Thromboprophylaxis Guidelines in Cancer with a Primary Focus on Ambulatory Patients Receiving Chemotherapy: A Review from the Southern Network on Adverse Reactions (SONAR)

Patients with cancer are at increased risk for venous thromboembolism (VTE). Factors related to cancer type, site, stage, duration, and extent of disease contribute to the oncology patient's risk of VTE. Patient-specific factors such as history of prior VTE and comorbidity are also contributory. The role of treatment-related factors, including chemotherapy regimen, has been a focus of recent investigation because most cases of VTE in the oncology setting occur in ambulatory patients. Thus, an emerging area of clinical research is primary VTE prophylaxis in the ambulatory cancer setting. Clinical guidelines currently recommend primary thromboprophylaxis in cancer patients who are undergoing surgery, who are hospitalized, and who are in a specific subset of high-risk ambulatory cancer patients. Validated risk stratification tools are essential for identification of patients who are at high risk of thrombosis. Emerging data from recently published clinical trials, as well as ongoing studies, are likely to advance our understanding of the potential utility of antithrombotic agents for primary prophylaxis in ambulatory patients with cancer and may influence future clinical guideline recommendations.