Phaeochromocytoma

Question 1

Definition

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

Aetiology

Answer 2

· Sporadic cases are of unknown aetiology

· Familial in up to 30%

· Familial cases are seen in patients with:
o MEN2a
o von Hippel-Lindau syndrome
o Neurofibromatosis type 1

Question 3

Epidemiology

Answer 3

· RARE

· < 0.2% of hypertensive patients

Question 4

Presenting symptoms (general)

Answer 4

· PAROXYSMAL episodes

· Headache (due to malignant hypertension)

· Sweating

Question 5

Presenting symptoms (cardio-respiratory)

Answer 5

o Palpitations

o Chest pain

o Dyspnoea

Question 6

Presenting symptoms (GI)

Answer 6

o Epigastric pain

o Nausea

o Constipation

Question 7

Presenting symptoms (neuro-psychiatric)

Answer 7

o Weakness

o Tremor

o Anxiety

Question 8

Signs on physical examination

Answer 8

· Hypertension
· Postural hypotension
· Pallor
· Tachycardia
· Fever
· Weight loss

Question 9

Investigations

Answer 9

· 24 hr urine collection - check for catecholamine levels (and check for fractionated metanephrine levels)
o NOTE: metanephrines are metabolites of adrenaline

· Plasma free metanephrines

· Tumour localisation (MRI or CT)

· I-MIBG scintigraphy (another way of visualising the tumour)

· Screen for associated conditions

· Genetic testing