GYNAECOMASTIA
Definition
Gynaecomastia is a
condition of benign hyperplasia of the breast tissue in men and should be
distinguished from simple adiposity. Gynaecomastia develops as a result of a
relative excess of oestrogens over testosterone, either because of increased
production or action of oestrogens, or reduced production or action of
androgens (Figures 29.1 and 29.2).
Causes
• Physiological Most commonly in the newborn or
pubertal period. Around 50% of pubertal boys will have gynaecomastia at some
stage, but this is usually self-limiting.
• Drugs A common cause, whether
prescribed or taken recreationally. Examples include anti-androgens (e.g.
spironolactone), oestrogens, testosterone (stimulates aromatase), cannabis and
opiates.
• Hypogonadism (Chapter 28).
• Tumours Oestrogen or androgen-producing
testicular or adrenal tumours. HCG-producing tumours, usually testicular but
occasionally ectopic (e.g. lung).
• Systemic illness Classically, liver cirrhosis
(increased oestrogen and lower bioavailability of androgens due to high levels
of SHBG) but also chronic renal failure.
• Other conditions including obesity,
thyrotoxicosis and androgen insensitivity.
Many cases are
idiopathic with no clear underlying cause.
Assessment
The history should
elicit the duration and progression of gynaecomastia; recent and rapid onset
should lead to clinical suspicion of a tumour. Symptoms and signs of
hypogonadism (Chapter 28) and systemic disease (endocrine, hepatic or renal)
should be sought in addition to a careful drug history. The breasts should be
examined to confirm the presence of gynaecomastia and to document its extent.
The testes must be palpated to exclude a tumour and to assess size (androgenic
steroid abuse may, for example, lead to atrophy). Baseline blood tests should include
measurement of 09.00 testosterone, oestradiol, LH and FSH, SHBG, HCG and LFTs.
Depending on results, other tests may subsequently be required (e.g. tests for
hypogonadism; Chapter 28, testicular ultrasound and chest X-ray if raised HCG,
and abdominal CT or MRI if markedly raised oestradiol).
Treatment
If an underlying
disorder is identified this should be treated and offending drugs should be
stopped if possible. Physiological gynaecomastia is usually self-limiting and
does not generally require treatment. In persistent cases where there is
significant cosmetic concern, medical treatment with antioestrogens (e.g.
tamoxifen) can be tried, although success is variable and surgery is usually
preferred.
