Clinical impact and characteristics of erythroid dysplasia in adult aplastic anaemia: Results from a multicentre registry.

Morphological dysplasia in haematopoietic cells, defined by a 10% threshold in each lineage, is one of the diagnostic criteria for myelodysplastic neoplasms. Dysplasia limited to the erythroid lineage has also been reported in some cases of aplastic anaemia (AA); however, its significance remains unclear. We herein examined the impact of erythroid dysplasia on immunosuppressive therapy responses and survival in AA patients. The present study included 100 eligible AA patients without ring sideroblasts. Among them, 32 had dysplasia in the erythroid lineage (AA with minimal dysplasia [mini-D]). No significant sex or age differences were observed between AA groups with and without erythroid dysplasia. In severe/very severe AA and non-severe AA patients, a response to anti-thymocyte globulin + ciclosporin within 12 months was observed in 80.0% and 60.0% of AA with mini-D and 42.9% and 90.0% of those without dysplasia, with no significant difference (p = 0.29 and p = 0.24 respectively). Overall survival and leukaemia-free survival did not significantly differ between the groups. Collectively, the present results indicate that the presence of erythroid dysplasia did not significantly affect clinical characteristics or outcomes in AA patients, suggesting that its presence in AA is acceptable. Therefore, erythroid dysplasia should not exclude an AA diagnosis.

Myelodysplastic syndromes with ring sideroblasts.

Myelodysplastic syndromes (MDS) are acquired bone marrow malignant disorders characterized by ineffective hematopoiesis, resulting from a complex interaction between genetic and epigenetic mutations, alterations of the marrow microenvironment, and the immune system. In 2001, the World Health Organization (WHO) proposed a classification that integrates morphologic and genetic information, considering the MDS with ring sideroblasts (MDS-RS) as a distinct entity. Considering the strong association between MDS-RS and SF3B1 mutation and its importance in the development of MDS, the last WHO classification replaced the prior entity of MDS-RS with MDS with SF3B1 mutation. Several studies were performed to explore this genotype-phenotype correlation. Mutant SF3B1 protein deregulates the expression of genes implicated in developing hematopoietic stem and progenitor cells. Of paramount importance are PPOX and ABCB7 involved in iron metabolism. Another essential role in hemopoiesis is played by the transforming growth factor-beta (TGF-ß) receptor. This gene exerts its effects on SMAD pathways, regulating hematopoiesis through effects on balancing proliferation and apoptosis cell inactivity, differentiation, and migration. Luspatercept (ACE-536) is a soluble fusion protein that inhibits molecules in the TGF-ß superfamily. Since its structure resembles the TGF-ß family receptor, it catches TGF-ß superfamily ligands before binding to the receptor, resulting in reduced activation of SMAD signaling, thus enabling erythroid maturation. Luspatercept was investigated in the phase III trial MEDALIST, showing promising efficacy in treating anemia compared to placebo. Nowadays, further studies are needed to explore the real potential of luspatercept, investigating the biological features likely associated with treatment response, the potential use in combination treatments, and its role in the treatment of naïve MDS.

Luspatercept in combination with recombinant erythropoietin in patients with myelodysplastic syndrome with ring sideroblasts: Stimulating early and late-stage erythropoiesis.

Patients with myelodysplastic syndromes and ring sideroblasts (MDS RS) are clinically characterized by severe anemia and transfusion need. Erythropoiesis-stimulating agents (ESAs), which stimulate hemoglobin production and early maturation of erythroid precursors, are effective only in a portion of patients and for limited time. Luspatercept, an inhibitor of the TGF-beta pathway, is beneficial in unblocking late-stage erythropoiesis and has been approved for MDS RS patients failing or not-candidate to ESAs. ESAs and/or luspatercept failure represents an unmet clinical need and most patients become life-long transfusion dependent. Here, we describe the clinical combination of luspatercept with ESAs (subcutaneous epoetin alpha 40-80 000 IU/week) in seven MDS RS patients. Two patients had ESAs as pre-existing therapy, while five were re-challenged with ESAs as add-on treatment due to luspatercept failure. Three patients achieved hematologic improvement, and one became transfusion independent. No adverse events were noted. This is the first clinical evidence that stimulating both early and late-stage erythropoiesis may offer a further option for this challenging patient population.

