pheochomocytom

2. PHEOCHROMOCYTOMA
 Pheochromocytoma is a tumor that is usually benign and originates
from the chromaffin cells of the adrenal medulla.
 In 80% to 90% of patients, the tumor arises in the medulla; in the
remaining patients, it occurs in the extra-adrenal chromaffin tissue
located in or near the aorta, ovaries, spleen, or other organs.
 Pheochromocytoma may occur at any age, but its peak incidence is
between ages 40 and 50 years

3.  Pheochromocytoma is the cause of high blood pressure in 0.2% of
patients with new onset of hypertension.
 Pheochromocytoma may occur in the familial form as part of multiple
endocrine neoplasia type 2;

4. Clinical Manifestations
 The nature and severity of symptoms of functioning tumors of the
adrenal medulla depend on the relative proportions of epinephrine
and norepinephrine secretion.
 The typical triad of symptoms comprises headache, diaphoresis, and
palpitations.
 Hypertension and other cardiovascular disturbances are common.
 Other symptoms may include tremor, headache, flushing, and anxiety.

5.  Hyperglycemia may result from conversion of liver and muscle
glycogen to glucose by epinephrine secretion; insulin may be required
to maintain normal blood glucose levels.
 The clinical picture in the paroxysmal form of pheochromocytoma is
usually characterized by acute, unpredictable attacks lasting seconds
or several hours.
 During these attacks, the patient is extremely anxious, tremulous, and
weak.
 The patient may experience headache, vertigo, blurring of vision,
tinnitus, air hunger, and dyspnea.

6.  Other symptoms include polyuria, nausea, vomiting, diarrhea,
abdominal pain, and a feeling of impending doom.
 Palpitations and tachycardia are common.
 Blood pressures exceeding 250/150 mm Hg have been recorded.

7.  Such blood pressure elevations are life-threatening and may cause
severe complications, such as cardiac dysrhythmias, dissecting
aneurysm, stroke, and acute renal failure.
 Postural hypotension occurs in 70% of patients with untreated
pheochromocytoma.

8. Assessment and Diagnostic Findings
 Pheochromocytoma is suspected if signs of sympathetic nervous
system overactivity occur in association with marked elevation of
blood pressure.
 These signs can be associated with the “five Hs”: hypertension,
headache, hyperhidrosis (excessive sweating), hypermetabolism, and
hyperglycemia.

9.  Factors that may elevate catecholamine levels must be controlled to
obtain valid results; these factors include consumption of coffee or tea,
use of tobacco, emotional and physical stress, and use of many
prescription and over-the-counter medications (eg, amphetamines,
nose drops or sprays, decongestant agents, and bronchodilators).

10.  Imaging studies, such as CT scans, MRI, and ultrasound, may also be
carried out to localize the pheochromocytoma and to determine
whether more than one tumor is present.
 I-metaiodobenzylguanidine (MIBG) scintigraphy may be required to
determine the location of the pheochromocytoma and to detect
metastatic sites outside the adrenal gland.

11. SURGICAL MANAGEMENT
 The definitive treatment of pheochromocytoma is surgical removal of
the tumor, usually with adrenalectomy.
 Bilateral adrenalectomy may be necessary if tumors are present in both
adrenal glands.
 Administration of antihypertensive medications
 Intravenous fluid administration
 Corticosteroid replacement is required if bilateral adrenalectomy has
been necessary.
Thanking you.