Abstract
Purpose of Review
Thrombocytosis is common to all myeloproliferative neoplasms (MPN), including essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis. Despite the traditionally held belief amongst many clinicians that thrombocytosis correlates with thrombosis risk, there is little evidence in the literature to support that claim. Herein we critically analyze the literature to better understand the relationship between thrombocytosis and risk of thrombosis in MPN.
Recent Findings
Both retrospective and prospective studies argue against associations between thrombocytosis and risk of thrombosis in patients with ET and PV. Rather, most studies suggest that the presence of extreme thrombocytosis is instead associated with an increased risk of hemorrhagic events, a paradoxical phenomenon with important clinical implications.
Summary
Thrombosis risk has a multifactorial set of etiologies in MPNs. While qualitative abnormalities of the platelets may contribute, associations between platelet quantity and thrombosis risk are weak in MPN patients.
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Galvez, C., Stein, B.L. Thrombocytosis and Thrombosis: Is There Really a Correlation?. Curr Hematol Malig Rep 15, 261–267 (2020). https://doi.org/10.1007/s11899-020-00588-z
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DOI: https://doi.org/10.1007/s11899-020-00588-z