- Phaeochromocytomas are neuroendocrine tumours of the adrenal medulla
- 10% multiple
- 10% extra-adrenal
- 10% malignant
- Extra-adrenal tumours are called paraganglionomas
- Most secrete adrenaline
- Some secrete noradrenaline and dopamine
- Clinical effects are due catecholamine excess
Clinical features
- Phaeochromocytomas account for 0.1% cases of hypertension
- Symptoms are often sporadic and paroxysmal
- Attacks may last minutes or hours and occur at variable intervals
- Include hypertension, palpitations, tachycardia and sweating
- 50% of patients develop chest pain
- Chronic effects include hypovolaemia and cardiomyopathy
- Phaeochromocytomas can be associated with:
- Multiple endocrine neoplasia syndrome (Type 2)
- Neurofibromatosis
- Von Hippel Lindau syndrome
Investigations
- To confirm diagnosis need to demonstrate catecholamine excess with
- 24-hour urinary vanniyl mandellic acid (VMA)
- 24-hour urinary total catecholamines
- Serum adrenaline or noradrenaline
- Tumour can be localised with:
- Abdominal CT
- MIBG (meta-iodobenzylguanidine) scanning
Picture provided by Suzanne Yoder, UCSD Medical Centre, San Diego, USA
Management
- Clinical features can not be controlled pharmacologically
- Need adrenalectomy after appropriate preoperative preparation
- Requires close cooperation between surgeon and anaesthetist
- Preoperative preparation requires:
- Alpha-blockade with phenoxybenzamine for at least 2 weeks preoperatively
- Volume expansion with intravenous fluids
- Beta-blockade after alpha-blockade
- Beta-blockade without alpha-blockade can cause a hypertensive crisis
- Intraoperative problems include:
- Hypertension associated with handling of the tumour
- Hypotension following devascularisation of the tumour
- Intraoperative blood pressure control achieved with fluids, nitroprusside and dopamine infusions
Picture provided by David Martin, Princess Alexandra Hospital, Brisbane, Australia
Bibliography
Peplinski G R, Norton J A.
The predictive value of diagnostic tests for phaeochromocytoma. Surgery
1994; 116: 1101-1110.
Roman S. Phaeochromocytoma and functional paraganglioma. Curr Opin Oncol 2004;
16: 8-12.
Williams D T, Dann S, Wheeler M H. Phaeochromocytoma - views on current management. EJSO
2003; 29: 483-490.
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