Yi, Cecilia Arana

SummaryGermline variants in DDX41 (DDX41MT‐germline predisposition syndrome [GPS]) are associated with predisposition to haematological malignancies (HM), including lymphoid and myeloid neoplasms (MN). We retrospectively analysed the clinical and molecular features of 195 patients diagnosed and treated at Mayo Clinic with DDX41MT‐GPS. Patients with germline DDX41 pathogenic variants (42.3%) and variants of unknown significance (VUS, 57.6%) were included. The median age was 68.6 years (16.2–93.4). Ninety‐two per cent were Caucasian, 64.1% were male and 30.8% had a family history of HM. There were 92 distinct germline variants among our cohort, and the most common was p.Met1? (15.9%), followed by p.Asp140Glyfs*2 (9.2%). Clinical diagnoses included asymptomatic carriers (10.2%), clonal cytopenia of undetermined significance (CCUS, 6.1%), myeloproliferative neoplasms (6.7%), myelodysplastic syndrome (40.5%), acute myeloid leukaemia (20.5%), lymphoid neoplasms (9.2%), plasma cell dyscrasias (6.1%) and solid tumours (22.5%). Patients with MN were older (median age 70 vs. 63.5 years) and more likely to be male (M:F ratio 2.3 vs. 1.0) and most patients (78.8%) with MN had a normal karyotype. The most common somatic variants involved DDX41 (34.4%), followed by TET2 (11.2%), DNMT3A (9.6%) and ASXL1 (9.2%). In summary, we have comprehensively described the spectrum of clinical phenotypes within the Mayo Clinic DDX41MT‐GPS cohort.

Abstract Background: Age-related clonal hematopoiesis (ARCH) is a precursor state to blood cancers and is associated with epigenetic age acceleration (EpiAgeAccel). While ARCH is associated with increased all-cause mortality and cardiovascular disease, not much is known about these risks with therapy-related clonal hematopoiesis (t-CH) – CH occurring in the context of prior cytotoxic chemotherapy/radiation exposure. Methods: Patients were prospectively recruited for CH and EpiAge assessment from Mayo Clinic between 2022 and 2024. CH status was determined using error corrected sequencing on peripheral blood (PB) DNA (sensitivity 0.5% VAF). Patients with CH were classified as t-CH if they had received chemotherapy or radiation prior to CH detection. All other CH cases were classifed as ARCH. For EpiAge analysis, PB DNA was analyzed using the Illumina MethylationEPIC array. The resulting beta values were used to obtain epigentic age estimates using Horvath’s clock, Hannum’s Clock, PhenoAge, DunedinPACE, and estimated telomere lengths (DNAmTL). Results: 106 (62%) of 170 patients assessed were found to have CH. CH patients were classified into ARCH-63 (59%) and t-CH-43 (41%). While the median chronological age (69 vs 67 years) was similar between ARCH and t-CH, t-CH patients had lower Hgb [10.9g/dL vs. 13g/dL (p=0.0001)], lower platelet [146x109/L vs. 192x109/L (p=0.0132)] and lower WBC [4.4x109/L vs. 5.2x109/L (p=0.0345)]. The 3 most common ARCH mutations were TET2 (20%), DNMT3A (19%), and ASXL1 (14%), while PPM1D (27%), TET2 (18%), and DNMT3A (14%) were most frequent in t-CH. There was no significant difference in median EpiAge via Horvath (68 vs 67.5years p=0.2826), Hannum (65 vs 66 years p=0.9333), or PhenoAge (55 vs 56 years p=0.618) between ARCH and t-CH. However, DunedinPACE of aging was higher in t-CH (1.27 vs 1.18 bioyear/chronoyear p=0.0148) and median DNAmTL was shorter in t-CH (6.35 vs 6.49kb p=0.0247), compared to ARCH (Note patients with telomere biology disorders were excluded). Multivariable regression analysis adjusting for chronologic age, smoking status, and male sex showed that both ARCH and t-CH had EpiAgeAccel via Horvath(5.8years p=0.0001, 3.4 years p=0.051), Hannum(5years p=0.001, 4.5 years p=0.007), and PhenoAge (6.7years p=0.002, 7.6 years p=0.002) clocks. t-CH more than doubled DunedinPACE (0.2 bioyear/chronoyear, p<0.001) of aging compared to ARCH (0.08 bioyear/chronoyear, p=0.026). t-CH also demonstrated a significant decrease in DNAmTL (0.34kb, p<0.001) in comparison to ARCH (0.17kb, p=0.015). With a median follow-up of 20 months, t-CH was associated with worse overall survival in comparison to ARCH, and non-CH patients (p=0.013, 93% vs. 90% alive at 10 months, 87 vs. 72% alive at 20 months). Conclusion: Our prospective CH cohort study validates the association between CH and EpiAgeAccel using several different methylation clocks and for the first time highlights an increased pace of aging and shorter DNAmTL in the context of inferior survival outcomes in t-CH. Citation Format: Marissa Li, Jenna Fernandez, Kristina Kirschner, Tamir Chandra, Kristen McCullough, Sarah Aug, Terra Lasho, Christy Finke, James Foran, Cecilia Arana Yi, Yael Kusne, Talha Badar, Abhishek Mangaonkar, Naseema Gangat, Rachel Simon, Alejandro Ferrer, Mrinal Patnaik. A prospective cohort study of biological aging and epigenetic age acceleration in 106 patients with age and therapy-related clonal hematopoiesis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: DNA Methylation, Clonal Hematopoiesis, and Cancer; 2025 Feb 1-4; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2025;85(3 Suppl):Abstract nr A015.