Red blood cell transfusion burden in myelodysplastic syndromes (MDS) with ring Sideroblasts (RS): A retrospective multicenter study by the Groupe Francophone des Myélodysplasies (GFM).

BACKGROUND: MDS-RS patients are characterized by chronic anemia and a low risk of Acute Myeloid Leukemia (AML) progression and they generally become Red Blood Cell (RBC) transfusion dependent (TD). STUDY DESIGN AND METHODS: We performed a retrospective "real-life" observational study of 6 months in 100 MDS-RS TD patients, recruited in 12 French centers, to describe transfusion characteristics, and evaluate the frequency and causes of hospitalizations, health costs, and morbidity, associated with transfusion dependency, in a French population of RBC transfusion-dependent MDS-RS patients. RESULTS: 79% of the patients had high transfusion burden (HTB) and 21% low transfusion burden (LTB). HTB patients had a longer disease duration (6 vs. 3.7 years, p = 0.0078), more frequent iron chelation (82% vs. 50%, p = 0.0052) and higher serum ferritin (p = 0.03). During the 6-month study period, 22% of the patients required inpatient hospitalization, 36% of them for symptomatic anemia requiring emergency RBC transfusion. The 6-month median transfusion costs, including the cost of the day care facility, transportation to and from the hospital, iron chelation, and lab tests, was 16,188€/patient. DISCUSSION: MDS-RS represents the archetypal type of chronically transfused lower-risk MDS. Most of those patients have a high transfusion burden and thus frequently need visits to the hospital's day care facility, and frequent hospitalizations, with an overall high median treatment cost. Those costs should be compared with costs of new treatments potentially able to avoid RBC transfusion dependence and to reduce the complications of chronic anemia in MDS-RS patients.

Only SF3B1 mutation involving K700E independently predicts overall survival in myelodysplastic syndromes.

BACKGROUND: SF3B1 mutations (SF3B1mut ) in myelodysplastic syndromes (MDS) frequently involve codon K700E and have a favorable prognosis. The prognostic effect of non-K700E SF3B1mut is uncertain. METHODS: The authors analyzed the clinicopathological features and outcomes of a single-institution series of 94 treatment-naive SF3B1mut MDS patients (18%) and 415 treatment-naive SF3B1wt MDS patients and explored the differences between K700E and non-K700E SF3B1mut MDS. RESULTS: Fifty-five patients (59%) carried K700E. Recurrent non-K700E mutations (39 [41%]) included R625, H662, and K666. Compared with SF3B1mut K700E patients, non-K700E patients had a lower median absolute neutrophil count (1.8 vs 2.4; P = .005) and were frequently "high" according to the Revised International Prognostic Scoring System (19% vs 4%; P = .031). Non-K700E MDS was associated frequently with RUNX1 (26% vs 7%; P = .012) and exclusively with BCOR, IDH2, and SRSF2 mutations. A splicing analysis showed the differential distribution of alternatively spliced events and gene expression profiles between K700 and non-K700E MDS patients. The majority (at least 80%) of SF3B1mut K700E, SF3B1mut non-K700E, and SF3B1wt patients were treated with hypomethylating agents. Over a median follow-up of 16 months, SF3B1mut had superior overall survival (OS) in comparison with SF3B1wt in all MDS patients (not reached vs 25.2 months; P = .0003), in patients with low-grade MDS, and in patients with myelodysplastic syndromes with ring sideroblasts (MDS-RS). Compared with SF3B1wt , SF3B1mut K700E had superior outcomes in all MDS (median OS, 25 months vs not reached; P = .0001), in low-grade MDS (median OS, 41.3 months vs not reached; P = .0015), and in MDS-RS (median OS, 22.3 months vs not reached; P = .0001), but no significant difference was seen between non-K700E and SF3B1wt MDS. By multivariable analysis, the absence of SF3B1mut K700E mutations was independently associated with the prognosis. CONCLUSIONS: This study highlights the importance of the SF3B1 mutation subtype in MDS risk assessment. LAY SUMMARY: Myelodysplastic syndromes (MDS) with SF3B1 mutations are regarded as having a favorable prognosis by both the World Health Organization and the International Working Group for the Prognosis of Myelodysplastic Syndromes. However, this article shows that only MDS patients with SF3B1 K700E mutations have a favorable prognosis (and not MDS patients with SF3B1 mutations involving other codons). This has important implications for refining future MDS subclassification and risk assessment criteria.

