Polycythemia vera and essential thrombocythemia: 2015 update on diagnosis, risk-stratification and management

Validation of the revised International Prognostic Score of Thrombosis for Essential Thrombocythemia (IPSET-thrombosis) in 585 Mayo Clinic patients

The primary objective of treatment in essential thrombocythemia (ET) is to prevent thromboembolic complications. In this regard, advanced age and thrombosis history have long distinguished "low" from "high" risk patients. More recently, JAK2V617F and cardiovascular (CV) risk factors were identified as additional modifiers, leading to the development of a 3-tiered International Prognostic Score of Thrombosis for ET (IPSET-thrombosis): "low," "intermediate," and "high". The international data set used to develop IPSET-thrombosis was recently re-analyzed in order to quantify the additional pro-thrombotic effect of JAK2V617F and CV risk factors in specific risk subcategories. The revised IPSET-thrombosis identified four risk categories based on three adverse variables (thrombosis history, age >60 years and JAK2V617F): very low (no adverse features), low (presence of JAK2V617F), intermediate (age >60 years) and high (presence of thrombosis history or presence of both advanced age and JAK2V617F). In this study of 585 patients with ET (median age 68 years; 61% female), we validated the revised IPSET-thrombosis by confirming significant differences in thrombosis risk between "very low" and "low" (HR 2.4, 95% CI 1.1 - 5.3) and between "intermediate" and "high" (HR 2.3, 95% CI 1.1 - 5.2) risk patients. Furthermore, in multivariable analysis, only JAK2V617F (HR=1.8, CI= 1.07 - 2.94) and history of thrombosis (HR=2.1, CI= 1.20 - 3.58) were independently predictive of future thrombotic events. The revised IPSET-thrombosis needs confirmation in prospective studies, especially in terms of risk-adapted therapy that includes the need for aspirin therapy in very low risk, twice-daily aspirin therapy for low risk and cytoreductive therapy for low or intermediate risk patients.

Calreticulin-mutant proteins induce megakaryocytic signaling to transform hematopoietic cells and undergo accelerated degradation and Golgi-mediated secretion

Background

Somatic calreticulin (CALR), Janus kinase 2 (JAK2), and thrombopoietin receptor (MPL) mutations essentially show mutual exclusion in myeloproliferative neoplasms (MPN), suggesting that they activate common oncogenic pathways. Recent data have shown that MPL function is essential for CALR mutant-driven MPN. However, the exact role and the mechanisms of action of CALR mutants have not been fully elucidated.

Methods

The murine myeloid cell line 32D and human HL60 cells overexpressing the most frequent CALR type 1 and type 2 frameshift mutants were generated to analyze the first steps of cellular transformation, in the presence and absence of MPL expression. Furthermore, mutant CALR protein stability and secretion were examined using brefeldin A, MG132, spautin-1, and tunicamycin treatment.

Results

The present study demonstrates that the expression of endogenous Mpl, CD41, and the key megakaryocytic transcription factor NF-E2 is stimulated by type 1 and type 2 CALR mutants, even in the absence of exogenous MPL. Mutant CALR expressing 32D cells spontaneously acquired cytokine independence, and this was associated with increased Mpl mRNA expression, CD41, and NF-E2 protein as well as constitutive activation of downstream signaling and response to JAK inhibitor treatment. Exogenous expression of MPL led to constitutive activation of STAT3 and 5, ERK1/2, and AKT, cytokine-independent growth, and reduction of apoptosis similar to the effects seen in the spontaneously outgrown cells. We observed low CALR-mutant protein amounts in cellular lysates of stably transduced cells, and this was due to accelerated protein degradation that occurred independently from the ubiquitin-proteasome system as well as autophagy. CALR-mutant degradation was attenuated by MPL expression. Interestingly, we found high levels of mutated CALR and loss of downstream signaling after blockage of the secretory pathway and protein glycosylation.

Conclusions

These findings demonstrate the potency of CALR mutants to drive expression of megakaryocytic differentiation markers such as NF-E2 and CD41 as well as Mpl. Furthermore, CALR mutants undergo accelerated protein degradation that involves the secretory pathway and/or protein glycosylation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-016-0275-0) contains supplementary material, which is available to authorized users.

Erdheim-Chester Disease With Multiorgan Involvement, Following Polycythemia Vera: A Case Report

Erdheim-Chester disease is a rare form of non-Langerhans cell histiocytosis characterized by the migration and infiltration of lipid-laden CD68, CD1a and S100 histiocytes to various target organs, which leads to the disruption of physiological tissue architecture and reactive fibrosis, and thus impairs organ function.We describe the first case of a patient with Erdheim-Chester disease with multiorgan involvement developed after 6 years from polycythemia vera diagnosis. During the follow-up, an abdominal ultrasound scan revealed the presence of dense, bilateral perinephric infiltration. A computed tomographic guided core biopsy was performed in order to identify the histological nature of this lesion, and a morphological analysis demonstrated the accumulation of foamy histiocytes surrounded by fibrosis. The BRAFV600E mutation was detected, and a diagnosis of Erdheim-Chester disease was made.The extreme rarity of Erdheim-Chester disease strongly suggests the existence of potentially common element(s) that may have contributed to the pathogenesis of both disorders. Obviously, further studies are needed to clarify the mutual roles and effects of JAK2 and BRAF mutations in this patient, as well as their possible therapeutic implications.

