Treatment of thrombotic disorders in cancer patients.

Cancer patients are in a hypercoagulable state. The pathogenesis of thrombosis in malignancy is multifactorial with mechanisms including release of procoagulants by tumour cells, comorbid predisposing factors (bed rest, infection, surgery, etc.) and anti-cancer drugs. Cancer patients with established venous thromboembolism are more likely to develop recurrent venous thromboembolism during treatment with oral anticoagulants. This paper reviews the use of heparin for the treatment of thrombotic disorders in cancer patients. Treatment of acute venous thrombosis comprises initial heparin administration, which for a cancer patient should last for at least 5 days, followed by administration of oral anticoagulants. Low-molecular-weight heparins (LMWHs) have been shown to be as safe and effective as standard heparin for the treatment of acute deep vein thrombosis. Recent meta-analyses have revealed lower mortality rates with LMWH than with standard heparin, indicating that LMWH may exert an inhibitory effect on tumour growth that is not observed with standard heparin.