Prognostic Factors and Risk Models in Myelodysplastic Syndromes

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

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

Prognostication in myelodysplastic syndromes (neoplasms): Molecular risk stratification finally coming of age

Accurate risk prognostication is central to the management of myelodysplastic syndromes, given the widely heterogeneous clinical outcomes of these bone marrow failure disorders. Over the past decade, the rapidly expanding compendium of molecular lesions in myelodysplastic syndrome (MDS) has offered unprecedented insight into MDS pathobiology. Recently, molecular prognostic models such as the Molecular International Prognostic Scoring System (IPSS-M) have leveraged the wellspring of genetic data to improve upon traditional risk models such as the Revised IPSS (IPSS-R), but also added substantial complexity. In this review, we highlight early MDS prognostic models, the significant advancements in MDS genomics since then, and the recent advent of molecular based prognostic models. We conclude by discussing important opportunities and challenges in the management of MDS as we arrive at the molecular frontier.

Myelodysplastic Syndromes: A New Decade

Myelodysplastic syndromes (MDS) are a group of heterogeneous clonal hematopoietic stem cell disorders. The 2020 Surveillance, Epidemiology, and End Results data demonstrates the incidence rate of MDS increases with age especially in those greater than 70 years of age. Risk stratification that impact prognosis, survival, and rate of acute myeloid leukemia (AML) transformation in MDS is largely dependent on revised International Prognostic Scoring System along with molecular genetic testing as a supplement. Low risk MDS typically have a more indolent disease course in which treatment is only initiated to ameliorate symptoms of cytopenias. In many, anemia is the most common cytopenia requiring treatment and erythroid stimulating agents, are considered first line. In contrast, high risk MDS tend to behave more aggressively for which treatment should be initiated rapidly with Hypomethylating Agents (HMA) being in the frontline. In those with high risk MDS and eligible, evaluation for allogeneic stem cell transplant should be considered as this is the only potential curative option for MDS. With the use of molecular genetic testing, a personalized approach to therapy in MDS has ensued. As the treatment landscape in MDS continues to flourish with novel targeted agents, we ambitiously seek to improve survival rates especially among the relapsed/refractory and transplant ineligible.

PAS positivity of erythroid precursor cells is associated with a poor prognosis in newly diagnosed myelodysplastic syndrome patients

Myelodysplastic syndrome (MDS) is a group of clonal stem cell disorders characterized by hematopoietic insufficiency. The accurate risk stratification of patients with MDS is essential for selection of appropriate therapies. We herein conducted a retrospective cohort study to examine the prognostic value of periodic acid-Schiff (PAS) reaction-positive erythroblasts in MDS patients. We examined the PAS positivity of the bone marrow erythroblasts of 144 patients newly diagnosed with MDS; 26 (18.1%) of them had PAS-positive erythroblasts, whereas 118 (81.9%) did not. The PAS-positive group showed significantly poorer karyotypes as defined in the revised International Prognostic Scoring System (IPSS-R) and higher scores in age-adjusted IPSS-R (IPSS-RA) than the PAS-negative group. Overall survival (OS) and leukemia-free survival (LFS) were also significantly shorter in the PAS-positive group than in the PAS-negative group. Similar results were obtained when only high- and very high risk groups were analyzed using IPSS-RA. This retrospective study suggested that the PAS positivity of erythroblasts is an additional prognostic factor combined with other risk scores for OS and LFS in MDS, and our results may contribute to improved clinical decision-making and rapid risk stratification.

Overcoming barriers to treating iron overload in patients with lower-risk myelodysplastic syndrome

Myelodysplastic syndromes (MDS) constitute a group of heterogeneous hematopoietic neoplasms characterized by ineffective erythropoiesis, anemia, and/or cytopenias. Supportive care for patients with MDS involves frequent red blood cell transfusions, which places patients with ongoing transfusional dependence (TD) at risk for iron overload (IO). Development of IO and tissue iron deposition can increase the risk of cardiac, hepatic, and endocrine toxicities, infection, and progression to acute myeloid leukemia. Iron chelation therapy (ICT) is an option for lower-risk MDS patients to reduce their degree of IO and possibly improve survival; use of these agents in thalassemia patients with TD and IO has been associated with reduced IO-associated complications and better survival. At present, there are several barriers to the regular use of ICT, such as a lack of randomized trial evidence and consistent guidance on diagnosis of IO and when to implement ICT, as well as barriers in adherence to/tolerability of ICT.

Current state of prognostication and risk stratification in myelodysplastic syndromes

PURPOSE OF REVIEW

Myelodysplastic syndromes (MDS) are characterized by significant biologic and clinical heterogeneity. Because of the wide outcome variability, accurate prognostication is vital to high-quality risk-adaptive care of MDS patients. In this review, we discuss the current state of prognostic schemes for MDS and overview efforts aimed at utilizing molecular aberrations for prognostication in clinical practice.

RECENT FINDINGS

Several prognostic instruments have been developed and validated with increasing accuracy and complexity. Oncologists should be aware of the inherent limitations of these prognostic tools as they counsel patients and make clinical decisions. As more therapies are becoming available for MDS, the focus of model development is shifting from prognostic to treatment-specific predictive instruments. In addition to providing additional prognostic data beyond traditional clinical and pathologic parameters, the improved understanding of the genetic landscape and pathophysiologic consequences in MDS may allow the construction of treatment-specific predictive instruments.

