Polycythemia vera and essential thrombocythemia of intermediate-age: A real-life, multicenter analysis of first-line treatment approach.

BACKGROUND: The treatment of patients with polycythemia vera (PV) and essential thrombocythemia (ET) is conducted according to well-defined risk stratification systems. We hypothesized that adherence to the guidelines, namely the decision to refrain from introducing cytoreduction in non-high-risk patients, is particularly difficult in patients diagnosed when they are between 40 and 59 years of age (intermediate-age group). OBJECTIVES: To evaluate the group of intermediate-age PV and ET patients, focusing on a first-line treatment approach adapted at diagnosis. MATERIAL AND METHODS: The study group consisted of 308 PV and ET patients recruited from 6 Polish Adult Leukemia Group (PALG) Centers. Patients were analyzed with respect to disease phenotype, risk group, treatment approach, cardiovascular (CV) risk factors, and occurrence of bleeding or thrombosis. RESULTS: Overall, 74% of patients in the study group were started on cytoreduction at diagnosis, including 70% of the low-risk PV patients and 85-89% of the non-high-risk ET patients. Factors influencing the decision to start the treatment included higher hemoglobin (Hb) concentration (in PV) as well as higher platelet (PLT) count, and the presence of CV risk factors (in ET). Introducing cytoreduction at diagnosis had no impact on thrombotic events. Patients harboring CV risk factors experienced a higher incidence of complications both at diagnosis and follow-up, independently of the treatment strategy. CONCLUSIONS: We underline the low adherence to recommendations in the treatment of intermediate-age PV and ET patients. Moreover, we emphasize the importance of CV risk factors and stress their impact on disease phenotype in this patient population.

The molecular profile in patients with polycythemia vera and essential thrombocythemia is dynamic and correlates with disease's phenotype.

Introduction: Polycythemia vera (PV) and essential thrombocythemia (ET) are diseases driven by canonical mutations in JAK2, CALR, or MPL gene. Previous studies revealed that in addition to driver mutations, patients with PV and ET can harbor other mutations in various genes, with no established impact on disease phenotype. We hypothesized that the molecular profile of patients with PV and ET is dynamic throughout the disease. Methods: In this study, we performed a 37-gene targeted next-generation sequencing panel on the DNA samples collected from 49 study participants in two-time points, separated by 78-141 months. We identified 78 variants across 37 analyzed genes in the study population. Results: By analyzing the change in variant allele frequencies and revealing the acquisition of new mutations during the disease, we confirmed the dynamic nature of the molecular profile of patients with PV and ET. We found connections between specific variants with the development of secondary myelofibrosis, thrombotic events, and response to treatment. We confronted our results with existing conventional and mutation-enhanced prognostic systems, showing the limited utility of available prognostic tools. Discussion: The results of this study underline the significance of repeated molecular testing in patients with PV and ET and indicate the need for further research within this field to better understand the disease and improve available prognostic tools.

Anagrelide in essential thrombocythemia: Efficacy and long-term consequences in young patient population.

According to the current treatment recommendations, anagrelide, an oral antiplatelet agent, is recommended as a second-line therapy for patients with high-risk essential thrombocythemia experiencing intolerance or refractoriness to first-line approach, such as hydroxyurea or pegylated interferon alpha-2a. If there is a need for introduction of cytoreductive treatment in young patients with a perspective of lifelong exposure, both the efficacy and long-term outcomes should be known. We present the analysis of 48 young patients, diagnosed with essential thrombocythemia below the age of 60, who were exposed to anagrelide treatment for over 10 years. Our observations show that the highest proportion of complete remissions without adverse events and disease progression is seen in the JAK2-mutated patients. By evaluating the changes in hemoglobin concentration and serum erythropoietin throughout the study, we were able to reveal the development of progressive anemia, resulting from diminished susceptibility to erythropoietin and unrelated to bone marrow fibrosis, in patients harboring CALR mutation. Additionally, occurrence of new bone marrow fibrosis was confirmed in seven JAK2-unmutated patients at the end of the study. In summary, in young patient population, we recommend limiting the use of anagrelide to JAK2-mutated subgroup, reducing exposure time and underline the importance of periodic monitoring for the presence of bone marrow fibrosis.

Secondary chronic myeloid leukemia in a patient with CALR and ASXL1-mutated primary myelofibrosis.

Development of secondary CML has only been casually described, with few reports attempting to analyze and explain the mechanisms behind this phenomenon. Reported cases vary with regard to presumed pathogenesis and clinical characteristics, but similarities can be observed. This report presents the case of a patient diagnosed with CALR and ASXL1-mutated primary myelofibrosis who developed CML 13 years after the initial diagnosis. In contrast with previously reported cases, this patient did not have JAK2 or ABL1 gene mutations, and also exhibited primary resistance to tyrosine kinase inhibitor (TKI) treatment. Here, we analyze the molecular evolution of CML and describe successful treatment with concomitant therapy including a TKI and JAK inhibitor. This report aims to deepen clinical experience and further broaden knowledge about chronic myeloproliferative neoplasms.

Late polycythemic transformation in JAK2-mutated essential thrombocythemia patients-characteristics along with a validation of 2016 WHO criteria.

INTRODUCTION AND OBJECTIVES: The most common mutation within the spectrum of myeloproliferative neoplasms (MPNs) is a mutation in Janus kinase 2 gene (JAK2V617F). It has been observed that, during a course of disease, transformation from JAK2-mutated essential thrombocythemia (ET) to overt polycythemia vera (PV) can occur. Primary objective of this study was to show the incidence of mentioned phenomenon. METHODS: In this study, we analyzed data of 136 patients diagnosed with JAK2-positive ET observed for a median time of 9 years. We examined blood count of each patient at the time of diagnosis and confronted it with 2008 and 2016 WHO criteria for PV and mPV. Additionally, we analyzed JAK2V617F allele burden in two separate time points among selected cases. RESULTS: Confrontation with new criteria resulted in change of diagnosis to PV and mPV in 10% and 9% cases, respectively. Within remaining patients, 14 showed increasing hemoglobin concentration over several months during late course of disease, resulting in change of diagnosis to overt PV. We did not find suggested increase in JAK2 allele burden among transforming patients. CONCLUSIONS: Phenotype transformation to polycythemia was proven to be possible within the group of JAK2-mutated ET; however, cause of this effect remains uncertain.