Effect of anticoagulant drugs in cancer

The aim of this review is to perform a critical analysis of all completed studies evaluating the role of anticoagulant agents in improving survival in patients with cancer. Furthermore, the rationale for testing anticoagulant drugs in this setting, and the recent basic research studies providing new evidence for a link between tissue malignant transformation of tissues and hemostatic proteins, are also briefly reviewed.

Four prospective randomized clinical studies to test the impact of low-molecular-weight heparin on mortality in cancer patients have been published. The results suggest a benefit from treatment, particularly in patients with nonadvanced disease. Inhibition of specific clotting pathways by anticoagulants may be hypothesized, particularly those involved in the malignant behavior of tissues. In the same vein, a direct action of anticoagulants on mechanisms of tumor growth and progression can be considered.

An antineoplastic effect of anticoagulant agents has often been suggested. Heparin and vitamin K antagonists have both been tested in this context. Heparin has been more extensively studied. Data from clinical trials of thromboprophylaxis in cancer patients have suggested that heparin may have beneficial effects on survival in these patients, with a major role for low-molecular-weight heparin compared with unfractionated heparin. Recently, the results of new prospective randomized clinical trials to evaluate the effect of low-molecular-weight heparin on cancer survival have become available. The published data look promising and provide an important step forward in the research knowledge in this field.