Role of reduced-intensity conditioning allogeneic hematopoietic stem-cell transplantation in older patients with de novo myelodysplastic syndromes: an international collaborative decision analysis

Molecular prognostication for transplant decision making of patients with myelodysplastic syndromes: A retrospective single-center study

Allogeneic hematopoietic stem cell transplantation (HSCT) remains the only curative option for patients with Myelodysplastic syndromes (MDS). For many years, the selection of patients to allogeneic HSCT has been largely based on use of the International Prognostic Scoring System-Revised (IPSS-R). However, the recent broader application of next generation sequencing in clinical practice provided an abundance of molecular data and led to the introduction of molecular prognostic scores as IPSS-Molecular (IPSS-M). In this paper, we retrospectively analyzed the outcomes of 57 consecutive MDS patients treated with allogeneic HSCT in our center. Re-stratification from IPSS-R to IPSS-M occurred in almost half of patients. The application of IPSS-M to our cohort demonstrated a stronger prognostic separation compared to IPSS-R and improved the C-index. Very high-risk IPSS-M patients showed worse outcomes following HSCT compared to high-risk patients. This study provides data supporting the need of integrating molecular information in the transplant decision making of patients with MDS. This allows an earlier and better identification of patients to whom the transplant should be advised.

Revisiting Timing and Decision Modeling for Allogeneic Hematopoietic Stem-Cell Transplantation in Myelodysplastic Syndromes

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Treatment of Myelodysplastic Syndromes for Older Patients: Current State of Science, Challenges, and Opportunities

PURPOSE OF REVIEW

Myelodysplastic syndromes/neoplasms (MDS) represent a diverse group of pathologically distinct diseases with varying prognoses and risks of leukemia progression. This review aims to discuss current treatment options for elderly patients with MDS, focusing on patients ineligible for intensive chemotherapy or allogenic hematopoietic stem cell transplantation (HSCT). The challenges associated with treatment in this population and emerging therapeutic prospects are also explored.

RECENT FINDINGS

Recent advancements in molecular diagnostics have enhanced risk stratification by incorporating genetic mutations, notably through the molecular International Prognostic Scoring System (IPSS-M). Lower-risk MDS (LR-MDS) treatment ranges from observation to supportive measures and erythropoiesis-stimulating agents (ESAs), with emerging therapies like luspatercept showing promise. High-risk MDS (HR-MDS) is treated with hypomethylating agents (HMAs) or allogenic HSCT, but outcomes remain poor. Elderly MDS patients, often diagnosed after 70, pose challenges in treatment decision-making. The IPSS-M aids risk stratification, guiding therapeutic choices. For LR-MDS, supportive care, ESAs, and novel agents like luspatercept are considered. Treatment of HR-MDS involves HMAs or allogenic HSCT. Emerging treatments, including oral HMAs and novel agents targeting FLT3, and IDH 1/2 mutations, show promise. Future research should refine treatment strategies for this elderly population focusing on quality-of-life improvement.

Chronic myelomonocytic leukemia: 2024 update on diagnosis, risk stratification and management

DISEASE OVERVIEW

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic stem cell disorder with overlapping features of myelodysplastic syndromes and myeloproliferative neoplasms, characterized by prominent monocytosis and an inherent risk for leukemic transformation (~15%-20% over 3-5 years).

DIAGNOSIS

Newly revised diagnostic criteria include sustained (>3 months) peripheral blood (PB) monocytosis (≥0.5 × 109/L; monocytes ≥10% of leukocyte count), consistent bone marrow (BM) morphology, <20% BM or PB blasts (including promonocytes), and cytogenetic or molecular evidence of clonality. Cytogenetic abnormalities occur in ~30% of patients, while >95% harbor somatic mutations: TET2 (~60%), SRSF2 (~50%), ASXL1 (~40%), RAS pathway (~30%), and others. The presence of ASXL1 and DNMT3A mutations and absence of TET2 mutations negatively impact overall survival (ASXL1WT/TET2MT genotype being favorable).

RISK STRATIFICATION

Several risk models serve similar purposes in identifying high-risk patients that are considered for allogeneic stem cell transplant (ASCT) earlier than later. Risk factors in the Mayo Molecular Model (MMM) include presence of truncating ASXL1 mutations, absolute monocyte count >10 × 109/L, hemoglobin <10 g/dL, platelet count <100 × 109/L, and the presence of circulating immature myeloid cells; the resulting 4-tiered risk categorization includes high (≥3 risk factors), intermediate-2 (2 risk factors), intermediate-1 (1 risk factor), and low (no risk factors); the corresponding median survivals were 16, 31, 59, and 97 months. CMML is also classified as being "myeloproliferative (MP-CMML)" or "myelodysplastic (MD-CMML)," based on the presence or absence of leukocyte count of ≥13 × 109/L.

TREATMENT

ASCT is the only treatment modality that secures cure or long-term survival and is appropriate for MMM high/intermediate-2 risk disease. Drug therapy is currently not disease-modifying and includes hydroxyurea and hypomethylating agents; a recent phase-3 study (DACOTA) comparing hydroxyurea and decitabine, in high-risk MP-CMML, showed similar overall survival at 23.1 versus 18.4 months, respectively, despite response rates being higher for decitabine (56% vs. 31%).

UNIQUE DISEASE ASSOCIATIONS

These include systemic inflammatory autoimmune diseases, leukemia cutis and lysozyme-induced nephropathy; the latter requires close monitoring of renal function during leukocytosis and is a potential indication for cytoreductive therapy.

Management of adult patients with CMML undergoing allo-HCT: recommendations from the EBMT PH&G Committee

ABSTRACT

Chronic myelomonocytic leukemia (CMML) is a heterogeneous disease presenting with either myeloproliferative or myelodysplastic features. Allogeneic hematopoietic cell transplantation (allo-HCT) remains the only potentially curative option, but the inherent toxicity of this procedure makes the decision to proceed to allo-HCT challenging, particularly because patients with CMML are mostly older and comorbid. Therefore, the decision between a nonintensive treatment approach and allo-HCT represents a delicate balance, especially because prospective randomized studies are lacking and retrospective data in the literature are conflicting. International consensus on the selection of patients and the ideal timing of allo-HCT, specifically in CMML, could not be reached in international recommendations published 6 years ago. Since then, new, CMML-specific data have been published. The European Society for Blood and Marrow Transplantation (EBMT) Practice Harmonization and Guidelines (PH&G) Committee assembled a panel of experts in the field to provide the first best practice recommendations on the role of allo-HCT specifically in CMML. Recommendations were based on the results of an international survey, a comprehensive review of the literature, and expert opinions on the subject, after structured discussion and circulation of recommendations. Algorithms for patient selection, timing of allo-HCT during the course of the disease, pretransplant strategies, allo-HCT modality, as well as posttransplant management for patients with CMML were outlined. The keynote message is, that once a patient has been identified as a transplant candidate, upfront transplantation without prior disease-modifying treatment is preferred to maximize chances of reaching allo-HCT whenever possible, irrespective of bone marrow blast counts.

Prognostic impact of the conditioning intensity on outcomes after allogeneic transplantation for MDS with low blasts: a nationwide retrospective study by the adult MDS working group of the Japan Society for Transplantation and Cellular Therapy

Poor prognostic factors, such as transfusion dependency and chromosomal risk, need to be considered in the indication of allogeneic hematopoietic cell transplantation (allo-HCT) for patients harboring myelodysplastic syndromes with less than 5% marrow blasts (MDS-Lo). We analyzed the post-transplant outcomes of 1229 MDS-Lo patients who received myeloablative (MAC)(n = 651), reduced-intensity (RIC)(n = 397), and non-myeloablative conditioning (NMAC) regimens (n = 181). The multivariate analysis revealed that the RIC group had better chronic graft-versus-host disease (GVHD)- and relapse-free survival (CRFS) (P = 0.021), and GVHD- and relapse-free survival (GRFS) than the MAC group (P = 0.001), while no significant differences were observed between the NMAC and MAC groups. In the subgroup analysis, the MAC group has better overall survival (P = 0.008) than the RIC group among patients with an HCT-comorbidity index (HCT-CI) score of 0, while the RIC group had better overall survival (P = 0.029) than the MAC group among those with an HCT-CI score ≥3. According to the type of conditioning regimen, total body irradiation 12 Gy-based MAC regimen showed better OS and CRFS than the other MAC regimen, and comparable outcomes to the RIC regimen. In conclusion, the RIC and NMAC regimens are promising options for MDS-Lo patients in addition to the MAC regimen.

