What is hormone therapy for breast cancer?

Some breast cancers need the hormones estrogen or progesterone to grow. Hormone treatment keeps these cancers from getting the hormones they need. It's like starving the cells so that they stop growing. And the tumor sometimes shrinks.

Different types of medicines are used for hormone treatment. The treatment works by lowering the amount of hormones your body makes or by blocking the hormones from getting inside the cancer cells.

Sometimes the ovaries are removed with surgery or treated with radiation. This is done to stop the ovaries from making estrogen.

Hormone treatment may be used:

• After treatment for early-stage breast cancer. This reduces the chances that the breast cancer will come back.
• To prevent breast cancer in women who have a higher risk. It can help lower their risk.
• To treat advanced breast cancer or breast cancer that has spread beyond the breast.

Some types of endocrine therapy for breast cancer include:

Selective estrogen receptor modulators (SERMs).

Examples are raloxifene and tamoxifen.

Antiestrogen medicines.

An example is fulvestrant.

Aromatase inhibitors.

Examples are anastrozole and letrozole.

LH-RH agonists.

Examples are goserelin and leuprolide.

Some breast cancers need the hormones estrogen or progesterone to grow. Hormone treatment keeps these cancers from getting the hormones they need. The cancer cells stop growing and the tumor sometimes shrinks. The treatment works by lowering the amount of hormones your body makes or by blocking the hormones from getting inside the cancer cells.

The side effects of hormone treatment depend on the drug that is used.

Selective estrogen receptor modulators (SERMS).

The most common side effects are hot flashes, mood swings, and feeling very tired. These drugs may also raise your risk for blood clots, stroke, and endometrial cancer.

Aromatase inhibitors.

These can cause headaches, nausea, diarrhea, aching joints, and hot flashes. Using these medicines for a long time may cause bone thinning.

GnRH agonists and LH-RH agonists.

These drugs can cause hot flashes, mood swings, and vaginal dryness. They can cause less interest in sex, trouble sleeping, and headaches. Risks also include bone thinning.

Fulvestrant.

Common side effects include nausea, lack of energy, and weight gain. It may also cause vomiting, diarrhea, headache, back pain, and hot flashes.

Side effects of surgery

Removing your ovaries makes you start menopause, if you haven't started it yet. Menopause often has symptoms like hot flashes, vaginal dryness, urinating often, and having less interest in sex. And it raises your risk for other diseases, like heart disease and osteoporosis.

When your ovaries are removed, you can no longer get pregnant.