Myelodysplastic Syndromes Subtypes Research Articles

Efficacy and safety analysis of venetoclax combined with hypomethylating agents for the treatment of higher-risk myelodysplastic syndromes in the real world

Objective: To investigate the efficacy and safety of combining venetoclax (VEN) with hypomethylated drugs (HMA) in the treatment of higher-risk (IPSS-R score >3.5) myelodysplastic syndromes (MDS) . Methods: From March 2021 to December 2022, forty-five MDS patients with intermediate and high risk were treated with VEN in combination with HMAs. Clinical data were collected and analyzed retrospectively, including gender, age, MDS subtype, IPSS-R score, treatment regimen, and efficacy, etc. Kaplan-Meier method and Cox regression model were used to analyze univariate and multivariate of survival prognosis. Results: ①Forty-five patients with MDS, including ninety-one percent were classified as high or very high risk. According to the 2023 consensus proposal for revised International Working Group response criteria for higher-risk MDS, the overall response rate (ORR) was 62.2% (28/45), with the complete response rate (CR) was 33.3% (15/45). For twenty-five naïve MDS, the ORR was 68% (17/25) and the CR rate was 32% (8/25). In nonfirst-line patients, the ORR and CR were 55% (11/20) and 35% (7/20) respectively. The median cycle to best response was 1 (1-4). ②With a median followup of 189 days, the median overall survival (OS) time was 499 (95% confidence interval, 287-711) days, and most patients died from disease progression. Responders had a significantly better median OS time than nonresponders (499 days vs 228 days, P<0.001). Multifactor analysis revealed that IPSS-R score and response to treatment were independent prognostic factors for OS; the presence of SETBP1 gene mutations was associated with a longer hospital stay (51.5 days vs 27 days, P=0.017) . Conclusions: There is clinical benefit of venetoclax in combination with hypomethylated agents in patients with higher-risk MDS, but adverse events such as severe hypocytopenia during treatment should be avoided.

Myelodysplastic Syndromes and Myelodysplastic Syndromes/Myeloproliferative Neoplasms: A Real-World Experience From a Developing Country.

Myelodysplastic syndromes (MDS) include a heterogeneous group of clonal bone marrow disorders characterized by ineffective hematopoiesis. They manifest as dysplasia in bone marrow hemopoietic elements associated with peripheral cytopenias with variable risk of AML transformation. We analyzed retrospectively registry data collected prospectively from patients with primary MDS and patients with MDS/myeloproliferative neoplasm (MPN) in the Jordan University Hospital between January 2007 and September 2021. The registry captured epidemiologic information such as date of diagnosis, age, gender, date of AML transformation, cytogenetics, MDS subtype, risk group according to Revised International Prognostic Scoring System, and survival. The registry also captured baseline ferritin, B12, and lactate dehydrogenase levels. A total of 112 patients with MDS and MDS/MPN were included in the registry. Median age at diagnosis was 59 years. The male-to-female ratio was about 1.2. In a multivariate cox regression model, baseline serum ferritin significantly affected survival as patients with levels exceeding 1,000 μg/L had a risk of death three times higher compared with those with <1,000 μg/L levels (P < .05). To our knowledge, our study is the first comprehensive study examining the epidemiology and prognostic factors in patients with MDS and patients with MDS/MPN in Jordan. Our results show that MDS and MDS/MPN epidemiology in Jordan is different compared with Western countries. Our results also show that baseline serum ferritin levels can be used as a prognostic marker for patients with MDS.

Myelodysplastic syndromes del(5q): Pathogenesis and its therapeutic implications.

Myelodysplastic syndromes (MDS) encompass a heterogeneous set of acquired bone marrow neoplastic disorders characterized by ineffective hematopoiesis within one or more bone marrow lineages. Nearly half of MDS patients carry cytogenetic alterations, with del(5q) being the most prevalent. Since its first description, del(5q) was consistently correlated with a typical clinical phenotype marked by anemia, thrombocytosis, and a low risk of evolving into acute leukemia. Presently, the World Health Organization (WHO) classification of myeloid neoplasms recognizes a specific subtype of MDS known as "myelodysplastic neoplasm with low blast and isolated del(5q)" identified by the sole presence of 5q deletion or in combination with one other abnormality excluding -7/del(7q). Several studies have sought to unravel the biological processes triggered by del(5q) in the development of MDS, revealing the involvement of various genes localized in specific regions of chromosome 5 referred to as common deleted regions (CDR). This intricate biological landscape makes the MDS cells with del(5q) exceptionally sensitive to lenalidomide. Several studies have confirmed the efficacy of lenalidomide in this context. Regrettably, the response to lenalidomide is not conclusive, prompting ongoing research into biological mechanisms that drive patients toward leukemia and strategies to circumvent lenalidomide resistance and disease progression.

Post Allogeneic Stem Cell Transplant Outcomes Following Response to Hypomethylating Agent Therapy in Myelodysplastic Syndromes Are Predicted By Persistent International Prognostic Scoring System-Molecular Risk

Introduction: The International Prognostic Scoring System-Molecular (IPSS-M) ( Bernard NEJM Evidence 2022) and the 2023 International Working Group (IWG) response criteria for myelodysplastic syndrome (MDS) ( Zeidan Blood 2023) are used to more accurately assess prognosis and therapeutic response in MDS. However, it is unknown if these tools can be used to predict outcomes post-allogeneic hematopoietic stem cell transplant (HCT). We sought to understand the impact of pre-HCT IPSS-M on post-HCT outcomes in patients (pts) with MDS who responded to hypomethylating agent (HMA) therapy. Methods: Pts with MDS treated with HMA (azacitidine or decitabine) who received an HCT post-HMA at Dana-Farber Cancer Institute from January 2014 to December 2020 were included. Response to HMA was assessed by 2023 IWG response criteria and was defined as complete remission (CR) + CR with bi-lineage blood count recovery (CRbi) + CR with uni-lineage blood count recovery (Cruni) + CR with partial hematological recovery (CRh). Combined clinical and molecular risk was assessed by IPSS-M at times of diagnosis and of HCT, the latter using the bone marrow biopsy and sequencing data collected closest to HCT. High risk was defined as IPSS-M moderately high, high, and very high, whereas low risk was defined as IPSS-M very low, low, and moderately low. Results: A total of 148 pts with MDS who received HMA and underwent subsequent HCT were included. Median age was 64 years (range 26-79) and 61.5% were men. Pts were diagnosed with MDS-EB1 (26.4%), MDS-EB2 (45.3%), and other MDS subtypes (28.3%). IPSS-M at time of diagnosis was very low (2%), low (10.1%), moderate low (6.1%), moderate high (8.8%), high (31.8%), and very high (22.3%). IPSS-M pre-HCT was very low (12.8%), low (8.8%), moderate low (10.8%), moderate high (12.8%), high (20.3%), and very high (10.8%). IPSS-M at diagnosis and pre-HCT could not be calculated because of missing molecular data in 18.9% and 23.6% of pts, respectively. Pts received a median of 4 HMA cycles (range 1-20) and were treated with azacitidine for 7 days (54.1%), decitabine for 5 days (39.2%), and other schedules (6.7%). Prior to HCT, IWG 2023 responses were: CR (15.5%), CRbi (14.9%), CRuni (19.6%), CRh (0.7%), partial remission (PR: 1.4%), hematological improvement (HI: 9.5%), and no response (38.5%). Most pts received HCT from either a matched unrelated (60.8%) or matched related donor (18.2%) with reduced intensity conditioning (74.3%). Pts received graft versus host disease prophylaxis with tacrolimus (tac)/methotrexate (MTX) (54.7%), tac/MTX/sirolimus (19.6%), post-transplant cyclophosphamide/mycophenolate mofetil/tac (15.5%), tac/sirolimus (8.1%), other (2%). Median HCT-comorbidity index (CI) was 2 (range 0-13) and 48.6% pts had HCT-CI ≥ 3. For the entire cohort, the median follow-up time among ongoing survivors was 48.3 months (range 5.5-101.3). Among pts who responded to HMA per IWG 2023 criteria (CR/CRbi/CRuni/CRh), those who had high risk by IPSS-M prior to HCT had significantly shorter median overall survival (OS) (27 months; 95% CI 7.5-51) compared to pts with a low risk by IPSS-M (not reached; p=0.016) ( Figure A). Cumulative incidence of relapse (CIR) at 4 years was 66% for pts with high risk and 31% for low risk (p=0.034) ( Figure B). Pts with response to HMA with high risk by IPSS-M had lower OS (4-year OS: 27% versus 53%; p=0.016) and progression-free survival (4-year PFS: 19% versus 50%; p=0.018) but similar non-relapse mortality (NRM) (4-year NRM: 16% vs. 19%; p=0.66) post-HCT compared to pts with low risk at time of HCT. Conclusion: For pts with MDS who achieve a response to HMA prior to HCT, combined clinical/molecular risk, as assessed by IPSS-M, has an important prognostic impact on post-HCT outcomes. Pre-HCT risk should be evaluated for prognostication and to guide patient care, including future prospective studies evaluating novel agents for post-HCT therapy.

