Polycythemia vera treatment algorithm 2018

Analysis of real-world data demonstrating the efficacy of current management of polycythaemia vera in attaining and maintaining therapeutic haematocrit

BACKGROUND

Polycythaemia vera (PV) is a Philadelphia-negative myeloproliferative neoplasm, typically driven by acquired JAK2 mutation and characterised by elevated red cell mass and increased risk of thrombotic events. Patients are managed with phlebotomy to maintain haematocrit (Hct) < 0.45, and patients stratified as 'high risk' for thrombosis are additionally treated with cytoreductive agents to attain this target.

STUDY

This analysis of newly diagnosed JAK2 mutant PV patients (n = 50) over 2 years aimed to determine how effectively patients attained and maintained target Hct according to recommended practice.

CONCLUSIONS

We found that patients spent the majority of time in target Hct range. Findings are supportive of current management guidelines.

A Review About the Assessment of the Bleeding and Thrombosis Risk for Patients With Myeloproliferative Neoplasms Scheduled for Surgery

Myeloproliferative neoplasms (MPNs) present a unique challenge in surgical management due to their inherent predisposition to both bleeding and thrombosis. MPNs are a heterogenous group of acquired clonal conditions. The three classic MPNs are essential thrombocythemia (ET), myelofibrosis (PMF), and polycythemia vera (PV). All subtypes of MPN are associated with both thrombotic and bleeding complications. There are four risk categories for thrombosis in MPN patients: age, thrombosis history, and JAK-2 mutation. They are further classified as very low, low, intermediate, and high risk. The genetic landscape of MPN is fascinating and complex like all myeloid disorders. Bleeding risk can be assessed through leukocytosis, thrombocytosis, acquired von Willebrand syndrome (AVWS), and a previous history of bleeding in a patient. Risk assessment and perioperative management are important aspects of improving the quality of life and preventing complications in surgeries. Preoperative management includes a risk assessment of venous thromboembolism, use of appropriate pharmacological treatment, platelet count control, and correction and cardiovascular risk factors. This review summarizes the assessment of bleeding and thrombosis risk for patients with MPNs scheduled for surgery. Furthermore, this review discusses various tools that can be used to identify MPN patients at risk of thrombosis prior to surgery.

Hemorrhagic Coagulation Disorders and Ischemic Stroke: How to Reconcile Both?

Coagulation and fibrinolytic system disorders are conditions in which the blood's ability to clot is impaired, resulting in an increased risk of thrombosis or bleeding. Although these disorders are the expression of two opposing tendencies, they can often be associated with or be a consequence of each other, contributing to making the prognosis of acute cerebrovascular events more difficult. It is important to recognize those conditions that are characterized by dual alterations in the coagulation and fibrinolytic systems to reduce the prognostic impact of clinical conditions with difficult treatment and often unfortunate outcomes. Management of these individuals can be challenging, as clinicians must balance the need to prevent bleeding episodes with the potential risk of clot formation. Treatment decisions should be made on an individual basis, considering the specific bleeding disorder, its severity, and the patient's general medical condition. This review aims to deal with all those forms in which coagulation and fibrinolysis represent two sides of the same media in the correct management of patients with acute neurological syndrome. Precision medicine, personalized treatment, advanced anticoagulant strategies, and innovations in bleeding control represent future directions in the management of these complex pathologies in which stroke can be the evolution of two different acute events or be the first manifestation of an occult or unknown underlying pathology.

Diagnosis and Management of Cardiovascular Risk in Patients with Polycythemia Vera

Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by aberrant myeloid lineage hematopoiesis with excessive red blood cell and pro-inflammatory cytokine production. Patients with PV present with a range of thrombotic and hemorrhagic symptoms that affect quality of life and reduce overall survival expectancy. Thrombotic events, transformation into acute myeloid leukemia, and myelofibrosis are largely responsible for the observed mortality. Treatment of PV is thus primarily focused on symptom control and survival extension through the prevention of thrombosis and leukemic transformation. Patients with PV frequently experience thrombotic events and have elevated cardiovascular risk, including hypertension, dyslipidemias, obesity, and smoking, all of which negatively affect survival. To reduce the risk of thrombotic complications, PV therapy should aim to normalize hemoglobin, hematocrit, and leukocytosis and, in addition, identify and modify cardiovascular risk factors. Herein, we review what is currently known about the associated cardiovascular risk and propose strategies for diagnosing and managing patients with PV.

ST-Segment Elevation Myocardial Infarction and Bleeding Complications in JAK2-Negative Polycythemia

Thrombotic and bleeding complications are major causes of morbidity and mortality in patients with polycythemia vera, who predominantly present with an alteration in the JAK2 gene. Because of their hypercoagulable state and risk of hemorrhage, patients with polycythemia vera who present with an acute myocardial infarction pose a challenge to physicians. This case report describes the presentation and treatment of a Hispanic patient with JAK2 V617F-negative primary polycythemia who developed cardiac arrest and ST-segment elevation myocardial infarction owing to complete occlusion of the left anterior descending artery as well as bleeding complications and postmyocardial pericarditis.

Polycythemia vera disease profile in an African population-experience from a tertiary facility in Ghana

Objectives

The study describes the clinical and laboratory profile of the patients with polycythemia vera at Komfo Anokye Teaching Hospital in Kumasi, Ghana.

Methods and design

This was a retrospective hospital-based cohort study conducted from September 2020 to August 2022. Hematology clinic entry book was used to identify the patient's unique hospital code. Using these unique codes, retrospective data were collected using an Excel spreadsheet from the Hospital Lightwave health information management system (LHIMS) database.

Results

A total of 20 participants were recruited over the period of 2 years. The overall mean age was 51.53 ± 16.39 years. The hematological profile of the male participants revealed a mean hemoglobin of 18.25 ± 1.373 g/dl, mean hematocrit of 52 ± 3.47%, and a mean platelet of 345.5 ± 180.82. Comparatively, the mean hemoglobin, hematocrit, and platelet for the female participants were higher with figures of 19.26 ± 1.43 g/dl, 53 ± 3.61%, and 816 ± 935.32, respectively. Headache, tiredness, numbness, splenomegaly, and abnormal labs were the most common reasons why participants sought medical attention. Majority (60%) of the study participants had Janus Kinase 2 mutation. New-onset hypertension was identified in 45% of the study participants during follow-up. Thromboembolism was seen in 10% of the study population.