Advances in the management of higher-risk myelodysplastic syndromes: future prospects

Higher-risk myelodysplastic syndromes (HR-MDS) are defined using a number of prognostic scoring systems that include the degree of cytopenias, percentage of blasts, cytogenetic alterations, and more recently genomic data. HR-MDS encompasses characteristics such as progressive cytopenias, increased bone marrow blasts, unfavorable cytogenetics, and an adverse mutational profile. Survival is generally poor, and patients require therapy to improve outcomes. Hypomethylating agents (HMAs), such as azacitidine, decitabine, and more recently, oral decitabine/cedazuridine, are the only approved therapies for HR-MDS. These are often continued until loss of response, progression, or unacceptable toxicity. Combinations including an HMA plus other drugs have been investigated but have not demonstrated better outcomes compared to single-agent HMA. Moreover, in a disease of high genomic complexity such as HR-MDS, therapy targeting specific genomic abnormalities is of interest. This review will examine the biological underpinnings of HR-MDS, its therapeutic landscape in the frontline and relapsed settings, as well as the impact of hematopoietic stem cell transplantation, the only known curative intervention for this disease.

How I reduce and treat posttransplant relapse of MDS

ABSTRACT

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only potentially curative option for patients with high-risk myelodysplastic syndromes (MDS). Advances in conditioning regimens and supportive measures have reduced treatment-related mortality and increased the role of transplantation, leading to more patients undergoing HSCT. However, posttransplant relapse of MDS remains a leading cause of morbidity and mortality for this procedure, necessitating expert management and ongoing results analysis. In this article, we review treatment options and our institutional approaches to managing MDS relapse after HSCT, using illustrative clinical cases that exemplify different clinical manifestations and management of relapse. We address areas of controversy relating to conditioning regimen intensity, chemotherapeutic bridging, and donor selection. In addition, we discuss future directions for advancing the field, including (1) the need for prospective clinical trials separating MDS from acute myeloid leukemia and focusing on posttransplant relapse, as well as (2) the validation of measurable residual disease methodologies to guide timely interventions.

Myelodysplastic Neoplasms (MDS): The Current and Future Treatment Landscape

Myelodysplastic neoplasms (MDS) are a heterogenous clonal disorder of hemopoietic stem cells characterized by cytomorphologic dysplasia, ineffective hematopoiesis, peripheral cytopenias and risk of progression to acute myeloid leukemia (AML). Our understanding of this disease has continued to evolve over the last century. More recently, prognostication and treatment have been determined by cytogenetic and molecular data. Specific genetic abnormalities, such as deletion of the long arm of chromosome 5 (del(5q)), TP53 inactivation and SF3B1 mutation, are increasingly associated with disease phenotype and outcome, as reflected in the recently updated fifth edition of the World Health Organization Classification of Hematolymphoid Tumors (WHO5) and the International Consensus Classification 2022 (ICC 2022) classification systems. Treatment of lower-risk MDS is primarily symptom directed to ameliorate cytopenias. Higher-risk disease warrants disease-directed therapy at diagnosis; however, the only possible cure is an allogenic bone marrow transplant. Novel treatments aimed at rational molecular and cellular pathway targets have yielded a number of candidate drugs over recent years; however few new approvals have been granted. With ongoing research, we hope to increasingly offer our MDS patients tailored therapeutic approaches, ultimately decreasing morbidity and mortality.

Hematopoietic cell transplantation (HCT) in MDS patients of older age

Hematopoietic cell transplantation (HCT) has evolved to an essential treatment in younger and more recently in elderly patients with myelodysplastic syndrome (MDS), the age group with the highest incidence. Less intense conditioning regimens and improvements in supportive therapy have reduced considerably transplant related mortality and in the same time increased the access to this curative treatment. Timing of HCT in the course of the disease assumes a crucial role. Detection of disease progression, geriatric assessment, comorbidity evaluation, and identification of transplant-specific risks are becoming increasingly important in this context. Novel statistical methods, molecular biomarkers, and quantification of tumor burden pre- and post-HCT will play an essential role in years to come. More effective and less toxic treatments to reduce the tumor burden before and/or after HCT are expected to improve the outcome. In this review article we discuss the current views and what we can expect.

Outcomes of transplant-eligible patients with myelodysplastic syndrome with excess blasts registered in an observational study: The JALSG-CS11-MDS-SCT

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is the sole curative therapy for myelodysplastic syndrome (MDS). However, whether bridging therapy (BRT) including azacitidine (AZA) and combination chemotherapy (CCT) prior to allo-SCT should be performed is unclear. We analyzed BRT and the outcomes of patients with myelodysplastic syndrome with excess blasts (MDS-EB) who were ≤ 70 years old at the time of registration for a prospective observational study to clarify the optimal allo-SCT strategy for high-risk MDS. A total of 371 patients were included in this study. Among 188 patients (50.7%) who were considered for allo-SCT, 141 underwent allo-SCT. Among the patients who underwent allo-SCT, 64 received AZA, 29 received CCT, and 26 underwent allo-SCT without BRT as the initial treatment. Multivariate analysis identified BRT as an independent factor influencing overall survival (AZA vs. without BRT, hazard ratio [HR] 3.33, P = 0.005; CCT vs. without BRT, HR 3.82, P = 0.003). In multivariate analysis, BRT was independently associated with progression-free survival (AZA vs. without BRT: HR, 2.23; P = 0.041; CCT vs. without BRT: HR, 2.94; P = 0.010). Transplant-eligible patients with MDS-EB should undergo allo-SCT when clinically acceptable, and upfront allo-SCT without BRT may be superior to AZA or CCT.

[Allogeneic hematopoietic stem cell transplantation for myelodysplastic syndromes]

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is one of the treatment options for myelodysplastic syndromes (MDS). This treatment is indicated as first-line treatment for high-risk MDS according to the IPSS and R-IPSS classifications and improves overall survival and progression-free survival. However, allo-HSCT is not indicated in first intention for low-risk MDS. It can be discussed in case of cytopenias needing transfusions, poor evolution under other treatment, or in case of poor prognosis molecular anomaly. Allo-HSCT is a treatment that can be complicated by early or late toxicities (graft versus host disease, infections, chemotherapy toxicity…). The decision to do an allo-HSCT is based on the benefit/risk ratio between the risk of progression from MDS to myeloid leukemia and the risk of transplant related mortality, which increases with the patient's age and comorbidities. The indication of a cytoreductive treatment before allo-HSCT depends on the blasts count, and on the delay before the allograft. The use of reduced intensity conditioning regimen and alternative donors such as haploidentical donors, expanded the indications for allo-HSCT. Relapse remains one of the main causes of mortality after allo-HSCT. Some genetic mutations and karyotype anomalies increase the risk of post-transplant relapse. Preventive treatments for relapse are currently being studied. Treatments such as azacytidine, donor lymphocytes infusions or targeted therapies can be used, prophylactically or preemptively.

Allogeneic Hematopoietic Cell Transplantation Improves Outcome in Myelodysplastic Syndrome Across High-Risk Genetic Subgroups: Genetic Analysis of the Blood and Marrow Transplant Clinical Trials Network 1102 Study

PURPOSE

Allogeneic hematopoietic cell transplantation (HCT) in patients with myelodysplastic syndrome (MDS) improves overall survival (OS). We evaluated the impact of MDS genetics on the benefit of HCT in a biological assignment (donor v no donor) study.

METHODS

We performed targeted sequencing in 309 patients age 50-75 years with International Prognostic Scoring System (IPSS) intermediate-2 or high-risk MDS, enrolled in the Blood and Marrow Transplant Clinical Trials Network 1102 study and assessed the association of gene mutations with OS. Patients with TP53 mutations were classified as TP53multihit if two alleles were altered (via point mutation, deletion, or copy-neutral loss of heterozygosity).

RESULTS

The distribution of gene mutations was similar in the donor and no donor arms, with TP53 (28% v 29%; P = .89), ASXL1 (23% v 29%; P = .37), and SRSF2 (16% v 16%; P = .99) being most common. OS in patients with a TP53 mutation was worse compared with patients without TP53 mutation (21% ± 5% [SE] v 52% ± 4% at 3 years; P < .001). Among those with a TP53 mutation, OS was similar between TP53single versus TP53multihit (22% ± 8% v 20% ± 6% at 3 years; P = .31). Considering HCT as a time-dependent covariate, patients with a TP53 mutation who underwent HCT had improved OS compared with non-HCT treatment (OS at 3 years: 23% ± 7% v 11% ± 7%; P = .04), associated with a hazard ratio of 3.89; 95% CI, 1.87 to 8.12; P < .001 after adjustment for covariates. OS among patients with molecular IPSS (IPSS-M) very high risk without a TP53 mutation was significantly improved if they had a donor (68% ± 10% v 0% ± 12% at 3 years; P = .001).