A Simple Prediction Model of Outcomes after Allogeneic Hematopoietic Stem Cell Transplant (HCT) in Myelodysplastic Syndromes Using HCT-Comorbidity Index, Cytogenetic Risk, and Platelet Count

Introduction: Allogeneic hematopoietic stem cell transplant (HCT) is currently the only potentially curative option for patients (pts) with myelodysplastic syndromes (MDS). However, many pts relapse after HCT. While the International Prognostic Scoring System-Molecular (IPSS-M) is useful, next generation sequencing is not always available particularly in resource limited settings. Hence, we aimed to develop a prediction model utilizing readily available pt and HCT characteristics of post-HCT outcomes in pts with MDS treated with hypomethylating agent (HMA) therapy pre-HCT. Methods: Pts with MDS treated with HMA (azacitidine or decitabine) who received an HCT at Dana-Farber Cancer Institute from 01/2014-12/2020 were included. The primary outcome was progression free survival (PFS) post-HCT, defined as time from transplant to disease relapse or progression. Univariable analysis (UVA) and multivariable analysis (MVA) were used to identify predictors of PFS and build a model. Variables were pt age, sex, donor type (matched related donor (MRD) vs. matched unrelated donor (MUD) vs. 7/8 MUD vs. haploidentical), HCT-comorbidity index (HCT-CI), CMV status of donor/recipient, MDS subtype, graft versus host disease prophylaxis (GVHD ppx), HMA type, number of HMA cycles, conditioning intensity (myeloablative vs. reduced intensity), cell source (bone marrow vs. peripheral blood), response to HMA assessed by IWG 2023 criteria ( Zeidan Blood 2023), IPSS-Revised (IPSS-R) pre-HCT, and cytogenetic risk (very good, good, intermediate, poor, very poor) at diagnosis and pre-HCT. Results: A total of 148 pts with MDS received HMA and underwent subsequent HCT. Median age was 64 years (range 26-79) and 61.5% were men. Pts were treated with 7 days azacitidine (54.1%), 5 days decitabine (39.2%) and other schedules (6.7%) and received a median of 4 HMA cycles (range 1-20). Prior to HCT, IWG 2023 responses were: CR (15.5%), CRbi (14.9%), CRuni (19.6%), CRh (0.7%), PR (1.4%), HI (9.5%), and no response (38.5%). Most donors were MUD (60.8%) or MRD (18.2%), and most pts received reduced intensity conditioning (74.3%). GVHD ppx was tacrolimus (tac)/methotrexate (MTX) (54.7%), tac/MTX/sirolimus (19.6%), cyclophosphamide/mycophenolate mofetil/tac (15.5%), and other (10.1%). Median HCT-CI was 2 (range 0-13); 48.6% had HCT-CI ≥3. Median follow-up time among ongoing survivors was 48.3 months (range 5.5-101.3). The only statistically significant variables associated with post-HCT PFS in both UVA and MVA (with Cox MVA results shared here) were HCT-CI (≥4 vs. 0-3: HR 1.94, 95% CI 1.18-3.19, p=0.009), platelet count pre-HCT (platelets &amp;lt;40 vs. &amp;gt;70: HR 2.46, 95% CI 1.33-4.54, p=0.004; platelets 40-70 vs. &amp;gt;70: HR 1.84, 95% CI 1.02-3.32, p=0.044) and cytogenetic risk pre-HCT (very poor vs. other: HR 2.52, 95% CI 1.43-4.44, p=0.001). HCT-CI impacted non-relapse mortality (NRM) and not relapse whereas very poor cytogenetics impacted relapse and not NRM. A model predicting post-HCT outcomes was built with the following risk scores: HCT-CI: 0-3 (0), ≥4 (1.5); platelet count pre-HCT: &amp;gt;70 (0), 40-70 (1), &amp;lt;40 (2); cytogenetic risk pre-HCT: not very poor (0), very poor (2). Based on the sum risk score, patients were defined as low (0-1), intermediate (int) (1.5-2) or high (≥2.5) risk. The risk classification was significantly associated with post-HCT outcomes. Four-year post-HCT PFS was 68% (95% CI 56-78%), 36% (95% CI 22-51%) and 15% (95% CI 5-31%) for low, int and high risk, respectively (p&amp;lt;0.00001) ( Figure A). Accordingly, 4-year cumulative incidence of relapse was 23% (95% CI 14-33%) for low, 54% for int (95% CI 38-68%) and 62% for high (95%CI 39-78%) risk scores (p=0.00005). Four-year overall survival was 70% (95% CI 58-80%), 45% (95% CI 29-59%), and 19% (95% CI 7-36%) (p&amp;lt;0.00001), for the same respective risk groups ( Figure B). In contrast, NRM did not differ between risk categories (low: 9%, int: 10%, high: 23%; p=0.1). The predictability of this simple risk model (C-index: 0.72) was found to be superior to IPSS-R pre-HCT (C-index: 0.61) and IWG 2023 response pre-HCT (C-index: 0.617). Conclusion: We developed a simplified prognostic model of post-HCT outcomes for pts with MDS treated with HMA based on HCT-CI, platelet count, and cytogenetic risk post-HMA therapy and pre-HCT. We expect that this model will be particularly useful in resource-limited settings without easy access to next generation sequencing.

