– Sympathetic nervous system tumour arising from adrenal medulla
– Paragangliomas arise from other parts of sympathetic chain
– Secrete catecholamines and associated with MEN II / Von Hippel Lindau (VHL)
– Catecholamines are derived from tyrosine
Clinical features
- May cause acute cardiac compromise and sudden death during routine medical exams
- Pheochromocytoma presentation
Diagnosis
- Urinary metanephrines – 3 x 24h collections
- Plasma catecholamines, CT, MRI
- Clonidine suppression tests – exclude if catecholamines significantly decreased
- MIBG Scan – uptake seen, useful in extra adrenal tumours
- Genetic testing – VHL syndrome / MEN II
Treatment
- Phenoxybenzamine [20-80mg] – complete alpha and beta adrenergic block
- Propranolol – [120-240mg]
- Whole blood transfusion
- Alpha must be blocked before beta to decrease hypertension risk
- Surgery after pharmacological treatment