Breast cancer is a malignant tumor that begins and grows in the breast. Malignant tumors can grow and invade nearby tissues or travel to distant organs.
This progression is called metastasis. Breast cancer treatment aims to shrink and eradicate tumors as well as prevent future tumor growth.
Hormone therapy, also known as endocrine therapy, can be used to treat some types of breast cancer. It’s commonly combined with other treatments, such as surgery, radiation, or chemotherapy.
Read on as we explore the different types of hormone therapy, when it’s an option, and what you can expect with this treatment.
What is hormone therapy?
There are many types of breast cancer. If your cancer tests positive for estrogen receptors (ER) or progesterone receptors (PR), that means it’s using these hormones to grow and potentially spread.
Hormone therapy drugs help block production or stop these hormones from attaching to the hormone receptors (HR). These drugs are used as an active treatment to shrink, control, and eradicate the cancer. They can also lower the chance of recurrence.
Some drugs, such as tamoxifen, can be given to people who don’t have breast cancer but have a high risk of developing it. This is commonly called chemoprevention. It may help lower the chances of breast cancer developing in the first place.
Hormone therapy for breast cancer is not the same as hormone replacement therapy (HRT) used for menopause.
When is hormone therapy used?
Hormone therapy is only effective for HR-positive tumors. If your breast cancer tumor is HR-negative, your oncologist will recommend other treatments.
Hormone therapy can be used in pre- or postmenopausal people with any stage of HR-positive breast cancer.
Hormone therapy that starts before surgery or radiation treatment is called neoadjuvant therapy. This can help shrink the tumor and make surgery easier.
When you begin hormone therapy treatment after surgery or radiation, it’s called adjuvant therapy. The goal here is to lower the risk that cancer will spread or come back.
According to the American Cancer Society, hormone therapy usually lasts at least 5 to 10 years
How does hormone therapy work?
Our bodies make a variety of hormones to help control how certain cells work.
Estrogen and progesterone are hormones that are mainly produced in the ovaries of premenopausal women. But they’re also produced in other tissues, so postmenopausal women and men have some estrogen and progesterone, too.
These hormones, however, can promote the growth of some breast cancers.
Treatments like surgery and radiation target specific areas of the body, such as the tumor site or lymph nodes. Because they focus on very specific areas, they’re considered localized treatments.
Hormone therapies, on the other hand, are considered systemic treatments because they target hormones throughout the body.
There are several types of hormone therapy, each with its own mechanism of action. They may help stop or slow growth or prevent recurrence by blocking: