Myelodysplastic Syndrome Del Research Articles

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.

Somatic Mutations and DNA Hypermethylation at Enhancers and Promoters Identify Distinct Subtypes within Lower-Risk Myelodysplastic Syndromes

Myelodysplastic syndromes (MDS) are a group of heterogeneous disorders caused by the accumulation of somatic mutations in the hematopoietic stem and progenitor compartment. Besides del(5q), SF3B1 or TP53 mutations, referred to as defining genetic abnormalities, mutation patterning hardly structured the classification of MDS. Mutations in epigenetic factors occur early in the development of clonal hematopoiesis leading to precocious alterations of DNA methylation implicated in oncogenesis. Convergent DNA methylation patterns related to both mutations and microenvironment imprinting may induce specific gene expression profiles and contribute to phenotypic variations. To refine a pathophysiological classification of lower-risk MDS, we combined genetic profiling to DNA methylation and transcriptome data. Methods: We enrolled 543 lower-risk treatment-naïve MDS patients at diagnosis and performed DNA-sequencing of 24 genes. DNA methylation and RNA-sequencing data were generated in a representative subset of 175 cases with available material (75 MDS-SLD/MLD, 40 MDS-EB1, 53 MDS-RS-SLD/MLD, 5 MDS del(5q), 2 MDS-U) and 7 age-matched healthy controls. IPSS-R was very low, low or intermediate in 87.4%. During a median follow-up of 2 years, 16% of MDS cases progressed to AML (MDSp). Infinium EPIC 850K array allowed after filtering the examination of methylation of 723,612 CpG sites with enrichment at enhancers and promoters. Differentially methylated regions with differentially methylated CpG sites (DMR-CpG) between cases and controls were defined with a minimum of 2 probes, a Benjamini-Hochberg-adjusted P-value cut-off of 0.05, a false discovery rate of 0.001 and a mean Δβ-value >20% at CpG sites. Consensus motifs for transcription factors were identified using Homer. Results: Unsupervised clustering on genetic profiling of 543 patients identified distinct subsets of lower-risk MDS with different clinical features: one cluster (group A) was enriched in del(5q), three clusters were characterized by SF3B1 mutations, either isolated (group B) or associated with DNMT3A (group E) or TET2 (group F), while the two remaining clusters were enriched in either complex pattern of mutations (group C) or SRSF2 mutations (group D). Genetic clusters showed significantly different clinical outcomes, clusters C, D and E having lower overall survival and higher risk of progression to high risk MDS or AML compared to other clusters. In the subset of 175 cases, a total of 2,953 unique DMR-CpGs allowed a robust repartition of patient samples in 4 groups using the k-means method. The 4 methylation groups were clinically distinct in terms of age, hemoglobin, neutrophils, monocytes, platelets, BM blasts, WHO classification, IPSS-R, and mutation pattern. A significant correlation was found between genetic and methylation groups ( P<0.001). Hypomethylated CpGs defined group 4 which was enriched in MDS-RSwith low blast count and few co-mutations, while groups 1 and 3 demonstrated hypermethylated profiles driven by TET2/ IDH1-2 mutations and TET2/ SRSF2 mutations, respectively. TET2-mutated cases exhibited an increased proportion of hypermethylated DMR-CpGs at enhancers (DME) significantly enriched in C/EBP and ETS family transcription factor motifs. In MDS without evidence of progression, we identified 1,418 DME and their gene targets of which those significantly deregulated in RNA-seq were involved in the control of translation and response to TGF-β. By contrast, in MDS with rapid progression to AML, DMR-CpGs were significantly enriched at CpG islands and promoters ( P<0.0001) and a set of 10-20 genes downstream of these promoters were specifically deregulated. Conclusion: Somatic mutations and DNA methylation at enhancers and promoters identify distinct subsets of lower-risk MDS with different clinical behavior. Hypermethylation at enhancers with C/EBP or ETS family motifs is a hallmark of MDS and may account for changes in transcription factor recruitment and cell fate. Hypermethylation of promoters with downstream effects on gene expression may indicate a propensity to rapid evolution to AML.

Real-world Data From the Swiss Lenalidomide in MDS del(5q) (SLIM)-Registry Identify New Chances and Challenges in Lenalidomide Treatment of Patients With MDS del(5q).

Real-world Data From the Swiss Lenalidomide in MDS del(5q) (SLIM)-Registry Identify New Chances and Challenges in Lenalidomide Treatment of Patients With MDS del(5q).

P771: PROGNOSTIC CHARACTERISTICS OF PATIENTS WITH MDS WITH ABERRATIONS OF CHROMOSOME 5. DATA FROM THE DÜSSELDORF MDS REGISTRY

Background: Myelodysplastic syndromes (MDS) are hematopoietic stem cell disorders with a wide spectrum of biological and clinical features. Up to 20% of MDS patients present with aberrations of chromosome 5, either as isolated del(5q) or combined with other aberrations. Patients with a medullary blast count < 5% and isolated del(5q), or with one additional aberration except anomalies of chromosome 7, are diagnosed as MDS del(5q), a defined entity according to the WHO 2016 classification. They have a favorable prognosis compared to other types of MDS, although profound anemia, chronic transfusion dependency and the risk of disease progression into AML present clinical challenges. Aims: We analyzed the prognostic impact of karyotype complexity in MDS del(5q). Methods: From the Düsseldorf MDS registry we retrieved 499 patients with MDS or CMML according to WHO 2016, who showed any kind of del(5q). Biological and clinical parameters such as karyotype, IPSS-R and type of treatment were evaluated. Survival and progression to AML was calculated using Kaplan-Meier-plots. Cox regression analysis was performed to identify disease-related prognostic factors. Patients were followed up until Dec 31th 2021. Results: 58% of the patients were female, median age was 67 years. Median medullary blast count was 4% (0-19%), and median survival in the entire group was 28 months. For assessing the natural course of disease, we screened for patients with non-intensive treatment only (best supportive care, lenalidomide, low-dose Ara-C, hydroxyurea). Separation by medullary blast count (< 5%, 5-9% or ≥ 10%) was associated with significantly different median survival times, ranging from 63 months in the first group to 3 months in patients with ≥ 10% medullary blasts (p < 0.001). Survival was also affected by the cytogenetic risk group according to IPSS-R. Patients in the low-risk group (median survival 72 months) differed significantly from patients in the very high risk group (median survival 5 months) (p < 0.001). A similar trend was observed according to karyotype complexity represented by number of aberrations apart from del(5q). Median survival of patients with an isolated del(5q) was 86 months, while patients with a complex karyotype (del(5q) and ≥3 additional aberrations) had a median survival of 5 months. Biological risk factors were assessed using Cox regression analyses. Considering overall survival as endpoint, medullary blast percentage, cytogenetic risk group, and complexity of the karyotype had a significant impact on survival (p < 0.001). In the entire patient cohort, as well as among patients receiving non-intensive treatment, the rate of AML progression was significantly influenced by karyotype complexity (p < 0.001). While the median time to AML progression in both isolated del(5q) and del(5q) combined with one aberration had not been reached at the end of the observation period, the median time to AML progression for patients with del(5q) as part of a complex karyotype was 31 months in the entire cohort and 14 months in the low-intensity treatment group. Image:Summary/Conclusion: Both the IPSS-R cytogenetic risk group and the complexity of the 5q- karyotype showed prognostic impact in patients with del(5q). This was true for overall survival as well as risk of AML progression. Regardless of therapy or medullary blast count in patients with del(5q), the risk of AML progression increased dramatically with increasing complexity of the 5q- karyotype.

