[Differential diagnosis between nonhyperfunctioning adenoma and adrenal metastasis on adrenocortical scintigraphy]

Adrenocortical scintigraphy using I-131-adosterol was performed in six cases of nonhyperfunctioning adenoma incidentally discovered on CT scans and four cases of adrenal metastasis. In all six cases of nonhyperfunctioning adenoma, there was increased uptake of of the I-131-adosterol on the side of the adrenal mass discovered at CT. In three of four cases of adrenal metastasis, there was no uptake of the I-131-adosterol on the side of the mass detected at CT. Uptake was symmetrical in one case of adrenal metastasis. Adrenocortical scintigraphy is able to differentiate nonhyperfunctioning adenoma from adrenal metastasis in recognition of increased uptake of I-131-adosterol on the side of the adrenal mass discovered on CT scans.