RESUMO
The aim of the present paper was to evaluate the clinical features and risk of thrombotic events (TE) in patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF), depending on the molecular characteristics of disease. Clinical data and laboratory parameters were analyzed in 50 ET patients and 50 PMF ones who had been followed up at the Department for Standardization of Treatments, National Research Center for Hematology, Ministry of Health of the Russian Federation, from February 2015 to September 2016. The patients with ET and those with PMF were found to have a high risk of TE. The risk for TE in the patients with ET is higher (24% in the entire group) than in those with PMF (14% in the study group). In ET, there is a high thrombosis risk in the detection of JAK2 and CALR gene mutations as compared with triple-negative cases. The PMF patients with JAK2 V617F mutations are at high risk for TE compared to those who are CALR mutation carriers and in triple-negative cases. There was no significant association of TE with high thrombocytosis. A factor, such as age, was found to be of no negative prognostic value in the patients with PMF.
Assuntos
Calreticulina/genética , Janus Quinase 2/genética , Mielofibrose Primária , Receptores de Trombopoetina/genética , Trombocitemia Essencial , Trombose , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Mutação , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/epidemiologia , Mielofibrose Primária/genética , Medição de Risco/métodos , Federação Russa , Estatística como Assunto , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/epidemiologia , Trombocitemia Essencial/genética , Trombose/epidemiologia , Trombose/etiologia , Trombose/genéticaRESUMO
AIM: To evaluate the efficiency of interferon (IFN) therapy in patients with essential thrombocythemia (ET) and polycythemia vera (PV). SUBJECTS AND METHODS: A total of 61 patients (41 with ET and 20 with PV) were examined. Prior to study enrolment, 44 (72%) patients with ET or PV received one or other therapy (aspirin was not taken into account). The mean Jak2V617F mutant allele at baseline was 23% (6-54%) in the patients with ET and 40% (11-88%) in those with PV. The median time from diagnosis to enrollment was 49 months. RESULTS: The paper presents the clinical and molecular findings of long-term INF-α therapy in patients with ET or PV. The median follow-up was 52 months. Recombinant IFN-α2 showed its ability to induce complete hematologic remission (ET (76%), PV (70%)) and a complete molecular response. 22 (69%) out of 32 patients were noted to have a smaller number of cells with the Jak2V617F mutation. In the patients with PV and in those with ET, the relative reduction in the proportion of cells with the Jak2V617F mutant gene averaged 85% and 56% of the baseline values, respectively. There was a reduction in the proportion of cells expressing the Jak2V617F mutation in both the ET (from 12 to 2.2%; p=0.001) and PV (from 32.7% to 3.2%) groups (Ñ=0.001). Ten (31%) patients achieved a deep molecular remission (≤2% Jak2V617F allele); among them, 5 patients were not found to have Jak2V617F mutation. The obtained molecular response remained in 7 of the 10 patients untreated for 11 to 86 months. The long-term treatment with IFN-α led to normalization of the morphological pattern of bone marrow in 5 of the 7 PV or ET patients. CONCLUSION: Significant molecular remissions achieved by therapy with recombinant interferon-α2 confirm the appropriateness of this treatment option in in the majority of patients with ET or PV.