Gynaecomastia

Condition by which males develop breast tissue due to an imbalanced ratio of oestrogen and androgen activity

Aetiology

• Usually a benign disease but breast cancer can develop in about 1% of cases

Physiological

• Physiological gynaecomastia most commonly occurs in adolescence, resulting from the delayed testosterone surge relative to oestrogen at puberty

• Less commonly it occurs in the older population, secondary to decreasing testosterone levels with increasing age

Pathological

• Lack of testosterone - causes include Klinefelter’s syndrome, androgen insensitivity, testicular atrophy, or renal disease

• Increased oestrogen - causes include liver disease, hyperthyroidism, obesity, adrenal tumours, or certain testicular tumours (e.g. Leydig’s cell tumours)

• Medication - causative agents include digoxin, metronidazole, spironolactone, chemotherapy, goserelin, antipsychotics, or anabolic steroids

• Idiopathic

Pathophysiology

• There is ductal growth without lobular development

Clinical presentation

• Often insidious onset

• On examination, gynaecomastia will present as a rubbery or firm mass (typically >2cm diameter) that starts from underneath the nipple and spreads outwards over the breast region

Investigations

• Tests are only necessary if the cause for gynaecomastia is unknown (especially if physiological or iatrogenic)

• In cases where malignancy is suspected, patients will require the triple assessment

• In cases where the causes in unknown, liver and renal function (U&Es and LFTs) should be checked initially, before checking the hormone profile if these are normal (LH and testosterone)

Management

• Depends on the causative factors and the phase of gynaecomastia

• If there is a reversible underlying cause, then treatment or reversal of this should also allow for the resolution of the gynaecomastia as well

• In most cases, reassurance may be enough for the patient