Annual Clinical Updates in Hematological Malignancies: A Continuing Medical Education Series: Polycythemia vera and essential thrombocythemia: 2011 update on diagnosis, risk‐stratification, and management

Abstract

Disease overview: Polycythemia vera (PV) and essential thrombocythemia (ET) are myeloproliferative neoplasms primarily characterized by erythrocytosis and thrombocytosis, respectively. Other disease features include leukocytosis, splenomegaly, thrombohemorrhagic complications, vasomotor disturbances, pruritus, and a small risk of disease progression into acute leukemia or myelofibrosis. Diagnosis: Diagnosis is based on JAK2 mutation status (PV and ET), serum erythropoietin (Epo) level (PV), and bone marrow histopathology (ET). The presence of a JAK2 mutation and subnormal serum Epo level confirm a diagnosis of PV. Differential diagnosis in ET should include chronic myelogenous leukemia and prefibrotic myelofibrosis. Risk stratification: Current risk stratification in PV and ET is designed to estimate the likelihood of thrombotic complications: high‐risk‐age >60 years or presence of thrombosis history; low‐risk‐absence of both of these two risk factors. Presence of extreme thrombocytosis (platelet count >1,000 × 109/L) might be associated with acquired von Willebrand syndrome (AvWS) and, therefore, risk of bleeding. Risk factors for shortened survival in both PV and ET include age >60 years, leukocytosis, history of thrombosis, and anemia. Risk‐adapted therapy: Survival is near‐normal in ET and reasonably long in PV. The 10‐year risk of leukemic/fibrotic transformation is <1%/1% in ET and <5%/10% in PV. In contrast, the risk of thrombosis exceeds 20%. The main goal of therapy is therefore to prevent thrombohemorrhagic complications and this is effectively and safely accomplished by the use of low‐dose aspirin (PV and ET), phlebotomy (PV), and hydroxyurea (high risk PV and ET). Treatment with busulfan or interferon‐α is usually effective in hydroxyurea failures. Am. J. Hematol. 86:293–301, 2011. © 2011 Wiley‐Liss, Inc.

Assessment and prognostic value of the European LeukemiaNet criteria for clinicohematologic response, resistance, and intolerance to hydroxyurea in polycythemia vera

“…Hydroxyurea (HU) is the cytoreductive agent of choice for patients with polycythemia vera (PV) at high risk of developing thrombotic complications, [1][2][3][4] and it is also useful in controlling PV-related symptoms, splenomegaly, leukocytosis, marked thrombocytosis, and the hematocrit in patients with high need or poor tolerance to phlebotomy. [1][2][3][4][5] The bulk of the available evidence shows that HU bears a low leukemogenic potential.…”

“…[1][2][3][4][5] The bulk of the available evidence shows that HU bears a low leukemogenic potential. Besides, side effects of HU are infrequent and usually occur with high doses of the drug.…”

JAK inhibitors for myeloproliferative neoplasms: clarifying facts from myths

“…6 The safety and nonleukemogenicity of hydroxyurea, in this context, have repeatedly been highlighted by large retrospective studies, [7][8][9] and there is no controlled evidence to the contrary. 10 Second-line cytoreductive drugs in PV and ET, for patients who are either resistant or intolerant to hydroxyurea, include interferon IFN-␣, busulfan, and anagrelide. 11 There is no hard evidence to implicate any one of these 3 drugs as being leukemogenic, [12][13][14] whereas the data in this regard are significant enough to discourage the use of chlorambucil, 15 P32, 16 or pipobroman.…”

Polycythemia Vera Associated with IgA Nephropathy: A Case Report

“…Hastamızada flebotomi uygulandık. PV tedavisinde flebotomi yanısıra mylelosupresif ilaçlardan hidroksiüre, ɑ-interferon kullanılabilmektedir (11). Tromboembolik komplikasyonlar ve hastalığın miyelofibroz veya akut lösemiye ilerlemesi PV'nin en önemli morbidite ve mortalite nedenidir (12).…”

“…PV hastalarında proflaktik düşük doz aspirin (100mg/gün) kullanımı tromboz ve kardiyovasküler ölümleri azaltmaktadır. PV hastaları; tromboza yatkınlığı artıran doğum kontrol hapları, sigara ve hormon yerine koyma tedavisinden kaçınmalıdırlar (1,11,12). Hastamızda da oral kontraseptif kullanımının sagittal sinüs trombozu oluşumunu tetiklediğini düşündük.…”