The 2016 WHO classification and diagnostic criteria for myeloproliferative neoplasms: document summary and in-depth discussion

A Novel IL3-ETV6 Fusion in Chronic Eosinophilic Leukemia Not Otherwise Specified With t(5; 12) (q31; p13): A Case Report and Literature Review

Chronic eosinophilic leukemia not otherwise specified (CEL-NOS) is classified as Myeloproliterative Neoplasms (MPN) and refers to chronic eosinophilic leukemia with some atypical recurrent genetic evidence(1). A rare fusion of ACSL6-ETV6 was previously identified in patients with the t(5;12) (q31; p13) karyotype(2). Here, we report a case of CEL-NOS with a translocation of t(5;12) (q31; p13) and identify IL3-ETV6 transcription, which has not been identified in hematologic diseases. In this patient, eosinophilia was observed. And compared with CEL-NOS patients without ETV6 fusion, a higher mRNA expression level of IL3 was found. After failing treatment with dasatinib, the patient was given hydroxyurea (HU). Subsequently his white blood cell (WBC) and eosinophils decreased significantly and remained in the normal range until publication. Due to the side effects, treatment with HU was replaced by PEG-interferon (PEG-IFN). What’s more, we summarized the case in our study and 21 patients with the karyotype of t(5; 12) (q31; p13) reported by other groups. It was found that most of them had similar clinical manifestations of eosinophilia and tyrosine kinase inhibitor (TKI) insensitivity. The ectopic mRNA expression of IL3 may be the main cause of eosinophilia, and HU and prednisone acetate (PAT), as well as IFN, were considered treatments for this group.

Digital Droplet PCR in Hematologic Malignancies: A New Useful Molecular Tool

Digital droplet PCR (ddPCR) is a recent version of quantitative PCR (QT-PCR), useful for measuring gene expression, doing clonality assays and detecting hot spot mutations. In respect of QT-PCR, ddPCR is more sensitive, does not need any reference curve and can quantify one quarter of samples already defined as "positive but not quantifiable". In the IgH and TCR clonality assessment, ddPCR recapitulates the allele-specific oligonucleotide PCR (ASO-PCR), being not adapt for detecting clonal evolution, that, on the contrary, does not represent a pitfall for the next generation sequencing (NGS) technique. Differently from NGS, ddPCR is not able to sequence the whole gene, but it is useful, cheaper, and less time-consuming when hot spot mutations are the targets, such as occurs with IDH1, IDH2, NPM1 in acute leukemias or T315I mutation in Philadelphia-positive leukemias or JAK2 in chronic myeloproliferative neoplasms. Further versions of ddPCR, that combine different primers/probes fluorescences and concentrations, allow measuring up to four targets in the same PCR reaction, sparing material, time, and money. ddPCR is also useful for quantitating BCR-ABL1 fusion gene, WT1 expression, donor chimerism, and minimal residual disease, so helping physicians to realize that "patient-tailored therapy" that is the aim of the modern hematology.

Molecular Pathogenesis of Myeloproliferative Neoplasms: From Molecular Landscape to Therapeutic Implications

Despite distinct clinical entities, the myeloproliferative neoplasms (MPN) share morphological similarities, propensity to thrombotic events and leukemic evolution, and a complex molecular pathogenesis. Well-known driver mutations, JAK2, MPL and CALR, determining constitutive activation of JAK-STAT signaling pathway are the hallmark of MPN pathogenesis. Recent data in MPN patients identified the presence of co-occurrence somatic mutations associated with epigenetic regulation, messenger RNA splicing, transcriptional mechanism, signal transduction, and DNA repair mechanism. The integration of genetic information within clinical setting is already improving patient management in terms of disease monitoring and prognostic information on disease progression. Even the current therapeutic approaches are limited in disease-modifying activity, the expanding insight into the genetic basis of MPN poses novel candidates for targeted therapeutic approaches. This review aims to explore the molecular landscape of MPN, providing a comprehensive overview of the role of drive mutations and additional mutations, their impact on pathogenesis as well as their prognostic value, and how they may have future implications in therapeutic management.

Correlations Between the Expression of Stromal Cell Activation Related Biomarkers, L-NGFR, Phospho-ERK1-2 and CXCL12, and Primary Myelofibrosis Progression

In myelofibrosis, pathologically enhanced extracellular matrix production due to aberrant cytokine signalling and clonal megakaryocyte functions result(s) in impaired hemopoiesis. Disease progression is still determined by detecting reticulin and collagen fibrosis with Gomori’s silver impregnation. Here, we tested whether the expression growth related biomarkers L-NGFR/CD271, phospho-ERK1-2 and CXCL12 can be linked to the functional activation of bone marrow stromal cells during primary myelofibrosis progression. Immunoscores for all tested biomarkers showed varying strength of positive statistical correlation with the silver impregnation based myelofibrosis grades. The intimate relationship between spindle shaped stromal cells positive for all three markers and aberrant megakaryocytes was likely to reflect their functional cooperation. L-NGFR reaction was restricted to bone marrow stromal cells and revealed the whole length of their processes. Also, L-NGFR positive cells showed the most intersections, the best statistical correlations with myelofibrosis grades and the strongest interrater agreements. CXCL12 reaction highlighted stromal cell bodies and a weak extracellular staining in line with its constitutive release. Phospho-ERK1-2 reaction showed a similar pattern to CXCL12 in stromal cells with an additional nuclear staining in agreement with its role as a transcription factor. Both p-ERK1-2 and CXCL12 were also expressed at a moderate level in sinus endothelial cells. Connexin 43 gap junction communication channels, known to be required for CXCL12 release to maintain stem cell niche, were also expressed progressively in the myelofibrotic stromal network as a support of compartmental functions. Our results suggest that, diverse growth related pathways are activated in the functionally coupled bone marrow stromal cells during myelofibrosis progression. L-NGFR expression can be a useful biological marker of stromal cell activation which deserves diagnostic consideration for complementing Gomori’s silver impregnation.

The Use of Allogeneic Hematopoietic Stem Cell Transplantation in Primary Myelofibrosis

Primary myelofibrosis (PMF) is a BCR-ABL1 negative myeloproliferative neoplasm characterized by clonal proliferation of myeloid cells. This leads to reactive bone marrow fibrosis, ultimately resulting in progressive marrow failure, hepatosplenomegaly, and extramedullary hematopoiesis. PMF is considered the most aggressive of the BCR-ABL1 negative myeloproliferative neoplasms with the least favorable prognosis. Constitutional symptoms are common, which can impact an individual’s quality of life and leukemic transformation remains an important cause of death in PMF patients. The development of the Janus kinase 2 (JAK2) inhibitors have provided a good option for management of PMF-related symptoms. Unfortunately, these agents have not been shown to improve overall survival or significantly alter the course of disease. Allogenic hematopoietic stem cell transplantation (allo-HSCT) remains the only curative treatment option in PMF. However, allo-HSCT is associated with significant treatment-related morbidity and mortality and has historically been reserved for younger, high-risk patients. This review examines patient, disease, and transplant-specific factors which may impact transplant-related outcomes in PMF. Through the vast improvements in donor selection, conditioning regimens, and post-transplant care, allo-HSCT may provide a safe and effective curative option for a broader range of PMF patients in the future.

