Hormonal Therapy: Managing Side Effects in Women
Hormones are chemicals the body naturally makes to control the growth and activity of normal cells. Hormones can also speed the growth of some types of cancer. For example, the hormones estrogen and progesterone can stimulate the growth of some breast tumors.
Hormonal therapy is used to prevent or block hormones from speeding up the growth of cancer cells. It is also called hormone therapy or endocrine therapy. Different forms of hormonal therapy are used to treat breast, prostate, and endometrial cancers.
In general, there are 2 different approaches to hormonal therapy:
Surgical. Removal of an organ in the body that makes the hormone or hormones that stimulate cancer growth. For example, in men, the testes make testosterone. The testes can be removed with a procedure called an orchiectomy. This can slow the growth of some prostate cancers.
Medical. Medicines are used to block the hormones that stimulate cancer growth. For example, the medicine tamoxifen helps prevent estrogen from stimulating breast cancer growth.
The female hormones estrogen and progesterone promote the growth of some breast tumors. Hormonal therapy may be given to block these hormones from stimulating tumor growth.
Many breast cancer cells have proteins on their surfaces that can bind to estrogen. These proteins are called estrogen receptors. Tumors may also have progesterone receptors that bind to progesterone. When estrogen or progesterone binds to its receptor on the cancer cell, it signals that cell to grow.
Not all breast cancers have estrogen or progesterone receptors. In general, hormonal therapy is more effective in treating breast tumors that have hormone receptors than in treating tumors that do not have these receptors.
Hormonal therapy is used in women with advanced breast cancer that has spread (metastasized) to other parts of the body. It is also sometimes used in women who have been recently diagnosed with a large breast tumor to shrink the cancer before surgery (neoadjuvant therapy). It may also be used to prevent cancer from returning after surgery or radiation (adjuvant therapy). In some women who have a high risk of getting breast cancer, hormonal therapy is used to prevent cancer from developing.
Like other types of cancer treatment, hormonal therapy has side effects. An overview of hormonal therapies and ways to prevent or minimize these side effects are discussed below.
Types of hormonal therapies
A variety of hormonal therapies are available for breast cancer. Each type works a bit differently. But all have the same goal of starving the tumor of estrogen:
Selective estrogen receptor modulators (SERMs). SERMs are antiestrogen medicines that bind to the estrogen receptor. This prevents estrogen from binding to the receptor and stimulating cancer cell growth. SERMs include tamoxifen, toremifene, and raloxifene. They are taken as a pill.
Aromatase inhibitors. These medicines are used in older women who have been through menopause. Although the ovaries of these women no longer make large amounts of estrogen, male hormones (androgens) do circulate in the blood and can be changed into estrogen. An enzyme called aromatase carries out this change. Aromatase inhibitors prevent aromatase from changing androgens into estrogen. Anastrozole, letrozole, and exemestane are examples of aromatase inhibitors. They are taken as a pill.
Estrogen receptor antagonist. A newer class of hormonal therapy medicines is the estrogen receptor (ER) antagonist. One example is fulvestrant. It is given by a monthly shot into the muscle. Like SERMs, ER antagonists bind to the estrogen receptor and block estrogen from binding to it. They also also break down the estrogen receptor, lowering the number of receptors in the cell (downregulation).
Megestrol acetate. This is a progesterone-like medicine that may be used in women with advanced breast cancer who aren't helped by tamoxifen.
Ovarian ablation. The ovaries are the main source of estrogen in women who have not reached menopause. They may be removed by surgery through a procedure called oophorectomy. Or they may be made inactive by radiation therapy. Removing or inactivating the ovaries causes premature menopause and its symptoms, such as hot flashes and vaginal dryness. Loss of bone mass also occurs in menopause. When the ovaries are removed, a large amount of bone can be lost in a short time. This can lead to osteoporosis if it is not treated.
