Pheochromocytoma history and symptoms

Overview
A pheochromocytoma (phaeochromocytoma outside of the US) is a neuroendocrine tumor of the medulla of the adrenal glands (originating in the chromaffin cells) or extra-adrenal chromaffin tissue which failed to involute after birth, which secretes excessive amounts of catecholamines, usually epinephrine and norepinephrine. Extra-adrenal paragangliomas (often described as extra-adrenal pheochromocytomas) are closely related, though less common, tumors that originate in the ganglia of the sympathetic nervous system and are named based upon the primary anatomical site of origin.

History and symptoms
The signs and symptoms of a pheochromocytoma are those of sympathetic nervous system hyperactivity, including:


 * Elevated heart rate
 * Elevated blood pressure, including paroxysmal (sporadic, episodic) high blood pressure, which sometimes can be more difficult to detect; another clue to the presence of pheochromocytoma is orthostatic hypotension (a fall in systolic blood pressure greater than 20 mmHg or a fall in diastolic blood pressure greater than 10 mmHg on making the patient stand)
 * Palpitations
 * Anxiety often resembling that of a panic attack
 * Diaphoresis
 * Headaches
 * Pallor
 * Weight loss
 * Localized amyloid deposits found microscopically
 * Elevated blood glucose level (due primarily to catecholamine stimulation of lipolysis (breakdown of stored fat) leading to high levels of free fatty acids and the subsequent inhibition of glucose uptake by muscle cells. Further, stimulation of beta-adrenergic receptors leads to glycogenolysis and gluconeogenesis and thus elevation of blood glucose levels).

A pheochromocytoma can also cause resistant arterial hypertension. A pheochromocytoma can be fatal if it causes malignant hypertension, or severely high blood pressure. This hypertension is not well controlled with standard blood pressure medications.

Not all patients experience all of the signs and symptoms listed. The most common presentation is headache, excessive sweating, and increased heart rate, with the attack subsiding in less than one hour.

Tumors may grow very large, but most are smaller than 10 cm.

Tumor Location
In adults, 90% tumors are located unilaterally and are solitary, and 10% are located outside the adrenal gland. In children 50% are adrenal, while 25% are bilateral and 25% are extraadrenal. The common extradrenal locations are the abdomen, thorax and urinary bladder.