Splanchnic vein thrombosis in myeloproliferative neoplasms: risk factors for recurrences in a cohort of 181 patients

Abstract

We retrospectively studied 181 patients with polycythaemia vera (n=67), essential thrombocythaemia (n=67) or primary myelofibrosis (n=47), who presented a first episode of splanchnic vein thrombosis (SVT). Budd–Chiari syndrome (BCS) and portal vein thrombosis were diagnosed in 31 (17.1%) and 109 (60.3%) patients, respectively; isolated thrombosis of the mesenteric or splenic veins was detected in 18 and 23 cases, respectively. After this index event, the patients were followed for 735 patient years (pt-years) and experienced 31 recurrences corresponding to an incidence rate of 4.2 per 100 pt-years. Factors associated with a significantly higher risk of recurrence were BCS (hazard ratio (HR): 3.03), history of previous thrombosis (HR: 3.62), splenomegaly (HR: 2.66) and leukocytosis (HR: 2.8). Vitamin K-antagonists (VKA) were prescribed in 85% of patients and the recurrence rate was 3.9 per 100 pt-years, whereas in the small fraction (15%) not receiving VKA more recurrences (7.2 per 100 pt-years) were reported. Intracranial and extracranial major bleeding was recorded mainly in patients on VKA and the corresponding rate was 2.0 per 100 pt-years. In conclusion, despite anticoagulation treatment, the recurrence rate after SVT in myeloproliferative neoplasms is high and suggests the exploration of new avenues of secondary prophylaxis with new antithrombotic drugs and JAK-2 inhibitors.

Splanchnic vein thromboses associated with myeloproliferative neoplasms: An international, retrospective study on 518 cases

“…Clinical features and outcome of MPN patients with SVT (MPN‐SVT) have been reported in a number of studies, either monocentric series of consecutive cases or larger cooperative cohorts, with overall consistent findings regarding demographics and phenotype. In fact, SVT are known to occur more commonly in younger MPN patients, especially women; PV is the most frequent diagnosis; concomitant thrombophilia is reported in nearly a third of cases.…”

“…However, recognition of an underlying MPN can be challenging since portal hypertension, iron deficiency and/or hepatic ischemia may influence hematological parameters or inappropriately increase endogenous erythropoietin . JAK2 V617F mutation is a reliable marker of underlying MPN, being found in the vast majority (76%‐93%) of SVT in patients with overt MPN, as well as in 25%‐43% of unselected SVT . As such, JAK2 V617F screening is recommended for any SVT patient, to identify those MPN (15%‐17%) that would otherwise be missed .…”

A guideline for the management of specific situations in polycythaemia vera and secondary erythrocytosis

“…Cytoreduction was used in 40–70% patients across registries and did not uniformly influence recurrence risk. However, abnormally high blood counts due to inadequate cytoreduction were present in over half the patients with recurrent thrombosis (De Stefano et al , 2016b) indicating the need for rigorous clinical monitoring of patients on cytoreduction. Venesection alone is not appropriate to treat PV and cytoreduction should be undertaken in the presence of SVT.…”

“…On this basis, PVrelated SVT is an indication for long-term anticoagulation. Several prospective and retrospective registry studies conclude that long-term anticoagulation reduces recurrence risk at splanchnic and other sites with an acceptable level of bleeding complications (Amitrano et al, 2007;Ageno et al, 2015;De Stefano et al, 2016b). Recurrence in the arterial circulation has been observed in patients not on anti-platelet agents (Hoekstra et al, 2011;De Stefano et al, 2016b).…”

Association between myelofibrosis and thromboembolism: A population‐based retrospective cohort study

“…Our study shows that history of previous venous thromboembolism and atrial fibrillation are the only independent risk factors for the increased risk of venous thromboembolism in patients with myelofibrosis. In this regard, the role of previous venous thrombosis as risk factor for future venous thromboembolism after diagnosis of MF has been described already, but the role atrial fibrillation in this specific group of patients hasn't yet been evaluated. However, atrial fibrillation was found to be associated with increased risk of venous thromboembolism in the general population .…”