Somatic mutations predict poor outcome in patients with myelodysplastic syndrome after hematopoietic stem-cell transplantation

Immune checkpoints bone marrow expression as the predictor of clinical outcome in myelodysplastic syndrome

Aims

In our single-center retrospective study we evaluated whether level of different checkpoint molecules in bone marrow biopsies at diagnosis affect the clinical course of patients with myelodysplastic syndrome (MDS).

Methods and results

A consecutive cohort of 55 MDS patients treated in our center from 2003 to 2018 with available bone marrow biopsies at time of diagnosis was studied. We used a technique able to detect the expression of the following antigens: PD-1, PD-L1, PD-L2, LAG-3, Gal-9, TIM-3, CD80. The association between expression level and 3-year overall and relapse-free survival and time-to-progression was analyzed. Intensive expression of TIM-3 was observed in 100% of cases. Also, in most cases, moderate Gal-9 expression was observed. With 3-year follow-up disease progression was seen in 72.9% of patients with high CD80 level and 52.1% of patients with low CD80 level (p=0.04). PD-1, CTLA4 and TIM-3 ligands were co-expressed in the majority of patients. General checkpoint ligand expression level also was associated with increased 3-year incidence of progression: 67.2% of patients with high level of checkpoint ligands progressed, while in the group with low checkpoint ligand expression level progression was observed only in 33.3% of cases (p=0.059). There was an association between the expression of checkpoint molecules CD80, PD-L2, TIM3, the number of bone marrow blasts and risk according to IPSS and IPSS-R scales.

Conclusions

Our preliminary study underlined heterogeneous immune checkpoint molecules expression in MDS and warrants further studies to define the role of this heterogeneity and develop optimal treatment approaches.

Epigenetic priming with decitabine followed by low dose idarubicin and cytarabine in acute myeloid leukemia evolving from myelodysplastic syndromes and higher-risk myelodysplastic syndromes: a prospective multicenter single-arm trial

Patients with acute myeloid leukemia (AML) evolving from myelodysplastic syndrome (MDS) or higher-risk MDS have limited treatment options and poor prognosis. Our previous single-center study of decitabine followed by low dose idarubicin and cytarabine (D-IA) in patients with myeloid neoplasms showed promising primary results. We therefore conducted a multicenter study of D-IA regimen in AML evolving from MDS and higher-risk MDS. Patients with AML evolving from MDS or refractory anemia with excess blasts type 2 (RAEB-2) (based on the 2008 WHO classification) were included. The D-IA regimen (decitabine, 20 mg/m² daily, days 1 to 3; idarubicin, 6 mg/m² daily, days 4 to 6; cytarabine 25 mg/m² every 12 hours, days 4 to 8; granulocyte colony stimulating factor [G-CSF], 5 μg/kg, from day 4 until neutrophil count increased to 1.0 × 10⁹ /L) was administered as induction chemotherapy. Seventy-one patients were enrolled and treated, among whom 44 (62.0%) had AML evolving from MDS and 27 (38.0%) had RAEB-2. Twenty-eight (63.6%) AML patients achieved complete remission (CR) or complete remission with incomplete blood count recovery (CRi): 14 (31.8%) patients had CR and 14 (31.8%) had CRi. Six (22.2%) MDS patients had CR and 15 (55.6%) had marrow complete remission. The median overall survival (OS) was 22.4 months for the entire group, with a median OS of 24.2 months for AML and 20.0 months for MDS subgroup. No early death occurred. In conclusion, the D-IA regimen was effective and well tolerated, representing an alternative option for patients with AML evolving from MDS or MDS subtype RAEB-2.

Myelodysplastic syndromes: a review of therapeutic progress over the past 10 years

INTRODUCTION

Myelodysplastic syndromes (MDS) represent a range of bone marrow disorders, with patients affected by cytopenias and risk of progression to AML. There are limited therapeutic options available for patients, including hypomethylating agents (azacitidine/decitabine), growth factor support, lenalidomide, and allogeneic stem cell transplant.

AREAS COVERED

This review provides an overview of the progress made over the past decade for emerging therapies for lower- and higher-risk MDS (MDS-HR). We also cover advances in prognostication, supportive care, and use of allogeneic SCT in MDS.

EXPERT OPINION

While there have been no FDA-approved therapies for MDS in the past decade, we anticipate the approval of luspatercept based on results from the MEDALIST trial for patients with lower-risk MDS (MDS-LR) and ringed sideroblasts who have failed or are ineligible for erythropoiesis stimulating agents (ESAs). With growing knowledge of the biologic and molecular mechanisms underlying MDS, it is anticipated that new therapies will be approved in the coming years.

Following in the footsteps of acute myeloid leukemia: are we witnessing the start of a therapeutic revolution for higher-risk myelodysplastic syndromes?

For most patients with higher-risk myelodysplastic syndromes (HR-MDS) the hypomethylating agents (HMA) azacitidine and decitabine remain the mainstay of therapy. However, the prognosis mostly remains poor and aside from allogeneic hematopoietic stem cell transplantation no curative treatment options exist. Unlike acute myeloid leukemia, which has seen a dramatic expansion of available therapies recently, no new agents have been approved for MDS in the United States since 2006. However, various novel HMAs, HMA in combination with venetoclax, immune checkpoint inhibitors, and targeted therapies for genetically defined patient subgroups such as APR-246 or IDH inhibitors, have shown promising results in early stages of clinical testing. Furthermore, the wider availability of genetic testing is going to allow for a more individualized treatment of MDS patients. Herein, we review the current treatment approach for HR-MDS and discuss recent therapeutic advances and the implications of genetic testing on management of HR-MDS.

