Transient Enhanced Uptake of 123I-Metaiodobenzylguanidine in the Contralateral Adrenal Region after Resection of an Adrenal Pheochromocytoma

To the Editor: Pheochromocytomas are tumors of chromaffin tissue that may secrete catecholamines continuously or intermittently, thereby causing sustained or paroxysmal hypertension, respectively. After removal of the primary tumor, 6 to 23 percent of patients may have recurrences, and follow-up is therefore essential. 1 The tests used for this purpose include measurements of 24-hour urinary catecholamine secretion and the clonidine suppression test. A specific method for detecting chromaffin in tumors is 123 I-metaiodobenzylguanidine ( 123 I-MIBG) scintigraphy. 2 In vitro experiments suggest that MIBG accumulates in adrenergic tissue by means of the norepinephrine-uptake transporter. 3 We describe a patient with a pheochromocytoma in whom 123 I-MIBG . . .