Evaluation of multiparametric flow cytometry in diagnosis & prognosis of myelodysplastic syndrome in India.

Background & objectives: Diagnosis of myelodysplastic syndromes (MDS) is subjective in low-grade cases with <5 per cent blasts or <15 per cent ring sideroblasts. Flow cytometry (FCM) has been used to diagnose MDS; but, it still has only an adjunctive role. This study was conducted to evaluate the role of FCM to diagnose MDS and correlate the number of aberrancies with revised international prognostic scoring system (R-IPSS). Methods: This study included 44 consecutive clinically suspected cases of MDS with refractory cytopenia(s) and 10 controls. Patients were divided into two groups: (i) proven MDS cases (n=26), and (ii) suspected MDS (n=18). Ogata quantitative approach, pattern analysis and aberrant antigen expression were studied. Results: Ogata score ≥2 correctly diagnosed 80.7 per cent (21/26) while aberrant antigen and pattern analysis with flow score of ≥3 could diagnose 92.3 per cent (24/26) patients with proven MDS. Combination of both with flow score ≥3 could diagnose 100 per cent patients. Eight patients in suspected MDS group with persistent cytopenia on follow up were labelled as probable MDS. Ogata score ≥2 was present in 5 of 8 and pattern analysis score ≥3 was present in six probable MDS patients. Combination of both with flow score ≥3 was present in seven of eight patients. Spearman's correlation between Ogata score and R-IPSS, pattern analysis and R-IPSS and combination of both scores and R-IPSS showed significant positive correlation in proven MDS as well as when proven and probable MDS patients were combined. Interpretation & conclusions: Our results showed that combined Ogata approach and pattern analysis, demonstration of ≥3 aberrancies in >1 cell compartment could diagnose most MDS patients. Patients with high flow scores had high R-IPSS scores. Patient with flow score ≥3 and borderline cytomorphology should be observed closely for the development of MDS.

[Ring sideroblasts and iron metabolism].

Ring sideroblasts show abnormal mitochondrial iron accumulation, and their emergence in the bone marrow is a characteristic of sideroblastic anemias (SAs). SAs are a group of heterogeneous congenital and acquired disorders. Congenital SA is a rare disease caused by gene mutations involved in heme biosynthesis, iron-sulfur cluster biosynthesis, and mitochondrial protein synthesis. SAs can also occur after exposure to certain drugs or alcohol and due to copper deficiency (secondary SA). Furthermore, SAs are associated with myelodysplastic syndrome (idiopathic SA), strongly correlating with specific somatic mutations in splicing factor 3b subunit 1 (SF3B1), which is involved in the RNA splicing machinery. Recent reports have indicated that common defects in iron/heme metabolism underlie in the mechanisms of ring sideroblast formation in congenital and acquired SAs. Current understanding of SA pathophysiology, including the mechanisms of ring sideroblast formation, is discussed in this review.

Systemic mastocytosis associated with myelodysplastic/myeloproliferative neoplasms with ring sideroblasts and thrombocytosis: Report of three cases.

The association of systemic mastocytosis with another hematologic neoplasia of myeloid or lymphoid origin is recognized as an advanced subvariant of mastocytosis. Here, we report the association of indolent or smoldering systemic mastocytosis with three cases of myelodysplastic/myeloproliferative neoplasms with ring sideroblasts and thrombocytosis, a recently recognized disease characterized by SF3B1 mutations. The hierarchical pattern of KIT, SF3B1, JAK2, and additional mutations was studied in whole and fractionated subpopulations of peripheral blood cells and whole bone marrow. In two cases, we could demonstrate a multilineage D816V KIT mutation, involving all myeloid lineages in one patient and also the lymphoid series in the other. Two patients displaying both SF3B1 and V617F JAK2 mutations had a very poor prognosis. Another patient bearing SF3B1, but not V617F JAK2 mutation, had a favorable response to erythropoietin treatment and long survival.