Diabetes and Second Neoplasia Impact on Prognosis in Pre-Fibrotic Primary Myelofibrosis

Simple Summary

The 2016 WHO-revised classification of MPNs recognized pre-fibrotic PMF (pre-PMF) as a distinct clinical entity from both overt fibrotic PMF (overt PMF) and essential thrombocythemia (ET). In fact, while the initial presentation of pre-PMF is often an isolated thrombocytosis, thus mimicking ET, its course may be symptomatic in a non-negligible number of cases. Conversely, overt PMF patients are enriched in higher-risk categories, thus suggesting a greater propensity for disease progression than pre-PMF. Importantly, median survival is significantly reduced in overt PMF vs. pre-PMF, thereby reinforcing the appropriateness of making this distinction in clinical practice. Nevertheless, a specific prognostic model for pre-PMF is still lacking, except for thrombotic risk. The aim of the present study was therefore to identify covariates other than those commonly related to PMF, which can better define prognosis in pre-PMF patients in the real-world setting, thus resulting in more personalized and efficient therapeutic approaches.

Abstract

The 2016 WHO classification recognized pre-fibrotic primary myelofibrosis (pre-PMF) as a distinct entity. Nevertheless, a prognostic model specific for pre-PMF is still lacking. Our aim was to identify the most relevant clinical, histological, and driver mutation information at diagnosis to evaluate outcomes in pre-PMF patients in the real-world setting. We firstly assessed the association between IPSS or DIPSS at diagnosis and response variables in 378 pre-PMF patients. A strict association was observed between IPSS and DIPSS and occurrence of death. Other analyzed endpoints were not associated with IPSS or DIPSS as thrombo-hemorrhagic events at diagnosis or during follow-up, or did not show a clinical plausibility, as transformation into acute leukemia or overt PMF. The only covariates which were significantly associated with death were diabetes and second neoplasia, and were therefore included in two different prognostic settings: the first based on IPSS at diagnosis [class 1 vs. 0, OR (95%CIs): 3.34 (1.85–6.04); class 2 vs. 0, OR (95%CIs): 12.55 (5.04–31.24)], diabetes [OR (95%CIs): 2.95 (1.41–6.18)], and second neoplasia [OR (95%CIs): 2.88 (1.63–5.07)]; the second with DIPSS at diagnosis [class 1 vs. 0, OR (95%CIs): 3.40 (1.89–6.10); class 2 vs. 0, OR (95%CIs): 25.65 (7.62–86.42)], diabetes [OR (95%CIs): 2.89 (1.37–6.09)], and second neoplasia [OR (95%CIs): 2.97 (1.69–5.24)]. In conclusion, our study underlines the importance of other additional risk factors, such as diabetes and second neoplasia, to be evaluated, together with IPSS and DIPSS, to better define prognosis in pre-PMF patients.

How I Diagnose Primary Myelofibrosis

OBJECTIVES

Primary myelofibrosis (PMF) is a BCR/ABL1-negative myeloproliferative neoplasm (MPN) with a shorter overall survival and a higher leukemic transformation than other BCR/ABL1-negative MPNs. Diagnosis of PMF can be challenging given its clinical, morphologic, molecular overlap with other myeloid neoplasms also associated with myelofibrosis, and reactive conditions.

METHODS

We summarize and discuss the clinical, morphologic, and molecular features useful for diagnosing PMF as well as salient features helpful in distinguishing PMF from myelodysplastic syndrome with associated fibrosis and autoimmune myelofibrosis using a case-based approach.

RESULTS

PMF in both its prefibrotic and fibrotic stages, the latter characterized by reticulin/collagen marrow fibrosis, is characterized by a proliferation of predominantly abnormal megakaryocytes and granulocytes in the bone marrow. Driver mutations in   JAK2, CALR, or MPLare seen in approximately 90% of PMF cases. In triple-negative cases, the presence of cytogenetic abnormalities and other somatic mutations identified by next-generation sequencing can help establish a diagnosis of PMF in the appropriate clinical and morphologic context.

CONCLUSIONS

Given the significant difference in prognosis and treatment, integration of clinical, morphological, and molecular/genetic findings is essential in distinguishing PMF from other etiologies that can demonstrate myelofibrosis.

Elevated serum IL-13 level is associated with increased Treg cells in tumor microenvironment and disease progression of Diffuse large B-cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is the most common aggressive lymphoid malignancy, with an immunosuppressive microenvironment affecting clinical outcome. Interleukin (IL)-13 overexpression is observed in multiple solid tumors and contributes to tumor progression. This study aims to investigate pretreatment serum IL-13 levels and their relationship with the prognosis of DLBCL patients. One hundred and sixty-six patients with newly diagnosed DLBCL from June 2015 to July 2017 were included. Patients with elevated pretreatment serum IL-13 levels (IL-13≥1.63pg/ml) were classified into the high IL-13 group and they had significantly lower complete remission rate (60% vs. 74%, p=0.0059), higher progression rate (43% vs. 23%, p=0.0051), and poor progression-free survival (2-yr PFS, 63% vs. 78%，p=0.0078) and overall survival (2-yr OS, 75% vs. 92%, p=0.0027), when compared to those in the low IL-13 group (IL-13<1.63pg/ml). Meanwhile, increased Treg cell ratio in peripheral blood (p=0.0147) and elevated serum IL-2 levels (p=0.0272) were observed in the high IL-13 group. Moreover, RNA sequencing data showed that patients in the high IL-13 group had significantly elevated expression of chemokines and chemokine receptors (CCR4, CCL19, CCL21, CXCL2) related to Treg activation and recruitment. Consistent with the chemokine profile, tumor immunophenotyping analysis revealed that higher Treg cells recruitment in the high IL-13 group than the low IL-13 group (p=0.0116). In vitro, when lymphoma cells co-cultured with peripheral blood monocytes of healthy controls, metformin down-regulated both IL-13 level and Treg cell ratio, in consistent with the decreased serum IL-13 levels of patients after 6 months of metformin maintenance therapy in the high IL-13 group. Taken together, pretreatment serum IL-13 level is related to the immunosuppressive microenvironment and poor clinical outcome of DLBCL patients and could be targeted by metformin, thus providing a new therapeutic strategy in treating DLBCL with high serum IL-13 levels. This article is protected by copyright. All rights reserved.

Potential limitations of diagnostic standard codes to distinguish polycythemia vera and secondary erythrocytosis

Red cell overproduction is seen in polycythemia vera (PV), a bone marrow myeloproliferative neoplasm characterized by trilinear cell proliferation (WBC, platelets), as well as in secondary erythrocytosis (SE), a group of heterogeneous disorders characterized by elevated EPO gene transcription. We aimed to verify the concordance of the International Classification of Diseases (ICD) code-based diagnosis of “polycythemia” or “erythrocytosis” with the true clinical diagnosis of these conditions. We retrospectively reviewed the electronic medical records (January 1, 2005, to December 31, 2016) of adult patients with ICD codes of polycythemia and/or erythrocytosis who had testing done for the presence of the JAK2V617F mutation. We verified the accuracy of the ICD code-based diagnoses by meticulous chart review and established whether these patients fulfilled the criteria by the evaluating physician for PV or SE and according to the World Health Organization 2016 diagnostic guidelines. The reliability of ICD coding was calculated using Cohen's kappa. We identified and chart reviewed a total of 578 patient records. Remarkably, 11% of the patients had concurrent diagnosis codes for PV and SE and were unable to be classified appropriately without individual chart review. The ICD code-based diagnostic system led to misidentification in an important fraction of cases. This represents a problem for the detection of PV or SE cases by ICD-based registries and their derived studies. Research based exclusively on ICD codes could have a potential impact on patient care and public health, and limitations must be weighed when research findings are conveyed.

Management of Myeloproliferative Neoplasms (MPNs)

PURPOSE

To provide up to date guidance, practice recommendations and highlight barriers to medication adherence in the long-term management of chronic myeloproliferative neoplasms (MPNs).

