alliance cancer cooperative group to compare myeloablative consolidation supported by autologous stem cell transplantation with nonmyeloablative consolidation after induction therapy for PCNSL. To our knowledge, this is the first randomized trial to be initiated that eliminates whole-brain radiotherapy as a consolidative approach in newly diagnosed PCNSL. Patients aged 18 to 75 years were randomly assigned in a 1:1 manner to induction therapy (methotrexate, temozolomide, rituximab, and cytarabine) followed by consolidation with either thiotepa plus carmustine and autologous stem cell rescue vs induction followed by nonmyeloablative, infusional etoposide plus cytarabine. The primary end point was progression-free survival (PFS). A total of 113 patients were randomized, and 108 (54 in each arm) were evaluable. More patients in the nonmyeloablative arm experienced progressive disease or death during induction (28% vs 11%; P = .05). Thirty-six patients received autologous stem cell transplant, and 34 received nonmyeloablative consolidation. The estimated 2-year PFS was higher in the myeloablative vs nonmyeloablative arm (73% vs 51%; P = .02). However, a planned secondary analysis, landmarked at start of the consolidation, revealed that the estimated 2-year PFS in those who completed consolidation therapy was not significantly different between the arms (86% vs 71%; P = .21). Both consolidative strategies yielded encouraging efficacy and similar toxicity profiles. This trial was registered at www.clininicals.gov as #NCT01511562.

AbstractTo address the current and long‐term unmet health needs of the growing population of non‐Hodgkin lymphoma (NHL) patients, we established the Lymphoma Epidemiology of Outcomes (LEO) cohort study (NCT02736357; https://leocohort.org/). A total of 7735 newly diagnosed patients aged 18 years and older with NHL were prospectively enrolled from 7/1/2015 to 5/31/2020 at 8 academic centers in the United States. The median age at diagnosis was 62 years (range, 18–99). Participants came from 49 US states and included 538 Black/African‐Americans (AA), 822 Hispanics (regardless of race), 3386 women, 716 age <40 years, and 1513 rural residents. At study baseline, we abstracted clinical, pathology, and treatment data; banked serum/plasma (N = 5883, 76.0%) and germline DNA (N = 5465, 70.7%); constructed tissue microarrays for four major NHL subtypes (N = 1189); and collected quality of life (N = 5281, 68.3%) and epidemiologic risk factor (N = 4489, 58.0%) data. Through August 2022, there were 1492 deaths. Compared to population‐based SEER data (2015–2019), LEO participants had a similar distribution of gender, AA race, Hispanic ethnicity, and NHL subtype, while LEO was underrepresented for patients who were Asian and aged 80 years and above. Observed overall survival rates for LEO at 1 and 2 years were similar to population‐based SEER rates for indolent B‐cell (follicular and marginal zone) and T‐cell lymphomas, but were 10%–15% higher than SEER rates for aggressive B‐cell subtypes (diffuse large B‐cell and mantle cell). The LEO cohort is a robust and comprehensive national resource to address the role of clinical, tumor, host genetic, epidemiologic, and other biologic factors in NHL prognosis and survivorship.