TP53 in Myelodysplastic Syndromes: Recent Biological and Clinical Findings

TP53 dysregulation plays a pivotal role in the molecular pathogenesis of myelodysplastic syndromes (MDS), identifying a subgroup of patients with peculiar features. In this review we report the recent biological and clinical findings of TP53-mutated MDS, focusing on the molecular pathways activation and on its impact on the cellular physiology. In MDS, TP53 mutational status is deeply associated with del(5q) syndrome and its dysregulation impacts on cell cycle, DNA repair and apoptosis inducing chromosomal instability and the clonal evolution of disease. TP53 defects influence adversely the MDS clinical outcome and the treatment response rate, thus new therapeutic approaches are being developed for these patients. TP53 allelic state characterization and the mutational burden evaluation can therefore predict prognosis and identify the subgroup of patients eligible for targeted therapy. For these reasons, in the era of precision medicine, the MDS diagnostic workup cannot do without the complete assessment of TP53 mutational profile.

Do next-generation sequencing results drive diagnostic and therapeutic decisions in MDS?

This article has a companion Point by Thol and Platzbecker.

Cui bono? Finding the value of allogeneic stem cell transplantation for lower-risk myelodysplastic syndromes

Introduction: The myelodysplastic syndromes (MDS) vary in their risk of disease progression; progression includes increasingly severe bone marrow failure, reclassification as acute myeloid leukemia (AML), and death. Prognostic tools guide recommendations for allogeneic stem cell transplantation (alloSCT), the only curative option. AlloSCT is typically reserved for patients with higher-risk MDS as defined by existing prognostic tools, although additional clinical and biological factors in lower-risk patients may influence this dogma.Areas covered: This review discusses the current understanding of MDS risk stratification as it pertains to the use of alloSCT in subpopulations of MDS patients with a particular focus on the use of alloSCT in patients with lower-risk disease.Expert commentary: Though high-quality data are lacking, some lower-risk MDS patients may benefit from alloSCT, which offers the only prospect of cure. Understanding the etiologic role and prognostic impact of recurring genetic events may improve existing risk stratification and become integral facets of prognostic schemata. The identification of additional factors influencing the prognoses of patients currently lumped together as 'lower-risk' will likewise improve the selection of MDS patients for early intervention or aggressive therapies such as alloSCT.

Evolving therapies for lower-risk myelodysplastic syndromes

The development in the therapeutic landscape of myelodysplastic syndromes (MDS) has substantially lagged behind other hematologic malignancies with no new drug approvals for MDS for 13 years since the approval of decitabine in the United States in 2006. While therapeutic concepts for MDS patients continue to be primarily defined by clinical-pathologic risk stratification tools such as the International Prognostic Scoring System (IPSS) and its revised version IPSS-R, our understanding of the genetic landscape and the molecular pathogenesis of MDS has greatly evolved over the last decade. It is expected that the therapeutic approach to MDS patients will become increasingly individualized based on prognostic and predictive genetic features and other biomarkers. Herein, we review the current treatment of lower-risk MDS patients and discuss promising agents in advanced clinical testing for the treatment of symptomatic anemia in lower-risk MDS patients such as luspatercept and imetelstat. Lastly, we review the clinical development of new agents and the implications of the wider availability of mutational analysis for the management of individual MDS patients.

Higher-risk myelodysplastic syndromes with del(5q): does the del(5q) matter?

Introduction: Myelodysplastic Syndrome (MDS) represents a group of cancers characterized by abnormal blood cell formation and maturation, leading to various degrees of cytopenias and potential transformation to acute myeloid leukemia. Deletion of the long arm of chromosome 5 (del(5q)) is the most common clonal chromosomal anomaly in MDS, yet the population in this disease subtype is quite heterogeneous. This manuscript analyzes literature on high-risk MDS with del(5q) abnormalities.Areas covered: The paper will review outcomes with lenalidomide among high-risk MDS patients with del(5q). It will discuss the implications of harboring TP53 gene mutations, and share the data for allogeneic hematopoietic stem cell transplantations in this setting. Finally, the report evaluates the risk of disease progression in these patients.Expert commentary: Improved characterization of MDS has enhanced our understanding of patients with anomalies involving del(5q). Emerging literature is exploring combination therapy beyond lenalidomide, and next-generation sequencing may identify secondary mutations that could be an additional avenue for treatment.

Therapeutic targeting of TP53-mutated acute myeloid leukemia by inhibiting HIF-1α with echinomycin

TP53 mutation in acute myeloid leukemia (AML) is associated with poor prognosis. Since no targeted therapy is available to restore p53 function, it is of great interest to test whether other pathways activated by TP53 mutations can be therapeutically targeted. Here we showed HIF-1α target genes are enriched in TP53-mutated vs TP53-wild type AML. To determine the role of this activation, we tested efficacy of HIF-1α inhibitor echinomycin in TP53-mutated AML samples in vitro and in vivo. Echinomycin was broadly effective against a panel of primary AML blast cells, with low nanomolar IC₅₀s and, based on colony-forming unit assay, was 10-fold more effective in eliminating AML stem cells. Echinomycin selectively eliminated CD34⁺CD38^- AML cells. To test the therapeutic efficacy of echinomycin, we established a xenograft model of TP53-mutated AML. Echinomycin was broadly effective against xenografts from multiple AML samples in vivo, and more effective than cytarabine ₊ daunorubicin chemotherapy. Importantly, while cytarabine ₊ daunorubicin enriched for AML stem cells, echinomycin nearly eliminated this population. Using TP53-mutated AML cell line THP1 and patient-derived AML cells, we tested a new echinomycin formulation with longer half-life and significantly improved therapeutic effect. Our data suggest a novel approach to treat AML with TP53 mutations.

TP53 mutations are associated with very complex karyotype and suggest poor prognosis in newly diagnosed myelodysplastic syndrome patients with monosomal karyotype

AIM

The aim of this study was to evaluate the clinical and molecular characteristics of myelodysplastic syndrome (MDS) patients with monosomal karyotype (MK).

