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Diseases and Conditions
Gynecomastia (enlarged breasts in men)
Special to CNN.com
Gynecomastia is swelling of the breast tissue in boys or men. It's caused by an imbalance of the hormones estrogen and testosterone. Newborns, boys going through puberty, and older men often develop gynecomastia from normal changes in hormone levels. Less often, gynecomastia is caused by a health condition such as liver disease, low testosterone production or a thyroid problem. Certain medications and illicit drugs that raise estrogen levels also can cause gynecomastia.
Gynecomastia isn't a serious problem unless it's a sign of an underlying health condition, but it can be tough to cope with. Men and boys with gynecomastia sometimes have pain or tenderness in their breasts and may feel embarrassed or unhappy with their bodies.
In most cases, gynecomastia will go away on its own. If it is caused by medications or illicit drugs, it usually goes away after they are stopped. Gynecomastia is often treated with medications that help balance hormone levels. In some cases, surgery to remove breast tissue is an option.
Signs and symptoms
Signs and symptoms of gynecomastia include:
- Swollen breast gland tissue
- Breast tenderness
- Nipple discharge
- Swollen nipples (especially in adolescent boys)
Gynecomastia is triggered by a decrease in the amount of testosterone compared to estrogen. This decrease can be caused by conditions that block the effects of or reduces testosterone or by a condition that increases estrogen levels. Several things can upset the hormone balance, including natural hormone changes, medications and certain health conditions. In about 25 percent of cases, the cause of gynecomastia is never found.
The testosterone-estrogen balance
The hormones testosterone and estrogen control the development and maintenance of sex characteristics in both men and women. Testosterone controls male traits such as muscle mass and body hair; estrogen controls female traits including the growth of breasts.
Most people think of estrogen as an exclusively female hormone, but men also produce it — though normally in small quantities. It helps regulate bone density, sperm production and mood. It may also have an effect on cardiovascular health. But male estrogen levels that are too high, or are out of balance with testosterone levels, can cause gynecomastia.
Gynecomastia in infants
Over half of male infants are born with enlarged breasts due to the effects of estrogen from their mothers. Generally the swollen breast tissue goes away within two to three weeks after birth.
Gynecomastia during puberty
Gynecomastia caused by hormone changes during puberty is very common, affecting over half of teenage boys. It is especially common in boys who are very tall or overweight. In most cases, the swollen breast tissue will go away without treatment within a few months to two or three years.
A number of medications can cause gynecomastia. These include:
- Anti-androgens used to treat prostate cancer and some other conditions. Examples include cyproterone, flutamide and finasteride.
- AIDS medications. Gynecomastia can develop in HIV-positive men on a treatment regimen called highly active antiretroviral therapy (HAART). It is especially common in men who are taking efavirenz or didanosine.
- Anti-anxiety medications such as diazepam (Valium).
- Tricyclic antidepressants.
- Ulcer medication such as cimetidine.
- Cancer treatment (chemotherapy).
- Heart medications such as digitalis and calcium channel blockers.
Street drugs and alcohol
Substances that can cause gynecomastia include:
- Anabolic steroids and androgens — gynecomastia occurs in as many as half of athletes who use these substances
Several health conditions can cause gynecomastia. These include:
- Hypogonadism. Any of the conditions that interfere with normal testosterone production, such as Klinefelter's syndrome or pituitary insufficiency, can be associated with gynecomastia.
- Aging. Hormone changes that occur with normal aging can cause gynecomastia, especially in men who are overweight.
- Tumors. Some tumors, usually involving the testes, adrenal glands, pituitary, lung and liver, can produce hormones that alter the male-female hormone balance.
- Hyperthyroidism. In this condition, the thyroid gland produces too much of the hormone thyroxine. This can lead to alterations in testosterone and estrogen that cause gynecomastia.
- Kidney failure.
- Liver failure and cirrhosis.
- HIV. The human immunodeficiency virus that causes AIDS can cause gynecomastia. Some medications used in the treatment of HIV also can cause gynecomastia.
- Chest wall injury.
- Spinal cord injury.
