Citations

7075 Background: Hepatosplenic T-cell lymphoma (HSTCL) is a rare, aggressive peripheral T-cell lymphoma arising primarily from γδ T-cells. It carries a poor prognosis and resists conventional chemotherapy. Most reports on HSTCL are case-based. This study comprehensively analyzes a large cohort, evaluating treatment strategies and survival outcomes. Methods: This retrospective study included patients (pts) with pathologically confirmed HSTCL diagnosed between 2000-2024, consecutively seen at Mayo Clinic MN. Clinical, pathological, genomic, and treatment-related data were extracted when available. Descriptive statistics were used to summarize baseline characteristics. Time-to-event analyses, including Kaplan-Meier estimates, median overall survival (OS), and survival time estimates were conducted from the date of diagnosis. Results: A total of 20 patients with newly diagnosed HSTCL were included, with a median age of 57 years (range: 35-71). The cohort was predominantly male (70%) and non-Hispanic (93%). Molecular data was available for five patients, revealing abnormalities in STAT5B, MLL3 deletion, TP53, EZH2, TERT, and NF1 E291D . The median follow-up was 27.6 months (m) with a median OS of 17.6 m (95% CI: 11.2 - NA). First-line treatment was anthracycline-based in 68% of pts and non-anthracycline-based in 32%, with higher response rates in the latter group (50% vs.83%). Although non-anthracycline regimens showed a trend toward improved 3-year OS (100% vs. 29%) the difference was not statistically significant (p = 0.16). Achieving a complete response to first-line therapy was also associated with a trend towards a better 3-year OS compared to refractory disease (80% vs. 50%, p = 0.17). Most pts (79%) underwent hematopoietic stem cell transplant (HSCT), primarily allogeneic, with only one receiving autologous HSCT. First-line therapy before HSCT was evenly distributed between anthracycline (55%) and non-anthracycline (45%) regimens. HSCT recipients had significantly higher 3-year OS than non-recipients (83% vs. 33%, p = 0.017). Notably, the patient with a TP53 mutation has remained in remission for over a year post-allogeneic HSCT. Conclusions: HSTCL predominantly affects younger pts, with nearly half dying within a year. Allogeneic HSCT, rarely used in other NHL subtypes, improved survival. Non-anthracycline regimens and achieving CR trended toward better outcomes. Our study, leveraging a sizable cohort, highlights the need for targeted research and novel therapies to improve HSTCL management. Summary of survival outcomes in HSTCL. Characteristics Median OS (y) 3-Year OS (95% CI) 1.48 [0.93- NA] 46% [0.26 - 0.81] Transplant Transplant NA [NA - NA] 83% [0.58 - 1.00] No Transplant 1.02 [0.93 - NA] 33% [0.07 - 1.00] Treatment Anthracycline Based 1.02 [0.36 - NA] 29% [0.11 - 0.73] Non-Anthracycline Based 4.61 [NA- NA] 100% [1.00 - 1.00]

Introduction: Outcomes from multidisciplinary lymphoma tumor boards in the molecular era are limited, and the effects of transitioning to virtual formats during the COVID-19 pandemic are not well-documented. This study evaluates how the transition of the Mayo Clinic Lymphoma Tumor Board to a virtual format has impacted its effectiveness and operations. The board, part of the International Mayo Clinic Care Network (MCCN), involves case presentations, subspecialist reviews, and collaborative recommendations. Methods: The Mayo Clinic Lymphoma Tumor Board, an integral part of the Mayo Clinic Care Network (MCCN), conducted a comprehensive review of lymphoma cases from 2014 to 2024. The board's review process involves a structured approach including the presentation of clinical case details, radiology and hematopathology findings, proposed treatment options, relevant literature review, and discussions. From 2014 to 2024, the Mayo Clinic Lymphoma Tumor Board reviewed a total of 722 patients. The review process involves a multidisciplinary team, including physicians, pharmacists, clinical research associates, and trainees. Recommendations and changes related to radiology interpretation, pathologic diagnosis, and treatment approaches were documented and tracked prospectively. In March 2020, the board transitioned to a virtual format due to the COVID-19 pandemic. This shift allowed for remote participation and continued collaborative review while maintaining the board's structured approach and documentation practices. Results: In a total of 722 patients, changes in care were identified in 423 patients, including 287 with newly diagnosed lymphoma and 136 with relapse or refractory disease. Among those who experienced changes, 94 had diffuse large B-cell lymphoma, 49 had follicular lymphoma, 39 had marginal zone lymphoma, 36 had classical Hodgkin lymphoma, and 29 had mantle cell lymphoma. Prior to the COVID-19 pandemic, 431 patients were analyzed, with 217 (50.3%) experiencing changes. A total of 268 changes were documented among these patients. Changes in radiologic interpretation occurred in 9 patients (2.1% of 431 total patients). Pathologic diagnosis changes were noted in 42 patients (9.7%). Additional testing was recommended for 73 patients (16.9%), and clinical management was altered for 144 patients (33.4%). After transitioning to a virtual format, 291 patients were reviewed post-COVID, with 206 (70.8%) having recommended changes. The total number of change recommendations was 322, reflecting increases across all components compared to previous data, with adjustments for varying numbers of patients reviewed. Specifically, radiologic interpretation changes occurred in 21 patients (7.2%), pathologic diagnosis changes in 57 patients (19.6%), additional testing recommendations for 85 patients (29.2%), and clinical management alterations in 159 patients (54.7%). Conclusion: Transitioning to a virtual format in the Mayo Clinic Lymphoma Tumor Board's continued to demonstrate the effectiveness, with increased changes in diagnostic interpretations and clinical management. These results illustrate the potential of virtual tumor boards to improve collaborative decision-making and adapt to evolving clinical needs.