CONCLUSION

HCT improved OS compared with non-HCT treatment in patients with TP53 mutations irrespective of TP53 allelic status. Patients with IPSS-M very high risk without a TP53 mutation had favorable outcomes when a donor was available.

Treatment strategy at the decision for allogeneic transplantation in patients with myelodysplastic syndrome in the era of azacitidine: A KSGCT prospective study

The optimal bridge strategy at the decision for allogeneic hematopoietic stem cell transplantation (HSCT) in patients with myelodysplastic syndrome (MDS) is unclear. We performed a prospective observational study in which 110 patients with MDS who were decided to undergo HSCT were enrolled. Among these 110 patients, 77 patients were enrolled in this study within 1 month from the decision for HSCT. Among these 77 patients, 13 patients had a human leukocyte antigen (HLA)-matched sibling, 54 patients started an unrelated donor search, and the other 10 patients directly selected cord blood (CB) at the decision for HSCT, and 13 (100%), 38 (70.4%), and 9 (90%) patients actually underwent HSCT within 1 year, respectively. The overall survival (OS) at 1 year from their enrollment was 70.9%, and the selection of azacitidine use at the decision for HSCT was not associated with OS. Among 60 of the 77 patients who actually underwent HSCT within a year from their enrollment, a lower relapse rate after HSCT was observed in those who selected CB at the decision to undergo HSCT. However, this preferable effect of CB selection disappeared when patients who were enrolled in this study in > 1 month from the decision for HSCT were additionally included in the analyses. In conclusion, the selection of bridge strategy at the decision for HSCT did not affect outcomes in patients with MDS. The immediate performance of HSCT may be associated with better outcomes.

Novel risk assessment for the intensity of conditioning regimen in older patients

Reduced-intensity conditioning (RIC) regimens have long-term outcomes that are generally comparable with those of myeloablative conditioning (MAC) because of a lower risk of nonrelapse mortality (NRM) but a higher risk of relapse. However, it is unclear how we should select the conditioning intensity in individual cases. We propose the risk assessment for the intensity of conditioning regimen in elderly patients (RICE) score. We retrospectively analyzed 6147 recipients aged 50 to 69 years using a Japanese registry database. Based on the interaction analyses, advanced age (≥60 years), hematopoietic cell transplantation-specific comorbidity index (≥2), and umbilical cord blood were used to design a scoring system to predict the difference in an individual patient's risk of NRM between MAC and RIC: the RICE score, which is the sum of the 3 factors. Zero or 1 implies low RICE score and 2 or 3, high RICE score. In multivariate analyses, RIC was significantly associated with a decreased risk of NRM in patients with a high RICE score (training cohort: hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.60-0.90; P = .003; validation cohort: HR, 0.57; 95% CI, 0.43-0.77; P < .001). In contrast, we found no significant differences in NRM between MAC and RIC in patients with a low RICE score (training cohort: HR, 0.99; 95% CI, 0.85-1.15; P = .860; validation cohort: HR, 0.81; 95% CI, 0.66-1.01; P = .061). In summary, a new and simple scoring system, the RICE score, appears to be useful for personalizing the conditioning intensity and could improve transplant outcomes in older patients.

Efficacy and Safety of Valproic Acid in Myelodysplastic Syndrome and Acute Myeloid Leukemia; a Narrative Review

Loads of new therapeutic regimes have been turned up to manage Myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), particularly in elderly patients who are unfit for intensive chemotherapy. Despite accumulating research, the best MDS and AML management approach is indeterminate. Myelodysplastic syndrome implies a group of various hematopoietic stem cell disorders that may progress to acute myeloid leukemia. These disorders are more frequent in older adults. To the high rate of morbidity and abundant toxicities related to the therapeutic approaches, also, the treatment would be challenging. The clinical effectiveness of valproic acid, a histone deacetylase inhibitor, in MDS and AML patients is unknown, even though it has demonstrated positive activities to promote differentiation and apoptosis in cancer cells. We investigated the clinical research on the effects of valproic acid in conjunction with various drugs, including low-dose cytarabine, all-trans retinoic acid, DNA-hypomethylating agents, hydrazine, and theophylline. We conclude that VPA is a safe and effective treatment option for MDS and AML patients, particularly when used in conjunction with all-trans retinoic acid, DNA-hypomethylating drugs, and hydralazine. However, more randomized clinical studies are required to identify an ideal regimen.

Updates on risk stratification and management of lower-risk myelodysplastic syndromes/neoplasms

The majority of lower-risk myelodysplastic syndromes/neoplasms patients present with anemia. Historically, these patients were treated with erythropoiesis-stimulating agents (ESA), with modest responses. A subset of these patients with del(5q) may do better with lenalidomide. Recently, in randomized trials, luspatercept has shown better responses compared with ESAs in treatment-naive patients and imetelstat in patients refractory to ESAs. Other evaluated novel compounds (fostamatinib, H3B-880, roxadustat, pyruvate kinase receptor activator) have not yet shown meaningful efficacy. More needs to be done to improve outcomes; in pursuance of this, participation in clinical trials evaluating novel therapies should be encouraged. While lower-risk myelodysplastic syndromes/neoplasms tend to have an indolent course, a subset of them has a dismal prognosis. Improving prognostication and serial monitoring will help in identifying high-risk patients for appropriate management.

Transplantation Referral Patterns for Patients with Newly Diagnosed Higher-Risk Myelodysplastic Syndromes and Acute Myeloid Leukemia at Academic and Community Sites in the Connect® Myeloid Disease Registry: Potential Barriers to Care

Hematopoietic stem cell transplantation (HCT) is indicated for patients with higher-risk (HR) myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Age, performance status, patient frailty, comorbidities, and nonclinical factors (eg, cost, distance to site) are all recognized as important clinical factors that can influence HCT referral patterns and patient outcomes; however, the proportion of eligible patients referred for HCT in routine clinical practice is largely unknown. This study aimed to assess patterns of consideration for HCT among patients with HR-MDS and AML enrolled in the Connect® Myeloid Disease Registry at community/government (CO/GOV)- or academic (AC)-based sites, as well as to identify factors associated with rates of transplantation referral. We assessed patterns of consideration for and completion of HCT in patients with HR-MDS and AML enrolled between December 12, 2013, and March 6, 2020, in the Connect Myeloid Disease Registry at 164 CO/GOV and AC sites. Registry sites recorded whether patients were considered for transplantation at baseline and at each follow-up visit. The following answers were possible: "considered potentially eligible," "not considered potentially eligible," or "not assessed." Sites also recorded whether patients subsequently underwent HCT at each follow-up visit. Rates of consideration for HCT between CO/GOV and AC sites were compared using multivariable logistic regression analysis with covariates for age and comorbidity. Among the 778 patients with HR-MDS or AML enrolled in the Connect Myeloid Disease Registry, patients at CO/GOV sites were less likely to be considered potentially eligible for HCT than patients at AC sites (27.9% versus 43.9%; P < .0001). Multivariable logistic regression analysis with factors for age (<65 versus ≥65 years) and ACE-27 comorbidity grade (<2 versus ≥2) showed that patients at CO/GOV sites were significantly less likely than those at AC sites to be considered potentially eligible for HCT (odds ratio, 1.6, 95% confidence interval, 1.1 to 2.4; P = .0155). Among patients considered eligible for HCT, 45.1% (65 of 144) of those at CO/GOV sites and 35.7% (41 of 115) of those at AC sites underwent transplantation (P = .12). Approximately one-half of all patients at CO/GOV (50.1%) and AC (45.4%) sites were not considered potentially eligible for HCT; the most common reasons were age at CO/GOV sites (71.5%) and comorbidities at AC sites (52.1%). Across all sites, 17.4% of patients were reported as not assessed (and thus not considered) for HCT by their treating physician (20.7% at CO/GOV sites and 10.7% at AC sites; P = .0005). These findings suggest that many patients with HR-MDS and AML who may be candidates for HCT are not receiving assessment or consideration for transplantation in clinical practice. In addition, treatment at CO/GOV sites and age remain significant barriers to ensuring that all potentially eligible patients are assessed for HCT.

