Phaeochromocytoma

Question 1

Where is adrenaline produced?

Answer 1

Chromaffin cells in the adrenal gland

Question 2

What is a pheochromocytoma?

Answer 2

Tumour of the chromaffin cells secreting unregulated + excessive amounts of adrenaline

Question 3

What kind of pattern do they symptoms follow in pheochromocytoma?

Answer 3

adrenaline secreted in bursts –> periods of worse symptoms followed by more settled periods

Question 4

Which condition are phaeochromocytomas associated with?

Answer 4

MEN 2

Question 5

What does the 10% rule mean?

Answer 5

10% bilateral
10% cancerous
10% outside the adrenal gland

Question 6

How is phaeochromocytoma diagnosed?

Answer 6

Plasma free metanephrines

24 hour urine catecholamines

Question 7

What are metanephrines and why are they measured instead of adrenaline?

Answer 7

A breakdown product of adrenaline
Adrenaline only has a half life of a few minutes in the blood
Metanephrines have a longer half life making them less prone to fluctuations –> more reliable diagnostic tool

Question 8

What are the clinical features of a phaeochromocytoma?

Answer 8

Anxiety
Sweating
Headache
Hypertension
Palpitations, tachycardia + paroxysmal AF

Question 9

How is a phaeochromocytoma managed?

Answer 9

Alpha blockers e.g. phenoxybenzamine
Beta blockers once established on alpha blockers
Adrenalectomy (definitive management)

Question 10

When should surgical removal be carried out?

Answer 10

Once the patients symptoms have been controlled medically

Symptoms –> high surgical and anaesthetic risk