ABSTRACT Patients with newly diagnosed acute myeloid leukemia (ND‐AML) derive variable survival benefit from venetoclax + hypomethylating agent (Ven‐HMA) therapy. The primary objective in the current study was to develop genetic risk models that are predictive of survival and are applicable at the time of diagnosis and after establishing treatment response. Among 400 ND‐AML patients treated with Ven‐HMA at the Mayo Clinic, 247 (62%) achieved complete remission with (CR) or without (CRi) count recovery. Multivariable analysis–derived hazard ratios (HR), including 1.8 for European LeukemiaNet (ELN) adverse karyotype, 4.7 for KMT2Ar , 1.7 for TP53 MUT , 2.6 for KRAS MUT , and 2.1 for IDH2 WT were applied to develop an HR‐weighted risk model: low, intermediate, and high; respective median survival censored for allogeneic stem cell transplant (ASCT) (3‐year survival) were “not reached” (67%), 19.1 (33%), and 7.1 months (0%). In patients achieving CR/CRi, adverse karyotype, KMT2Ar , KRAS MUT , IDH2 WT predicted inferior survival, allowing for a complementary response‐stratified risk model. The model was externally validated and was shown to be superior to the ELN 2024 risk model (AIC 179 vs. 195 and AUC 0.77 vs. 0.69). Survival was inferior with failure to achieve CR/CRi or not receiving ASCT; 3‐year survival for high‐risk with or without ASCT was 42% versus 0% ( p < 0.01); intermediate 72% versus 43% ( p = 0.06); and low‐risk 88% versus 78% ( p = 0.53). The Mayo genetic risk models offer pre‐treatment and response‐based prognostic tools for ND‐AML treated with Ven‐HMA. The current study underscores the prognostically indispensable role of achieving CR/CRi and ASCT.

Background: Systemic mastocytosis (SM) is a rare disease characterized by neoplastic mast cell (MC) infiltration of extracutaneous tissues. Nonadvanced SM (NonAdvSM) is associated with debilitating symptoms which may significantly reduce health-related quality of life (HRQoL). In up to 95% of patients (pts), SM is driven by the somatic KIT c.2447 A&gt;T (p.D816V) missense mutation. Bezuclastinib (bezu; CGT9486) is an oral, potent, small molecule, selective type 1 tyrosine kinase inhibitor (TKI) with activity against KIT D816V. Results from Part 1 of the 3-part Summit trial demonstrated that bezu is well-tolerated and is associated with encouraging clinical activity, including both reduced MC burden and improvement in symptoms over a 12-week (wk) period vs placebo (PBO). Based on safety, PK, biomarker, and efficacy results, a dose of 100mg QD bezu (optimized formulation) was selected for Summit Part 2. Trial Design and Methods: Summit (NCT05186753) is a multi-center, Phase 2, double-blind, PBO-controlled RCT of bezu in pts with NonAdvSM who have inadequate control of symptoms despite treatment with best supportive care (BSC). A novel pt-reported outcome measure, the Mastocytosis Symptom Severity Daily Diary (MS2D2), was designed to assess disease-specific symptom severity in NonAdvSM pts. Eleven symptoms are included in the MS2D2 Total Symptom Score (TSS). Summit Part 1a randomized pts 1:1:1 to PBO, 100mg, or 200mg, original formulation while Part 1b randomized 1:1:1 to PBO, 100mg, or 150mg, optimized formulation. Pts completing Part 1 of the Summit trial were allowed to receive bezu in the open-label extension (OLE) Part 3 of the trial. Results: As Part 2 will evaluate safety and efficacy of 100 mg bezu at 24 wks, this abstract reports on pts treated with both bezu formulations at 100mg in Parts 1a or 1b, which had similar PK exposures. The presentation will focus on 24-wk outcomes in pts receiving the selected 100 mg bezu dose and participating in the OLE. In Summit Part 1, 19 pts received PBO and 18 received 100 mg bezu for 12 wks. At baseline (BL), the symptoms identified as most severe were within the skin and fatigue domains. At BL, pts were managing their symptoms of NonAdvSM with 2 (43%), 3 (24%), or ≥4 (32%) BSC medications. At the 12-wk assessment in Part 1 (datacut 18Dec2023), the safety and tolerability profile was encouraging, with the majority of TEAEs low grade and reversible without dose modification. The most common TEAEs (&gt;10% in 100 mg bezu) included hair color changes, nausea, diarrhea, peripheral edema, GERD, taste disorder, and neutropenia. There were no reported bleeding or cognitive impairment events. Of 37 pts randomized to PBO or 100 mg QD bezu, 36 (97%) received bezu in the OLE; one pt randomized to the 100 mg original formulation dose reduced and subsequently discontinued due to TEAE of ALT increase. All 19 PBO pts (100%) crossed over to receive bezu in the OLE; of these, 9 were randomized to the 100mg QD bezu dose. Reduction in MC burden was robust among those treated with 100mg bezu - 94.4%, 100%, and 92.3% of pts had at least a 50% reduction