METHODS

Eighty MDS patients with MK diagnosed between January 2010 and December 2018 were included in the retrospective study. Seventy-three had complex karyotype (CK) and 46 had very CK (vCK, ≥ 5 abnormalities). Clinical information was collected, and a panel of 37 genes, on which mutations have been previously reported to be associated with MDS patients, was analyzed by next-generation sequencing. Genetic and biological features and their association with survival were evaluated.

RESULTS

Monosomy 5, 7, and 17 were the most frequent and mainly occurred in patients with vCK. While median overall survival (OS) for all patients was 12.8 months with 95% CI 9.1-16.5, patients with vCK had shorter OS (8.4 months with 95% CI 3.9-12.8) than those with non-vCK (16.1 months with 95% CI 11.5-20.8) (P = .02). At least one gene mutation was detected in 76 patients (95%), TP53 mutations were detected in 57 patients, and their median OS was significantly shorter than those without TP53 mutations (9.5 months with 95% CI 7.5-11.5 vs 26.1 months with 95% CI 8.0-44.2, P < .01). In 34 patients who received treatment with decitabine, 25 with TP53 mutations had higher overall response rate than those with wild-type TP53 (60% vs 22.2%, P = .03). However, OS was still significantly shorter in those with TP53 mutations (10.1 vs 26.1 months, P = .03). Multivariate analysis confirmed that TP53 mutations was an independent poor prognostic factor on OS.

CONCLUSIONS

CK and vCK overlap in most of the MDS patients with MK. TP53 mutations occur more frequently in MDS patients with vCK, and both TP53 mutations and vCK are adverse prognostic factors.

Prognostic value of DNMT3A mutations in myelodysplastic syndromes: a meta-analysis

Objectives: Although DNA (cytosine-5)-methyltransferase 3 alpha (DNMT3A) gene mutations have been widely reported in myelodysplastic syndromes (MDS), the prognostic significance of DNMT3A mutations is still controversial. In this study, we conducted a meta-analysis to determine the prognostic effect of DNMT3A mutations in patients with MDS. Methods: Eligible studies from PubMed, Embase, Web of Science, Clinical Trials and the Cochrane Library were searched. Hazard ratios (HRs) and their 95% confidence intervals (CIs) for overall survival (OS) and leukemia-free survival (LFS) were pooled to assess the effect of DNMT3A mutations on the prognosis in MDS patients. Results: A total of 12 studies with 2236 patients were included in this meta-analysis. The pooled HRs for OS and LFS revealed that MDS patients with DNMT3A mutations had a significantly poor prognosis as compared with those without mutations (OS: HR = 1.654, 95% CI = 1.387-1.973, p < 0.001; LFS: HR = 4.624, 95% CI = 3.121-6.851, p < 0.001). Discussion and Conclusion: This meta-analysis showed an adverse prognostic effect of DNMT3A mutations in patients with MDS, which will contribute to risk stratification and prognostic assessment in the disease.

Assessment of the clinical utility of four NGS panels in myeloid malignancies. Suggestions for NGS panel choice or design

The diagnosis of myeloid neoplasms (MN) has significantly evolved through the last few decades. Next Generation Sequencing (NGS) is gradually becoming an essential tool to help clinicians with disease management. To this end, most specialized genetic laboratories have implemented NGS panels targeting a number of different genes relevant to MN. The aim of the present study is to evaluate the performance of four different targeted NGS gene panels based on their technical features and clinical utility. A total of 32 patient bone marrow samples were accrued and sequenced with 3 commercially available panels and 1 custom panel. Variants were classified by two geneticists based on their clinical relevance in MN. There was a difference in panel’s depth of coverage. We found 11 discordant clinically relevant variants between panels, with a trend to miss long insertions. Our data show that there is a high risk of finding different mutations depending on the panel of choice, due both to the panel design and the data analysis method. Of note, CEBPA, CALR and FLT3 genes, remains challenging the use of NGS for diagnosis of MN in compliance with current guidelines. Therefore, conventional molecular testing might need to be kept in place for the correct diagnosis of MN for now.

Where Does Morphology Fit in Myelodysplastic Syndrome Diagnosis in the Era of Molecular Testing?

The recognition of cytologic dysplasia in blood and bone marrow remains the cornerstone of myelodysplastic syndromes (MDS) diagnosis because it distinguishes MDS from clonal hematopoiesis of indeterminate potential or clonal cytopenia of undetermined significance. Expert morphologists achieve high concordance in the diagnosis of MDS if appropriate clinical information is provided. Because of the low prevalence of MDS, diagnostic approaches based solely on molecular diagnosis will likely be erroneous.

Evaluation of different scoring systems and gene mutations for the prognosis of myelodysplastic syndrome (MDS) in Chinese population

MDS is a heterogeneous disease with diverse clinical manifestations, and an effective prognostic evaluation tool for MDS patients is needed. To achieve more accurate prognosis assessment for Chinese MDS patients, here we examined several scoring systems and explored the implications of gene mutations. The prognostic conditions were stratified against three different score systems (International Prognostic Scoring System (IPSS), WHO Prognostic Scoring System (WPSS), and Revised International Prognostic Scoring System (IPSS-R)) were retrospectively applied to 110 de novo MDS patients in study cohort in our hospital and the prognostic conditions were stratified respectively. IPSS-R out-performed the others, since it had less overlaps in survival curve, especially in the relatively low-risk group. Furthermore, genetic mutations were identified in 84 out of 110 patients and their association with overall survival (OS) were determined. Among them, sixty-three percent patients had at least one-point mutation, including thirty-five patients with normal karyotypes. The presence of TP53 mutations, but not TET2, DNMT3A or ASXL1 mutations was significantly correlated with shorter OS. A new model incorporating IPSS-R and TP53 mutations into survival analysis was proposed, and the prognostic value of this model was validated to be predominant in a 190-primary MDS patient independent cohort. Our data suggested that IPSS-R was more suitable for Chinese population. Attentions should be paid to the unfavourable mutations that might exert impact on the survival, especially in patients with relatively low risk.