SUMMARY

How to best use the results of molecular mutation testing to inform clinical decision making in MDS is still a work in progress. Important steps in this direction include standardization in performance and interpretation of assays and better understanding of the independent prognostic importance of the recurrent mutations, especially the less frequent ones.

Factors associated with hematopoietic cell transplantation (HCT) among patients in a population-based study of myelodysplastic syndrome (MDS) in Minnesota

Myelodysplastic syndrome (MDS) is a clonal hematopoietic stem cell disorder characterized by dysplastic changes in the bone marrow, ineffective erythropoiesis, and an increased risk of developing acute myeloid leukemia. Treatment planning for patients with MDS is a complex process, and we sought to better characterize hematopoietic cell transplantation (HCT) outcomes and the factors that play into decision-making regarding referral of adults with MDS for definitive therapy with HCT. Patients enrolled in a population-based study of MDS between April 2010 and January 2013 who underwent HCT within the first year after enrollment were included in this analysis. Age- and risk-matched MDS patient controls also enrolled during that time period were used as a comparison. Survival was significantly better in the HCT group (48 vs. 21 %, log-rank p value 0.009). Non-HCT patients were more likely to have comorbidities, and HCT patients were more likely to have a college degree and an income >$80,000. All three of these variables were independently associated with HCT, but none impacted survival. Patients with MDS in our study who underwent HCT had better survival than a comparable group of patients who did not undergo HCT. With refined treatment techniques, more patients may be able to be considered for this therapy. More work needs to be done to determine why education and income appear to impact the decision to pursue HCT, but these factors may impact referral to an academic center where aggressive therapy like HCT is more likely to be considered.

Sequential azacitidine and lenalidomide in patients with high-risk myelodysplastic syndromes and acute myeloid leukaemia: a single-arm, phase 1/2 study

BACKGROUND

The standard of care for myelodysplastic syndromes is hypomethylating agents such as azacitidine. However, responses to azacitidine are generally temporary, and outcomes after hypomethylating agent failure are dismal. Therefore, the development of more effective treatments is crucial to improve outcomes in patients with myelodysplastic syndromes. We aimed to assess azacitidine and lenalidomide in patients with high-risk myelodysplastic syndromes and acute myeloid leukaemia.

METHODS

We did this single-arm phase 1/2 study at the University of Texas MD Anderson Cancer Center, TX, USA. Patients of any age were eligible for phase 1 and 2a if they had relapsed or refractory acute myeloid leukaemia or myelodysplastic syndrome with bone marrow blasts more than 10%. For phase 2b, eligible participants were previously untreated with myelodysplastic syndrome with an International Prognostic Scoring System (IPSS) score of intermediate-1 or higher with up to 30% blasts. All participants received 75 mg/m(2) azacitidine once a day for days 1-5 for each 28 day cycle. We gave patients oral lenalidomide for 5 or 10 days starting on day 6. We assessed seven lenalidomide doses in a 3 + 3 phase 1 design (n=28). The primary endpoint in phase 1 was the maximum tolerated dose, and the primary endpoint in phase 2 was overall survival. Outcome analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01038635.

FINDINGS

Between Dec 30, 2009, and June, 17, 2013, we enrolled 88 patients (28 in phase 1 and 60 in phase 2). One patient unexpectedly died in the phase 1 study at the highest dose level, six more patients were recruited with no further serious adverse events. We recorded no dose-limiting toxic effects, and the maximum tolerated dose of lenalidomide in combination with azacitidine in patients with acute myeloid leukaemia and myelodysplastic syndrome was initially established at 50 mg per day for 10 days. In the first 20 patients in phase 2, we noted a high rate of myelosuppression and myelosuppression-related toxic effects; therefore, we amended the lenalidomide dose to 25 mg per day for 5 days. We also adjusted the inclusion criteria to include patients with less than 30% blasts to focus mainly on patients with myelodysplastic syndromes. Median overall survival was 75 weeks (IQR 25-not reached) for the 40 patients in phase 2b. The most common grade 3-4 adverse events overall were neutropenic fever (n=27) and pneumonia (n=18).

INTERPRETATION

We have identified a safe and active sequential treatment combination of azacitidine and lenalidomide for patient with myelodysplastic syndrome and have preliminary evidence that this dose is also safe for patients with acute myeloid leukaemia.

FUNDING

MD Anderson Cancer Center and Celgene.

There's risk, and then there's risk: The latest clinical prognostic risk stratification models in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) include a diverse group of clonal hematopoietic disorders characterized by progressive cytopenias and propensity for leukemic progression. The biologic heterogeneity that underlies MDS translates clinically in wide variations of clinical outcomes. Several prognostic schemes were developed to predict the natural course of MDS, counsel patients, and allow evidence-based, risk-adaptive implementation of therapeutic strategies. The prognostic schemes divide patients into subgroups with similar prognosis, but the extent to which the prognostic prediction applies to any individual patient is more variable. None of these instruments was designed to predict the clinical benefit in relation to any specific MDS therapy. The prognostic impact of molecular mutations is being more recognized and attempts at incorporating it into the current prognostic schemes are ongoing.