Is the Chronic Myeloproliferative Disease Prognosis Really Different in Geriatric Patients?

Introduction

Chronic myeloproliferative neoplasms (MPN) are clonal diseases of multipotent hematopoietic progenitor cells. Since the discovery of the JAK2V617F mutation in the pathogenesis of MPN in 2005, many studies have been conducted to evaluate the clinico-hematological importance of this mutation. High-risk patients are defined as those who are older age and have had a thrombotic attack. In this study, our aim was to identify the clinico-hematological and prognostic factors of MPN in geriatric patients compared with a young adult group based on JAK2V617F status.

Method

We retrospectively evaluated 140 patients total who had been diagnosed based on the WHO MPN diagnosis criteria, between 2007 and 2014 in the Department of Hematology at Ankara University. The frequencies of the JAK2V617F mutation, thrombosis, hemorrhage, treatment side effects, fibrosis and leukemic transformation between the groups were evaluated by the Pearson chi-square test, while the thrombosis risk due to hematologic parameters in the geriatric group was evaluated by the Mann-Whitney Test and T-test.

Results

Of the 140 MPN patients, 57 (41%) were diagnosed with polycythemia vera (PV), 66 (47%) with essential thrombocythemia (ET), and 17 (12%) with primary myelofibrosis (PMF). Fifty-two patients (37%) were in the geriatric age group, while 88 patients (62%) were defined as young adults. Twenty-two (42%) of the patients in the geriatric group were diagnosed with PV, 26 (50%) with ET, and 4 (%8) with PMF; similar numbers were observed in the young adult group (P >.05). In the young adult group, 31 patients (35%) were female, while in the geriatric group, 33 patients (64%) were female; this difference is statistically significant (P =.001). JAK2V617F mutation positivity was significantly higher in the geriatric group (35/52 (67%) vs 37/88 (42%) in the young adult group; (P =.004). In the geriatric group, the patients with PV were most frequently treated with hydroxyurea (HU) and acetylsalicylic acid (ASA), while in the young adult group, phlebotomy and ASA were the most common treatments (60% vs 57%, respectively). The preferred treatments for patients with ET were HU and ASA in both groups (54% vs 48%). Patients with PMF in the young adult group were most commonly treated with thalidomide and steroids (50%), while most of the geriatric patients received no treatment (38%). No significant difference was detected between the groups due to treatment side effects (P >.05). In both groups, the most frequent second line treatments used in both PV and ET were thromboreductin and ASA, while the PMF patients in the young adult group also underwent allogeneic stem cell transplantation. The thrombosis frequency during follow-up was similar between groups (25% vs 13%, P=.067), even in JAK2V617F mutation-positive patients (26% vs 19%, P >.05). Thrombosis in the central nervous system was most commonly detected in the geriatric group (34%), while coronary artery thrombosis was most common in young adults (44%). There was no significant relationship between leukocyte, hemoglobin and platelet counts and the frequency of thrombosis in the geriatric group (P >.05). Ten geriatric patients (19%) and 9 young adult patients (11%) had severe hemorrhage, and this difference was not statistically significant between the groups (P >.05). One patient in each group had leukemic transformation. The increased fibrosis frequency in bone marrow morphology was similar between the groups (P >.05). Two of the 9 patients with increased fibrosis in the young adult group and 1 patient with leukemic transformation in the geriatric group died during follow-up.

Conclusion

In this study, no significant differences were detected in treatment side effects, thrombosis risk, severe hemorrhage, leukemic transformation or increased bone marrow fibrosis between the geriatric and young adult groups, even though the JAK2V617F mutation frequency was significantly higher in the geriatric group. Early and effective treatment modalities used in geriatric patients will improve survival and prevent complications.