Recent insights regarding the molecular basis of myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of clonal disorders characterized by the overproduction of mature blood cells that have an increased risk of thrombosis and progression to acute myeloid leukemia. Next-generation sequencing studies have provided key insights regarding the molecular mechanisms of MPNs. MPN driver mutations in genes associated with the JAK-STAT pathway include JAK2 V617F, JAK2 exon 12 mutations and mutations in MPL, CALR, and CSF3R. Cooperating driver genes are also frequently detected and also mutated in other myeloid neoplasms; these driver genes are involved in epigenetic methylation, messenger RNA splicing, transcription regulation, and signal transduction. In addition, other genetic factors such as germline predisposition, order of mutation acquisition, and variant allele frequency also influence disease initiation and progression. This review summarizes the current understanding of the genetic basis of MPN, and demonstrates how molecular pathophysiology can improve both our understanding of MPN heterogeneity and clinical practice.

Mutation status and burden can improve prognostic prediction of patients with lower-risk myelodysplastic syndromes

Patients with lower‐risk myelodysplastic syndromes (LR‐MDS) as defined by the International Prognostic Scoring System (IPSS) have more favorable prognosis in general, but significant inter‐individual heterogeneity exists. In this study, we examined the molecular profile of 15 MDS‐relevant genes in 159 patients with LR‐MDS using next‐generation sequencing. In univariate COX regression, shorter overall survival (OS) was associated with mutation status of ASXL1 (P = .001), RUNX1 (P = .031), EZH2 (P = .049), TP53 (P = .016), SRSF2 (P = .046), JAK2 (P = .040), and IDH2 (P = .035). We also found significantly shorter OS in patients with an adjusted TET2 variant allele frequency (VAF) ≥18% versus those with either an adjusted TET2 VAF <18% or without TET2 mutations (median: 20.4 vs 47.8 months; P = .020; HR = 2.183, 95%CI: 1.129‐4.224). After adjustment for IPSS, shorter OS was associated with mutation status of ASXL1 (P < .001; HR = 4.306, 95% CI: 2.144‐8.650), TP53 (P = .004; HR = 4.863, 95% CI: 1.662‐14.230) and JAK2 (P = .002; HR = 5.466, 95%CI: 1.848‐16.169), as well as adjusted TET2 VAF ≥18% (P = .008; HR = 2.492, 95% CI: 1.273‐4.876). Also, OS was increasingly shorter as the number of mutational factors increased (P < .001). A novel prognostic scoring system incorporating the presence/absence of the four independent mutational factors into the IPSS further stratified LR‐MDS patients into three prognostically different groups (P < .001). The newly developed scoring system redefined 10.1% (16/159) of patients as a higher‐risk group, who could not be predicted by the currently prognostic models. In conclusion, integration of the IPSS with mutation status/burden of certain MDS‐relevant genes may improve the prognostication of patients with LR‐MDS and could help identify those with worse‐than‐expected prognosis for more aggressive treatment.

Combining gene variants with clinical characteristics improves outcome prediction in Chinese patients with myelodysplastic syndromes

Genetic variants have been identified in the majority of myelodysplastic syndromes (MDS) patients and have considerably influenced the diagnosis, classification, risk stratification and treatment of MDS. To explore the prognostic significance of genomic variants and build a new prognostic scoring model, we performed next-generation sequencing of 51 known genes in 499 Chinese patients with MDS. Ultimately, the TP53, GATA2, DNMT3A, age and the revised International Prognostic Scoring System (IPSS-R) risk stratification were included in a new Cox model and divided into three prognostic categories, and had a better prediction of overall survival. The C-index of the new prognostic scoring model (0.772) was clearly better than IPSS-R risk stratification (0.717), which was validated in 163 cases. Moreover, the new model was also suitable for the prediction of OS for patients undergoing allogeneic hematopoietic stem cell transplantation. The inclusion of genomic variants and age into the IPSS-R could improve prognostic algorithms for MDS patients.

Prognostic impact of peripheral blood WT1-mRNA expression in patients with MDS

Few reports suggested a prognostic impact of Wilms'Tumor-1 (WT1)-mRNA overexpression in MDS, but translation into clinical routine was hampered by limited patients numbers, differing sample sources, non-standardized methods/cut-offs. To evaluate whether WT1-mRNA expression yields additional prognostic information, we measured peripheral blood (PB) WT1-mRNA expression in 94 MDS using a standardized assay offering a validated cut-off to discriminate between normal and WT1-mRNA overexpression. Overall, 54 patients (57%) showed WT1-mRNA overexpression, while 40 patients (43%) had normal WT1-mRNA expression. This enabled discrimination between MDS and both healthy controls and non-MDS cytopenias. Furthermore, WT1-mRNA expression correlated with WHO 2016 subcategories and IPSS-R as indicated by mean WT1-mRNA expression and frequency of WT1-mRNA overexpressing patients within respective subgroups. Regarding the entire group, PB WT1-mRNA expression was associated with prognosis, as those patients showing WT1-mRNA overexpression had higher risk for disease progression and AML transformation and accordingly shorter progression-free, leukemia-free and overall survival in univariate analysis. In multivariate analysis, prognostic impact of PB WT1-mRNA expression status was independent of IPSS-R and enabled more precise prediction of PFS, but not OS, within IPSS-R very low/low and intermediate risk groups. Overall, measuring PB WT1-mRNA appears valuable to support diagnostics and refine prognostication provided by the IPSS-R.