AIM

Current drug therapy for MPN is not curative and has not been shown to prolong survival. The main indication for treatment is the prevention of thrombosis and medication adherence remains a challenge in this group of patients. Identifying potentially modifiable barriers to medication adherence including primary nonadherence and non-persistent adherence enables timely interventions to be put in place and improve overall medication adherence.

METHODS

A systematic review of peer-reviewed literature and expert opinions was performed using electronic databases (PubMed, EMBASE, MEDLINE, and Web of Science) that were searched for articles reporting MPN and medication adherence. Discussions A case vignette is discussed throughout the article and expert opinion with international peer reviewed guidelines that are authored to support clinical decision making at the point of care were utilised. The evidence base was combined with more practical/clinical (data based) insight from real world clinical practice. Adoption of a broad range of digital health care activities and services in the health care system (telehealth applications) by the advanced practice providers (Non-Medical Prescribers-NMPs) in MPN clinics included medication prescribing and management, oral drug compliance and adherence evaluations, interventions, chronic care management, counselling and patient education on treatments.

CONCLUSION

Current drug therapy for MPN is neither curative nor has it been shown to prolong survival, and medication adherence remains a challenge in this group of patients. The longevity of the patients' disease course may contribute to the high risk of non-adherence in this patient cohort. Poor adherence to long-term therapies severely compromises the effectiveness of treatment. Adherence interventions should be tailored to the needs of the patient in order to achieve maximum impact. Interventions aimed at improving adherence provide the best experience and outcome for the patient and their families and can have a profound impact on the quality of life and mitigation of disease consequences.

Comparison of Clinical and Hematological Parameters of Janus Kinase 2, Calreticulin or Myeloproliferative Leukemia Virus Oncogene Mutant Essential Thrombocythemia and Triple-Negative Essential Thrombocythemia

Introduction

Essential thrombocythemia (ET) is one of the chronic myeloproliferative neoplasms. While Janus kinase 2 (JAK2) V617F mutation is defined in more than half of the patients with ET, calreticulin (CALR) or myeloproliferative leukemia virus oncogene (MPL) mutations are encountered more rarely. The discovery of the JAK2 V617F mutation in 2005, followed by the recognition of MPL and CALR mutations, brought up the idea of subdividing ET according to the mutation status. Our aim in this study is to investigate whether genetic mutations detected in patients diagnosed with ET cause a different clinical phenotype compared to triple-negative ET.

Methods

This retrospective study was conducted by evaluating the patients who were followed up with the diagnosis of ET in the hematology clinic of two tertiary centers in Turkey between 2009 and 2021. Patients with negative JAK2, CALR, and MPL mutations and meeting the diagnostic criteria for ET were defined as triple-negative ET. The patients were divided into two groups as triple-negative ET and mutation-positive ET according to the presence of a mutation. It was investigated whether there was a difference between these two groups in terms of demographic, laboratory, and clinical characteristics.

Results

A total of 109 patients were included in the study. The mean age of these patients was 54 (18-91) years and 85 (78%) patients were females. A total of 48 patients (44.0%) had JAK2 mutation, six (5.5%) had CALR mutation, and one (0.9%) had MPL mutation. It was observed that there was a significant difference between the two groups in terms of gender, mean age, and hemoglobin value. While 87% of patients with triple-negative ET were females, this rate was 69% in patients with mutation-positive ET (p = 0.036). The mean age was 41.8 years in triple-negative ET and 67.1 years in patients with mutation-positive ET (p = 0.0001). While the mean hemoglobin value was 12.9 g/dl in patients with triple-negative ET, it was 14.4 g/dl in patients with mutation-positive ET (p = 0.0001).

Conclusion

It has been observed that ET with JAK2, CALR, or MPL mutations may have different phenotypic features compared to triple-negative ET, resulting in a clinical condition consisting of older patients with a higher erythrocyte count.

The Minimal Residual Disease Using Liquid Biopsies in Hematological Malignancies

The study of cell-free DNA (cfDNA) and other peripheral blood components (known as "liquid biopsies") is promising, and has been investigated especially in solid tumors. Nevertheless, it is increasingly showing a greater utility in the diagnosis, prognosis, and response to treatment of hematological malignancies; in the future, it could prevent invasive techniques, such as bone marrow (BM) biopsies. Most of the studies about this topic have focused on B-cell lymphoid malignancies; some of them have shown that cfDNA can be used as a novel way for the diagnosis and minimal residual monitoring of B-cell lymphomas, using techniques such as next-generation sequencing (NGS). In myelodysplastic syndromes, multiple myeloma, or chronic lymphocytic leukemia, liquid biopsies may allow for an interesting genomic representation of the tumor clones affecting different lesions (spatial heterogeneity). In acute leukemias, it can be helpful in the monitoring of the early treatment response and the prediction of treatment failure. In chronic lymphocytic leukemia, the evaluation of cfDNA permits the definition of clonal evolution and drug resistance in real time. However, there are limitations, such as the difficulty in obtaining sufficient circulating tumor DNA for achieving a high sensitivity to assess the minimal residual disease, or the lack of standardization of the method, and clinical studies, to confirm its prognostic impact. This review focuses on the clinical applications of cfDNA on the minimal residual disease in hematological malignancies.

Myeloproliferative Syndrome With Eosinophilia Associated With Translocation t(8; 13) and T-cell Lymphoblastic Lymphoma: A Case Report and Review of the Literature

The 8p11 myeloproliferative syndrome (EMS) is an aggressive neoplasm associated with chromosomal translocations involving the fibroblast growth factor receptor 1 tyrosine kinase gene on chromosome 8p11. We report the case of a 31-year-old man with no prior medical history who presents with two weeks of sore throat and cervical lymphadenopathy up to 5 cm. Initial peripheral blood examination showed leukocytosis with predominantly neutrophils and eosinophilia. A CT scan demonstrated mediastinal lymphadenopathies, liver enlargement and splenomegaly. An excisional biopsy of a cervical lymph node demonstrated findings consistent with a diagnosis of T-cell lymphoblastic lymphoma. Bone marrow aspirate and biopsy revealed hypercellular marrow with granulocytic predominance, left-shifted granulopoiesis, eosinophilia and the cytogenetic analysis showed the following karyotype: 46, XY, t(8;13). The final diagnosis was a myeloproliferative syndrome with eosinophilia related to t(8;13) and T-cell acute lymphoblastic lymphoma (8p11 myeloproliferative syndrome). We review the relevant literature about this unusual entity.

Primary Myelofibrosis in the Prefibrotic Stage Presenting as Portal, Splenic, and Superior Mesenteric Vein Thrombosis: A Case Report and Review of the Literature

INTRODUCTION

Myeloproliferative neoplasms are the most common cause of splanchnic vein thrombosis in the absence of cirrhosis or nearby malignancy.

CASE PRESENTATION

A 31-year-old male presented to the emergency department with epigastric pain associated with mild thrombocytosis and elevated levels of aminotransferases, lactate dehydrogenase, and C-reactive protein. Contrast-enhanced abdominal computed tomography revealed splanchnic venous thrombosis that involved the portal, splenic, and superior mesenteric veins, without signs of chronic liver disease. Anticoagulation with warfarin was immediately started. Diagnostic work-up was remarkable for the presence of the JAK2 V617T mutation and hypercellular bone marrow, with increased myeloid cells and atypical megakaryocytes, consistent with primary myelofibrosis in a prefibrotic stage. No other hypercoagulable conditions were identified.

DISCUSSION

We present a rare case of primary myelofibrosis in the prefibrotic stage presenting as portal-splenic-superior mesenteric vein thrombosis. This demonstrates that extensive splanchnic vein thrombosis may be the onset manifestation of myeloproliferative neoplasms, even in early stages and in the absence of concomitant hypercoagulable conditions. The presence of the JAK2 mutation is an important prothrombotic risk factor that can, per se, contribute to large venous thrombosis.