Subunit-Specific Analysis of Cohesin-Mutant Myeloid Malignancies Reveals Distinct Ontogeny and Outcomes

Introduction:Loss of function mutations in the cohesin complex ring components and modulators STAG2, RAD21, SMC1A, SMC3, and PDS5B are recurrent genetic drivers in myelodysplastic syndromes (MDS), acute myeloid leukemia (AML), and MDS/myeloproliferative neoplasm (MPN) overlap syndromes. However, whether different cohesin subunit mutations share disease characteristics and prognostic impact is not well understood. Methods: We assembled a cohort of 4,439 patients with hematologic neoplasms at the Dana-Farber Cancer Institute (DFCI) and the Munich Leukemia Laboratory (MLL), and identified a subset of 790 cohesin-mutant patients, the largest cohesin-mutant cohort to date. We performed a retrospective analysis of the incidence, clinical presentation, genomic landscape, and clinical outcomes in a cohesin subunit-specific way. Results: STAG2 mutations were most common and present in 610 cases (diagnosed as MDS (50%), AML (36%), MDS/MPN (10%)), followed by RAD21 in 104 (20% MDS, 64% AML, 2% MDS/MPN), SMC3 in 26 (35% MDS, 42% AML, no MDS/MPN), SMC1A in 22 (27% MDS, 55% AML, 5% MDS/MPN), PDS5B in 16 (13% MDS, 38% AML and 6% MDS/MPN), and 12 cases with more than one mutated cohesin gene (50% MDS, 33% AML, 8% MDS/MPN). Within the DFCI cohort, 256 (82%) patients were diagnosed with a myeloid malignancy and 55 (18%) patients with a non-myeloid hematologic malignancy. We focused our subsequent analysis on 735 patients diagnosed with MDS, MDS/MPN or AML, and compared them to 3,649 cohesin-wildtype (WT) patients in the DFCI and MLL cohorts. We found that STAG2 mutations were acquired at the MDS stage and were associated with MDS with increased blasts (75% cases with MDS-IB1 or IB2) and secondary AML. We also noted their co-occurrence with secondary AML-type mutations, such as ASXL1 (64%, OR=5.5, FDR=5e-29), SRSF2 (45%, OR=7.4, FDR=5-e31) and RUNX1 (37%, OR=3.5, FDR=2e-13), and trisomy 8 (OR=10.6, FDR= 2.2e-50). In contrast, mutations in RAD21, SMC1A, SMC3 and PDS5B shared features with de novo AML, including co-occurrence with NPM1 (32%, OR 4.3, FDR=1e-6) and FLT3 (23%, OR= 2.8, FDR= 0.01), and association of RAD21 and SMC1A with t(8;21) AML (OR= 131;134; FDR= 3.8e-5;4.1e-19). Of note, both STAG2 and RAD21 mutations shared a mutational exclusivity with TP53 mutations (OR=0.04-0.06, FDR &amp;lt; 0.001, Figure 1A). We next assessed the impact of different cohesin mutations on clinical outcomes. We conducted independent analyses of overall survival (OS) and progression free survival (PFS) in MDS and AML. Given our observations that cohesin mutations were mutually exclusive with TP53 mutations, and the established prognostic impact of TP53 mutations, we compared the overall survival (OS) and AML-free survival (PFS) of patients with STAG2-mutant MDS (n=119) to TP53-mutant MDS (n=280) and cohesin/ TP53-WT MDS (n=1,023). With a median follow-up (FU) of 51.1 months we observed a significantly worse OS of STAG2-mutant MDS compared to cohesin and TP53-WT MDS (HR 1.44, CI= 1.10-1.89, p=0.007) and a similar risk of leukemic transformation as TP53-mutant MDS cases (median AML-PFS of 15.4 months for STAG2, and 12.1 months for TP53, p=0.3). Furthermore, STAG2-mutant AML (n=148) had significantly worse OS than AML without myelodysplasia related changes (MR) (n=1384) (HR= 0.62, 95% CI=0.5-0.76, p&amp;lt;0.001, median FU 42.8 months), and similar outcomes as AML-MR without TP53 mutations (n=567), (HR=1.25, 95% CI= 1.01-1.55, p=0.04). Importantly, this pattern was distinct from outcomes of RAD21-mutant AML (n=39), which was almost identical to AML-non-MR and significantly better than STAG2-mutant AML OS (HR= 0.56, 95% CI= 0.34-0.93, p=0.024) ( Figure 1B). The effects of STAG2 and RAD21 mutations on OS remained significant when censored for allogeneic stem cell transplantation. Our findings suggest that only STAG2 mutations confer a negative impact on MDS and AML, and this is attributed to secondary ontogeny. Conclusions: In summary, our study establishes a role for different cohesin subunit mutations in distinct subtypes of MDS and AML, which has significant prognostic implications and expands our current understanding of this important group of driver genes. The findings from our subunit-specific analysis demonstrate that while STAG2 mutations are characterized by secondary AML ontogeny arising from MDS and associated with a worse prognosis, RAD21 mutations are associated with de novo AML and better survival.

Characteristics and Outcomes of Younger Adult Patients (Pts) with Myelodysplastic Syndromes (MDS): A Multicenter Retrospective Study