Management of Patients with Lower-Risk Myelodysplastic Neoplasms (MDS)

Myelodysplastic neoplasms (MDS) are a heterogenous group of clonal hematologic disorders characterized by morphologic dysplasia, ineffective hematopoiesis, and cytopenia. In the past year, the classification of MDS has been updated in the 5th edition of the World Health Organization (WHO) Classification of Haematolymphoid Tumours and the International Consensus Classification (ICC) of Myeloid Neoplasms and Acute Leukemia with incorporation of morphologic, clinical, and genomic data. Furthermore, the more comprehensive International Prognostic Scoring System-Molecular (IPSS-M) allows for improved risk stratification and prognostication. These three developments allow for more tailored therapeutic decision-making in view of the expanding treatment options in MDS. For patients with lower risk MDS, treatment is aimed at improving cytopenias, usually anemia. The recent approval of luspatercept and decitabine/cedazuridine have added on to the current armamentarium of erythropoietic stimulating agents and lenalidomide (for MDS with isolated deletion 5q). Several newer agents are being evaluated in phase 3 clinical trials for this group of patients, such as imetelstat and oral azacitidine. This review provides a summary of the classification systems, the prognostic scores and clinical management of patients with lower risk MDS.

The Management of Low-Risk Myelodysplastic Syndromes-Current Standards and Recent Advances

ABSTRACT

The myelodysplastic syndromes (MDSs) are a heterogeneous group of hematologic neoplasms with varied natural histories and prognoses. Specific to this review, treatment of low-risk MDS most often focuses on improving quality of life by correcting cytopenias, as opposed to urgent disease modification to avoid acute myeloid leukemia. These treatments include transfusion support with iron chelation when necessary, growth factors including novel maturation agents such as luspatercept, lenalidomide for del(5q) disease, and, increasingly, low-dose hypomethylating agents. Recent advances in the understanding of the genetic lesions that drive MDS have prompted a reassessment of how low-risk disease is defined and helped to identify a subset of low-risk MDS patients who may benefit from a more aggressive treatment paradigm, including hematopoietic stem cell transplantation.

Allogeneic transplantation of bone marrow versus peripheral blood stem cells from HLA-identical relatives in patients with myelodysplastic syndromes and oligoblastic acute myeloid leukemia: a propensity score analysis of a nationwide database

Bone marrow (BM) and granulocyte colony-stimulating factor-mobilized peripheral blood stem cells (PBSC) are used as grafts from HLA-identical-related donors for adults with myelodysplastic syndrome (MDS). To assess the impact of graft sources on post-transplant outcomes in MDS patients, we conducted a retrospective analysis of a nationwide database. A total of 247 and 280 patients underwent transplantation with BM and PBSC, respectively. The inverse probability of treatment weighting (IPTW) methods revealed that overall survival (OS) was comparable between BM and PBSC (P = .129), but PBSC transplantation was associated with worse graft-versus-host disease (GVHD)-free/relapse-free survival (GRFS) (hazard rate [HR], 1.24; 95% confidence intervals [CIs], 1.00-1.53; P = 0.049) and chronic GVHD-free and relapse-free survival (CRFS) (HR, 1.29; 95% CIs, 1.13-1.73; P = 0.002) than BM transplantation. In the propensity score matched cohort (BM, n = 216; PBSC, n = 216), no significant differences were observed in OS and relapse; 3-year OS rates were 64.7% and 60.0% (P = 0.107), while 3-year relapse rates were 27.1% and 23.5% (P = 0.255) in BM and PBSC, respectively. Three-year GRFS rates (36.6% vs. 29.2%; P = 0.006), CRFS rate (37.7% vs. 32.5%; P = 0.003), and non-relapse mortality rates (13.9% vs. 21.1%; P = 0.020) were better in BM than in PBSC. The present study showed that BM transplantation provides a comparable survival benefit with PBSC transplantation and did not identify an enhanced graft-versus-MDS effect to reduce the incidence of relapse in PBSC transplantation.

SOHO State of the Art Updates and Next Questions: Treatment of Lower Risk Myelodysplastic Syndromes

MDS is a clonal stem cell neoplasm with a spectrum from lower risk disease to short term life threatening higher risk disease. The disease risk is dictated by clinical and molecular features. Majority of MDS patients including lower risk disease unfortunately succumb from disease related complications namely cytopenia. While cytopenias may be mild early upon diagnosis and can be surveilled, ultimately treatment is required. Anemia is the hall mark of disease and most common indication to treat in lower risk MDS. Erythroid stimulating agents are used in the first line setting. Treatment can be a personalized approach as in select patient such as patients with del(5q) and those with ringed sideroblasts, lenalidomide, and luspatercept can be extremely effective respectively at improving cytopenias. Younger patients and hypoplastic MDS have also shown and improved response to immunosuppressive therapy. Hypomethylating agents can be option for patients with higher risk features or thrombocytopenia/neutropenia. Refractory cytopenias still poses frustration as options are limited and there is need to add more treatments to our armamentarium.

Characterization and Function of Cryopreserved Bone Marrow from Deceased Organ Donors: A Potential Viable Alternative Graft Source

Despite the readily available graft sources for allogeneic hematopoietic cell transplantation (alloHCT), a significant unmet need remains in the timely provision of suitable unrelated donor grafts. This shortage is related to the rarity of certain HLA alleles in the donor pool, nonclearance of donors owing to infectious disease or general health status, and prolonged graft procurement and processing times. An alternative hematopoietic progenitor cell (HPC) graft source obtained from the vertebral bodies (VBs) of deceased organ donors could alleviate many of the obstacles associated with using grafts from healthy living donors or umbilical cord blood (UCB). Deceased organ donor-derived bone marrow (BM) can be preemptively screened, cryogenically banked for on-demand use, and made available in adequate cell doses for HCT. We have developed a good manufacturing practice (GMP)-compliant process to recover and cryogenically bank VB-derived HPCs from deceased organ donor (OD) BM. Here we present results from an analysis of HPCs from BM obtained from 250 deceased donors to identify any substantial difference in composition or quality compared with HPCs from BM aspirated from the iliac crests of healthy living donors. BM from deceased donor VBs was processed in a central GMP facility and packaged for cryopreservation in 5% DMSO/2.5% human serum albumin. BM aspirated from living donor iliac crests was obtained and used for comparison. A portion of each specimen was analyzed before and after cryopreservation by flow cytometry and colony-forming unit potential. Bone marrow chimerism potential was assessed in irradiated immunocompromised NSG mice. Analysis of variance with Bonferroni correction for multiple comparisons was used to determine how cryopreservation affects BM cells and to evaluate indicators of successful engraftment of BM cells into irradiated murine models. The t test (with 95% confidence intervals [CIs]) was used to compare cells from deceased donors and living donors. A final dataset of complete clinical and matched laboratory data from 226 cryopreserved samples was used in linear regressions to predict outcomes of BM HPC processing. When compared before and after cryopreservation, OD-derived BM HPCs were found to be stable, with CD34+ cells maintaining high viability and function after thawing. The yield from a single donor is sufficient for transplantation of an average of 1.6 patients (range, 1.2 to 7.5). CD34+ cells from OD-derived HPCs from BM productively engrafted sublethally irradiated immunocompromised mouse BM (>44% and >67% chimerism at 8 and 16 weeks, respectively). Flow cytometry and secondary transplantation confirmed that OD HPCs from BM is composed of long-term engrafting CD34+CD38-CD45RA-CD90+CD49f+ HSCs. Linear regression identified no meaningful predictive associations between selected donor-related characteristics and OD BM HPC quality or yield. Collectively, these data demonstrate that cryopreserved BM HPCs from deceased organ donors is potent and functionally equivalent to living donor BM HPCs and is a viable on-demand graft source for clinical HCT. Prospective clinical trials will soon commence in collaboration with the Center for International Blood and Marrow Research to assess the feasibility, safety, and efficacy of Ossium HPCs from BM (ClinicalTrials.gov identifier NCT05068401).