Comprehensive Molecular Characterization of Myeloid Malignancies with 9q Deletion

Background and aims: Deletions in the long arm of chromosome 9, del(9q), are recurrent cytogenetic aberrations in myeloid neoplasms. While relatively common in patients with acute myeloid leukemia (AML), del(9q) occurs less frequently in other myeloid malignancies such as myelodysplastic syndromes (MDS) or myeloproliferative neoplasms (MPN). To present, cases with del(9q) in MDS and MPN are poorly characterized on a molecular level. We set out to define the size and minimally deleted region (MDR) of del(9q) as well as the spectrum of accompanying gene mutations in patients with MDS or MPN. Furthermore, the prognostic impact of del(9q) in MDS is still under debate. According to the revised international prognostic scoring system (IPSS-R), MDS patients with isolated del(9q) fall into the cytogenetic intermediate risk group (median overall survival, OS, of 32 months) based on the presence of a single aberration (Greenberg et al, Blood 2012). We therefore aim to evaluate if this risk stratification is appropriate for our patient cohort.Patients and methods: A total of 55 (26 female and 29 male) patients with MDS (n=40), MPN (n=8) and MDS/MPN overlap (n=7) were included in this study. The median age was 75 years (range: 23-94 years). Conventional cytogenetic analysis was performed for all patients. Cases (n=38) with sufficient clone size were investigated by array CGH (SurePrint G3 ISCA CGH+SNP Microarray, Agilent, Waldbronn, Germany). Mutation status was examined using an amplicon-based NGS panel targeting 40 genes commonly affected in myeloid neoplasia.Results: In 36/55 (65%) of patients, del(9q) was the sole cytogenetic aberration. Additional recurrent cytogenetic abnormalities included unbalanced rearrangements, n=8; del(5q), n=5; del(11q), del(20q), +8, +21 (n=2, each). Clinical follow-up data was available for 16 MDS patients with isolated del(9q), median OS was 35 months (range, 1- 91 months). In cases with array CGH data, size of the 9q deletion varied between 2.2 and 70.5 Mb (median, 33.9 Mb). We identified a MDR of 3.6 Mb ranging from genomic position 85,716,785 to 89,340,559 (UCSC hg19). A total of 21 genes are located in the MDR, including FRMD3, UBQLN1, KIF27, HNRNPK, SLC28A3 and NTRK2, which have previously been described in the MDR of del(9q) AML patients. Driver gene mutations were identified in 43/55 (78%) of patients. The number of mutated genes ranged from 1-5 (median: n=2). We did not observe significant differences in the number of mutated genes between younger or older patients (cut-off: 70 years), and patients with isolated del(9q) or additional cytogenetic aberrations. However, patients without evidence for a gene mutation (n=12) were significantly younger than patients with respective mutations (median age 70 vs. 76 years, p=0.014). Recurrently mutated genes included TET2 (39%), ASXL1 (31%), JAK2 (25%), U2AF1 (17%), RUNX1 (11%), EZH2 (8%), NRAS (7%), BCOR, KRAS, TP53 (6% each) and SRSF2 (5%). ASXL1 and TET2 were frequently co-mutated, as 12/20 (60%) of TET2 mutated cases also harbored ASXL1 mutations (p< 0.001). Overall, we identified a high prevalence of TET2 mutations in patients with del(9q). This association was even more pronounced when we limited our analyses to patients with isolated del(9q), where we observed a TET2 mutation frequency of 45%. In 7/31 (23%) of patients without TET2 mutation, other genes associated with epigenetic regulation, namely DNMT3A, ASXL1, EZH2, WT1, IDH1 and IDH2, were affected, underlining a high mutation rate (49% of total cohort) in this functional class. Mutations linked to the spliceosome machinery, SF3B1, SRSF2 and U2AF1, were mutated in 13/55 (24%) of patients in the total cohort and in 9/40 (23%) patients with MDS.Conclusions: Deletions in 9q are rare aberrations in MDS and MPN. Our analyses provide novel insights into the molecular profile of this cytogenetic subgroup. 1) Our patient cohort with MDS or MPN and del(9q) demonstrated a minimal deleted region in concordance with previous reports on the MDR of del(9q) AML patients, indicating a general pathogenic mechanism. 2) We identified gene mutations in 78% of our patient cohort, TET2 and other epigenetic regulators were mutated in 49% of patients with del(9q), suggesting cooperative pathogenic potential. 3) We observed a median OS of 35 months in patients with MDS and isolated del(9q), confirming the current stratification according to IPSS-R. [Display omitted] DisclosuresHartmann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Meggendorfer:MLL Munich Leukemia Laboratory: Employment. Fasan:MLL Munich Leukemia Laboratory: Employment. Stengel:MLL Munich Leukemia Laboratory: Employment. Zenger:MLL Munich Leukemia Laboratory: Employment. Zieschang:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Heterogeneous Landscape of RUNX1 Related Disorder: Four Families with Inherited Thrombocytopenias and Novel Genetic Variants in RUNX1 Associated to Relevant Clinical Complications

BackgroundFamilial platelet disorder with propensity to myeloid malignancy (FPD/AML) is a rare autosomal dominant disease with incomplete penetrance and variable expressivity. It is characterized by thrombocytopenia and/or platelet functional defects. Although bleeding tendency is usually mild to moderate, an important hallmark of FPD/AML is the increased risk of myeloid neoplasms, such as myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). The 2016 revision to the WHO classification system for myeloid neoplasms has incorporated a section on “myeloid neoplasms with germline predisposition” including RUNX1, ANKRD26 and ETV6 genes, among others. There is a great phenotypic heterogeneity and diagnosis is challenging due to specific test is not available. Now, high-throughput sequencing (HTS) is revolutionizing genetic diagnosis of human diseases, including platelet disorders and is extremely helpful to identify this disorder.AimsTo assess the clinical, platelet phenotype and their genetic defect of 4 unrelated families with RUNX1 related thrombocytopenia (RUNX1 -RT) in our cohort of 82 consecutive unrelated probands with inherited platelet disorders (IPDs).MethodsWe studied 5 patients from 4 unrelated families presenting with lifelong thrombocytopenia with normal platelet size. Clinical records were reviewed and bleeding scored with ISTH-BAT. Platelet phenotyping included peripheral blood smear and platelet aggregation. Patients DNAs were analyzed by HTS using a 71-gene panel related to IPDs. Causative variants were elucidated after a workflow algorithm filter based in quality, consequence-damaging, minor allele frequency <0.05 and in silico prediction tools. Finally, variants were qualified according to guidelines of the American College of Medical Genetics and Genomics and Association for Molecular Pathology.ResultsThe median age was 28 years old (1-54), median platelet counts was 90x103/mm3 (35-108x103/mm3) and bleeding score was 3 (2-5). Clinical and family history, and laboratory findings in these patients are shown in Figure 1. Family 1 (F1) showed an autosomal dominant thrombocytopenia (P1, P2, brother and their mother). In this family, a extremely history of hematologic malignancies are presented: one brother underwent to allogeneic transplant from unrelated donor due to a high-risk MDS del(7q) and one daughter of P1 died at the age of 13 years old due to a refractory AML. In F2, a lifelong thrombocytopenia, bleeding and family history of breast cancer was characteristic; but, in F3, only a lifelong thrombocytopenia was referred. Finally, P5 showed mental retardation, corpus callosum hypoplasia, facial and cardiac abnormalities and severe thrombocytopenia. HTS revealed three novel variants affected to RUNX1 (F1, P3 and P4) (Figure 1) and one sporadic germ line RUNX1 deletion involving chromosome 21q22, which, was confirmed by in-situ hybridization, resulting in RUNX1 haploinsufficiency. The missense variants affected to runt homology domain may lead to dominant-negative effects and were associated with higher propensity to develop AML, but it usually needed a second alteration associated, as occurs in our families (F1 and F2).ConclusionHTS facilitates genetic confirmation of FPD/AML diagnosis, and may help investigating phenotype-genotype relationships in this heterogeneous landscape. An earlier diagnosis of this disorder improves the genetic counselling and appropriate therapeutic management.FundingGerencia Regional de Salud [GRS 1370/A/16]; ISCIII & Feder (PI14/01956), CIberer CB15/00055, Sociedad Española de Trombosis y Hemostasia. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Blockade of IL-22 signaling reverses erythroid dysfunction in stress-induced anemias.

