Gynaecomastia

Question 1

What is gynaecomastia?

Answer 1

Enlargement of glandular breast tissue in males
Due to inbalance between oestrogen and testosterone

Question 2

Physiological causes of gynaecomastia

Answer 2

• Oestrogen production peaks before testosterone during puberty
• newborns with circulating maternal hormones

Question 3

Why does obesity cause increased oestrogen?

Answer 3

Aromatase in adipose tissue converts androgens to oestrogen
Obesity > more adipose tissue

Question 4

Causes of gynaecomastia due to increased oestrogen

Answer 4

• obesity
• testicular cancer - leydig cell tumour
• liver cirrhosis + failure
• hyperthyroidism
• hCG secreting tumour e.g. SSLC

Question 5

Causes of gynaecomastia due to reduced testosterone

Answer 5

• testosterone deficiency in older age
• hypothalamus or pituitary conditions
• klinefelter’s syndrome
• orchitis
• testicular damage

Question 6

What medications can cause gynaecomastia?
And how

Answer 6

• spironolactone: inhibits testosterone production + blocks receptors
• anabolic steroids: increased oestrogen
• antipsychotics : increased prolactin
• digoxin: stimulates oestrogen receptors
• alcohol
• marijuana

Question 7

What is pseudo gynaecomastia?

Answer 7

Breast enlargement due to obesity

Question 8

Examination finding distinguishing between gynaecomastia + pseudo-gynaecomastia

Answer 8

Firm or rubbery tissue behind areola in gynaecomastia
Representing growth of gland + duct tissue

Question 9

Keys point in examination of gynaecomastia

Answer 9

• gynaecomastia vs pseudo-gynaecomastia
• unilateral or bilateral
• exclude breast cancer
• BMI
• testicular exam
• signs of testosterone deficiency
• signs of liver disease
• signs of hyperthyroidism

Question 10

Investigations of gynaecomastia

Answer 10

• bloods: LFTs, TFTs, horomone levels, LH, FSH, genetic karyotyping, alpha-fetoprotein + beta-hCG
• imaging: breast USS, testicular USS, chest X-ray, mammogram, biopsy | depending on what is suspected

Question 11

Testicular cancer tumour markers?

Answer 11

• alpha fetoprotein
• beta hCG

Question 12

What testicular tumours can cause gynaecomastia?

Answer 12

Leydig tumours

Question 13

Management of gynaecomastia

Answer 13

• work out underlying cause
• normally resolves in adolescents
• stop causative drug
• referral if cancer suspected
• tamoxifen
• surgery

Question 14

What do the levels of LH + testosterone indicate?
- high LH + low testosterone
- low LH + low testosterone
- high LH + high testosterone

Answer 14

• high LH + low testosterone - testicular failure
• low LH + low testosterone - increased oestrogen
• high LH + high testosterone - androgen resistance or gonadotrophin-secreting malignancy