Introduction: Mantle cell lymphoma (MCL) is an uncommon B-cell non-Hodgkin lymphoma (NHL) Prognosis is highly variable due to underlying biological and molecular heterogeneity. The first-line (1L) treatment paradigm for MCL continues to evolve with increasing use of bruton tyrosine kinase inhibitors (BTKi) and decreasing use of autologous stem cell transplant (ASCT). TP53 alterations are associated with inferior outcomes in MCL. The aim of this retrospective study is to determine treatment strategies and clinical outcomes in MCL patients based on TP53 gene mutation status. Methods: Retrospective data were collected from 19 institutions in the United States from 1/1993 to 1/2024. We examined treatment patterns and outcomes among MCL patients >18 years of age with known TP53 mutation status by sequencing. Patients who did not receive treatment were excluded. The analysis was stratified based on presence of TP53 mutations. Systemic therapies were categorized as chemo-immunotherapy (CIT), non-chemotherapy (including monoclonal antibodies, lenalidomide, venetoclax, and novel agents on clinical trial), and regimens containing BTKi. The primary outcome was overall survival (OS) and secondary outcomes were progression free survival (PFS) and time to next treatment (TTNT). OS and PFS were estimated with the Kaplan-Meier method and log-rank tests were used to compare groups. Results: 645 patients were included in the study, with 468 men (72.6%) and median age was 64 years (range 30-89). 230/645 patients (35.7%) had a TP53 mutation, of which 182 (79%) were identified prior to 1L. While the male/female distribution was the same between the mutated and unmutated groups, median age at diagnosis and MIPI risk score was higher in the TP53 mutated group (age 65.9 vs 63.1 yrs, p= 0.015; MIPI 6.4 vs 6.1, p<0.001). TP53 unmutated patients had a median of 1 line of therapy vs. 2 for the mutated group (p<0.001, range 1-8). Blastoid histology and higher ki67 were also associated with the TP53 mutated group (p=0.045, 0.01 respectively) The median OS was 14.2 years for TP53 unmutated and 8.3 years for TP53 mutated patients (p<0.0001). PFS in 1L was 0.95 years in TP53 mutated compared to 2.02 years in TP53 unmutated group (p<0.0001). Selection of 1L therapeutic strategy was not associated with presence of TP53 mutation (Χ2 p= 0.21) although more patients in the TP53 unmutated group underwent ASCT (119/415 vs 38/230; Χ2 p=0.0006) TP53 mutation was associated with inferior survival compared to TP53 unmutated patients for CIT in 1L but the difference did not reach statistical significance when non-chemotherapy regimens and regimens containing BTKi were used. For CIT in 1L, 5 year OS was 78% [71-84%] for unmutated compared to 58% [48-67%] for the mutated group (p=0.0001 ). For non-chemotherapy regimens, 5 year OS for unmutated patients was 73% [52- 86%] compared to 52% [25-73%] for the mutated group (p=0.09). For regimens containing BTKi, 5 year OS for unmutated was 93% [81-97%] compared to 57% [28-78%] for mutated (p=0.07). Within the TP53 mutated group, there were no differences in any clinical outcomes between those receiving CIT, non-chemotherapy, or BTKi in 1L. While median OS appeared numerically longer in the BTKi group (14.4 yrs vs 8.8 yrs for CIT and 6.8 yrs for non-chemotherapy), the difference did not reach statistical significance (p=0.58). In contrast,TP53 unmutated patients who received CIT in 1L had better TTNT (p=0.0039) compared to those in non-chemotherapy and BTKi groups. There was no improvement in PFS (p=0.79) or OS (p=0.47). Conclusions To our knowledge this is the largest retrospective real world dataset of MCL treatment outcomes stratified by TP53 mutation. As in prior studies, TP53 mutation portends a worse prognosis in MCL compared to TP53 unmutated patients, but outcomes are better than historically reported. CIT in 1L was not associated with improved OS in either group. Irrespective of TP53 mutation status, incorporation of BTKi in first line was not associated with improved clinical outcomes. The gap in OS between TP53 mutated and unmutated MCL may be narrowing as treatment paradigms shift away from intensive induction chemotherapy and ASCT, and due to an increasing number of effective therapies for relapsed patients. Clinical trials of novel agents are needed to further improve the OS of TP53 mutated MCL patients.