Introduction: MDS are primarily diseases of the elderly, with median age at diagnosis of 72 years. Focused data on clinical and molecular characteristics, as well as outcomes, in younger pts under age 60 years are limited. We conducted this multicenter retrospective study to describe pt characteristics, cytogenetic and molecular profiles, treatment modalities, and outcomes in younger pts with MDS, including adolescent and young adults (AYA). Methods: The study included pts diagnosed with MDS between 2002-2023 at 7 academic centers. We compared baseline characteristics, treatment, and outcomes of AYA (18-39 years) and younger adult (YA) pts (40-59 years). Responses were assessed using the modified IWG 2006 response criteria which included complete remission (CR), marrow CR (mCR), and hematologic improvement (HI). Wilcoxon rank sum test and Fisher's exact (and Chi-square) test were used to compare pt and disease characteristics for continuous and categorical variables, respectively. Overall survival (OS) was estimated using the Kaplan-Meier method and compared using log-rank test. Results: A total of 173 pts were identified (AYA, N=50; YA, N=123). Median age at diagnosis was 50 years (range, 18-59), with 51% females. Baseline characteristics are shown in Table 1. Therapy-related MDS (t-MDS) was observed in 40 pts (23%) with the remaining classified as de novo MDS (N=133; 77%). Inherited bone marrow failure syndromes were documented in 15 pts (9%), with Shwachman-Diamond Syndrome (N=4) and Fanconi anemia (N=4) being the most frequent. Using the WHO 2016 classification, the most common subtypes of MDS in both the AYA and YA cohorts were MDS with multilineage dysplasia (38% vs 19%), MDS with excess blasts-2 (MDS-EB) (24% vs 29%), and MDS-EB-1 (16% vs 20%). Similarly, using the WHO 2022 classification, the most common subtypes were MDS with low blasts (50% vs 21%), MDS with increased blasts-2 (MDS-IB-2) (24% vs 24%), and MDS-IB-1 (16% vs 18%). Stratifying pts using the IPSS-R cytogenetic (CG) risk group, the most common CG risk category identified was good CG (34% vs 52%, p=0.012). Poor/very poor CG were present in 34% and 37% of the AYA and YA groups, respectively. STAG2 and NRAS mutations occurred more frequently in the AYA pts compared to the YA group, while the YA cohort was enriched for the following mutations: TP53, DNMT3A, SF3B1, SRSF2, and TET2 (Figure 1). In the AYA population, 18 pts (38%) had very low/low, 10 (21%) intermediate, and 20 pts (42%) had high/very high risk MDS using IPSS-R. In the YA population, 32 pts (26%) had very low/low, 32 (26%) intermediate, and 57 pts (47%) had high/very high risk MDS using IPSS-R. Twenty-seven percent of pts with very low to intermediate-risk MDS using IPSS-R were upstaged to moderate high to very high-risk MDS using IPSS-M. The majority of pts (AYA: 75%; YA: 63%, p=0.5) were transfusion independent at baseline. Single-agent hypomethylating agents were the most frequently used frontline therapy, used in 17 AYA pts (34%) and 58 YA pts (48%), with more AYA pts receiving upfront allogeneic stem cell transplantation (Allo-SCT) compared to YA pts (28% vs 5%). After frontline therapy (Table 1), an additional 14 AYA (28%) and 52 YA (42%) pts received Allo-SCT. In pts with IPSS-R intermediate to very high-risk, response rates (HI+CR+mCR+mCR with HI) to frontline therapies were 46% and 54.5% in the AYA and YA groups, respectively. After median follow-up of 24 months [range, 1-218], median OS was numerically longer in the AYA versus YA group (155 vs 53 months, p=0.2). AML transformation occurred in 24% and 20% of the pts in the AYA and YA groups, respectively. Median OS was significantly longer in de novo compared to t-MDS pts (56 vs 27 months, p=0.03). Median OS among Allo-SCT compared to non-SCT pts were not reached vs 155 months ( p=0.9) in the AYA group and 53 vs 54 months ( p=0.4) in the YA group. IPSS-R (very low+low vs intermediate vs high+very high) was able to distinguish differences in OS in the YA (133 vs 53 vs 17 months, p=0.0002) and AYA (155 vs not reached vs 18 months, p=0.006) pts, with the exception of the intermediate-risk group in the AYA cohort. Conclusions: In this study, d e novoMDS was seen in the majority of younger pts with MDS (both AYA and YA). Mutations in STAG2 and NRAS were more common in the AYA pts, while YA pts had MDS more enriched for TP53, DNMT3A, TET2 and splicing mutations. This study is still ongoing with a plan to compare the abovementioned groups to older pts (≥60 years) with MDS.

UBA1 Mutations Identify a Rare but Distinct Subtype of Myelodysplastic Syndromes

Background Mutations in UBA1 are associated with VEXAS (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome, an adult-onset inflammatory disorder (Beck DB et al. NEJM 2020). Approximately 40% of VEXAS patients are also diagnosed with myelodysplastic syndromes (MDS). We previously profiled UBA1 p.M41 mutations in a select subset of the International Working Group for MDS (IWG-PM) cohort (Bernard E et al. NEJM Evid 2022) including 375 male patients lacking disease-defining mutations or established disease classification by WHO guidelines, and identified 28 patients (7%) with UBA1 p.M41T/V/L mutations (Cohort A, Sirenko M et al. Blood 2022). However, the prevalence and characteristics of UBA1 mutations in MDS have not been systematically evaluated in a representative MDS population. Methods We used targeted next-generation sequencing of the full UBA1 locus to profile 2027 diagnostic and treatment-naive MDS samples (Cohort B, 61% male) ascertained through the IWG-PM (Figure 1). Clinical associations of UBA1 mutations were evaluated and clinical history was reviewed for inflammatory conditions when available. Results In Cohort B, 35 UBA1 mutations in 34 (1.7%) patients were identified, of which 20 (0.97%) had likely pathogenic variants and 14 had variants of unknown significance (VUS). Likely pathogenic variants included 13 p.M41T/V/L mutation (variant allele fraction [VAF] range 0.013-0.94), and 7 non-p.M41 mutations where 6/7 had VAF&amp;gt;0.35: 2 with p.S56F (VAF 0.87 and 0.93), 2 p.A478S (VAF 0.72 and 0.80), 2 p.S621C (VAF 0.80 and 0.82) and 1 p.Y55H (VAF 0.025). Three VUS were in female patients. 204 cases were profiled by both assays and of those, all 8 ddPCR positive cases were identified by NGS with concordant VAF (R2=0.999 p&amp;lt;0.0001). Integration of Cohort A and B (n=2,198) yielded 40 patients (all male, median age 72; range 44-89 years) with pathogenic UBA1 variants. The WHO 2016 classification (available for n=38 of 40) was MDS-SLD/MLD (25), MDS-EB1 (4), MDS-U (3), CMML (2), MDS-RS-MLD (1), aCML (1), MDS/MPN-RS-T (1), MDS/MPN-U (1). Patients had a median of 1 myeloid gene mutation in addition to UBA1 (range: 0-4) with most frequent co-occurring events in TET2 (n=12), DNMT3A (n = 10), ASXL1 (n=3), SF3B1 (n=3) and loss of the Y chromosome (n=5). In 8 patients with pathogenic UBA1 &amp;gt; 2% VAF and co-occurring DNMT3A mutations, DNMT3A and UBA1 VAF were correlated (slope = 0.88, r = 0.87, p = 0.0005), suggesting that co-mutation may lead to clonal expansion. Conversely, TET2 co-mutations were either subclonal (n=4) or clonal (n=8) to UBA1. Among patients with pathogenic UBA1 variants, the majority had IPSS-M Very-Low/Low risk (73% 27/37). In contrast, patients with VUS were more likely to have Moderate or High risk (64% 7/11). Partial clinical history was available for 33 cases with pathogenic UBA1 variants. 50% (9/18) had inflammatory-rheumatic disease (IRD) including psoriatic arthritis, relapsing polychondritis, Sweet syndrome, bronchiolitis obliterans with organizing pneumonia, ear chondritis, and rosacea. 3 patients had more than one IRD. 8 were treated for IRD with steroids (n=6) or methotrexate (n=2). 4 patients had MGUS. Other manifestations included vacuoles (4/8), thromboembolic disease (5/16), non-infection fever (5/14), weight loss (4/14), ocular symptoms (5/15), arthralgia (3/16), chondritis (5/15), and other inflammation (6/14). IRD diagnosis usually preceded MDS (average time 0.28 years; range 16.5 years prior to 1.4 years after). Three patients transformed to acute myeloid leukemia (AML). One patient had a low VAF UBA1 p.M41V (0.0002 by ddPCR) and TET2, SF3B1, FLT3, and ASXL2 co-mutations at baseline. The second had UBA1 p.S56F (VAF 0.868) and a Chr 7q deletion. The third had VUS UBA1 p.R869L (VAF 0.222) and IRF1, NFE2 and RRAS co-mutations. Among the other UBA1-mutant patients that died or were censored after 1 year (n=37), none transformed to AML. Conclusion Within the large, representative, diagnostic and well-characterized IWG-PM MDS cohort, we find likely pathogenic UBA1 mutations in 1% of patients, with enrichment in male patients with few or no mutations in myeloid driver genes (7%). UBA1-mutant patients were predominantly IPSS-M low risk with a median of 1 additional mutation, usually in DNMT3A or TET2. UBA1 mutations may define a distinct subset of MDS and its recognition in future guidelines will improve the management of patients with MDS/VEXAS overlap.