Conclusion

Polycythemia vera is an uncommon disease in Ghana mostly found in older males above 50 years. It is important to recognize it early to initiate therapy aimed at preventing common complications such as hypertension and thromboembolism. Polycythemia vera should be considered a differential diagnosis for patients with secondary hypertension.

Downregulated KLF2 in polycythemia vera and essential thrombocythemia induces prothrombotic gene expression

Thromboses are major causes of morbidity and mortality in polycythemia vera (PV) and essential thrombocythemia (ET) diseases associated with JAK2V617F mutation. However, the molecular mechanism(s) of increased thrombosis in PV and ET remain unknown. Kruppel-like factor 2 (KLF2) is a transcription factor that regulates expression of genes associated with inflammation and thrombosis; the absence of KLF2 in neutrophils causes thrombosis by inducing tissue factor. We studied the role of KLF2 in regulating prothrombotic gene expression in PV and ET. Neutrophils and platelets KLF2 expression in PV and ET was lower than the controls. Furthermore, in patients with thromboses, KLF2 transcripts were lower in platelets than those without thromboses. JAK2V617F allelic burden was inversely correlated with KLF2 transcript levels, suggesting JAK-STAT pathway may downregulate KLF2 expression. Whole transcriptome analyses of neutrophils and platelets showed that a lower KLF2 expression was associated with an upregulation of KLF2-regulated thrombotic genes. In addition, low KLF2 expression in platelets positively correlated with thrombotic events. In patients with PV and ET, KLF2 expression was induced by pegylated interferon alfa (PegINF-α) but not by hydroxyurea treatments. These data suggest that KLF2 may be a regulator of PV and ET thrombosis and a novel therapeutic target to prevent thrombosis.

Revisiting the impact of serial therapeutic phlebotomy in polycythaemia on laboratory and clinical parameters using a fixed interval and fixed volume protocol

OBJECTIVES

Therapeutic phlebotomy allows for a controlled and gradual decrease in red cell mass leading to improved blood flow and symptomatic relief in polycythaemia. The present study was aimed to determine the impact of serial fixed volume and fixed interval therapeutic phlebotomy protocol on the laboratory and clinical parameters in patients of polycythaemia.

MATERIAL AND METHODS

This prospective longitudinal study was conducted over 18 months. The desired haematocrit for polycythemia vera and secondary polycythemia was 45% and 52% respectively. A fixed volume of 350 ml phlebotomy was performed every-three days till the achievement of desired haematocrit. Complete blood count was performed before and after each procedure and iron studies were done at the time of enrolment and after the achievement of desired haematocrit. Post-procedure symptomatic relief was assessed by a 10-point visual analogue scale (VAS).

RESULTS

Of the 29 patients enrolled in the study, 3 patients were lost to follow up and data of 26 patients was analyzed. Mean Hb declined from 17.84 ± 1.88 gdL^-1 to 14.67 ± 1.14 gdL^-1 (p < 0.001) and mean haematocrit decreased from a baseline of 57.11 ± 5.47% to 46.27 ± 3.763% (p < 0.001) upon achievement of desired haematocrit. There was a significant decline in serum iron from the baseline of 132.85 ± 94.136 μg dL^-1 to 69.41 ± 58.643 μg dL^-1 at desired haematocrit. A significant change in VAS score of almost all clinical parameters was observed. Post phlebotomy hematocrit correlated negatively with the number of procedures (p = 0.015).

CONCLUSION

Our protocol yielded rapid and marked improvement in patients of primary and secondary polycythemia with minimal adverse events and significant amelioration of clinical parameters.

The international consensus classification of myeloid neoplasms and acute Leukemias: myeloproliferative neoplasms

A group of international experts, including hematopathologists, oncologists, and geneticists were recently summoned (September 2021, Chicago, IL, USA) to update the 2016/17 World Health Organization classification system for hematopoietic tumors. After careful deliberation, the group introduced the new International Consensus Classification (ICC) for Myeloid Neoplasms and Acute Leukemias. This current in-depth review focuses on the ICC-2022 category of JAK2 mutation-prevalent myeloproliferative neoplasms (MPNs): essential thrombocythemia, polycythemia vera, primary myelofibrosis, and MPN, unclassifiable. The ICC MPN subcommittee chose to preserve the primary role of bone marrow morphology in disease classification and diagnostics, while also acknowledging the complementary role of genetic markers for establishing clonality, facilitating MPN subtype designation, and disease prognostication.

S, R. D. JAK2 Mutation and Its Assessment in Relation to Profile of Young Polycythemia Patients in India

Purpose The main aim of this study was to detect the presence of JAK2 mutation and its assessment in relation to the clinical, hematological, and mutational profile of young patients with established polycythemia.

Methods Cross-sectional observational study was undertaken over a period of 1 year in a tertiary care center. Sixty patients were included in our study between the age 18 and 50 years with confirmed diagnosis of polycythemia vera. Reports of all the investigations including bone marrow biopsy and JAK2 mutation testing were assessed.

Results Presence of JAK2 mutation V617F was found in 38% patients, while bone marrow panmyelosis was present in 67% patients. Higher mean hemoglobin levels were observed in JAK2 mutation-positive patients, compared with those who were negative. Thrombosis-related complications were observed in five patients, all of whom were JAK2 mutation positive, while out of the 18 patients requiring phlebotomy, 15 patients were JAK2 mutation positive.

Conclusion JAK2 mutation V617F in young Indian population is seen in significantly less cases as compared with Western data, while bone marrow panmyelosis is frequently observed and thus a significant finding for diagnosing polycythemia in our setting. Median hemoglobin was greater for JAK2 mutation-positive cases and so were the phlebotomy requirements and thrombotic events occurrences. Forty-two percent patients had history of some exposure to high-altitude areas adhering to the fact that high altitude is an established risk factor for developing polycythemia and the same is reinforced by our study.

Hospital incidence and medical costs of polycythemia vera in Spain: a retrospective database analysis

BACKGROUND

Polycythemia vera (PV) is one of the most common chronic myeloproliferative neoplasms, yet, little data is available on the epidemiology of PV in Spain and the costs of its management. This study aimed to evaluate the hospital incidence and mortality rate of PV in Spain, and to estimate hospital medical costs.

METHODS

Hospital admission records of patients with PV registered between 2005 and 2019 were obtained from a Spanish hospital discharge database and analyzed in a retrospective multicenter study.

RESULTS

Admission files of 490 patients were reviewed. Median age was 74 years; patients presented numerous conditions associated to age, namely hypertension, diabetes or anemia. Hospital mortality rate was associated to pulmonary heart disease, respiratory conditions and kidney disease. Most of the files analyzed corresponded to inpatient admissions; hospital incidence decreased over the study period in patients over 60 years. Median admission cost was €5580, increasing in patients deceased during the hospitalization. Admission cost increased significantly between 2006 and 2011.