Introduction: The treatment of older patients with advanced stage classical Hodgkin lymphoma (cHL) is challenging and outcomes remain poor compared to younger patients (pts). A subgroup analysis of older pts (aged ≥ 60 years) enrolled in the SWOG S1826 study showed the Nivolumab-AVD regimen was better tolerated and improved progression free survival (PFS) compared to concurrent brentuximab vedotin-AVD (Bv-AVD). The sequential administration of Bv before and after AVD chemotherapy (seq Bv-AVD-Bv) is a commonly used approach to minimize the toxicity of Bv-AVD in older pts based on the tolerability and efficacy shown in a phase II study (Evens, et al. J Clin Oncol 2018). There is limited data on clinical outcomes with seq Bv-AVD-Bv in the real-world setting. We report our multicenter study of sequential Bv-AVD-Bv administration in older patients with cHL. Methods: This retrospective study included a total of 40 older pts with cHL treated with sequential Bv-AVD-Bv in 6 cancer centers. Descriptive statistics were used to depict patient demographics and disease characteristics prior to treatment initiation. Responses to therapy were assessed using the Lugano criteria. Response evaluable patients were those who received at least one cycle of chemotherapy with AVD. PFS and overall survival (OS) were estimated using log-rank testing with the Kaplan Meier curves. Results: The majority (n=23, 57.2%) of patients were male; median age was 72.5 years (range, 57-86 years); 10 (25%) pts were Hispanic, and 18 (45%) pts were Caucasian; performance status by ECOG was 0-2 in 33 (82.5%) pts. In terms of disease characteristics 19 (47.5%) pts had cHL NOS, 10 (25%) had nodular sclerosing subtype; stage III/IV in 35 (87.5%), stage II in 5 (12.5%) pts; B- symptoms in 21 (52.5%); extranodal disease in 19 (47.5%), with bone marrow involvement in 10 (25%) pts. Among the 38 response-evaluable patients the ORR and CR rates were 97.4% and 71.1%, respectively. Bv dose reductions or interruptions were reported in 14 (35.9%) pts. Treatment discontinuation (Td) occurred in 16 (40%) pts. The most common any grade adverse events were hematological toxicities (HT) in 28 (70%) pts and peripheral neuropathy in 24 (60%) pts. Forty-five percent of patients experienced grade 3 or higher HT. The overall incidence of grade 2 or higher peripheral neuropathy was 15%. The main reasons for treatment discontinuation were toxicity (n=9) and disease progression (n=4). During treatment, 1 (2.5%) pt reported loss of basic activities of daily living (ADLs) and 5 (12.5%) had loss of instrumental ADLs (iADLs). G-CSF prophylaxis was used in most (n=33, 82.5%) pts. At a median follow up of 25.7 months (range, 2.6 - 58.9) the 2 years PFS was 62.6% (95% CI: 46.1-79.1) and the 2 years OS was 83.3% (95% CI: 67-99.6). On univariate analysis, the median PFS correlated with the depth of response (CR: not reached; PR: 11.4 months; SD/PD: 3.9 months; P=0.0001); and with treatment discontinuation (No Td: not reached; Td: 21.6 months; P=0.007). There was no correlation between age, sex, institution, B- symptoms, bone marrow involvement, ADL/iADLs, or disease stage with treatment discontinuation. Conclusion: Sequential Bv-AVD-Bv in older patients with cHL can help minimize the toxicity associated with the concurrent administration of Bv-AVD. This sequential approach has shown comparable efficacy in real-word setting as seen in clinical trials. Our findings suggest seq Bv-AVD-Bv remains a feasible option for older fit patients with cHL outside clinical trials. Further randomized studies in older cHL pts are needed.

