EPID-10. VENOUS THROMBOEMBOLIC EVENTS IN GLIOBLASTOMA PATIENTS: AN EPIDEMIOLOGICAL VIEW

Abstract

Abstract BACKGROUND Venous thromboembolic events (VTE) are a common complication in cancer patients. Anticoagulant use is the appropriate treatment for acute VTE in cancer, although assumed to be associated with increased risk for bleeding. The population-based relationship of VTE and anticoagulant therapy to survival in glioblastoma patients remains unclear. METHODS Frequency, risk factors, treatment and complications of VTE were assessed in a glioblastoma cohort in the Canton of Zurich, Switzerland (2010 to 2014). Survival data were retrospectively analyzed using the log rank test. RESULTS 248 glioblastoma patients with known isocitrate dehydrogenase (IDH) wildtype status were identified in a 5-year time-frame. Median overall survival (OS) was 12.8 months (95% CI 11.0–14.6), with a median follow up of 60.7 months (95% CI 51.4–70.0). VTE were diagnosed in 35 patients (14.4%; 5 out of 248 patients with no follow-up data on VTE). Median time from diagnosis to VTE was 2.23 months (95% CI 0.6–3.9); 3 patients (8.6%) had a history of VTE. Most patients were on steroids at time of diagnosis of VTE (68.6%), and a Karnofsky Performance Score of less than 70% was documented in 21 patients (60%). Most patients with VTE (88.6%) received therapeutic anticoagulation. Complications, resulting in the cessation of therapeutic anticoagulation, occurred in 11 patients (35.5%), mainly (9 patients, 81.8%) due to intracranial hemorrhage. OS did not differ between patients diagnosed with VTE and those without VTE (p=0.103). Tumor progression was the major cause of death (91.3%); 1.4% of patients died from VTE; 1.9% of the patients suffered unexpected sudden death. CONCLUSION Although VTE were identified in 14.4% of glioblastoma patients, VTE were not the major reason for death. These data do not support the implementation of primary thromboprophylaxis in glioblastoma patients. Prospective clinical trials are needed to examine the association of anticoagulant use with survival in glioblastoma patients.