Symptoms include sweating, palpitations,
headache, pallor, vomiting, weight loss, polyuria, polydipsia, and chest
pain, which may be cardiac in origin. Examination reveals hypertension,
which may be sustained or paroxysmal tachycardia, hypertensive retinopathy,
and possibly signs of ventricular failure caused by dilated cardiomyopathy.
The ECG may reveal dysrhythmia. In childhood, other catecholamine-secreting
tumors, such as neuroblastoma, ganglioneuroblastoma, and ganglioneuroma,
should be considered in the differential diagnosis. The tumor may be defined
by ultrasonography, CT scan, or MRI scan. Laboratory investigations may
reveal a raised hematocrit. Urinary vanillylmandelic acid (VMA) and
metanephrines are elevated, as are plasma catecholamine levels. Extraadrenal
sites of tumor should be excluded by 131metaiodobenzylguanidine (MIBG)
uptake scan. In children, norepinephrine is usually the predominant
catecholamine. In case of metastatic malignant tumor, therapeutic doses of
131I-MIBG are administered.