초록
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.
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.