Gynaecomastia Flashcards
What is gynaecomastia?
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). It may also be present in newborns due to circulating maternal hormones, resolving as the maternal hormones are cleared.
Causes?
Gynaecomastia can be caused by conditions that increase oestrogen:
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
Gynaecomastia can be caused by conditions that reduce testosterone:
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)
There is a long list of medications and drugs that can cause gynaecomastia:
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
Assessment of gynaecomastia?
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.
The key points to cover in the history are:
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
The key points to cover in the examination are:
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)
Investigations?
Blood tests:
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)
Imaging:
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)
Management?
Stopping a causative drug (e.g., anabolic steroids or spironolactone)
Treatment options in problematic cases (e.g., pain or psychological distress) include:
Tamoxifen (a selective oestrogen receptor modulator that reduces the effect of oestrogen on the breast tissue)
Surgery
