A quarter of all women in the United States die from heart disease. While cardiac disease is a public health issue in its own right, it is also linked to breast cancer because of the cardiotoxicity of common breast cancer treatments. Radiation (particularly to the left side), chemotherapy (such as anthracycline and adriamycin), and aromatase inhibitors (AIs) can all negatively impact heart health. Doctors worry that as more women survive breast cancer, women treated for early stage breast cancer are at greater risk of dying from cardiovascular disease than breast cancer.
We know that AIs reduce breast cancer deaths for women with operable estrogen receptor positive (ER+) breast cancer, which accounts for the majority of all breast cancers. But given the toxicity and concern about the long term harms from treatment for women surviving breast cancer, researchers are interested in seeing if some women can safely avoid using AIs after surgery.
Dr. Anne Blaes from Masonic University looked at endothelial function as a predictor of cardiovascular disease [S5-07]. Researchers compared 25 healthy postmenopausal women (the control group) with 36 postmenopausal women who had been treated with an aromatase inhibitor for locally advanced breast cancer between 2014-2015. They found that women who had been treated with AIs had reduced endothelial function, which predicts cardiovascular disease (acute coronary syndrome, chest pain, myocardial infarction, cardiac death).
This finding provides a caution about long-term cardiotoxicity of treatment to counterbalance the growing interest in extending hormone therapy. The study also raises questions about the use of AIs for “chemoprevention” in healthy women to reduce their risk of breast cancer. This is especially true for young women who may live decades after breast cancer. After all, it’s no good to prevent death from breast cancer at the cost of causing death from cardiovascular disease.