High rate of recurrent venous thromboembolism in patients with myeloproliferative neoplasms and effect of prophylaxis with vitamin K antagonists

The optimal duration of treatment with vitamin K antagonists (VKA) after venous thromboembolism (VTE) in patients with Philadelphia-negative myeloproliferative neoplasms (MPNs) is uncertain. To tackle this issue, we retrospectively studied 206 patients with MPN-related VTE (deep venous thrombosis of the legs and/or pulmonary embolism). After this index event, we recorded over 695 pt-years 45 recurrences, venous in 36 cases, with an incidence rate (IR) of 6.5 per 100 pt-years (95% confidence interval (CI): 4.9-8.6). One hundred fifty-five patients received VKA; the IR of recurrent thrombosis per 100 pt-years was 4.7 (95% CI: 2.8-7.3) on VKA and 8.9 (95% CI: 5.7-13.2) off VKA (P=0.03). In patients receiving VKA, the IR of recurrent thrombosis per 100 pt-years was 5.3 (95% CI: 3.2-8.4) among 108 patients on long-term VKA and 12.8 (95% CI: 7.3-20.7) after discontinuation among the 47 who ceased treatment (P=0.008), with a doubled risk of recurrence after stopping VKA (hazard ratio: 2.21, 95% CI: 1.19-5.30). The IR of major bleeding per 100 pt-years was 2.4 (95%: CI: 1.1-4.5) on VKA and 0.7 (95% CI: 0.08-2.5) off VKA (P=0.08). In conclusion, in MPN patients with VTE recurrent thrombosis is significantly reduced by VKA and caution should be adopted in discontinuation; however, the incidence of recurrence on treatment remains high, calling for clinical trials aimed to improve prophylaxis in this setting.

Pruritus in primary myelofibrosis: management options in the era of JAK inhibitors

Primary myelofibrosis (PMF)-associated pruritus is often severe and requires treatment. Fifty-one patients with bone marrow-proven PMF with associated pruritus were identified from a primary cohort of patients with PMF (n = 566) seen at our institution. We conducted a retrospective review of the clinical characteristics, severity of pruritus, type of treatment, and response of these patients. Thirty-two out of 51 patients (63 %) reported severe PMF-associated pruritus and required a total of 108 treatment episodes, with complete response (CR), partial response (PR) and no response (NR) observed in 22, 23, and 55 % of episodes, respectively. The most common treatment categories included JAK inhibitors (n = 19), anti-depressants (n = 18), and antihistamines (n = 17). Highest CR rates were observed in patients treated with a JAK inhibitor (53 %) and immunomodulatory drugs (IMiDS (50 %)). Emerging targeted therapies may result in better symptom control and higher response rates in patients suffering from severe PMF-associated pruritus.

Multicenter Retrospective Analysis of Turkish Patients with Chronic Myeloproliferative Neoplasms

Objective:

Chronic myeloproliferative neoplasms (CMPNs) that include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) are Philadelphia-negative malignancies characterized by a clonal proliferation of one or several lineages. The aim of this report was to determine the demographic features, disease characteristics, treatment strategies, and survival rates of patients with CMPNs in Turkey.

Materials and Methods:

Across all of Turkey, 9 centers were enrolled in the study. We retrospectively evaluated 708 CMPN patients’ results including 390 with ET, 213 with PV, and 105 with PMF.

Results:

The JAK2V617F mutation was found positive in 86% of patients with PV, in 51.5% of patients with ET, and in 50.4% of patients with PMF. Thrombosis and bleeding at diagnosis occurred in 20.6% and 7.5% of PV patients, 15.1% and 9% of ET patients, and 9.5% and 10.4% of PMF patients, respectively. Six hundred and eight patients (85.9%) received cytoreductive therapy. The most commonly used drug was hydroxyurea (89.6%). Leukemic and fibrotic transformations occurred at rates of 0.6% and 13.2%. The estimated overall survival in PV, ET, and PMF patients was 89.7%, 85%, and 82.5% at 10 years, respectively. There were no significant differences between survival in ET, PV, and PMF patients at 10 years.

Conclusion:

Our patients’ results are generally compatible with the literature findings, except for the relatively high survival rate in PMF patients. Hydroxyurea was the most commonly used cytoreductive therapy. Our study reflects the demographic features, patient characteristics, treatments, and survival rates of Turkish CMPN patients.

Disordered haematopoiesis and athero-thrombosis

Atherosclerosis, the major underlying cause of cardiovascular disease, is characterized by a lipid-driven infiltration of inflammatory cells in large and medium arteries. Increased production and activation of monocytes, neutrophils, and platelets, driven by hypercholesterolaemia and defective high-density lipoproteins-mediated cholesterol efflux, tissue necrosis and cytokine production after myocardial infarction, or metabolic abnormalities associated with diabetes, contribute to atherogenesis and athero-thrombosis. This suggests that in addition to traditional approaches of low-density lipoproteins lowering and anti-platelet drugs, therapies directed at abnormal haematopoiesis, including anti-inflammatory agents, drugs that suppress myelopoiesis, and excessive platelet production, rHDL infusions and anti-obesity and anti-diabetic agents, may help to prevent athero-thrombosis.

Clinico-Epidemiological Profile of Patients with Polycythaemia Rubra Vera - a Five Year Experience from a Tertiary Care Center

BACKGROUND

Polycythaemia rubra vera (PV) is a Philadelphia chromosome negative myeloproliferative neoplasm characterized by increased red cell production, independent of the mechanisms that regulate normal erythropoiesis. The aim of this study was to analyze the clinico-epidemiological profile of Pakistani patients with PV.

MATERIALS AND METHODS

In this retrospective cross sectional study, 26 patients with PV were enrolled from January 2010 to December 2014. They were diagnosed based on WHO criteria.

RESULTS

The mean age was 53.4±9.31 years (range 36-72) and the male to female ratio was 2:1. Overall 30.7% of patients were asymptomatic. In symptomatic patients, major complaints were headache (30.8%), abdominal discomfort (23.1%), blurred vision (15.3%), pruritus (11.5%) and vascular incidents (11.5%). Physical examination revealed plethoric face and splenomegaly as predominant findings, detected in 34.6% and 30.7%, respectively, with the mean splenic span of 15.9±2.04cm. The mean hemoglobin was 18.1±1.9 g/dl with the mean hematocrit of 55.6±8.3%. The mean total leukocyte count was 12.8±7.1x109/l and the platelet count 511±341.9x109/l. Mean erythrocyte sedimentation rate was 3.5±1.22mm/hr. Serum lactate dehydrogenase, serum creatinine and uric acid were 552.7±309.2, 0.8±0.17 and 6.60±1.89 respectively.

