Gynecomastia: Symptoms, Causes & Treatment

Gynecomastia is the enlargement of male breast tissue caused by excessive growth of the breast gland. It can occur when estrogen and testosterone levels are imbalanced, in cases of obesity, or with the use of certain medications.

This condition is most common during adolescence, but it can also affect newborns and older adults.

Gynecomastia can affect one or both breasts. In many cases it improves on its own, but if it persists, a doctor should assess the cause and recommend the most appropriate treatment, which may involve medication or surgery.

Main symptoms

The main symptoms of gynecomastia are:

• Increase in size of one or both breasts.

• One breast being larger than the other.

• Greater sensitivity in the breast or nipples.

• Breast pain, especially in adolescents.

• Swelling in the affected breast.

• A larger or darker areola, in some cases.

When gynecomastia affects only one breast, it is called unilateral gynecomastia. When it affects both breasts, it is called bilateral gynecomastia.

When both breasts are affected, the enlargement is usually uneven. This can lead to issues with self-esteem.

Confirming a diagnosis

Gynecomastia is diagnosed by an endocrinologist or a primary care provider based on symptoms, medical history, medication use, family history of gynecomastia, and a physical exam of the breasts, neck, thyroid, armpits, and testicles.

The provider may also order blood tests to check estrogen and testosterone levels, as well as tests to assess kidney, liver, and thyroid function.

In some cases, the provider may request imaging tests such as a mammogram, MRI, or CT scan of the breasts, a testicular ultrasound if needed, or a breast biopsy to rule out conditions with similar symptoms, such as breast cancer, lymphoma, or a dermoid cyst.

Possible causes

Gynecomastia develops when there is an imbalance between testosterone and estrogen, for example when testosterone activity is reduced or blocked, or when estrogen levels are relatively higher.

According to the Endocrine Society, this altered balance between these two hormones is the key mechanism that leads to gynecomastia.

Some factors that can lead to this hormonal imbalance include:

• Obesity or malnutrition.

• Hypogonadism or hyperthyroidism.

• Testicular infection.

• Klinefelter syndrome.

• Kidney failure, liver failure, or cirrhosis.

• Use of anabolic steroids or medications that contain estrogen.

• Use of drugs such as marijuana, amphetamines, or heroin.

Gynecomastia may also develop because of breast cancer or tumors in the testicle, adrenal gland, or pituitary gland, since these conditions can disrupt hormone balance.

It may also happen as a side effect of medications such as omeprazole, cimetidine, captopril, amlodipine, digoxin, amiodarone, amitriptyline, or clomipramine.

In addition, cancer treatment with chemotherapy or radiation therapy, as well as treatment for HIV infection, may cause breast enlargement in men.

Main types

Gynecomastia can be classified into several main types based on breast size, excess skin, and the characteristics of the breast tissue. The main types are:

• Grade 1: a small enlargement around the areola caused by a concentrated mass of glandular breast tissue, like a small button under the areola. There is no excess skin, although one breast may be slightly larger than the other.

• Grade 2a: a moderate increase in breast size without excess skin. The breast tissue usually collects in the lower part of the breast near the chest, and fat buildup may also be present and visible through clothing.

• Grade 2b: similar to grade 2a gynecomastia, but with excess skin in the breast area.

• Grade 3: the most advanced stage, in which breast tissue is spread more widely throughout the breast and there is excess fat and skin in the area.

Treatment for each type of gynecomastia depends on breast size and the amount of excess skin, and should always be guided by an endocrinologist.

Treatment options

Treatment for gynecomastia may involve:

1. Medical monitoring

Medical monitoring in this case is used only to observe how the breast tissue changes over time. It is mainly recommended for newborns, because this type of gynecomastia is caused by exposure to the mother’s estrogen during pregnancy and usually disappears on its own within 2 to 3 weeks after birth.

Adolescent gynecomastia that appears during puberty is also considered normal. According to the American Academy of Pediatrics, in most cases pubertal gynecomastia gets smaller over 2 to 3 years.

2. Medications

Medication may be recommended by the endocrinologist when the breasts do not shrink on their own or when there is swelling, pain, or tenderness in the affected breast.

The medications that may be used to treat male gynecomastia are:

• Tamoxifen or clomiphene (Clomid): block the effects of estrogen in the body.

• Anastrozole or letrozole: help prevent the formation of estrogen, which lowers the levels of this hormone in the body.

• Testosterone or danazol: act by increasing testosterone levels in the body.

These medications should only be used under the supervision of an endocrinologist and in doses tailored to each person.

3. Surgery

Surgery for gynecomastia may be recommended to reduce the size of the affected breast when the condition does not go away naturally within 2 years, interferes with daily activities, or causes embarrassment.

It may also be recommended when medications do not reduce breast size or when breast cancer is suspected.

The main types of surgery used for gynecomastia include:

• Liposuction: removes fat from the breast, but not the breast glands.

• Mastectomy: removes the breast gland tissue through small cuts in the skin, which usually allows faster recovery.

During adolescence, it is generally recommended to wait until puberty is finished before having surgery, to reduce the risk that gynecomastia will come back.

These surgeries usually take about an hour and a half and may be done with sedation plus local anesthesia or with general anesthesia, depending on the plastic surgeon. During the procedure, a half-moon-shaped incision is made around the nipple so excess breast tissue can be removed and sent for analysis to rule out cancer.