Background: Polatuzumab vedotin (Pola) is an antibody drug conjugate targeting CD79b that incorporates the microtubule disrupting monomethyl auristatin E payload. Pola was approved in 2023 for the upfront treatment of diffuse large B cell lymphoma (DLBCL) in combination with rituximab, cyclophosphamide, doxorubicin, and prednisone (polaRCHP) based on the POLARIX trial. However, the activity of pola appears to vary based on DLBCL cell of origin (COO) subtype, with greater efficacy in activated B cell (ABC) DLBCL compared to germinal center B cell (GCB) DLBCL (Russler-Germain Blood 2023). When outcomes in POLARIX are stratified by COO, polaRCHP demonstrated progression free survival (PFS) and overall survival (OS) benefits over RCHOP in patients with ABC but not GCB subtype DLBCL (PFS HR 0.34 ABC vs 1.03 GCB, OS HR 0.27 ABC vs 1.64 GCB; Morschhauser ASH 2023 and FDA data). Most prospective studies of pola used gene expression to assess COO, which is not readily clinically available. This study aims to examine if COO subtype by Hans algorithm (based on CD10, BCL6, and MUM1 expression by immunohistochemistry) is predictive of pola responses and outcomes in patients with large B cell lymphoma (LBCL). Methods: We conducted a retrospective, multicenter observational study of adults with LBCL who received pola (monotherapy or in combination) from 2015-2024 with Hans algorithm COO data and response assessment available. Patients were stratified by receipt of pola in the frontline vs relapsed/refractory (R/R) setting. The primary endpoint was overall response rate (ORR) to pola-based treatment in GCB vs non-GCB subtypes. Secondary endpoints included complete response rate (CRR), PFS, and OS. For time to event endpoints, patients responding to pola who received CAR T or stem cell transplantation prior to progression were censored at time of cellular therapy. Demographics were summarized by descriptive statistics. Comparative and survival analyses used Chi squared/Fischer exact tests and Kaplan Meier analysis. Data cutoff was July 1, 2024. Results: 718 patients were included. Median follow-up was 15 months (interquartile range [IQR] 8-32). Median age at LBCL diagnosis was 66 years (IQR 56-74); 62% were men; 69 (10%) had double hit lymphoma (DHL); 129 (18%) had underlying low grade lymphoma. Pola was used in the frontline setting in 293 (41%) patients, of whom 139 (47%) had GCB vs 154 (53%) non-GCB COO. Of the 426 patients receiving pola for R/R LBCL (including one patient receiving pola retreatment), 224 (53%) had GCB vs 202 (47%) non-GCB COO. Among patients receiving pola-based regimens in the R/R setting (GCB vs non-GCB: pola monotherapy = 7% vs 4%, pola + R = 26% vs 26%, pola + BR = 55% vs 61%, pola + other = 12% vs 9%; p = 0.44), the ORR in GCB vs non-GCB LBCL was 36% vs 61% (p < 0.001), while CRR in GCB vs non-GCB was 17% vs 36% (p < 0.001). COO remained a significant component of logistic multivariate regression models of ORR (p < 0.001) and CRR (p < 0.001) when incorporating IPI at original LBCL diagnosis, histology, DHL status, and refractory status to frontline therapy. Despite this, no significant PFS or OS differences by COO were seen, potentially due to approximately 1/4 patients being censored due to receiving subsequent cellular therapy (e.g. CAR T) prior to progression. In patients receiving frontline pola-based regimens (of which 275 [94%] included an anthracycline), ORR and CRR were similar in GCB vs non-GCB (ORR 89% vs 88% p > 0.5; CRR 76% vs 77% p > 0.5). While PFS and OS were similar between COO groups in the frontline cohort, follow-up and cohort size were limited. Conclusion: Based on this real-world evidence, COO classification by Hans algorithm is a strong predictor of the activity of pola-containing therapy in R/R LBCL, with significantly higher ORR and CRR in patients with non-GCB compared to GCB COO LBCL. This aligns with the cumulative existing evidence. ORR and CRR to pola-containing therapy in the frontline setting did not differ significantly by COO subtype, but longer follow-up of larger cohorts is needed to clarify the predictive role of COO by Hans algorithm in this setting, especially considering the PFS advantage with polaRCHP in POLARIX was not associated with significant differences in ORR or CRR. Overall, clinicians should consider factoring COO subtype into treatment decisions regarding pola-containing regimens, and studies of pola-based therapies should stratify patients and report outcomes by COO subtype.