CONCLUSIONS

PV in Pakistani patients, unlike in the West, is seen in a moderately young population. The disease is frequently seen in male gender and primarily patients present with symptoms related to hyperviscosity.

Somatic JAK-2 V617F Mutational Analysis in Polycythemia Rubra Vera: a Tertiary Care Center Experience

BACKGROUND

Polycythemia rubra vera (PV), being a primary polycythemia, is caused by neoplastic proliferation of erythroid, megakaryocytic and granulocytic lineages which result in panmyelosis. PV patients have a somatic acquired mutation in the Janus kinase (JAK2) pathway, rendering cell proliferation independent of the normal regulatory mechanisms that regulate erythropoiesis. The rational of this study was to determine the prevalence of the JAK-2 V617F mutation in Pakistani patients with PV.

MATERIALS AND METHODS

In this cross sectional study, 26 patients with PV were enrolled from January 2010 to December 2014. Patients were diagnosed based on WHO criteria for PV. All were screened for G-T point mutation (V617F) in the JAK2 gene on chromosome 9 by an allele specific PCR.

RESULTS

The mean age was 53.4±9.31 years (range 36-72) and the male to female ratio was 2:1. The frequency of JAK2 V617F positivity in our PV patients was found to be 92.3%. Overall 30.7% of patients were asymptomatic and remaining 69.3% presented with symptomatic disease. The mean hemoglobin was 18.1±1.9g/dl with the mean hematocrit of 55.6±8.3%. The mean total leukocyte count was 12.8±7.1x109/l and the platelet count was 511±341.9x109/l. A positive correlation of JAK2 V617F mutation was established with high TLC count (P=0.01). No correlation of JAK2 V617F could be established with age or gender (P>0.05).

CONCLUSIONS

The JAK2 V617F mutation frequency in our PV patients was similar to those reported internationally. Screening for the mutation in all suspected PV cases could be beneficial in differentiating patients with reactive and clonal erythrocytosis.

Poly (ADP-Ribose) Polymerase Inhibitor Hypersensitivity in Aggressive Myeloproliferative Neoplasms

PURPOSE

DNA repair defects have been previously reported in myeloproliferative neoplasms (MPN). Inhibitors of PARP have shown activity in solid tumors with defects in homologous recombination (HR). This study was performed to assess MPN sensitivity to PARP inhibitors ex vivo

EXPERIMENTAL DESIGN

HR pathway integrity in circulating myeloid cells was evaluated by assessing the formation of RAD51 foci after treatment with ionizing radiation or PARP inhibitors. Sensitivity of MPN erythroid and myeloid progenitors to PARP inhibitors was evaluated using colony formation assays.

RESULTS

Six of 14 MPN primary samples had reduced formation of RAD51 foci after exposure to ionizing radiation, suggesting impaired HR. This phenotype was not associated with a specific MPN subtype, JAK2 mutation status, or karyotype. MPN samples showed increased sensitivity to the PARP inhibitors veliparib and olaparib compared with normal myeloid progenitors. This hypersensitivity, which was most pronounced in samples deficient in DNA damage-induced RAD51 foci, was observed predominantly in samples from patients with diagnoses of chronic myelogenous leukemia, chronic myelomonocytic leukemia, or unspecified myelodysplastic/MPN overlap syndromes.

CONCLUSIONS

Like other neoplasms with HR defects, MPNs exhibit PARP inhibitor hypersensitivity compared with normal marrow. These results suggest that further preclinical and possibly clinical study of PARP inhibitors in MPNs is warranted. Clin Cancer Res; 22(15); 3894-902. ©2016 AACR.

From Philadelphia-Negative to JAK2-Positive: Effect of Genetic Discovery on Risk Stratification and Management

The 2005 discovery of the JAK2 mutation redefined the diagnosis and natural history of myeloproliferative neoplasms (MPNs). Most importantly, this improvement in the pathobiologic conceptualization has focused our evolution of this field from being defined as what it is not (e.g., Philadelphia [Ph]-negative) to what it is (e.g., JAK2-positive, CALR-positive) in the majority of MPN cases. In the ensuing 10 years, the field has experienced a paradigm shift in terms of understanding of the biologic basis of the development of MPNs, an explosion of knowledge of the genetics of MPNs, and has translated disease knowledge into effective targeted therapies. With greater uniformity and agreement on the diagnosis and differences among the individual MPNs, augmented by improved cytogenetic and molecular classification, attention has turned now to addressing the need for uniformity in risk stratification of patients in the clinic for both disease complications and disease transformation. This article will highlight the developments in the field with regard to risk stratification and prognostication in MPNs with focus on the clinical aspects of the patient who presents with either essential thrombocytosis (ET), polycythemia vera (PV), or myelofibrosis (MF).

Myeloproliferative neoplasms: A decade of discoveries and treatment advances

Myeloproliferative neoplasms (MPN) are clonal stem cell diseases, first conceptualized in 1951 by William Dameshek, and historically included chronic myeloid leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). In 1960, Nowell and Hungerford discovered an invariable association between the Philadelphia chromosome (subsequently shown to harbor the causal BCR-ABL1 mutation) and CML; accordingly, the term MPN is primarily reserved for PV, ET, and PMF, although it includes other related clinicopathologic entities, according to the World Health Organization (WHO) classification system. In 2005, William Vainchenker and others described a Janus kinase 2 mutation (JAK2V617F) in MPN and this was followed by a series of additional descriptions of mutations that directly or indirectly activate JAK-STAT: JAK2 exon 12, myeloproliferative leukemia virus oncogene (MPL) and calreticulin (CALR) mutations. The discovery of these, mostly mutually exclusive, "driver" mutations has contributed to revisions of the WHO diagnostic criteria and risk stratification in MPN. Mutations other than JAK2, CALR and MPL have also been described in MPN and shown to provide additional prognostic information. From the standpoint of treatment, over the last 50 years, Louis Wasserman from the Unites States and Tiziano Barbui from Italy had skillfully organized and led a number of important clinical trials, whose results form the basis for current treatment strategies in MPN. More recently, allogeneic stem cell transplant, as a potentially curative treatment modality, and JAK inhibitors, as palliative drugs, have been added to the overall therapeutic armamentarium in myelofibrosis. In the current review, I will summarize the important advances made in the last 10 years regarding the science and practice of MPN.

