Essential thrombocythaemia

Essential thrombocythaemia is a chronic myeloproliferative neoplasm (MPN) associated with an increase in number and size of circulating platelets.

Clinical presentation includes vasomotor symptoms and complications from thrombosis and bleeding. Approximately 40% to 50% of patients are asymptomatic at diagnosis, and thrombocytosis is an incidental finding on routine blood testing.

There are no pathognomonic features and it is a diagnosis of exclusion.

Patients can be stratified into four risk groups to help guide treatment: very low-risk, low-risk, intermediate-risk, and high-risk.

Treatment approach should be individualised and may include lifestyle modification and observation, antiplatelet and anticoagulant therapy, and cytoreductive therapy.

Hydroxycarbamide is the preferred cytoreductive agent in most patients. Interferon, busulfan, and anagrelide are alternative treatments.

Life expectancy is reported to be modestly reduced compared with that of the general population. Patients require life-long blood count monitoring.

Essential thrombocythaemia (also known as primary thrombocythaemia) is a chronic myeloproliferative neoplasm. It is characterised by proliferation of abnormal megakaryocytes in the bone marrow, resulting in an increase in number and size of circulating platelets.