Sideroblastic anemia associated with multisystem mitochondrial disorders.

BACKGROUND: Sideroblastic anemia represents a heterogeneous group of inherited or acquired diseases with disrupted erythroblast iron utilization, ineffective erythropoiesis, and variable systemic iron overload. In a cohort of 421 patients with multisystem mitochondrial diseases, refractory anemia was found in 8 children. RESULTS: Five children had sideroblastic anemia with increased numbers of ring sideroblasts >15%. Two of the children had a fatal course of MLASA1 syndrome (mitochondrial myopathy, lactic acidosis, and sideroblastic anemia [SA]) due to a homozygous, 6-kb deletion in the PUS1 gene, part of the six-member family of pseudouridine synthases (pseudouridylases). Large homozygous deletions represent a novel cause of presumed PUS1-loss-of-function phenotype. The other three children with SA had Pearson syndrome (PS) due to mtDNA deletions of 4 to 8 kb; two of these children showed early onset of PS and died due to repeated sepsis; the other child had later onset of PS and survived as the hematological parameters normalized and the disease transitioned to Kearns-Sayre syndrome. In addition, anemia without ring sideroblasts was found in three other patients with mitochondrial disorders, including two children with later onset of PS and one child with failure to thrive, microcephaly, developmental delay, hypertrophic cardiomyopathy, and renal tubular acidosis due to the heterozygous mutations c.610A>G (p.Asn204Asp) and c.674C>T (p.Pro225Leu) in the COX10 gene encoding the cytochrome c oxidase assembly factor. CONCLUSIONS: Sideroblastic anemia was found in fewer than 1.2% of patients with multisystem mitochondrial disease, and it was usually associated with an unfavorable prognosis.

Myelodysplastic Syndrome Updated.

This review highlights the main changes in the revised 2016 WHO Classification of Myeloid Neoplasms (published in 2017) that impact the diagnosis and management of patients with myelodysplastic syndrome (MDS). The revision was based on data accumulated since the 2008 WHO classification of MDS, much of which relates to new molecular genetic information about these neoplasms. The new information has led to some reorganization of the MDS disease categories, including a broadening of the subset of cases classified as MDS with ring sideroblasts, many of which have mutations in the spliceosome gene SF3B1. Other revisions have refined the definitions of some disease categories to improve disease risk stratification. The revised categories in the new classification ensure that MDS patients receive risk-adapted therapies based on the most recently available data.

[Sideroblastic anemia].

Sideroblastic anemia (SA) signifies a group of heterogeneous congenital and acquired disorders characterized by anemia and the presence of ring sideroblasts in the bone marrow. Congenital SA is a rare disease caused by mutations of genes involved in heme biosynthesis, iron-sulfur cluster biosynthesis, and mitochondrial protein synthesis. In addition, SA can occur after exposure to certain drugs or alcohol and because of copper deficiency (secondary SA). Of note, SA also correlates with myelodysplastic syndrome (idiopathic SA). Recent progress in the genome analysis technology has enabled the identification of novel causative genes for SA, elucidating the molecular pathophysiology of these disorders. Accordingly, the significance of genetic diagnosis for SA has been increasing. This review discusses the current understanding of genetic mutations involved in the pathophysiology of SA.

[Splicing factor mutations in myelodysplastic syndromes].

Splicing factor mutations represent a novel class of driver mutations in myelodysplastic syndromes, where four genes, including SF3B1, SRSF2, U2AF1, and ZRSR2, are most frequently affected. SF3B1 and SRSF2 mutations show prominent specificity to the syndrome subtypes characterized by increased ring sideroblasts and chronic myelomonocytic leukemia, respectively. These mutations are suspected to be involved in the pathogenesis of the above mentioned syndromes most likely via abnormal RNA splicing. However, the precise mechanism and target genes have not been fully understood. Splicing alterations induced by these mutations are extensively studied using RNA sequencing. SF3B1 mutations caused misrecognition of 3' splice sites. Target genes included those involved in mitochondrial iron metabolism or heme biosynthesis, such as ABCB7 and PPOX, suggesting a role in the abnormal erythropoiesis associated with increased ring sideroblasts. By contrast, SRSF2 and U2AF1 mutations were mainly associated with alternative exon usage in hundreds of genes. The targets included genes of which mutations are definitive or putative drivers in myeloid malignancies. Protein structure modeling and experiments with cell lines and mouse models supported these findings. ZRSR2 mutations were associated with the retention of U12-type introns, and this is consistent with the known role of ZRSR2 as an essential component of the U12-type spliceosome. Further studies are warranted to determine the biological effects of splicing alterations.

