Real-world status of treatment for lymphoid neoplasms developed during the course of myeloproliferative neoplasms in Japan.

OBJECTIVES: Patients with myeloproliferative neoplasms (MPNs) are at higher risk of developing secondary malignancies. In this study, we focused on patients with MPNs that complicated lymphoid neoplasms. To analyze the real-world status of lymphoid neoplasm treatment in patients with pre-existing MPNs in Japan, we conducted a multicenter retrospective study. METHODS: Questionnaires were sent to collect the data on patients who were first diagnosed with either polycythemia vera, essential thrombocythemia or myelofibrosis and who later were complicated with lymphoid neoplasms defined as malignant lymphoma, multiple myeloma, or chronic lymphocytic leukemia/small cell lymphoma. RESULTS: Twenty-four patients with MPNs complicated by lymphoid neoplasms were enrolled (polycythemia vera, n = 8; essential thrombocythemia, n = 14; and primary myelofibrosis, n = 2). Among these, diffuse large B-cell lymphoma (DLBCL) was the most frequently observed (n = 13, 54.1%). Twelve (92.3%) of the patients with DLBCL received conventional chemotherapy. Among these 12 patients, regarding cytoreductive therapy for MPNs, 8 patients stopped treatment, one continued treatment, and two received a reduced dose. Consequently, most patients were able to receive conventional chemotherapy for DLBCL with a slightly higher dose of granulocyte colony-stimulating factor support than usual without worse outcomes. All 3 patients with multiple myeloma received a standard dose of chemotherapy. CONCLUSION: Our data indicate that if aggressive lymphoid neoplasms develop during the course of treatment in patients with MPNs, it is acceptable to prioritize chemotherapy for lymphoma.

[SFCE harmonization workshops: Neonatal acute myeloid leukemia]. / Orientation et prise en charge de la leucémie aiguë myéloïde néonatale : recommandations du comité leucémies de la SFCE.

Neonatal acute myeloid leukemias (AML) occurred within the first 28 days of life and constitute only a small proportion of all AL. They are distinguished from leukemias of older children by their clinical presentation, which frequently includes cutaneous localizations ("blueberry muffin rash syndrome") and a leukocytosis above 50 ×109/L. This proliferation may be transient, causing a transient leukemoid reaction in a background of constitutional trisomy 21 ("Transient Abnormal Myelopoieseis" or TAM) or Infantile Myeloproliferative Disease in the absence of constitutional trisomy 21 ("Infantile Myeloproliferative Disease" or IMD). In cases of true neonatal AML, the prognosis of patients is poor. Overall survival is around 35 % in the largest historical series. This poor prognosis is mainly due to the period of onset of this pathology making the use of chemotherapy more limited and involving many considerations, both ethical and therapeutic. The objective of this work is to review this rare pathology by addressing the clinical, biological, therapeutic and ethical particularities of patients with true neonatal AML or transient leukemoid reactions occurring in a constitutional trisomy 21 (true TAM) or somatic background (IMD).

Germline predisposition to myeloid neoplasms: Characteristics and management of high versus variable penetrance disorders.

Myeloid neoplasms with germline predisposition have been recognized increasingly over the past decade with numerous newly described disorders. Penetrance, age of onset, phenotypic heterogeneity, and somatic driver events differ widely among these conditions and sometimes even within family members with the same variant, making risk assessment and counseling of these individuals inherently difficult. In this review, we will shed light on high malignant penetrance (e.g., CEBPA, GATA2, SAMD9/SAMD9L, and TP53) versus variable malignant penetrance syndromes (e.g., ANKRD26, DDX41, ETV6, RUNX1, and various bone marrow failure syndromes) and their clinical features, such as variant type and location, course of disease, and prognostic markers. We further discuss the recommended management of these syndromes based on penetrance with an emphasis on somatic aberrations consistent with disease progression/transformation and suggested timing of allogeneic hematopoietic stem cell transplant. This review will thereby provide important data that can help to individualize and improve the management for these patients.

Treatment of patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN): focus on the use of tagraxofusp and clinical considerations.

BPDCN is an aggressive myeloid malignancy with a poor prognosis. It derives from the precursors of plasmacytoid dendritic cells and is characterized by CD123 overexpression, which is seen in all patients with BPDCN. The CD123-directed therapy tagraxofusp is the only approved treatment for BPDCN; it was approved in the US as monotherapy for the treatment of patients aged ≥2 years with treatment-naive or relapsed/refractory BPDCN. Herein, we review the available data supporting the utility of tagraxofusp in treating patients with BPDCN. In addition, we present best practices and real-world insights from clinicians in academic and community settings in the US on how they use tagraxofusp to treat BPDCN. Several case studies illustrate the efficacy of tagraxofusp and discuss its safety profile, as well as the prevention, mitigation, and management of anticipated adverse events.

