Hormones that every woman has in her body -- estrogen and progesterone -- can serve as fuel for some types of breast cancer. They help the cells grow and spread. Hormone therapy, also called endocrine therapy, adds, blocks, or removes those chemicals to treat the disease.
Being at "high" risk for being diagnosed with breast cancer is different than being at high risk for a recurrence of breast cancer.
Research shows breast cancer is more likely to come back after treatment in women who had:
Cancer in the lymph nodes under the arms
A large tumor
An aggressive type of cancer
Negative hormone receptors
Positive HER2 receptor
Breast cancer can recur or come back in three ways:
The cancer can return at the original site. This is called a...
Drugs that stop estrogen and progesterone from helping breast cancer cells grow.
Drugs or surgery to keep the ovaries from making the hormones.
Hormone therapy is different from hormone replacement therapy (HRT), a treatment that adds hormones to the body to counter the effects of menopause.
Who Gets Hormone Therapy for Breast Cancer?
When you’re diagnosed with breast cancer, your doctor will test cells from your tumor to see if they have parts on their surfaces called receptors that use estrogen or progesterone. If they do, it means that they depend on these hormones to grow. In that case, your doctor will probably recommend hormone therapy as part of your treatment plan.
Tamoxifen is a pill that doctors have prescribed for more than 30 years to treat breast cancer. It works by blocking estrogen from attaching to the cancer cells.
Doctors first used tamoxifen to treat women whose breast cancer had spread in their bodies because it slowed or stopped the growth of the disease. The drug also lowers the chance that some early-stage breast cancers will come back. And it can lower the risk that a woman will get cancer in her other breast later on.
Women who are at high risk for breast cancer can take tamoxifen to try to lower their chances of getting the disease. It’s an alternative to watchful waiting or having surgery to remove a breast, called a mastectomy, before they get the disease.
Tamoxifen is an option for:
Treatment of the earliest form of breast cancer, ductal carcinoma in situ (DCIS), along with surgery.
Treatment of abnormal cells in the glands that make milk, called lobular carcinoma in situ (LCIS), to reduce the risk that they’ll become more advanced breast cancer.
Treatment of breast cancer in men and women whose cancers use estrogen.
Treatment of breast cancer that has spread to other parts of the body or that comes back after treatment.
To prevent breast cancer in women at high risk for the disease.