Patients with myelodysplastic syndromes (MDS) display severe anemia but the mechanisms underlying this phenotype are incompletely understood. Right open-reading-frame kinase 2 (RIOK2) encodes a protein kinase located at 5q15, a region frequently lost in MDS del(5q) patients. Here, we show that hematopoietic cell-specific haploinsufficient deletion of Riok2 (Riok2f/+Vav1cre) led to reduced erythroid precursor frequency leading to anemia. Proteomic analysis of Riok2f/+Vav1cre erythroid precursors suggested immune system activation and transcriptomic analysis revealed an increase in p53-dependent interleukin-22 (IL-22) in Riok2f/+Vav1cre CD4+ T cells (TH22). Further, we discovered that the IL-22 receptor, IL-22RA1, was unexpectedly present on erythroid precursors. Blockade of IL-22 signaling alleviated anemia not only in Riok2f/+Vav1cre mice but also in wild-type mice. Serum concentrations of IL-22 were increased in the subset of del(5q) MDS patients as well as patients with anemia secondary to chronic kidney disease (CKD). This work reveals a possible therapeutic opportunity for reversing many stress-induced anemias by targeting IL-22 signaling.

Impaired Formation of Neutrophil Extracellular Traps (NETs) in Patients with Myelodysplastic Syndrome (MDS)

Introduction Increased susceptibility to infections in MDS is due to neutropenia as well as functional impairment of neutrophils. We investigated whether neutrophil dysfunction includes diminished formation of neutrophil extracellular traps (NETs). The latter are networks of extracellular fibers, primarily composed of DNA, which bind pathogens. This component of the immune system's first line of defense was first described in 2004 by Zychlinsky and coworkers. Formation of NETS is triggered by reactive oxygen species (ROS), which in neutrophils are mainly produced by NADPH-oxidase and myeloperoxidase (MPO). Methods Fluorescence microscopy was used to show NET formation in patients with MDS (n=12) (1 MDS del(5q), 1 MDS-RS-SLD, 1 MDS-RS-MLD, 5 MDS-MLD, 2 MDS-EB-1, 2 MDS-EB-2) in comparison to an age-adjusted normal control group (n=15). Neutrophils were isolated from peripheral blood by density gradient centifugation, sedimented on cover slips in 24-well plates, and incubated with phorbol-12-myristate-13-acetate (PMA) for 30 and 180 minutes to stimulate NET formation. Neutrophil elastase was detected by primary anti-NE (Abcam) plus secondary goat anti-rabbit Alexa 488 (FITC), histones by primary anti-histone (Millipore) plus secondary goat anti-mouse Alexa 568 (PE), and cell nuclei by DNA staining with DAPI. Fluorescent images were loaded into Image J/FIJI Software (https://imagej.nih.gov/ij/) for automatic cell detection and assessment of the proportion of cells undergoing NET formation, detectable by positive histone staining. Flow cytometry was used to further characterize NET formation and demonstrate the production of ROS by NADPH-oxidase and MPO. Intracellular MPO staining was positive for 96.7% and 99.1% of neutrophils in controls and MDS patients, respectively. Reactive oxygen species (ROS) were detected using dihydro-rhodamin 123 (DHR) for hydrogen peroxide, hydroethidine (HE) for superoxide anion, and 3`-(p-aminophenyl) fluorescein (APF) and 3`-(hydroxyphenyl) fluorescein (HPF) for hypochloride (HOCl). In order to block certain components of cellular ROS production, the following inhibitors were used: 4-aminobenzoic hydrazide (ABAH) to block MPO; 4-dimethylamino-antipyrine (AP) to block MPO and quench ROS; and diphenylen-iodonium chloride (DPI) to inhibit NADPH oxidase and mitochondrial respiratory complex I. Flow cytometry data were analysed using CellQuest Software (Becton Dickinson) and FCS Express Reader (De Novo Software). Results By fluorescence microscopy, marked morphological abnormalities of NET formation were observed. PMA-stimulated neutrophils of patients with MDS generated significantly fewer NETs than neutrophils from controls (increase from 17% to 67% vs. increase from 17% to 85% of cells, respectively) (p=0.02), see Fig. 1. MDS neutrophils showed significantly less cellular swelling after stimulation with PMA (p=0.04). Histone staining showed a more condensed chromatin in MDS neutrophils prior to stimulation (smaller mean fluorescence intensity (MFI) for PE; p=0.05). Upon stimulation with PMA, the decrease in MFI of DAPI, indicating chromatin decondensation, was significantly less in MDS neutrophils than controls (delta MFI 3467 vs. 4687, p=0.03). In addition, assessment of neutrophil elastase showed that its release from cytoplasmic granules (decreasing MFI for FITC) was diminished in patients with MDS (p=0.00002). On flow cytometry, forward scatter confirmed a significant difference in cell swelling after PMA stimulation (p=0.02). Sideward scatter showed a smaller decrease in granularity after stimulation with H2O2 (p=0.002). The morphological abnormalities did not seem to be attributable to diminished ROS production since measurement of PMA-stimulated ROS production using HE, and assessing oxidative burst activity using DHR did not reveal significant differences. However, H202-stimulated production of HOCl by MPO was lower in MDS patients, albeit only when MPO activity was simultaneously impeded by inhibitors (ABAH and AP). Inhibition of MPO activity was more easily achieved in patients with MDS (p=0.01), corroborating the notion of a partial MPO defect in MDS. Conclusions Our results indicate that NET formation is significantly impaired in MDS neutrophils. Although we found abnormalities of MPO-dependent generation of HOCl, impaired ROS production may not be the only cause of deficient NETosis in MDS. Figure Disclosures Gattermann: Novartis: Honoraria, Research Funding.