Biology of sideroblastic anemia.

Sideroblastic anemia is characterized by anemia with ring sideroblasts produced by the bone marrow. Sideroblasts are formed by disutilization and deposit of iron in the mitochondoria. There are two forms of sideroblastic anemia: congenital and acquired. Congenital sideroblastic anemia is caused by mutations in genes involved in heme biosynthesis, iron-sulfur (Fe-S) cluster biogenesis, or mitochondrial metabolism. Although there is a variation in the mutated genes among races, the most common congenital sideroblastic anemia is X-linked sideroblastic anemia caused by mutations in the erythroid-specific δ-aminolevulinate synthase gene, which is the first enzyme of heme biosynthesis in erythroid cells. The most commonly acquired sideroblastic anemia is myelodysplastic syndrome with ring sideroblasts (MDS-RS). It has been shown that the splicing factor 3b subunit 1 (SF3B1) gene, which is a core component of the RNA splicing complex, is highly mutated in MDS-RS, although the underlying mechanism of the onset of the disease by the mutation of the SF3B1 gene remains unclear. Molecular analysis will contribute to the development of effective treatment for congenital and acquired sideroblastic anemia, which are intractable diseases.

Recent advances in the understanding of myelodysplastic syndromes with ring sideroblasts.

Myeloid neoplasms with ring sideroblasts are currently categorized within the myelodysplastic syndromes (MDS) or myelodysplastic/myeloproliferative neoplasms (MDS/MPN) in the World Health Organization classification. Recent findings have identified that the presence of ring sideroblasts in these disorders has a unique molecular basis, i.e., the somatic mutation of SF3B1, a gene encoding a splicing factor. Mutations of SF3B1 occur in up to 90% of patients with refractory anaemia with unilineage dysplasia (RARS) and 70% of those with refractory cytopenia with multilineage dysplasia and ring sideroblasts or RARS associated with marked thrombocytosis. Experimental evidence has shown that mutant SF3B1 results in the abnormal splicing of several genes, primarily due to misrecognition of 3' splice sites. The resulting aberrant mRNAs undergo nonsense-mediated mRNA decay (NMD), resulting in haploinsufficiency of canonical transcripts and protein expression. In addition, it is also possible that NMD-insensitive aberrant transcripts are translated into proteins with altered function. Patients with MDS carrying the SF3B1 mutation show a homogeneous disease phenotype characterized by isolated erythroid dysplasia and mild dysplasia in granulocytic or megakaryocytic lineages, supporting the notion that the SF3B1 mutation identifies a distinct entity within MDS. The available evidence suggests that these findings may have relevant impact on the diagnosis, classification and management of patients with these neoplasms.

Aberrant splicing of genes involved in haemoglobin synthesis and impaired terminal erythroid maturation in SF3B1 mutated refractory anaemia with ring sideroblasts.

Refractory anaemia with ring sideroblasts (RARS) is distinguished by hyperplastic inefficient erythropoiesis, aberrant mitochondrial ferritin accumulation and anaemia. Heterozygous mutations in the spliceosome gene SF3B1 are found in a majority of RARS cases. To explore the link between SF3B1 mutations and anaemia, we studied mutated RARS CD34(+) marrow cells with regard to transcriptome sequencing, splice patterns and mutational allele burden during erythroid differentiation. Transcriptome profiling during early erythroid differentiation revealed a marked up-regulation of genes involved in haemoglobin synthesis and in the oxidative phosphorylation process, and down-regulation of mitochondrial ABC transporters compared to normal bone marrow. Moreover, mis-splicing of genes involved in transcription regulation, particularly haemoglobin synthesis, was confirmed, indicating a compromised haemoglobinization during RARS erythropoiesis. In order to define the phase during which erythroid maturation of SF3B1 mutated cells is most affected, we assessed allele burden during erythroid differentiation in vitro and in vivo and found that SF3B1 mutated erythroblasts showed stable expansion until late erythroblast stage but that terminal maturation to reticulocytes was significantly reduced. In conclusion, SF3B1 mutated RARS progenitors display impaired splicing with potential downstream consequences for genes of key importance for haemoglobin synthesis and terminal erythroid differentiation.