Impact of Hypomethylating Agents on Cardiovascular Disease Risk Among Patients with Myelodysplastic Syndromes

Introduction: The association between clonal hematopoiesis (CH) and cardiovascular disease (CVD) risk has drawn attention to cardiovascular outcomes in myelodysplastic syndromes (MDS). CVD accounts for 25% of deaths in MDS, potentially via CH-mediated accelerated atherosclerosis from inflammatory vascular responses. We previously demonstrated that MDS was independently associated with increased risk of CVD in older adults from SEER-Medicare. We subsequently hypothesized that treatment with hypomethylating agents (HMA) could reduce CVD risk by ameliorating CH clones and reducing the inflammation. In this study, we aimed to define the impact of HMA on incident cardiovascular events among older adults with MDS. Methods: We identified subjects ≥66 years diagnosed with MDS from 2007 to 2017 in SEER-Medicare. Exclusion criteria including lacking continuous Medicare parts A, B, and D, enrolled in HMO, or incomplete follow-up. Demographics included age, sex, race, rurality, socioeconomic quintile, marital status, and geographic region. Baseline CVD risk factors, defined from ICD-9/10 codes, included hypertension, hyperlipidemia, diabetes, atrial fibrillation, pre-existing cardiac disease, obesity, and smoking. MDS factors, defined using HCPCS codes, ICD-O-3 codes and prescription records, included MDS subtype and histologic risk stratification, transfusion dependence and treatment with hypomethylating agents (HMA), lenalidomide, or erythropoietin-stimulating agents (ESA) as time-varying variables. Incident CVD was defined as new myocardial infarction (MI) and/or ischemic stroke occurring after MDS diagnosis, using published ICD-9/10 algorithms. We controlled for confounding using 2 complementary analytic approaches. First, we assessed the association between HMA use and CVD using propensity score adjusted cause-specific competing risk Cox hazard models with death as competing risk, Second, we used a case-crossover design with conditional logistic regression, in which subjects with CVD served as their own controls, using a 3-month HMA treatment window and a control period 6 months prior to the incident event. Results: We identified a cohort of 15,227 eligible patients with MDS. Of these, 1,125 patients had an MI and/or ischemic stroke within 1 year before MDS diagnoses and were excluded. We analyzed 14,102 MDS patients, with median age 82 years (IQR 77 - 86), who were predominantly male (53.8%), non-Hispanic white (88.6%), and from urban/suburban areas (86.2%). MDS was of low, intermediate, and high histologic risk in 14.7%, 72.8%, and 12.5%, respectively, and 28.6% were transfusion dependent. Pre-existing CVD risk factors at time of MDS diagnosis were present in 12,538 patients, with baseline cardiovascular risk defined as low, intermediate, and high in 11.1%, 32.3%, and 56.6% of the cohort. The cumulative incidences of MI, ischemic stroke and composite CVD events were 11.3%, 10.6% and 20.4%, respectively. The propensity score (PS) conditional probability for being treated with HMA included demographic variables, CVD risk factors, MDS histology and transfusion dependence. Our PS model adequately predicted HMA treatment propensity (AUC 0.76). Cause-specific regression with death as competing risk, adjusted for PS and other MDS-specific treatments (ESA and lenalidomide), showed no significant effect of HMA on the risk of composite CVD events, MI, or ischemic stroke (Table 1). Conditional logistic regression in the case-crossover analysis of 1,907 patients with composite CVD events showed no significant effect of HMA. Results were similar for analysis of patients with MI and ischemic stroke (Table 2). Conclusions: No study has previously investigated the effect of HMA therapy on cardiovascular outcomes in patients with MDS. We demonstrate that HMA therapy is not associated with a significant risk reduction in cardiovascular events among patients with MDS patients from the SEER-Medicare database. These results show that HMA therapy is unlikely to reduce cardiovascular mortality and underscore the need for alternative therapeutic strategies targeting cardiovascular health patients with MDS.

MDS/CMML from resource-limited region: Characteristics and comparison to tertiary reference European center.

Myelodysplastic Syndromes (MDS) and Chronic Myelomonocytic Leukemia (CMML) are clonal myeloid malignancies, characterized by bone marrow failure leading to cytopenias (and possible myeloproliferation for CMML) and a high propensity to evolve to Acute Myeloid Leukemia (AML). The aim of our retrospective study was to evaluate the clinical and hematological features; the prevalence of MDS subtypes, R-IPSS, and the outcome of 106 Armenian MDS/CMML patients diagnosed over the 2008-2020 period in a single Armenian Hematology center and compare them to French MDS patients included in the GFM registry. Median age in the Armenian cohort was 64 years (range 19-84) and 55% were males. The main MDS subtypes were MDS-MLD (29.2%) and MDS-SLD (27.3%), the least frequent was del 5q (0.9%). By comparison, a higher prevalence of MDS-MLD, MDS-EB2, and MDS-RS was found in the French cohort. Armenian patients' cohort generally had poor access to standard MDS treatment and 42.3% of the patients were transfusion dependent. Overall survival, however, did not significantly differ between Armenian and French cohorts. Our study stresses issues regarding epidemiology, access to diagnosis, difficulties of risk stratification, and access to treatment.

