PB2217 EPIDEMIOLOGICAL, CLINICAL, MOLECULAR AND GENETIC CHARACTERISTICS OF PRIMARY MYELOFIBROSIS IN THE RUSSIAN FEDERATION
Authors: A. Melikyan, I. Subortseva, D. Baryshniikova, E. Volodicheva, E. Gilyazitdinova, N. Glonina, G. Dimov, M. Ivanova, K. Kaplanov, A. Kaplina, E. Kirillova, M. Kiseleva, T. Klitochenko, T. Koloshejnova, E. Komarceva, S. Kulikov, E. Lomaia, M. Mihalev, O. Senderova, M. Fominykh, A. Hazieva, Y. CHabaeva, Y. CHernyh, K. Shashkina, V. SHuvaev
Journal: HemaSphere (2019)

Background: To date studies have not been conducted to assess the epidemiological characteristics of Ph‐negative myeloproliferative neoplasms, in particular primary myelofibrosis (PMF) in the Russia. Aims: Creation of the Russian registry of primary myelofibrosis to assess the epidemiological clinical molecular characteristics of the PMF. Methods: In 2017 initiated a multicenter prospective observational cohort study involving 14 research centers from 11 regions of Russia. The study included 188 patients: 177 (94%) with PMF, 10 patients with post‐PV MF and 1 patient with post‐ET MF. Men: women ratio – 1: 1,3. Results: The incidence of PMF in various regions of the Russia ranges from 0.05 to 2.12 per 100000 (Table 1, 2). Among patients with PMF, post‐PV MF and post‐ET MF, 44% (83) are patients in the age group 60‐74 years, 28% (53) in the age group 45‐59 years, 17% (32) ‐ patients aged 18‐44 years, 11% (20) ‐ in the age group 75‐90 years. Constitutional symptoms were recorded in the majority of patients: fatigue ‐ 78% (147), lethargy ‐ 65 (122), headache ‐ 40% (75), discomfort in the stomach ‐ 38% (72), discomfort in the left hypochondrium ‐ 38% (71), night sweats ‐ 32% (61), feeling of early satiety ‐ 30% (56), weight loss ‐ 26% (48), bone pain ‐ 23% (43), sweating ‐ 15% (28), skin itching ‐ 11% (20), fever ‐ 6% (12). No symptoms mediated by the disease ‐ 5% (10). Splenomegaly at the time of diagnosis was recorded in 76% (143 patients). Molecular analysis performed at 94% of patients (176): JAK V617F mutation detected in 122 patients, JAK2 exon12 ‐ 1, CALR ‐ 34, MPL ‐ 7, triple negative variant ‐ 13. Allelic burden of JAK2 V617F defined in 90 patients with PMF, median ‐ 34% (1 ‐ 100%). Data on allelic burden JAK2V617F was in 7 patients with post‐PV MF, the median was 57% (3 ‐ 88%). Histological examination of bone marrow performed by 91% (171 patients). Histochemical studies with an assessment of the degree of reticulin fibrosis ‐ 81% (153). Confirmation of the diagnosis according to the full set of criteria in patients with PMF registered in 54% of patients. The distribution of patients by risk groups in accordance with the IPSS prognostic scale: low ‐ 26%, intermediate‐1 ‐ 33%, intermediate‐1 ‐ 23%, high ‐ 18%. The first line of therapy: hydroxyurea ‐ 58%, ruxolitinib ‐ 14%, interferon‐alpha ‐ 10%, glucocorticosteroids ‐ 5%, erythropoietin 3%, anagrelide ‐ 1%, other therapy ‐ 9%. Blood transfusions performed in 70% of patients, thromboconcentrate transfusions ‐ 6%. Concomitant therapy is given to 63% (119 patients): acetylsalicylic acid ‐ 78, allopurinol ‐ 49, erythropoietin ‐ 11, clopidogrel ‐ 6, NSAID ‐ 3, sulodexide ‐ 3, tranexamic acid ‐ 1, etamzilat ‐ 1, other (dipyridamole, iron preparations, folic acid, vitamin B12) ‐ 30. The efficacy of therapy assessed for 52 patients: complete clinical and hematological remission ‐ 23% (12), partial clinical and hematological remission ‐ 48% (25), stabilization of the disease ‐ 29% (15). 5 deaths reported. The 2‐year overall survival rate was 97% (Figure 1). Summary/Conclusion: In general the registry of patients with PMF allows integrating information into a common system and obtaining information characterizing the population of patients with this disease in Russia. image