An Autopsy Case of Severe COVID-19 Pneumonia Complicated by Intrapulmonary Thrombosis in Myelodysplastic/Myeloproliferative Neoplasm With Ring Sideroblasts and Thrombocytosis.

Patients with coronavirus disease 2019 (COVID-19) pneumonia are prone to intrapulmonary thrombosis owing to excessive inflammation and platelet activation. Myelodysplastic/myeloproliferative neoplasm (MDS/MPN) with ring sideroblasts and thrombocytosis (RS-T) is a rare disease in MDS/MPN overlap entities. Patients with MDS/MPN RS-T are known to be at a high risk of thrombosis, and platelet count control with drug therapy does not necessarily reduce this risk. Here, we report the autopsy case of an older male patient with MDS/MPN RS-T and severe COVID-19 pneumonia complicated by intrapulmonary thrombosis. His platelet count had been controlled in the normal range after treatment with hydroxyurea and 5-aza-2'-deoxycytidine. On admission day, he rapidly developed respiratory distress and tested positive on a polymerase chain reaction test for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). After admission, he received supplemental oxygen and was administered remdesivir and dexamethasone; however, his respiratory and circulatory status did not improve. The patient died on day 4 of illness. Autopsy findings revealed massive thrombi within blood vessels and diffuse alveolar damage in both lungs, which were determined to be the cause of death. In patients with MDS/MPN RS-T combined with COVID-19 pneumonia, clinicians may need to pay close attention to the risk of pulmonary thrombosis.

[Clinical characteristics and prognosis of patients with myelodysplastic syndrome with a bone marrow nucleated erythroid cell proportion of greater than or equal to 50].

Objective: To analyze the clinical characteristics and prognosis of patients with myelodysplastic syndrome (MDS) with a bone marrow nucleated erythroid cell proportion of greater than or equal to 50% (MDS-E) . Methods: The clinical characteristics and prognostic factors of patients with MDS-E were retrospectively analyzed by collecting the case data of 1 436 newly treated patients with MDS diagnosed in the Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences from May 2014 to June 2023. Results: A total of 1 436 newly diagnosed patients with complete data were included in the study, of which 337 (23.5%) patients with MDS-E had a younger age of onset and lower neutrophil and platelet counts compared with those in patients with an erythroid cell proportion of less than 50% (MDS-NE) (all P<0.05). The proportion of MDS cases with ring sideroblasts (MDS-RS) was higher in the MDS-E group than in the MDS-NE group, and multi-hit TP53 mutations were more enriched in the MDS-E group than in the MDS-NE group (all P<0.05). Among patients with MDS-RS, the frequency of complex karyotypes and the TP53 mutation rate were significantly lower in the MDS-E group than in the MDS-NE group (0 vs 11.9%, P=0.048 and 2.4% vs 15.1%, P=0.053, respectively). Among patients with TP53 mutations, the frequencies of complex karyotypes and multi-hit TP53 mutations were significantly higher in the MDS-E group than in the MDS-NE group (87.5% vs 64.6%, P=0.003 and 84.0% vs 54.2%, P<0.001, respectively). Survival analysis of patients with MDS-RS found that the overall survival (OS) in the MDS-E group was better than that in the MDS-NE group [not reached vs 63 (95% CI 53.3-72.7) months, P=0.029]. Among patients with TP53 mutations and excess blasts, the OS in the MDS-E group was worse than that in the MDS-NE group [6 (95% CI 2.2-9.8) months vs 12 (95% CI 8.9-15.1) months, P=0.022]. Multivariate analysis showed that age of ≥65 years (HR=2.47, 95% CI 1.43-4.26, P=0.001), mean corpuscular volume (MCV) of ≤100 fl (HR=2.62, 95% CI 1.54-4.47, P<0.001), and TP53 mutation (HR=2.31, 95% CI 1.29-4.12, P=0.005) were poor prognostic factors independent of the Revised International Prognostic Scoring System (IPSS-R) prognosis stratification in patients with MDS-E. Conclusion: Among patients with MDS-RS, MDS-E was strongly associated with a lower proportion of complex karyotypes and TP53 mutations, and the OS in the MDS-E group was longer than that in the MDS-NE group. Among patients with TP53 mutations, MDS-E was strongly associated with complex karyotypes and multi-hit TP53 mutations, and among TP53-mutated patients with excess blasts, the OS in the MDS-E group was shorter than that in the MDS-NE group. Age of ≥65 years, MCV of ≤100 fl, and TP53 mutation were independent adverse prognostic factors affecting OS in patients with MDS-E.