Risk factors for gynecomastia include:
- Older age — older men are at increased risk of gynecomastia
- Being overweight
- Use of anabolic steroids or androgens to enhance athletic performance
- Certain health conditions, including liver and kidney disease, thyroid disease, Peutz-Jeghers syndrome or other syndromes associated with hormonally active tumors, and Klinefelter's syndrome
- A family history of gynecomastia
Although there are few physical complications associated with gynecomastia, having this condition can cause psychological or emotional trouble caused by appearance. Gynecomastia slightly increases a man's risk for breast cancer.
When to seek medical advice
If you have swelling, pain, tenderness or nipple discharge in one or both breasts, see your doctor. Gynecomastia is common, especially during puberty, and usually doesn't require treatment. In some cases, however, swollen breast tissue is a sign of an underlying health problem such as a tumor or chronic illness.
Screening and diagnosis
Your doctor will ask you questions about your medical history, what medications you're taking, and what health conditions run in your family. The doctor will also do a physical examination that may include careful evaluation of your breast tissue, abdomen and genitals.
Your doctor will want to be sure your breast swelling is actually gynecomastia and not another condition. Other conditions that can cause similar symptoms include:
- Fatty breast tissue. Some men and boys have chest fat that resembles gynecomastia. This is called pseudogynecomastia or false gynecomastia, and it isn't the same as gynecomastia.
- Breast cancer. This is uncommon in men but can occur. Enlargement of one breast or the presence of a discrete firm nodule raises the concern for male breast cancer.
- A breast abscess (mastitis).
Initial tests to determine the cause of your gynecomastia may include:
You may need further testing depending on your initial test results, including:
- Chest X-rays
- Computerized tomography (CT) scans
- Magnetic resonance imaging (MRI) scans
- Testicular ultrasounds
- Tissue biopsies
Most cases of gynecomastia get better over time without treatment. However, if gynecomastia is caused by an underlying condition, that condition may need treatment. If you are taking medications that can cause gynecomastia, your doctor may recommend stopping them or substituting another medication.
In adolescents with no apparent cause of gynecomastia, the doctor may recommend a re-evaluation every six months to see if the condition improves on its own. In 90 percent of teenage boys, gynecomastia goes away without treatment in less than three years. However, treatment may be necessary if gynecomastia doesn't improve on its own, or if it causes significant pain, tenderness or embarrassment.
Medications used to treat breast cancer and other conditions may be helpful for some men with gynecomastia. Examples include:
- Anti-estrogen medications, such as raloxifene and tamoxifen.
- Aromatase inhibitors, such as letrozole, anastrozole and exemestane. These medications are generally not used in adolescents.
Surgery to remove excess breast tissue
If you still have significant bothersome breast enlargement despite initial treatment or observation, your doctor may advise surgery. Two types of surgery are used to treat gynecomastia:
- Liposuction. This surgery removes breast fat, but not the breast gland tissue itself.
- Mastectomy. This type of surgery removes the breast gland tissue.
Often, gynecomastia is caused by something that can't be prevented. But there are a few factors you can control that may reduce the risk of gynecomastia:
- Maintain a healthy weight. Men and boys who are overweight are more likely to have gynecomastia.
- Don't use illicit drugs. Examples include steroids and androgens, amphetamines, heroin, and marijuana.
- Avoid alcohol. Don't drink, or drink very little.
- Review your medications. If you're taking medication known to cause gynecomastia, ask your doctor if there are other choices.
For a man, enlarged breasts can be stressful and embarrassing. Gynecomastia can be difficult to hide and a challenge to romantic relationships. During puberty, gynecomastia can make boys a target for teasing from peers. It can make activities like swimming or changing for gym class traumatic.
Whatever your age, you may feel like your body has betrayed you and you may feel unhappy with yourself. These feelings are normal, but there are a few things you can do to help you cope:
- Get counseling. Talk therapy can help you avoid anxiety and depression caused by gynecomastia. It can also help you communicate with your partner or family members, so they understand what you're going through.
- Reach out to your family and friends. You may feel embarrassed to talk about gynecomastia with the people you care about. But explaining your situation and asking for help will likely strengthen your relationships and reduce stress.
- Connect with others who have gynecomastia. Talking with men who have had a similar experience can help you cope. Web sites such as Gynecomastia.org provide a forum for connecting with others who have the condition.