CONCLUSIONS

This study provides an evaluation of hospital management and costs of PV in Spain. Future studies should focus on the revision of disease management in the country and measuring total medical costs, which could be higher than global estimations.

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.

Polycythemia vera: historical oversights, diagnostic details, and therapeutic views

Polycythemia vera (PV) is a relatively indolent myeloid neoplasm with median survival that exceeds 35 years in young patients, but its natural history might be interrupted by thrombotic, fibrotic, or leukemic events, with respective 20-year rates of 26%, 16%, and 4%. Current treatment strategies in PV have not been shown to prolong survival or lessen the risk of leukemic or fibrotic progression and instead are directed at preventing thrombotic complications. In the latter regard, two risk categories are considered: high (age >60 years or thrombosis history) and low (absence of both risk factors). All patients require phlebotomy to keep hematocrit below 45% and once-daily low-dose aspirin, in the absence of contraindications. Cytoreductive therapy is recommended for high-risk or symptomatic low-risk disease; our first-line drug of choice in this regard is hydroxyurea but we consider pegylated interferon as an alternative in certain situations, including in young women of reproductive age, in patients manifesting intolerance or resistance to hydroxyurea therapy, and in situations where treatment is indicated for curbing phlebotomy requirement rather than preventing thrombosis. Additional treatment options include busulfan and ruxolitinib; the former is preferred in older patients and the latter in the presence of symptoms reminiscent of post-PV myelofibrosis or protracted pruritus. Our drug choices reflect our appreciation for long-term track record of safety, evidence for reduction of thrombosis risk, and broader suppression of myeloproliferation. Controlled studies are needed to clarify the added value of twice- vs once-daily aspirin dosing and direct oral anticoagulants. In this invited review, we discuss our current approach to diagnosis, prognostication, and treatment of PV in general, as well as during specific situations, including pregnancy and splanchnic vein thrombosis.

MTAP-related increased erythroblast proliferation as a mechanism of polycythaemia vera

Polycythaemia vera (PV) is a haematological disorder caused by an overproduction of erythroid cells. To date, the molecular mechanisms involved in the disease pathogenesis are still ambiguous. This study aims to identify aberrantly expressed proteins in erythroblasts of PV patients by utilizing mass spectrometry-based proteomic analysis. Haematopoietic stem cells (HSCs) were isolated from newly-diagnosed PV patients, PV patients who have received cytoreductive therapy, and healthy subjects. In vitro erythroblast expansion confirmed that the isolated HSCs recapitulated the disease phenotype as the number of erythroblasts from newly-diagnosed PV patients was significantly higher than those from the other groups. Proteomic comparison revealed 17 proteins that were differentially expressed in the erythroblasts from the newly-diagnosed PV patients compared to those from healthy subjects, but which were restored to normal levels in the patients who had received cytoreductive therapy. One of these proteins was S-methyl-5′-thioadenosine phosphorylase (MTAP), which had reduced expression in PV patients’ erythroblasts. Furthermore, MTAP knockdown in normal erythroblasts was shown to enhance their proliferative capacity. Together, this study identifies differentially expressed proteins in erythroblasts of healthy subjects and those of PV patients, indicating that an alteration of protein expression in erythroblasts may be crucial to the pathology of PV.

Ruxolitinib (a JAK2 inhibitor) as an emerging therapy for refractory pruritis in a patient with low-risk polycythemia vera: A case report

INTRODUCTION

Polycythemia vera (PV) is a Philadelphia-negative myeloproliferative neoplasm (MPN) characterized by the overproduction of red blood cells. The presence of JAK2 mutation is detected in up to 99% of patients with PV. Pruritis is commonly encountered in patients with PV and is considered the most troublesome symptom. Multiple treatment modalities are used for treatment; however, their efficacy is variable. Sometimes, pruritis will not improve even by the use of combined therapies. Recently, Ruxolitinib (a JAK2 inhibitor) has been shown to be very effective, especially in patients with refractory pruritis in the setting of other treatment modalities failure.

PATIENT CONCERN

We describe a 55-year-old male with history of low risk PV presented with severe itching despite using different therapies, including phlebotomy and hydroxyurea. His laboratory results on presentation were significant for red blood cells (RBC) of 8.2 × 106/uL (normal = 4.5-5.5), hematocrit (Hct) of 52.8% (normal = 40-50%), platelet count of 519 × 103/uL (normal = 150-400), white blood cells count of 12.3 × 103/uL (normal = 4-10), and basophils count of 0.22 × 103/uL (normal < 0.1).

DIAGNOSIS

PV related refractory pruritis.

INTERVENTION

Pruritis improved dramatically after starting Ruxolitinib therapy with an improvement of hematological parameters (both hematocrit and platelet count).

CONCLUSION

Different treatment modalities have shown to be beneficial in treating PV-related pruritis, but the clinical outcomes are highly variable. This case report aims to shed light on Ruxolitinib as an emerging therapy for the treatment of refractory cases of PV-related pruritis.

NK Cells in Myeloproliferative Neoplasms (MPN)

Simple Summary

NK cells are important innate immune effectors that contribute substantially to tumor control, however the role of NK cells in haematological cancers is not as well understood. The aim of this review is to highlight the importance of the role of NK cells in the management of Ph+ Myeloproliferative Neoplasms, and emphasize the need and possible benefits of a more in-depth investigation into their role in classical MPNs and show potential strategies to harness the anti-tumoral capacities of NK cells.

Abstract

Myeloproliferative neoplasms (MPNs) comprise a heterogenous group of hematologic neoplasms which are divided into Philadelphia positive (Ph+), and Philadelphia negative (Ph−) or classical MPNs. A variety of immunological factors including inflammatory, as well as immunomodulatory processes, closely interact with the disease phenotypes in MPNs. NK cells are important innate immune effectors and substantially contribute to tumor control. Changes to the absolute and proportionate numbers of NK cell, as well as phenotypical and functional alterations are seen in MPNs. In addition to the disease itself, a variety of therapeutic options in MPNs may modify NK cell characteristics. Reports of suppressive effects of MPN treatment strategies on NK cell activity have led to intensive investigations into the respective compounds, to elucidate the possible negative effects of MPN therapy on control of the leukemic clones. We hereby review the available literature on NK cells in Ph+ and Ph− MPNs and summarize today’s knowledge on disease-related alterations in this cell compartment with particular focus on known therapy-associated changes. Furthermore, we critically evaluate conflicting data with possible implications for future projects. We also aim to highlight the relevance of full NK cell functionality for disease control in MPNs and the importance of considering specific changes related to therapy in order to avoid suppressive effects on immune surveillance.