Evaluación Económica de Lenalidomida (Revlimid®) Para el Tratamiento Del Síndrome Mielodisplásico Con Deleción 5q de Riesgo Bajo/Intermedio-1

Background Lenalidomide is an effective treatment for patients with lower risk myelodysplastic syndrome (MDS) del5q. It reduces disease-related transfusion requirements, inhibits the malignant clone and causes a delay in tumor growth. There are also benefits in terms of quality of life and use of other health care resources. Objective To perform an economic evaluation of lenalidomide for transfusion-dependent patients with Low/Intermediate-1-risk MDS del 5q from the perspective of the public health care sector in Mexico. Material and methods We developed a cost-effectiveness analysis using a Markov model of 5 stages: MDS transfusion-dependence, MDS transfusion-independence, complications from transfusion, acute myeloid leukemia, and death. The analyzed period was 5 years. Discount rate of 5% after year 1 was applied. Efficacy was elicited from a phase III clinical trial, MDS-004, which shows lenalidomide benefit in patients achieving transfusion-independence. There were also benefits with lenalidomide related to extended overall survival and decreased risk of acute myeloid leukemia. Unitary cost are from public price list of IMSS, and resources use was calculated from a Delphi panel methodology with clinical hematologists. A multivariate sensitivity analysis using a Monte Carlo technique was performed. Results Over a 5-year period, each patient on lenalidomide avoided 487 days of transfusion, on average. The incremental cost per life-year without transfusion dependence is USD$14,072 (Exchange Rate = 1USD = 17.55 MXN). According to the sensitivity analysis the model is robust. If all expected patients are treated, their cost would be wUSD$19.7 million, which represents 0.18% of the total budget in the public health sector. Conclusions Lenalidomide provides important clinical benefits in the treatment of patients with lower risk myelodysplastic syndromes with del5q, with a limited economic impact and with a cost per life living without blood transfusions is within 3 times of the Mexican GDP (Gross Domestic Product).

Age-related inflammatory bone marrow microenvironment induces ineffective erythropoiesis mimicking del(5q) MDS

Anemia is characteristic of myelodysplastic syndromes (MDS). The mechanisms of anemia in MDS are unclear. Using a mouse genetic approach, here we show that dual deficiency of mDia1 and miR-146a, encoded on chromosome 5q and commonly deleted in MDS (del(5q) MDS), causes an age-related anemia and ineffective erythropoiesis mimicking human MDS. We demonstrate that the ageing bone marrow microenvironment is important for the development of ineffective erythropoiesis in these mice. Damage-associated molecular pattern molecules (DAMPs), whose levels increase in ageing bone marrow, induced TNFα and IL-6 upregulation in myeloid-derived suppressor cells (MDSCs) in mDia1/miR-146a double knockout mice. Mechanistically, we reveal that pathologic levels of TNFα and IL-6 inhibit erythroid colony formation and differentially affect terminal erythropoiesis through reactive oxygen species-induced caspase-3 activation and apoptosis. Treatment of the mDia1/miR-146a double knockout mice with all-trans retinoic acid, which promoted the differentiation of MDSCs and ameliorated the inflammatory bone marrow microenvironment, significantly rescued anemia and ineffective erythropoiesis. Our study underscores the dual roles of the ageing microenvironment and genetic abnormalities in the pathogenesis of ineffective erythropoiesis in del(5q) MDS.

New proposals of the WHO working group (2016) for the diagnosis of myelodysplastic syndromes (MDS): Characteristics of refined MDS types

Based on centrally diagnosed 3528 patients in the Düsseldorf registry, we validated the new proposals for the classification of the MDS by the WHO working group: 256 patients were diagnosed as MDSSLD (7,3%), 978 MDSMLD (27,7%), 227 MDS RS SLD (6,4%); 321 MDS RS MLD (9,1%), 159 MDS del(5q) (4,5%), 481 MDSEB 1 (13,6%), 620 MDSEB 2 (17,6%), and 148 MDS-U (4,2%). 352 patients (16,9% of the non blastic types) changed the category, mainly moving from RCMD to MDS RS MLD, RCUD and RCMD to MDS del(5q). Median survival times of the refined groups differed from more than 60 months in the MDSSLD (RS) groups, 37 months in the MDSMLD (RS) groups, 79 months of the MDS del(5q) group and 21 and 11 months in the MDSEB 1 and 2 groups, respectively. The difference between the groups with regard to the risk of AML evolution was also impressing. No major changes were made with regard to the MDS-U categories. In summary, the proposals of the WHO group for the classification of MDS are thoughtful, taking into account biologic parameters of the diseases, a more precise wording, to some extend pragmatic and feasible.

Subsequent primary malignancies and acute myelogenous leukemia transformation among myelodysplastic syndrome patients treated with or without lenalidomide.

The few studies that have examined rates of acute myeloid leukemia (AML) transformation in lenalidomide‐treated myelodysplastic syndrome (MDS) patients have been limited to deletion 5q MDS. The association between lenalidomide and subsequent primary malignancies (SPMs) in MDS patients has not been evaluated previously. We conducted a retrospective cohort study to evaluate the risk of both SPM and AML in association with lenalidomide. A cohort of MDS patients (n = 1248) treated between 2004 and 2012 at Moffitt Cancer Center were identified, and incident cases of SPM and AML transformation were ascertained. Using a nested case–control design, MDS controls were 1:1 matched to SPM (n = 41) and AML (n = 150) cases, on age and date of MDS diagnosis, gender, follow‐up time, IPSS, and del (5q). Associations between lenalidomide and (1) SPM incidence and (2) AML transformation were estimated with hazards ratios (HR) and 95% confidence intervals (CIs) in the cohort and odds ratios (OR) in the case–control analysis. SPM incidence did not differ significantly between cohort MDS patients treated with (0.7 per 100 person‐years) or without lenalidomide (1.4 per 100 person‐years) (HR = 1.04, 95% CI = 0.40–2.74), whereas a significantly reduced SPM risk was observed in the case–control sample (OR = 0.03, 95% CI = <0.01–0.63). Lenalidomide was not associated with AML transformation in the cohort analysis (HR = 0.75, 95% CI = 0.44–1.27) or in the case–control analyses (OR = 1.16, 95% CI = 0.52–2.56), after adjustment for potential confounders. Lenalidomide was not associated with increased risk of SPM or AML transformation in a large cohort of MDS patients mostly including nondeletion 5q MDS.

