Thrombosis and malignancy: pathogenesis and prevention

An increased incidence of thrombosis has been observed in cancer patients for over a century. The hypercoagulable state of malignancy results from multiple mechanisms including activation of the coagulation cascade and alterations of cellular blood components and endothelial cells by tumor cells. Studies have been done to determine the role of prophylactic anticoagulation therapy in cancer patients, and have shown to reduce safely the incidence of thrombosis in patients receiving treatment for metastatic breast cancer and in patients with implanted upper extremity venous catheters. Further studies are needed to determine the contribution of newly described genetic risk factors for thrombosis in order to stratify the risk for thrombosis in patients with cancer.