From the Department of Medicine, University of Rochester, Rochester, NY (Francis) and the Department of Medicine, Duke University School of Medicine, Chapel Hill, NC (Kuderer)
Authors’ disclosures of potential conflicts of interest are found at the end of this article.
Address reprint requests to Charles Francis, MD, University of Rochester Medical Center, 601 Elmwood Ave., Box 704, Rochester, NY 14642; e-mail: charles_francis{at}urmc.rochester.edu
Overview: The hemostatic system plays an important role in the biology of cancer, and preclinical studies demonstrate that interaction of tumor cells with the hemostatic proteins is important in processes of angiogenesis, dissemination, and formation of metastases. Thrombosis is frequent in patients with cancer, activation of the hemostatic system can commonly be found, and animal models demonstrate that targeted lesions in hemostatic proteins can reduce tumor spread, growth, and metastases. Clinical studies also suggest that administration of anticoagulants favorably alters tumor biology. Patients with cancer form a substantial subgroup of patients enrolled in trials of anticoagulant therapy for venous thromboembolism. Meta-analyses of these studies have shown that patients who were randomly selected to receive low-molecular weight heparins had improved outcomes compared with those receiving unfractionated heparin. Several randomized controlled trials have been conducted to determine whether anticoagulant therapy improves survival of patients independent of thrombosis. Most studies have been small, have included a mixed tumor population, and have had variable results. Recently, reviews and meta-analyses have considered the effects on outcomes in patients with cancer. These have suggested a significant mortality risk reduction for patients treated with low-molecular weight heparins, with a small increase in bleeding complications. Taken together, these results indicate that anticoagulant therapy may offer a significant survival benefit for patients with cancer, and this should be pursued in larger prospective clinical trials.