Myelodysplastic Neoplasms (MDS) with Ring Sideroblasts or SF3B1 Mutations: The Improved Clinical Utility of World Health Organization and International Consensus Classification 2022 Definitions, a Single-Centre Retrospective Chart Review.

Myelodysplastic neoplasms (MDS) with ring sideroblasts (RS) are diagnosed via bone marrow aspiration in the presence of either (i) ≥15% RS or (ii) 5-14% RS and an SF3B1 mutation. In the MEDALIST trial and in an interim analysis of the COMMANDS trial, lower-risk MDS-RS patients had decreased transfusion dependency with luspatercept treatment. A total of 6817 patients with suspected hematologic malignancies underwent molecular testing using a next-generation-sequencing-based genetic assay and 395 MDS patients, seen at our centre from 1 January 2018 to 31 May 2023, were reviewed. Of these, we identified 39 evaluable patients as having lower-risk MDS with SF3B1 mutations: there were 20 (51.3%) males and 19 (48.7%) females, with a median age of 77 years (range of 57 to 92). Nineteen (48.7%) patients had an isolated SF3B1 mutation with a mean variant allele frequency of 35.2% +/- 8.1%, ranging from 7.4% to 46.0%. There were 29 (74.4%) patients with ≥15% RS, 6 (15.4%) with 5 to 14% RS, one (2.6%) with 1% RS, and 3 (7.7%) with no RS. Our study suggests that a quarter of patients would be missed based on the morphologic criterion of only using RS greater than 15% and supports the revised 2022 definitions of the World Health Organization (WHO) and International Consensus Classification (ICC), which shift toward molecularly defined subtypes of MDS and appropriate testing.

Morphologic Characteristics of Myelodysplastic Syndromes.

Morphologic characterization remains a cornerstone in the diagnosis and classification of myelodysplastic syndromes (MDS) in the updated International Consensus Classification (ICC) and 5th edition World Health Organization Classification of Myeloid Neoplasms (Arber, Orazi, & Hasserjian, 2022; Khoury & Solary, 2022). The presence of dysplasia is one of the key diagnostic criteria required for establishing a diagnosis of MDS, and the percentage of myeloblasts in the blood and bone marrow impacts both disease classification and prognostication. Morphologic features also aid in distinguishing MDS from a myriad of other myeloid neoplasms and non-neoplastic mimics. Additional key morphologic features that should be recorded in any MDS case are the bone marrow cellularity and the degree of reticulin fibrosis. In this review, the morphologic assessment of the bone marrow biopsy, bone marrow aspirate, and peripheral blood smear as it pertains to the diagnosis and up-to-date classification of MDS will be described. The implications of the findings on classification and prognosis will also be discussed.

A case of MDS/MPN overlap syndrome with ring sideroblasts and thrombocytosis: Tackling the quandary of thrombosis versus hemorrhage.

Key Clinical Message: No formal treatment guidelines for MDS/MPN-RS-T exist. With salient features such as anemia and thrombocytosis, management is individualized and aims to address anemia, thrombosis, and in some cases acquired von Willebrand's disease. Abstract: Myelodysplastic/myeloproliferative overlap syndrome with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T) is a rare myeloid neoplasm showing myelodysplastic and myeloproliferative features. With extremely raised platelets, possibility of acquired von Willebrand and risk of hemorrhage is increased. With this quandary in mind, a descriptive case and a brief discussion of available treatments ensues.