Gynaecomastia

Also called Enlarged breast tissue in men, Man boobs

Real breast tissue in men, not fat. Very common in teenagers and usually resolves; in an adult it needs a cause looked for.

What it is

Enlargement of genuine glandular breast tissue in males, distinct from fat, which is called pseudogynaecomastia.

It is extremely common at three ages: in newborns from maternal hormones, in adolescence, where it affects a majority of boys and usually resolves within a year or two, and in older men.

In an adult it should have a cause looked for rather than being accepted. The commonest is medication, and the list is long and includes drugs people would not suspect: spironolactone, some blood pressure drugs, cimetidine and omeprazole, some antipsychotics and antidepressants, finasteride, anti-androgens used for prostate cancer, and antiretrovirals.

Other causes are cirrhosis, chronic kidney disease, hyperthyroidism, low testosterone, Klinefelter syndrome, and, importantly, anabolic steroid misuse, which is a very common and rarely volunteered cause in younger men.

Rarely it signals a testicular or adrenal tumour, so the testicles should always be examined.

Male breast cancer is uncommon but real, and a hard, fixed, one-sided lump away from the nipple, with skin or nipple changes, needs urgent referral.

The psychological impact is substantial and frequently dismissed.

Signs you might notice

A firm, rubbery disc of tissue directly under the nipple, often tender, in one or both breasts.

Tenderness or discomfort, particularly in the early phase.

Sometimes nipple sensitivity.

Distinguishing features from fat: gynaecomastia is felt as a distinct disc centred on the nipple; fat is diffuse and soft.

Urgent referral: a hard, irregular or fixed lump; a lump away from the nipple; skin dimpling, nipple retraction or discharge; enlarged armpit nodes; or rapid one-sided growth.

Also assess: a testicular lump, signs of liver disease, or symptoms of thyroid disease.

Ask directly, without judgement, about anabolic steroid use in a younger man.

How it can affect day-to-day life

In adolescents the most useful thing is honest reassurance with a timeframe: it is normal, it happens to most boys, and it usually settles within one to two years. Without that, boys avoid swimming, changing rooms and sport, sometimes for years.

The psychological effect is significant and is routinely underestimated by clinicians, who see a benign finding. Body image distress here is real and can be severe.

Where a medicine is the cause, stopping or changing it often reverses it if done within the first year; after that, fibrosis makes it permanent, which is an argument for acting promptly rather than watching.

Weight loss helps pseudogynaecomastia and does not remove true glandular tissue, which is a common source of frustration.

Surgery is effective for established disease, and access on the NHS is limited and inconsistent, usually requiring significant psychological impact to be documented.

Anabolic steroid users often develop it and are reluctant to disclose; a non-judgemental question gets a more useful answer than an assumption.

Supporting someone well

Feel for the disc under the nipple; that is what distinguishes glandular tissue from fat.

In a teenager, give clear reassurance with a timeframe and check back rather than dismissing.

In an adult, review every medicine, including over-the-counter and herbal products.

Ask about anabolic steroids without judgement.

Examine the testicles, and get any lump assessed.

Check liver, kidney and thyroid function, and consider hormone tests.

Act within the first year where a reversible cause is found; after that it becomes permanent.

Get a hard, fixed or one-sided lump referred urgently.

Take the distress seriously and document it; it affects treatment options.

Where to get help

A GP practice for assessment and for a medication review.

Urgent breast clinic referral for suspicious features.

Endocrinology where a hormonal cause is suspected.

Breast Cancer Now on 0808 800 6000, who support men with breast concerns as well as women.