NCOG-17. RETROSPECTIVE REVIEW OF THE TREATMENT OF VENOUS THROMBOEMBOLISM IN GLIOBLASTOMA PATIENTS RECEIVING BEVACIZUMAB

Abstract

Abstract Patients with malignant gliomas have an inherently high risk of venous thromboembolism (VTE).1 Bevacizumab is an anti-vascular endothelial growth factor (VEGF) monoclonal antibody commonly used in the treatment of recurrent high-grade gliomas and is known to increase the risk of VTE as well as intracranial hemorrhage.2 Anticoagulation (AC) for VTE also increases the risk intracranial hemorrhage in patients with malignant brain tumors.3 This makes the treatment of VTE in patients with GBM receiving bevacizumab therapy particularly challenging. Here we completed a single center retrospective chart review of patients with glioblastoma (GBM) treated concurrently with anticoagulation for VTE and bevacizumab therapy. The purpose of this review was to assess the safety of concurrent use of these therapies and to note any statistically significant difference in the incidence of hemorrhagic complications between patients treated with anticoagulation at therapeutic versus prophylactic dosing. METHODS: 144 patients with a diagnosis of high-grade glioma and were treated at UCI from 1/1/2019 through 1/1/2022 were screened for the study. 13 GBM patients on treatment with bevacizumab and concurrent anticoagulation were included. Clinical records of these patients were reviewed for the incidence of intracranial hemorrhage or any clinically significant bleeding. RESULTS: The incidence of ICH in GBM patients on concurrent therapy with bevacizumab and anticoagulation was 7.7% and the incidence of other minor bleeding complications was 7.7%. ICH and other minor bleeding was exclusively seen in patients on therapeutic anticoagulant dosing. No bleeding complications were noted in patients on prophylactic AC dosing. CONCLUSION: There is a risk of ICH in patients receiving both bevacizumab and anticoagulation, however compared to historical data, the incidence reported in our study is less than the incidence of ICH in GBM patients on anticoagulation alone. Our study suggests that it is relatively safe to treat patients with these therapies simultaneously.