Pheochromocytoma
Pheochromocytoma
Clinical Presentation of Pheochromocytoma
- Symptoms
- Spontaneous severe anxiety: palpitations, sweating, panic.
- Physical Exam Signs
- Tachycardia (Rapid heart rate)
- Hypertension (High blood pressure)
Biochemical Pathophysiology
As a simplification…
- Dopamine
- We can attribute the agitation and possible psychosis to the surge in Dopamine.
- Norephine & Epinephrine
- The sympathetic nervous system "fight or flight" symptoms relate to the surge in norepinephrine and epinephrine.
Laboratory Testing
- We test for pheochromocytoma in patients with unexplained episodic hypertension (high blood pressure) with blood and urine collection of:
- Catecholamine metabolite levels
- Metanephrine levels
Tumor Appearance
- Pheochromocytomas are black staining tumors (remember this was the color of melanin, another tyrosine derivative, as well) that classically grow out of the adrenal gland.
- Extra-adrenal pheochromocytomas: paragangliomas, which derive from cancerous autonomic nervous system tissue.
- True to the anatomy of the autonomic nervous system – head/neck ANS paragangliomas are parasympathetic whereas thorax and abdominal paragangliomas are sympathetic.
10% Rule for Pheochromocytomas/Paragangliomas
Inaccurate but still a helpful memory tool:
- 10% are paragangliomas (ie, extra-renal).
- 10% are bilateral.
- 10% are malignant.
- 10% present in children.
- 10% are NOT associated with hypertension
- 10% contain calcification
- 30% are familial (ie, genetic). Genetic diseases include:
- Multiple endocrine neoplasia type II (MEN II)
- von Hippel-Lindau disease
- Neurofibromatosis type I
- Tuberous sclerosis
- Sturge-Weber syndrome