Modern Approaches to Diagnosis and Treatment of Essential Thrombocythemia: Literature Review and Own Experience

Objective. The aim of our study was to present literature data and own experience about epidemiology, terminology, etiology and pathogenesis of еssential thrombocythemia.

Methods. Molecular and genetic aspects of the disease pathogenesis and its clinical manifestations are described. The article dwells on issues related to diagnostic criteria, differential diagnosis and classification of essential thrombocythemia. Results of molecular genetic and cytogenetic studies, major causes of thrombotic complications, and methods of their prevention and treatment are presented. Treatment options and monitoring, as well as evaluation of the treatment effectiveness get considerable coverage. Literature review and analysis of diagnostic and treatment results of 218 essential thrombocythemia patients are presented: of them 161 were females, 57 were males, the gender ratio was 2.8:1, and the median age was 57.2 (varied from 18.3 to 89.3 years). Chromosomal aberrations were found in 7 (9.3 %) of 65 patients who had undergone cytogenetic testing. A JAK2V617F mutation was identified in 79 (58.1 %) of 136 patients, and a MPL gene mutation in 1 (2.3 %) of 44 patients.

Results. The overall 10 year survival rate of 218 essential thrombocythemia patients was 83.9 %. Progression in the form of secondary post-essential thrombocythemia myelofibrosis was registered in 13 (6 %) patients. The treatment included hydroxyurea (n = 132), interferons-a (n = 37), anagrelide (n = 10), and acetylsalicylic acid (n = 54). The mortality rate over the whole 10 year observation period was 16.1 % (n = 35).

Conclusion. Timely and early diagnosis of essential thrombocythemia, thrombosis risk-adapted management and adequate follow-up with platelet count monitoring are cornerstones for preservation of patient’s duration and quality of life.

• K.M. Abdulkadyrov Russian Scientific Research Institute of Hematology and Transfusiology, 16 2-ya Sovetskaya str., Saint Petersburg, Russian Federation, 191024 ; ФГБУ «Российский научно-исследовательский институт гематологии и трансфузиологии Федерального медико-биологического агентства», ул. 2-я Советская, д. 16, Санкт-Петербург, Российская Федерация, 191024
• Vasilii Anatol’evich Shuvaev Russian Scientific Research Institute of Hematology and Transfusiology, 16 2-ya Sovetskaya str., Saint Petersburg, Russian Federation, 191024 ; ФГБУ «Российский научно-исследовательский институт гематологии и трансфузиологии Федерального медико-биологического агентства», ул. 2-я Советская, д. 16, Санкт-Петербург, Российская Федерация, 191024
• I.S. Martynkevich Russian Scientific Research Institute of Hematology and Transfusiology, 16 2-ya Sovetskaya str., Saint Petersburg, Russian Federation, 191024 ; ФГБУ «Российский научно-исследовательский институт гематологии и трансфузиологии Федерального медико-биологического агентства», ул. 2-я Советская, д. 16, Санкт-Петербург, Российская Федерация, 191024

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