Background: In the ZUMA2 study, a higher peak chimeric antigen receptor (CAR) T cell expansion correlated with better outcomes in patients with relapsed/refractory (R/R) mantle cell lymphoma (MCL) receiving brexucabtagene autoleucel (brexu-cel). However, in clinical practice, peak CAR T cell expansion is not routinely assessed for. Since patients receive lymphodepleting agents prior to CAR T cell infusion, it is hypothesized that peak absolute lymphocyte count (ALC), which can be easily measured, in the first two weeks after CAR T cell infusion represents peak CAR T cell expansion. Our group previously showed that peak ALC was associated with response durability and outcomes in patients with R/R large B-cell lymphoma receiving axicabtagene ciloleucel. In this retrospective study, we assessed the association of peak ALC with clinical outcomes after brexu-cel infusion in patients with R/R MCL. Methods: Patients with R/R MCL who received brexu-cel between March 2020-March 2024 at Mayo Clinic were included in this analysis. Peak ALC was defined as maximum ALC value in the first 14 days after CAR T cell infusion. Progression-free survival (PFS) was defined as time from CAR T cell infusion to lymphoma relapse, progression, or death, and overall survival (OS) was defined as time from to CAR T cell infusion to death. The optimal cutoff point for peak ALC that correlated with PFS was determined by the log-rank method using the Cutoff Finder application, a computational method which fits Cox proportional hazard models to the dichotomized variable and survival. The optimal cutoff was the point with the most significant PFS split by log-rank test. Results: A total of 43 patients were identified. The median age at time of CAR T cell infusion was 68 years (IQR 58, 73). 34 (79%) were male, 28 (74%) had Ki-67 >30%, 14 (33%) had blastoid or pleomorphic histology, and 19 (44%) had TP53 mutation or deletion. Median number of prior lines of therapy was 3 (IQR 2, 4) and 13 (30%) received prior autologous stem cell transplant. 32 (74%) received bridging therapy prior to CAR T cell infusion. All patients received fludarabine plus cyclophosphamide for lymphodepletion. The best overall response rate was 88%, with a complete response rate of 84%. After a median follow-up of 25.6 months (95% CI 14.4-31.4), the median PFS and OS were 16.6 (95% CI 8.6-NE) and 35.1 (95% CI 24.5-NE) months, respectively. The incidence of cytokine release syndrome (CRS) was 95% (4.7% grade ≥3). The median time to initial CRS and maximum grade CRS onset was 4.5 days (IQR 1, 6.25) and 5.5 days (IQR 2.75, 7), respectively. The incidence of immune effector cell-associated neurotoxicity syndrome (ICANS) was 65% (18% grade ≥ 3). The median time to initial and maximum grade ICANS onset was 9 days (IQR 6, 11) and 10.5 days (IQR 7, 12), respectively. The median ALC at time of CAR T cell infusion was 0.03 x109/L (IQR 0.02, 0.05). Among 37 patients with identifiable ALC peaks, the median ALC peak was 0.84 (IQR 0.41, 2.45) and the median time to peak ALC was 12 days (IQR 9, 12). 6 patients had no identifiable peak ALC due to no frequent CBC differentials post CAR T cell infusion. A peak ALC of ≥0.45 × 109/L correlated significantly with PFS, with median PFS not reached for the group with peak ALC of ≥0.45 × 109/L (n=27) compared to 9.3 months for the group with peak ALC of <0.45 × 109/L (n=10) and a 1-year PFS rate of 68% vs 33% (p=0.02). OS was also significantly higher in patients with a peak ALC of ≥0.45 × 109/L (median OS not reached vs 11 months, 1-year OS rate of 84% vs 44%, p=0.01). The incidence of ICANS was significantly higher (74% vs 30%, p=0.02) in patients with a peak ALC of ≥0.45 × 109/L. Numerically, the group with peak ALC of ≥0.45 × 109/L had a later onset of initial and maximum grade ICANS, but the difference was not statistically significant. Peak ALC was not associated with ICANS severity. There was a trend towards higher incidence of CRS (100% vs 80%, p=0.07) and earlier CRS onset (3 vs 5 days, p=0.07) in the high peak ALC group. There was no difference in CRS severity. Conclusion: Peak ALC after CAR T cell infusion was significantly associated with better PFS and OS and higher incidence of ICANS in patients with R/R MCL receiving brexu-cel. Peak ALC may serve as a surrogate measure for peak CAR T cell expansion in routine practice, but confirmatory studies are needed. Larger studies are warranted to confirm the association of peak ALC with PFS, OS and toxicities in patients with R/R MCL receiving brexu-cel.