P92 Cutaneous manifestations of myelodysplastic syndrome: a systematic review

Abstract A variety of associations between cutaneous manifestations and myelodysplastic syndrome (MDS) have been described, but the frequency is unknown. The presence of cutaneous manifestations may have therapeutic and prognostic significance, as the presence thereof has been reported to be associated with poor prognosis or acute myeloid leukaemia (AML) progression, or may precede the diagnosis of MDS [Farah C, Bulai Livideanu C, Jegu J et al. Prevalence and prognostic value of cutaneous manifestations in patients with myelodysplastic syndrome. J Eur Acad Dermatol Venereol 2010; 24:1171–5; Ghoufi L, Ortonne N, Ingen-Housz-Oro S et al. Histiocytoid Sweet syndrome is more frequently associated with myelodysplastic syndromes than the classical neutrophilic variant: a comparative series of 62 patients. Medicine (Baltimore) 2016; 95:e3033]. We aimed to determine the types and prevalence of cutaneous manifestations in MDS, treatment options and prognosis associated with specific cutaneous manifestations and MDS subtypes. PubMed, MEDLINE and Embase were searched from inception up to 26 January 2023 for studies reporting cutaneous manifestations of MDS in adults aged ≥ 18 years, as per the World Health Organization classification. Case reports and case series were included. The review was registered with PROSPERO (CRD42021293140). In total, 92 studies were included (case reports n = 71, case series n = 21), consisting of 140 patients [98 male, mean age 61.0 (SD 15.4)]. We identified six common cutaneous manifestations: neutrophilic, e.g. Sweet syndrome and pyoderma gangrenosum (n = 66); vasculitis, e.g. leucocytoclastic vasculitis and Behçet disease (n = 21); granulomatous, e.g. granuloma annulare and interstitial granulomatous dermatitis (n = 8); connective tissue disease (CTD), e.g. dermatomyositis (n = 7); panniculitis (n = 4); immunobullous (n = 2); and other (n = 30). Sweet syndrome (81.8%) and pyoderma gangrenosum (18.2%) were the commonest presentations of neutrophilic dermatosis. Cutaneous features either occurred at time of MDS diagnosis in 24.7%, preceded the diagnosis in 36.1% (mean 17 months; range 0.5–216), or after diagnosis in 39.2% (mean 20.6 msonths; range 1–132). Prognosis was poor (40.2% death) with 34.1% progressing to acute myeloid leukaemia (AML), 50% of which had neutrophilic dermatosis. Death occurred in 38.5% of neutrophilic dermatoses (median time from onset of cutaneous manifestation: 12 months), 50% of vasculitis (7.5 months), 62.5% of granulomatous (15.5 months), 14.3% of CTD (7 months), and none reported in immunobullous and panniculitis. Granulomatous skin lesions had the poorest prognosis, 60% of which had progressed to AML. This systematic review highlights the range of cutaneous manifestations associated with myelodysplastic syndrome. Of note, we found that the majority of cases progressing to AML were associated with neutrophilic dermatoses overall; however, granulomatous skin lesions had the poorest prognosis with the highest proportion progressing to AML. We speculate that these manifestations may confer an increase in risk of transformation, compared with other cutaneous changes.

Juvenile myelomonocytic leukemia: A national analysis of demographic features.

e19086 Background: Juvenile Myelomonocytic Leukemia (JMML) is a rare hematological cancer originating in the bone marrow. It is a type of myelodysplastic syndrome (MDS) characterized by abnormal production of myeloid progenitor cells and monocytes. This malignancy is predominant in males, has a median age of diagnosis of 2 years, and carries a poor prognosis. It only accounts for 1% of all pediatric leukemias but constitutes 20-40% of pediatric MDS cases, making it the most common MDS subtype in children. Hematopoietic stem cell transplant (HSCT) is the only known cure for JMML, but its efficacy is just 50%. Without treatment, patients survive for a median of 10-12 months. Given the rarity of JMML, an analysis of demographic trends could offer valuable epidemiological insight. The National Cancer Database (NCDB) database was used to examine major demographic features of JMML. Methods: A retrospective analysis of all patients diagnosed with JMML between 2004 – 2020 in the NCDB (N = 242) was performed. Demographic factors including sex, race, Hispanic ethnicity, household income status, insurance status, urban/rural status, and Charlson-Deyo score were examined by descriptive statistics. Treatment statistics were also analyzed. Linear regression was used to determine incidence trends. Results: A total of 242 patients were identified with a histologically-confirmed diagnosis of JMML. Most patients were male (67.4%). The average age of diagnosis was 2 years (SD = 3.69, range = 0-33). The average incidence was 14.2 patients diagnosed per year (SD = 3.7, range = 9 – 21, R2 = 0.131). 93.8% had a Charlson-Deyo comorbidity score of 0. The majority of patients were White (74.4%), followed by Black (11.6%). 16.1% of patients were of Hispanic ethnicity. The distribution of median household income was 27.4% in the top quartile, 26.9% in the second, 26.9% in the third, and 18.7% in the fourth. Most patients were either privately insured (49.6%) or insured by Medicaid (42.6%). 75.5% of patients lived in a county with 250,000 people or more. Most patients received treatment (84.6%), while some only received active surveillance (8.7%) or no treatment (6.7%). Conclusions: This is the first NCDB analysis describing the demographic trends of JMML. Patients were twice as likely to be male than female. They were most likely to be White, with an average age of 2 years. This data reflects the expected age group and sex/race predominance described in the literature. The proportion of Hispanic JMML patients was comparable to Hispanics in the general US population. JMML appeared to be nearly evenly distributed among the top three household income quartiles. The lowest income quartile and rural inhabitants were least affected by this disease, which may indicate underdiagnosis in these populations. Further studies are needed to better define the relevance of these individual factors in the diagnosis, treatment, and survival of patients with JMML.

Inactivation of p53 provides a competitive advantage to del(5q) myelodysplastic syndrome hematopoietic stem cells during inflammation.

Inflammation is associated with the pathogenesis of myelodysplastic syndromes (MDS) and emerging evidence suggests that MDS hematopoietic stem and progenitor cells (HSPC) exhibit an altered response to inflammation. Deletion of chromosome 5 (del(5q)) is the most common chromosomal abnormality in MDS. Although this MDS subtype contains several haploinsufficient genes that impact innate immune signaling, the effects of inflammation on del(5q) MDS HSPC remains undefined. Utilizing a model of del(5q)-like MDS, inhibiting the IRAK1/4-TRAF6 axis improved cytopenias, suggesting that activation of innate immune pathways contributes to certain clinical features underlying the pathogenesis of low-risk MDS. However, low-grade inflammation in the del(5q)-like MDS model did not contribute to more severe disease but instead impaired the del(5q)-like HSPC as indicated by their diminished numbers, premature attrition and increased p53 expression. Del(5q)-like HSPC exposed to inflammation became less quiescent, but without affecting cell viability. Unexpectedly, the reduced cellular quiescence of del(5q) HSPC exposed to inflammation was restored by p53 deletion. These findings uncovered that inflammation confers a competitive advantage of functionally defective del(5q) HSPC upon loss of p53. Since TP53 mutations are enriched in del(5q) AML following an MDS diagnosis, increased p53 activation in del(5q) MDS HSPC due to inflammation may create a selective pressure for genetic inactivation of p53 or expansion of a pre-existing TP53-mutant clone.

Genome-wide analysis toward the epigenetic aetiology of myelodysplastic syndrome disease progression and pharmacoepigenomic basis of hypomethylating agents drug treatment response

Myelodysplastic syndromes (MDS) consist of a group of hematological malignancies characterized by ineffective hematopoiesis, cytogenetic abnormalities, and often a high risk of transformation to acute myeloid leukemia (AML). So far, there have been only a very limited number of studies assessing the epigenetics component contributing to the pathophysiology of these disorders, but not a single study assessing this at a genome-wide level. Here, we implemented a generic high throughput epigenomics approach, using methylated DNA sequencing (MeD-seq) of LpnPI digested fragments to identify potential epigenomic targets associated with MDS subtypes. Our results highlighted that PCDHG and ZNF gene families harbor potential epigenomic targets, which have been shown to be differentially methylated in a variety of comparisons between different MDS subtypes. Specifically, CpG islands, transcription start sites and post-transcriptional start sites within ZNF124, ZNF497 and PCDHG family are differentially methylated with fold change above 3,5. Overall, these findings highlight important aspects of the epigenomic component of MDS syndromes pathogenesis and the pharmacoepigenomic basis to the hypomethylating agents drug treatment response, while this generic high throughput whole epigenome sequencing approach could be readily implemented to other genetic diseases with a strong epigenetic component.