Hematopoietic Cell Transplantation in the Management of Myelodysplastic Syndrome: An Evidence-Based Review from the American Society for Transplantation and Cellular Therapy Committee on Practice Guidelines

The sole curative therapy for myelodysplastic syndrome (MDS) is allogeneic hematopoietic cell transplantation (HCT). Here this therapeutic modality is reviewed and critically evaluated in the context of the evidence. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the recommendations. A panel of MDS experts comprising transplantation and nontransplantation physicians developed consensus treatment recommendations. This review summarizes the standard MDS indications for HCT and addresses areas of controversy. Recent prospective trials have confirmed that allogeneic HCT confers survival benefits in patients with advanced or high-risk MDS compared with nontransplantation approaches, and the use of HCT is increasing in older patients with good performance status. However, patients with high-risk cytogenetic or molecular mutations remain at high risk for relapse. It is unknown whether administration of novel therapies before or after transplantation may decrease the risk of disease relapse in selected populations. Ongoing and future studies will investigate revised approaches to disease risk stratification, patient selection, and post-transplantation approaches to optimize allogeneic HCT outcomes for patients with MDS.

Decision analysis of allogeneic bone marrow transplantation versus immunosuppressive therapy for young adult patients with aplastic anemia

BACKGROUND

Allogeneic bone marrow transplantation (BMT) from an HLA-matched sibling donor is recommended as an initial treatment for young patients. However, immunosuppressive therapy (IST) with cyclosporine and anti-thymocyte globulin may be a viable option even when an HLA-identical sibling donor is available.

METHODS

We constructed a Markov model to simulate the 10-year clinical course of patients aged 21-40 years with newly diagnosed severe aplastic anemia. Immediate BMT and IST were compared as an initial treatment assuming the availability of an HLA-identical sibling donor. Transition probabilities after treatment were determined based on a registry data analysis for BMT and a long-term prospective study for IST.

RESULTS

Quality-adjusted life years (QALYs) after treatment selection were 6.77 for BMT and 6.74 for IST. One-way sensitivity analysis revealed that the utility for being alive without GVHD after BMT, that for being alive with partial response after IST, and the response rate after initial IST strongly affected the results.

CONCLUSIONS

BMT and IST produced similar QALY for young patients with severe aplastic anemia. An estimation of the response rate to the initial IST may enable an individualized comparison between BMT and IST.

Appropriate pre-transplant strategy for patients with myelodysplastic syndromes receiving allogeneic haematopoietic stem cell transplantation after myeloablative conditioning

Purpose

Appropriate pre-transplant strategies in patients with myelodysplastic syndromes (MDS) remain challenging. We sought to assess the effect of different pre-transplant therapies and transplantation interval times on patient prognosis.

Methods

We retrospectively analysed clinical data for 371 consecutive MDS patients after myeloablative transplantation between 2007 and 2019.

Results

The median age of the patients was 38 years (range, 12-64 years). A total of 114 patients (31%) received supportive care (SC), 108 (29%) hypomethylating agents (HMAs), and 149 (40%) chemotherapy-based therapy before transplantation. In patients who received HMA or SC, there was no significant difference in overall survival (OS; P=0.151) or relapse-free survival (RFS; P=0.330), except that HMA-treated patients had a lower rate of non-relapse mortality (5-year NRM: 18% vs. 32%, P=0.035). However, compared with patients who received HMA, those who received chemotherapy-based therapy had a lower 5-year OS rate (56% vs. 69%, P=0.020) and a slightly higher 5-year NRM rate (28% vs. 18%, P=0.067). Compared to the delayed transplant group (transplant interval ≥6 months), the early transplant group (transplant interval <6 months) had a superior 5-year OS (66% vs. 51%, P=0.001) and a lower 5-year cumulative incidence of NRM (22% vs. 36%, P=0.001).

Conclusion

The findings of the study indicate that receiving an appropriate pre-transplant strategy (SC/HMA + <6 months) significantly improves OS and decreases NRM in MDS patients after myeloablative transplantation.

SOHO State of the Art and Next Questions: Treatment of Higher-Risk Myelodysplastic Syndromes

Higher-risk myelodysplastic syndromes (MDS) carry a dismal prognosis with rapid disease progression, disease-related complications that impact quality of life, high risk of transformation to acute myeloid leukemia (AML), and poor long-term survival. Higher-risk disease is determined by a number of factors including the depth and type of cytopenias, percentage of myeloblasts occupying the bone marrow, cytogenetic abnormalities, and increasingly also by the presence of higher-risk molecular alterations. In addition to disease characteristics, a patient's performance status and degree of co-morbidity strongly influence treatment decisions and clinical outcomes. A critical first step in the management of patients with higher-risk MDS is evaluating eligibility for allogeneic hematopoietic stem cell transplant (HCT), which currently remains the only curative therapy, and is available to an ever-increasing number of patients. Outside of stem cell transplant, treatment with hypomethylating agent chemotherapy, azacitidine or decitabine, remains the cornerstone of therapy with improvements in overall survival and reduced transformation to AML; however, these approaches are palliative in nature and outcomes remain very poor overall. With a deepening understanding of disease pathophysiology has come a burgeoning array of novel targeted therapies that are currently in pre-clinical and early phase clinical trials offering hope for new treatment options for this malignancy.

Role of allogeneic transplantation in chronic myelomonocytic leukemia: an international collaborative analysis

To determine the survival benefit of allogeneic hematopoietic cell transplantation (allo-HCT) in chronic myelomonocytic leukemias (CMML), we assembled a retrospective cohort of CMML patients 18-70 years old diagnosed between 2000 and 2014 from an international CMML dataset (n = 730) and the EBMT registry (n = 384). The prognostic impact of allo-HCT was analyzed through univariable and multivariable time-dependent models and with a multistate model, accounting for age, sex, CMML prognostic scoring system (low or intermediate-1 grouped as lower-risk, intermediate-2 or high as higher-risk) at diagnosis, and AML transformation. In univariable analysis, lower-risk CMMLs had a 5-year overall survival (OS) of 20% with allo-HCT vs 42% without allo-HCT (P < .001). In higher-risk patients, 5-year OS was 27% with allo-HCT vs 15% without allo-HCT (P = .13). With multistate models, performing allo-HCT before AML transformation reduced OS in patients with lower-risk CMML, and a survival benefit was predicted for men with higher-risk CMML. In a multivariable analysis of lower-risk patients, performing allo-HCT before transformation to AML significantly increased the risk of death within 2 years of transplantation (hazard ratio [HR], 3.19; P < .001), with no significant change in long-term survival beyond this time point (HR, 0.98; P = .92). In higher-risk patients, allo-HCT significantly increased the risk of death in the first 2 years after transplant (HR 1.46; P = .01) but not beyond (HR, 0.60; P = .09). Performing allo-HCT before AML transformation decreases life expectancy in lower-risk patients but may be considered in higher-risk patients.

Diagnosis and Treatment of Myelodysplastic Syndromes: A Review

IMPORTANCE

Myelodysplastic neoplasms (MDS), formerly known as myelodysplastic syndromes, are clonal hematopoietic malignancies that cause morphologic bone marrow dysplasia along with anemia, neutropenia, or thrombocytopenia. MDS are associated with an increased risk of acute myeloid leukemia (AML). The yearly incidence of MDS is approximately 4 per 100 000 people in the United States and is higher among patients with advanced age.

OBSERVATIONS

MDS are characterized by reduced numbers of peripheral blood cells, an increased risk of acute myeloid leukemia transformation, and reduced survival. The median age at diagnosis is approximately 70 years, and the yearly incidence rate increases to 25 per 100 000 in people aged 65 years and older. Risk factors associated with MDS include older age and prior exposures to toxins such as chemotherapy or radiation therapy. MDS are more common in men compared with women (with yearly incidence rates of approximately 5.4 vs 2.9 per 100 000). MDS typically has an insidious presentation, consisting of signs and symptoms associated with anemia, thrombocytopenia, and neutropenia. MDS can be categorized into subtypes that are associated with lower or higher risk for acute myeloid leukemia transformation and that help with therapy selection. Patients with lower-risk MDS have a median survival of approximately 3 to 10 years, whereas patients with higher-risk disease have a median survival of less than 3 years. Therapy for lower-risk MDS is selected based on whether the primary clinical characteristic is anemia, thrombocytopenia, or neutropenia. Management focuses on treating symptoms and reducing the number of required transfusions in patients with low-risk disease. For patients with lower-risk MDS, erythropoiesis stimulating agents, such as recombinant humanized erythropoietin or the longer-acting erythropoietin, darbepoetin alfa, can improve anemia in 15% to 40% of patients for a median of 8 to 23 months. For those with higher-risk MDS, hypomethylating agents such as azacitidine, decitabine, or decitabine/cedazuridine are first-line therapy. Hematopoietic cell transplantation is considered for higher-risk patients and represents the only potential cure.