Background: Erdheim-Chester disease (ECD) manifests as multi-organ infiltration of clonal histiocytes with mutations primarily in the mitogen-activated protein kinase (MAPK) pathway. The revised classification of histiocytosis (2016) categorizes ECD with typical bilateral, symmetric osteosclerosis of the lower extremity long bones as classical (C) and as non-classical (NC) if otherwise. The clinical and biological significance of this classification is unclear. This study compared the clinical and genotypic findings of the 2 subtypes within a large cohort of ECD patients. Methods: We included patients seen at our institution since 1990 meeting the following criteria: A) had an ECD diagnosis based on the revised criteria by Haroche J, et al. (Blood 2020;135:1311-1318); B) completed whole-body imaging studies including long bones of the legs. Classification as C-ECD required symmetric osteosclerosis of the distal femur and/or proximal tibia/fibula. Results: A total of 145 patients were enrolled, comprising a male-to-female ratio of 2:1 (66.2% male). C-ECD was diagnosed in 77.2% of cases, and NC-ECD in 22.8%. The median age at diagnosis was similar with 58.5 years (range, 18-82) in C-ECD and 55 years (range, 20-81) in NC-ECD, (p=0.65). The most frequently affected systems included skeletal (81.4%), renal (60.0%), vascular (45.5%), cardiac (40.0%), central nervous (38.6%), sinus (37.2%), pulmonary (36.6%), and adrenal (32.4%). The numbers of organs involved were significantly higher in C-ECD compared to NC-ECD (median 5 vs 3, p<0.01). Higher rates of skeletal (100% vs. 18.2%, p<0.01), adrenal gland (37.5% vs. 15.2%, p=0.02), and sinus (44.6% vs. 12.1%, p<0.01) involvement were observed in C-ECD. Arginine vasopressin deficiency (AVP-D) was exclusively observed in C-ECD (20.7% vs. 0%, p<0.01). NC-ECD had a higher rate of cardiac involvement (69.7% vs. 31.3%, p<0.01). No significant differences were found in other systems. The overall median time between onset of the first symptoms/signs to diagnosis was 15 months with no significant difference between C-ECD and NC-ECD (17.5 vs. 12 months, p=0.18). The median time to diagnosis of ECD in patients with AVP-D was 38.5 months, compared to 12 months without AVP-D (p=0.09). Genetic testing was conducted in 86.2% of patients and B-Raf proto-oncogene (BRAF) alterations were identified in 59.2% of the tested cases. BRAFV600E was more prevalent in C-ECD (61.3% vs. 21.9%, p<0.01), whereas non-V600 mutations were more commonly found in NC-ECD (12.5% vs. 1.1%, p<0.01). There was no significant difference in the frequency of BRAF fusions. NC-ECD patients exhibited a higher rate of MAP2K1 mutations (25.0% vs. 5.4%, p<0.01). Other frequently mutated genes included KRAS (4.0%), NRAS (2.4%), and CSF1R (2.4%), although no significant difference was observed in their frequency between C-ECD and NC-ECD. Testicular involvement appeared to be more common in patients with MAP2K1 mutations (23.1% vs. 8%, p=0.08). Two patients with pathogenic CSF1R mutations both had central nervous system (CNS) involvement. Among C-ECD patients, BRAFV600E conferred a higher rate of CNS involvement (50.9% vs. 25%, p=0.01). No significant difference was observed in NC-ECD patients (71.4% vs 36%, p=0.09). Among NC-ECD cases, MAP2K1 mutations conferred a reduced risk of cardiac involvement (37.5% vs. 79.2%, p=0.03) and no such difference was observed in patients with C-ECD (40% vs 34.1%, p=0.79). The median numbers of organs involved in patients with BRAF, MAP2K1, and KRAS/NRAS mutations were 5, 3, and 3, respectively, with no significant difference. Conclusions: C-ECD affects more organs and more frequently involves bones, adrenal glands, and sinuses. AVP-D was exclusively observed in C-ECD. Conversely, NC-ECD showed a higher prevalence of cardiac involvement. BRAFV600E was more commonly identified in C-ECD, whereas non-V600 mutations and MAP2K1 mutations were more prevalent in NC-ECD. Among C-ECD patients, BRAFV600E was correlated with a greater likelihood of CNS involvement. Conversely, NC-ECD patients with MAP2K1 mutations had a reduced risk of cardiac involvement. This study highlights the distinct clinical and molecular features of C-ECD and NC-ECD, underscoring the importance of subclassifying ECD into classical and non-classical forms. Further studies are needed to explore differences in the clinical outcomes between the 2 forms.

