Pheochromocytoma Signs and Symptoms

• Pheochromocytomas are catecholamine-secreting tumors arising from chromaffin cells
• Adrenal medulla is the most common site of origin (approximately 90%)
  • However, tumors may develop anywhere along the abdominal sympathetic chain & are likely to be located near the aorta at the level of the inferior mesenteric artery or at its bifurcation

• Most cases of pheochromocytoma have no known cause
• In a substantial minority of cases, genetic abnormalities have been identified in some familial forms of pheochromocytoma, as well as those associated with MEN2A and MEN2B, von Hippel-Lindau disease, neurofibromatosis type 1, & paraganglioma syndromes

• Pheochromocytoma can occur at any age
  
  • Usually occurs during young to mid-adult life

• 10% of patients are asymptomatic

Majority of patients present w/ ≥1 of the following:

• Hypertension resistant to standard antihypertensive treatment
  
  • May be associated w/ headaches, excessive sweating &/or palpitations

• Hypertensive crisis w/ malignant hypertension, hypertensive encephalopathy, aortic dissection or myocardial infarction (MI)
• Paroxysmal symptoms which suggest seizure disorder, anxiety attacks or hyperventilation
  
  • Occurs in half of patients
  • Usually sudden in onset but variable in length (eg min-several hr)
  • Associated w/ headache, sweating, palpitations, apprehension, chest or abdomen pain, N/V
  • Pallor may occur
  • Very high BP usually w/ tachycardia

Other Symptoms

• Increased metabolic rate
  • Mild-moderate wt loss

• Orthostatic hypotension
  
  • Results from decreased plasma volume & dulled sympathetic reflexes

• Cardiac symptoms
  
  • Sinus tachycardia, sinus bradycardia & other arrhythmias
  • Acute MI or angina may occur even in the absence of coronary artery disease
  • ECG changes
  • Cardiomyopathy

• Multi-organ system failure w/ noncardiogenic pulmonary edema
• Carbohydrate intolerance
• Elevated hematocrit secondary to decreased plasma volume
• Hypercalcemia
• Fever, elevated erythrocyte sedimentation rate (ESR)
• Polyuria, occasionally rhabdomyolysis w/ myoglobinuric renal failure
• Hypokalemia