Mechanisms and treatment of venous thromboembolism in patients with brain cancer: a narrative review.

Malignant brain tumors, including both primary brain cancer and metastatic brain cancer, are associated with a markedly increased risk of venous thromboembolism (VTE). Anticoagulation is challenging in this population, as these patients are not only at risk of thrombotic complications but also at high risk of bleeding. In this review, we examine current knowledge on the incidence, risk factors, pathophysiology, and management of brain cancer-associated VTE. In primary brain cancer, particularly in glioblastoma, expression of the procoagulant proteins podoplanin and tissue factor by tumor cells was found to be an important pathophysiological driver of hypercoagulability. Expression of these prothrombotic factors was found to be dependent on the genetic profile of the brain tumor. Clinical data on the treatment of VTE in brain cancer are limited and mostly based on observational studies. The risk of intracranial hemorrhage during anticoagulation remains a key concern. Data from retrospective studies suggest that direct oral anticoagulants may be associated with a lower bleeding risk than low-molecular-weight heparins. Pharmacological thromboprophylaxis in the ambulatory setting is not routinely recommended, largely due to the lack of trial data in this population. Future studies are needed to improve risk prediction, to clarify the underlying mechanisms of brain cancer-associated VTE, and to define safe and effective treatment strategies.