[Secondary prevention of venous thromboembolism in patients with cancer].

Venous thromboembolism occurs in about 10% of patients with cancer. In this setting, vitamin K antagonists have been associated with a high risk of recurrent disease and major bleeding. Low-molecular-weight heparin allows reducing by 50% the rate of recurrent venous thromboembolism as compared to vitamin K antagonists. Even with low-molecular-weight heparin, recurrent venous thromboembolism occurs in up to 6% of the patients. In this case it has been suggested to increase the dosage of low-molecular-weight heparin. Vena cava filtration probably plays a minor role in setting. After the sixth month, prolongation of low-molecular-weight-heparin or switch to vitamin K antagonist should be discussed on a case by case basis.