Application of a Short Tandem Repeat Based PCR Assay for Chronological Monitoring of Myelodysplastic Syndrome (MDS) Patients with Deletion of Chromosome 5q Following Lenalidomide Treatment

IntroductionDeletion of chromosome 5q (del(5q)) defines a distinct clinical subtype of myelodysplastic syndromes (MDS) and qualifies patients to specific treatment with Lenalidomide (LEN). Therefore, detection and monitoring of this deletion is an important element in routine clinical diagnostics for determining molecular response. Current methodologies for performing these analyses consist of cytogenetics, fluorescence in situ hybridization (FISH) or microarrays. All of these methods have downsides due to the high demands to the input material, i.e. viable cells or necessity for large amounts of high quality genomic DNA (gDNA). To perform quantitative assessment of cytogenetic lesions in low quantity or residual material we here present the establishment of a PCR-based assay for interrogation of del(5q) in MDS, based on the allelic loss at heterozygous short tandem repeat (STR) loci within deleted regions.MethodsGenomic DNA was isolated from bone marrow (BM) and peripheral blood (PB) of n=86 MDS del(5q) patients. 49 non-del(5q) MDS patients were used as controls. Serial chronological BM samples (n=95) following treatment with LEN from n=40 del(5q) patients, who were enrolled in the LEMON-5 trial from the German MDS study group, were analysed. Using 10ng DNA, 12 fluorochrome-labelled PCR amplicons of STR loci located between chromosomal bands 5q21 and 5q31 were amplified in a single optimized multiplex-PCR reaction. Subsequently, amplicon fragment analysis was carried out via capillary electrophoresis and allele size quantification of heterozygous STR loci was performed. Finally, the degree of skewing in the allelic ratios of all informative STR markers was averaged and translated into an allelic burden of del(5q).ResultsPaired quantitative correlation of clone sizes using STR-PCR and interphase FISH was carried out in n=34 samples and revealed highly concordant results with r²=0.924. The diagnostic accuracy of the PCR assay was evaluated by receiver operating characteristic (ROC) analysis and revealed an area under the curve of 0.989 (sensitivity and specificity of 0.977 and 0.948, respectively). Prior to treatment with LEN, clone sizes as determined by STR-PCR were heterogeneous (mean: 57%, range: 11-91%). During follow-up analysis, while cytogenetic analyses failed (e.g. metaphase failure) in 7/40 (18%) cases, our STR-PCR assay successfully generated estimates of del(5q) cell burden in all available samples. Upon LEN treatment, n=12 patients achieved major cytogenetic remission (absence of del(5q)-positive metaphases). The mean clone size carrying del(5q) determined by STR-PCR in that group was 7% (range 3 - 10%) and significantly increased compared with n=15 patients who reached minor cytogenetic response (defined as 50% reduced aberrant metaphases, mean 13%, range 5 - 39%, p=0.025). Intriguingly none of n=6 patients without cytogenetic response achieved a del(5q) clone size of less than 35% as determined by STR-PCR (mean 46%, range 35 - 66%), highlighting the correlation of PCR based follow-up analysis with currently used cytogenetic methods for response evaluation. Finally in n=93 matched PB and BM samples a correlation of del(5q)-frequency in BM versus PB showed r²=0.81. Moreover, in 96% of samples in which the BM still showed clone sizes >10%, we reliably detected del(5q) in corresponding PB cells with a robust sensitivity of 5% deleted cells.DiscussionWe present a highly adaptable tool for precise measurement of large chromosomal deletions, requiring only minute amounts of genomic DNA. It shows a very good quantitative correlation with established methods and good diagnostic accuracy. Most importantly, this PCR based assay does not require dividing cells so it can be performed from PB, which shows a sufficient correlation with clone sizes in BM and rarely involves the risk of underrepresentation of del(5q)-clones in PB, possibly allowing the use of PB as a regular specimen for clone size monitoring. Thus, especially in the context of serially monitored patients this assay represents an alternative method for less invasive tracking of cytogenetically aberrant clones. DisclosuresPlatzbecker:Celgene: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Boehringer: Research Funding. Schlenk:Janssen: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Research Funding; Boehringer-Ingelheim: Honoraria; Teva: Honoraria, Research Funding; Arog: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees. Bug:TEVA Oncology, Astellas: Other: Travel Grant; NordMedica, Boehringer Ingelheim, Gilead: Membership on an entity's Board of Directors or advisory committees; Celgene, Novartis: Research Funding. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

In patients with myelodysplastic syndromes with del(5q), factors other than age and sex contribute to the prognostic advantage, which diminishes over time.

This study aimed to determine the extent to which the prognostic advantage of myelodysplastic syndromes (MDS) with del(5q) is due to the more favourable age and sex distribution of patients in that group when compared to other MDS subtypes. A total of 1912 MDS patients from the Duesseldorf registry with less than 5% blasts in the bone marrow were evaluable and had complete covariates. As endpoints, overall survival and progression to acute myeloid leukaemia (AML) were considered. Cox models were computed for both outcomes. A multivariate Cox model for survival confirmed higher age and male sex as risk factors. In addition, we found a survival advantage of 9·1years for MDS del(5q) patients compared to refractory cytopenia with unilineage dysplasia, while the survival advantage of MDS del(5q) over refractory cytopenia with multilineage dysplasia was 18·6years. Considering progression to AML, we did not find any significant differences between the World Health Organization classification subtypes. Our analyses show that the higher survival probabilities of MDS del(5q) patients are not only due to age and sex, although higher age and male sex were also important risk factors. Interestingly, it seems that the survival advantage of MDS del(5q) decreases over time.

Lenalidomide and Risk of Acute Myeloid Leukemia (AML) Transformation Among Myelodysplastic Syndrome (MDS) Patients

Introduction: Lenalidomide is currently approved by the FDA for treatment of transfusion-dependent, lower risk, deletion 5q (del(5q)) MDS patients. In practice, lenalidomide is often used for treatment of non-del(5q) anemic, lower risk MDS patients as endorsed by national guidelines. The risk of AML transformation among non-del(5q) MDS patients treated with lenalidomide has not been well studied, nor among del(5q) MDS patients outside the context of original clinical trials. We conducted a retrospective cohort study of 1,248 MDS patients treated with or without lenalidomide at the Moffitt Cancer Center (MCC) to investigate the association between lenalidomide and AML transformation.Methods: Patients treated for MDS at MCC in 2004-2012 were identified through MCC’s data warehouse, including data from the Cancer Registry, electronic medical records and disease-specific databases. A total of 1,248 MDS patients, ages 18+ years, were identified, corresponding to International Classification of Diseases for Oncology Third Edition (ICD-O-3) codes 99801, 99803, 99833, 99843, 99853, 99863, 99873, 99891 and 99893. A total of 150 cases of AML transformation were verified by two hematologists confirming the MDS diagnosis and AML transformation. Incidence rates and 95% confidence intervals (CI) for AML transformation were estimated based on the Poisson distribution. Cox proportional hazards ratios (HR) and 95% CIs were calculated to estimate age-adjusted associations between lenalidomide treatment and AML transformation in the overall cohort, and stratified by lower (low and intermediate-1) risk versus higher (intermediate-2 and high) risk IPSS. To obtain additional details on lenalidomide treatment and potential confounders, medical chart abstraction was conducted for all AML cases and a sample of MDS patients from the baseline cohort who had not developed AML; these controls were matched to cases 1:1 on age at MDS diagnosis (<60 versus 60+ years), gender, follow-up time (+/- 6 months), date of diagnosis, (+/- 1 year), lower versus higher risk IPSS, and presence or absence of del (5q). Based on the abstracted data for the nested case-control sample, associations between lenalidomide and AML transformation were adjusted for cytogenetic risk, use of erythroid-stimulating agents (ESA), percent bone marrow myeloblasts, and MDS histology.Results: Overall, 1,248 MDS patients were followed for an average of 30 months, including patients treated with (n=210) or without (n=1,038) lenalidomide. AML transformation was observed among 16 patients treated with lenalidomide (2.4 per 100 person-years) and 134 patients treated without lenalidomide (5.5 per 100 person-years), corresponding to an age-adjusted HR of 0.44 (95% CI=0.26-0.74). Only two of the 150 MDS patients who transformed to AML had MDS del(5q). When stratified by IPSS, there was no increased risk of AML transformation associated with lenalidomide among patients with lower risk IPSS (HR=0.27, 95% CI=0.12-0.64) or patients with higher risk IPSS (HR=0.99, 95% CI=0.51-1.93). Based on the nested case-control analysis, 16.0% and 20.7% of MDS-AML cases and matched MDS controls who did not develop AML were treated with lenalidomide, respectively, corresponding to an adjusted odds ratio (OR) of 1.16 (95% CI=0.52-2.56). Although a significant interaction was noted between lenalidomide and IPSS in relation to AML in the cohort analysis (Figure 1), lenalidomide was not associated with AML transformation among lower risk (OR=0.44, 95% CI=0.10-1.94) or higher risk (OR=2.06, 95% CI=0.69-6.18) MDS patients after adjustment for prognostic factors in the case-control analysis.Conclusion: To our knowledge, this study represents the largest cohort investigated outside the context of clinical trials for the rate of AML transformation among MDS patients treated with lenalidomide and the first to specifically examine non-del(5q) patients. Lenalidomide treatment was not associated with an increased risk of AML transformation among this large cohort of MDS patients. [Display omitted] DisclosuresRollison:Celgene, Inc.: Research Funding. Off Label Use: Lenalidomide given as treatment for non-del(5q) MDS and/or multiple myeloma . Shain:L&M Healthcare/Onyx/Amgen: Research Funding, Speakers Bureau; Envision/Celgene: Research Funding, Speakers Bureau. Lee:Celgene, Inc.: Research Funding. Hampras:Celgene, Inc: Research Funding. Fulp:Celgene, Inc.: Research Funding. Fisher:Celgene, Inc: Research Funding. Al Ali:Celgene, Inc: Research Funding. Padron:Icyte: Speakers Bureau; Novartis: Speakers Bureau. Lancet:Celgene, Inc: Consultancy, Research Funding. Xu:Celgene, Inc.: Employment, stock options Other. Knight:Celgene, Inc: Employment, stock options Other. List:Celgene, Inc.: Consultancy. Dalton:Genentech: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene, Inc.: Research Funding. Komrokji:Celgene: Consultancy, Research Funding.