Spanish Guidelines for the use of targeted deep sequencing in myelodysplastic syndromes and chronic myelomonocytic leukaemia

The landscape of medical sequencing has rapidly changed with the evolution of next generation sequencing (NGS). These technologies have contributed to the molecular characterization of the myelodysplastic syndromes (MDS) and chronic myelomonocytic leukaemia (CMML), through the identification of recurrent gene mutations, which are present in >80% of patients. These mutations contribute to a better classification and risk stratification of the patients. Currently, clinical laboratories include NGS genomic analyses in their routine clinical practice, in an effort to personalize the diagnosis, prognosis and treatment of MDS and CMML. NGS technologies have reduced the cost of large-scale sequencing, but there are additional challenges involving the clinical validation of these technologies, as continuous advances are constantly being made. In this context, it is of major importance to standardize the generation, analysis, clinical interpretation and reporting of NGS data. To that end, the Spanish MDS Group (GESMD) has expanded the present set of guidelines, aiming to establish common quality standards for the adequate implementation of NGS and clinical interpretation of the results, hoping that this effort will ultimately contribute to the benefit of patients with myeloid malignancies.

How we manage adults with myelodysplastic syndrome

The prognosis in Myelodysplastic syndromes (MDS), although recently refined by molecular studies, remains largely based on conventional prognostic scores [International Prognostic Scoring System (IPSS), revised IPSS], classifying patients into "lower risk" MDS (LR-MDS) and "higher risk" MDS (HR-MDS). In LR-MDS, treatment mainly aims at improving cytopenias, principally anaemia, while in HR-MDS it aims at delaying disease progression and prolonging survival. In LR-MDS without deletion 5q, anaemia is generally treated first by erythropoietic stimulating factors, while second line treatments are currently not approved [lenalidomide, hypomethylating agents (HMA), luspatercept] or rarely indicated (antithymocyte globulin). Lenalidomide has major efficacy in LR-MDS with deletion 5q. Allogeneic stem cell transplantation (allo-SCT) is sometimes considered in LR-MDS, and iron chelation can be considered when multiple red blood cell transfusions are required. Allo-SCT is the only potentially curative treatment for HR-MDS; however, it is rarely applicable. It is generally preceded by intensive chemotherapy (IC) or HMA in patients with excess of marrow blasts (especially if >10%). In other patients, HMA can improve survival. The role of new drugs, including venetoclax or, in case of specific mutations, IDH1 or IDH2 inhibitors, is investigated. IC is mainly indicated as a bridge to allo-SCT, in the absence of unfavourable karyotype.

Next-generation sequencing-based minimal residual disease monitoring in patients receiving allogeneic hematopoietic stem cell transplantation for acute myeloid leukemia or myelodysplastic syndrome

PURPOSE OF REVIEW

The monitoring of minimal residual disease (MRD) has important clinical implications in both the pre and postallogeneic stem cell transplant (SCT) setting in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Next-generation sequencing (NGS) is a rapidly improving technology whose application to the monitoring of MRD is an active area of research. We aim to describe existing methods of MRD in AML and MDS, with a focus on the utility of NGS in patients undergoing SCT.

RECENT FINDINGS

Flow cytometry and quantitative PCR have been recommended by the European Leukemia Net as the preferred methods of MRD in AML and MDS, but these methods have limitations in cases without a disease-defining phenotype and genotype. Clinical trials are currently ongoing to assess the use of NGS in the setting of SCT for MDS and AML. Few studies have so far assessed the optimal method of MRD monitoring in the posttransplant setting.

SUMMARY

The optimal method for the monitoring of MRD in AML and MDS both pre and post transplant may require more than one technology. NGS holds great promise for the monitoring of MRD, with prospective trials currently ongoing to evaluate its efficacy in this regard.

TP53 mutation status divides myelodysplastic syndromes with complex karyotypes into distinct prognostic subgroups

Risk stratification is critical in the care of patients with myelodysplastic syndromes (MDS). Approximately 10% have a complex karyotype (CK), defined as more than two cytogenetic abnormalities, which is a highly adverse prognostic marker. However, CK-MDS can carry a wide range of chromosomal abnormalities and somatic mutations. To refine risk stratification of CK-MDS patients, we examined data from 359 CK-MDS patients shared by the International Working Group for MDS. Mutations were underrepresented with the exception of TP53 mutations, identified in 55% of patients. TP53 mutated patients had even fewer co-mutated genes but were enriched for the del(5q) chromosomal abnormality (p < 0.005), monosomal karyotype (p < 0.001), and high complexity, defined as more than 4 cytogenetic abnormalities (p < 0.001). Monosomal karyotype, high complexity, and TP53 mutation were individually associated with shorter overall survival, but monosomal status was not significant in a multivariable model. Multivariable survival modeling identified severe anemia (hemoglobin < 8.0 g/dL), NRAS mutation, SF3B1 mutation, TP53 mutation, elevated blast percentage (>10%), abnormal 3q, abnormal 9, and monosomy 7 as having the greatest survival risk. The poor risk associated with CK-MDS is driven by its association with prognostically adverse TP53 mutations and can be refined by considering clinical and karyotype features.

Treatment of myelodysplastic syndrome in the era of next-generation sequencing

Next-generation sequencing (NGS) is rapidly changing the clinical care of patients with myelodysplastic syndrome (MDS). NGS can be used for various applications: (i) in the diagnostic process to discriminate between MDS and other diseases such as aplastic anaemia, myeloproliferative disorders and idiopathic cytopenias; (ii) for classification, for example, where the presence of SF3B1 mutation is one criterion for the ring sideroblast anaemia subgroups in the World Health Organization 2016 classification; (iii) for identification of patients suitable for targeted therapy (e.g. IDH1/2 inhibitors); (iv) for prognostication, for example, where specific mutations (e.g. TP53 and RUNX1) are associated with inferior prognosis, whereas others (e.g. SF3B1) are associated with superior prognosis; and (v) to monitor patients for progression or treatment failure. Most commonly, targeted sequencing for genes (normally 50-100 genes) reported to be recurrently mutated in myeloid disease is used. At present, NGS is rarely incorporated into clinical guidelines although an increasing number of studies have demonstrated the benefit of using NGS in the clinical management of MDS patients.