Introduction Survival rates for people with mantle cell lymphoma (MCL) have improved in recent years. Among the potential factors accounting for this improvement is the approval of multiple new therapies over the past two decades, including bortezomib, bendamustine, ibrutinib, lenalidomide, acalabrutinib, and zanubrutinib. We hypothesized that the availability of multiple agents with non-overlapping mechanisms of action would result in significant improvements in overall survival following first-line therapy. Methods Patients diagnosed with MCL between 2002 and 2017 were identified using the SEER-Medicare linked database. Selected patients were &gt;65 years of age at the time of diagnosis with MCL. Lines of therapy were determined using billing codes, with inpatient/outpatient claims used for traditional agents and Medicare Part D dataset used for oral agents. Next lines of therapy were defined based on claims for new anticancer agents separated from the end of the prior line by some certain number of days. Sensitivity analyses were performed varying the number of days between therapies. Overall survival (OS) was defined as initiation of initial therapy to death, while OS2 was defined as time from initiation of second-line therapy to death. Time to next therapy 1 (TTNT1) was defined as time from start of first-line therapy to death or start of second-line therapy, whichever came first. Cox models and Kaplan-Meier (KM) survival curves were generated for time-to-event analyses. Analyses were stratified by categories of years of first- and second-line therapies corresponding to eras of key drug approvals (e.g., 2002-2005, 2006-2009, 2010-2013, &gt;2013). Results In total, 4,832 patients were included, among whom 3,840 patients (79.5%) had claims for first-line regimens and 1,648 (34.1% of total and 42.9% of patients with first-line regimens) had second-line regimens. Of the 4,832 patients, the majority were male (67.4%), White (94.6%), and non-Hispanic (94.7%), with good performance status (74.8%) and a Charlson Comorbidity Index &lt;2 (64.8%). The median age at diagnosis was 75 (IQR 70-81). Patients with first- and/or second-line regimens did not differ significantly from the entire population of 4,832 patients with MCL in terms of baseline characteristics. In the first-line setting, use of bendamustine-rituximab (BR) increased from 2.3% of patients treated in 2006-2009 to 49.5% in 2014-2017. Similarly, use of single-agent BTK-inhibitors (BTKi) increased from nonexistent in patients treated in 2010-2013 to 13.8% in 2014-2017. In the second-line setting, use of single-agent BTKi similarly increased from 2.6% of those treated in 2010-2013 to 44.9% in 2014-2017. Median OS for the 3,840 patients with fist-line regimens was 4.4 years (95% CI, 4.1-4.5); median OS for those receiving first-line therapy in 2002-2005 was 3.5 years (3.1-3.9), compared to 3.7 (3.4-4.0), 4.5 (4.2-5.0), and not reached (4.8-NR) among those treated in 2006-2009, 2010-2013, and 2014-2017, respectively. Patients treated in 2014-2017 had significantly improved OS compared with those in 2002-2005 (log rank p&lt;0.0001). Median TTNT1 overall was 2.5 years (2.4-2.6); median TTNT1 was 3.2 years (2.9-3.5) vs 2.3 years (2.1-2.6) for patients who received first-line therapy in 2014-2017 compared to 2002-2005 (log rank p&lt;0.0001) ( Figure A). In addition, there was a significant difference across KM curves for OS2 stratified by categories of years of second-line therapy, with median OS2 of 2.5 (2.0-3.2) in patients treated in 2014-2017 compared to median OS2 of 2.1 (1.7-2.5) in 2010-2013 ( Figure B). Discussion In this analysis, we observed improvements survival of MCL patients over time, along with similar improvements in outcomes following first-line therapy, which may correlate with increased BR and BTKi use as first-line agents. Unexpectedly, improvements in survival following first-line therapy were considerably more modest. Potential explanations include lack of data from recent years during which we expect continued increased utilization of oral therapies vs unique impact of repeated therapies in the elderly. Overall, these data support the need for ongoing development of first- and subsequent-line therapies in MCL.