Improving the diagnosis of myelodysplastic syndrome by red blood cell parameters.

To investigate the value of red blood cell parameters in Myelodysplastic syndrome (MDS) diagnosis and their relations to MDS subtypes and risk groups. The red blood cell parameter [mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width (RDW)] levels [203 MDS, 99 aplastic anemia (AA), 145 megaloblastic anemia (MA)] were collected from a single-center retrospective cohort. The cut-off values, area under the receiver operating characteristic curve (ROC) curve (AUC), sensitivity and specificity of the four parameters were calculated from the ROC. Furthermore, Kruskal-Wallis test and Dunn's Test were performed to determine erythrocyte parameters in different subtypes and prognostic risks MDS. There are significant statistic differences in RDW (P < 0.001), MCH (P = 0.036) and MCHC (P < 0.001) (MDS vs AA); RDW (P = 0.009), MCV (P < 0.001), MCH (P < 0.001) and MCHC (P = 0.001) (MDS vs MA); MCV (P = 0.011) and MCH (P = 0.008) (higher-risk MDS vs lower-risk MDS). Between MDS and MA, the area under the receiver operating characteristic curve (ROC) curve (AUC) values of MCV, MCH, MCHC, RDW were 0.846, 0.855, 0.617, and 0.593. Between MDS and AA, the AUC values of MCH, MCHC, RDW were 0.609, 0.671, and 0.662, respectively. The red blood cell parameters contribute to the differential diagnosis of MDS, AA and MA and are related to MDS subtypes and risk groups.

Distinct Clinical and Prognostic Features of Myelodysplastic Syndrome in Patients from the Middle East, North Africa, and Beyond: A Systemic Review.

Myelodysplastic syndrome (MDS) describes a group of bone marrow malignancies with variable morphologies and heterogeneous clinical features. The aim of this study was to systematically appraise the published clinical, laboratory, and pathologic characteristics and identify distinct clinical features of MDS in the Middle East and North Africa (MENA) region. We conducted a comprehensive search of the PubMed, Web of Science, EMBASE, and Cochrane Library databases from 2000 to 2021 to identify population-based studies of MDS epidemiology in MENA countries. Of 1935 studies, 13 independent studies published between 2000 and 2021 representing 1306 patients with MDS in the MENA region were included. There was a median of 85 (range 20 to 243) patients per study. Seven studies were performed in Asian MENA countries (732 patients, 56%) and six in North African MENA countries (574 patients, 44%). The pooled mean age was 58.4 years (SD 13.14; 12 studies), and the male-to-female ratio was 1.4. The distribution of WHO MDS subtypes was significantly different between MENA, Western, and Far East populations (n = 978 patients, p < 0.001). More patients from MENA countries were at high/very high IPSS risk than in Western and Far East populations (730 patients, p < 0.001). There were 562 patients (62.2%) with normal karyotypes and 341 (37.8%) with abnormal karyotypes. Our findings establish that MDS is prevalent within the MENA region and is more severe than in Western populations. MDS appears to be more severe with an unfavorable prognosis in the Asian MENA population than the North African MENA population.

Digital image analysis of erythroblastic islands in myelodysplastic syndromes.

Myelodysplastic syndromes (MDS) encompass a diverse group of myeloid neoplasms for which the diagnosis of low-grade subtypes remains challenging. Erythroblastic islands (EBIs) are highly organized units of erythroid proliferation, differentiation, and enucleation. EBI disruption is frequently observed and is believed to be one of the early changes in MDS. In this study, we digitally analyzed bone marrow biopsies dual stained with alpha-hemoglobin stabilizing protein (AHSP) and CD163 to quantitatively study features of EBIs in MDS, among MDS subtypes, as well as those in normal marrows and marrows with other causes of anemia. EBIs in MDS specimens were smaller in size and higher in density compared to both normal and non-MDS anemia specimens. Increased CD163 expression within the EBIs is observed in both MDS and other causes of anemia. A combination of increased EBI density and CD163 expression is seen in association with MDS with high-risk cytogenetics and multiple adverse mutations. As a proof-of-concept study, we show that EBI features can be relatively easily quantified with AHSP/CD163 dual immunohistochemistry and open-source imaging analysis software, highlighting those that are unique to MDS, and which may be prognostically relevant. Further studies of the measurable EBI features may provide valuable and novel tools to aid MDS diagnosis and prognostication in the era of digital pathology.

Molecular International Prognostic Scoring System (IPSS-M) in Myelodysplastic Syndromes Arising from Aplastic Anemia and Paroxysmal Nocturnal Hemoglobinuria

Clonal evolution to myelodysplastic syndromes (MDS) or acute myeloid leukemia represents the most serious late complication of patients with aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria (PNH). The majority of secondary MDS (sMDS) cases present high-risk features with chromosome 7 abnormalities and mutations in ASXL1, RUNX1, SETBP1, and RAS pathway genes as the most frequent molecular lesions. Other cases tend to show more favorable outcomes with distinct genomic architecture mainly driven by generally considered low-risk cytogenetic alterations (e.g., del(13q), del(20q)). Such heterogeneity of genomic makeup, the rarity of the disease, and the scarcity of information make the prognostication of sMDS challenging for routine clinical practice. In recognition of the growing role of somatic mutations, the Molecular International Prognostic Scoring System (IPSS-M) has been conceived to improve the precision of prognostication of prior schemes by adding objective molecular markers. Whereas validated on de novo and secondary/therapy-related cases, its applicability specifically on post-AA/PNH MDS has not yet been explored. Here, we applied IPSS-M to 69 sMDS with complete clinico-genomic information from a large multicenter dataset of 1008 AA/PNH patients, using a comparator cohort of primary MDS (n=1281). The median age at MDS progression was 63 years (IQR, 34-70), and most patients were male (M:F ratio 1.65). Despite low bone marrow blast percentages (median, 2; 0-7), 71% of patients showed high-risk features according to IPSS-R (scores >3.5), chiefly due to the enrichment of poor risk cytogenetics, most frequently monosomy 7. Overall, 48% of patients received disease-modifying treatments (DMT) with either HMA (28%), HSCT (60%) or both (12%). Leukemia progression was registered in 14% of cases after a median of 5.4 months (1-14) from sMDS onset. With a median follow-up of 55.6 months (95%CI, 42.5-75.8), the 60-month overall (OS) and leukemia free-survival (LFS) achieved 44% (32-60) and 42% (31-58), respectively. The IPSS-R distribution was as follows: Very Low (6%), Low (23%), Intermediate (30%), High (23%) and Very High (18%). By applying IPSS-M, patients were redistributed in Very Low (5%), Low (19%), Moderate Low (14%), Moderate High (14%), High (29%), and Very High (19%) risk categories. When comparing five-to-five (merging together the Moderate Low/High IPSS-M categories), 55% of cases were re-stratified, of which 63% up- and 37% down-staged (Fig.1A). Indeed, 77% of sMDS patients harbored at least 1 mutation with 43% presenting >2, thereby substantiating the differences observed between the two prognostication systems. Although according to IPSS-M the majority (62%) of sMDS cases still clustered in higher-risk categories, a non-negligible fraction (38%) was assigned to lower-risk groups. To further explore whether IPSS-M could be used to predict OS/LFS also in sMDS cases, we analyzed survival outcomes by taking advantage of a cohort of de novo cases. However, approximately half of sMDS received DMT, potentially generating a bias when using survival as a surrogate for outcomes comparisons, even in cases falling into equivalent risk categories. Therefore, we applied a propensity score matching by using age, gender and DMT as relevant covariates to reduce any possible confounder. As reported for others MDS subtypes in the original IPSS-M study, OS/LFS outcomes of sMDS paralleled those observed in the de novo group within the various IPSS-M risk categories (Fig.1B). We applied for the first time IPSS-M in a real-world cohort of sMDS, showing its potential for refining the assignment of patients into risk categories prognostic of disease outcomes. The actuarial survival of sMDS cases was not distinct from de novo patients matched for basic clinical features in equivalent IPSS-M risk groups. The complexity of the genomic landscape typical of AA/PNH clonal evolution makes sMDS a prototypic model whereby the incorporation of molecular information is of paramount importance to ensure adequate clinical management. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Extramedullary Hematopoiesis (EMH) and Myelodysplastic Syndrome (MDS): Review

