Tamoxifen may increase the risk of venous thromboembolism amongst women treated for breast cancer

A recent systematic review and meta analysis published in the British Medical Journal investigated the effect of endocrine therapies on a range of cardiovascular disease outcomes amongst women with non-metastatic breast cancer.Seven specific cardiovascular disease outcomes were examined (venous thromboembolism, myocardial infarction, stroke, angina, heart failure, arrhythmia, and peripheral vascular disease). The headline finding was an increased risk of venous thromboembolism in tamoxifen users compared with both non-users and aromatase inhibitor users. The choice as to use an aromatase inhibitor versus tamoxifen will primarily be based on the effectiveness against the recurrence of breast cancer, but this review reveals that risk of venous or arterial vascular disease is an important secondary consideration.