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.

General examination

To diagnose gynaecomastia a detailed and full general examination is mandatory in the initial assessment of all endocrine patients.

Gynaecomastia may be the presenting feature in patients with documented or unrecognised congenital abnormalities which may have other non endocrine manifestations.

Height, weight, body habitus and BMI

Patients with generalised adiposity may present with non glandular breast swelling. Patients with Cushing’s syndrome have central adiposity, and may have short stature if the disease developed in childhood. 

Patients with Klinefelter’s tend to have tall stature.

Olfactory nerves

Anosmia should be assessed formally where possible as this symptom may not be reported by the patient, and otherwise a diagnosis of Kallmann's syndrome may not be considered.


Pubertal staging requires breast examination to be performed in all cases.

True gynaecomastia is present when the glandular tissue or breast bud is greater than 0.5cm in diameter.

Galactorrhoea should be confirmed and documented as either spontaneous or expressible by gently exerting pressure on both sides of the nipple.

Breasts and axillae should also be examined for masses particularly in the case of unilateral galactorrhoea.

Serum prolactin levels may increase after breast examination and so should always be checked before this is performed.

Cardiovascular examination

This should be assessed thoroughly in patients with suspected hypogonadism to seek evidence of heart failure.

Body hair

Secondary sexual hair should be assessed as part of pubertal staging and in all adults presenting with suspected hypogonadism.

Fine vellus hair is seen in patients with very low body mass and may be associated with hypothalamic hypogonadism.

Gastrointestinal system

Examine specifically for stigmata of chronic liver or renal disease.

External genitalia

Secondary sexual characteristics should be assessed as part of pubertal staging.

Testicular volume is particularly important in adult males with gynaecomastia and suspected hypogonadism, and should be documented using an orchidometer.

Testes should also be examined for abnormalities of texture, masses or lymphadenopathy as testicular tumours may present with gynaecomastia.


Poor muscle bulk may indicate gonadotropin deficiency.

Muscle wasting may also occur in glucocorticoid deficiency.

Proximal myopathy and slow relaxing reflexes may occur with loss of thyroid function.

Thyroid and thyroid status

Specifically seek signs of thyrotoxicosis which may disrupt gonadal function and present with gynaecomastia.

Pituitary status

Visual acuity and visual fields

Full assessment of acuity and fields is mandatory in all patients with possible pituitary disease, and so should be performed unless the diagnosis of Kallmann's, or isolated hypogonadotropic hypogonadism, has already been confirmed.

Visual fundoscopy

Disc pallor is indicative of long term visual loss which may not recover after decompression of the optic pathway.

Papilloedema is an indicator of raised intracranial pressure requiring urgent investigation.

Cranial nerves III-XII

Full cranial nerve assessment is important in all patients with suspected pituitary tumours.

The nerves of the cavernous sinus are most frequently affected, though a VI nerve palsy may be a false localising sign associated with increased intracranial pressure.


Fine wrinkling of the skin occurs in hypopituitarism.

Pallor may also occur with a normocytic normochromic anaemia with glucocorticoid deficiency.

Doughy pallid 'myxoedematous' skin may be seen with loss of thyroid function.

Bronze pigmentation may be seen in haemochromatosis.

Doughy skin with soft tissue swelling also occurs in growth hormone excess.

Café au lait patches, skin tags and axillary freckling may indicate associated syndromes, for example neurofibromatosis LINK, multiple endocrine neoplasia 2 LINK or McCune Albright syndrome.