Differences In Treatment and Diagnostic Patterns In Private Vs Public Sectors For Deletion 5Q Myelodysplastic Syndromes (MDS) In Mexico: Results From A Physician Survey

ObjectiveDeletion of the long arm of chromosome 5 (5q) is the most common chromosomal abnormality seen in MDS; however, there is little information about treatment and diagnostic patterns, especially in Latin America. This study aimed to understand the real-life approach to diagnosis and treatment of MDS del(5q) in Mexico in 2012. MethodsOverall clinical practice was investigated through a physician face-to-face survey. Eligible participants were 10 hematologists and/or hemato-oncologists with at least 5 years experience treating patients with MDS and practicing in one of 5 major public hospitals in Mexico City (IMSS, ISSSTE or MoH) and/or two private hospitals (Español and Angeles Lomas). The interview covered 6 sections: (1) physician´s point of view about the disease and MDS and/or del(5q) patient profile; (2) diagnosis; (3) treatment patterns, including country-specific barriers for each; (4) patient access to appropriate drug treatment, (5) knowledge and perception about innovative drugs such as lenalidomide; and (6) areas of opportunity in diagnosis and/or treatment. ResultsPhysicians described patient flow for most in the public sector as starting at Family Medicine Units and second level hospitals, which tend to basic health issues; eventually most are referred to a hematologist in third-level high-specialty hospitals. In private practice about 60% first contact a general physician and all eventually get referred to a specialist; the other 40% go directly to a hematologist. Furthermore, ∼80% who start treatment in the private setting eventually switch to public healthcare since MDS treatment is for life and cost is of great concern. Even though interviewed physicians have a clear sense about MDS diagnosis, they all agree that there is a lack of information about the disease within the medical community, which complicates even further the diagnosis and early patient referral. Eight out of 10 doctors recognized del(5q) as a low-risk disease; the rest considered it as having rapid progression to leukemia, which is a misconception. In practice, 9 out of 10 said MDS is usually diagnosed by exclusion; however, all agreed that del(5q) abnormality diagnosis needs to be identified through karyotyping. All physicians agree that most patients seek medical attention due to fatigue and constant bleeding and receive treatment for anemia prior to reaching a specialist; however, in the public sector they tend to arrive in a more advanced disease stage. Research indicated that the tests to detect MDS are fully covered by the public health system, however, not for detecting del(5q) subtype. In the public sector CBC or blood smear (US$20-30 out-of-pocket) and bone marrow aspiration or biopsy are free of charge (US$300-400 out-of-pocket). Conversely, karyotyping for MDS is only covered by the second largest provider (ISSSTE, covering 9% of the population) and FISH testing is rarely done overall; however, for both, most of the time they are paid out-of-pocket (US$200-500).Treatment preferences and duration vary greatly, mainly because of drug availability, physician disease expertise and patients' willingness to pay out-of-pocket for appropriate testing/drugs. Physicians acknowledge lenalidomide as the best treatment option for del(5q) MDS (some are already using lenalidomide for myeloma); however, due to its high cost and restricted availability in the public sector, they use whatever is readily available. Thalidomide is usually used in 1st line treatment, cyclosporine and prednisone as 2nd line and hypomethylating drugs, such as azacitadine, or bone marrow transplant as 3rd line. Additionally, due to misdiagnosis and/or co-morbidities, patients are treated with erythropoietin (anemia), GCSF (leucopenia), platelet agonists (thrombocytopenia), and iron chelators (iron excess due to transfusions). ConclusionMost physicians conclude that in order to have appropriate del(5q) MDS diagnosis and treatment there is a clear opportunity to increase continuous medical education on the disease as well as training to spur more highly qualified geneticists. Moreover, there is a need to have more reference centers and genetic testing laboratories and greater availability of del(5q) karyotype testing in the public sector. Finally, results from this research indicates that improving access to novel drugs, such as lenalidomide, will expand the treatment options available for del(5q) MDS in Mexico. Disclosures:No relevant conflicts of interest to declare.