Tropical Fever Unveiling an Asymptomatic Case of Polycythemia Vera

We report a case of fulminant hepatic failure due to the Budd–Chiari syndrome following preservation with a tropical fever. A young lady came with fever, altered mental status, jaundice, and renal failure. Following tropical workup, it was diagnosed as a case of leptospirosis (WHO Faine's criteria) with multi-organ dysfunction. Despite adequate antimicrobial cover, she progressed to hepatic coma (hyperammonemia) and was noted to have worsening conjugated hyperbilirubinemia. Following history review and evaluation for other causes of hepatic failure, hepatic vein thrombosis was detected in addition to the presence of antibodies against Leptospira antigen. Further studies into the causes of thrombosis and persistent hemoconcentration despite aggressive fluid resuscitation led to the diagnosis of polycythemia vera (cytometric analysis). During her stay, she further worsened despite aggressive organ support including dialysis but she succumbed to gram-negative sepsis that occurred during her stay in ICU. This is an interesting and rare case of leptospirosis that unveiled a case of previously asymptomatic polycythemia vera.

How I manage myeloproliferative neoplasm-unclassifiable: Practical approaches for 2022 and beyond

Myeloproliferative neoplasm (MPN)-unclassifiable (MPN-U) or not otherwise specified represents a rare, poorly defined and heterogeneous group of MPNs. Disease incidence is difficult to define but likely represents close to 5% of all MPNs when strict World Health Organisation (WHO) criteria are applied. Dynamic review over time is required to assess if the disease can be re-classified into another MPN entity. A diagnosis of MPN-U leads to many challenges for both the patient and physician alike including lack of agreed monitoring and therapeutic guidelines, validated prognostic markers and licenced therapies coupled with exclusion from clinical trials. MPN-U has an inherent risk of an aggressive clinical course and transformation in some but who, and when to treat in the chronic phase, including identifying who may require more aggressive therapy at an earlier stage, remains elusive. Moreover, despite the significant thrombotic risk, there is no agreement on systematic primary thromboprophylaxis. We hereby provide a contemporary overview of MPN-U in addition to four illustrative cases providing our collective suggested approaches to clinical challenges.

Immunohistopathological Analysis of Extramedullary Hematopoiesis and Angiogenesis of Spleen in a Case of Primary Myelofibrosis with Huge Splenomegaly

Although splenomegaly is one of the important signs of primary myelofibrosis, the differential diagnosis varies from malignant disorders to benign disorders, including malignant lymphoma and sarcoidosis. The patient was a 67-year-old male who developed anemia and huge splenomegaly. The laboratory findings include human T-cell leukemia virus type 1 (HTLV-1) antibody, elevated soluble interleukin-2 receptor, hypocellular bone marrow, and uptake in the spleen on positron emission tomography/computed tomography scan. Additionally, we performed laparoscopic splenectomy to alleviate the clinical symptoms and to rule out malignant lymphoma. Histological findings revealed extramedullary hematopoiesis, characterized by the presence of erythroid islands and clusters of dysplastic megakaryocytes with increased reticulin fibrosis. Immunohistochemical staining revealed the presence of von Willebrand factor, dysplastic megakaryocytes, myeloperoxidase, myeloid-predominant proliferations, and CD34 immature myeloid cells. Furthermore, regarding the angiogenesis in the spleen, the endothelial cells of the capillaries and those of the sinusoidal vascular system that were reactive for CD34 and CD8, respectively, were also detected. Consequently, the histological findings revealed both extramedullary hematopoiesis and angiogenesis in spleen. Based on the histological findings and the identification of Janus activating kinase 2 (JAK-2) mutation, the patient was diagnosed with primary myelofibrosis. Splenectomy reduces blood transfusion requirements after surgery. The patient was carefully followed-up without further treatments. Thus, primary myelofibrosis is the crucial differential diagnosis of huge splenomegaly.

Oncogenic and tumor suppressor genes expression in myeloproliferative neoplasms: The hidden side of a complex pathology

Background

The present study aimed to explore the changes in the expressions of six tumor‐related genes in myeloproliferative neoplasms (MPNs). The study population included 130 patients with MPNs (52 with chronic myeloid leukemia (CML), 49 with essential thrombocythemia (ET), 20 with polycythemia vera (PV), and 9 with primary myelofibrosis (PMF)) and 51 healthy individuals.

Methods

The expression profiling of six genes (ADAMTS18, CMTM5, CDKN2B, DCC, FHIT, and WNT5B) in the peripheral blood granulocyte cells was explored by real‐time quantitative reverse transcription polymerase chain reaction.

Results

The patients with MPNs showed significant downregulation of CMTM5 (EFC = 0.66) and DCC (EFC = 0.65) genes in contrast to a non‐significant upregulation of ADAMTS18, CDKN2B, FHIT, and WNT5B genes. Downregulation of DCC was consistent in all subtypes of MPN (EFC range: 0.591–0.860). However, CMTM5 had a 1.22‐fold upregulation in PMF in contrast to downregulation in other MPN subtypes (EFC range: 0.599–0.775). The results revealed a significant downregulation in CMTM5 and DCC at below 60‐years of age. Furthermore, female patients showed a clear‐cut downregulation in both CMTM5 and DCC (EFC DCC: 0.436 and CMTM5: 0.570), while male patients presented a less prominent downregulation with a borderline p‐value only in DCC (EFC: 0.69; p = 0.05).

Conclusions

Chronic myeloid leukemia cases showed a significant upregulation of WNT5B, as a known oncogenesis gene. Two tumor suppressor genes, namely DCC and CMTM5, were downregulated in the patients with MPNs, especially in females and patients below 60 years of age.

Red Blood Cell Morphodynamics in Patients with Polycythemia Vera and Stroke

Polycythemia vera (PV) is a Ph-negative myeloproliferative neoplasm (MPN) which is characterized by erythrocytosis and a high incidence of thrombotic complications, including stroke. The study aimed to evaluate red blood cell (RBC) morphodynamic properties in PV patients and their possible association with stroke. We enrolled 48 patients with PV in this cross-sectional study, 13 of which have a history of ischemic stroke. The control group consisted of 90 healthy subjects. RBC deformability and aggregation analysis were performed using a laser-assisted optical rotational red cell analyzer. The following parameters were calculated: aggregation amplitude (Amp), RBC rouleaux formation time constant (Tf), time of formation of three-dimensional aggregates (Ts), aggregation index (AI), rate of complete disaggregation (y-dis), and the maximal elongation of RBC (EImax). Statistical analysis was performed with the R programming language. There were significant differences in RBCs morphodynamics features between patients with PV and the control group. Lower EImax (0.47 (0.44; 0.51) vs. 0.51 (0.47; 0.54), p < 0.001) and γ-dis (100 (100; 140) vs. 140 (106; 188) s⁻¹, p < 0.001) along with higher amplitude (10.1 (8.6; 12.2) vs. 7.7 (6.6; 9.2), p < 0.001) was seen in patients with PV compared with control. A statistically significant difference between PV patients with and without stroke in aggregation amplitude was found (p = 0.03). A logistic regression model for stroke was built based on RBC morphodynamics which performed reasonably well (p = 0.01). RBC alterations may be associated with overt cerebrovascular disease in PV, suggesting a possible link between erythrocyte morphodynamics and increased risk of stroke.