Background Mantle cell lymphoma (MCL) is more common in males, with a male to female ratio of approximately 3:1. However, it is unclear whether disease characteristics and survival outcomes differ by sex. Additionally, the impact of race and ethnicity in MCL is understudied due to underrepresentation of minorities in clinical studies and trials. In this study, we utilized the National Cancer Database (NCDB) to examine patient and disease characteristics and survival outcomes of MCL by sex, race and ethnicity. Methods Patients diagnosed with MCL in 2004-2020 were identified from NCDB. Patient and disease characteristics were compared between groups using Chi-squared tests. Overall survival (OS) analysis was performed using the Kaplan-Meier method and the Cox proportional hazards model. Results A total of 35,135 patients was included. The median follow-up was 83.0 months (95% CI 81.9-84.1). 24,980 (71.1%) patients were male and 10,155 (28.9%) were female. Females had more elderly (age ≥65: 65.9% vs 59.0%; p<0.001), lower Charlson-Deyo Score (CDS ≥2: 7.0% vs 8.6%; p<0.001) and fewer stage III-IV diagnoses (80.5% vs 82.6%; p<0.001). Females were less likely to receive upfront treatment (80.7% vs 85.3%; p<0.001), treatment at academic centers (36.8% vs 40.9%; p<0.001) or transplant (11.0% vs 13.7%; p<0.001). Compared to males, females were more likely to live in metropolitan areas (83.7% vs 81.6%; p<0.001), had similar incomes, had more Medicare (60.4% vs 53.1%) and fewer private insurance (33.2% vs 38.6%; p<0.001). Female patients had better OS, with a median OS of 76.0 (95% CI 72.4-79.6) vs 67.8 months (95% CI 65.9-69.6; p<0.001). In the multivariable Cox model adjusting for age, race, ethnicity, CDS, stage, upfront treatment (vs surveillance or no treatment), facility (academic vs nonacademic), transplant, residence (metropolitan vs urban or rural) and insurance, female sex remained associated with superior OS (HR 0.84, 95% CI 0.793-0.890; p<0.001). For race, 32,399 (92.2%) patients were White, 1,465 (4.2%) were Black, 942 (2.7%) were others and 329 (0.9%) were unknown. Compared to White patients, Black patients had fewer elderly (52.9% vs 61.7%; p<0.001), higher CDS (≥2: 11.4% vs 7.9%; p<0.001), similar stage III-IV (80.7% vs 82.1%; p=0.276) and upfront treatment (84.7% vs 84.0%; p=0.074), were more likely to be treated at academic centers (50.6% vs 38.9%; p<0.001), were less likely to receive transplant (11.1% vs 13.0%; p=0.042), were more likely to live in metropolitan areas (91.0% vs 81.5%; p<0.001), had lower income, had more uninsured (4.4% vs 2.0%) and Medicaid (9.8% vs 3.7%) and fewer Medicare (47.4% vs 56.0%; p<0.001). Black and White patients had similar OS, with a median of 67.9 (95% CI 57.5-78.2) vs 69.6 months (95% CI 67.8 vs 71.3; p=0.697). In the multivariable Cox model, Black vs White race was not associated with OS (HR 1.086, 95% CI 0.952-1.240; p=0.219). For ethnicity, 31,717 (90.3%) patients were non-Hispanic, 1,894 (5.4%) were Hispanic and 1,534 (4.3%) were unknown. Hispanics had fewer elderly (51.3% vs 61.5%; p<0.001), lower CDS (≥2: 6.4% vs 8.2%; p=0.018), similar stage III-IV (81.2% vs 82.1%; p=0.467), were more likely to receive upfront treatment (86.0% vs 83.9%; p<0.001), more likely to be treated at academic centers (49.9% vs 39.5%; p<0.001), equally likely to receive transplant (13.0% vs 13.1%; p=0.943), more likely to live in metropolitan areas (95.4% vs 81.6%; p<0.001), had lower income, had more uninsured (9.6% vs 1.8%) and Medicaid (15.2% vs 9.6%) and fewer Medicare (40.3% vs 55.9%; p<0.001). Hispanics had better OS, with a median OS of 84.4 (95% CI 71.7-97.1) vs 70.5 months (95% CI 68.7-72.2; p<0.001). However, in the multivariable Cox model, Hispanic ethnicity was not associated with OS (HR 0.952, 95% CI 0.839-1.080; p=0.448). Conclusion This study is the first of its scale to demonstrate that female MCL patients have superior survival outcomes compared to males. It also demonstrated that neither Black race nor Hispanic ethnicity appears to be associated with worse survival outcomes. Despite its size, the NCDB is limited in the treatment information and disease characteristics it provides, including MIPI score, Ki-67, blastoid/pleomorphic morphology, and TP53 status. Thus, additional real-world dataset studies are needed to gain a deeper understanding of potential differences in sex, race and ethnicity with regards to disease characteristics and survival outcomes.