CONCLUSIONS AND RELEVANCE

MDS are diagnosed in approximately 4 per 100 000 people in the United States and are associated with a 5-year survival rate of approximately 37%. Treatments are tailored to the patient's disease characteristics and comorbidities and range from supportive care with or without erythropoiesis-stimulating agents for patients with low-risk MDS to hypomethylating agents, such as azacitidine or decitabine, for patients with higher-risk MDS. Hematopoietic cell transplantation is potentially curative and should be considered for patients with higher-risk MDS at the time of diagnosis.

Outcome of therapy-related myelodysplastic syndrome and oligoblastic acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation: A propensity score matched analysis

Therapy-related myelodysplastic syndromes (t-MDS) are generally progressive and associated with poorer outcomes than de novo MDS (d-MDS). To evaluate the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for t-MDS, we conducted a propensity score matched-pair analysis of patients with t-MDS and d-MDS using a nationwide database. A total of 178 patients with t-MDS underwent allo-HSCT between 2001 and 2018, and 178 out of 3,123 patients with d-MDS were selected. The probability of 3-year overall survival rate was 40.0% and 50.0% in the t-MDS and d-MDS groups, respectively (P=0.032). The 3-year transplant-related mortality was 30.9% and 19.0% in the t-MDS and d-MDS groups, respectively (P=0.005). The 3-year cumulative incidence of relapse was 32.8% and 33.0% in the t-MDS and d-MDS groups, respectively (P=0.983). A multivariate analysis identified four adverse factors for overall survival in the t-MDS group: age ≥55 years (hazard ratio [HR], 2.09; 95% CI, 1.11-3.94; P=0.023), the poor cytogenetic risk group (HR, 2.19; 95% CI, 1.40-4.19; P=0.019), performance status at allo-HSCT 2-4 (HR, 2.14; 95% CI, 1.19-3.86; P=0.011), and a shorter interval from diagnosis to transplantation (<8 months) (HR, 1.61; 95% CI, 1.00-2.57; P=0.048). The most frequent cause of transplant-related death was the infectious complications (21.6%) in t-MDS group and organ failure (12.5%) in d-MDS group. In conclusion, allo-HSCT potentially provides long-term remission in patients with t-MDS; however, further efforts to reduce transplant-related death are needed. This article is protected by copyright. All rights reserved.

Chronic myelomonocytic leukemia: 2022 update on diagnosis, risk stratification, and management

DISEASE OVERVIEW

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic stem cell disorder with overlapping features of myelodysplastic syndromes and myeloproliferative neoplasms, with an inherent risk for leukemic transformation (~15% over 3-5 years).

DIAGNOSIS

Diagnosis is based on the presence of sustained (>3 months) peripheral blood monocytosis (≥1 × 10⁹ /L; monocytes ≥10%), usually with accompanying bone marrow dysplasia. Clonal cytogenetic abnormalities occur in ~30% of patients, while >90% have somatic gene mutations. Mutations involving TET2 (~60%), SRSF2 (~50%), ASXL1 (~40%), and the oncogenic RAS pathway (~30%) are frequent, while the presence of ASXL1 and DNMT3A mutations and the absence of TET2 mutations negatively impact overall survival.

RISK-STRATIFICATION

Molecularly integrated prognostic models include the Groupe Français des Myélodysplasies, Mayo Molecular Model (MMM), and the CMML specific prognostic model. Risk factors incorporated into the MMM include presence of truncating ASXL1 mutations, absolute monocyte count >10 × 10⁹ /L, hemoglobin <10 g/dL, platelet count <100 × 10⁹ /L, and the presence of circulating immature myeloid cells. The MMM stratifies CMML patients into four groups: high (≥3 risk factors), intermediate-2 (2 risk factors), intermediate-1 (1 risk factor), and low (no risk factors), with median survivals of 16, 31, 59, and 97 months, respectively.

RISK-ADAPTED THERAPY

Hypomethylating agents such as 5-azacitidine and decitabine are commonly used, with overall response rates of ~40%-50% and complete remission rates of ~7%-17%; with no impact on mutational allele burdens. Allogeneic stem cell transplant is the only potentially curative option but is associated with significant morbidity and mortality.

How low risk are low risk myelodysplastic syndromes?

INTRODUCTION

Risk stratification is crucial to the appropriate management of many diseases, but in patients with myelodysplastic syndromes (MDS), for whom expected survival can vary greatly, accurate disease prognostication is especially important. This is further supported by a relative lack of therapies in MDS, and thus we must prognosticate carefully and accurately. Currently, patients with MDS are often grouped into higher-risk (HR) versus lower-risk (LR) disease using clinical prognostic scoring systems, but these systems have limitations.

AREAS COVERED

The authors reviewed the literature on diagnostics, prognostics, therapeutics and outcomes in MDS. Factors such as disease etiology, specific clinical characteristics, or molecular genetic information not captured in the international prognostic scoring system revised IPSS-R can alter risk stratification, and identify a subset of LR-MDS patients who actually behave more like HR-MDS.

EXPERT OPINION

This review will describe the current identification and management of patients with LR MDS disease whose condition is likely to behave in a less favorable manner than predicted by the IPSS-R. The authors comment on clinical and molecular features which are believe to upstage a patient from lower to higher risk disease.

Lower risk but high risk

Risk stratification is crucial to the appropriate management of most cancers, but in patients with myelodysplastic syndromes (MDS), for whom expected survival can vary from a few months to more than a decade, accurate disease prognostication is especially important. Currently, patients with MDS are often grouped into higher-risk (HR) vs lower-risk (LR) disease using clinical prognostic scoring systems, but these systems have limitations. Factors such as molecular genetic information or disease characteristics not captured in the International Prognostic Scoring System-Revised (IPSS-R) can alter risk stratification and identify a subset of patients with LR-MDS who actually behave more like those with HR-MDS. This review describes the current identification and management of patients with LR-MDS whose condition is likely to behave in a less favorable manner than predicted by the IPSS-R.

Hypomethylating Agents and FLT3 Inhibitors As Maintenance Treatment for Acute Myeloid Leukemia and Myelodysplastic Syndrome After Allogeneic Hematopoietic Stem Cell Transplantation-A Systematic Review and Meta-Analysis

BACKGROUND

Disease relapse remains the major cause of death among patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) who receive an allogeneic hematopoietic cell transplant (allo-HCT). Maintenance treatment with FLT3 inhibitors and hypomethylating agents (HMA) has been studied in various clinical trials with mixed results.

OBJECTIVE

To synthesize the current evidence on the efficacy and safety of FLT3 inhibitors and HMA for maintenance therapy after allo-HCT in AML and MDS.

METHODS

For this systematic review and meta-analysis Cochrane Library, Google Scholar, Ovid Medline, Ovid Embase, PubMed, Scopus, and Web of Science Core Collection were searched from inception to March 2021 for studies on maintenance therapies after allo-HCT in AML and MDS. Studies were excluded if they were reviews, commentaries, case series with <5 patients, or basic research articles, not published in English, not on post-allo-HCT maintenance with FLT3 inhibitors or HMA in AML or MDS, or if they were clinical trials without published results or duplicate publications from the same patient cohort. Studies with insufficient reporting of the primary endpoint (2-year overall survival [OS]) and studies using FLT3 inhibitors or HMA for pre-emptive treatment of imminent relapse based on positive measurable residual disease testing were excluded. Random-effects models were used to pool response rates for the primary outcome of 2-year OS. Hazard ratios (HR) for death and relapse were calculated for studies that included a control group. Rates of relapse-free survival (RFS), non-relapse mortality, and acute and chronic graft-versus-host-disease (GVHD) were studied as secondary endpoints. Downs and Black checklist and risk of bias assessments were used to gauge the quality of individual studies. The study protocol has been registered on PROSPERO (CRD42020187298).

