Hyperprolactinaemia & Prolactinoma

Question 1

What is the commonest functioning pituitary tumour

Answer 1

Prolactinoma

Question 2

Micro vs macro prolactinoma

Answer 2

Microprolactinoma <10mm
Macroprolactinoma >10mm

Question 3

Prolactinoma clinical presentation

Answer 3

• If macroprolactinoma - structural symptoms e.g.
  
  • headaches
  • visual field defects
  • panhypopituitarism
• Hyperprolactinaemia symptoms
  
  • FEMALES - galactorrhea, menstrual irregularity etc
  • MALES - impotence

Females tend to present early & men tend to present late
=> Men are more likely to present with structural symptoms

Question 4

Prolactinoma investigations

Answer 4

• Blood hormones tests (significantly raised serum prolactin)
• MRI pituitary (pituitary tumour)
• Anterior pituitary function tests (hypopituitarism?)
• Visual fields assessment

Question 5

Prolactinoma management

Answer 5

• Dopamine agonist - Cabergoline (first line therapy)
• Surgical removal (second line). If…
  - Dopamine agonist resistant or intolerant (side effects)
  - Dopamine agonist contraindicated

Question 6

Dopamine agonist side effects. What disease is it contraindicated in?

Answer 6

• (Cardiac) fibrosis => contraindicated in heart valve disease
• Psychiatric disturbances

Question 7

Causes of hyperprolactinaemia other than prolactinoma

Answer 7

Physiological
- Breastfeeding, pregnancy
- Stress, sleep

Drugs
- Dopamine antagonists e.g. metoclopramide
- Antipsychotics e.g. phenothiazines
- Anti-depressants e.g. SSRIs, TCAs, oestrogen, cocaine (less common)

Pathological
- Pituitary stalk damage e.g. iatrogenic, trauma
- Hypothyroidism
- Pituitary stalk compression due to adenoma

Question 8

How would you differentiate a prolactinoma from a pituitary adenoma compressing on the pituitary stalk

Answer 8

• Prolactinoma causes significantly raised prolactin
• Pituitary adenoma compression causes mildly raised prolactin