Dural sinus thrombosis owing to polycythaemia vera in a 12-year-old girl

Cerebral Venous Thrombosis in Hematological Malignancy: Balancing the Risks

BACKGROUND AND AIM

The coexistence of cerebral venous thrombosis (CVT) and hematological neoplasms is rare. Currently available therapeutic options raise problems concerning the balance of thrombotic and hemorrhagic risks. Our purpose is to characterize a series of cases of CVT and concomitant hematological malignancy, focusing on predisposing factors and treatment strategies.

METHODS

We performed a descriptive retrospective analysis of the cases of CVT and hematological neoplasms diagnosed in a tertiary center from 2006 to 2015.

RESULTS

From the 111 CVT cases diagnosed, only 7 coexisted with hematological malignancy (lymphoma, leukemia, multiple myeloma, and myelodysplastic syndromes). These included 4 women; median age was 44 years old. Median follow-up time was 72 days. The hematological condition was already known in 5 cases. Besides malignancy, we identified other prothrombotic conditions in all cases. Several anticoagulant strategies were used during the acute phase, after which 5 patients remained on warfarin indefinitely. One patient died due to cerebral hemorrhage during the acute phase. In the remaining 6 patients, there was no recurrence of CVT or other complications of anticoagulation.

CONCLUSIONS

Although these results reiterate the role of hematological malignancy as predisposing factor to CVT, in all cases other factors contributed to CVT etiology, potentiating the risk. We report 1 death directly attributable to a fatal hemorrhagic complication of anticoagulation, evidencing the delicate balance of thrombotic and hemorrhagic risk. Nevertheless, most patients benefited of long-term anticoagulation, which proved a reasonable option. A multidisciplinary approach is paramount in making decisions regarding the time and type of anticoagulation.

Myeloproliferative Neoplasms in Children and Adolescents and Thrombosis at Unusual Sites: The Role of Driver Mutations

Myeloproliferative neoplasms (MPNs) in childhood and adolescence are rare and seldom complicated by thrombosis. We describe 3 cases of thrombosis at unusual sites in young patients with MPNs. In the pediatric MPN population, unlike in adult MPNs, a clonal mutation is identifiable in only a minority of cases (22% to 26%). All 3 of these individuals had JAK2 mutations driving the disease process. A literature search identified 19 cases of MPN-associated thrombosis in children. Seventeen of the 19 children (89.5%) had a driver mutation. These cases suggest that identifiable driver mutations may confer an increased thrombotic risk in children with MPNs.

Characteristics and outcomes of patients with essential thrombocythemia or polycythemia vera diagnosed before 20 years of age: a systematic review

Although it is well known that myeloproliferative neoplasms occur in younger patients, few large cohorts of such patients have been reported. Thus, our knowledge about circumstances of diagnosis, outcome and treatment is limited, especially for children and young adults. We therefore performed a systematic review of cases, published since 2005, concerning patients aged below 20 years at the time of diagnosis of essential thrombocythemia or polycythemia vera. We identified 396 cases of essential thrombocythemia and 75 of polycythemia vera. The median age at diagnosis was 9.3 and 12 years, respectively, and females constituted 57.6% and 45% of the groups, respectively. Half of the patients were asymptomatic at diagnosis. The proportion of so-called triple negativity was high: 57% in essential thrombocythemia and 73% in polycythemia vera. The incidence of thrombosis during the follow-up was 9.3% in patients with polycythemia vera and less, 3.8%, in those with essential thrombocythemia. Venous events were predominant (84.2%), with hemorrhagic episodes being rarer (<5%). The risk of evolution also seemed low (2% to myelofibrosis and no reports of acute leukemia), but the median follow-up was only 50 months. Survival curves were not available. Half of the patients received an antithrombotic drug and 40.5% received a cytoreductive drug. All data should be analyzed with care because of the proportion of missing data (10.7% to 74.7%). This review highlights interesting points concerning this population of young patients with myeloproliferative neoplasms, including that such patients were identified as negative for all common driver mutations, but also shows the need for larger contemporary cohorts with longer follow-up to assess the true prognosis of these patients.