Analytical Validation of a 37-Gene Next-Generation Sequencing Panel for Myeloid Malignancies and Review of Initial Findings Incorporating Updated 2022 Diagnostic and Prognostic Guidelines.

Myeloid neoplasms are clonal disorders that arise via acquisition of genetic mutations leading to excessive proliferation and defective differentiation. Mutational profiling is vital as it has implications for diagnosis, prognosis, and therapeutic decision-making. Next-generation sequencing (NGS) has become a mainstay in the evaluation of myeloid malignancies, as it enables efficient characterization of multiple genetic changes. Herein, the analytical validation of the 37-gene Archer VariantPlex Core Myeloid panel is reported, using 58 DNA specimens with 87 single-nucleotide variants and 23 insertions/deletions. The panel achieved good depth of coverage, 100% analytical sensitivity and specificity for single-nucleotide variants and insertions/deletions ≤21 bp, and 100% reproducibility, with a reportable limit of detection determined as 5%. The Archer NGS panel can accurately and reproducibly detect variants of clinical significance in myeloid neoplasms. A retrospective analysis of 535 clinical specimens tested with the Archer NGS panel showed a frequency and pattern of mutations across myeloid malignancies that were similar to other published studies. A review of the diagnostic classification of patients with acute myeloid leukemia and myelodysplastic syndrome using the World Health Organization 2017/2022 and International Consensus Classification 2022 guidelines, in addition to European LeukemiaNet 2017/2022 risk stratification of patients with acute myeloid leukemia, was also performed to assess the utility of the molecular information provided by the Archer NGS panel.

Liquid biopsy-based circulating tumour (ct)DNA analysis of a spectrum of myeloid and lymphoid malignancies yields clinically actionable results.

AIMS: Liquid biopsy (LBx)-based next-generation sequencing (NGS) of circulating tumour DNA (ctDNA) can facilitate molecular profiling of haematopoietic neoplasms (HNs), particularly when tissue-based NGS is infeasible. METHODS AND RESULTS: We studied HN LBx samples tested with FoundationOne Liquid CDx, FoundationOne Liquid, or FoundationACT between July 2016 and March 2022. We identified 271 samples: 89 non-Hodgkin lymphoma (NHL), 43 plasma-cell neoplasm (PCN), 41 histiocytoses, 27 myelodysplastic syndrome (MDS), 25 diffuse large B-cell lymphoma (DLBCL), 22 myeloproliferative neoplasm (MPN), 14 Hodgkin lymphoma (HL), and 10 acute myeloid leukaemia (AML). Among 73.4% with detectable pathogenic alterations, median maximum somatic allele frequency (MSAF) was 16.6%, with AML (36.2%), MDS (19.7%), and MPN (44.5%) having higher MSAFs than DLBCL (3.9%), NHL (8.4%), HL (1.5%), PCN (2.8%), and histiocytoses (1.8%) (P = 0.001). LBx detected characteristic alterations across HNs, including in TP53, KRAS, MYD88, and BTK in NHLs; TP53, KRAS, NRAS, and BRAF in PCNs; IGH in DLBCL; TP53, ATM, and PDCD1LG2 in HL; BRAF and MAP2K1 in histiocytoses; TP53, SF3B1, DNMT3A, TET2, and ASXL1 in MDS; JAK2 in MPNs; and FLT3, IDH2, and NPM1 in AML. Among 24 samples, the positive percent agreement by LBx was 75.7% for variants present in paired buffy coat, marrow, or tissues. Also, 75.0% of pairs exhibited alterations only present on LBx. These were predominantly subclonal (clonal fraction of 3.8%), reflecting the analytical sensitivity of LBx. CONCLUSION: These data demonstrate that LBx can detect relevant genomic alterations across HNs, including at low clonal fractions, suggesting a potential clinical utility for identifying residual or emerging therapy-resistant clones that may be undetectable in site-specific tissue biopsies.

Exploring the Molecular Aspects of Myeloproliferative Neoplasms Associated with Unusual Site Vein Thrombosis: Review of the Literature and Latest Insights.