Splanchnic vein thrombosis and myeloproliferative neoplasms: molecular-driven diagnosis and long-term treatment

Splanchnic vein thrombosis (SVT) encompasses Budd-Chiari syndrome (BCS), extrahepatic portal vein obstruction (EHPVO), and mesenteric vein thrombosis. Philadelphia-negative myeloproliferative neoplasms (MPNS) are the leading systemic cause of non-cirrhotic and non-malignant SVT and are diagnosed in 40% of BCS patients and one-third of EHPVO patients. In SVT patients the molecular marker JAK2 V617F is detectable up to 87% of those with overt MPN and up to 26% of those without. In the latter, other MPN molecular markers, such as mutations in JAK2 exon 12, CALR and MPL genes, are extremely rare. Immediate anticoagulation with heparin is used to treat acute patients. Upon clinical deterioration, catheter-directed thrombolysis or a transjugular intrahepatic portosystemic shunt is used in conjunction with anticoagulation. Orthotopic liver transplantation is the only reliable option in BCS patients with a lack of a response to other treatments, without contraindication due to MPN. Long-term oral anticoagulation with vitamin K-antagonists (VKA) is recommended in all SVT patients with the MPN-related permanent prothrombotic state; the benefits of adding aspirin to VKA are uncertain. Cytoreduction is warranted in all SVT patients with an overt MPN, but its appropriateness is doubtful in those with molecular MPN without hypercythaemia.

Coexistence of follicular lymphoma and an unclassifiable myeloproliferative neoplasm in a treatment-naïve patient: A case report

Myeloproliferative neoplasms are associated with lymphoproliferative diseases following the administration of cytotoxic drugs or exposure to radiation, but are rare prior to therapy. The present study reports the case of a 61-year-old female with a history of transient ischemic attack. The patient, who presented with a palpable mass in the epitrochlear area of the left arm, was simultaneously diagnosed with follicular lymphoma and an unclassifiable myeloproliferative neoplasm. Excisional lymph node biopsy revealed stage I follicular lymphoma (grade 1). Laboratory findings demonstrated leukocytosis, erythrocytosis, thrombocytosis and decreased erythropoietin. Biopsy of the bone marrow revealed hypercellularity, with predominance of erythroid cells, and large polylobated megakaryocytes with increased mitotic figures, but no evidence of lymphomatous infiltration. The janus kinase 2 V617F mutation was also detected in the cells derived from the bone marrow specimen. Following local excision of the lymph node in the left epitrochlear area, radiation was delivered to the involved field, at a dose of 24 Gy in 12 fractions. The patient was started on hydroxyurea (1 g twice per day, orally) 2 weeks subsequent to radiotherapy, and was administered 500 mg twice per day as maintenance therapy. At the six-month follow-up, the white blood cell count, hemoglobin levels and platelet count had reduced, and the patient was in a healthy condition. A computed tomography scan of the neck, chest and abdomen indicated no abnormalities. To the best of our knowledge, the present study is the first case report of follicular lymphoma coexisting with an unclassifiable myeloproliferative neoplasm in a previously healthy patient. Molecular and genetic studies are required to further evaluate this infrequent disease association.

Frequency and prognostic value of resistance/intolerance to hydroxycarbamide in 890 patients with polycythaemia vera

The clinical significance of resistance/intolerance to hydroxycarbamide (HC) was assessed in a series of 890 patients with polycythaemia vera (PV). Resistance/intolerance to HC was recorded in 137 patients (15·4%), consisting of: need for phlebotomies (3·3%), uncontrolled myeloproliferation (1·6%), failure to reduce massive splenomegaly (0·8%), development of cytopenia at the lowest dose of HC to achieve a response (1·7%) and extra-haematological toxicity (9%). With a median follow-up of 4·6 years, 99 patients died, resulting in a median survival of 19 years. Fulfilling any of the resistance/intolerance criteria had no impact on survival but when the different criteria were individually assessed, an increased risk of death was observed in patients developing cytopenia [Hazard ratio (HR): 3·5, 95% confidence interval (CI): 1·5-8·3, P = 0·003]. Resistance/intolerance had no impact in the rate of thrombosis or bleeding. Risk of myelofibrotic transformation was significantly higher in those patients developing cytopenia (HR: 5·1, 95% CI: 1·9-13·7, P = 0·001) and massive splenomegaly (HR: 9·1, 95% CI: 2·3-35·9, P = 0·002). Cytopenia at the lowest dose required to achieve a response was also an independent risk factor for transformation to acute leukaemia (HR: 20·3, 95% CI: 5·4-76·5, P < 0·001). In conclusion, the unified definition of resistance/intolerance to HC delineates a heterogeneous group of PV patients, with those developing cytopenia being associated with an adverse outcome.

Management of symptoms in polycythemia vera and essential thrombocythemia patients

The BCR-ABL-negative myeloproliferative neoplasms (MPNs) are clonal stem cell derived malignancies, which include polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis (MF). The MPNs are characterized by dysregulated JAK-STAT signaling pathways. PV and ET are associated with an increased risk of thrombo-hemorrhagic complications, risk of progression to MF and leukemia. Presentation of patients with PV and ET is variable and usually as a result of abnormal full blood count indices (raised hemoglobin and hematocrit, leukocytosis, and thrombocytosis). Presentation with thrombosis or splenomegaly occurs in ∼30% of patients. Historically thought of as indolent compared with MF, patients with PV and ET have significant disease symptom burden which does not directly correlate to the current clinical prognostic classifications. The mainstay of therapy is reserved for patients with high-risk disease and thus excludes a population of patients with significant symptom related morbidity impacting their quality-of-life and survival. Recent treatment strategies have aimed to incorporate disease burden assessment into the selection of therapeutic interventions such as JAK2 inhibitors and HDAC inhibitors. We will review the advances in the field of MPN symptom assessment and symptom burden experienced by ET and PV patients. We will also discuss the risk-stratified management of ET and PV patients alongside symptom assessment and the impact of potential novel therapies, for patients who fail to respond to conventional treatment.