RESULTS

Our search strategy identified 5559 studies. Twenty-one studies with a total of 809 patients were included in the meta-analysis. The 2-year OS rates were 81.7% (95% confidence interval [CI], 73.8%-87.7%) and 65.7% (95% CI, 55.1%-74.9%) among patients treated with FLT3 inhibitors and HMA, respectively. In sensitivity analyses restricted to studies that included a control group, maintenance therapy with FLT3 inhibitors (HR for death = 0.41; 95% CI, 0.26-0.62) or HMA (HR = 0.45; 95% CI, 0.31-0.66) appeared superior to no maintenance therapy. The 2-year RFS rates were 79.8% (95% CI, 75.0%-83.9%) and 62.4% (95% CI, 50.6%-72.9%) among patients treated with FLT3 inhibitors and HMA, respectively. Rates of any grade acute and chronic GVHD were 33.1% (95% CI, 25.4%-41.8%; grade 3/4: 16.5%) and 42.5% (95% CI, 26.3%-60.4%) among FLT3 inhibitor and 42.7% (95% CI, 33.5%-52.4%; grade 3/4: 8.1%) and 41.5% (95% CI, 32.0%-51.6%) among HMA-treated patients, respectively.

CONCLUSION

Maintenance therapy with either FLT3 inhibitors or HMA after allo-HCT can lead to prolonged and improved OS and RFS with a favorable safety profile. Additional studies are needed to define the optimal duration of treatment, the role of measurable residual disease status, and transplant characteristics in patient selection.

Biologic Assignment Trial of Reduced-Intensity Hematopoietic Cell Transplantation Based on Donor Availability in Patients 50-75 Years of Age With Advanced Myelodysplastic Syndrome

PURPOSE

Allogeneic hematopoietic cell transplantation (HCT) is the only potentially curative therapy for myelodysplastic syndromes (MDS), although it is infrequently offered to older patients. The relative benefits of HCT over non-HCT therapy in older patients with higher-risk MDS have not been defined.

METHODS

We conducted a multicenter biologic assignment trial comparing reduced-intensity HCT to hypomethylating therapy or best supportive care in subjects 50-75 years of age with intermediate-2 or high-risk de novo MDS. The primary outcome was overall survival probability at 3 years. Between January 2014 and November 2018, we enrolled 384 subjects at 34 centers. Subjects were assigned to the Donor or No-Donor arms according to the availability of a matched donor within 90 days of study registration.

RESULTS

The median follow-up time for surviving subjects was 34.2 months (range: 2.3-38 months) in the Donor arm and 26.9 months (range: 2.4-37.2 months) in the No-Donor arm. In an intention-to-treat analysis, the adjusted overall survival rate at 3 years in the Donor arm was 47.9% (95% CI, 41.3 to 54.1) compared with 26.6% (95% CI, 18.4 to 35.6) in the No-Donor arm (P = .0001) with an absolute difference of 21.3% (95% CI, 10.2 to 31.8). Leukemia-free survival at 3 years was greater in the Donor arm (35.8%; 95% CI, 29.8 to 41.8) compared with the No-Donor arm (20.6%; 95% CI, 13.3 to 29.1; P = .003). The survival benefit was seen across all subgroups examined.

CONCLUSION

We observed a significant survival advantage in older subjects with higher-risk MDS who have a matched donor identified and underwent reduced-intensity HCT, when compared with those without a donor. HCT should be included as an integral part of MDS management plans in fit older adults with higher-risk MDS.

Biology and clinical management of hypoplastic MDS: MDS as a bone marrow failure syndrome

Hypoplastic MDS is a subset of MDS characterized by marrow hypocellularity diagnosed in 10-15% of MDS patients. The pathogenesis of this disease shares features of aplastic anemia with activation of the effector T cells against hematopoietic stem and progenitor cells and high-risk MDS with acquisition of somatic mutations that provide survival and growth advantage of these cells in the inflammatory bone marrow microenvironment. Clonal evolution in hypoplastic MDS may be associated with accumulation of DNA damage and progression to AML while clonal hematopoiesis in aplastic anemia is strongly related to immune escape of the hematopoietic cells. Distinction of hypoplastic MDS from other acquired and inherited bone marrow failure syndromes is frequently challenging but it is critical for the appropriate clinical management of the patients. Treatment with immunosuppression is an important component of the clinical approach to patients with hypoplastic MDS while hypomethylating agents and early allogeneic bone marrow transplantation are also considerations in some patients. In this review, we summarize the current literature on the biology of hypoplastic MDS, the differences between this disease and other bone marrow failure syndromes, and the treatment algorithm for patients with this subtype of MDS.

Management of the Older Patient with Myelodysplastic Syndrome

No two diagnoses of myelodysplastic syndrome are genuinely alike, owing to differing and dynamic mutational topography and epigenetic aberrancy. Consequently, no two patients with myelodysplastic syndrome are identical and disease-specific and patient-specific factors are considered in formulating the optimal treatment, which includes few that are disease modifying. Age itself should not be an absolute contraindication to therapy, including intensive therapy such as allogeneic hematopoietic stem cell transplantation, which is the only curative therapy. However, age associates with an increased prevalence of frailty and comorbidities that must be considered and may preclude a path to cure. Palliative therapies are the mainstay for many patients with myelodysplastic syndrome, which is a disease of older adults with the majority of patients diagnosed at age ≥ 75 years. The older patient requires heightened attention to end organ function/reserve and drug-drug interactions as well as insurance, income, cost, and socioeconomic and psychosocial issues that influence management. Many prior studies have included relatively younger populations or have not specifically performed high-quality subgroup analyses of older patients. In this review, we discuss the available standard-of-care therapies for myelodysplastic syndrome as they specifically relate to the older population and assess the emerging therapeutics that may further the pursuit for personalized treatment and improve both the outcomes and quality of life of the older patient with myelodysplastic syndrome.

Allogeneic hematopoietic cell transplantation with non-myeloablative conditioning for patients with hematologic malignancies: Improved outcomes over two decades

We have used a non-myeloablative conditioning regimen for allogeneic hematopoietic cell transplantation for the past 20 years. During that period, changes in clinical practice have been aimed at reducing morbidity and mortality from infections, organ toxicity, and graft-versus-host disease. We hypothesized that improvements in clinical practice led to better transplantation outcomes over time. From 1997–2017, 1,720 patients with hematologic malignancies received low-dose total body irradiation ± fludarabine or clofarabine before transplantation from HLAmatched sibling or unrelated donors, followed by mycophenolate mofetil and a calcineurin inhibitor ± sirolimus. We compared outcomes in three cohorts by year of transplantation: 1997–2003 (n=562), 2004–2009 (n =594), and 2010–2017 (n=564). The proportion of patients ≥60 years old increased from 27% in 1997–2003 to 56% in 2010–2017, and with scores from the Hematopoietic Cell Transplantation Comorbidity Index of ≥3 increased from 25% in 1997–2003 to 45% in 2010–2017. Use of unrelated donors increased from 34% in 1997–2003 to 65% in 2010–2017. When outcomes from 2004–2009 and 2010–2017 were compared to 1997–2003, improvements were noted in overall survival (P=0.0001 for 2004–2009 and P≤0.0001 for 2010–2017), progression-free survival (P=0.002 for 2004–2009 and P<0.0001 for 2010–2017), non-relapse mortality (P<0.0001 for 2004– 2009 and P<0.0001 for 2010–2017), and in rates of grades 2–4 acute and chronic graft-versus-host disease. For patients with hematologic malignancies who underwent transplantation with non-myeloablative conditioning, outcomes have improved during the past two decades. Trials reported are registered under clinicaltrials gov. Identifiers: NCT00003145, NCT00003196, 005803, NCT00006251, NCT00014235, NCT00027820, NCT00031655, NCT00036738, NCT00045435, NCT00052546, NCT00060424, NCT00075478, NCT00078858, NCT00089011, NCT00104858, NCT00105001, NCT00110058, NCT00397813, NCT00793572, NCT01231412, NCT01252667, NCT01527045.

Erythroid nuclear dysplasia is associated with inferior outcomes for patients with myelodysplastic syndrome undergoing allogeneic hematopoietic cell transplantation

Disease burden prior to hematopoietic cell transplantation (HCT) is difficult to assess in myelodysplastic syndrome (MDS), particularly in patients without excess blasts. We assessed whether morphologic dysplasia at the time of transplant can be a metric of disease burden that is associated with post-transplant outcomes in MDS patients. We identified 84 MDS patients undergoing allogeneic HCT at our institution between 2010 and 2017 who received a bone marrow evaluation immediately prior to HCT. Dysplasia was independently determined by two hematopathologists blinded to existing pathology reports. Erythroid nuclear dysplasia, but not megakaryocytic or myeloid, was associated with post-HCT outcomes. Presence compared to absence of erythroid nuclear dysplasia was associated with lower 2-year progression-free survival (PFS; 34 % vs 62 %, p = 0.0495) and 2-year overall survival (OS; 34 % vs 62 %, p = 0.042). In a multivariate analysis including age, IPSS-R at the time of transplant, pre-HCT therapy, and donor type as covariates, erythroid nuclear dysplasia remained associated with lower PFS (HR 2.6, p = 0.036) and OS (HR 2.7, p = 0.028). Dysplasia assessment prior to transplant may serve as an estimate of disease burden in MDS and identify high-risk patients who merit additional therapies pre- or post-transplant.