Myeloproliferative neoplasms (MPNs) are the leading causes of unusual site thrombosis, affecting nearly 40% of individuals with conditions like Budd-Chiari syndrome or portal vein thrombosis. Diagnosing MPNs in these cases is challenging because common indicators, such as spleen enlargement and elevated blood cell counts, can be obscured by portal hypertension or bleeding issues. Recent advancements in diagnostic tools have enhanced the accuracy of MPN diagnosis and classification. While bone marrow biopsies remain significant diagnostic criteria, molecular markers now play a pivotal role in both diagnosis and prognosis assessment. Hence, it is essential to initiate the diagnostic process for splanchnic vein thrombosis with a JAK2 V617F mutation screening, but a comprehensive approach is necessary. A multidisciplinary strategy is vital to accurately determine the specific subtype of MPNs, recommend additional tests, and propose the most effective treatment plan. Establishing specialized care pathways for patients with splanchnic vein thrombosis and underlying MPNs is crucial to tailor management approaches that reduce the risk of hematological outcomes and hepatic complications.

Inherited polygenic effects on common hematological traits influence clonal selection on JAK2V617F and the development of myeloproliferative neoplasms.

Myeloproliferative neoplasms (MPNs) are chronic cancers characterized by overproduction of mature blood cells. Their causative somatic mutations, for example, JAK2V617F, are common in the population, yet only a minority of carriers develop MPN. Here we show that the inherited polygenic loci that underlie common hematological traits influence JAK2V617F clonal expansion. We identify polygenic risk scores (PGSs) for monocyte count and plateletcrit as new risk factors for JAK2V617F positivity. PGSs for several hematological traits influenced the risk of different MPN subtypes, with low PGSs for two platelet traits also showing protective effects in JAK2V617F carriers, making them two to three times less likely to have essential thrombocythemia than carriers with high PGSs. We observed that extreme hematological PGSs may contribute to an MPN diagnosis in the absence of somatic driver mutations. Our study showcases how polygenic backgrounds underlying common hematological traits influence both clonal selection on somatic mutations and the subsequent phenotype of cancer.

The Pitfalls of Global Hemostasis Assays in Myeloproliferative Neoplasms and Future Challenges.

Venous and arterial thromboembolism are major complications of myeloproliferative neoplasms (MPNs), comprising polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Global hemostasis assays, including thrombin generation assay (TGA), rotational thromboelastometry (ROTEM), and thromboelastography (TEG), have been proposed as biomarkers to assess the hypercoagulability and thrombotic risk stratification in MPNs. We performed a systematic literature review on the parameters of TGA, ROTEM, and TEG and their association with thrombotic events and treatment strategies in MPNs. Thirty-two studies (all cross-sectional) were included, which collectively enrolled 1,062 controls and 1,608 MPN patients. Among the 13 studies that reported arterial or venous thrombosis, the overall thrombosis rate was 13.8% with 6 splanchnic thromboses reported. Out of the 27 TGA studies, there was substantial heterogeneity in plasma preparation and trigger reagents employed in laboratory assays. There was a trend toward increased peak height among all MPN cohorts versus controls and higher endogenous thrombin potential (ETP) between ET patients versus controls. There was an overall trend toward lower ETP between PV and PMF patients versus. controls. There were no substantial differences in ETP between JAK2-positive versus JAK2-negative MPNs, prior history versus negative history of thrombotic events, and among different treatment strategies. Of the three ROTEM studies, there was a trend toward higher maximum clot firmness and shorter clot formation times for all MPNs versus controls. The three TEG studies had mixed results. We conclude that the ability of parameters from global hemostasis assays to predict for hypercoagulability events in MPN patients is inconsistent and inconclusive. Further prospective longitudinal studies are needed to validate these biomarker tools so that thrombotic potential could be utilized as a primary endpoint of such studies.

Clinical and pathological features of clonal cytopenia of undetermined significance presenting with isolated thrombocytopenia (CCUS-IT).

BACKGROUND: Clonal cytopenia of undetermined significance (CCUS) is defined as somatic mutations of myeloid malignancy-associated genes in the blood or bone marrow with one or more persistent unexplained cytopenias that do not meet diagnostic criteria for a defined myeloid neoplasm. CCUS with isolated thrombocytopenia (CCUS-IT) is rare. METHODS: This is a retrospective case series of patients with prolonged isolated thrombocytopenia, a pathogenic mutation on a myeloid molecular panel, and a bone marrow biopsy with morphologic atypia below the WHO-defined diagnostic threshold for dysplasia. RESULTS: Five male patients were identified with a median age at CCUS-IT diagnosis of 61 years (56-74). Median duration of thrombocytopenia prior to CCUS-IT diagnosis was 4 years (3-12), and median platelet count at CCUS-IT diagnosis was 41 × 103 /µL (26-80). All patients had megakaryocytic hyperplasia and megakaryocytes with hyperchromasia and high nuclear-cytoplasmic ratio. Pathogenic SRSF2 mutations were identified in all 5 patients with median variant allele frequency of 36% (28%-50%). Three patients were treated with IVIg and/or steroids with no response; one of three responded to thrombopoietin receptor agonists. Three patients progressed to MDS and one to AML. DISCUSSION: We describe the clinicopathological features of CCUS-IT which can mimic immune thrombocytopenia.