Factors predicting early mortality after new diagnosis of myelodysplastic syndrome: A population-based study

OBJECTIVE

Little prospective data regarding factors determining patient outcomes in myelodysplastic syndromes (MDS) are available. To establish features of early mortality in MDS, we compare characteristics of patients dying within 1 year of diagnosis with those surviving longer.

METHODS

We prospectively enrolled adults with a new MDS diagnosis in a population-based case-control study. Logistic regression was used to calculate odds ratios and 95% confidence intervals for potential predictors of early mortality. Subgroup analyses were conducted within the following groups: high-/very-high-risk IPSS-R; very-low-/low-/intermediate-risk IPSS-R; treated patients; and supportive care only patients.

RESULTS

We observed early mortality in those with abnormal cytogenetics (OR: 3.36, 95% CI: 1.52-7.46), three or greater cytogenetic abnormalities (OR: 3.48, 95% CI: 1.51-7.99), treatment at a community medical center (versus academic) (OR: 2.55, 95% CI: 1.18-5.47), and with 2-3 concurrent medical comorbidities (OR: 2.14, 95% CI: 1.08-4.22). Similarly, in subgroup analyses, abnormal cytogenetics remained the main predictor of early mortality.

CONCLUSION

Complex cytogenetics and prognostic risk category have been associated with early mortality without intervention. Our data confirm these associations in a large, prospectively followed cohort and highlight the significance of cytogenetic abnormalities and complexity regardless of IPSS-R risk categorization or treatment.

Outcome and Prognostic Factors of High-Risk Acute Myeloid Leukemia After Allogeneic Hematopoietic Stem Cell Transplantation

Background

Allogeneic transplantation remains one of the best therapies for high-risk acute myeloid leukemia (HR-AML).

Material/Methods

This study retrospectively analyzed 126 patients with HR-AML after allogeneic hematopoietic stem cell transplantation (allo-HCST).

Results

The disease-free survival (DFS) rates of 1 year and 3 years were 58.83% (95%CI: 50.75–68.20%) and 53.09% (95%CI: 44.59–63.22%) respectively. The cumulative relapse rates of 1 year and 3 years were 21.1% (95%CI: 14.4–28.8%) and 25.9% (95%CI: 18.1–34.5%) respectively. The cumulative incidences of III to IV acute graft-versus-host disease (aGVHD) for 100 days was 8.70% (95%CI: 4.6–14.5%). The cumulative rate of extensive chronic graft-versus-host disease (cGVHD) for 1-year was 4.1% (95%CI: 1.5–8.7%). The cumulative transplantation related mortality rate of 1 year and 3 years were 20.1% (95%CI: 13.6–27.6%) and 21.0% (95%CI: 14.3–28.6%) respectively. Univariate analysis revealed that lower overall survival was correlated with age, bacterial or fungal infection, disease status at transplantation, III–IV aGVHD, post-transplantation lymphoproliferative disorders (PTLD), white blood cell engraftment, and extramedullary involvement (P<0.05). The results of multivariate analysis were that the aforementioned factors were also related to lower overall survival except for PTLD (P<0.05). The results of univariate and multivariate analysis were that extramedullary involvement, III–IV aGVHD, and status pre-transplantation influenced DFS (P<0.05). The risk factors for relapse were status pre-transplantation and extramedullary involvement by univariate and multivariate analysis (P<0.05).

Conclusions

HR-AML has inferior prognosis. Our study indicated the necessity of achieving remission status prior to hematopoietic stem cell transplantation, and administration of preventive treatments on high-risk patients after hematopoietic stem cell transplantation. In addition, adequate prevention and treatment of complications are needed.

Current status and new treatment approaches in TP53 mutated AML

Mutations in the essential tumor suppressor gene, TP53, are observed in only 5-10% of acute myeloid leukemia (AML) cases, but are highly associated with therapy-related AML and cases with complex karyotype. The mutational status of TP53 is a critical prognostic indicator, with dismal outcomes consistently observed across studies. Response rates to traditional cytotoxic chemotherapy are poor and long-term survival after allogeneic hematopoietic stem cell transplant is rare. Therapy with hypomethylating agents has resulted in a modest improvement in outcomes over intensive chemotherapy, but durable responses are seldom observed. In view of the intrinsic resistance to standard chemotherapies conferred by mutations in TP53, novel treatment approaches are required. In this review, we examine the current treatment landscape in TP53 mutated AML and discuss emerging therapeutic approaches currently under clinical investigation.

Does SF3B1/TET2 Double Mutation Portend Better or Worse Prognosis Than Isolated SF3B1 or TET2 Mutation?

BACKGROUND

Mutations in splicing factor 3b subunit 1 (SF3B1) have been reported to be associated with a favorable prognosis, while the prognostic impact of tet methylcytosine dioxygenase 2 (TET2) mutations is still controversial. The clinical significance of combined SF3B1 and TET2 mutation is even more uncertain. In this study, the clinical consequences of concurrent double SF3B1/TET2 mutation were compared with isolated SF3B1 or TET2 mutation.

MATERIALS AND METHODS

The demographics, diagnosis, cytogenetic abnormalities, and overall survival time of 130 patients with isolated SF3B1 (n=48) or TET2 mutation (n=54), or double SF3B1/TET2 mutation (n=28) were compared by next-generation sequencing.

