Phaeochromocytoma

Question 1

Define

Answer 1

• Catecholamine-producing tumours that usually arise from chromaffin cells of the adrenal medulla but are extra-adrenal in about 10% of cases.
o 10% are bilateral
o 10% are malignant
o Extra-adrenal phaeochromocytomas are referred to as paragangliomas

Question 2

What’s the aetiology/risk factors?

Answer 2

• Sporadic cases are of unknown aetiology
• Familial in up to 30%
• Familial cases are seen in patients with:
o Multiple Endocrine Neoplasia 2a and 2b
o von Hippel-Lindau syndrome
o Neurofibromatosis type 1

Question 3

Epidemiology?

Answer 3

• RARE

* < 1% of hypertensive patients

Question 4

What are the presenting symptoms?

Answer 4

•	PAROXYSMAL episodes 
•	Headache (due to malignant hypertension)
•	Sweating 
•	Cardiorespiratory Symptoms
o	Palpitations 
o	Chest pain 
o	Dyspnoea 
•	GI Symptoms
o	Epigastric pain 
o	Nausea 
o	Constipation
•	Neuropsychiatric Symptoms
o	Weakness 
o	Tremor 
o	Anxiety

Question 5

What are the signs?

Answer 5

• Hypertension
• Postural hypotension
• Pallor
• Tachycardia
• Fever
• Weight loss
• retinopathy

Question 6

What are the appropriate investigations?

Answer 6

• 24 hr urine collection - check for catecholamine levels (and check for fractionated metanephrine levels and creatinine levels
o NOTE: metanephrines are metabolites of adrenaline
• Plasma free metanephrines
• Screen for associated conditions
• Genetic testing (may reveal familial disorders)
• Tumour localisation (MRI or CT)
• I-MIBG scintigraphy (another way of visualising the tumour, high uptake intensity)