Adrenal scintigraphy with 131I-19-iodochlesterol in the diagnosis of Cushing's syndrome associated with adrenal tumor.

Seven patients with Cushing's syndrome secondary to adrenocortical tumors were studied using 131I-19-iodocholesterol. The diagnosis of all cases were verified histologically. In three cases with adenoma the uptake of the tracer was in the tumor only, while the two patients with adrenocortical carcinoma failed to show adrenal accumulation of the labelled compound. In two patients there was a hyperplasia-like scintigraphic pattern, while the stimulation and suppression biochemical tests suggested adrenal tumor. One of these cases was verified as a mixed form (adenoma plus hyperplasia), and the tumor bearing gland was significantly larger on the scan which helped the preoperative localization. In the other case, verified as bilateral multiple adrenocortical adenomas, the autonomus function of both adrenals was proved by dexamethasone suppression scanning. It seens reasonable to use the latter as an adunctive diagnostic procedure in patients where there is a discrepancy between the standart scintiscan and the biochemical indexes of adrenal hyperfunction.