Side effects of hormonal therapy and ways to manage them
The side effects of hormonal therapy tend to be less severe than those caused by chemotherapy. In fact, some women have few symptoms or have side effects that get better with time. But when side effects do arise, it's important for women to report all symptoms to their healthcare provider. This includes even symptoms that are minor. Hormonal therapy is often taken for long periods of time. Symptoms can last throughout treatment if the they are not treated. Women should also always talk tith their provider about any alternative remedies they might want to try. Some alternative remedies can interfere with treatment.
Below are some ways to cope with some of the side effects of hormonal therapy.
More common side effects
A hot flash is also called a hot flush. It is a sudden rush of warmth to the face, neck, upper chest, and back, with or without sweating. This can last for a few seconds to an hour or more. This side effect is quite common with hormonal therapy. Some women have mild symptoms. Others have more severe effects. In many cases, hot flashes stop when hormonal treatment stops. Some women report that hot flashes last for years after treatment is finished. The following are some treatment options for managing hot flashes. Not all have been scientifically tested:
Megestrol acetate is a form of progesterone called progestin that seems to work to ease hot flash severity. It has some side effects, including breast tenderness, irregular vaginal bleeding, mood changes, and bloating.
Antidepressants, such as venlafaxine
Clonidine is normally used to lower high blood pressure, but it may be no better than a placebo, or dummy pill. Side effects include dry mouth, dizziness, drowsiness, and sleep difficulties.
Phytoestrogens are estrogens that come from plants. Soy products and some herbs contain phytoestrogens. Adding more phytoestrogens to the diet is commonly advised to ease the severity of hot flashes, but studies have shown conflicting results about how well they work.
Dietary changes. Don't have caffeine, alcohol, or spicy foods.
Clothing. Wear absorbent cotton clothing in layers that can be easily removed.
Sprays or moist wipes can help lower skin temperature.
Vaginal dryness and other vaginal issues
Vaginal dryness and vaginal discharge can be bothersome. Vaginal moisturizers and lubricants can help with this symptom. Vaginal moisturizers can be used as needed to keep the vagina moist. Water-soluble lubricants or any vaginal moisturizers can be used before sexual activity.
In addition to vaginal dryness, women may also have vaginal thinning and difficult or painful intercourse. Lubricants can help with some of these problems, as well.
Vaginal infections may also occur more often. Over-the-counter antifungal creams can provide relief for yeast infections. But talk with your gynecologist for symptoms that don't go away.
A common problem in women with cancer is fatigue or a lack of energy. Many things can cause fatigue. These include anemia, depression, pain, poor nutrition, medicines, and not enough sleep. Some ways to prevent fatigue are:
Go to bed at a regular time.
Take short power naps during the day.
Engage in an exercise routine, with your healthcare provider's supervision. For example, walk 10 to 30 minutes a day.
Eat healthy foods and drink fluids.
If anemia is contributing to fatigue, your provider may prescribe blood growth stimulators, such as epoetin alfa or blood transfusions.
Nausea and vomiting
This side effect is less common with hormonal therapy than it is with chemotherapy. Nausea often goes away on its own. Women can help manage symptoms by eating bland foods, such as crackers, toast, and cereal. Also drink lots of fluids–-6 to 8 glasses of liquids daily, such as water, broth, or electrolyte solutions. Your healthcare provider may advise antinausea or antianxiety medicines that prevent or treat nausea or vomiting. If you get dehydrated, you may need IV fluids.
Diarrhea is a less common side effect of hormone therapy. Dietary measures can help ease symptoms. Measures include eating a bland diet and staying away from foods such as dairy products and spicy foods. Medicines such as loperamide and diphenoxylate can be used to treat diarrhea.
Constipation is a less common side effect of hormone therapy. You may be able to ease symptoms by:
Exercising every day.
Eating foods high in fiber such as fruits and vegetables and whole-grain breads and cereals
Drinking lots of liquids—6 to 8 glasses a day
If these measures do not work, you may need a stool softener or laxative.