Clinico-Hematological Profile and Risk Stratification in Patients with Essential Thrombocythemia: Experience from Pakistan

BACKGROUND

Essential thrombocythemia (ET) is a Philadelphia chromosome-negative myeloproliferative neoplasm characterized by sustained thrombocytosis and megakaryocytic hyperplasia. It is an uncommon hematological malignancy which primarily affects elderly individuals. The rational of this study was to determine its clinico-hematological profile along with risk stratification in Pakistan patients.

MATERIALS AND METHODS

In this retrospective cross sectional study, 21 patients with ET were enrolled from January 2011 to December 2014. Data was analyzed with SPSS version 21.

RESULTS

The mean age was 56.7 ± 19.0 years (range 18-87) and the male to female ratio was 1:1.1. Of the total, 62% of patients were above 50 years of age. Overall 61.9% were diagnosed incidentally and were asymptomatic. In symptomatic patients, major complaints were weakness (19%); erythromelalgia (14.2%), transit ischemic attack (9.5%) and gastrointestinal bleed (4.7%). The mean hemoglobin count was 11.7 ± 2.4 g/dl with a total leukocyte count of 13.3 ± 8.1 x 10(9)/l and platelets count of 1188.8 ± 522.2 x 10(9)/l. Serum lactate dehydrogenase, serum creatinine and uric acid were 454.3 ± 127.8, 1.2 ± 0.5 and 7.4 ± 3.4 respectively. According to risk stratification, 57.1% were in high risk; 23.8% in intermediate risk while 19.1% in low risk group.

CONCLUSIONS

ET in our patients in Pakistan, unlike in the West, is seen in a relatively young population. Primarily patients were asymptomatic and risk stratification revealed predominance of high risk disease in our setting.

Platelet Count and Major Bleeding in Patients Receiving Vitamin K Antagonists for Acute Venous Thromboembolism, Findings From Real World Clinical Practice

The outcome of patients with acute venous thromboembolism (VTE) and abnormal platelet count (PlC) at baseline has not been consistently studied. In real-world clinical practice, a number of patients with abnormal PlC receive vitamin K antagonists (VKAs) to treat acute VTE despite their higher risk of bleeding.We used the Registro Informatizado de Enfermedad TromboEmbólica registry database to compare the rate of major bleeding in patients receiving VKA for long-term therapy of acute VTE according to PlC levels at baseline. Patients were categorized as having very low (<100,000/μL), low (100,000-150,000/μL), normal (150,000-300,000/μL), high (300,000-450,000/μL), or very high (>450,000/μL) PlC at baseline.Of 55,369 patients recruited as of January 2015, 37,000 (67%) received long-term therapy with VKA. Of these, 611 patients (1.6%) had very low PlC, 4006 (10.8%) had low PlC, 25,598 (69%) had normal PlC, 5801 (15.6%) had high PlC, and 984 (2.6%) had very high PlC at baseline. During the course of VKA therapy (mean, 192 days), there were no differences in the duration or intensity (as measured by international normalized ratio levels) of treatment between subgroups. The rate of major bleeding was 3.6%, 2.1%, 1.9%, 2.1%, and 3.7%, respectively, and the rate of fatal bleeding was 0.98%, 0.17%, 0.29%, 0.34%, and 0.50%, respectively. Patients with very low or very high PlC levels were more likely to have severe comorbidities.We found a nonlinear "U-shaped" relationship between PlC at baseline and major bleeding during therapy with VKA for VTE. Consistent alteration of PlC values at baseline suggested a greater frailty.

Acquired JAK-2 V617F Mutational Analysis in Pakistani Patients with Essential Thrombocythemia

BACKGROUND

Essential thrombocythemia (ET) is a clonal hemopoietic stem cell myeloproliferative neoplasm characterized by persistent thrombocytosis along with megakaryocytic hyperplasia. In the last decade following the identification of an acquired JAK2 V617F mutation, there has been acceleration in our understanding of this disease. The rational of this study was to determine the mutational profile of JAK2 V617F in Pakistan patients with ET.

MATERIALS AND METHODS

In this retrospective cross sectional study, 21 patients with ET were enrolled from January 2011 to December 2014. Patients were diagnosed based on WHO criteria for essential thrombocythemia. Complete blood count was done on an automated hematology analyzer, while JAK2 V617F expression was evaluated by polymerase chain reaction.

RESULTS

The mean age was 56.7±19.0 years (range 18-87) and the male to female ratio was 1:1.1. The frequency of JAK2 V617F positivity in our ET patients was found to be 61.9%. The mean hemoglobin was 11.7±2.4 g/dl with a total leukocyte count of 13.3±8.1x109/l and a platelet count of 1188±522x109/l. Positive correlations for JAK2 V617F mutation were established with high TLC count and raised LDH (P<0.05). No correlation of JAK2 V617F could be established with age and gender (P>0.05).

CONCLUSIONS

JAK2 V617F mutation frequency in our ET patients was similar to those reported previously. Screening for the mutation in all suspected essential thrombocythemia cases could be beneficial in differentiating patients with reactive and clonal thrombocytosis.

