Types of Hormone Therapy

Your medical oncologist can treat hormone receptor-positive cancer with hormone (endocrine) therapy. The main types are:

• Drugs that block estrogen receptors: These medications attach to the hormone receptors to prevent estrogen from reaching cancer cells, slowing cell growth. This hormone therapy is known as a selective estrogen receptor modulator (SERM), with tamoxifen the most widely recognized example. We may treat women with tamoxifen before or after menopause, as well as men with breast cancer. The drug’s uses in breast cancer treatment include:

• Drugs that lower estrogen throughout the body: The ovaries produce estrogen before menopause starts. If the ovaries no longer function because of menopause or another reason, an enzyme called aromatase can still produce small amounts of the hormone. Medications that stop the enzyme from producing estrogen are called aromatase inhibitors (AIs).

• Drugs that block male hormones called Androgens. The goal is to reduce levels of male hormones or to stop them from affecting prostate cancer cells. The main androgens in the body are testosterone and dihydrotestosterone (DHT).