Male breast conditions

Question 1

What is gynaecomastia?

Answer 1

Gynaecomastia refers to the enlargement of the glandular breast tissue in males.

Male breast enlargement is relatively common, particularly in adolescents and older men (aged over 50 years).

Question 2

How does gynaecomastia typically occur?

Answer 2

Generally caused by a hormonal imbalance between oestrogen and androgens (e.g., testosterone), with higher oestrogen and lower androgen levels.

Raised oestrogen stimulates breast development, whilst androgens have an inhibitory effect on breast development.

Question 3

An excess of what hormone can result in breast development?

Answer 3

Prolactin is a hormone that also stimulates glandular breast tissue development (as well as breast milk production). Therefore, raised prolactin (hyperprolactinaemia) can cause gynaecomastia.

Question 4

What has an inhibitory effect on prolactin?

Answer 4

Dopamine

Dopamine antagonists (e.g., antipsychotic medications) block dopamine production, which can allow prolactin levels to rise and cause gynaecomastia and galactorrhea (breast milk production).

Question 5

Cause of gynaecomastia?

Answer 5

Idiopathic (unknown cause)

Question 6

Gynaecomastia may be caused by conditions that increase oestrogen, what are some examples of these?

Answer 6

Obesity (aromatase is an enzyme found in adipose tissue that converts androgens to oestrogen)

Testicular cancer (oestrogen secretion from a Leydig cell tumour)

Liver cirrhosis and liver failure

Hyperthyroidism

Human chorionic gonadotrophin (hCG) secreting tumour, notably small cell lung cancer

Question 7

Apart from conditions that increase oestrogen , gynaecomastia can also be caused by conditions that lower testosterone. What are some examples of these?

Answer 7

Testosterone deficiency in older age

Hypothalamus or pituitary conditions that reduce LH and FSH levels (e.g., tumours, radiotherapy or surgery)

Klinefelter syndrome (XXY sex chromosomes)

Orchitis (inflammation of the testicles, e.g., infection with mumps)

Testicular damage (e.g., secondary to trauma or torsion)

Question 7

About 2% of patients with gynaecomastia present with a Leydig testicular tumour. True/false?

Answer 7

True

Question 8

Medications and drugs that can cause gynaecomastia?

Answer 8

Anabolic steroids (raise oestrogen levels)

Antipsychotics (increase prolactin levels)

Digoxin (stimulates oestrogen receptors)

Spironolactone (inhibits testosterone production and blocks testosterone receptors)

Gonadotrophin-releasing hormone (GnRH) agonists (e.g., goserelin used to treat prostate cancer)

Opiates (e.g., illicit heroin use)

Marijuana

Alcohol

Question 9

A large number of gynaecomastia cases are idiopathic however what is a common cause in young men presenting to clinic?

Answer 9

Anabolic steroids (raised oestrogen levels)

Question 10

How is gynaecomastia different from breast enlargement due to obesity (pseudogynaecomastia)?

Answer 10

On palpation, there will be firm tissue behind the areolas in gynaecomastia, representing growth of the gland and duct tissue. This is different to simple adipose (fat) tissue, which is soft and more evenly distributed.

Question 11

For gynaecomastia, what key aspects of the history are looked at?

Answer 11

Age of onset, duration and change over time

Associated sexual dysfunction (indicating low testosterone)

Any palpable breast lumps or skin changes (exclude breast cancer)

Associated symptoms that may indicate the cause (e.g., testicular lumps or symptoms of hyperthyroidism)

Prescription medication (e.g., antipsychotics, spironolactone or GnRH agonists)

Use of anabolic steroids, illicit drugs or alcohol

Question 12

For gynaecomastia, what key aspects are looked at for the examination

Answer 12

True gynaecomastia versus simple adipose tissue

Unilateral or bilateral

Any palpable lumps, skin changes or lymphadenopathy (exclude breast cancer)

Body mass index (BMI)

Testicular examination (e.g., lumps, atrophy or absence)

Signs of testosterone deficiency (e.g., reduced body and pubic hair)

Signs of liver disease (e.g., jaundice, hepatomegaly, spider naevi and ascites)

Signs of hyperthyroidism (e.g., sweating, tachycardia and weight loss)

Question 13

How are investigations for gynaecomastia determined?

Answer 13

By history and examination findings

Question 14

What blood tests can be done for gynaecomastia?

Answer 14

Renal profile (U&Es)
Liver function tests (LFTs)
Thyroid function tests (TFTs)
Testosterone
Sex hormone-binding globulin (SHBG)
Oestrogen
Prolactin (hyperprolactinaemia)
Luteinising hormone (LH) and follicle-stimulating hormone (FSH)
Alpha-fetoprotein and beta-hCG (testicular cancer)
Genetic karyotyping (if Klinefelter’s syndrome is suspected)

Question 15

What imaging tests can be used for gynaecomastia?

Answer 15

Breast ultrasound (may help assess the extent of gynaecomastia)
Mammogram (if cancer is suspected)
Biopsy (if cancer is suspected)
Testicular ultrasound (if cancer is suspected)
Chest x-ray (if lung cancer is suspected)

Question 16

Management of gynaecomastia?

Answer 16

Dependant on the underlying cause.

Stopping a causative drug (e.g., anabolic steroids or spironolactone) will usually resolve the symptoms. Patients may be referred to the specialist breast clinic where the cause is unclear or cancer is suspected.

Question 17

In problematic cases of gynaecomastia (e.g. pain or psychological distress), what are some treatment options?

Answer 17

Tamoxifen (a selective oestrogen receptor modulator that reduces the effect of oestrogen on the breast tissue)

Surgery

Question 18

What medication is associated with gynaecomastia?

Answer 18

Spironolactone