in basal serum tryptase, KIT p.D816V variant allele frequency, and bone marrow MCs, respectively. Pts treated with 100 mg bezu had reduction in MS2D2 TSS by 49.1% vs 21.1% with PBO. On a 0-10 scale, the most severe MS2D2 symptom mean change from BL was -3.03 from a BL mean of 7.6 with bezu vs -1.04 from a BL mean of 7.7 with PBO. Individual symptoms of the MS2D2 TSS, as well as others not in the TSS including diarrhea and brain fog, improved more with bezu than with PBO; mean change from BL ranged from -1.66 to -2.69 with bezu vs. a range of -0.52 to -1.58 with PBO. LS mean change from BL in quality of life (Mastocytosis (MC)-QoL, a disease-specific measure) was -22.05 in pts treated with 100mg bezu versus -10.71 in pts treated with PBO. Objective measurements of skin lesions, including centrally adjudicated longitudinal assessments of skin photography, also significantly reduced on bezu. Conclusions: In Part 1 (12 wk assessment), treatment with 100mg bezu resulted in favorable safety and tolerability, significant and deep reductions across all markers of MC burden, and clinically meaningful reduction in all individual MS2D2 TSS symptoms and across domains. The presentation will report on durability and safety/tolerability data beyond 12 wks for those pts randomized to 100 mg in Part 1 and pts who crossed over from PBO in Part 1 to 100mg in Part 3. Summit Part 2 is actively enrolling.

Background: TP53-mutated (TP53mut) myeloid neoplasms (MN) have particularly poor survival. Discrepancies in defining TP53mut MN have impact on diagnostic work up, therapeutic decisions, and clinical trial enrolment. Methods: MN cases harboring TP53mut (variant allele frequency, VAF ≥2%) were classified based on bone marrow (BM) and peripheral blood (PB) blast % using the 4th revision of the WHO classification (WHO-4R). Biallelic loss was defined as (i) ≥2 mutations each with VAF ≥2%; (ii) single TP53mut VAF ≥2% plus 17p loss detected on karyotype, FISH, or SNP; or (iii) single TP53mut VAF ≥50%, whereas monoallelic loss was defined as single TP53mut VAF &lt;50% without 17p loss. Primary endpoint was overall survival (OS) from diagnosis. Conditional Inference Trees (CIT) analysis was used to determine the true effect of a predictor. Results: We identified 580 cases including WHO-4R defined acute myeloid leukemia (AML, BM/PB blasts ≥20%, n=219, 37.8%), myelodysplastic syndrome (MDS) with excess blasts-2 (EB-2, BM 10-19% or PB 5%-19%, n=92, 15.9%), MDS with excess blasts-1 (EB-1, BM 5-9% or PB 2-4%, n=75, 12.9%), and the remaining were MDS with low blasts (-LB, BM &lt;5% and PB ≤1%, n=194, 33.4%). Of the 578 cases evaluable for allelic status, 437 (75.6%) and 141 (24.4%) had biallelic and monoallelic TP53 loss, respectively. Higher frequency of biallelic loss was observed with increasing blasts. 63.2%, 73.3%, 78% and 86.3% of cases with MDS-LB, MDS-EB1, MDS-EB2, and AML had bi-allelic TP53 loss (P&lt;0.0001). In a multivariable analysis, WHO-4R categories, VAF ≥10%, and biallelic loss were independent predictors of poor survival. CIT analysis further stratified the cohort into 4 groups with distinct survival: (1) MDS-LB (n=194, 33.4%); (2) MDS-EB1/EB2 and AML with VAF &lt;10% (n=38, 6.6%); (3) MDS-EB1/EB2 with VAF ≥10% (n=149, 25.7%); and (4) AML with VAF ≥10% (n=199, 34.3%). MDS-LB cases could be further stratified based on allelic status and complex karyotype (CK): OS was poor for cases with biallelic TP53 loss and monoallelic TP53mut with CK compared to monoallelic TP53mut without CK, who had the most favorable survival (12.7 vs. 13 vs. 34.8 months, P&lt;0.0001).MDS-EB1/EB2/AML with VAF&lt;10% could also be stratified by CK: MDS-EB1/EB2/AML with VAF&lt;10% cases without CK had the favorable survival compared to their counterparts with CK and MDS-EB1/EB2 with VAF ≥10% cases (26.2 vs. 5.6 vs. 6.3 months, P=0.003).MDS-EB1/EB2 with VAF ≥10% was a homogenous subgroup: Biological characteristics including the proportion of cases with biallelic TP53 loss, CK (P&gt;0.9), monosomal karyotype (MK, P&gt;0.9), del 5q (P=0.6), del 7q (P=0.4), and del 17p (P=0.2) were comparable between MDS-EB1 and -EB2 with VAF ≥10%. Importantly, median OS of MDS-EB1 and EB2 with VAF ≥10% was comparable (9.6 vs. 7.2 months, P=0.12). OS in this group was comparable regardless of the blast %, allelic status, or presence of CK.AML with VAF ≥10% had extremely poor survival: Median OS was 3.9 months. Survival of AML was equally poor irrespective of the mono- or biallelic (3.6 vs. 3.9, P=0.89) and non-CK vs. CK (1.8 vs. 3.9 months, P=0.09). Combined, our model would acknowledge poor survival of 514 (89.1%) cases. In contrast, retrospective application of the 5th edition of the WHO classification (WHO-5) and International Consensus Classification (ICC) would classify only 211 (36.4%) and 468 (80.7%) cases as biallelic/multi-hit TP53mut MN, respectively. Finally, the Harrell's c-index of the proposed model, WHO-5, and ICC was 0.66, 0.571, and 0.617, respectively. Conclusion: We provide evidence for subsequent refinements in classifying MN harboring TP53mut. Our salient findings include: (i) acknowledgement of CK as ‘biallelic equivalent’ in MDS-LB; as well as EB1/EB2/AML with VAF 2 to &lt;10% cases; and (ii) demonstration of poor survival of MDS-EB1 and -EB2 with VAF ≥10% regardless of the allelic status. In conclusion, our proposed model acknowledged poor survival of a higher proportion of cases as TP53mut MN compared to the current models with a higher c- index.