Polycythemia vera as a rare cause of hypertension in a young man

Polycythemia vera (PV) is an orphan haematological disease and one of the most common myeloproliferative diseases, with the incidence rate of about 0.4-2.8 cases per 100 000 population per year. In patients, proliferation of all three haematopoietic lineages is observed, typically with the development of erythrocytosis. As a rule, PV occurs in patients aged 60-70 years, slightly more often in men. The main clinical signs of PV are weakness, significant burning sensation in fingers and palms due to the increased blood viscosity and microcirculation disorders, discomfort in the left hypochondrium due to splenomegaly at the background of extramedullary haematopoietic sites development, as well as gross vascular complications (thrombosis) of various localisation. Our clinical case represents a rare cardiac manifestation of the PV in a young man.

Pharmacokinetics and Pharmacodynamics of Ropeginterferon Alfa-2b in Healthy Japanese and Caucasian Subjects After Single Subcutaneous Administration

BACKGROUND AND OBJECTIVES

Ropeginterferon alfa-2b is a novel monopegylated recombinant interferon alfa-2b for the treatment of patients with polycythemia vera. The objectives of this study were to evaluate the pharmacokinetics, pharmacodynamics, safety, and tolerability of ropeginterferon alfa-2b in healthy Japanese subjects compared with Caucasian subjects.

METHODS

In this multicenter, parallel-group phase I study, a cohort consisting of six Japanese and six Caucasian subjects was designated to receive a single subcutaneous dose of ropeginterferon alfa-2b (100, 200, 300, and 450 µg). Pharmacokinetic and pharmacodynamic parameters, and immunogenicity were evaluated. Safety was assessed throughout the study.

RESULTS

Cohort 4 (450-µg dose) was not initiated because the primary objective of this study was achieved based on the three completed cohorts. A total of 36 enrolled subjects (18 Japanese and 18 Caucasian) in three cohorts were included in the safety, pharmacokinetic, and pharmacodynamic analysis sets. Ropeginterferon alfa-2b exposure in terms of the area under the serum concentration-time curve (AUC) from time zero extrapolated to infinity and the AUC from time zero to the time of the last quantifiable concentration was approximately 1.7-fold and two-fold higher in Japanese subjects than in Caucasian subjects, respectively. Across the same dose range, the maximum serum concentration was approximately 1.25-fold higher in Japanese subjects than in Caucasian subjects. The time to reach the median maximum serum concentration was similar between ethnicities (approximately 96-111 h). The terminal half-life was 48-57 h in Japanese subjects and 31-75 h in Caucasian subjects. The slope of the relationship between dose and drug exposure was greater than 1 in both ethnicities. The dose-dependent induction of beta-2 microglobulin and neopterin expression was observed in both ethnicities, and the two groups showed similar pharmacodynamic parameters. At the end of the study, 22.2% of Japanese subjects and 11.1% of Caucasian subjects developed anti-ropeginterferon alfa-2b-binding antibodies. The neutralizing capacity of these antibodies was not tested. Ropeginterferon alfa-2b up to 300 µg was safe and well tolerated, with no unexpected safety findings based on previous experiences with ropeginterferon alfa-2b and other forms of interferon.

CONCLUSIONS

Ropeginterferon alfa-2b exposure was higher in Japanese subjects than in Caucasian subjects. The increase in ropeginterferon alfa-2b exposure was greater than the dose proportion in the dose range of 100-300 µg. Ropeginterferon alfa-2b was safe and well tolerated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT03546465, registered on 6 June, 2018.

Cerebrovascular manifestations in hematological diseases: an update

Patients with hematological diseases often experience cerebrovascular complications including ischemic stroke, intracerebral and subarachnoid hemorrhage, microbleeds, posterior reversible encephalopathy syndrome, and dural sinus and cerebral vein thrombosis (CVT). In this update, we will review recent advances in the management of cerebrovascular diseases in the context of myeloproliferative neoplasms, leukemias, lymphomas, multiple myeloma, POEMS, paroxysmal nocturnal hemoglobinuria (PNH), thrombotic thrombocytopenic purpura (TTP), and sickle-cell disease. In acute ischemic stroke associated with hematological diseases, thrombectomy can in general be applied if there is a large vessel occlusion. Intravenous thrombolysis can be used in myeloproliferative neoplasms and sickle-cell anemia, but in other diseases, a case-by-case evaluation of the bleeding risks is mandatory. Patients with sickle-cell disease and acute stroke need very often to be transfused. In PNH, acute ischemic stroke patients must be anticoagulated. Most patients with CVT can be treated with low-molecular weight heparin (LMWH) acutely, even those with leukemias. Prevention of recurrence of cerebral thrombotic events depends on the control of the underlying disease, combined in some conditions with antithrombotic drugs. The recent introduction of specific monoclonal antibodies in the treatment of PHN and TTP has dramatically reduced the risk of arterial and venous thrombosis.

Risk factors and incidence of thrombosis in a Brazilian cohort of patients with Philadelphia-negative myeloproliferative neoplasms

Few data are available regarding epidemiology and outcomes of Philadelphia-negative chronic myeloproliferative neoplasms (MPN) in Latin America. Therefore, current models for MPN treatment are based in large cohorts of patients from Europe and North America. In this paper, we conducted a retrospective study to evaluate thrombotic and bleeding events in a cohort of patients with MPN from a reference center in Brazil. A total of 334 patients were included, being essential thrombocythemia the most common diagnosis. Here, we found that 41% of the MPN patients had a thrombotic event prior to the diagnosis. Thrombosis was more frequent in patients under 60 years-old. In a multivariable model, only JAK2 V617F mutation (OR 2.57 95% CI 1.58-4.18, p < 0.001) and presence of two cardiovascular risk factors (OR 1.90 95% CI 1.21-2.98, p < 0.005) were significant for thrombosis. The risk of thrombosis was similar among all subtypes of MPN. Cumulative incidence of thromboembolic event at 5 years from diagnosis was 5.8% (95% CI 3.5-8.9), which is similar to previous studies. The high incidence of thromboembolic events in younger patients suggests that socioeconomic disparities might have a role in the outcomes of MPN.

