Venous Thromboembolism and Gancer: a Two-Way Clinical Association

Abstract

Venous thromboembolism and cancer are linked by a two way clinical association: venous thromboembolism may be the presenting feature of an occult cancer and patients with clinically overt cancer may develop a venous thromboembolic complication at any stage of their disease. Patients with venous thromboembolism in the absence of conventional risk factors have a 10% likelihood of having cancer. However, the value of investigating for underlying malignant disease in patients with idiopathic venous thrombosis who are otherwise well is still undefined: intensive diagnostic screening versus routine management is under evaluation in a randomised prospective clinical trial. Patients with cancer are at a high risk of developing postoperative venous thromboembolism. Therefore, they require prophylactic measures comparable to those usually recommended for major orthopaedic surgery. Both retrospective and prospective studies have recently focused attention on the thromboembolic risk associated with chemo- and/or hormone therapy in cancer patients. A prospective, double-blind, randomised study showed that very-low-dose warfarin is an effective and safe method for the prevention of thromboembolism in patients with metastatic breast cancer receiving chemotherapy. The evidence of lowered cancer mortality in patients receiving low molecular weight heparins has renewed interest in the antithrombotic agents as antineoplastic drugs. A multicentre study aimed at investigating this fascinating hypothesis is now being carried out.