Background Venetoclax + hypomethylating agent (Ven-HMA) therapy results in favorable response rates (CR/CRi 66%) and overall survival (OS; median 14.7 months) in unfit patients with newly-diagnosed acute myeloid leukemia (ND-AML; N Engl J Med 2020;383). However, there is substantial heterogeneity in individual patient outcomes based on response to treatment. The objective of the current study was to develop a genetic risk model to predict survival outcome in treatment responders and non-responders, analyzed separately, and also account for allogeneic stem cell transplant (ASCT). Methods Treatment-naïve AML patients receiving Ven-HMA, outside of a clinical trial, at the Mayo Clinic, USA (MN, AZ, FL) were retrospectively recruited. Molecular studies (48-gene panel) were performed by next-generation sequencing. Response was assessed according to the 2022 European LeukemiaNet (ELN) criteria (Blood 2022;140). Standard statistical analyses were performed using JMP Pro (Version 17.0.0). Results 400 ND-AML patients (median age 73 years, 64% male, 60% de novo) received Ven-HMA. ELN cytogenetic risk included favorable 2%, intermediate 60%, or adverse 38%. Mutations involved TP53 in 26%, TET2 19%, RUNX1 19%, SRSF2 18%, ASXL1 18%, DNMT3A 15%, K/NRAS 13%, NPM1 12%, IDH2 12%, FLT3-ITD 10%, IDH1 7% and DDX41 in 4% of informative cases. 153 (38%) patients achieved CR, 94 (24%) CR with incomplete count recovery (CRi), resulting in CR/CRi in 247 (62%) patients. CR/CRi rates were higher with NPM1 (86% vs 59%), IDH2 (77% vs 60%), and DDX41 mutations (93% vs 61%) and lower with TP53 (45% vs 67%), FLT3-ITD (41% vs 64%), RUNX1 (49% vs 65%) mutations and adverse karyotype (48% vs 71%), with all retaining significance in multivariable analysis. CR/CRi rate was highest (87%) in 75 patients with one or more favorable mutations (NPM1, IDH2, DDX41) and no unfavorable mutation (TP53, FLT3-ITD, RUNX1). CR/CRi rate was lowest in 171 patients with at least one unfavorable mutation and no favorable mutation (44%; p&lt;0.01). After a median follow up of 10.5 months (0.5-66), 105 relapses (43% of patients in CR/CRi), 248 (62%) deaths and 65 (16%) ASCT were documented. Univariate analysis for transplant-censored OS disclosed superior survival in patients achieving CR/CRi (median 21 vs 3.6 months; HR 5.4, 95% CI 4.1-7.1). Among patients achieving CR/CRi, IDH2 mutation was associated with superior (median not reached vs 20.5 months) and male gender (median 17.6 vs 29.2 months), TP53 mutations (median 11.9 vs 24.3 months) and adverse karyotype (median 12.6 vs 29.4 months) with inferior survival; multivariable analysis resulted in HRs (95% CI) of 2.1 (1.3-3.4) for male gender, 2.1 (1.2-3.8) for adverse karyotype, and 2.5 (1.1-5.7) for absence of IDH2 mutations. Male gender did not show an association with karyotype, or TP53 mutations (p&gt;0.1). Accordingly, an HR-weighted genetic risk model was generated with assignment of one point each to male gender, adverse karyotype, and absence of IDH2 mutation: high risk = 3 risk factors (n=38; median 9.6 months; 3-year survival 0%); intermediate risk = 2 risk factors (n=129; median 22 months; 3-year survival 38%); and low-risk = ≤1 risk factor (n=78; median not reached; 3-year survival 69%; p&lt;0.01). In patients bridged to ASCT (n=60), post-transplant survival was inferior in the presence of ≥ 2 risk factors (n=42; median 46 months) vs. ≤1 risk factor (n=18; median not reached; p=0.1). In patients not achieving CR/CRi, risk factors for OS included male gender (median 3.4 vs 6.1 months), adverse karyotype (median 3.3 vs 4.5 months) and TP53 mutation (median 3.1 vs 4.5 months) while those with IDH2 mutations lived longer (median 8.4 vs 3.4 months). In multivariable analysis, HRs (95% CI) were 1.9 (1.3-2.9) for male gender, 2.0 (1.4-2.9) for adverse karyotype, and 2.1 (1.1-4.3) for absence of IDH2 mutations. OS was shortest for non-responders harboring 3 risk factors (n=45; median 3 months; 1-year survival 0%) and longer for those harboring two (n=80; median 6 months, 1-year OS 15%) or ≤ 1 risk factor (n=25; median 14 months; 1-year OS 56%; p&lt;0.01). Conclusion The current study describes a molecular profile for predicting response to Ven-HMA in ND-AML and also introduces a novel approach to survival prediction that considers treatment response as the starting point. In both responders and non-responders, male gender and adverse karyotype were identified as unfavorable and IDH2 mutation favorable risk factor for OS.

