RESUMO
Pheochromocytomas account for less than one percent of hypertension and are usually suspected because of clinical manifestations, confirmed by laboratory evaluation and subsequently localized by radiology. Higher HU units on pre-contrast CT and hyperintense signal on T2 weighted MRI images are often seen in pheochromocytoma. Metaiodobenzylguanidine (MIBG) scans have been widely used to localize pheochromocytoma and false-positive scans are reported to be rare. We report a hypertensive patient with symptoms consistent with a pheochromocytoma, with a left adrenal mass with a pre-contrast HU of 8 but a 70 HU post-contrast value. No biochemical evidence of catecholamine excess was noted. A MIBG scan was reported as highly suspicious for a pheochromocytoma. Laparoscopic resection of the mass confirmed the presence of a peri-adrenal hemangioma with both capillary and cavernous components. We postulate that the accumulation of MIBG because of the hemangioma was responsible for the false-positive MIBG scan.