Current Therapy of the Patients with MDS: Walking towards Personalized Therapy

Myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis, dysplasia and peripheral cytopenias. Nowadays, MDS therapy is selected based on risk. The goals of therapy are different in low-risk and high-risk patients. In low-risk MDS, the goal is to decrease transfusion needs and to increase the quality of life. Currently, available drugs for newly diagnosed low-risk MDS include growth factor support, lenalidomide and immunosuppressive therapy. Additionally, luspatercept has recently been added to treat patients with MDS with ring sideroblasts, who are not candidates or have lost the response to erythropoiesis-stimulating agents. Treatment of high-risk patients is aimed to improve survival. To date, the only currently approved treatments are hypomethylating agents and allogeneic stem cell transplantation. However, the future for MDS patients is promising. In recent years, we are witnessing the emergence of multiple treatment combinations based on hypomethylating agents (pevonedistat, magrolimab, eprenetapopt, venetoclax) that have proven to be effective in MDS, even those with high-risk factors. Furthermore, the approval in the US of an oral hypomethylating agent opens the door to exclusively oral combinations for these patients and their consequent impact on the quality of life of these patients. Relapsed and refractory patients remain an unmet clinical need. We need more drugs and clinical trials for this profile of patients who have a dismal prognosis.

Impact of age, functional status, and comorbidities on quality of life and outcomes in elderly patients with AML: review

The incidence of acute myeloid leukemia increases with age, and more than half of AML patients are over 60 years old. Treating elderly AML patients presents several challenges and uncertainties, linked partly to disease characteristics and partly to the difficulty of establishing which patients could benefit from the best treatment. Although some elderly fit patients can receive intensive therapy, many of them are not treated and not enrolled in clinical trials. Yet supportive care is associated with significantly lower survival rates compared to intensive therapy or lower intensive therapy. A poorer prognosis in elderly patients is related to age, functional status, and comorbidities, combined with leukemia characteristics. Chronological age is not the best surrogate factor for selecting patients eligible for intensive chemotherapy. Scoring systems-including patient characteristics (ECOG, comorbidities) and disease characteristics (cytogenetics and molecular parameters)-designed to evaluate probabilities of response to treatment, morbidity, and survival may be used to balance the risk-benefit ratio for intensive therapy. A geriatric assessment (GA) to evaluate physical function, comorbidities, nutritional status, cognitive function, and social support could help identify the most vulnerable patients so that they can receive intensive therapy. A GA would also help take the necessary steps to improve tolerance to treatment. Evaluating markers of fitness and quality of life as part of clinical trials should be favored.

How old is too old for a transplant?

Allogeneic transplantation remains the most definitive curative option for patients with acute myeloid leukemia (AML). However, given the median age of diagnosis of AML in the late 60s, patients and clinicians have been reluctant to offer transplant to many in the older population. In this age group, AML presents with higher risk molecular and cytogenetic phenotype and patients' comorbidities, performance status, frailty and life views all impact the decision-making about whether to proceed with transplantation. Recent analyses suggest promising outcomes and thus acknowledgement of chronological age should be tempered with assessments of performance status, frailty, donor availability and careful balancing of a patient's wishes, life goals and understanding of the risks before restricting access of older patients to the curative potential of allotransplantation.

Myelodysplastic syndromes with ring sideroblasts (MDS-RS) and MDS/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T) - "2021 update on diagnosis, risk-stratification, and management"

DISEASE OVERVIEW

Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include myelodysplastic syndromes with RS (MDS-RS) and MDS/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T).

DIAGNOSIS

MDS-RS is a lower risk MDS, with single or multilineage dysplasia (MDS-RS-SLD/MLD), <5% bone marrow (BM) blasts, <1% peripheral blood blasts and ≥15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥450 × 10⁹ /L and large atypical megakaryocytes.

MUTATIONS AND KARYOTYPE

Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F (50%), DNMT3A, TET2 and ASXL1 mutations. Cytogenetic abnormalities are uncommon in both.

RISK STRATIFICATION

Most patients with MDS-RS-SLD are stratified into lower risk groups by the revised-IPSS. Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia (MPN). Both diseases are associated with a low risk of leukemic transformation.

TREATMENT

Anemia and iron overload are complications seen in both and are managed similar to lower risk MDS and MPN. Luspatercept, a first-in-class erythroid maturation agent is now approved for the management of anemia in patients with MDS-RS and MDS/MPN-RS-T. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs remains to be defined.

Asian Population Is More Prone to Develop High-Risk Myelodysplastic Syndrome, Concordantly with Their Propensity to Exhibit High-Risk Cytogenetic Aberrations

Simple Summary

The world population is genetically and environmentally diverse. In particular, genetic differences related to an ethnic factor may underlie differences in cancer phenotypic expression. Therefore, we compared the epidemiology, and the clinical, biological and genetic characteristics of myelodysplastic syndrome (MDS) between Asian and Western countries. Our results show substantial differences in the incidence and age of onset between Asian and Western MDS patients. A higher proportion of Asian MDS patients fall into the high- and very-high risk prognostic MDS groups. This finding is supported by the identification of a higher proportion of high-risk cytogenetic aberrations in Asian MDS patients. However, the survival rate is similar for Western and Asian MDS patients. Our findings may impact the clinical management as well as the strategy of clinical trials targeting those genetic aberrations and mutations depending on the world area where they are run.

Abstract

This study explores the hypothesis that genetic differences related to an ethnic factor may underlie differences in phenotypic expression of myelodysplastic syndrome (MDS). First, to identify clear ethnic differences, we systematically compared the epidemiology, and the clinical, biological and genetic characteristics of MDS between Asian and Western countries over the last 20 years. Asian MDS cases show a 2- to 4-fold lower incidence and a 10-year younger age of onset compared to the Western cases. A higher proportion of Western MDS patients fall into the very low- and low-risk categories while the intermediate, high and very high-risk groups are more represented in Asian MDS patients according to the Revised International Prognostic Scoring System. Next, we investigated whether differences in prognostic risk scores could find their origin in differential cytogenetic profiles. We found that 5q deletion (del(5q)) aberrations and mutations in TET2, SF3B1, SRSF2 and IDH1/2 are more frequently reported in Western MDS patients while trisomy 8, del(20q), U2AF1 and ETV6 mutations are more frequent in Asian MDS patients. Treatment approaches differ between Western and Asian countries owing to the above discrepancies, but the overall survival rate within each prognostic group is similar for Western and Asian MDS patients. Altogether, our study highlights greater risk MDS in Asians supported by their cytogenetic profile.

Splenectomy before allogeneic hematopoietic cell transplantation for myelofibrosis: A French nationwide study

The value of pretransplant splenectomy in patients with myelofibrosis (MF) is subject to debate, since the procedure may preclude subsequent allogeneic hematopoietic cell transplantation (allo-HCT). To determine the impact of pretransplant splenectomy on the incidence of allo-HCT, we conducted a comprehensive retrospective study of all patients with MF for whom an unrelated donor search had been initiated via the French bone marrow transplantation registry (RFGM) between 1 January 2008 and 1 January 2017. Additional data were collected from the patients' medical files and a database held by the French-Language Society for Bone Marrow Transplantation and Cell Therapy (SFGM-TC). We used a multistate model with four states ("RFGM registration"; "splenectomy"; "death before allo-HCT", and "allo-HCT") to evaluate the association between splenectomy and the incidence of allo-HCT. The study included 530 patients from 57 centers. With a median follow-up time of 6 years, we observed 81 splenectomies, 99 deaths before allo-HCT (90 without splenectomy and nine after), and 333 allo-HCTs (268 without splenectomy and 65 after). In a bivariable analysis, the hazard ratio [95% confidence interval (CI)] for the association of splenectomy with allo-HCT was 7.2 [5.1-10.3] in the first 4 months and 1.18 [0.69-2.03] thereafter. The hazard ratio [95% CI] for death associated with splenectomy was 1.58 [0.79-3.14]. These reassuring results suggest that splenectomy does not preclude allo-HCT in patients with MF.