MPNs as Inflammatory Diseases: The Evidence, Consequences, and Perspectives

In recent years the evidence is increasing that chronic inflammation may be an important driving force for clonal evolution and disease progression in the Philadelphia-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF). Abnormal expression and activity of a number of proinflammatory cytokines are associated with MPNs, in particular MF, in which immune dysregulation is pronounced as evidenced by dysregulation of several immune and inflammation genes. In addition, chronic inflammation has been suggested to contribute to the development of premature atherosclerosis and may drive the development of other cancers in MPNs, both nonhematologic and hematologic. The MPN population has a substantial inflammation-mediated comorbidity burden. This review describes the evidence for considering the MPNs as inflammatory diseases, A Human Inflammation Model of Cancer Development, and the role of cytokines in disease initiation and progression. The consequences of this model are discussed, including the increased risk of second cancers and other inflammation-mediated diseases, emphasizing the urgent need for rethinking our therapeutic approach. Early intervention with interferon-alpha2, which as monotherapy has been shown to be able to induce minimal residual disease, in combination with potent anti-inflammatory agents such as JAK-inhibitors is foreseen as the most promising new treatment modality in the years to come.

Oxidative status in treatment-naïve essential thrombocythemia: a pilot study in a single center

Oxidative stress (OS), due to pro-oxidant species [reactive oxygen species (ROS)] excess not counterbalanced by endogenous antioxidant molecules [e.g., reduced glutathione (GSH)], is involved in the pathogenesis of human cancers, but few data are available on essential thrombocythemia (ET). This study aims to investigate OS in ET off-therapy patients. Thirty ET treatment-naïve patients were compared with 26 age-matched and gender-matched controls. Serum ROS, urinary 8-hydroxydeoxyguanosine, full blood GSH levels, and reduced/oxidized GSH ratio (GSH/GSSG) were measured. Data were adjusted for gender, age, JAK2 mutational status, smoking, dyslipidemia, or hypercholesterolemia requiring drug therapy, antiplatelet therapy, treatment with acetylsalicylic acid, high-sensitive C-reactive protein levels, and absolute monocyte count. ROS and GSH levels were increased in both patients and controls. Patients showed increased GSSG (p = 0.05), reduced GSH/GSSG ratio (p = 0.08), and similar 8-hydroxydeoxyguanosine levels when compared with controls. No differences in OS parameters were found between JAK2-positive and JAK2-negative patients. Confounding factors did not modify the results. Our study suggests an OS condition in a cohort of treatment-naïve ET patients, not associated with JAK2 mutational status or with chronic inflammation situation. GSH/GSSG ratio, altered in ET patients because of increased GSSG levels, showed the presence of higher GSH levels in ET than controls as a possible compensatory mechanism of an excess of pro-oxidant production. Copyright © 2015 John Wiley & Sons, Ltd.

Persistent Reactive Thrombocytosis May Increase the Risk of Coronary Artery Disease Among Inflammatory Bowel Disease Patients

BACKGROUND

IBD patients are at increased risk of coronary artery disease in the absence of traditional risk factors. However, the disease-related risk factors remain poorly understood although increased inflammation seems to increase cardiovascular disease risk in IBD. Thrombocytes are involved in the pathogenesis of coronary artery disease, and a subset of IBD patients have reactive thrombocytosis.

AIM

The aim of our study was to investigate the effect of persistent reactive thrombocytosis on the development of coronary artery disease in IBD.

METHODS

We evaluated a retrospective cohort of 2525 IBD patients who were evaluated at the Henry Ford hospital from 2000 to 2004. We performed a case-control study comparing patients with persistent thrombocytosis and patients without persistent thrombocytosis. Cases (n = 36) and controls (n = 72) were matched for age and gender. Coronary artery disease incidence was compared between the two groups.

RESULTS

Cases (n = 36) and controls (n = 72) were matched for age and gender. Cases and controls were similar in age at onset of IBD (41.5 vs. 35.5, p value 0.11) and smoking status (33.3 vs. 27.8%, p value 0.66). Persistent thrombocytosis was less common among Caucasian patients (44.44 vs. 62.5%, p value 0.09) and more common in patients who had exposure to steroids during the study follow-up period. Coronary artery disease occurred in 13 (36.1%) patients with persistent thrombocytosis compared to only seven (9.7%) patients in the control group.

CONCLUSIONS

Persistent reactive thrombocytosis among IBD patients is associated with increased risk of coronary artery disease. Further studies should characterize the clinical and molecular associations of this phenomenon and determine appropriate therapeutic measures.

The Multifaceted Clinical Readouts of Platelet Inhibition by Low-Dose Aspirin

Inactivation of platelet cyclooxygenase (COX)-1 by low-dose aspirin leads to long-lasting suppression of thromboxane (TX) A2 production and TXA2-mediated platelet activation and aggregation. This effect is necessary and sufficient to explain aspirin's unique (among other COX-1 inhibitors) effectiveness in preventing atherothrombosis, as well as its shared (with other antiplatelet agents) bleeding liability. However, different mechanisms of action have been suggested to explain other beneficial effects of aspirin, such as prevention of venous thromboembolism, chemoprevention of colorectal (and other) cancers, and reduced risk of dementia. These mechanisms include acetylation of other proteins in blood coagulation, inhibition of COX-2 activity, and other COX-independent mechanisms. The intent of this review is to develop the concept that the multifaceted therapeutic effects of low-dose aspirin may reflect pleiotropic consequences of platelet inhibition on pathophysiological tissue repair processes. Furthermore, the clinical implications of this concept will be discussed in terms of current clinical practice and future research.

Management of side effects of BCR/ABL-negative chronic myeloproliferative neoplasm therapies. Focus on anagrelide

Although hydroxyurea is considered the first-line cytoreductive therapy in high-risk patients with polycythemia vera or essential thrombocythemia, approximately 20-25% of patients develop resistance or intolerance and they need an alternative therapy. Anagrelide is the treatment of choice in patients with essential thrombocythemia intolerant or with resistance to hydroxyurea. Anagrelide is usually well tolerated. Although there is concern about the increased risk of cardiac side effects, in most cases these are mild, and easily manageable. In this paper, the available evidence about the management of patients with myeloproliferative neoplasms, with a special focus on the side effects of drug therapies is reviewed.

