Coagulation Disorders in Philadelphia Chromosome-negative Myeloproliferative Neoplasms-A Guide for Specialists in...

Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) are acquired clonal disorders of hematopoiesis that typically cause thromboembolic and hemorrhagic complications. These include an increased risk of both arterial and venous thromboembolic events as well as a heightened bleeding tendency. Venous thromboembolic events frequently manifest at atypical sites and characteristically present as splanchnic vein thrombosis. A common cause of the elevated bleeding risk is acquired von Willebrand syndrome. Clinical indicators of an underlying MPN include thromboembolic events of unclear etiology or occurring at atypical sites, as well as acquired cutaneous or mucocutaneous bleeding tendencies. A hallmark of MPN in peripheral blood counts is hyperproliferation. Further diagnostic evaluation includes testing for the three major driver mutations (JAK2, CALR, MPL) and bone marrow biopsy. Management of thromboembolic event requires cytoreductive therapy and, depending on the site of thrombosis, antiplatelet therapy, and/or anticoagulation.

Our review provides an overview of essential thrombocythemia, polycythemia vera, and primary myelofibrosis, as well as the hemostatic disorders associated with these conditions, focusing on diagnostic approaches and the prophylaxis and management of thromboembolic and bleeding complications.