thoraco-abdominal scan and scintigraphy with iodine 131 mibg are the two tests permitting to demonstrate , with a great sensitivity and specificity , an extra-adrenal localization , which is the best argument in favor of a malignancy since 30 to 40 p. cent of extra-adrenal pheochromocytomas are malignant , more especially as the metastases are located in areas where there are no embryonic remnants of tissues containing chromaffin cells .
C1257877
extra-adrenal pheochromocytomas
C0376604
chromaffin cells