Early Lenalidomide Maintenance to Prevent Relapse of High-Risk MDS and AML Patients with Del(5q) Following Allogeneic HCT - Results of the “LENAMAINT” Trial

Abstract 3060 Background:Chromosome 5 abnormalities in patients (pts) with acute myeloid leukemia (AML) or advanced myelodysplastic syndrome (MDS) are mostly associated with a poor outcome. Although allogeneic hematopoietic stem cell transplantation (HCT) is the treatment approach with the highest curative potential, early relapse rates following HCT are still considerably high. Since therapeutic options in these pts are often limited, the prevention of relapse represents a major challenge. Lenalidomide (LEN) has been successfully used in MDS pts with del(5q) cytogenetic abnormalities. Besides a direct anti-proliferative effect on del(5q) progenitors, its immunmodulatory function might also enhance T-or NK cell mediated GVL effects. Therefore it could be an effective maintenance drug to prevent relapse after allogeneic HCT in pts with MDS or AML and del(5q) abnormalities. Methods:We report results of a prospective multicenter phase II clinical trial evaluating the efficacy to prevent relapse as well as safety of LEN maintenance following HCT in pts with MDS or AML and cytogenetic abnormalities including del(5q). Only pts achieving a complete hematological remission (CR) after HCT were eligible. In the absence of toxicity or relapse pts could receive up to 12 cycles of LEN maintenance at a dose of 10 mg/day orally, for 21 days, with 7 days rest (28 day cycle). Results:Ten pts with either MDS (n=1, RAEB-1) or AML (n=9) with a median age of 65 years (range 40–72) were included. The disease status prior to allogeneic HCT were CR in 4 pts, relapse/refractory disease in 3 pts, unknown in 2 pts while the MDS pt had not received any prior therapy. A complex aberrant karyotype including del(5q) was documented in 5 pts. Two pts had an additional cytogenetic abnormality besides del(5q) and 3 pts displayed single del(5q). While three pts underwent allogeneic HCT from a matched sibling donor, four pts were transplanted from a matched unrelated and three from a mismatched unrelated donor (single allele or antigen mismatch). Conditioning was of reduced intensity and was followed by the infusion of peripheral blood stem cells in all pts. LEN maintenance therapy was started after complete hematopoietic recovery with documented complete remission at a median of 2.5 months (range 2–4 months) following HCT. After a median of 4 cycles 8 of 10 pts (80%) had to discontinue LEN treatment due to relapse (n=4), development of severe GvHD grade 2–4 (n=2) or other adverse events (n=2). Altogether, 6 of 10 pts (60%) developed severe acute GvHD grade 3–4 within the first 2 cycles of LEN maintenance. All pts were still under systemic immunosuppression at the time of GvHD appearance. Other common adverse events were gastrointestinal side effects (nausea) and myelotoxicity. Reversible neutropenia grade 3/4 was documented in 3 of 10 (30%) of the pts while thrombocytopenia grade 3/4 occurred in 4 of 10 (40%) of them. During the treatment course specific T cell responses against different tumor/leukemia-associated antigens (TAAs/LAAs) using ELISpot analysis for Interferon alpha and granzyme B were measured. Sufficient T cells before and during LEN treatment were only available in one pt, who showed an increase of specific T cell responses against the TAAs/LAAs. With a median follow-up of 254 days (range 32–677) from the start of LEN maintenance, 5 of 10 pts (50%) are currently alive with four pts in continuous CR since the time of HCT. The study was stopped prematurely because of suspected induction of GVHD by LEN. Conclusions:Early LEN maintenance to prevent relapse following HCT in pts with MDS or AML and del(5q) may be associated with the induction of severe acute GVHD. Disclosures:Kobbe:Celgene: Consultancy, Research Funding; Ortho Biotec: Consultancy. Germing:Celgene: Consultancy, Research Funding. Bornhaeuser:Celgene: Honoraria. Platzbecker:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Pulmonary Hypertension May Be a Relevant Comorbidity in Patients with Myelodysplastic Syndromes

Abstract 5039 Background:Pulmonary hypertension (PH) is characterized by elevated pulmonary arterial pressure and increased pulmonary vascular resistance, leading to right-sided heart failure and death. PH is defined as an increase in mean pulmonary arterial pressure (mPAP) ≥25 mmHg at rest. PAP values can be non-invasively estimated by Doppler echocardiography while right heart catheterization is needed for definite diagnosis. Hematologic disorders are associated with PH but it is unknown if myelodysplastic syndromes (MDS) bear an increased risk for PH. The objective of this study was to investigate the prevalence of PH in patients with MDS. Patients and Methods:From March 2009 to July 2011 consecutive MDS patients were recruited from the Hematology Division of the Medical University of Graz and enrolled in this PH screening program. All patients underwent Doppler echocardiography. PH was suspected if resting systolic pulmonary arterial pressure (SPAP) exceeded 40 mmHg.Additionally six minute walk distance (6MWD), pulmonary function test (PFT), laboratory tests including N-terminal pro brain natriuretic peptide (NT-proBNP), IPSS Score and WHO functional class were determined. Results:Fourty four MDS patients (female:male=18:26, age 70±12 years, disease onset 5±8 years, NYHA functional class I:II:III:IV=21:16:7:0, IPSS low/intermediate-I/intermediate- II/high/unknown=16:14:8:3:3; hemoglobin: 11±2 g/dl, white blood cell count 4±3 g/l; platelet count 159±125 g/l; regular transfusions n=19; WHO Classification: RCUD/RARS/RCMD/MDS del(5q)/RAEBI/RAEB II/MDSU=2:3:21:2:6:6:4 ) were included.Six patients had elevated SPAP (PH group, SPAP: 56±9mmHg) vs. 38 patients with normal values (SPAP 29±5mmHg). PH group were slightly older (79±9 vs. 69±11 years, p=0.53), had a decreased right ventricular function (TAPSE: 18±5mm vs. 22±4mm, p=0.05), a larger left atrium (46±5mm vs. 36±9mm measured in the parasternal long axis, p=0.005), a slightly decreased left ventricular systolic function (fractional shortening: 30±11% vs. 38±9 %, p=0.1) a significantly lower 6MWD (275±117m vs. 438±105m, p=0.01) and higher NT proBNP (4515±4732 pg/ml vs. 313±252 pg/ml, p=0.001) than patients with normal SPAP. In 4/6 PH group patients a relevant diastolic dysfunction of the left ventricle was suggested by echocardiography. Conclusion:According to our data, PH is present in about 15% of MDS patients and is associated with decreased physical capacity and heart failure. This suggests that PH may be considered as a relevant comorbidity in this cohort of patients. The reason of PAP increase may be multifactorial, postcapillary factors probably playing a relevant role. Disclosures:No relevant conflicts of interest to declare.

Initial Clinical Findings From a Population-Based Study of Adult Myelodysplastic Syndrome: Discordance Between World Health Organization (WHO) Classifications

