Clinical significance of V617F mutation of the JAK2 gene in patients with chronic myeloproliferative disorders

Abstract

Objective: To determine the prevalence of JAK2 V617F mutation and its clinical correlation in patients with chronic myeloproliferative disorders (CMD): polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF).

Materials and methods: Detection of JAK2 V617F mutation by allele specific-PCR.

Results: One hundred and three patients with CMD were included in the study. JAK2 V617F distribution was PV 40/45 (89%), ET 30/43 (69%), and IMF 7/15 (47%). In PV and ET patients only, 18 had thrombosis at diagnosis and 12 during follow-up (these were microvascular: 11, venous: 7 and arterial: 12); of these 28/70 (40%) were JAK2pos versus 2/18 (11%) JAK2neg; P=0·02. In a median of 4 years, two patients with PV JAK2pos evolved to myelofibrosis and one patient with PV presented in leukemic transformation (JAK2pos before and after transformation); six patients died: four patients with IMF and two patients with PV.

Conclusions: We found an association between JAK2 V617F and thrombotic events in patients with PV and ET.

Keywords:

• JAK2
• MYELOPROLIFERATIVE DISORDERS
• THROMBOSIS
• SURVIVAL
• ACUTE LEUKAEMIA