Introduction: AutoHCT is an effective therapy for patients (pts) with DLBCL who are refractory or relapse following first-line chemotherapy, but long term outcomes remain suboptimal. The BTK inhibitor ibrutinib has shown promising activity in pts with ABC-DLBCL (Wilson et al, Nat Med 2015). In 2016 we launched a randomized phase III clinical trial to evaluate the addition of ibrutinib to AutoHCT as part of conditioning and as consolidation therapy for pts with relapsed/refractory ABC-DLBCL. Patients and Methods: Following assessment of open-label treatment in a safety cohort of 6 pts, we randomly assigned pts with chemotherapy-sensitive persistent or relapsed ABC-DLBCL to receive ibrutinib 560 mg [Arm A] or placebo [Arm B] concurrently with conditioning on days -6 to -1 of AutoHCT (Cycle 1). Following count recovery and resolution of acute toxicities, pts continued ibrutinib 560 mg in Arm A or placebo in Arm B for 12 additional 28-day cycles. Crossover to Arm A using single agent ibrutinib was allowed for pts progressing on Arm B. Central pathology review was performed for disease confirmation and subtype assignment. Initially, ABC subtype assignment was performed using the Nanostring Lymphoma Subtyping Test (LST) but the study was amended to use the IHC-based Hans classifier for non-GCB on 8/15/19. Other key eligibility criteria included receipt of no more than 3 prior regimens, no active CNS involvement, no need for long-term anticoagulation, and no prior progression on Ibrutinib. Pts were stratified by time to relapse (&lt;=12 mos vs &gt;12 mos), type of conditioning (BEAM or CBV) and prior ibrutinib use. The original design required 296 patients with 82% power to detect a difference in 2-year progression-free survival (PFS) rates of 67% vs. 50% with a two-sided alpha of 0.05. A revised statistical design allowed an interim futility analysis to be conducted after 40 pts were enrolled and followed for 2 years. Even though the study met criteria to continue accrual to a target of 160 pts, we decided to close it early due to declining accrual on 12/20/2022. We hereby present the primary analysis of the evaluable patients enrolled (data as of 07/17/2023). Results: Between 2/6/17 and 8/24/18, we screened 255 pts but enrolled only 34 (13%) largely due to long assay turnaround times and performance characteristics with the LST. Following the switch to the IHC-based Hans classifier (after 8/15/19), 60 out of 110 pts screened were enrolled (54%) in line with our a priori expectation. In total, 45 pts were randomized to Arm A vs. 43 to Arm B, with 39 and 38, respectively, being evaluable for the primary endpoint at this time. Median age was 61 years (range 20-75 years), median number of prior lines of therapy was 2, 46% of the pts were female, 21% were refractory or had early relapse, 94% were planned to receive BEAM conditioning. Overall, 87% of pts in Arm A and 88% in Arm B underwent conditioning while 70% and 67% respectively, started maintenance therapy. The median number of cycles received was 6 in Arm A vs. 5 in Arm B. The primary endpoint of 2-year PFS was 57.6% (95% CI: 42.1%, 78.8%) in Arm A vs. 40.8% (95% CI: 26.5, 62.8%) in Arm B (HR=0.54; 95% CI: 0.26, 1.10; log-rank p = 0.087). Median PFS was 26.5 months (95% CI: 10.2, not reached [NR]) in Arm A vs. 8.1 months (95% CI: 5.4, NR) in Arm B. Only one pt crossed over to Arm A after progression on Arm B. The most common grade 3-4 AEs in each of the arms were: neutropenia (A: 14%, B: 14%), febrile neutropenia (A: 11%, B: 9%), and thrombocytopenia (A: 11%, B: 7%). Rates of any grade atrial fibrillation were similar between arms (12.8% in Arm A vs. 10.5% in Arm B); one patient had grade 3 and one patient had grade 4 atrial fibrillation, both in Arm B. Six pts had reported grade 5 events (Arm A: 2 sepsis, 1 COVID-19, 1 respiratory failure and 1 disease progression and Arm B: 1 disease progression) but only one grade 5 event (sepsis, Arm A) was deemed probably related to treatment. Conclusions: Despite an early high rate of screen failures and declining accruals due to competition with CAR-T cell therapy, the primary analysis suggests that ibrutinib with and following AutoHCT in relapsed/refractory ABC-DLBCL is well-tolerated and may improve PFS in this high-risk patient population. This trial was supported by: U10CA180821, U10CA180882, U24CA196171; U10CA180820, UG1CA233234 (ECOG-ACRIN); U10CA180868 (NRG); U10CA180888 (SWOG) ClinicalTrials.gov Identifier: NCT02443077 https://acknowledgments.alliancefound.org