Progression in Myeloid Neoplasms: Beyond the Myeloblast.

Disease progression in myelodysplastic syndromes (MDS), myelodysplastic-myeloproliferative neoplasms (MDS/MPN), and myeloproliferative neoplasms (MPN), altogether referred to as myeloid neoplasms (MN), is a major source of mortality. Apart from transformation to acute myeloid leukemia, the clinical progression of MN is mostly due to the overgrowth of pre-existing hematopoiesis by the MN without an additional transforming event. Still, MN may evolve along other recurrent yet less well-known scenarios: (1) acquisition of MPN features in MDS or (2) MDS features in MPN, (3) progressive myelofibrosis (MF), (4) acquisition of chronic myelomonocytic leukemia (CMML)-like characteristics in MPN or MDS, (5) development of myeloid sarcoma (MS), (6) lymphoblastic (LB) transformation, (7) histiocytic/dendritic outgrowths. These MN-transformation types exhibit a propensity for extramedullary sites (e.g., skin, lymph nodes, liver), highlighting the importance of lesional biopsies in diagnosis. Gain of distinct mutations/mutational patterns seems to be causative or at least accompanying several of the above-mentioned scenarios. MDS developing MPN features often acquire MPN driver mutations (usually JAK2), and MF. Conversely, MPN gaining MDS features develop, e.g., ASXL1, IDH1/2, SF3B1, and/or SRSF2 mutations. Mutations of RAS-genes are often detected in CMML-like MPN progression. MS ex MN is characterized by complex karyotypes, FLT3 and/or NPM1 mutations, and often monoblastic phenotype. MN with LB transformation is associated with secondary genetic events linked to lineage reprogramming leading to the deregulation of ETV6, IKZF1, PAX5, PU.1, and RUNX1. Finally, the acquisition of MAPK-pathway gene mutations may shape MN toward histiocytic differentiation. Awareness of all these less well-known MN-progression types is important to guide optimal individual patient management.

Pitfalls of using polymerase chain reaction-based assays for JAK2 and CALR exon 9 variant testing in myeloproliferative neoplasms: Knowing when to go the extra mile!

OBJECTIVES: The BCR::ABL1 negative myeloproliferative neoplasms are sequentially tested for JAK2 p.V617F, followed by CALR exon 9 pathogenic variants. Historically, these variants were thought to be mutually exclusive. However, recent reports indicate coexisting JAK2 p.V617F and CALR exon 9 somatic variants. METHODS: Analysis of JAK2 p.V617F and CALR exon 9 variant was performed by polymerase chain reaction (PCR)-based assays. Subsequent testing was performed on the Genexus integrated sequencer (ThermoFisher) using the Oncomine myeloid assay GX v2. RESULTS: CALR exon 9 variants were positive in 3 cases, while 2 were positive for JAK2 p.V617F on PCR-based assays. Next-generation sequencing confirmed the JAK2 P.V617F status in all cases. CALR variants resulting in in-frame deletions were identified in 2 cases at a variant allele frequency of 52.16% and 50.91%, while the third case had an intronic CALR variant c.-48G>A at a variant allele frequency of 51.1%. Thus, CALR variants in all 3 cases were interpreted as potentially germline. Of the 228 cases that underwent JAK2 p.V617F and CALR cotesting in the past 2 years, only these 2 cases were positive for both JAK2 p.V617F and CALR exon 9 variants. CONCLUSIONS: These cases highlight the importance of understanding the pitfalls of molecular techniques in current practice.

Fifth Edition of the World Health Classification of Tumors of the Hematopoietic and Lymphoid Tissue: Myeloid Neoplasms.

In this manuscript, we review myeloid neoplasms in the fifth edition of the World Health Organization classification of hematolymphoid tumors (WHO-HEM5), focusing on changes from the revised fourth edition (WHO-HEM4R). Disease types and subtypes have expanded compared with WHO-HEM4R, mainly because of the expansion in genomic knowledge of these diseases. The revised classification is based on a multidisciplinary approach including input from a large body of pathologists, clinicians, and geneticists. The revised classification follows a hierarchical structure allowing usage of family (class)-level definitions where the defining diagnostic criteria are partially met or a complete investigational workup has not been possible. Overall, the WHO-HEM5 revisions to the classification of myeloid neoplasms include major updates and revisions with increased emphasis on genetic and molecular drivers of disease. The most notable changes have been applied to the sections of acute myeloid leukemia and myelodysplastic neoplasms (previously referred to as myelodysplastic syndrome) with incorporation of novel, disease-defining genetic changes. In this review we focus on highlighting the updates in the classification of myeloid neoplasms, providing a comparison with WHO-HEM4R, and offering guidance on how the new classification can be applied to the diagnosis of myeloid neoplasms in routine practice.

