Polycythemia Vera: Literature Review and Own Data

MYELOID TUMORS , ,

I.N. Subortseva, T.I. Kolosheinova, E.I. Pustovaya, E.K. Egorova, A.M. Kovrigina, Yu.V. Pliskunova, T.V. Makarik, A.O. Abdullaev, A.L. Melikyan

Hematology Research Center under the Ministry of Health of the Russian Federation, 4а Novyi Zykovskii pr-d, Moscow, Russian Federation, 125167

For correspondence: Irina Nikolaevna Subortseva, PhD, 4а Novyi Zykovskii pr-d, Moscow, Russian Federation, 125167; Tel.: +7(495)612-44-72; e-mail: soubortseva@yandex.ru

For citation: Subortseva IN, Kolosheinova TI, Pustovaya EI, et al. Polycythemia Vera: Literature Review and Own Data. Clinical oncohematology. 2015;8(4):397–412 (In Russ).

DOI: 10.21320/2500-2139-2015-8-4-397-412

ABSTRACT

Background & Aims. Polycythemia vera (PV) refers to a group of classic Ph-negative myeloproliferative neoplasms characterized by panmyelosis, pancytosis, high risk of thrombotic and hemorrhagic complications, poor quality of life due to symptoms of tumor proliferation. Low-dose acetylsalicylic acid and phlebotomy/erythrocytapheresis are recommended for patients at low risk of complications, while the cytoreductive therapy (hydroxyurea or interferon alpha) is recommended for patients at high risk of thrombotic and hemorrhagic complications. At present, much attention is paid to the problems of diagnosis and treatment PV.

Methods. The article presents a brief description of the condition, a review of modern methods of treatment, results of observation over 100 PV patients who have been treated in the outpatient department of the Hematology Research Center. The observation period ranged from 6 to 262 months (median follow-up is 14 months).

Results. Patients’ age ranged from 23 to 80 years (median 56 years); 67 % of them were women, and 33 % were men. PV was diagnosed according to 2008 WHO guidelines. JAK2V617F mutation was detected in 100 % of cases. Splenomegaly was found in 70 % of patients. Plethoric symptoms (such as facial and hand hyperemia, and scleral injection) were found in 65 % of patients. All patients complained of headaches and dizziness, and 25 % of patients complained of itching. All patients received symptomatic therapy, antiaggregants, medications improving microcirculation, or antihypoxants. Patients were treated according to clinical guidelines: 49 % of them received hydroxyurea, 14 % IFN a-2b, 14 % a combination therapy (hydroxyurea and phlebotomy or IFN a-2b and phlebotomy), and 23 % of patients phlebotomy alone. Response to treatment was evaluated according to 2009 European LeukemiaNet criteria. Among all patients, the frequency of complete remission was 48 %, the partial response rate was 41 %, and no effect was achieved in 11 % of patients regardless they received therapy or not. The therapy was changed, if the treatment had proved to be ineffective, or in case of intolerance or complications. Complete remission was not achieved after switching treatment from one method to another.

Conclusion. Treatment of PV is mainly symptomatic. The effectiveness of first line therapy (complete remission) ranged from 14.5 to 71 %. It is necessary to conduct clinical trials designed to evaluate the effectiveness and safety of new targeted therapies.

Keywords: myeloproliferative neoplasms, polycythemia vera, JAK2V617F, target therapy.

Received: June 30, 2015

Accepted: November 5, 2015

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