Stroke in essential thrombocythemia.

Background: Our aim was to assess the incidence and the special characteristics of stroke, as a severe complication of patients diagnosed with essential thrombocythemia (ET).

Methods: A retrospective analysis was carried out on 102 patients with ET enrolled and analyzed from the period between 1999 and 2012. Patients with one or more strokes were selected. The characteristics of stroke events, the medication, and the median platelet counts were revised.

Results: One or more stroke events were revealed in 11 cases (4 males and 7 females) with a median age of 67 years [range: 45-82 years]. The median platelet count at hematological diagnosis was 658×10(9)/L [range: 514-1157×10(9)/L], while during the time of stroke it was 450×10(9)/L [range: 320-885×10(9)/L]. The median follow-up of the patients with stroke was 60 months [range: 19-127 months]. At the time of the stroke, almost all the patients (8/11 cases, 73%) were already on anti-platelet therapy, alone or in combination with cytoreductive therapy (e.g. hydroxyurea). Brain imaging modalities in most cases demonstrated periventricular and/or subcortical and/or basal ganglia lacunes or confluent chronic white matter ischemic lesions in all cerebral arterial regions. Most patients (9/11; 82%) presented at least two serious conventional vascular risk factors, which may have influenced both the clinical course and the morphologic alterations. No correlation was found between the platelet count and the occurrence of stroke.

Conclusion: Our findings lead us to suppose that ET may be regarded as a risk factor for stroke (mainly of ischemic, small-vessel type), and the early diagnosis and the personalized management of the patient's global vascular risk in the treatment of ET may promote the prevention of further cerebrovascular events.