Introduction: Despite governmental and industry-sponsored efforts, clinical trial participation among rural residents and racial and ethnic minorities remains low. The NIH Revitalization Act of 1993 directed the NIH to establish guidelines for inclusion of women and minorities in clinical research. In 2015, the Food and Drug Administration launched an action plan to improve the quality of demographic subgroup data collection, identify barriers to enrollment, employ strategies to increase participation, and promote transparency of related data. However subsequent studies (Green et al. Health Aff. March 2022, Kanapuru et al. Blood Advances. March 2022.) showed no improvement in participation of racial minorities, including Blacks and Hispanics since this plan was enacted. Various complex system- and individual-based factors, including lack of clinical trial availability; lack of diversity in the investigator work force; scant patient and provider awareness of clinical trials; lack of trust in the health care system; and issues with access to care-often driven by financial, geographic, or social constraints (Allison et al. Cureus. Apr 2022.), and stringent eligibility criteria are deemed responsible. The Leukemia & Lymphoma Society (LLS) IMPACT (Influential Medicine Providing Access to Clinical Trials) research grant strives to bridge this unrelenting care gap. Methods: The LLS IMPACT program includes a 5-year research grant which was launched in 2021. The IMPACT grants support the establishment of clinical trial networks involving academic cancer centers (“Hubs”) linked to community clinics and oncology centers (“Spokes”). The program's overall goal is to provide patients access to trials through participation at the community sites. Initially, 3 institutional sites were selected to participate. These institutions had unique and tailored strategies to improve engagement of underrepresented patients, including black, indigenous, people of color, Hispanic, Latina/Latino, and people from rural communities in vastly different climates and local cultures. The IMPACT grant expanded to encompass 4 additional sites given the imminent needs and clamor of the hematology clinical trials community (Figure 1A). The catchment areas and strategies employed at each institution are summarized in the table (Figure 1B). Results: At the start of the grant period, focus was on building clinical research infrastructure and opening non-interventional clinical trials to teach personnel about clinical research and create relationships with patients. Other programs such as webinar series, tumor boards, technological advancements, and educational workshops were also established to enhance engagement among physicians, match patients to clinical trials, and to provide clinical trial education to potential patients. One trial that has seen early success is the CHIVE IMPACT trial, a non-interventional registry and biorepository which has enrolled 24 patients at a rural and underserved site as of July 2023. The purpose of CHIVE is to enroll patients who have clonal hematopoiesis (CH) or are at risk of CH and follow prospectively in efforts to understand risk of progression and potential for early intervention. The Universal Protocol is another biorepository trial which has more than tripled its enrollment number at a community site between 2021 and 2022. Of the 63 patients enrolled in 2022, 66% of them identified as a race other than White. As our core goal is to increase access to interventional trials, we hope to bring industry sponsored phase II and phase III studies to underrepresented areas that serve a broad patient population. Lack of financial resources, lack of transportation and distance to trial sites, and residual distrust of the medical community (e.g., legacy of Tuskegee experiments) are barriers the grantees are focused on overcoming to enroll the intended populations into clinical trials. Conclusion: The innovative strategies employed to expand access to clinical trials for underrepresented population at the various institutions through the LLS's IMPACT research grant can be utilized during clinical trials design and implementation phases to improve generalizability of clinical trials in hematologic malignancies. In the third year of this program, 7 participating sites are engaging impactful strategies (Figure 1B) which will be reported at the end of the grant period.