JAK2 Variant Signaling: Genetic, Hematologic and Immune Implication in Chronic Myeloproliferative Neoplasms

The JAK2V617F variant constitutes a genetic alteration of higher frequency in BCR/ABL1 negative chronic myeloproliferative neoplasms, which is caused by a substitution of a G ˃ T at position 1849 and results in the substitution of valine with phenylalanine at codon 617 of the polypeptide chain. Clinical, morphological and molecular genetic features define the diagnosis criteria of polycythemia vera, essential thrombocythemia and primary myelofibrosis. Currently, JAK2V617F is associated with clonal hematopoiesis, genomic instability, dysregulations in hemostasis and immune response. JAK2V617F clones induce an inflammatory immune response and lead to a process of immunothrombosis. Recent research has shown great interest in trying to understand the mechanisms associated with JAK2V617F signaling and activation of cellular and molecular responses that progressively contribute to the development of inflammatory and vascular conditions in association with chronic myeloproliferative neoplasms. Thus, the aim of this review is to describe the main genetic, hematological and immunological findings that are linked to JAK2 variant signaling in chronic myeloproliferative neoplasms.

JAK2 inhibitor persistence in MPN: uncovering a central role of ERK activation

The Philadelphia chromosome negative myeloproliferative neoplasms, including polycythemia vera, essential thrombocytosis, and myelofibrosis, are driven by hyper activation of the JAK2 tyrosine kinase, the result of mutations in three MPN driving genes: JAK2, MPL, and CALR. While the anti-inflammatory effects of JAK2 inhibitors can provide improved quality of life for many MPN patients, the upfront and persistent survival of disease-driving cells in MPN patients undergoing JAK2 inhibitor therapy thwarts potential for remission. Early studies indicated JAK2 inhibitor therapy induces heterodimeric complex formation of JAK2 with other JAK family members leading to sustained JAK2-dependent signaling. Recent work has described novel cell intrinsic details as well as cell extrinsic mechanisms that may contribute to why JAK2 inhibition may be ineffective at targeting MPN driving cells. Diverse experimental strategies aimed at uncovering mechanistic details that contribute to JAK2 inhibitor persistence have each highlighted the role of MEK/ERK activation. These approaches include, among others, phosphoproteomic analyses of JAK2 signaling as well as detailed assessment of JAK2 inhibition in mouse models of MPN. In this focused review, we highlight these and other studies that collectively suggest targeting MEK/ERK in combination with JAK2 inhibition has the potential to improve the efficacy of JAK2 inhibitors in MPN patients. As MPN patients patiently wait for improved therapies, such studies should further strengthen optimism that pre-clinical research is continuing to uncover mechanistic insights regarding the ineffectiveness of JAK2 inhibitors, which may lead to development of improved therapeutic strategies.

Osteolytic bone lesions in patients with primary myelofibrosis: A systematic review

Philadelphia negative myeloproliferative neoplasms (MPNs) are classically characterized by excess production of terminal myeloid cells in the peripheral blood. They include polycythemia vera, essential thrombocythemia, and primary myelofibrosis. Among this group, primary myelofibrosis is the least common and usually carries the worst prognosis. Bone involvement in primary myelofibrosis has many forms; it affects bone marrow leading to bone marrow fibrosis, it can cause periostitis, in addition to bone and joint pain. A common radiologic finding in primary myelofibrosis is the presence of osteosclerotic lesions. However, the presence of osteolytic lesions in bone imaging was described in few reports. In this review, we searched English literature using the PRISMA guidelines looking for patients with Primary myelofibrosis who had osteolytic bone lesions to assess the impact of such findings on the disease and its effect on prognosis. We found the vast majority of lesions were painful affecting most commonly the vertebral column, pelvis, and ribs, and were detected in patients above 50 years of age with no gender preference, unfortunately they represented advanced disease stages, resulting in inadequate treatment response and poor outcome.

JAK2 allele burden is correlated with a risk of venous but not arterial thrombosis

BACKGROUND

Thrombosis is the main complication in myeloproliferative neoplasms (MPN). A JAK2V617F mutation has been shown to be a risk factor for thrombosis. The implication of other risk factors alongside a mutation allele burden needs to be clarified (Trifa et al., 2018; Borowczyk et al., 2015).

OBJECTIVE

Our aim was to investigate the role of the JAK2 mutation allele burden in the risk of cardiovascular events (CVE) and/or venous thrombosis (VTE) in a cohort of patients with confirmed MPN, as well as in patients without confirmed MPN.

METHODS

We restrospectively included all consecutive patients who were positive for JAK2V617F seen by our unit between December 2008 and September 2016. Inclusion criteria were a positive test for the JAK2V617F mutation, with at least 1% allele burden, with or without confirmed MPN.

RESULTS

We included 239 patients of median age 71 years [60-81], followed-up for a median of 82.8 months [41.08-146.88]. For JAK2V617F positive patients having an allele burden superior to 50% the cumulative incidence of VTE was significantly higher than for those with an allele burden inferior to 50% (HR 3.11 95% CI [1.10-8.76] p = 0.031). The cumulative incidence of VTE was also higher in patients with obesity (HR 4.58 95% CI [1.33-15.8] p = 0.016). There was no significant association between a JAK2V617F allele burden and arterial thrombosis (manifesting as CVE). Previous VTE was also associated with a higher cumulative incidence of recurrence during follow-up HR 3.22 95% CI [1.17-8.81] p = 0.0231.

CONCLUSION

We show that a JAK2V617F allele burden is associated with risk of VTE but not with CVE.

Importance of Sequencing HBA1, HBA2 and HBB Genes to Confirm the Diagnosis of High Oxygen Affinity Hemoglobin

High oxygen affinity hemoglobin (HOAH) is the main cause of constitutional erythrocytosis. Mutations in the genes coding the alpha and beta globin chains (HBA1, HBA2 and HBB) strengthen the binding of oxygen to hemoglobin (Hb), bringing about tissue hypoxia and a secondary erythrocytosis. The diagnosis of HOAH is based upon the identification of a mutation in HBA1, HBA2 or HBB in specialized laboratories. Phenotypic studies of Hb are also useful, but electrophoretic analysis can be normal in 1/3 of cases. The establishment of the dissociation curve of Hb can be used as another screening test, a shift to the left indicating an increased affinity for Hb. The direct measurement of venous P50 using a Hemox Analyzer is of great importance, but due to specific analytic conditions, it is only available in a few specialized laboratories. Alternatively, an estimated measurement of the P50 can be obtained in most of the blood gas analyzers on venous blood. The aim of our study was therefore to determine whether a normal venous P50 value could rule out HOAH. We sequenced the HBB, HBA1 and HBA2 genes of 75 patients with idiopathic erythrocytosis. Patients had previously undergone an exhaustive medical check-up after which the venous P50 value was defined as normal. Surprisingly, sequencing detected HOAH in three patients (Hb Olympia in two patients, and Hb St Nazaire in another). A careful retrospective examination of their medical files revealed that (i) one of the P50 samples was arterial; (ii) there was some air in another sample; and (iii) the P50 measurement was not actually done in one of the patients. Our study shows that in real life conditions, due to pre-analytical contingencies, a venous P50 value that is classified as being normal may not be sufficient to rule out a diagnosis of HOAH. Therefore, we recommend the systematic sequencing of the HBB, HBA1 and HBA2 genes in the exploration of idiopathic erythrocytosis.