Prevention of recurrent thromboembolism in myeloproliferative neoplasms: review of literature and focus on direct oral anticoagulants

Myeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (MF) are stem cell clonal neoplasms characterized by expansion of late myeloid cells. Thrombosis risk is elevated in MPNs and contributes significantly to morbidity and mortality. Current consensus guidelines make no specific recommendations regarding anticoagulant choice for the treatment of venous thromboembolism (VTE) in MPNs, with most evidence supporting the use of vitamin K antagonists (VKAs) for secondary prophylaxis. However, direct oral anticoagulants (DOACs) are now increasingly being used, although with limited data on safety and efficacy in MPNs specifically. The widespread adoption of DOACs is based on new, high-quality evidence demonstrating safety and efficacy of DOAC treatment for cancer-associated VTE. However, these studies include few if any MPN patients, and MPNs have disease-specific considerations that may elevate thrombosis and bleeding risk. The purpose of this review is to discuss evidence behind current treatment recommendations for thrombosis in MPNs, with special attention to the use of DOACs.

Biology and Current Treatment of Myeloproliferative Neoplasms

The classical myeloproliferative neoplasms (MPN) are characterized by clonal expansion of one or more hematopoietic cell lineages and are driven by mutations that activate constitutive signaling via JAK2 pathway. The criteria for diagnosis have now been defined by the World Health Organization (WHO) and the term MPN as is currently used encompasses the entities of primary myelofibrosis, polycythemia vera, and essential thrombocytosis. There is imperfect correlation between the genotype and disease phenotype in MPN and the latter is determined by a variety of patient factors that are independent of the driver mutation. The disease course in MPN can span decades and accurate risk assessment is critical in the choice of therapy and treatment is largely geared toward prevention of complications and providing symptomatic relief. Although new agents have been approved in recent years, no therapy has been convincingly shown to alter disease progression and allogeneic hematopoietic stem cell transplantation (HCT) remains the only curative therapy known to date.

The management of hematologic malignancies during the COVID-19 pandemic

Introduction: Patients with hematological malignancies have experienced a more severe clinical course of COVID-19 and higher mortality than those with solid tumors and those without cancer. The ongoing pandemic poses many challenges in assuring the correct and timely diagnosis of hemato-oncology patients as well as the optimal treatment.Areas covered: The present paper reviews current data on the incidence and clinical course of COVID-19 in patients with hematological malignancies. A literature review of the MEDLINE database for articles was conducted via PubMed. Publications from December 2019 through September 2020 were scrutinized. The search terms used were SARS-Cov-2 OR COVID-19 in conjunction with hematological malignancies OR leukemia OR lymphoma OR multiple myeloma OR cancer. Recommendations and expert opinions either published or presented on ASH, ASCO, ESMO, NCCN websites were also reviewed.Expert opinion: The COVID-19 pandemic has brought a pressing need to improve the management of patients with hematological malignancies, including establishing prompt diagnoses and providing effective treatment while also minimalizing the risk of SARS-Cov2 infection. The recommendations developed by many organizations based on expert opinions are helpful in making proper decisions. All cancer patients should be advised to get vaccinated against influenza and pneumococcus.

Macroscopic Hematuria as the Initial Presentation of Polycythemia Vera

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm (CMN) characterized by the accumulation of red blood cells, granulocytes and platelets in the peripheral blood. The main complications of PV are an increased risk of thrombosis, bleeding and transformation to myelodysplasia or acute leukemia. The authors report the case of a 28-year-old man with a complaint of macroscopic hematuria, low back pain and edema of the left arm associated with elevated hemoglobin, hematocrit and lactic dehydrogenase, leukocytosis and increased renal volume. Computed tomography of the chest and abdomen with contrast showed venous ectasia in the left upper limb and thrombosis of the right renal vein with extension to the inferior vena cava. A diagnosis of PV was confirmed by the presence of the JAK2 mutation and a bone marrow biopsy that showed panmyelosis. The patient was anticoagulated and treatment for PV was started with aspirin, phlebotomy and hydroxyurea. Then, the patient was discharged for outpatient follow-up with a hematologist. The case emphasizes the importance of clinical suspicion for atypical presentation of the disease in an unusual age range and of adequate etiological investigation of thrombosis in unusual sites.

Patterns of Hydroxyurea Prescription and Use in Routine Clinical Management of Polycythemia Vera: A Multicenter Chart Review Study

Objective:

This study aimed to evaluate real-life data on patterns of hydroxyurea prescription/use in polycythemia vera (PV).

Materials and Methods:

This retrospective chart review study included PV patients who had received hydroxyurea therapy for at least 2 months after PV diagnosis. Data were collected from 10 representative academic medical centers.

Results:

Of 657 patients, 50.9% were in the high-risk group (age ≥60 years and/or history of thromboembolic event). The median duration of hydroxyurea therapy was 43.40 months for all patients; 70.2% of the patients had ongoing hydroxyurea therapy at last follow-up. Hydroxyurea was discontinued in 22.4% of the patients; the most common reason was death (38.5%). The predicted time until hydroxyurea discontinuation was 187.8 months (standard error: ±21.7) for all patients. This duration was shorter in females (140.3±37.7 vs. 187.8±29.7) (p=0.08). This trend was also observed in surviving patients aged ≥50 years at hydroxyurea initiation (122.2±12.4 vs. 187.8±30.7, p=0.03). Among the patients who were still on hydroxyurea therapy, 40.3% had a hematocrit concentration of ≥45% at their last follow-up visit, and the rate of patients with at least one elevated blood cell count was 67.8%.

Conclusion:

Hydroxyurea prescription patterns and treatment aims are frequently not in accordance with the guideline recommendations. Its discontinuation rate is higher in females.

Clinical, Hematologic, Biologic and Molecular Characteristics of Patients with Myeloproliferative Neoplasms and a Chronic Myelomonocytic Leukemia-Like Phenotype

Patients with a myeloproliferative neoplasm (MPN) sometimes show a chronic myelomonocytic leukemia (CMML)-like phenotype but, according to the 2016 WHO classification, a documented history of an MPN excludes the diagnosis of CMML. Forty-one patients with an MPN (35 polycythemia vera (PV), 5 primary myelofibrosis, 1 essential thrombocythemia) and a CMML-like phenotype (MPN/CMML) were comprehensively characterized regarding clinical, hematologic, biologic and molecular features. The white blood cell counts in MPN/CMML patients were not different from CMML patients and PV patients. The hemoglobin values and platelet counts of these patients were higher than in CMML but lower than in PV, respectively. MPN/CMML patients showed myelomonocytic skewing, a typical in vitro feature of CMML but not of PV. The mutational landscape of MPN/CMML was not different from JAK2-mutated CMML. In two MPN/CMML patients, development of a CMML-like phenotype was associated with a decrease in the JAK2 V617F allelic burden. Finally, the prognosis of MPN/CMML (median overall survival (OS) 27 months) was more similar to CMML (JAK2-mutated, 28 months; JAK2-nonmutated 29 months) than to PV (186 months). In conclusion, we show that patients with MPN and a CMML-like phenotype share more characteristics with CMML than with PV, which may be relevant for their classification and clinical management.

