[Thrombosis in myeloproliferative neoplasms]

Among all types of myeloproliferative neoplasms (MPNs), polycythemia vera (PV) and essential thrombocythemia (ET) require careful management of both thrombosis and hemostasis. One recent concern associated with MPNs is the JAK2 mutation (V617F). This mutation is essential for MPN pathology, but it has also garnered attention for its association with thrombosis. Several studies have reported the mechanisms underlying the onset of thrombosis in both PV and ET and have also discussed the association between JAK2 mutations and thrombotic tendencies. Arterial thrombosis is a common clinical symptom that is associated with the diagnosis and course of both PV and ET. Particularly, cerebral infarction has been identified as the leading cause of death in patients with untreated PV. Notably, PV and ET are also associated with a high incidence of venous thromboembolism (VTE). The occurrence of this type of thrombosis at atypical sites, such as cerebral venous sinus thrombosis and splanchnic vein thrombosis (SVT), is not uncommon. Generally, patients with PV and ET have good life expectancy; their treatment essentially focuses on dealing with thrombosis and bleeding. Phlebotomy may be used for treating patients with PV; however, low-dose aspirin is used to prevent the onset of arterial thrombosis. For patients with a history of VTE, oral anticoagulants are commonly prescribed to prevent recurrence.