RESULTS

Patients with double mutation were found to be significantly older than patients with isolated TET2 mutation. Patients with double mutation or isolated SF3B1 mutation were less likely to be diagnosed with acute myeloid leukemia than patients with isolated TET2 mutation. Patients with myelodysplasia had a higher percentage of double or isolated SF3B1 mutation, while patients with myeloproliferative neoplasms had a higher percentage of isolated TET2 mutation. Patients with double mutation more frequently had increased ring sideroblasts similarly to patients with isolated SF3B1 mutation. The percentage of patients with normal cytogenetics or good cytogenetic abnormalities was significantly higher in patients with double mutation than those with isolated mutation. Finally, in patients with myelodysplasia and normal cytogenetics, the median survival time in those with double mutation was significantly longer than in those with isolated SF3B1 mutation, even though the overall survival curve was not statistically significant.

CONCLUSION

TET2 mutation appeared not to have additional effects when combined with SF3B1, and patients with double mutation appeared to have at least as, good as or even better prognosis than patients with isolated mutation.

Indications for haematopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2019

This is the seventh special EBMT report on the indications for haematopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders. Our aim is to provide general guidance on transplant indications according to prevailing clinical practice in EBMT countries and centres. In order to inform patient decisions, these recommendations must be considered together with the risk of the disease, the risk of the transplant procedure and the results of non-transplant strategies. In over two decades since the first report, the EBMT indications manuscripts have incorporated changes in transplant practice coming from scientific and technical developments in the field. In this same period, the establishment of JACIE accreditation has promoted high quality and led to improved outcomes of patient and donor care and laboratory performance in transplantation and cellular therapy. An updated report with operating definitions, revised indications and an additional set of data with overall survival at 1 year and non-relapse mortality at day 100 after transplant in the commonest standard-of-care indications is presented. Additional efforts are currently underway to enable EBMT member centres to benchmark their risk-adapted outcomes as part of the Registry upgrade Project 2020 against national and/or international outcome data.

Getting personal with myelodysplastic syndromes: is now the right time?

INTRODUCTION

Commonly used scoring systems rely on blood counts, histological and cytological examination of bone marrow and peripheral blood as well as cytogenetic assessments to estimate prognosis of patients with myelodysplastic syndromes (MDS) and guide therapy decisions. Next-generation sequencing (NGS) has identified recurrent genetic abnormalities in up to 90% of patients with MDS and may provide important information regarding the pathogenesis of the disease, diagnostic and prognostic evaluation, and therapy selection. Areas covered: Herein, the authors review the role of NGS in diagnosis, treatment, and prognosis of MDS at various disease stages, and discuss advantages and caveats of incorporating molecular genetics in routine management of MDS. While a vast majority of patients harbor recurrent mutations implicated in MDS pathogenesis, similar mutations can be detected in otherwise healthy individuals with other hematologic malignancies. Besides establishing a diagnosis, NGS may be used to monitor minimal residual disease following treatment. Expert opinion: As more targeted therapies become available, assessment of genetic mutations will become central to individualized therapy selection and may improve diagnostic accuracy and further guide management for each patient. However, multiple challenges remain before NGS can be incorporated into routine clinical practice.

Increased opportunity for prolonged survival after allogeneic hematopoietic stem cell transplantation in patients aged 60-69 years with myelodysplastic syndrome

We conducted a nationwide retrospective study to evaluate the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in 651 patients aged 60-69 years with de novo myelodysplastic syndrome (MDS). We divided patients into two groups: 152 and 499 patients with an early and advanced disease status, respectively. The 3-year overall survival (OS) rate of patients with an early disease status was 45.9% (95% confidence interval [CI], 37.0 to 54.2%). A multivariate analysis revealed five adverse factors for OS: performance status (PS) 2-4 (hazard ratio [HR] 4.48; P < .001), poor cytogenetic risk group (HR 1.83; P = .041), male recipient (HR 2.58; P = .003), use of HLA-mismatched related grafts (HR 4.75; P = .003), and unrelated cord blood (HR 2.47; P = .023). The 3-year OS rate of patients with an advanced disease status was 37.2% (95% CI 32.4 to 41.9%). Five factors correlated with worse OS: PS 2-4 (HR 1.72; P = .003), poor cytogenetic risk group (HR 1.49; P = .003), use of HLA-mismatched related grafts (HR 1.96; P = .015), unrelated cord blood (HR 2.05; P < .001), and the high number of red blood cell transfusions before transplantation (HR 1.85; P = .018). The present results revealed the more frequent utilization of allo-HSCT for MDS patients aged 60-69 years, which increases the curative potential.

Clinical impact of the loss of chromosome 7q on outcomes of patients with myelodysplastic syndromes treated with allogeneic hematopoietic stem cell transplantation

We conducted a nationwide retrospective study to evaluate the prognostic influence of +1, der(1;7)(q10;p10) [hereafter der(1;7)] and -7/del(7q) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for de novo myelodysplastic syndromes (MDS). In this database, 69 MDS patients with der(1;7), 75 with -7/del(7q), and 511 with normal karyotype (NK) underwent allo-HSCT at advanced disease status. The 3-year overall survival (OS) and cumulative incidence of relapse (CIR) were 50.4 and 19.4% for those with der(1;7), 36.2 and 38.4% for -7/del(7q), and 51.1 and 20.7% for NK, respectively. In the multivariate analysis, the presence of -7/del(7q) correlated with a significantly shorter OS (HR [95% CI], 1.38 [1.00-1.89]; P = 0.048) and higher CIR (HR, 2.11 [1.36-3.28]; P = 0.001) than those with NK. There were 23 patients with der(1;7), 29 with -7/del(7q), and 347 with NK who underwent allo-HSCT at early disease status. The 3-year OS and CIR were as follows: 47.3 and 9.5% for the der(1;7) group, 70.5 and 13.8% for -7/del(7q), and 70.9 and 5.6% for NK, respectively. No significant differences were observed in OS and CIR among three groups. The impact of the loss of chromosome 7q on OS and CIR may differ based on its type and disease status after allo-HSCT for MDS.