Clinical features of children with polycythemia vera, essential thrombocythemia, and primary myelofibrosis in Japan: A retrospective nationwide survey

Background

Philadelphia-negative (Ph-negative) myeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are exceptionally rare during childhood. Thus, clinical features of pediatric Ph-negative MPNs remain largely unknown. This study was therefore performed to address this.

Methods

We performed a retrospective study to collect clinical information of children diagnosed with Ph-negative MPNs from 2000 to 2016 using questionnaires in qualified institutions in Japan. The results obtained from the questionnaire survey were then combined with those from the national registry data.

Results

Among 50 children identified, five had PV, 44 had ET, and one had PMF. Median age at diagnosis was 14.0, 9.0, and 0 years, respectively. Male to female ratio was 4:1, 21:23, and 1:0, respectively. Detection rates of the JAK2 V617F variant were 0/5 in PV and 9/39 in ET. Frequencies of complications, such as thrombosis and subsequent leukemia, were lower than complication frequencies in adults. We identified two children who developed subsequent leukemia, which has not been reported previously, and one of them died.

Conclusion

This is the first nationally representative survey of pediatric Ph-negative MPNs. Given its rarity, an international collaboration with comprehensive genetic analyses might be needed to fully elucidate the clinical and genetic features.

Polycythemia vera: the current status of preclinical models and therapeutic targets

INTRODUCTION

Polycythemia vera (PV) is the most common myeloproliferative neoplasm (MPN). PV is characterized by erythrocytosis, leukocytosis, thrombocytosis, increased hematocrit, and hemoglobin in the peripheral blood. Splenomegaly and myelofibrosis often occur in PV patients. Almost all PV patients harbor a mutation in the JAK2 gene, mainly represented by the JAK2^V617F point mutation.

AREAS COVERED

This article examines the recent in vitro and in vivo available models of PV and moreover, it offers insights on emerging biomarkers and therapeutic targets. The evidence from mouse models, resembling a PV-like phenotype generated by different technical approaches, is discussed. The authors searched PubMed, books, and clinicaltrials.gov for original and review articles and drugs development status including the terms Myeloproliferative Neoplasms, Polycythemia Vera, erythrocytosis, hematocrit, splenomegaly, bone marrow fibrosis, JAK2^V617F, Hematopoietic Stem Cells, MPN cytoreductive therapy, JAK2 inhibitor, histone deacetylase inhibitor, PV-like phenotype, JAK2^V617F BMT, transgenic JAK2^V617F mouse, JAK2 physiologic promoter.

EXPERT OPINION

Preclinical models of PV are valuable tools for enabling an understanding of the pathophysiology and the molecular mechanisms of the disease. These models provide new biological insights on the contribution of concomitant mutations and the efficacy of novel drugs in a 'more faithful' setting. This may facilitate an enhanced understanding of pathogenetic mechanisms and targeted therapy.

Optimized and Personalized Phlebotomy Schedules for Patients Suffering From Polycythemia Vera

Polycythemia vera (PV) is a slow-growing type of blood cancer, where the production of red blood cells (RBCs) increase considerably. The principal treatment for targeting the symptoms of PV is bloodletting (phlebotomy) at regular intervals based on data derived from blood counts and physician assessments based on experience. Model-based decision support can help to identify optimal and individualized phlebotomy schedules to improve the treatment success and reduce the number of phlebotomies and thus negative side effects of the therapy. We present an extension of a simple compartment model of the production of RBCs in adults to capture patients suffering from PV. We analyze the model's properties to show the plausibility of its assumptions. We complement this with numerical results using exemplary PV patient data. The model is then used to simulate the dynamics of the disease and to compute optimal treatment plans. We discuss heuristics and solution approaches for different settings, which include constraints arising in real-world applications, where the scheduling of phlebotomies depends on appointments between patients and treating physicians. We expect that this research can support personalized clinical decisions in cases of PV.

Measurement of Thromboxane Biosynthesis in Health and Disease

Thromboxane (TX) A₂ is a chemically unstable lipid mediator involved in several pathophysiologic processes, including primary hemostasis, atherothrombosis, inflammation, and cancer. In human platelets, TXA₂ is the major arachidonic acid derivative via the cyclooxygenase (COX)-1 pathway. Assessment of platelet TXA₂ biosynthesis can be performed ex vivo through measurement of serum TXB₂, an index of platelet COX-1 activity, as well as in vivo through measurement of urinary enzymatic metabolites, a non-invasive index of platelet activation. This article reviews the main findings of four decades of clinical investigation based on these analytical approaches, focusing on the measurement of TXA₂ metabolites to characterize the pathophysiologic role of transiently or persistently enhanced platelet activation and to describe the clinical pharmacology of COX-1 inhibition in health and disease.

Outcomes Following Posterior Lumbar Fusion in Patients with Polycythemia Vera

BACKGROUND

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm that is associated with increased risk for venous and arterial thromboembolism. The aim of this study was to evaluate outcomes following elective posterior lumbar fusion (PLF) and/or posterior interbody fusion (PLIF) among patients with PV.

METHODS

Using PearlDiver retrospective national database, Medicare patients <85 years old who underwent elective primary PLF (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 81.07) and/or PLIF (ICD-9-CM code 81.08) for degenerative lumbar spine pathologies during 2006-2013 were identified. Patients included in the PLF and/or PLIF cohort were separated into patients with a prior diagnosis of PV (ICD-9-CM code 238.4) and a control cohort of patients without PV. Comparisons of postoperative outcomes were made between the PV patient group and matched control group. Significance was set at 0.05.

RESULTS

Selected study participants included 1491 patients with PV and 29,056 patients in the matched control group. Patients with PV had a significantly increased rate of 90-day acute pulmonary embolism (1.9% vs. 1.2%, odds ratio [OR] 1.65, 95% confidence interval [CI] 1.10-2.38, P = 0.010), 90-day lower extremity deep vein thrombosis (3.4% vs. 1.9%, OR 1.81, 95% CI 1.33-2.40, P < 0.001), and 1-year diagnosis of surgical site infection (5.4% vs. 4.2%, OR 1.30, 95% CI 1.02-1.63, P = 0.027) compared with patients without PV. Nonetheless, PV was not associated with other major medical complications, including stroke, myocardial infarction, and mortality, following PLF and/or PLIF.

