March 2016 Ask the Expert: Hormonal Therapy
Hormonal therapy is medicine or surgery that lowers the amount of estrogen in the body. Your doctor may also call this type of treatment endocrine or anti-estrogen therapy. It is used for cancers that are hormone receptor-positive, meaning they depend on estrogen or progesterone to grow. Hormonal therapy is used to lower the risk of recurrence in early-stage breast cancer and to slow growth in
metastatic breast cancer.
In March, Living Beyond Breast Cancer expert Jennifer L.A. Armstrong, MD, answered your questions about hormonal therapy, including what treatments may be used, who may get it, why it may be offered and how it could affect the rest of your treatment and your risk of recurrence.
Remember: we cannot provide diagnoses, medical consultations or specific treatment recommendations. This service is designed for educational and informational purposes only. The information is general in nature. For specific healthcare questions or concerns, consult your healthcare provider because treatment varies with individual circumstances. The content is not intended in any way to substitute for professional counseling or medical advice.
There is data that suggests AIs work better than 5 years of tamoxifen. But now that there is data to support 10 years of tamoxifen, we do not know if 5 years of AI or 10 years of tamoxifen is better. Those trials have not yet been done.
For some women, the decision comes down to side effects. Tamoxifen protects the bones from osteoporosis. The AIs cause mild to severe joint aches in 30 to 70 percent of patients. (This varies depending on the study and method of reporting.) Because of this, many women with severe osteoporosis or arthritis opt for tamoxifen over AIs. But, because tamoxifen causes twice as many blood clots as AIs (4 percent vs. 1 to 2 percent), many women with a personal or family history of blood clots choose AIs. And tamoxifen slightly increases the risk of uterine cancer, so patients with concerns about this may opt for AIs.
Some women start with one and wind up switching to the other due to side effects (and this is OK)!
There is concern that risk of stroke or heart attack may be increased slightly but studies are ongoing to look into this further. Similarly, there may or may not be an increased risk of cataracts, a cloudiness that forms in the lens of the eye and affects vision. For this reason, it’s recommended that patients on hormonal therapy have an annual eye exam with an ophthalmologist.
We are not entirely sure. While patients often report this, studies have failed to show a cause-and-effect relationship. But this is being intensely investigated, and the data is evolving. Stay tuned…
It can be very hard to know the answer to this, because we do not yet have randomized studies comparing these options to each other. Often when a patient has a higher risk of recurrence, a more aggressive (and longer) course of anti-estrogen therapy is recommended. How strongly hormone-receptor positive a tumor is may also be taken into the equation.
In other words, a discussion with your team is needed to understand how the details of your tumor, and your health, may affect this decision.
There is a lot that can be done to reduce hot flashes. Reducing or avoiding caffeine and increasing exercise (to walking or running 10 miles a week, or another form of and amount of exercise that is equally challenging) can work quite well.
Patients are often surprised that one cup of coffee in the morning can lead to hot flashes that awaken them from sleep in the middle of the night, but this can happen.
There are also drugs that can help with hot flashes, especially SSRIs (such as venlavaxine, citalopram, or escitalopram). These medicines are most often used for depression and anxiety, but you don’t have to have those conditions to take them. Your medical team may be able to suggest other medicines that can also help, so talk to them about how you’re feeling.
It can be very hard to know. On the one hand, it is recommended that people in this situation still use contraception if they do NOT want to get pregnant. On the other hand, for patients who wish to become pregnant, referral to a gynecologist, an infertility specialist, or both, can be very helpful.
While there are hormonal levels that can be measured, recent studies have shown these hormonal levels (FSH and LH especially) are less predictive in this setting than in patients without a history of treatment for breast cancer.
It is not standard to remove the uterus and fallopian tubes when considering oophorectomy (removing the ovaries to reduce estrogen levels). Unless there are other medical issues unrelated to breast cancer, the risks of this kind of extensive surgery are felt to outweigh the benefits. But discussing this further with your medical team is recommended.
We are not entirely sure, but it is important to note that shutting down the ovaries with medicine (called chemical ovarian suppression) is reversible. Shutting down the ovaries with surgery is not reversible. That concern may be more relevant to patients with early-stage disease than those with metastatic disease.