Introduction: Bispecific antibodies (BsAbs) epcoritamab (Epco) and glofitamab (Glofit) are approved in the US for the treatment of patients (pts) with relapsed or refractory (r/r) large B-cell lymphomas (LBCLs) based upon high response rates and manageable toxicity profiles reported in pivotal trials. However, data on outcomes for pts treated with BsAbs outside of clinical trials are limited. As such, we sought to investigate the safety and efficacy of Epco and Glofit for the treatment of pts with r/r LBCLs in real-world settings. Methods: We performed a retrospective study including 19 US centers evaluating pts with r/r LBCLs receiving commercially available Epco or Glofit between 2023 and 2024. Baseline characteristics and outcomes were extracted from medical records. Efficacy outcomes included overall response rate (ORR), complete and partial response (CR, PR) rates, progression-free survival (PFS) and overall survival (OS), analyzed using the Kaplan Meier method. Key safety outcomes included cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Results: As of May 31, 2024, a total of 209 pts with r/r LBCLs were treated with Epco (n=139) or Glofit (n=70). Median age at BsAb start was 67 years (interquartile range [IQR] 58-76). Most were male (62.2%), and the most common histology was diffuse large B-cell lymphoma (n=155 [74.2%]). Of pts with molecular testing (n=168), 34 (20.2%) had double/triple hit lymphoma. Most (78.9%) had Ann Arbor stage III-IV disease and 91% had an ECOG performance status of ≤1. Median number of lines of treatment before BsAb was 3 (range 1-12). Of pts with known response assessment following front-line therapy, 54 (32.1%) had primary refractory disease, defined as failure to achieve PR or CR to front-line therapy. Most pts (n=126 [60.3%]) received prior chimeric antigen receptor (CAR) T-cell therapy and 21 (10.0%) received prior autologous hematopoietic progenitor cell transplant. CD20 expression was assessed in 106 biopsies (50.7%) prior to BsAb and was positive in 90 (84.9%). A total of 172 pts were response-evaluable. The best ORR was 50.6%, with CR in 41 (23.8%), PR in 46 (26.7%), stable disease in 10 (5.8%), and progressive disease in 75 (43.6%). The ORR and CR rates were 49% and 23% for Epco, and 53% and 25% for Glofit, respectively. With a median follow-up of 5 months, the median PFS was 2.7 months (95% CI 2.0, 3.9) and median OS was 7.2 months (95% CI 6.1, not reached [NR]). The estimated PFS and OS at six months were 35% (95% CI 29%-43%) and 59% (95% CI 52%-67%), respectively. For pts who relapsed after CAR T-cell therapy, the median PFS and OS were 2.5 (95% CI 1.8, 4.7) and 7.8 (95% CI 6.2, NR) months, respectively. Pts without detectable CD20 expression via immunohistochemistry or flow cytometry prior to BsAb therapy had significantly inferior outcomes (PFS 1.1 vs 3.4 months, P < 0.001 and OS 1.3 vs 13 months, P < 0.001) compared to pts with detectable CD20. CRS of any grade occurred in 82 pts (39.2%), corresponding to 51.1% and 28.6% of pts treated with Epco and Glofit, respectively. Grade ≥3 CRS occurred in 9 (4.3%), all of whom received Epco. CRS was treated with tocilizumab in 43 pts (53.1%). ICANS occurred in 24 (11.5%) pts; any grade ICANS occurred in 13.7% and 7.1% of pts treated with Epco and Glofit, respectively. Grade ≥3 ICANS occurred in 6 pts (2.9%), 5 of which received Epco (3.6%). Of those experiencing ICANS, 66.0% were treated with corticosteroids. Two pts had deaths attributed to ICANS and one to CRS. A total of 122 (58.4%) pts discontinued therapy after a median of 3 cycles (range 0-48), 91 (74.6%) due to disease progression and 31 (25.4%) due to adverse events (15 due to infection, 3 due to ICANS, 2 due to CRS, and 11 for other reasons). Conclusions: In this heavily pretreated group with adverse disease features and high rate of CAR T exposure, the response rates, PFS, and OS following BsAb therapy were lower compared to pivotal trials. Poor outcomes were observed for those without detectable CD20. Rates of ICANS and grade ≥3 CRS were higher than reported in pivotal trials, as was the rate of discontinuation of therapy due to adverse events. Future efforts to improve outcomes may include intensified dose escalation protocols to more rapidly achieve disease control, combination therapies, and characterization of clinicopathologic factors that predict response to BsAb to identify subgroups of pts who can derive maximal benefit from these agents.

Abstract Unirradiated patients with relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma (NHL) who undergo anti-CD19 chimeric antigen receptor T-cell therapy (CART) have a predominant localized pattern of relapse, the significance of which is heightened in individuals with limited/localized disease before CART. This study reports on the outcomes of patients with R/R NHL and limited (<5 involved sites) disease bridged with or without radiotherapy. A multicenter retrospective review of 150 patients with R/R NHL who received CART with <5 disease sites before leukapheresis was performed. Bridging treatment, if any, was administered between leukapheresis and CART infusion. Study end points included relapse-free survival (RFS), event-free survival (EFS), and overall survival. Before CART infusion, 48 patients (32%) received bridging radiotherapy (BRT), and 102 (68%) did not. The median follow-up was 21 months. After CART infusion, BRT patients had higher objective response (92% vs 78%; P = .046) and sustained complete response rates (54% vs 33%; P = .015). Local relapse in sites present before CART was lower in the BRT group (21% vs 46%; P = .003). BRT patients had improved 2-year RFS (53% vs 44%; P = .023) and 2-year EFS (37% vs 34%; P = .039) compared with patients who did not receive BRT. The impact of BRT was most prominent in patients who had ≤2 pre-CART involved disease sites, with 2-year RFS of 62% in patients who received BRT compared with 42% in those who did not (P = .002). BRT before CART for patients with limited (<5 involved disease sites) R/R NHL improves response rate, local control, RFS, and EFS without causing significant toxicities.