Phaeochromocytoma

• A phaeochromocytoma is a tumour of the adrenal glands that secretes unregulated and excessive amounts of catecholamines (adrenaline)
• Adrenaline


  Produced by the chromaffin cells in the medulla of the adrenal glands, stimulates the sympathetic nervous system, responsible for the "fight or flight" response
• Phaeochromocytoma


  A tumour of the chromaffin cells that secretes unregulated and excessive amounts of adrenaline
• Phaeochromocytoma symptoms


  Adrenaline tends to be secreted in bursts, giving intermittent symptoms
• Genetic disorders associated with Phaeochromocytomas

  • Multiple endocrine neoplasia type 2 (MEN 2)
  • Neurofibromatosis type 1
  • Von Hippel-Lindau disease
• In pheochromocytoma, adrenaline tends to be secreted in bursts, giving intermittent symptoms
• Genetic disorders more common in pheochromocytomas

  • Multiple endocrine neoplasia type 2 (MEN 2)
  • Neurofibromatosis type 1
  • Von Hippel-Lindau disease
• About 30-40% of patients with pheochromocytoma have a genetic cause
• 10% rule describing the patterns of tumors

  • 10% bilateral
  • 10% cancerous
  • 10% outside the adrenal gland
• Presentation of pheochromocytoma


  • Signs and symptoms tend to fluctuate, relating to periods when the tumor is secreting adrenaline
  • Symptoms include anxiety, sweating, headache, tremor, palpitations, hypertension, tachycardia
• Diagnosis of pheochromocytoma


  1. Initial tests include plasma free metanephrines, 24-hour urine catecholamines

  2. Measuring the serum catecholamine or adrenaline level is unreliable due to fluctuating levels and a very short half-life

  3. Metanephrines (a breakdown product of adrenaline) have a longer half-life with more stable levels

  4. Measuring 24-hour urine catecholamines gives an idea of how much adrenaline is being secreted by the tumor over 24 hours

  5. CT or MRI can be used to look for the tumor

  6. Genetic testing may be advised to look for a genetic cause (including relatives)
• Management of pheochromocytoma


  1. Management involves alpha blockers (e.g., phenoxybenzamine or doxazosin), beta blockers only when established on alpha blockers

  2. Surgical removal of the tumor

  3. Patients have their symptoms controlled medically before surgery to reduce the anesthesia and surgery risks