[Show abstract][Hide abstract] ABSTRACT: The association between malignancy and the development of venous thromboembolism (VTE) is well recognized. The incidence of VTE in early breast cancer (EBC) is lower than in metastatic disease and a number of other common malignancies, but still presents a significant problem in terms of morbidity and mortality. The risk of VTE is further increased in patients receiving adjuvant chemotherapy for EBC, with the reported incidence ranging from 1.5% to 16.6%. It is unknown which chemotherapeutic agents or regimens are associated with the highest risk. Hormonal therapy also increases risk, most notably tamoxifen, but also, to a lesser extent, the aromatase inhibitors. Molecular targeting agents such as trastuzumab and bevacizumab are entering routine clinical practice for breast cancer and, although trastuzumab has not been shown to increase VTE, bevacizumab has been linked to the development of both venous and arterial thrombosis. At present, the use of thromboprophylaxis is not recommended for ambulatory patients being treated for EBC. However, risk analysis tools are emerging that may play some role in identifying high-risk patients who would benefit from prophylactic anticoagulation in the future. More prospective research is required to establish the risk of VTE with different chemotherapy regimens as well as newer targeted therapies. For now, clinical vigilance is required to ensure early VTE detection and optimal management to reduce morbidity and mortality.