Genetics of MDS

Our knowledge about the genetics of myelodysplastic syndromes (MDS) and related myeloid disorders has been dramatically improved during the past decade, in which revolutionized sequencing technologies have played a major role. Through intensive efforts of sequencing of a large number of MDS genomes, a comprehensive registry of driver mutations recurrently found in a recognizable fraction of MDS patients has been revealed, and ongoing efforts are being made to clarify their impacts on clinical phenotype and prognosis, as well as their role in the pathogenesis of MDS. Among major mutational targets in MDS are the molecules involved in DNA methylations, chromatin modification, RNA splicing, transcription, signal transduction, cohesin regulation, and DNA repair. Showing substantial overlaps with driver mutations seen in acute myeloid leukemia (AML), as well as age-related clonal hematopoiesis in healthy individuals, these mutations are presumed to have a common clonal origin. Mutations are thought to be acquired and positively selected in a well-organized manner to allow for expansion of the initiating clone to compromise normal hematopoiesis, ultimately giving rise to MDS and subsequent transformation to AML in many patients. Significant correlations between mutations suggest the presence of functional interactions between mutations, which dictate disease progression. Mutations are frequently associated with specific disease phenotype, drug response, and clinical outcomes, and thus, it is essential to be familiar with MDS genetics for better management of patients. This review aims to provide a brief overview of the recent progresses in MDS genetics.

Therapeutic choices after hypomethylating agent resistance for myelodysplastic syndromes

PURPOSE OF REVIEW

Hypomethylating agents (HMAs) are the standard of care for patients with myelodysplastic syndromes (MDS). Although these agents induce responses in up to 40% of patients, most patients ultimately experience loss of response. The purpose of this review is to provide an overview of the different therapies under development for MDS after HMA therapy.

RECENT FINDINGS

Recent advances in the understanding of MDS pathogenesis have led to the development of new potential therapies after HMA failure. Newer HMAs, less susceptible to in-vivo deamination, such as guadecitabine or ASTX727 have shown activity. Alterations of immune checkpoints in MDS have led to multiple clinical trials evaluating the activity of monoclonal antibodies targeting these proteins (pembrolizumab, nivolumab, ipilimumab). Different combinations and new formulations of cytotoxic agents, such as clofarabine or CPX-351, are newer options for specific subsets of patients. Finally, targeted agents inhibiting multiple kinases (rigosertib), BCL2 (venetoclax) or mutant IDH1 (ivosidenib), IDH2 (enasidenib), FLT3 (sorafenib, midostaurin) or spliceosome components (H3B-8800) are other novel options.

SUMMARY

Despite the poor prognosis associated with HMA failure, clinical trials, new cytotoxic agents and allogeneic stem-cell transplantation, can offer therapeutic opportunities for these patients for whom there is no standard of care.

Impact of High-Molecular-Risk Mutations on Transplantation Outcomes in Patients with Myelofibrosis

Mutational profiling has demonstrated utility in predicting the likelihood of disease progression in patients with myelofibrosis (MF). However, there is limited data regarding the prognostic utility of genetic profiling in MF patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HCT). We performed high-throughput sequencing of 585 genes on pre-transplant samples from 101 patients with MF who underwent allo-HCT and evaluated the association of mutations and clinical variables with transplantation outcomes. Overall survival (OS) at 5 years post-transplantation was 52%, and relapse-free survival (RFS) was 51.1 % for this cohort. Nonrelapse mortality (NRM) accounted for most deaths. Patient's age, donor's age, donor type, and Dynamic International Prognostic Scoring System score at diagnosis did not predict for outcomes. Mutations known to be associated with increased risk of disease progression, such as ASXL1, SRSF2, IDH1/2, EZH2, and TP53, did not impact OS or RFS. The presence of U2AF1 (P = .007) or DNMT3A (P = .034) mutations was associated with worse OS. A Mutation-Enhanced International Prognostic Scoring System 70 score was available for 80 patients (79%), and there were no differences in outcomes between patients with high risk scores and those with intermediate and low risk scores. Collectively, these data identify mutational predictors of outcome in MF patients undergoing allo-HCT. These genetic biomarkers in conjunction with clinical variables may have important utility in guiding transplantation decision making.

The MDS genomics-prognosis symbiosis

Myelodysplastic syndromes (MDS) are clonal disorders characterized by the accumulation of complex genomic abnormalities that define disease phenotype, prognosis, and the risk of transformation to acute myeloid leukemia. The clinical manifestations and overall outcomes of MDS are very heterogeneous with an overall survival that can be measured in years for some patients to a few months for others. Prognostic scoring systems are important staging tools that aid physicians in their treatment recommendations and decision-making and can help patients understand their disease trajectory and expectations. Several scoring systems have been developed in MDS with the International Prognostic Scoring System and its revised version, the most widely used systems in clinical practice and trial eligibility. These models and others use mainly clinical variables that are obtained from bone marrow biopsy and peripheral blood measurements. Adding molecular data to current models may improve its predictive power but the ultimate method to incorporate this information remains a work in progress. Novel methods to develop a personalized prediction model that provides outcomes that are specific for a patient are currently under way and may change how we think about risk stratification in MDS patients in the future.

Treatments targeting MDS genetics: a fool's errand?

The myelodysplastic syndromes are collectively the most common myeloid neoplasms. Clonal hematopoiesis present in these diseases results in bone marrow failure characteristically seen in patients. The heterogeneity of myelodysplastic syndrome pathobiology has historically posed a challenge to the development of newer therapies. Recent advances in molecular characterization of myelodysplastic syndromes are improving diagnostic accuracy, providing insights into pathogenesis, and refining therapeutic options for patients. With the advent of these developments, appropriately chosen therapeutics or even targeted agents may be able to improve patient outcomes in the future.