Background: Philadelphia (Ph)-like acute lymphoblastic leukemia (ALL) is a heterogenous subtype of B-ALL defined by the presence of gene expression profiling similar to Ph+ ALL in the absence of a BCR::ABL1 fusion. Ph-like ALL has lower response rates to standard frontline therapies and carries a poorer prognosis when compared to other B-ALL subtypes. However, the role in which specific patient characteristics may impact responses is not well described. Our aim for this retrospective study was to evaluate the characteristics and outcomes of a real-world cohort of patients (pts) with Ph-like ALL across multiple institutions, including describing key patient characteristics, treatments, and factors that may contribute to minimal residual disease (MRD) status and treatment response. Methods: We conducted a retrospective review of adult pts with Ph-like ALL diagnosed and treated at the University of New Mexico, Mayo Clinic Phoenix, University of Chicago, and University of Michigan between 1/1/18 - 2/1/2024. Pts were eligible if they carried a diagnosis of B-ALL, and were determined to have Ph-like ALL according to each institutional diagnostic algorithm. Descriptive statistics, ANOVA, and Fisher's exact test were employed to summarize various clinical characteristics and their associations. Cox regression analysis was utilized to estimate the median survival time and assess the relationship between clinical characteristics and survival outcomes, including overall survival and progression-free survival. All statistical analyses were conducted using the R statistical software. Results: 67 pts were identified with a median age of 34.2 (IQR 28.5) and 35.8% were female. Twenty-eight pts identified as Hispanic or Latino (H/L) (43.1%), 25 (38.5%) identified as non-Hispanic White/Caucasian (NHW), 10 (15.4%) as American Indian/Alaska Native (AI/AN), and 2 (3.1%) as Asian/Pacific Islander. Thirteen pts (19.4%) had central nervous system (CNS) involvement at diagnosis, 22.4% of pts had extramedullary disease, and, in those who had NGS or cytogenomic microarray testing (n=49), 51% had an identified mutation/deletion in IKZF1. Initial treatment varied widely with pts receiving most commonly: Children's Oncology Group (COG) protocols (22.4%), CALGB 10403 (22.4%), HyperCVAD (11.9%), and CALGB 8811 (10.4%). Fifty-eight percent achieved a CR/CRi and 21% were refractory to initial therapy. Thirteen percent of pts received a Jak inhibitor and 6% of pts were treated with a TKI. Thirty pts (50.8%) underwent allogeneic stem cell transplant, with 8 of those pts (26.7%) experiencing a relapse post-transplant. Nine pts (13.4%) underwent treatment with CAR-T therapy with few pts experiencing grade 2 or higher cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS). Pts with CNS disease at diagnosis were less likely to achieve a CR/CRi compared to those without CNS disease at diagnosis (33.3% vs 64.0%; p=0.12). Pts identifying as AI/AN were more likely to be refractory to their first treatment compared to other racial/ethnic groups (75%, p=0.002). Forty two percent of pts never achieved MRD negativity (&lt; 0.01% by flow cytometry) during treatment; pts identifying as H/L and AI/AN had a higher rate of MRD positivity after induction compared to NHW pts (56% and 70% vs. 25%; p=0.02). In pts with IKZF1 mutation, 57.1% did not achieve MRD negativity compared to 21.7% in pts without a mutation (p=0.029). The median overall survival (OS) was 66.3 months (mos) and the median progression-free survival (PFS) was 15.7 mos. Pts who did not achieve MRD negativity after initial treatment had shorter OS compared to those who did achieve MRD negativity, 33.9 mos vs 66.3 mos (p=0.086). Progression-free survival (PFS) was significantly shorter for patients who did not achieve MRD negativity after initial treatment compared to those who did, 3.9 mos vs 43.9 mos (p=0.001). PFS was shorter in pts who identify as AI/AN compared to H/L and NHW pts (2 mos vs 35.7 mos and 35.7 mos; p=0.046). Conclusion: Pts with Ph-like ALL experience poor response rates to therapies used to treat B-ALL, highlighting the urgent need for novel therapies and treatment strategies. We identified race/ethnicity and CNS disease at diagnosis as risk factors for poor treatment response. In addition, race/ethnicity and the presence of an IKZF1 mutation was associated with worse rates of MRD negativity during treatment.