Introduction The Ki-67 index has been previously shown to be prognostic, wherein the cut-off of 30% was associated with inferior survival outcomes (Determann O et al, Blood 2008) in newly diagnosed MCL patients (pts). However, this cut-off determination was made in pts treated with CHOP/R-CHOP as the first-line treatment, controlled only for MIPI, and predates the advent of novel agents. Short diagnosis to treatment interval (DTI ≤ 14 days) was recently shown to be prognostic in newly diagnosed MCL but its association with Ki-67 is unknown. We sought to determine the optimal Ki-67 cut-off in MCL and its prognostic relevance in the modern era. Methods This is a pooled analysis of 2 large datasets, one prospective (CALGB 50403) and one retrospective (MCL real world study [MCL-RWS]). CALGB is now part of the Alliance for Clinical Trials in Oncology. CALGB 50403 is a phase II randomized study wherein newly diagnosed MCL pts received intensive induction chemoimmunotherapy (IIC) followed by autologous transplant, and posttransplant rituximab. The MCL-RWS included adult pts (≥18 years [yrs]) with MCL treated from 2000 to 2017 at 12 participating US sites. Pts from sites in the MCL-RWS that enrolled on CALGB 50403 were excluded. Ki-67 was scored by central review in 10% increments in the CALGB 50403 and per institutional standard in the MCL-RWS. We assessed Ki-67 as a continuous variable and used a restricted quadratic spline fit to find an optimal cut-off. We looked at the associations between Ki-67 and other known/ established MCL prognostic markers including MIPI and DTI. The outcome parameters were PFS and OS. Time-to-event endpoints were evaluated by Kaplan-Meier and Cox proportional hazard methods. Results Among the 793 pts (n=666, MCL-RWS and n=127, CALGB 50403) in the pooled analysis, Ki-67 was available in 385 pts (311 from MCL-RWS and 74 from CALGB 50403). The median OS (mOS) and PFS (mPFS) in the entire cohort (n=793) was 11.8 years and 4.7 years, respectively. The two groups (gps), those with and without Ki-67 data, were well balanced including MIPI and DTI. The median age was 62 yrs (range, 32-88), 81% males, 94% with ECOG performance status (PS) 0-1 and 84% with stage 4. We found a Ki-67 cut-off of 50% to be optimal as the relative hazard of death rises after 50%. Pts in the Ki-67 &gt;50% gp had significantly higher proportion with short DTI (36% vs 17%, p&lt;0.001), ECOG PS ≥2 (12% vs 5%, p=0.02), elevated LDH (58% vs 39%, p=0.005), and MIPI ≥6.2 (38% vs 20%, p=0.007) compared to Ki-67 of ≤50%. Ki-67 &gt;50% was associated with significantly inferior PFS with a hazard ratio (HR) of 2.10 (95%CI 1.50-2.92) compared to Ki-67 ≤50% with a mPFS of 2.1 vs 5.3 yrs, respectively, regardless of the age (young [≤65 yrs], 2.6 vs 5.3 yrs or old [&gt;65 yrs], 1.1 vs 5.4 yrs) or receipt of IIC (2.2 vs 5.9 yrs). Figure 1 shows the statistically significant difference in PFS between the Ki-67 gps of ≤10%, &gt;10% to &lt;30%, ≥30 to ≤50%, and &gt;50%. Ki-67 &gt;50% remained prognostic for PFS in multivariable analysis (MVA) after adjusting for significant variables in univariable analysis (UVA) including short DTI, ECOG PS ≥2, stage 4, elevated LDH, and MIPI ≥6.2 with adjusted HR (aHR) 2.19, 95%CI 1.38-3.48, p &lt;0.001. Ki-67 &gt;50% was associated with significantly inferior OS with a HR of 2.10 (95%CI 1.33-3.32) compared to Ki-67 ≤50% with a mOS of 9.4 yrs vs not reached (NR), respectively, regardless of the age or receipt of IIC. Figure 2 shows the statistically significant difference in OS between the Ki-67 gps of ≤10%, &gt;10% to &lt;30%, ≥30 to ≤50%, and &gt;50%. Ki-67 &gt;50% was not prognostic for OS in MVA after adjusting for significant variables in the UVA (MIPI and sex), aHR 1.79, 95% CI 0.92-3.49, p=0.08. Similar findings were seen in multivariable analysis with Ki-67 &gt;30%, which showed no prognostic significance (aHR 1.46, 95%CI 0.82-2.58, p=0.19). Because of disparate datasets, we performed sensitivity analysis looking at the prognostic relevance of in individual datasets (CALGB 50403 and MCL-RWS) and found Ki67 &gt;50% was prognostic for PFS and OS in both of the datasets consistent with the primary analysis. Conclusions This study evaluating the optimal Ki-67 cut off for pts with newly diagnosed MCL in the modern era found that Ki-67 &gt; 50% was prognostic for PFS but not OS in MVA. A potential reason for the lack of prognostic relevance for OS in this more recent dataset is the availability of effective options at relapse. We also found that short DTI was associated with high Ki-67 gp which is a novel finding.