Ph negative myeloproliferative neoplasms in Czech haematological centres – MIND analysis

Overview

Background: Our MIND database was initiated on May 1, 2013, with the primary objective of collecting data from patients with Ph negative myeloproliferative neoplasms (Ph-MPN) in Czech haematological centres. The principal aim was to analyse and compare our patient data with published data. Patients and Methods: A total of 641 valid Ph-MPN patients registered in MIND were analysed from 2013 to 2020. Epidemiology, dia­gnostics, therapy and prognosis were evaluated. Results: With a 35-month median follow-up, the most common dia­gnosis was polycythaemia vera- PV (34%) followed by primary myelofibrosis, PMF (31%) and essential thrombocythemia, ET (22%). At the time of dia­gnosis, patients suffered mostly from fatigue (52%), night sweats (32%), weakness (30%) and itching (27%). Splenomegaly occurred in more than half of PMF patients (54%). The JAK2 V617F mutation was present in 90% of PV, 65% of PMF and 62% of ET, respectively. The CALR mutation was found in 22% of ET and 16% of PMF, respectively. Cytogenetic abnormalities were significantly more frequently documented in both PMF and PV compared to ET (17 and 15 vs. 3% of examined patients, respectively; P ≤ 0.005). Thrombosis (22%) and bleeding (10%) were the most common complications at dia­gnosis with no significant difference in frequency among PV, ET, and PMF, respectively (P > 0.017). In PV, hydroxyurea was the most frequently used drug as both 1^st and 2^nd line treatment (72 and 65%, respectively). Anagrelide was used in both lines in ET (52 and 82%, respectively) and hydroxyurea was used as 1^st line treatment with ruxolitinib as 2^nd line treatment in PMF (70 and 30%, respectively). Leukemic transformation was detected in 3% of Ph-MPN and only in MF (10%). 17% of our patients died, most from PMF (53%). Median overall survival was not attained in ET, contrasting with the lowest median in secondary MF (2.5 years). In PMF, median overall survival was decreased by dotage, higher IPSS, and JAK2 V617F mutation presence. Conclusion: We have recognized a recurring definitive frequency of symptoms that exacerbate patient quality of life. A higher incidence of additional cytogenetic abnormalities was recorded more frequently with both PMF and PV compared to ET. During dia­gnosis, thrombotic and bleeding events were present with no significant difference in frequency among PV, ET, and PMF. Overall survival median was the longest in PV, compared to MF with the most frequent leukemic transformations and the lowest survival. In PMF, higher age, higher IPSS and JAK2 V617F presence were shown as factors shortening survival.