CONCLUSIONS

Patients with PV undergoing elective PLF and/or PLIF have a significantly increased risk for pulmonary embolism, lower extremity deep vein thrombosis, and surgical site infection.

[Pathogenesis of thrombosis in JAK2V617F myeloproliferative neoplasms]

BCR-ABL negative myeloproliferative neoplasms are acquired hematologic diseases characterized by blood cell proliferation and that include polycythemia vera (PV), essential thrombocytemia (ET) and primary myelofibrosis (PMF). Occurring of venous and arterial thrombosis is the main complication of these diseases. Risk factors for thrombosis are individuals older than 60 and history of thrombosis. The mechanisms leading to thrombosis are complex and involve several blood compartments, plasmatic factors and endothelial cells. Over the last years, new actors of thrombosis have been discovered.

[Erythromelalgia: skin redness and pain]

Erythromelalgia is a rare disease that is associated with hemato-oncological diseases or after taking certain drugs and toxins, but it can also occur as an independent clinical picture, for example, due to mutations in the sodium channel Na_V1.7. Clinically, there is a characteristic triad of attack-like burning pain and skin redness in the area of the distal extremities, which can be alleviated by excessive cooling. The attacks are triggered by heat, exertion, and stress. The diagnosis is primarily made clinically and can be confirmed by genetic testing if a sodium channel Na_V1.7 mutation is present. Important differential diagnoses are complex regional pain syndrome, the non-freezing cold injury, and small fiber neuropathies. Therapy is multidisciplinary and has to be planned individually and include physical therapy and psychotherapy as well as drug therapy as integral components.

Addressing and proposing solutions for unmet clinical needs in the management of myeloproliferative neoplasm-associated thrombosis: A consensus-based position paper

This article presents the results of a group discussion among an ad hoc constituted Panel of experts aimed at highlighting unmet clinical needs (UCNs) in the management of thrombotic risk and thrombotic events associated with Philadelphia-negative myeloproliferative neoplasms (Ph-neg MPNs). With the Delphi technique, the challenges in Ph-neg MPN-associated thrombosis were selected. The most clinically relevant UCNs resulted in: (1) providing evidence of the benefits and risks of direct oral anticoagulants, (2) providing evidence of the benefits and risks of cytoreduction in patients with splanchnic vein thrombosis without hypercythemia, (3) improving knowledge of the role of the mutated endothelium in the pathogenesis of thrombosis, (4) improving aspirin dosing regimens in essential thrombocythemia, (5) improving antithrombotic management of Ph-neg MPN-associated pregnancy, (6) providing evidence for the optimal duration of anticoagulation for prophylaxis of recurrent VTE, (7) improving knowledge of the association between somatic gene mutations and risk factors for thrombosis, and (8) improving the grading system of thrombosis risk in polycythemia vera. For each of these issues, proposals for advancement in research and clinical practice were addressed. Hopefully, this comprehensive overview will serve to inform the design and implementation of new studies in the field.

How I treat polycythemia vera

Since its discovery, polycythemia vera (PV) has challenged clinicians responsible for its diagnosis and management and scientists investigating its pathogenesis. As a clonal hematopoietic stem cell (HSC) disorder, PV is a neoplasm but its driver mutations result in overproduction of morphologically and functionally normal blood cells. PV arises in an HSC but it can present initially as isolated erythrocytosis, leukocytosis, thrombocytosis, or any combination of these together with splenomegaly or myelofibrosis, and it can take years for a true panmyelopathy to appear. PV shares the same JAK2 mutation as essential thrombocytosis and primary myelofibrosis, but erythrocytosis only occurs in PV. However, unlike secondary causes of erythrocytosis, in PV, the plasma volume is frequently expanded, masking the erythrocytosis and making diagnosis difficult if this essential fact is ignored. PV is not a monolithic disorder: female patients deregulate fewer genes and clinically behave differently than their male counterparts, while some PV patients are genetically predisposed to an aggressive clinical course. Nevertheless, based on what we have learned over the past century, most PV patients can lead long and productive lives. In this review, using clinical examples, I describe how I diagnose and manage PV in an evidence-based manner without relying on chemotherapy.

Interferon Alpha Has a Strong Anti-tumor Effect in Philadelphia-negative Myeloproliferative Neoplasms

BACKGROUND

Despite the important progress in the research of myeloproliferative neoplasms (MPN), treatment options are still limited. Currently, a cytoreductive approach is the backbone treatment, with hydroxyurea (HU) being the most important agent. However, this drug is not always well-tolerated and has been questionably linked to a potential leukemogenic effect. A valid alternative is interferon alfa (IFN-α), but it is reserved for selected patients owing to the more frequent side effects and the lack of final results from the studies directly comparing IFN-α with HU, which is why we provided the results of the so far largest real-life analysis.

PATIENTS AND METHODS

From 2000 to 2016, 63 patients with Philadelphia-negative MPN prospectively received either HU or IFN-α.

RESULTS

During a median follow-up period of 121 months (range, 88-168 months), 97% of the patients treated with IFN-α achieved a hematologic response (60% complete, 37% partial) compared with 78% in the HU group (56% complete, 20% partial; P < .01). Molecular responses were limited to patients treated with IFN-α. IFN-α was well-tolerated with no secondary malignancy, whereas HU was associated with more toxic events and cases of leukemic transformation. A significantly longer progression-free survival (5.0 vs. 3.1 years; P < .001) and overall survival (7.8 vs. 5.8 years; P = .006) were observed in the IFN-α group compared with the HU cohort.

CONCLUSION

Our data support IFN-α as a more valid therapeutic option owing to its more profound hematologic responses, durable molecular remissions, long-term disease control, and reduced risk of leukemic transformation with a favorable toxicity profile.

Polycythemia Vera Presenting as Cardiac Arrest: Novel Management Strategies

Acute coronary syndromes (ACS) usually occur in patients with multiple cardiac risk factors. In young adults, drug use and hypercoagulable states are common causes for ACS presentations. We report a case of a man in his early 30s who was diagnosed with polycythemia vera (PV) and had a cardiac arrest due to an anterolateral ST elevation myocardial infarction. We discuss his unique management and review the evidence on the management of arterial thromboembolism in PV patients.