Assessing Bone Marrow Activity with [18F]FLT PET in Patients with Essential Thrombocythemia and Prefibrotic Myelofibrosis: A Proof of Concept

Objectives: This study aims to assess the value of FLT-PET as a non-invasive tool to differentiate between patients with ET and Pre-PMF. This study is a pilot study to have a proof of concept only. Methods: This is a prospective, interventional study where a total of 12 patients were included. Each patient underwent FLT PET imaging as well as bone marrow examination (gold standard). In addition, semi-quantitative (SUVmax and SUVmean) measurements of FLT uptake in the liver, spleen, and Lspine, SUVmean, as well as the Total Lesion Glycolysis (TLG) of the Lspine were performed. Results from the two patient cohorts were compared using = Kruskal-Wallis statistical test. A P-value of <.05 is considered to be statistically significant. Results: The differences in FLT SUVmax and SUVmean measurements in the three organs (liver, spleen, and LSpine) between the ET and Pre-PMF patients were not statistically significant (P > .05). In contrast, TLG measurements in the LSpine were statistically different (P = .013), and therefore, compared to gold standard bone marrow results, TLG can separate ET and Pre-PMF patients. Conclusion: This study is a proof of concept about the potential to discriminate between ET and pre-PMF patients in a non-invasive way. TLG of the LSpine in FLT PET images is a potential quantitative parameter to distinguish between ET and pre-PMF patients.

Patients with MPNs and retinal drusen show signs of complement system dysregulation and a high degree of chronic low-grade inflammation

BACKGROUND

The hematopoietic stem cell disorders, myeloproliferative neoplasms (MPNs), are characterised by chronic low-grade inflammation (CLI). Recently, we showed that patients with MPNs have an increased prevalence of drusen and age-related macular degeneration (AMD), and drusen prevalence seemed associated with higher CLI. Studying MPNs may reveal more about drusen pathophysiology. This study investigated CLI further by measuring cytokine levels and complement system markers, comparing these between patients with MPNs and AMD.

METHODS

This cross-sectional study, between July 2018 and November 2020 conducted at Zealand University Hospital (ZUH) - Roskilde, Denmark, included 29 patients with neovascular AMD (nAMD), 28 with intermediate-stage AMD (iAMD), 62 with MPNs (35 with drusen - MPNd and 27 with healthy retinas - MPNn). With flow cytometry, we measured complement-regulatory-proteins (Cregs). With immunoassays, we investigated cytokine levels combined into a summary-inflammation-score (SIS).

FINDINGS

The MPNd and nAMD groups had similar SIS, significantly higher than the MPNn and iAMD groups. Additionally, we found SIS to increase over the MPN biological continuum from early cancer stage, essential thrombocytaemia (ET), over polycythaemia vera (PV) to the late-stage primary myelofibrosis (PMF). MPNs showed signs of complement dysregulation, with Cregs expression lower in PV than ET and PMF and even lower in PV patients with drusen.

INTERPRETATION

This study suggests that MPNd have a higher CLI than MPNn and may indicate systemic CLI to play a greater part in, and even initiate drusen formation. We suggest using MPNs as a "Human Inflammation Model" of drusen development. The CLI in MPNs elicits drusen formation, triggering more CLI creating a vicious cycle, increasing the risk of developing AMD.

FUNDING

Fight for Sight, Denmark, and Region Zealand's research promotion fund.

Updated recommendations on the use of ruxolitinib for the treatment of myelofibrosis

OBJECTIVES

Myelofibrosis is a rare bone marrow disorder associated with a high symptom burden, poor prognosis, and shortened survival. While allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for myelofibrosis, the only approved and reimbursed pharmacotherapy for non-HSCT candidates in Belgium is ruxolitinib.

METHODS

These updated recommendations are based on a consensus reached during two meetings and provide guidance for ruxolitinib administration in myelofibrosis patients considering the particularities of Belgian reimbursement criteria.

RESULTS AND DISCUSSION

In Belgium, ruxolitinib is indicated and reimbursed for transplant-ineligible myelofibrosis patients from intermediate-2- and high-risk groups and from the intermediate-1-risk group with splenomegaly. Our recommendation is to also make ruxolitinib available in the pre-transplant setting for myelofibrosis patients with splenomegaly or heavy symptom burden. Before ruxolitinib initiation, complete blood cell counts are recommended, and the decision on the optimal dosage should be based on platelet count and clinical parameters. In anemic patients, we recommend starting doses of ruxolitinib of 10 mg twice daily for 12 weeks and we propose the use of erythropoiesis-stimulating agents in patients with endogenous erythropoietin levels ≤500 mU/mL. Increased vigilance for opportunistic infections and second primary malignancies is needed in ruxolitinib-treated myelofibrosis patients. Ruxolitinib treatment should be continued as long as there is clinical benefit (reduced splenomegaly or symptoms), and we recommend progressive dose tapering when stopping ruxolitinib.

CONCLUSION

Based on new data and clinical experience, the panel of experts discussed ruxolitinib treatment in Belgian myelofibrosis patients with a focus on dose optimization/monitoring, adverse events, and interruption/rechallenge management.

Retinal drusen in patients with chronic myeloproliferative blood cancers are associated with an increased proportion of senescent T cells and signs of an aging immune system

The cause of age-related macular degeneration (AMD) is unknown, but evidence indicates that both innate and adaptive immunity play a role in the pathogenesis. Our recent work has investigated AMD in patients with myeloproliferative neoplasms (MPNs) since they have increased drusen and AMD prevalence. We have previously found increased levels of chronic low-grade inflammation (CLI) in MPN patients with drusen (MPNd) compared to MPN patients with normal retinas (MPNn). CLI and AMD are both associated with aging, and we, therefore, wanted to study immunosenescence markers in MPNd, MPNn, and AMD. The purpose was to identify differences between MPNd and MPNn, which might reveal novel information relevant to drusen pathophysiology and thereby the AMD pathogenesis. Our results suggest that MPNd have a T cell differentiation profile resembling AMD and more effector memory T cells than MPNn. The senescence-associated-secretory-phenotype (SASP) is associated with effector T cells. SASP is thought to play a role in driving CLI seen with advancing age. Senescent cells with SASP may damage healthy tissue, including the eye tissues affected in AMD. The finding of increased effector cells in MPNd could implicate a role for adaptive immunity and senescent T cells together with increased CLI in drusen pathophysiology.

A Balanced Robertsonian Translocation in a Patient with a Janus Kinase 2-Positive Polycythemia Vera

A male patient with a persistent, combined erythrocytosis, leukocytosis, and thrombocytosis without representative evidence of reactive increase emerged as having a myeloproliferative disorder. Molecular-biological assessment yielded Janus kinase 2-positive results, and the patient was diagnosed with polycythemia vera. In addition to these findings, further karyotyping accounted for a Robertsonian translocation. Because this rearrangement was a balanced variant, we concluded that this cytogenetic result might not significantly alter the diagnosis of polycythemia vera.

Covert Brain Infarcts in Patients with Philadelphia Chromosome-Negative Myeloproliferative Disorders

Backgrounds and Purpose. Philadelphia chromosome-negative myeloproliferative disorders (Ph-negative MPD) are a rare group of hematological diseases, including three distinct pathologies: essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF). They most often manifest with thrombotic complications, including cerebrovascular events. Covert brain infarcts (CBIs) are defin ed as predominantly small ischemic cerebral lesions that are detected using magnetic resonance imaging (MRI) in the absence of clinical stroke events. The relationship between MPD and CBIs remains unclear. Methods. Included in the study were 103 patients with the diagnosis of Ph-MPD (according to WHO 2016 criteria) (median age—47 (35; 54) years; 67% female). In total, 38 patients had ET, 42 had PV, and 23 had PMF. They underwent clinical examination, routine laboratory analyses (complete blood count), brain MRI, ultrasound carotid artery, flow-mediated dilatation (as a measure of endothelial dysfunction—FMD). Results. Overall, 23 patients experienced an ischemic stroke (as per MRI and/or clinical history), of which 16 (15.5%) could be classified as CBIs. The rate of CBIs per MPD subtype was statistically non-significant between groups (p = 0.35): ET–13.2%, PV–21.4%, and PMF–8.7%. The major vascular risk factors, including arterial hypertension, carotid atherosclerosis, and prior venous thrombosis, were not associated with CBIs (p > 0.05). Age was significantly higher in patients with CBIs compared to patients without MRI ischemic lesions: 50 (43; 57) years vs. 36 (29; 48) (p = 0.002). The frequency of headaches was comparable between the two groups. CBIs were associated with endothelial dysfunction (OR - 0.71 (95% CI: 0.49–0.90; p = 0.02)) and higher hemoglobin levels (OR—1.21 (95% CI: 1.06–1.55); p =0.03). Conclusions. CBIs are common in patients with Ph-negative MPD. Arterial hypertension and carotid atherosclerosis were not associated with CBIs in this group of patients. The most significant factors in the development of CBIs were endothelial dysfunction (as measured by FMD) and high hemoglobin levels. Patients with Ph-negative MPD and CBIs were older and had more prevalent endothelial dysfunction.

