Preventive therapies for breast cancer

We wish that there was a cure for cancer. Understanding that cancer is hundreds of different diseases, we appreciate the complexity of such a goal, but it remains a dream. Maybe the perspective should be slightly altered; would it be even better to prevent cancer from ever developing?

Let me first remind us all that there is zero evidence that specific foods or diets or lifestyle choices prevent cancer. You can eat broccoli at every meal, and it may not make a whit of difference in the odds of having cancer. I am not going to say more about diet than the standard reminder that a healthy diet consists of lots of fruits and vegetables, limited red meat, and very limited processed food. We all know this.

For a few cancers, there are solid strategies to reduce risk. The best-known one, of course, is stop smoking to reduce the changes of lung or head and neck cancers. For breast cancer, the area of prevention has been widely studied, and there are some medical interventions that are helpful for women at high risk. In recent weeks, both the American Society of Clinical Oncology (ASCO) and the U.S. Preventive Services Task Force (USPSTF) have released updated recommendations on the use of medications to reduce this risk.

The last time their recommendations were published was in 2013, and the updated versions primarily differ in the addition of aromatase inhibitors. In 2013, the focus was on tamoxifen and raloxifene. Although these recommendations have been around for a while, the use of medications to reduce breast cancer risk is rather low. Part of the issue is that the assumption has been that primary care physicians make the decisions and prescribe these drugs, and that is not always comfortable for them. Using medications that are primarily intended to treat breast cancer may seem a reach to non-oncologists.

These recommendations were highlighted in a recent article in a primary care journal. This is important as it reaches those physicians who are in a position to consider their use. There has also been a serious attempt to be more specific with risk consideration and make it more clear who might benefit. For example, the ASCO statement recommends the use of an AI as an alternative to tamoxifene or raloxifene only for post-menopausal women who are at high risk for breast cancer. Women at high risk include those who have had a diagnosis of atypical hyperplasia, or who have an estimated 5-year risk of at least 3%. I suspect that it would also be smart to more regularly refer women to a genetic counselor to discuss their risk.

It is heartening that attention is being paid to trying to prevent breast cancer, and we can hope that progress is made in this and strategies to reduce risk of other cancers, too.