Smoking as a contributing factor for development of polycythemia vera and related neoplasms

Smoking may be associated with accelerated erythropoiesis, leukocytosis and thrombocytosis, which are also hallmarks in patients with polycythemia vera, essential thrombocythemia and early stages of myelofibrosis (MPNs). The JAK-STAT and NF-κB signaling pathways are activated in both smokers and in patients with MPNs. Additionally, both share elevated levels of several proinflammatory cytokines, in vivo activation of leukocytes and platelets, endothelial dysfunction and increased systemic oxidative stress. Based upon experimental, epidemiological and clinical data it is herein argued and discussed, if smoking may be involved in MPN pathogenesis, considering most recent studies and reviews which are supportive of the concept that chronic inflammation with NF-κB activation and oxidative stress may have a major role - both as triggers but also as the driving force for clonal expansion in MPNs.

[Vascular myeloproliferative neoplasm with normal cell blood count: Exploration and medical management]

Negative BCR ABL myeloproliferative neoplasm (MPN) such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (MFP) are clonal hematological malignancies and may lead to a high risk of venous, arterial or microcirculatory thrombosis. Atypical sites of thrombosis can sometimes reveal the neoplasm disorder. Their diagnoses are a major issue because of the propensity to develop acute myeloid leukemia and/or myelofibrosis. The acquired JAK2V617F variant (Janus kinase 2; 9p24) is a prevalent MPN and also a sensitive marker for PV diagnosis (95% positive mutation), but not specific since found in approximately 50% of patients with ET and MFP.

PATIENT AND METHODS

We present a diagnostic and a therapeutic approach based on one patient with microcirculatory ischemic manifestations in the toes, and who had strictly normal cell blood counts and was positive for JAK2V617F mutation: thrombotic risk factor evaluation; bone marrow biopsy; red cell adhesion assays. These experimental assays are promising for the development of new therapeutics in MPN; they assess red cell adherence to the vascular endothelium after the phosphorylation of Lu/BCAM subsequent to a positive JAK2V617F mutation.

RESULTS

Compared with controls, our patient exhibited increased Lu/BCAM receptor phosphorylation and red blood cell adhesion.

CONCLUSION

This development may lead to improved care for patients with thrombotic manifestations, normal blood cell counts, and a positive JAK2V617F mutation: multidisciplinary management, including regular hematological monitoring, could lead to the introduction of a cytoreductive treatment.

Essential Thrombocythemia and Polycythemia Vera: Focus on Clinical Practice

Bone marrow (BM) morphologic features remain the cornerstone of diagnosis in both essential thrombocythemia (ET) and polycythemia vera (PV). In addition, recently discovered mutations, such as JAK2, CALR, and MPL, have proven useful in facilitating the diagnostic process. A JAK2 mutation is expected in PV, and its absence makes the diagnosis unlikely. However, JAK2 mutations also occur in about 60% of patients with ET, which underlines the need for BM examination in distinguishing JAK2-mutated ET from PV when the hemoglobin/hematocrit level is diagnostically equivocal (ie, as in "masked" PV). Most patients with JAK2-unmutated ET express CALR or MPL mutations, with respective estimated incidences of 22% and 3%, while approxmately 15% are wild-type for all 3 mutations (ie, they are triple-negative). As such, CALR first, followed by MPL if CALR is absent, mutation screening is appropriate in the diagnostic work-up of JAK2-unmutated ET but does not replace the need for BM morphologic examination in (1) confirming the diagnosis in triple-negative ET and (2) distinguishing ET from other myeloproliferative neoplasms that share the same mutations, including masked PV and early/prefibrotic myelofibrosis. Young patients (aged < 60 years) with ET or PV and no history of thrombosis are conventionally regarded as having "low-risk" disease. First-line treatment in low-risk PV is phlebotomy to achieve a hematocrit target of 45% and low-dose aspirin, and first-line treatment in ET is observation alone in the absence of additional risk factors for arterial thrombosis (ie, JAK2 mutation and cardiovascular risk factors) or low-dose aspirin therapy, once or twice daily, in the presence of one or both of these risk factors, respectively. Cytoreductive therapy is indicated in high-risk (patients aged ≥ 60 years or a history of thrombosis) PV or ET in the form of hydroxyurea as first-line and interferon alfa or busulfan as second-line drugs of choice. We do not use ruxolitinib in patients with PV unless they have severe pruritus or symptomatic splenomegaly that is proved to be refractory to hydroxyurea, interferon alfa, and busulfan.

Neurological symptoms in essential thrombocythemia: impact of JAK2V617F mutation and response to therapy

Patients with essential thrombocythemia (ET) often suffer from neurological symptoms (NS) not ever resulting from previous thrombotic cerebral events (TCE). We reported NS occurred in 282 patients, in order to identify the factors influencing ET-related NS in the absence of TCE, and the response to therapy. Overall, 116 of 282 patients (41%) presented NS; 101 of them (87%) reported subjective transient and fluctuating NS, without concurrent TCE, which we defined as ET-related NS, by frequency: cephalalgia, chronic paresthesias, dizziness or hypotension, visual disturbances, and tinnitus. In univariate analysis, ET-related NS resulted more frequently in young people (P = 0.017) and in females (P = 0.025). We found a higher prevalence of JAK2V617F mutation in ET-related NS patients (P = 0.021). In multivariate analysis, gender (P = 0.024) and JAK2V617F mutation (P = 0.041) remained significantly associated with the development of ET-related NS, with a risk of about four times higher for JAK2V617F-mutated patients (OR = 3.75). Ninety-seven of 101 patients with ET-related NS received an antiplatelet (AP) agent at the time of NS, whereas only selected high-risk ET-related NS patients were treated with a cytoreductive drug, according to the published guidelines and similarly to patients without NS. We observed that only 32 of 97 (33%) patients with ET-related NS achieved a complete response after AP treatment. Among the 65 non-responder patients, 36 (55.4%) improved NS after the introduction of cytoreductive therapy; therefore, the addition of cytoreductive treatment should be considered in this setting.

