Prevalence, causes, and impact of cancer-associated thrombosis

Despite advances in the treatment of venous thromboembolism (VTE) in the cancer population, cancer-associated thrombosis remains a serious and potentially life-threatening disease. This article will review the scope and impact of cancer-associated thrombosis, some of the possible risk factors, and current practice patterns.

Epidemiology data identify thrombosis as the second leading cause of mortality in cancer patients following the disease itself. The risk of recurrent VTE and all-cause death is 3-fold higher in patients with concurrent VTE and malignancy compared to non-cancer patients with VTE. It has been estimated that one in seven hospitalized cancer patients who die do so from a pulmonary embolism. Risk factors for cancer-associated thrombosis include tumor type, anti-tumor therapy, surgery, and immobility. Furthermore, an idiopathic VTE can be a predictor of occult malignancy, with one study suggesting that individuals who present with an unprovoked episode of VTE have a 10% frequency of subsequent cancer. The Fundamental Research in Oncology and Thrombosis (FRONTLINE) study collected data on the perceived risks and practice patterns with regard to VTE in cancer patients undergoing surgical and medical management of their malignancy. Additionally, the study provided information on international and regional practice patterns for the management of VTE in cancer patients. Respondents indicated that brain and pancreatic tumors were associated with an increased risk of VTE. Eight percent of respondents considered the use of central venous access lines to be associated with a high risk of VTE. The FRONTLINE study also indicated that surgeons are more likely to use thromboprophylaxis than medical oncologists and that low molecular weight heparins (LMWHs) are the most commonly used method for prevention of VTE.

Cancer patients are at greater risk of VTE and death compared to non-cancer patients; therefore, optimizing methods for the treatment and prevention of thrombosis is of particular importance in this population.