Characteristics and outcomes of patients with essential thrombocythemia or polycythemia vera diagnosed before 20 years of age: a systematic review

Although it is well known that myeloproliferative neoplasms occur in younger patients, few large cohorts of such patients have been reported. Thus, our knowledge about circumstances of diagnosis, outcome and treatment is limited, especially for children and young adults. We therefore performed a systematic review of cases, published since 2005, concerning patients aged below 20 years at the time of diagnosis of essential thrombocythemia or polycythemia vera. We identified 396 cases of essential thrombocythemia and 75 of polycythemia vera. The median age at diagnosis was 9.3 and 12 years, respectively, and females constituted 57.6% and 45% of the groups, respectively. Half of the patients were asymptomatic at diagnosis. The proportion of so-called triple negativity was high: 57% in essential thrombocythemia and 73% in polycythemia vera. The incidence of thrombosis during the follow-up was 9.3% in patients with polycythemia vera and less, 3.8%, in those with essential thrombocythemia. Venous events were predominant (84.2%), with hemorrhagic episodes being rarer (<5%). The risk of evolution also seemed low (2% to myelofibrosis and no reports of acute leukemia), but the median follow-up was only 50 months. Survival curves were not available. Half of the patients received an antithrombotic drug and 40.5% received a cytoreductive drug. All data should be analyzed with care because of the proportion of missing data (10.7% to 74.7%). This review highlights interesting points concerning this population of young patients with myeloproliferative neoplasms, including that such patients were identified as negative for all common driver mutations, but also shows the need for larger contemporary cohorts with longer follow-up to assess the true prognosis of these patients.

Ropeginterferon alpha-2b targets JAK2V617F-positive polycythemia vera cells in vitro and in vivo

Polycythemia vera is characterized by the acquisition of the JAK2V617F mutation. Recommended treatments include hydroxyurea and interferon-alpha. Several groups have reported a reduction in the JAK2 mutant allele burden in interferon-treated patients, but significance of this observation is questioned. We characterized the activity of ropeginterferon alpha-2b, a novel form of interferon-alpha recently shown to be safe and efficacious in polycythemia vera. Ropeginterferon was able to inhibit the proliferation of the HEL, UKE-1, and UT-7 JAK2-mutant cell lines while sparing JAK2-wild-type UT-7 and normal CD34+ cells growth. In vitro treatment of erythroid progenitors derived from PV patients showed that ropeginterferon could considerably inhibit the growth of endogenous erythroid colonies, a hallmark of polycythemia vera. Finally, we could study in sequential samples the clonal architecture of erythroid progenitors derived from patients included in a randomized study comparing hydroxyurea to ropeginterferon. After 1 year of treatment with ropeginterferon, the ratio of JAK2-mutated to wild-type colonies grown from bone marrow progenitors was reduced by 64%, compared to 25% in patients receiving hydroxyurea. This study shows that ropeginterferon has a potent targeted activity against JAK2-mutant cells and is able to drastically reduce the proportion of malignant progenitors in patients treated with this drug.

Hydroxyurea Associated Cutaneous Lesions: A Case Report

BACKGROUND

Hydroxyurea (HU) is an antimetabolite agent that interferes with the S-phase of cellular replication and inhibits DNA synthesis, with little or no effect on RNA or protein synthesis. It is used in the treatment of many myeloproliferative disorders (MD) and is particularly a first line treatment drug for intermediate to high-risk essential thrombocythemia. Although safe and very well tolerated by the patients suffering from MD, there have been numerous reports of a broad palette of cutaneous side effects associated with prolonged intake of the medication. These may include classical symptoms such as xerosis, diffuse hyperpigmentation, brown-nail discolouration, stomatitis and scaling of the face, hands, and feet or more serious side effects such as actinic keratosis lesions, leg ulcers and multiple skin carcinomas.

CASE REPORT

We report a case of a 52-year-old man, on long-term therapy with HU for essential thrombocytosis, with several concurrent skin lesions. Despite the perennial use of HU, the cutaneous changes were neglected. The local dermatological examination revealed oval perimalleolar ulcer on the right leg, with dimensions 6 x 4 cm, clearly demarcated from the surroundings with regular margins, periulcerous erythema, with very deep and highly fibrinous bed of the ulcer, positive for bacterial infection. The ulcer was treated with topical wound therapy with alginate and parenteral antibiotics. The extended dermatological screening also showed two nummular lesions in the right brachial region, presenting as erythematous papules with sharp margins from the surrounding skin, gritty desquamation and dotted hyperpigmentations inside the lesion. Further dermoscopy and biopsy investigations confirmed a diagnosis of basal cell carcinoma. Nasal actinic keratosis was also noted. The patient was advised for discontinuing or substituting the HU therapy.

CONCLUSION

We present this case to draw attention to the various cutaneous side effects that occur with perennial HU use and suggest an obligatory reference to a dermatological consult.

A Novel Acquired t(2;4)(q36.1;q24) with a Concurrent Submicroscopic del(4)(q23q24) in An Adult with Polycythemia Vera

Background: Polycythemia vera (PV) is a clonal myeloid stem cell disease characterized by a growth-factor independent erythroid proliferation with an inherent tendency to transform into overt acute myeloid malignancy. Approximately 95% of the PV patients harbor the JAK2V617F mutation while less than 35% of the patients harbor cytogenetic abnormalities at the time of diagnosis. Methods and Results: Here we present a JAK2V617F positive PV patient where G-banding revealed an apparently balanced t(2;4)(q35;q21), which was confirmed by 24-color karyotyping. Oligonucleotide array-based Comparative Genomic Hybridization (aCGH) analysis revealed an interstitial 5.4 Mb large deletion at 4q23q24. Locus-specific fluorescent in situ hybridization (FISH) analyses confirmed the mono-allelic 4q deletion and that it was located on der(4)t(2;4). Additional locus-specific bacterial artificial chromosome (BAC) probes and mBanding refined the breakpoint on chromosome 2. With these methods the karyotype was revised to 46,XX,t(2;4)(q36.1;q24)[18]/46,XX[7]. Conclusions: This is the first report on a PV patient associated with an acquired novel t(2;4)(q36.1;q24) and a concurrent submicroscopic deletion del(4)(q23q24). The study also underscores the benefit of combined usage of FISH and oligo-based aCGH analysis in characterizing chromosomal abnormalities. The present findings provide additional clues to unravel important molecular pathways in PV to obtain the full spectrum of acquired chromosomal and genomic aberrations, which eventually may improve treatment options.