Background Venetoclax + hypomethylating agent (Ven-HMA) therapy has demonstrated improved outcomes in elderly/unfit patients with newly-diagnosed acute myeloid leukemia (ND-AML) (N Engl J Med 2020;383). However, ~50% of patients who respond to Ven-HMA, eventually relapse (Am J Hematol 2024;99). In the current study we examined the prognostic contribution of gene mutations, karyotype, measurable residual disease (MRD) status and clinical risk factors for relapse in patients with ND-AML treated with Ven-HMA therapy. Methods Our study population of ND-AML was retrospectively recruited from Mayo Clinic (MN, AZ, FL), after institutional review board approval and based on documentation of complete remission with/without count recovery (CR/CRi) following Ven-HMA therapy. Relapse-free survival was determined from the time of remission to relapse or last follow-up. Survival analysis was censored for transplant. The 2022 European LeukemiaNet (ELN) criteria was used to assign cytogenetic risk and classify treatment response (Blood 2022;140). Standard statistical analyses were performed using JMP Pro (Version 17.0.0). Results 247 ND-AML patients treated with Ven-HMA (median age 73 years, 62% male, 64% de novo) who achieved CR (n=153), or CRi (n=94) were included. MRD by multiparameter flow cytometry (sensitivity 0.01%) performed at the time of CR/CRi, was negative in 117 (70%) of 166 informative cases. ELN cytogenetic risk categories at diagnosis included favorable 2%, intermediate 69%, or adverse 29%. Mutations involved TET2 21%, SRSF2 21%, TP53 19%, ASXL1 18%, DNMT3A 18%, NPM1 17%, IDH2 15%, RUNX1 15%, K/NRAS 12%, IDH1 8%, FLT3-ITD 7%, and DDX41 in 6% of informative cases. Relapse was documented in a total of 99 (40%) patients who achieved CR (39%) or CRi (41%) after a median remission duration of 6 months (1-31). Patients that relapsed within the first-year vs those that did not, were more likely to be males (75% vs 55%), MRD positive (44% vs 24%), and harbor TP53 mutations (23% vs 16%). Univariate analysis for RFS identified male gender (12 vs 29 months; p=0.02), secondary AML (10 vs 21 months; p&lt;0.01), adverse karyotype (9 vs 22 months; p&lt;0.01), TP53 mutations (6 vs 18 months, p&lt;0.01) and MRD positive remission (13 months vs not reached; p&lt;0.01) as risk factors for relapse; on the other hand, IDH2 mutations (not reached vs 15 months; p&lt;0.01) were associated with a lower risk of relapse. Multivariable analysis confirmed male gender (HR 2.2), TP53 mutations (HR 3.0) and MRD positive remission (HR 1.7) as unfavorable predictors of relapse. Subsequently, in a three-tiered relapse prediction model, RFS was significantly inferior in the presence of three risk factors (male gender, TP53 mutations, MRD positive remission) (n=10, median 4 months), vs two (n=34, median 10 months) vs ≤ 1 risk factor (n=122, median 31 months) (p&lt;0.01); 1-year cumulative incidence of relapse was 100%, 56%, and 26% in the presence of three, two and ≤ 1 risk factors, respectively. 50 of 99 (65%) patients received salvage therapy which included cladribine-cytarabine-Ven (n=19), intensive induction chemotherapy (n=9), FLT3 inhibitors (n=5), Ven-HMA-FLT3 inhibitor (n=1), IDH1/2 inhibitors (n=5), glasdegib-cytarabine (n=4), gemtuzumab (n=3), lenalidomide (n=1), or investigational therapies (n=3); in addition, Ven-HMA was resumed in 14 patients in whom treatment had been discontinued for a median of 5 months (2-12). Overall, 20 (31%) of patients achieved second CR/CRi and response rates were similar with intensive vs less intensive therapy (CR/CRi; 44% vs 29%; p=0.37). Median follow up after relapse was 3.4 months (1-66), during which 73 (74%) deaths, and 4 (5%) ASCT were recorded. Median transplant-censored survival was 4.2 months (1-year; 22%), and inferior in patients with adverse karyotype (median 4.6 vs 3.4 months; p=0.02), and TP53 mutations (3.6 vs 4.4; p=0.11); on the other hand, male gender (3.5 vs 6.8 months; p=0.51), MRD positive remission (4.6 vs 4.2; p=0.56), and IDH2 mutations (6.7 vs 4.2; p=0.28), did not influence post-relapse survival. Conclusions The current study identifies male gender, TP53 mutations, and MRD status as powerful predictors of relapse and proposes a relapse prediction model for ND-AML patients receiving Ven-HMA therapy. Furthermore, relapse following Ven-HMA was associated with uniformly poor outcomes, regardless of salvage treatment strategy.

