EPID-08. CLINICAL AND MOLECULAR DETERMINANTS OF BLEEDING-RELATED ADVERSE OUTCOMES IN HIGH-GRADE GLIOMA

Abstract

Abstract Cancer is an independent risk factor for the development of venous thromboembolism (VTE) however patients with high-grade glioma (HGG) including glioblastoma (GBM) are at a particularly high risk of VTE with an incidence up to 20- 30% per year. Patients are often placed on anticoagulation to reduce the risk of VTE. However, patients with primary brain tumors such as HGG are at increased risk for intracerebral hemorrhage (ICH) even without the administration of anticoagulation. The combination of risk factors for ICH with anticoagulation and HGG complicates decision-making. Currently it is not known which of the direct oral anticoagulants (DOACs) are safest for patients with HGG in terms of adverse bleeding-related outcomes such as ICH. Furthermore, a deeper understanding of the clinical and molecular determinants of bleeding-related adverse outcomes in HGG is not fully characterized. In this study, we gathered data on patients with HGG from two Ascension Seton Hospitals in the Austin metro area from July 1, 2017 through June 30, 2022. We identified 76 pathology-confirmed patients with HGG. Patients who were on rivaroxaban (3/7 (43%), p=.022) had a statistically significant association with more bleeding-related adverse events compared to those on apixaban (0/12 (0%)) or enoxaparin (0/5 (0%)) even though the groups were similar in terms of their characteristics including total time on the respective anticoagulation. Patients on anticoagulation vs those never on anticoagulation did not differ in terms of their studied demographic and clinical characteristics. Intriguingly, logistic regression analysis revealed that patients harboring isocitrate dehydrogenase (IDH) mutations had a statistically significant association with more adverse bleeding-related events even when controlling for other relevant factors (Odds Ratio compared to reference GBM: 115.7; p=.014). This study offers insights into our understanding of relevant factors associated with worse bleeding-related adverse outcomes such as ICH in patients with HGG.