Rationale and design of the multicentric, double-blind, double-placebo, randomized trial APrepitant versus HYdroxyzine in association with cytoreductive treatments for patients with myeloproliferative neoplasia suffering from Persistent Aquagenic Pruritus. Trial acronym: APHYPAP

Background

Aquagenic pruritus (AP), an intense sensation of scratching induced after water contact, is the most troublesome aspect of BCR-ABL1-negative myeloproliferative neoplasms (MPNs). Mostly described in polycythemia vera (PV, ~ 40%), it is also present in essential thrombocythemia (ET) and primary myelofibrosis (PMF) (10%). Even if this symptom can decrease or disappear under cytoreductive treatments, 30% of treated MPN patients still persist with a real impact on the quality of life (QoL). Because its pathophysiology is poorly understood, efficient symptomatic treatments of AP are missing. The neuropeptide substance P (SP) plays a crucial role in the induction of pruritus. Several studies showed the efficacy of aprepitant, an antagonist of SP receptor (NK-1R), in the treatment of chronic pruritus but never evaluated in AP. The objectives of APHYPAP are twofold: a clinical aim with the evaluation of the efficacy of two drugs in the treatment of a persistent AP for MPN patients and a biological aim to find clues to elucidate AP pathophysiology.

Methods/design

A multicentric, double-blind, double-placebo, randomized study will include 80 patients with MPN (PV or ET or PMF) treated since at least 6 months for their hemopathy but suffering from a persistent AP (VAS intensity ≥6/10). Patients will be randomized between aprepitant (80 mg daily) + placebo to match to hydroxyzine OR hydroxyzine (25 mg daily) + placebo to match to aprepitant for 14 days. At D0, baseline information will be collected and drugs dispense. Outcome measures will be assessed at D15, D30, D45, and D60. The primary study endpoint will be the reduction of pruritus intensity below (or equal) at 3/10 on VAS at D15. Secondary outcome measures will include the number of patients with a reduction or cessation of AP at D15 or D60; evaluation of QoL and AP characteristics at D0, D15, D30, D45, and D60 with MPN-SAF and AP questionnaires, respectively; modification of plasmatic concentrations of cytokines and neuropeptides at D0, D15, D30, and D60; and modification of epidermal innervation density and pruriceptor expression at D0 and D15.

Discussion

The APHYPAP trial will examine the efficacy of aprepitant vs hydroxyzine (reference treatment for AP) to treat persistent AP in MPN patients. The primary objective is to demonstrate the superiority of aprepitant vs hydroxyzine to treat persistent AP of MPN patients. The treatment received will be considered efficient if the AP intensity will be reduced at 3/10 or below on VAS after 14 days of treatment. The results of this study may provide a new treatment option for this troublesome symptom and also give us more insights in the pathophysiology understanding of AP.

Trial registration

APHYPAP. NCT03808805, first posted: January 18, 2019; last update posted: June 10, 2021. EudraCT 2018-090426-66

A Practical Approach to Polycythemia in the Outpatient Setting and Its Importance

Polycythemia left undiagnosed or untreated may result in a number of sequelae including myocardial infarction or cerebral vascular accidents. While the diagnostic criteria, classification, and workup are established, many practitioners fail to either initiate the process or perform the correct workup. Most clinicians are familiar with polycythemia and its respective clinical encounters, nevertheless, the fact that it is so frequently misdiagnosed or improperly worked up necessitates additional education. This case report covers three practical clinical examples of outpatient polycythemia, and their respective workups Furthermore, this publication will discuss the diagnostic criteria laid out by the World Health Organization and the confusion regards complications based on etiology.

Coexistence of Prefibrotic Myelofibrosis with Monoclonal Gammopathy of Undetermined Significance: A Case Report

The coexistence of dual hematological neoplasms is an unusual and challenging presentation due to the different combination of etiopathology. The presentation of synchronous dual hematological malignancies can be one of the 3 types: myeloid + lymphoid or dual lymphoid or dual myeloid. Here, we are reporting a case of a 53-year-old male with simultaneous presence of JAK2 V617F-positive myeloproliferative neoplasm with features favoring prefibrotic phase of primary myelofibrosis (pre-PMF) in combination with monoclonal gammopathy of undetermined significance (MGUS). In such cases of simultaneous existence of dual hematological neoplasm management, it is recommended to treat the more aggressive one. Currently, our management plan is focusing on treating the pre-PMF and observation of MGUS with regular monitoring for transformation to MM.

An Abnormal Host/Microbiomes Signature of Plasma-Derived Extracellular Vesicles Is Associated to Polycythemia Vera

Polycythemia Vera (PV) is a myeloproliferative neoplasm with increased risk of thrombosis and progression to myelofibrosis. Chronic inflammation is commonly observed in myeloproliferative neoplasms including PV. The inflammatory network includes the extracellular vesicles (EVs), which play a role in cell-cell communication. Recent evidence points to circulating microbial components/microbes as potential players in hemopoiesis regulation. To address the role of EVs in PV, here we investigated phenotype and microbial DNA cargo of circulating EVs through multidimensional analysis. Peripheral blood and feces were collected from PV patients (n=38) and healthy donors (n=30). Circulating megakaryocyte (MK)- and platelet (PLT)-derived EVs were analyzed by flow cytometry. After microbial DNA extraction from feces and isolated EVs, the 16S rDNA V3-V4 region was sequenced. We found that the proportion of circulating MK-derived EVs was significantly decreased in PV patients as compared with the healthy donors. By contrast, the proportion of the PLT-derived EVs was increased. Interestingly, PV was also associated with a microbial DNA signature of the isolated EVs with higher diversity and distinct microbial composition than the healthy counterparts. Of note, increased proportion of isolated lipopolysaccharide-associated EVs has been demonstrated in PV patients. Conversely, the gut microbiome profile failed to identify a distinct layout between PV patients and healthy donors. In conclusion, PV is associated with circulating EVs harbouring abnormal phenotype and dysbiosis signature with a potential role in the (inflammatory) pathogenesis of the disease.

Extramedullary Hematopoiesis of the Liver and Spleen

Hematopoiesis is the formation of blood cellular components and, consequently, immune cells. In a more complete definition, this process refers to the formation, growth, maturation, and specialization of blood cells, from the hematopoietic stem cell, through the hematopoietic progenitor cells, to the s pecialized blood cells. This process is tightly regulated by several elements of the bone marrow microenvironment, such as growth factors, transcription factors, and cytokines. During embryonic and fetal development, hematopoiesis takes place in different organs: the yolk sac, the aorta–gonad mesonephros region, the lymph nodes, and not lastly, the fetal liver and the spleen. In the current review, we describe extramedullary hematopoiesis of the spleen and liver, with an emphasis on myeloproliferative conditions.