The molecular landscape of myeloproliferative neoplasms associated with splanchnic vein thrombosis: Current perspective.

BCR::ABL1-negative myeloproliferative neoplasms (MPNs) are classically represented by polycythemia vera, essential thrombocythemia, and primary myelofibrosis. BCR::ABL1-negative MPNs are significantly associated with morbidity and mortality related to an increased risk of thrombo-hemorrhagic events. They show a consistent association with splanchnic vein thrombosis (SVT), either represented by the portal, mesenteric or splenic vein thrombosis, or Budd-Chiari Syndrome. SVT is also a frequent presenting manifestation of MPN. MPNs associated with SVT show a predilection for younger women, high association with JAK2V617F mutation, low JAK2V617F variant allele frequency (generally <10 %), and low rates of CALR, MPL, or JAK2 exon 12 mutations. Next-Generation Sequencing techniques have contributed to deepening our knowledge of the molecular landscape of such cases, with potential diagnostic and prognostic implications. In this narrative review, we analyze the current perspective on the molecular background of MPN associated with SVT, pointing as well future directions in this field.

Clinical Utility and Reimbursement of Next-Generation Sequencing-Based Testing for Myeloid Malignancies.

Next-generation sequencing is becoming increasingly important for the diagnosis, risk stratification, and management of patients with established or suspected myeloid malignancies. These tests are being incorporated into clinical practice guidelines and many genetic alterations now constitute disease classification criteria. However, the reimbursement for these tests is uncertain. This study analyzed the clinical impact, ordering practices, prior authorization, and reimbursement outcomes of 505 samples from 477 patients sequenced with a 50-gene myeloid next-generation sequencing panel or a 15-gene myeloproliferative neoplasm subpanel. Overall, 98% (496 of 505) of tests provided clinically useful data. Eighty-nine percent of test results, including negative findings, informed or clarified potential diagnoses, 94% of results informed potential prognoses, and 19% of tests identified a potential therapeutic target. Sequencing results helped risk-stratify patients whose bone marrow biopsy specimens were inconclusive for dysplasia, monitor genetic evolution associated with disease progression, and delineate patients with mutation-defined diagnoses. Despite the clinical value, prior authorization from commercial payors or managed government payors was approved for less than half (45%) of requests. Only 51% of all cases were reimbursed, with lack of medical necessity frequently cited as a reason for denial. This study demonstrates the existence of a substantial gap between clinical utility and payor policies on test reimbursement.

Analytical Validation of an Automated Semiconductor-Based Next-Generation Sequencing Assay for Detection of DNA and RNA Alterations in Myeloid Neoplasms.

Myeloid neoplasms are heterogeneous tumors derived from early hematopoietic progenitors. Most international guidelines, including the European LeukemiaNet 2022 update, recommend testing a comprehensive set of genes, most within a 3- to 5-day period for optimal treatment decisions. Next-generation sequencing gene panels are essential for identifying genetic alterations, risk stratification, and determining targeted therapies for myeloid malignancies. This study describes the analytical validation of the Oncomine Myeloid Assay GX v2 (Myeloid GX v2) in combination with the Ion Torrent Genexus System using commercial controls, 16 variant-negative samples, and 130 clinical samples of myeloid neoplasms. The Myeloid GX v2 panel detected single nucleotide variants (SNVs), insertions/deletions (indels) (allele frequency >5%), and gene fusions (minimum 11 fusion copies/µL) in synthetic controls with a sensitivity of 100%. Specificity for detection of SNVs, indels, or fusions in 16 variant-negative samples was 100%. Sensitivity for detection of SNVs, indels, and gene fusions in 130 clinical samples was 99%, 97%, and 100%, respectively. Overall precision was 100% for SNVs, 96% for indels, and 100% for fusions. The average turnaround time from nucleic acid extraction to results was 2 days. The Myeloid GX v2 panel is highly accurate and reproducible for the detection of SNVs, indels, and gene fusions in myeloid neoplasms. The ability to deliver clinically relevant results in a short time is key to providing personalized treatments.