Thromboembolic complications associated with brain tumors.

Thromboembolic complications are the second most common cause of death in hospitalized cancer patients; they are caused by alterations of hemostasis and include hypercoagulable states, acute and chronic disseminated intravascular coagulation, and primary fibrinolysis. The fibrinolytic system is comprised of several serine protease enzymes and their inhibitors and is associated in various biological systems with physiological and pathological events such as tissue development, remodeling, invasiveness, and migratory potentials of both normal and malignant cells. It also plays a key role in the dissolution of fibrin strands. Defective fibrinolysis, which is often associated with the pathogenesis of venous thrombosis and other thromboembolic complications, occurs when the balance is disrupted, resulting in either inhibition or enhancement of fibrinolysis. The association between thromboembolic complications and neoplastic disease has been well-established since Trousseau in 1865 first reported a high incidence of venous thrombosis in a series of patients with gastric carcinoma. In this article, we discuss the factors that have been shown to be associated with thromboembolic complications in patients who harbor brain tumors, namely, hemostatic alterations caused by the tumors themselves or through interactions with neural tissue around the tumors, pre-operative hemostatic alterations in certain patients, and defective fibrinolysis associated with specific tumor types and/or tumor locations.