A daily exercise routine of 20 to 30 minutes per day and a weight management program can help. Talk with your healthcare provider before starting an exercise program. Another help is eating foods low in fat, such as fruits and vegetables.
Nervousness, depression, and anxiety are some of the symptoms that women may have. It is natural to have strong emotions in response to a diagnosis of breast cancer. These may become stronger when a woman gets hormonal therapy. Relaxation, meditation, and yoga may help control mood swings. Exercise may help boost mood and ease anxiety. Support groups and professional counselors may help some women. Your healthcare provider may also prescribe an antidepressant.
Pain, including pain in joints, back, and bones
Over-the-counter pain medicine can help ease mild to moderate pain in various parts of the body, such as the joints or back. Pain felt at an injection site can be treated with warm or cold compresses. You can also use an anesthetic cream on your skin. Talk with your healthcare provider about pain medicines, even over-the-counter ones.
Hormonal therapies such as the aromatase inhibitor anastrozole can increase coughing. Try to drink at least 8 glasses of fluid a day to keep the lining of your breathing tube moist. Use a humidifier to increase the moisture in the air. Your healthcare provider may prescribe medicines such as dextromethorphan, benzonatate, or guaifenesin to stop or control coughing.
Osteoporosis is a disorder in which bones become porous and break more easily. Women who have gone through menopause have a higher risk for bone loss. Some hormone therapies, such as tamoxifen, may lower bone loss in postmenopausal women. Other hormone therapies may not prevent or change a woman's risk of getting osteoporosis. For this reason, postmenopausal women with breast cancer should have a bone mineral analysis to find out if they need preventive therapy.
Women treated with hormonal therapy should have routine screenings (bone density scans) for osteoporosis. These suggestions are recommended for people at risk:
Take calcium and vitamin D supplements.
Get regular physical activity. This includes weight-bearing exercises that put stress on bones, such as jogging, stair climbing, dancing. It also includes resistance exercises, such as weightlifting. Talk with your healthcare provider about the right exercise program for you.
Drink less alcohol, if needed.
Medicines that prevent bone loss include the bisphosphonates risedronate, zoledronic acid, alendronate, denosumab, and calcitonin. Talk with your healthcare provider about which medicines are best for you.
Rare but serious side effects
Most side effects of hormonal therapy are not life-threatening. But in very rare cases, tamoxifen can raise a woman's chances of getting endometrial cancer. Women taking tamoxifen should report any unusual vaginal discharge, vaginal bleeding, menstrual irregularities, or pain or pressure in the lower abdomen to their healthcare provider. Get an annual pelvic exam to look for signs of cancer.
Some hormonal therapies carry a slight risk of blood clots forming in the deep blood vessels of the legs and groin. Clots can break off and spread to the lungs. Blood clots stop the flow of blood and can cause serious health problems. Signs of a blood clot in the lungs are sudden chest pain, shortness of breath, or coughing up blood. Symptoms of a blood clot in the legs include redness, pain, swelling, or tenderness in the groin or legs. Let your healthcare provider know if you have a history of blood clots. Get medical care right away if you have any symptoms of a blood clot.
Effects on the eye
Tamoxifen can cause cataracts or changes to the cornea and retina in the eye. Report any vision changes—including an inability to tell the difference between colors—to your healthcare provider.
Tamoxifen raises a woman's chance of having a stroke. Symptoms of stroke include:
Sudden severe headache
Trouble with seeing in one or both eyes
Difficulty walking or talking
Numbness of the face, arm, or leg
Get medical care right away for any symptoms of a stroke.
June 15, 2018
Bross, PF, FDA Drug Approval Summaries: Fulvestrant, The Oncologist (2002)7(6); pp. 477-480, Burstein, HJ., Adjuvant Endocrine Therapy for Women With Hormone Receptor, Journal of Clinical Oncology, 2014, 32(21); PP. 2255-2269
Levy, Adam S, MD,Sather, Rita, RN