Multicenter Retrospective Analysis of Turkish Patients with Chronic Myeloproliferative Neoplasms

Chronic myeloproliferative neoplasms (CMPNs) that include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) are Philadelphia-negative malignancies characterized by a clonal proliferation of one or several lineages. The aim of this report was to determine the demographic features, disease characteristics, treatment strategies, and survival rates of patients with CMPNs in Turkey.

Across all of Turkey, 9 centers were enrolled in the study. We retrospectively evaluated 708 CMPN patients' results including 390 with ET, 213 with PV, and 105 with PMF.

The JAK2V617F mutation was found positive in 86% of patients with PV, in 51.5% of patients with ET, and in 50.4% of patients with PMF. Thrombosis and bleeding at diagnosis occurred in 20.6% and 7.5% of PV patients, 15.1% and 9% of ET patients, and 9.5% and 10.4% of PMF patients, respectively. Six hundred and eight patients (85.9%) received cytoreductive therapy. The most commonly used drug was hydroxyurea (89.6%). Leukemic and fibrotic transformations occurred at rates of 0.6% and 13.2%. The estimated overall survival in PV, ET, and PMF patients was 89.7%, 85%, and 82.5% at 10 years, respectively. There were no significant differences between survival in ET, PV, and PMF patients at 10 years.

Our patients' results are generally compatible with the literature findings, except for the relatively high survival rate in PMF patients. Hydroxyurea was the most commonly used cytoreductive therapy. Our study reflects the demographic features, patient characteristics, treatments, and survival rates of Turkish CMPN patients.