Introduction: DDX41, DEAD-box RNA helicase 41 gene located on chromosome 5q25.3, is one of the most mutated genes in patients with germline predisposition to myeloid neoplasms. Germline and somatic mutations often have different locations and patterns of mutation, with some hot-spots displaying diversity based on ethnicity. We aimed to explore clinical outcomes in patients with various DDX41 hot-spots. Methods: A retrospective study of patients at Mayo Clinic with DDX41 mutation identified through Next Generation Sequencing (NGS) between 2016 and 2024. Patients classified as germline DDX41 variants or somatic variants based on confirmed germline testing results. Data regarding mutations recorded at time of patients' first in-house NGS. We completed unadjusted comparisons using continuous or categorical variables, and survival rates assessed using Kaplan-Meier method and cox regression analysis. Median overall survival calculated from time of NGS to last follow-up or death using BlueSky Statistics V.10.3.4 Results: Clinical Characteristics: Eighty-two patients analyzed, predominantly male (69.5%), with median age of diagnosis of 68 years (IQR 62-75). Most common diagnosis was MDS (50%), followed by AML (22%) and myeloproliferative neoplasm (MPN) (7.3%). Fourteen percent were DDX41 mutation carriers, 4.9% clonal cytopenia of undetermined significance (CCUS), and 1.2% chronic neutrophilic leukemia (CNL). MDS-IB2 was the prevalent MDS subtype (56.1%), and 83.3% of AML patients were intermediate risk. Cytogenetics normal in 73.8% of patients, with del20 being the most common abnormality (7.5%). Twenty-five (30.5%) of patients underwent allogeneic hematopoietic cell transplantation (alloHCT). Forty-nine patients (59.8%) had pathogenic DDX41 mutation only, 15 (18.3%) had only VUS, and 18 (22.0%) had both. Molecular Characteristic s: Mutation hot-spots included 12.2% with p.Arg525His only, 28% p.M1I only, 9.8% p.Asp140GlyFs*2 only, 9.8% p.Arg525 with co-mutation other than p.M1I/p.Asp140. Two patients (2.4%) had p.M1I co-mutation with non-p.Arg525 and p.Asp140, while 1 patient (1.2%) had p.M1I and p.Arg525, and 1 patient (1.2%) had p.Asp140 and p.Arg525. Lastly, 33 patients (40.2%) had mutations in hot-spots other than specified in this study. Median hemoglobin (Hg) was lowest in patients with p.Arg525 hotspot mutation (9.9 g/dl), compared to median Hg of 11.2 g/dl in group with p.M1I and 10.4 g/dl in p.Asp140 only group (p=0.87). The most common cytogenetics in patients with only p.Arg525 and only p.M1I hot-spot mutation was normal cytogenetics (70% and 90.9%, p=0.5). In the 16 patients with proven germline DDX41 mutation, 7 (43.8%) had mutations in only p.M1I. Lastly, median (m) VAF was significantly lower in the group with only p.Arg525 hot-spot mutation (9.5%, IQR 5.5-13.8), compared to mVAF of 48% in patients with only p.M1I (IQR 48.0-49.5, p&lt;0.001). Co-mutations: The most frequent co-mutation was DNMT3A (11.0%), followed by JAK2 (9.8%).Mean number of co-mutations in p.Arg525 only was 0.6, 0.3 in p.M1I only, and 0.5 in p.Asp140 only (p=0.8). Most common co-mutation in p.M1I was ASXL1, with 13.0% of patients with p.M1I only having ASXL1 co-mutation (p=0.062). The most common co-mutation in p.Asp140 was DNMT3A (p=0.7). Survival: Median overall survival (mOS) was 21.5 months (IQR 12.4-38.6). mOS for p.Arg525 only group was 31.3, compared to 41.2 months in p.M1I only (p=0.197). At 12- and 24-months, survival rate was 88.9% and 59.3% in the p.Arg525 only group, compared to p.M1I group with 100% survival rate at 12 months and 89.5% at 24 months. p.Asp140 had 87.5% survival rate at both 12 months and 24 months. Males in p.M1I group had lower survival rate at 24 months (81.8%), compared to 100% survival in females. p.M1I only group with alloHCT also had lower 24 month survival at 60% compared to 100% in group who did not undergo alloHCT. Conclusions: The p.M1I hot-spot was commonly seen in patients with germline DDX41 mutation, likely resulting in significantly higher VAF percentage. Co-mutations frequency differed by hot spot mutation while p.Arg525 as second mutation was seen mainly in cases other than p.M1I/pArg140Gly. Overall survival appears to be higher in p.M1I/pArg140Gly compared to p.Arg525His hot-spot mutation, though males with p.M1I and those who underwent alloHCT had lower survival. Findings suggest implications for clinical outcomes based on DDX41 mutation hot-spots.

