[Thromboprophylaxis in outpatients with cancer?]

Outpatients with cancer have an increased risk of venous thrombosis, especially during chemotherapy. Clinical trials have shown that thromboprophylaxis with low-molecular-weight heparin reduces the incidence of symptomatic venous thrombosis in these patients. An increase in major bleeding events was suggested but not confirmed in most recent trials. However, as the incidence of venous thrombosis is relatively low in the general cancer population, thromboprophylaxis should not be recommended for all cancer outpatients. Instead, to optimize the risk/benefit ratio, targeted thromboprophylaxis for patients deemed at high risk is recommended. Risk prediction models may be used to identify these high risk patients. Until results of clinical trials based on these models are published, thromboprophylaxis can be considered in patients with advanced or metastatic high risk cancers (e.g. pancreatic and lung cancer) who are receiving chemotherapy and have no increased risk of bleeding. Because of the many uncertainties, the decision to start thromboprophylaxis should always be discussed with the patient.