Unusual Visualization of an Adrenal Carcinoma on NP-59 Scintiscan

[Iodine-131]6-beta-iodomethylnorcholesterol (NP-59) visualization of adrenocortical carcinoma is unusual. We describe a 17-year-old female with virilization and elevated plasma testosterone, dehydroepiandrosterone sulfate (DHEAS) and aldosterone. Magnetic resonance imaging disclosed a 9-cm right adrenal mass. NP-59 adrenal scanning displayed unilateral uptake of tracer and no visualization of the contralateral adrenal gland. Exploratory laparotomy revealed adrenocortical carcinoma. Subsequent immunohistochemical studies confirmed that the tumor was capable of producing a mixture of steroids, including testosterone, DHEAS and aldosterone. Visualization of an adrenal tumor on NP-59 scintiscan is an unusual finding, which cannot exclude the possibility of malignancy.