Phaeochromocytoma

Question 1

What is pheochromocytoma?

Answer 1

tumour of chromaffin cells located in the adrenal medulla

Question 2

Sx of pheochromocytoma?

Answer 2

a. Marked HTN

b. Episodic symptoms: sudden and severe (

Question 3

Ix of pheochromocytoma?

Answer 3

1. Serum catecholamine (dopamine, adrenaline and NA)

2. Urine catacholemine (24 hour collection)

Question 4

Localisation of pheochromocytoma?

Answer 4

• CT scanning
• Meta iodo benzyl guanidine (MIBG) scan (functional nuclear medicine scan)
• Octreotide scanning
• Venous sampling

Question 5

Pre-operative Rx of pheochromocytoma?

Answer 5

a. Alpha adrenergic blockers:
Phenoxybenamine (40-100mg daily)
b. B blockers (if necessary, but never before a-blockade - only B blockade can lead to adrenal HTN crisis)
c. Rx of arrhythmias, cardiac failure and diabetes as required