Abnormal increase in the size of glandular breast tissue in a male patient. The diagnosis is clinical, but investigation is required to determine the underlying cause.
Detailed history of gynaecomastia, as well as pubertal development, is mandatory in all patients.
Peripubertal breast swelling is common and usually requires no treatment.
Long standing obesity may be associated with bilateral non glandular breast swelling. Centripetal obesity with gynaecomastia occurs in Cushing's syndrome.
Sudden onset and unilateral gynaecomastia should alert to the possibility of breast cancer.
Unilateral breast swelling, asymmetrical breast swelling, and changes in the skin of the breast, all raise the possibility of breast cancer requiring imaging in all cases.
Nipple discharge may occur with breast cancer, but bilateral galactorrhoea occurs with hyperprolactinaemia.
Physical discomfort commonly occurs with gynaecomastia due to hyperprolactinaemia rather than malignant causes.
The management of gynaecomastia will vary depending on whether a patient is asymptomatic, or has severe symptoms such as discomfort, galactorrhoea or embarrassment.
Assess timing of stages of puberty: the rate of change of height, timing of secondary hair development, increase in testicular and penile volumes, early morning erections, libido, and voice breaking. In a young man, this will often determine whether the gynaecomastia is likely to be physiological and peri pubertal, or whether there is an abnormality of pubertal development, and the gynaecomastia may be due to hypogonadism.
Shaving implies that at least in the past, the patient has had some gonadal function.
Patients with hypogonadism of any cause usually have a low libido, erectile dysfunction, and may not be sexually active.
Absent libido occurs with primary hypogonadism.
New onset loss of libido may be associated with hypogonadism though may be multifactorial.
Gynaecomastia may occur with thyrotoxicosis. Ask whether the patient has developed a tremor, weight loss, diarrhoea, anxiety or palpitations.
Headaches, visual disturbance with visual field loss, or symptoms of hypopituitarism should alert to the possibility of a macroprolactinoma or non functioning pituitary adenoma with elevated prolactin, as possible causes of gynaecomastia.
Anorexia nervosa and very low BMI of any cause may cause hypothalamic dysfunction and gynaecomastia.
Soya is known to contain large amounts of phytoestrogens which may interfere with the hypothalamic-pituitary-gonadal axis and may be associated with reversible gyncecomastia.
Steroids also interact with the hypothalamic-pituitary-gonadal axis and may be abused by some gym users, and may also occasionally be found in preparations thought by the patient to be 'natural' or 'herbal'.
Excessive exercise may lead to hypothalamic dysfunction.
Various agents associated with hypogonadism are listed below (although it is not exhaustive):
Opiates and recreational drugs, for example diamorphine, morphine sulphate, heroin, marijuana and alcohol.
Steroids, for example hydrocortisone, beclamethasone, fluticasone interfere with the hypothalamo-pituitary axis.
Exogenous testosterone, for example, used for fitness, body building or other sports, will also enhance estrogen synthesis.
Estrogens and drugs with estrogen-like activity, such as diethylstilbestrol and digoxin, will also cause gynaecomastia in some cases.
Phenytoin also enhances estrogen synthesis, as do gonadotropins.
A range of drugs can inhibit testosterone synthesis or action, including ketoconazole, metronidazole, alkylating agents, spironolactone, cimetidine, flutamide, finasteride, and etomidate.
Other agents such as methyldopa, tricyclic antidepressants, diazepam, penicillamine, omeprazole, phenothiazines, calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors have all been reported as causing gynaecomastia, though the mechanisms underlying this are unclear.
Patients may not report anosmia unless specifically questioned. Kallmann’s syndrome is typified by either anosmia or severe hyposmia and hypogonadotropic hypogonadism.
Dental aplasia, cleft palate and dental malalignment requiring orthodontic treatment may not be obvious and are associated with Kallmann’s syndrome.
Gynaecomastia may be the presenting feature of breast cancer, but also arises in other cancers including large cell lung cancer, gastric and renal cancers and hepatomas.
Chronic renal failure and renal cell carcinoma are both associated with gynaecomastia. Chronic liver disease, alcohol excess and congestive cardiac failure are also associated with gynaecomastia.
Congenital abnormalities of the urogenital system may also occur with Kallmann’s syndrome which may present with gynaecomastia.
Maldescent of the testes, previous mumps or viral orchitis, testicular trauma or testicular torsion all increase the chance of developing primary testicular failure which may present with gynaecomastia.
Multiple congenital conditions may affect pubertal development and be associated with gynaecomastia.
Patients with Klinefelter’s syndrome may also present with hypogonadotropic hypogonadism and gynaecomastia, and have an increased incidence of psychiatric problems.
Specifically ask if any family members, for example cousins, have had late or absent puberty, infertility or have never had children.
Symptomatic or asymptomatic orchitis may occur during infection with mumps. This may be associated with gonadal failure - hypergonadotropic hypogonadism, in later life.