Some breast tumors need hormones to grow. Hormone therapy keeps cancer cells from getting or using the natural hormones they need, such as estrogen and progesterone, by reducing the production of hormones or blocking their action. Lab tests can show if a breast tumor has hormone receptors. If you have this kind of tumor, you may receive hormone therapy.
This treatment uses drugs or surgery:
Drugs — Your doctor may suggest a drug that can block estrogen. Another type of drug, called aromatase inhibitors, prevents the body from making the female hormone estradiol, a form of estrogen. If you have not gone through menopause, your doctor may give you a drug that stops your ovaries from making estrogen.
Surgery — If you have not gone through menopause, you may have surgery to remove your ovaries. The ovaries are the main source of the body’s estrogen. A woman who has gone through menopause does not need surgery because the ovaries produce less estrogen after menopause
The side effects of hormone therapy depend largely on the specific drug or type of treatment. The side effects of the drugs are similar to some of the symptoms of menopause.
– The most common are hot flashes and vaginal discharge. Other side effects are irregular menstrual periods, joint aches, headaches, fatigue, nausea, vomiting, vaginal dryness or itching, irritation of the skin around the vagina and skin rash. Not all women who take hormone therapy drugs have side effects.
– It is possible to become pregnant when taking hormone therapy drugs, and these medications may harm the unborn baby. If you are still menstruating, you should discuss birth control methods with your doctor.
– Serious side effects of hormone therapy are rare. However, it can cause blood clots in the veins. Blood clots form most often in the legs and in the lungs and increase the risk of stroke.
– Hormone therapy drugs can also cause cancer of the uterus; however, this is a very rare side effect. Your doctor should perform regular pelvic exams.
– When the ovaries are removed, menopause occurs immediately. The side effects are often more severe than those caused by natural menopause, and your healthcare provider can suggest ways to cope with these side effects.