Introduction: Extramedullary hematopoiesis (EMH) is the proliferation of hematopoietic tissue outside the bone marrow (BM). They are primarily seen in patients with chronic hemolytic anemia, for example, thalassemia and sickle cell disease. It's also reported with myeloproliferative neoplasms (MPN), especially in primary myelofibrosis. The mechanism behind it is the reactive and compensatory expansion of hematopoietic tissue outside the BM. EMH associated with myelodysplastic syndrome (MDS) has only been reported as case reports Methodology: A literature search was performed for English language articles using PubMed, Scopus, and Google Scholar, for any date up to June 2022. The following keywords were used "(Myelodysplasia), (Myelodysplastic syndrome), (MDS), (extramedullary hematopoiesis), (EMH)". Results: Fifteen cases were reported. Males were predominant with 12 (80%) patients, with a median age of 69 years. Complete blood count (CBC) showed a median hemoglobin (Hgb) of 8.5 g/dL, a median white blood cell count of 8 x109/L, and a median platelet count of 165 x109/L. MDS subtypes were ring sideroblasts in 6 (40%) patients and MDS/MPN in 4 (26%) patients. The most common affected site was para-spinal area in 7 (46%) patients, while other areas includes the mediastinum, lung, skin, pericardium, spleen, liver, brain, and lymph nodes. Computed tomography (CT) was the most common used imaging modality for diagnosis in 7 (46%) patients, followed by a biopsy to the affected site in most cases. Five (33%) patients received surgical treatment, 4 (26%) radiation therapy and 3 (20%) steroids treatment. TreatmenResponses to interventions showed improvement in 8 (53%) patients. Two patients' conditions remained stable while another two progressed. For overall survival, six (40%) patients reported alive and four (26%) dead. The average duration of follow-up for the cases was nine months. Conclusion: MDS associated Extramedullary hematopoiesis (EMH) is extremely rare. However, it should be thought of and kept in mind as a differential diagnosis. Early diagnosis and management is warranted as it could involve vital organs leading to increase morbidity and mortality. There is no consensus or guidelines for treatment so far. Male with anemia and ring sideroblasts MDS type were more frequent and can be considered as a risk factors for EMH in MDS. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

PD-1 Inhibitors Can be the First-Line Therapy for Myelodysplastic Syndrome (MDS) --Study on the Bone Marrow Immune Microenvironment of MDS By Multispectral Imaging of Multiplex Immunofluorescence

Objective: Myelodysplastic Syndrome (MDS) is a special myeloid neoplasm with still limited treatment choices and poor survival. Although current therapies including HMAs have been shown to prolong survival, only 40-50% of patients respond to therapy, and responses are universally transient, with loss of response within 2 years. With the increasing understanding of the pathogenesis of MDS in recent years, MDS was found closely associated with the bone marrow microenvironment, including immune microenvironment (IME). More and more evidences show that the immune microenvironment of MDS is related with its disease characteristics and prognosis. Knowing more of the IME of MDS may facilitate the diagnose and treatment on MDS. However, till now little was known about the bone marrow immune microenvironment of MDS. Previous studies mostly applied multiparameter flow cytometry and based on the PB samples or frozen bone marrow fluid samples, less was known about the immune landscape of MDS bone marrow biopsies. Methods: We use multispectral imaging of multiplex immunofluorescence (mIF) to analyze the bone marrow biopsy slides and explore the bone marrow immune microenvironment of MDS patients. A total of 20 de novo MDS patients, 20 post-treatment MDS patients and 20 normal controls were included in this study. In HMAs treated group, 10 patients were response to HMA and another 10 patients were not response. HMAs were either decitabine with a dose at 20mg/m2 d1-5 or 5-Azacytidine with a dose at 75mg/m2 d1-7. The multiplex staining panel could differentiate the distinct cell subpopulations into CD34+CD117+ cells, CD8+ cells, PD1+ cells, CTLA4+ cells, CD8+PD1+ cells and CD8+CTLA4+ cells, CD8-PD1+ cells and CD8-CTLA4+ cells, respectively. We analyzed the proportion of these cells in MDS patients and normal controls, and analyzed the proportion of these cells in MDS patients with different IPSS risk stratifications, and we also assessed the degree of myelofibrosis in MDS patients and analyzed the relationship between myelofibrosis and immune cells. Results: We found that compared with the normal control, the proportion of CD8+ cells in de novo MDS patients increased, and CD8+PD1+ T cells increased too, but the CD8+CTLA4+ T cells decreased. Compared with the lower-risk groups, CD8+ T cells as well as CD8+PD1+ T cells increased in higher-risk groups, while CD8+CTLA4+ T cells decreased. We also found a higher CD8+ T cells as well as CD8+/PD1+ T cells in MDS-F patients, especially in MDS-F patients with higher IPSS risk levels. We also found that compared with the normal control, the proportion of CD8+ T cells per CD34+CD117+ cell reduced, and was lower in IPSS int-2 risk/high-risk group than that in low-risk/int-1 risk group. But the proportion of CD8+PD1+/CD34+CD117+ increased compared with normal control. To analyze the bone marrow immune microenvironment after HMAs treatment, CD8+PD1+ T cells decreased in patients who are effective to HMAs, but still remain high in patients who had no response to HMAs, so did the proportion of CD8+PD1+/CD8+ and CD8+PD1+/CD34+CD117+. However, such findings were not found on CD8+/CTLA4+ T cells. Conclusions: Our research findings provide a new insight on the bone marrow IME of MDS. The results confirmed that the immune checkpoint molecule PD-1 positive CD8+ T cells are abundant in MDS IME and associated with the risk. However, CTLA4 may not be a major molecule interfere with the IME of MDS. Our result also suggest that PD-1 inhibitor combines with HMAs might be used as a first-line therapy for de novo MDS patients to cover those patients who may not have response to HMAs. Also, PD-1 inhibitor may cover higher risk MDS and MDS-F, the latter is a high-risk subtype of MDS. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal