What You Need to Know About Unilateral Gynecomastia, or “One-Sided” Gynecomastia

one sided unilateral gynecomastia before treatmentGynecomastia is defined as the appearance of a female like breast in a male. It is related to excess proliferation of breast tissue due to an imbalance of the sex hormones estrogen and testosterone. While it is a benign condition that will not physically harm the individual, it can have a profound negative impact mentally. It’s important for men with gynecomastia to seek treatment. Gynecomastia typically presents as two-sided or “bilateral” growth, but in small percentage of men (less than 5-10%), it can present as single-sided “unilateral” or asymmetrical gynecomastia. Like bilateral gynecomastia, unilateral gynecomastia is a benign condition that is no different in terms of diagnosis and treatment. Unilateral gynecomastia is harder for men to deal with compared to the symmetrical or bilateral type.

this is asymmetrical gynecomastia and is an easy fix here at the Austin Gynecomastia CenterWatch


What Causes Unilateral Gynecomastia?

The clinical appearance of unilateral gynecomastia varies considerably. The gynecomastia can either be large or small in size and can appear very similar in appearance to a true female breast. For unknown reasons, it is more common to develop on the left side of the chest. It may or may not be associated with tenderness, which usually persists for only a short period of time unless you are taking medications that are causing inflammation of the tissue. The actual gynecomastia tissue itself is more commonly glandular – rather than the fibrous variety – for unknown reasons.

one sided unilateral gynecomastia surgery - tissue removedWe really don’t know why some men develop unilateral gynecomastia. Most cases of bilateral gynecomastia result from pubertal development or hormone use. Some studies have shown unilateral gynecomastia associated with various drugs. For instance, oral Finasteride or “Propecia” used to treat male androgenic alopecia (MAGA) has been associated with unilateral gynecomastia.

Unilateral gynecomastia can be caused by an acute infection process of the chest. This typically results in enlargement of the chest, pain, swelling and redness with fever and chills. It is treated with antibiotic therapy or possibly an evacuation of the infection collection, also known as an incision and drainage procedure. I have never seen this firsthand in my 30 years of practice. Benign masses and cysts can also occur on only one side of the chest and are usually easy to diagnose by an experienced clinician. These are treated by surgical removal of the benign mass.

A more serious cause of unilateral gynecomastia is male breast cancer. This is uncommon compared to cancer of the female breast and makes up less than 1% of all breast cancer diagnoses. Male breast cancer presents itself differently than gynecomastia, is typically clinically obvious and not challenging to diagnose. It is usually described as a firm mass that has been present for quite some time that may be stuck to the surrounding tissue. It is non-tender and may be associated with changes in the overlying skin, enlarged lymph nodes in the arm pit, drainage from the nipple itself and can cause ulceration of the skin in advanced cases. It occurs in older males and the average age at diagnosis is 67.

Risk factors for breast cancer in men include:

  • increasing age
  • race
  • family history of breast cancer

Increased levels of female sex hormones, obesity and gynecomastia are also associated with male breast cancer. Klinefelter’s syndrome (XXY) has been associated with a higher rate of breast cancer, as much as 50 times the average according to one study.

One-Sided Gynecomastia - Unilateral GynecomastiaWatch


How Can I Be Sure It Is Unilateral Gynecomastia?

The diagnosis of one-sided gynecomastia is performed by visual inspection. Special studies or radiological tests are not necessary unless your doctor suspects the possibility of breast cancer, in which case the work up is usually the same as it is for female patients – mammography, other radiology studies or even a biopsy. Again, this is quite rare and for most guys reading this information there is absolutely nothing to worry about. Unfortunately, I know of many patients who had a full work up for breast cancer when it clearly was not indicated. In fact, “cancer phobia” is one of the common psychological consequences of unilateral gynecomastia and reassurance is what is needed. There is no need to panic, especially if you have been searching with “Dr Google.” If you want assurances you need to seek out the expertise of a doctor who is knowledgeable and experienced with gynecomastia.

Unilateral GynecomastiaWatch


How Is It Treated? Can I Just Hide It?

Although it’s uncommon for anyone to have a perfectly symmetrical chest, pronounced unilateral gynecomastia will upset the balance and symmetry of the chest, which makes it very difficult, if not impossible, to hide with clothing or posture changes. A woman with two different sized breasts can wear a bra and pad the smaller breast, but this is not an option for men. Since we are programmed to “see” things that are exceptional or different, unilateral gynecomastia is very noticeable and brings unwanted attention towards it. This in turn only further adds to the psychological burden of gynecomastia. I even have known of patients who wore multiple compression garments or resorted to using duct tape to hide unilateral gynecomastia. Poor posture with flexion of the spine at the chest level and shrugging of the shoulders is a very common way to hide this condition and can lead to musculoskeletal imbalance.

Contrary to what you would think, the best treatment for unilateral gynecomastia is treatment on BOTH sides. I have learned that it is essential to treat both sides so that the result is smooth and symmetrical. There is usually some fullness on the smaller side that benefits from treatment so both sides look the same. If not, the smaller side will appear like it has gynecomastia after treatment! At the Austin Gynecomastia Center, the treatment of choice for almost all patients is the use of Vaser Ultrasonic liposuction to shrink the actual gynecomastia tissue, followed by the use of cannula liposuction to remove the “melted” gyno tissue and contour the surrounding fat. A small incision is made at the areola border to remove the gyno tissue, which can be seen in my videos.

Male Breast On One Side Unilateral GynecomastiaWatch


Seek The Expert In Treating Unilateral Gynecomastia

In summary, unilateral gynecomastia makes up about 5% of gynecomastia cases and is no different in diagnosis and treatment when compared to bilateral gynecomastia. Treatment is usually bilateral, and when performed by an expert, the results will be chest symmetry and liberation from both the mental and physical burden of gynecomastia.

Wondering if you have unilateral gynecomastia or details about treatment and want my expert opinion? Send me photos of your chest through my free online consultation form to find out.