Gynecomastia (Enlarged Male Breasts)

Gynecomastia is an enlargement of the glandular tissue of the male breast. During infancy, puberty, and in middle-aged to older men, gynecomastia can be common. Gynecomastia must be distinguished from pseudogynecomastia or lipomastia, which refers to fat deposits in the breast area of obese men. True gynecomastia results from the growth of breast tissue, which is present in small amounts in men. The condition is the most common reason for medical evaluation of the male breast.

What causes gynecomastia?

Who gets gynecomastia?

Normally developing pubertal males and male infants may have gynecomastia.

Other risk factors include:

• Aging, which may promote decreases in testosterone production.
• Specific diseases and conditions (such as cirrhosis of the liver) that increase the risk of enlarged male breasts.
• Certain medications that may increase the risk of gynecomastia.

What causes gynecomastia during puberty? How long does it last?

Gynecomastia results from an imbalance in hormone levels, with increased estrogen levels relative to androgens. Gynecomastia that occurs in growing boys and resolves on its own is known as physiologic gynecomastia.

Both males and females have estrogen and androgens. During puberty, these hormone levels fluctuate, resulting in a temporary state with relatively high estrogen concentration. Studies on the prevalence of gynecomastia in adolescents have yielded varying results, reflecting differences in perception of normal and the ages of the boys studied.

Gynecomastia caused by hormone level changes usually disappears within six months to two years. Persistent gynecomastia is uncommon.

What diseases and conditions cause gynecomastia?

Several medical conditions may result in gynecomastia:

• Malnutrition and re-feeding, as well as cirrhosis of the liver, can create a hormonal environment that leads to gynecomastia.
• Disorders of the male sex organs (testes) can result in decreased testosterone production and high estrogen levels, leading to gynecomastia. Testicular cancers may also secrete hormones that cause gynecomastia.
• Other conditions associated with an altered hormonal environment, such as chronic renal failure and hyperthyroidism, may be associated with gynecomastia. Rarely, cancers other than testicular tumors may produce hormones that cause gynecomastia.

What medications cause gynecomastia?

Gynecomastia can be a side effect of many medications, such as:

• Spironolactone, a diuretic with anti-androgenic activity.
• Calcium channel blockers and ACE inhibitor drugs used to treat hypertension.
• Some antibiotics, anti-ulcer drugs, and medications used for prostate cancer.
• Other drugs, including methyldopa, highly active antiretroviral therapy (HAART) for HIV, digitoxin, diazepam, and drugs of abuse.
• Lavender oil and tea tree oil used in skin-care products have been associated with gynecomastia.

If you suspect gynecomastia, consult a healthcare professional.

What are the symptoms of gynecomastia?

The primary symptom of gynecomastia is an enlargement of the male breasts. Gynecomastia is the enlargement of glandular tissue rather than fatty tissue. It is typically symmetrical and may have a rubbery or firm feel. Gynecomastia usually occurs on both sides but can be unilateral. Tenderness and sensitivity may be present, but severe pain is uncommon.

The most important distinction is differentiating gynecomastia from male breast cancer, which accounts for about 1% of breast cancer cases. Breast cancer is usually confined to one side, feels hard or firm, and may be associated with skin dimpling, nipple retraction, nipple discharge, and enlarged underarm lymph nodes.

How is gynecomastia diagnosed?

Gynecomastia is diagnosed by the presence of breast tissue greater than 0.5 cm in diameter in a male. Gynecomastia is characterized by the presence of true breast tissue, generally around the nipple. Fat deposition is not considered true gynecomastia.

In most cases, gynecomastia can be diagnosed through a physical examination and medical history, including medication use. Mammograms may be ordered if there is suspicion of cancer. Further tests may be recommended to determine the cause of gynecomastia, including blood tests to examine liver, kidney, and thyroid function, as well as hormone level measurements.

What is the treatment for gynecomastia?

How long does it take for gynecomastia to go away?

Pubertal gynecomastia often goes away within about six months, so observation is preferred in many cases. Stopping medications and treating underlying conditions that cause enlarged breasts are also key treatments.

• Medical treatments are available, but data on their effectiveness are limited. No drugs have been approved by the FDA for gynecomastia treatment. Medications that have been used include testosterone replacement therapy, clomiphene, and tamoxifen.
• Surgery, specifically reduction mammoplasty, may be used in severe or long-term cases of gynecomastia where medications are ineffective.

Gynecomastia is not associated with long-term problems.

Are gynecomastia and male breast cancer related?

Men with gynecomastia have a higher risk of developing male breast cancer compared to the general population. Hormonal changes that cause gynecomastia in adult men also increase their risk of developing breast cancer, although gynecomastia itself is not a precancerous condition.

Can gynecomastia be prevented?

Gynecomastia caused by hormonal fluctuations cannot be prevented. Gynecomastia related to medical conditions can only be prevented if the underlying condition is prevented.

Brinton LA, Carreon JD, Gierach GL, McGlynn KA, Gridley G. "Etiologic factors for male breast cancer in the U.S. Veterans Affairs medical care system database." Breast Cancer Res Treat Mar. 29, 2009.