New insights into cancer-associated thrombosis.

Venous thromboembolism (VTE) is an increasingly frequent complication of anticancer therapy. The underlying mechanisms are not completely understood, but are related in part to oncogene activation and tissue factor (TF) expression. Several risk factors have been identified including site and stage of cancer, patient comorbidities, and specific therapeutic agents. Candidate biomarkers such as blood counts, TF, and P-selectin have recently been identified. A risk model predictive of chemotherapy-associated VTE has been validated. Thromboprophylaxis with low molecular weight heparin (LMWH), unfractionated heparin (UFH), or fondaparinux is recommended for hospitalized medical and surgical cancer patients. Long-term anticoagulation with LMWH is safe and effective in reducing recurrent VTE in cancer. The role of thromboprophylaxis in ambulatory cancer patients receiving chemotherapy is an area of active investigation.