Cerebral venous sinus thrombosis in children with acute lymphoblastic leukemia carrying the MTHFR TT677 genotype and further prothrombotic risk factors

Background: The present study was designed to prospectively evaluate the ro le of prothrombotic risk factors in leukemic children treated according to the ALL-BFM 90/95 study protocols with respect to the onset of cerebral ven ous sinus thrombosis. Patients: 317 consecutive leukemic children aged 6 months to 18 years were enrolled in this study. 288 of the 317 patients were available for thrombos is-free survival analysis. Results: In 17 (5.9%) of these 288 patients cerebral venous sinus thrombosi s occurred. The overall event-free survival of thrombosis in the central ne rvous system in patients with at least one prothrombotic defect (n = 12) wa s significantly reduced compared with patients without a prothrombotic defe ct (p<0.0001). 15 patients showed acute Clinical symptoms at onset of cereb ral venous sinus thrombosis, two were asymptomatic. Three of the 17 patient s affected (17.6%) died directly associated with the thrombotic event durin g induction therapy, the remaining 14 patients did not show prolonged clini cal symptoms. Conclusions: Prothrombotic risk factors should be included in a screening p rogram in ALL children treated according to the BFM study protocols. Furthe r prospective studies are recommended to establish adequate prophylactic an ticoagulant treatment during ALL (BFM) polychemotherapy.