Study Examines Cerebral Venous Thrombosis in Patients With MPNs

In a case series published in the American Journal of Hematology, authors evaluated the relationship between myeloproliferative neoplasms (MPNs) and cerebral venous thrombosis (CVT). Patients with essential thrombocythemia appeared to have the highest incidence of CVT, but rates were generally low across all MPN subtypes, the researchers reported

“The recent association of [CVT] with COVID-19 vaccinations prompted the current retrospective review,” the authors noted.

The analysis included 74 patients with CVT (median age, 44 years; range, 15-85; female, 61%) that was associated with MPN who were treated between 1991 and 2021 at three centers: Mayo Clinic, Catholic University of Rome, and University of Florence.

Disease-specific frequencies were:

  • essential thrombocythemia: 1.3% (39/2,893)
  • polycythemia vera: 1.2% (21/1,811)
  • primary myelofibrosis: 0.2% (3/1,888)

The researchers observed that CVT occurred either prior to (n = 20, 27%), at (n = 32, 44%), or after (n = 22) MPN diagnosis.

Approximately three-quarters (72%) of patients presented with headaches. Transverse (51%), sagittal (43%), and sigmoid sinuses (35%) were involved, with central nervous system hemorrhage noted in 10 patients (14%), the authors added. Nearly all patients (91%) harbored JAK2V617F mutation. Nineteen patients (31%) had an underlying thrombophilic condition and 10 (14%) had a history of thrombosis.

Following CVT diagnosis, most patients were treated with systemic anticoagulation alone (n = 27) or in conjunction with aspirin (n = 24), followed by cytoreductive therapy (n = 14) or both (n = 9).

After a median follow-up of 5.1 years (range, 0.1-28.6), three patients (4%) experienced recurrent CVT. Recurrent arterial and venous thromboses and major hemorrhage were recorded in 11%, 9%, and 14% of patients, respectively.

On follow-up neurological assessment, nine patients had headaches, one had vision loss, and one had cognitive impairment.

“The current study lends clarity on MPN-associated CVT and highlights its close association with JAK2V617F, younger age, and female gender,” the authors concluded. “Clinical features that distinguish COVID vaccine-related from MPN-CVT include lower likelihood of concurrent venous thromboses and intracerebral hemorrhage with the latter; as a result, MPN-CVT was not fatal.”