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Recommendations of Polish Adult Leukemia Group concerning diagnostics and treatment of polycythemia vera

Joanna Góra-Tybor1, Tomasz Sacha2, Maria Bieniaszewska3, Marta Sobas4, Krzysztof Lewandowski5, Patryk Sobieralski3, Olga Chyrko4, Aleksandra Gołos1

Abstract

Polycythemia vera (PV) belongs to a group of myeloproliferative neoplasms (MPN). The diagnosis of PV is based on the evaluation of complete blood count, bone marrow trephine biopsy samples, and molecular tests (confirmation of the JAK2 mutation). The main objectives of PV treatment include preventing thromboembolic complications, alleviating disease symptoms, and lowering the risk of transformation to myelofibrosis, acute myeloid leukemia and myelodysplastic syndrome. Taking into consideration the long-term course of PV, the choice of therapy should be based on an analysis of the risks resulting from the disease as well as from the adverse effects of the medication applied. In patients without risk factors (age < 60 years; no history of thrombosis), acetylsalicylic acid (ASA) and phlebotomy are recommended. Cytoreductive treatment is recommended in patients with poor tolerance of phlebotomy and with leukocytosis > 20 G/L, symptomatic progressive splenomegaly, significant thrombocytosis, persistent general symptoms of PV, and also in patients with significant cardiovascular risk. The therapy of choice in these patients is interferon α (IFNα). In a high-risk group of patients, (age ≥60 years and/or a history of thrombosis), treatment with ASA and phlebotomy should be accompanied by cytoreduction: hydroxyurea (HU) or, in the case of HU resistance/ intolerance, ruxolitinib (RUX) or IFNα. This paper discusses some aspects of the risk evaluation and summarizes the effectiveness of the available therapies, and also presents diagnostic and therapeutic recommendations for PV.

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