Thromboembolism in brain tumors.

Venous thromboembolism commonly affects patients receiving treatment for primary and secondary cerebral tumors. We review the recent literature on the molecular mechanisms underlying this hypercoagulable state and clinical studies of antithrombotic prophylaxis and therapy in this population. A computerized search of the MEDLINE database for articles from 1966 to the present day. Keywords/search terms used were glioma, astrocytoma, glioblastoma multiforme, cerebral tumor, primary brain tumour, secondary brain tumour, venous thromboembolism, thromboprophylaxis, heparin, warfarin, anticoagulants, and caval filters. Although neurological deficit has been identified as an independent risk factor for thrombosis it is also clear that malignant brain tumors induce changes in the makeup of circulating blood, making it more likely to clot. Concern for the perceived risk of perioperative intracranial bleeding with antithrombotic prophylaxis appears not to be justified by the available evidence. Prospective assessment of low molecular weight heparins for prophylaxis and treatment of established thrombosis is required. Antithrombotic therapy may also offer advantages over intracaval devices in prevention of secondary pulmonary embolism in patients with brain tumors.