Use of nailfold video capillaroscopy in polycythemia vera

Objectives

In this study, we aimed to investigate capillary vessel diameters and structural changes of capillaries by using nailfold video capillaroscopy (NVC) in patients with polycythemia vera (PV).

Patients and methods

This cross-sectional study included a total of 24 patients (19 males, 5 females; mean age: 59.8±12.9 years; range, 50.2 to 68 years) who were diagnosed with PV and 15 healthy controls (11 males, 4 females; mean age: 40.7±5.1 years; range, 36 to 44 years) between June 2016 and February 2017. Nailfold video capillaroscopy was performed by an experienced rheumatologist who was blinded to clinical data. The apical, arterial, and venous limb diameters of capillaries were measured and microvascular changes of capillaries were scored.

Results

When capillaries were evaluated in terms of morphological structures, giant capillary was detected in 67% of the patients with PV and 0% in the control group (p<0.05). The arterial, venous, and apical diameters of the capillaries were significantly higher in the patients with PV compared to the control group (p<0.001).

Conclusion

The presence of giant capillaries and the marked increase of arterial, venous, and apical diameters of capillaries seem to be related to PV. As it additionally plays an important role in diagnosis, prognosis, and treatment monitoring of certain diseases, capillaroscopy can be considered to be a promising microcirculation biomarker.

Philadelphia-positive acute lymphoblastic leukemia in a case of MPL p.(W515L) variant essential thrombocythemia: case report and literature review

Acute lymphoblastic leukemia (ALL) arising in preexisting myeloproliferative neoplasms (MPN) is rare with historical cases unable to differentiate between concomitant malignancies or leukemic transformation. Here, we report a case of patient with Philadelphia positive B lymphoblastic leukemia (Ph+ALL) who developed from MPL-mutated essential thrombocythemia (ET) 13 years after initial presentation. Molecular studies showed the discrepancy between the high percentage of lymphocyte blasts (91%) and the low MPL p.(W515L) variant allele frequency (2.59%) at diagnosis in the bone marrow, indicating that the Ph+ALL clone did not originate from the ET clone carrying the MPL p.(W515L) variant. After the treatment of a new tyrosine kinase inhibitor flumatinib and prednisolone, cytogenetic and molecular remission had been achieved rapidly and followed by the recovery of original ET manifestation. Although relapsed eventually, this is still a very rare case of simultaneous presence of two cytogenetics abnormalities and evolution of MPL p.(W515L) variant ET to Ph+ALL and may provide evidence to illustrate the clonal relationship of MPN and post-MPN ALL.

Essential Thrombocythemia in Children and Adolescents

Simple Summary

Among chronic Ph-negative myeloproliferative neoplasms, essential thrombocythemia is found in children with low but increasing incidence. The diagnostic and clinical features do not completely overlap with ET of adult age. A significant number of cases, in fact, do not meet the criteria of clonality, and many cases require extensive clinical evaluation to exclude secondary, reactive forms. Therefore, histological analysis of bone marrow biopsy is necessary, and its use should be enforced. The clinical course appears to be more benign, at least within the first decades of observation, with the incidence of thrombotic events being much lower than in adults (4 % vs. 30%). Hemorrhages are mostly irrelevant. Therefore, the management should be carefully adapted to the individual patient, balancing the risk of future complications with long-term collateral effects of any drug. This review analyzes the peculiarities of the disease facing similarities and differences with adult scenarios.

Abstract

This paper reviews the features of pediatric essential thrombocythemia (ET). ET is a rare disease in children, challenging pediatric and adult hematologists alike. The current WHO classification acknowledges classical Philadelphia-negative MPNs and defines diagnostic criteria, mainly encompassing adult cases. The presence of one of three driver mutations (JAK2V617F, CALR, and MPL mutations) represent the proof of clonality typical of ET. Pediatric ET cases are thus usually confronted by adult approaches. These can fit only some patients, because only 25–40% of cases present one of the driver mutations. The diagnosis of hereditary, familial thrombocytosis and the exclusion of reactive/secondary thrombocytosis must be part of the diagnostic process in children and can clarify most of the negative cases. Still, many children present a clinical, histological picture of ET, with a molecular triple wild-type status. Moreover, prognosis seems more benign, at least within the first few decades of follow-up. Thrombotic events are rare, and only minor hemorrhages are ordinarily observed. As per the management, the need to control symptoms must be balanced with the collateral effects of lifelong drug therapy. We conclude that these differences concert a compelling case for a very careful therapeutic approach and advocate for the importance of further cooperative studies.

Aberrant expression of SPAG6 may affect the disease phenotype and serve as a tumor biomarker in BCR/ABL1-negative myeloproliferative neoplasms

Sperm-associated antigen 6 (SPAG6) is a newly identified cancer-testis antigen that has been revealed to contribute to the occurrence and development of various types of human cancer, such as ovarian, bladder, breast and lung cancer. However, to the best of our knowledge, the expression levels of SPAG6 in breakpoint cluster region (BCR)/ABL1-negative myeloproliferative neoplasms (MPNs) have not been investigated previously. Using reverse transcription-quantitative PCR and different tissue staining techniques, the present study revealed that SPAG6 was expressed by MPN cells, both at the mRNA and protein levels, and that nucleated erythroid precursors and megakaryocytes expressed the highest levels of SPAG6. In addition, SPAG6, which is known as a microtubule-associated protein, was found to exhibit nucleic, cytoplasmic or both cytoplasmic and nucleic subcellular localization patterns within the same patient or cell type; however, it did not always co-localize with β-tubulin. Furthermore, SPAG6 expression was revealed to be associated with fewer splenomegaly [P=0.015 for polycythemia vera (PV) and essential thrombocythemia (ET); and P=0.012 for primary myelofibrosis (PMF)] and myelofibrosis events (P=0.014 for PV and ET; and P=0.004 for PMF). In patients with PMF, upregulated expression levels of SPAG6 were also found to be associated with lower white blood cell counts (P=0.042) and lactate dehydrogenase levels (P=0.012), and higher hemoglobin levels (P=0.031) and platelet counts (P=0.025). In addition, the receiver operating characteristic curve analysis indicated that SPAG6 may be a potential biomarker for distinguishing MPN cases from healthy individuals. In conclusion, to the best of our knowledge, the present study is the first to report that aberrant SPAG6 expression may affect the disease phenotype and serve as a tumor biomarker in BCR/ABL1-negative MPNs.

Polycythemia vera in pregnancy represents a challenge for a multidisciplinary collaboration: A case report and literature review

Polycythemia vera (PV) is a rare chronic myeloproliferative neoplasm which represents an additional thrombotic factor in pregnancy. PV may be difficult to diagnose, particularly as its incidence is extremely uncommon among young women. The main diagnostic method involves a bone marrow biopsy, and high hemoglobin and platelet counts are usually indicative of the condition, after excluding other more frequent pathologies. PV is associated with a high risk of thrombosis, particularly in pregnancy, and requires anti-platelet treatment. At present, only a limited number of PV cases in pregnancy have been reported in the literature, at least to the best of our knowledge, with the largest case series being a retrospective study that included 25 pregnancies in 15 women. The present study describes the case of a patient diagnosed with JAK2-positive PV and also discusses this rare condition with particular focus on the following: i) The management of PV in pregnancy along with the additional pathologies in this specific case; and ii) the particularities of the pregnancy course. By identifying women suffering from PV superimposed by other possible procoagulant factors and applying the latest standard in healthcare, fetal and maternal prognosis may be significantly improved.