Abstract 1733 Introduction:Much remains to be elucidated regarding the etiology of myelodysplastic syndrome (MDS) and why some cases progress to acute myeloid leukemia. Further, there are few data on how accurate case classification is within state cancer registries and the impact of the 2008 WHO MDS classification modifications on clinical practice. We are conducting a large population-based prospective study of MDS to investigate risk factors for initial disease as well as disease progression. Our study includes comprehensive central review of all cases. Initial findings are reported here. Methods:We began evaluation and follow-up of all newly diagnosed MDS cases in Minnesota between the ages of 20 and 85 years from April 1, 2010 onward. Our process includes rapid case identification by the Minnesota Cancer Surveillance System (MCSS), contact of individual patients after primary physician approval, and, for interested patients, participation in an extensive questionnaire with medical history review and optional saliva sample for DNA. In concert, all cases pass through central medical review including: 1) independent pathology report +/− slide review by two hematopathologists to confirm diagnosis and subclassification; 2) independent cytogenetic review by a cytogeneticist; and 3) medical chart review by an oncologist to identify pertinent clinical history and prospectively calculate the International Prognostic Scoring System (IPSS) and WHO-based prognostic scoring system (WPSS) scores. Annual follow-up is planned to monitor for disease progression and outcome. In cases of unknown cytogenetics, IPSS calculations are not completed. In cases of unknown cytogenetics or diagnosis of MDS-U, not currently stratified in the WPSS, WPSS calculations are not completed. Results:We describe the first 67 patients enrolled on this study that have completed central review. The majority of patients were male (n=44) and the median age of the cohort at diagnosis was 71 (range 41–85). Table 1Table 1:Patient DemographicsVariableTotal (n = 67)Age:41-601161-701571-8541IPSS Risk Category: #Low17Intermediate-121Intermediate-223High5WPSS: *Very Low15Low5Intermediate9High30Very High5Concordance assessment of initial WHO diagnosis determined by MCSS and WHO diagnosis after central review found a total of 21 discordant diagnoses (31.3%). The discordant cases included: 10 cases initially diagnosed as MDS-U that central review further delineated into RA (1), RT(1), RARS (1), RCMD (3), RAEB (2), and therapy related MDS (2); 1 case originally classified as RA to MDS-U; 6 cases transitioned from RAEB to t-MDS (5) and RCMD (1); and 4 cases initially described as RCMD changed to MDS del 5q (1), RAEB (2), t-MDS (1). Table 2#IPSS not calculable in 1 case due to missing cytogenetics*WPSS not calculable in 3 cases due to MDS-U (2) and no cytogenetics (1)Table 2:Comparison of WHO ClassificationWHO Classification per MCSSWHO Classification after Central ReviewRefractory Anemia (RA)22Refractory Thrombocytopenia (RT)1Refractory Anemia with Ringed Sideroblasts (RARS)1011Refractory Cytopenias with multilineage dysplasia (RCMD)1414Refractory Anemia with Excess Blasts (RAEB):–RAEB-1299–RAEB-218MDS with deletion 5q12MDS-Unclassifiable (MDS-U)112Therapy related MDS (t-MDS)8 Conclusion:Ours is the first large prospective population-based study of MDS that includes central pathology, cytogenetic, and clinical review of newly diagnosed patients with prospective calculation of IPSS and WPSS and plans for long term follow-up. This study is expected to enroll approximately 700 MDS cases over a five year period. While early in investigation, our initial review highlights the variability in distinct WHO diagnosis between initial cancer registry (i.e., MCSS) designation and designation after thorough central review of all appropriate diagnostic components. Our data suggest the robustness of the WHO RA, RARS, and RCMD classifications, the possible over-utilization of MDS-U classification, and highlight the under-representation of therapy-related MDS identification with registry designation. The impact of discordant diagnoses between MCSS and central review on therapeutic strategies is uncertain, but warrants continued evaluation and underscores the importance of complete central review in evaluation of MDS cases. Supported by NIH R01 CA142714. Disclosures:No relevant conflicts of interest to declare.

Results of a Multicenter Treatment Survey Yielding Insights Into Diagnosis and Management of MDS Patients In Daily Clinical Practice In Germany

AbstractAbstract 4959During the last few years (yrs) remarkable improvements have been made in the treatment of patients (pts) with myelodysplastic syndromes (MDS). However, there are only few analyses available on daily clinical practice, in particular on how pts are managed in the era of hypomethylating agents. For the first time, this analysis offers a comprehensive insight into diagnosis and management of MDS in Germany. Prior to patient documentation, 117 of 886 centers contacted provided information on patient load in a structural evaluation; the data collection period was scheduled accordingly. The data for this retrospective, non-interventional analysis were gathered during the 3rd and 4th quarter of 2009. 57 representative institutions documented 303 pts (41% from private-based offices [PBO], 59% from hospitals), 269 of which met the inclusion criteria (treatment decision, i.e. start, change or discontinuation, during data collection period; pts fully documented; positive plausibility check of data) of this analysis. Median age at the time of first diagnosis was 70 yrs. 78% had a Karnofsky Index (KI) ≥ 80%. The most common symptoms leading to diagnosis included cytopenia (e.g. anemia 79%), fatigue (38%), and deteriorating performance (36%). Distribution among MDS types according to the FAB classification at the time of first diagnosis was: 32% RA, 16% RARS, 20% RAEB, 4% RAEB-T, 7% CMML (21% “not documented”). According to WHO classification (2008), the distribution was: 17% RCUD, 12% RARS, 23% RCMD, 13% RAEB-I, 15% RAEB-II, 1% MDS-U, 5% MDS with del5q, 14% unknown/not classified as MDS. Cytogenetic analysis was performed in 67% of pts at initial diagnosis, but much less frequently (44%) in pts > 75 yrs (p<0.001; see table). The proportion of pts karyotyped was higher in university hospitals (83%) than non-university hospitals (63%) and PBOs (58%). Accordingly, more pts had their prognosis assessed by IPSS in university hospitals (75%) than non-university hospitals (61%) and PBOs (48%) (p=0.01). Red blood cell transfusions (RBCT) were given more often in non-university hospitals (30%) than university hospitals (10%) or PBOs (23%) prior to first diagnosis. The percentage of pts receiving RBCT was lower among older pts (> 70 yrs). However, length of transfusion history and frequency of RBCT were higher in older pts. The IPSS score was calculated in 61% of all pts at diagnosis. IPSS score calculation depended on several factors, e.g. RBCT dependence prior to diagnosis, age, and WHO MDS type. On bivariate analysis, IPSS scoring at first diagnosis was done significantly less frequently in pts > 75yrs (p=0.014; see table) and significantly more frequently in pts belonging to WHO types RCUD, MDS del(5q) and RAEB I-II (p<0.001). The IPSS score was more regularly used in university hospitals than other institutions (p=0.001). On multivariate analysis, the WHO type of MDS was confirmed to be the most relevant predictor of physicians using the IPSS (p<0.001). When trying to identify factors driving active treatment (defined as chemotherapy, stem cell transplantation (SCT), immunosuppressants, hypomethylating or other novel agents) in this survey, bivariate analysis showed a significant correlation with age ≤ 75 yrs (p=0.007) and the WHO types of RCUD, MDS del(5q), and RAEB I-II (p=0.0019); multivariate analysis revealed age as the most important factor (p=0.006; see table). MDS initial treatment was as follows: Supportive care only (34%), G-CSF/ESA only (16%), azacitidine (19%), any other active treatment (27%), and allogeneic SCT (5%). Azacitidine was the active treatment most frequently used (44 % overall) in MDS pts.Table:Impact of age on MDS diagnosis and treatmentPts ≤ 75yrsPts >75yrsSignificance% of pts with cytogenetic analysis performed at first diagnosis72.9%43.7%p<0.001% of pts with assessment of IPSS score65.4%51.0%p=0.014% of pts receiving active treatment39.7%22.2%p=0.006 Conclusion:While distribution among prognostic groups in this survey was consistent with previous findings from the Duesseldorf MDS Registry, it became clear that many patients, particularly the older ones, did not receive a comprehensive risk assessment including cytogenetics/IPSS. Proper risk assessment, however, is important for correct and consistent therapeutic decision-making, particularly with the availability of treatment options that offer a significant survival benefit to defined groups of patients. Disclosures:Gattermann: Novartis, Celgene: Honoraria, Research Funding. Kuendgen: Celgene: Honoraria. Zeffel: Celgene: Employment. Berger: Celgene: Employment. Germing: Celgene, Chugai, Novartis, Amgen: Honoraria; Celgene, Novartis, Amgen, GSK: Research Funding.