Factors predisposing to acquired von Willebrand syndrome during the course of polycythemia vera - retrospective analysis of 142 consecutive cases

INTRODUCTION

The aim of this study was to verify if PV patients with and without avWS differ in terms of their baseline clinical parameters.

MATERIAL AND METHODS

The study included 142 consecutive patients with PV. avWS was diagnosed on the basis of abnormally low levels of von Willebrand factor and other routine tests. Patients with and without concomitant avWS were compared in terms of their demographic characteristics, present and past medical histories and laboratory parameters.

RESULTS

Concomitant avWS was found in 17 PV patients (12.0%). Individuals with avWS have been diagnosed with PV at significantly younger age than those without, and significantly less often were in remission at the time of testing for bleeding disorders. Most of them (58.8%) presented with typical signs of bleeding disorder. Moreover, they showed significantly higher erythrocyte, leukocyte and platelet counts, abnormalities of coagulation profile corresponding to defects of primary hemostasis and abnormal values of all parameters used in the routine diagnosis of avWS.

CONCLUSIONS

Even every tenth patient with PV may develop avWS. Young age at diagnosis of PV and poor response to previous treatment of this condition are potential risk factors of avWS that should be considered during history taking. Sings of bleeding disorder observed in a person with PV necessitate evaluation for avWS.

Ruxolitinib for the treatment of patients with polycythemia vera

Polycythemia vera (PV) is a hematopoietic proliferative disorder associated with Janus-associated kinase/signal transducer and activator of transcription pathway dysregulation resulting in erythrocytosis and, possibly, leukocytosis and thrombocytosis. Patients diagnosed with PV experience a broad range of symptoms associated with a reduced quality of life, often develop splenomegaly, and have an increased risk of death compared with age-matched subjects without PV. Current treatment options, notably hydroxyurea, help with disease management; however, insufficient efficacy or progressive resistance occurs in some patients, highlighting the need for new treatment options. Ruxolitinib is an oral JAK1/JAK2 inhibitor that has been evaluated in Phase II and III clinical trials in patients with PV, who are intolerant of or resistant to hydroxyurea. In this setting, ruxolitinib treatment has demonstrated normalization of blood cell counts, reduction in splenomegaly and improvements in PV-related symptom burden.

[Diagnosis of essential thrombocythemia after myocardial infarction and cardiac arrest: A case report]

Acute coronary syndrome is now a well-known disease, with codified treatments. The main presentation is chest pain, but more and more cases are revealed by cardiorespiratory arrest thanks to pre-hospital care. And, depending on the evolution in such situations, cardiocirculatory support techniques like extracorporeal membrane oxygenation (ECMO) can be implemented. If the more common cause of SCA is atherosclerosis, consequence of the combination of one or more cardiovascular risk factors, there are rare aetiologies, which include myeloproliferative syndromes, in particular essential thrombocythemia. We describe the case of a 34-year-old man presenting with anterior ST-elevation myocardial infarction complicated by an initial cardiac arrest, whose aetiology is unknown essential thrombocythemia, and its therapeutic management requiring circulatory support by ECMO and IMPELLA(®) techniques.

Refractory anemia with ring sideroblasts and RARS with thrombocytosis

DISEASE OVERVIEW

Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis (RARS-T).

DIAGNOSIS

RARS is a lower risk myelodysplastic syndrome (MDS) with dysplasia limited to the erythroid lineage, <5% bone marrow (BM) blasts and ≥15% BM RS. RARS-T is a provisional entity in the MDS/MPN (myeloproliferative neoplasm) overlap syndromes, with diagnostic features of RARS, along with a platelet count ≥450 × 10(9)/L and large atypical megakaryocytes similar to those observed in BCR-ABL1 negative MPN. Mutations and Karyotype: Mutations in the SF3B1 gene are seen in ≥80% of patients with RARS and RARS-T, and strongly correlate with the presence of BM RS; RARS-T patients have additional mutations such as, JAK2V617F (∼60%), MPL (<5%), and CALR (<5%). Cytogenetic abnormalities are uncommon in both RARS and RARS-T.

RISK STRATIFICATION

Most patients with RARS are stratified into lower risk groups by the International Prognostic Scoring System (IPSS) for MDS and the revised IPSS. Disease outcome in RARS-T is better than that of RARS, but worse than that of essential thrombocytosis. Both RARS and RARS-T have a low risk of leukemic transformation.

TREATMENT

Anemia and iron overload are complications in both diseases and are managed similar to lower risk MDS. Aspirin therapy is reasonable in RARS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs is uncertain. Case reports of RARS-T therapy with lenalidomide warrant additional studies.

Atypical venous thromboses in myeloproliferative neoplasias

We describe two patients who developed an extensive catheter-related upper extremity deep vein thrombosis and a cerebral venous sinus thrombosis, respectively. Both thrombotic complications occurred in the presence of an elevated platelet count. Subsequent detection of the JAK2 V617F and MPL mutations led to the diagnosis of a myeloproliferative neoplasia.

[Thrombotic events and significance of the IPSET thrombosis risk evaluation score in essential thrombocythaemia]

INTRODUCTION

Thrombo-haemorrhagic complications contribute to both morbidity and mortality in patients with essential thrombocythaemia.

AIM

The aim of the authors was to estimate the incidence of thrombotic events and to examine the clinical utility of IPSET thrombosis risk evaluation score against conventional two-categorical (low and high) risk assessment.

METHOD

A retrospective analysis was carried out on 155 patients with essential thrombocythaemia (106 females; median age, 61 years) in a period between 1999 and 2014.

RESULTS

The analysis revealed 55 (35.5%) major thrombotic events before and 25 (16.1%) major thrombotic complications after establishment of the haematologic diagnosis. Significant differences were observed in thrombosis-free survival between the different IPSET groups (p = 0.002).

CONCLUSIONS

The IPSET model was first examined in this cohort of patients with essential thrombocythaemia diagnosed in a single Hungarian haematologic centre. The results suggest that this score may provide more information than the conventional thrombosis risk assessment.