Introduction Symptom burden in myeloproliferative neoplasms (MPN) is quantified using total symptom scores (TSS) calculated from the patient-reported scores for clinically meaningful symptoms. The impact of demographic, clinical, and laboratory features on these symptoms remains unclear and warrants further investigation. Methods Patients with polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis (MF) were identified from the retrospective chart review. TSS, scores of individual symptoms (fatigue, early satiety, abdominal discomfort, inactivity, concentration difficulties, fever, night sweats, itching, bone pain, weight loss), demographic characteristics (race, ethnicity, age, and gender), clinical features (time since diagnosis, depression status, obesity status), laboratory results and season at the time of visit when the first TSS assessment was performed were recorded. Multicollinearity and homoscedasticity were assessed using variance inflation factors and visual inspection of the data, respectively. A multivariable regression analysis was performed using a robust variance estimator. A p-value &lt;0.05 indicated a statistically significant association with the symptom scores. Results The chart review identified 557 (PV: 201; ET: 191; MF: 165) patients. The median age of patients with PV, ET, and MF was 65 (range: 27-93), 65 (20-96), and 69 (27-96) years, respectively. Most patients were white (PV: 92%; ET: 90%; MF: 93%) and non-Hispanic or Latino (PV: 93%; ET: 96%; MF: 92%). Most patients with PV and ET were female (PV: 51%; ET: 73%), while most patients with MF were male (55%). Among the included patients 22% (PV: 21%; ET: 27%; MF: 18%) had the diagnosis of depression at the time of the clinical visit. TSS was highest in MF (mean (SD): 18.1±14.6), followed by PV (15.7±14.5) and ET (15.1±14.0) patients. Fatigue was the most reported symptom by the patients (PV: 81%; ET: 82%; MF: 84%), whereas weight loss was the least reported symptom (PV: 4.5%; ET: 6.3%; MF: 16%). With regards to the TSS multivariable regression analysis showed that age (beta coefficient: 0.2; p=0.01), depression (7.2; 0.008), and low hemoglobin (1.2; 0.003) in PV, depression (11.7; 0.001) in ET, and depression (9.5; 0.001), splenomegaly (6.9; 0.01), and WBC count (0.16; 0.048) in MF patients were significantly associated with TSS. In terms of individual symptoms in PV, depression was associated with fatigue (beta coefficient: 1.31; p-value: 0.01) and concentration difficulties (1.7; &lt;0.001), high WBC count was associated with early satiety (0.09; 0.03), and non-white race was associated with fever (1.4; 0.007). In ET, depression was associated with fatigue (1.6; &lt;0.001), abdominal discomfort (1.4; &lt;0.001), inactivity (2.5; &lt;0.001), concentration difficulties (2.4; &lt;0.001) and night sweats (1.4; &lt;0.001), anemia was associated with fatigue (1.2; 0.03), fewer months since diagnosis was associated with inactivity (0.01; 0.02) and young age was associated with bone pain (0.02; 0.03). In MF, depression was associated with fatigue (1.8; 0.001), concentration difficulties (1.3; 0.01), fever (1.1; 0.02), and night sweats (2.2; 0.03), low hemoglobin was associated with fatigue (0.46; &lt;0,001) and early satiety (0.31; 0.003), high WBC count was associated with fatigue (0.03; 0.04) and early satiety (0.04; 0.02), low platelet count was associated with abdominal discomfort (0.002; 0.03), splenomegaly was associated with inactivity (2.27; 0.003) and female gender was associated with itching (0.57; 0.01). Conclusions This study demonstrates that depression in PV and ET and depression, low hemoglobin, and a high WBC count in MF contribute to multiple symptoms seen in these patients. Identifying demographic groups at risk of a higher symptom burden and addressing the comorbidities that drive symptoms, in addition to disease-directed therapy, is crucial to improving the quality of life in these patients.