Abstract
A 53-year-old woman had a 1.7 cm left adrenal mass on an abdominal computed tomography (CT) scan. She presented with paroxysmal headache, palpitation, sweating, and hypertension. The patient was highly suspected of having a pheochromocytoma, but measurements of 24-hour urinary metanephrine, catecholamines, and vanillylmandelic acid were normal. Plasma and urine catecholamine levels were within the normal range even during paroxysmal episodes. A scintigraphic study with $^{131}I$-metaiodo-benzylguanidine (MIBG) revealed selective concentration of the radiotracer, corresponding to the CT mass. The patient underwent a left adrenalectomy and the pathological examination confirmed the diagnosis of pheochromocytoma. In this report, we describe a rare case of a symptomatic pheochromocytoma with normal catecholamine levels. Our case illustrates that routine nuclear scintigraphy, such as $^{131}I$-MIBG, should be performed even in cases with normal hormonal testing for all patients with high clinical suspicion of pheochromocytoma.
갈색세포종의 특징적인 임상증상을 주소로 내원한 53세 여자 환자에서 혈장과 24시간 소변에서 생화학적 검사는 정상이었지만 MIBG 스캔을 시행하여 복부 CT의 위치와 병변이 일치하는 갈색세포종을 진단하였다. 부신적출술 시행 후 조직학적으로 갈색세포종을 확진했으며 발작적인 증상과 고혈압은 호전되었다. 따라서 카테콜아민치가 정상이더라도 임상증상이 갈색세포종에 합당하다면 핵의학 영상검사가 필요하다고 말할 수 있다.