Adrenal localization in the adrenocorticotropic hormone-independent Cushing syndrome.
OBJECTIVE
To assess the efficacy of 131I-6-beta-iodomethylnorcholesterol scintigraphy in the adrenocorticotropic hormone-independent Cushing syndrome and to compare this with computed tomography.


METHODS
Retrospective analysis of case series from 1977 to 1987.


METHODS
Referral to the Division of Nuclear Medicine at a tertiary-care university medical center.


METHODS
Twenty-four patients with a pathologically-confirmed diagnosis of the adrenocorticotropic hormone-independent Cushing syndrome had 131I-6-beta-iodomethylnorcholesterol scintigraphy and, in most cases, computed tomography.


RESULTS
Using 131I-6-beta-iodomethylnorcholesterol scintigraphy, adenomas were accurately seen as focal, unilateral tracer uptake in 14 of 14 patients. In carcinoma, the classic scintigraphic pattern of bilateral nonvisualization was observed in 3 of 4 patients, with ipsilateral uptake of tracer in 1 patient with a histologically well-differentiated malignancy. Computed tomography done during the same interval depicted abnormal adrenals in all cases of adenoma and carcinoma. In cortical nodular hyperplasia, however, computed tomography identified abnormal pairs of adrenals in only one of four cases studied, whereas scintigraphy showed typical patterns of bilateral increased uptake in all of the cases.


CONCLUSIONS
131I-6-beta-iodomethylnorcholesterol scintigraphy accurately shows the location and nature of adrenal dysfunction in the adrenocorticotropic hormone-independent Cushing syndrome and may be particularly useful in identifying the bilateral adrenal involvement in cortical nodular hyperplasia.
Fig
L M
LM
University of Michigan, Ann Arbor.
Gross
M D
MD
Shapiro
B
B
Ehrmann
D A
DA
Freitas
J E
JE
Schteingart
D E
DE
Glazer
G M
GM
Francis
I R
IR
D015071:19-Iodocholesterol / Q000031:analogs & derivatives*; D000236:Adenoma / Q000175:diagnosis; D000302:Adrenal Cortex / Q000000981:diagnostic imaging* / Q000473:pathology; D000303:Adrenal Cortex Diseases / Q000150:complications / Q000175:diagnosis*; D000306:Adrenal Cortex Neoplasms / Q000175:diagnosis; D002277:Carcinoma / Q000175:diagnosis; D002784:Cholesterol / Q000031:analogs & derivatives*; D003480:Cushing Syndrome / Q000000981:diagnostic imaging* / Q000209:etiology; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000175:diagnosis; D007457:Iodine Radioisotopes; D008297:Male; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
D007457:Iodine Radioisotopes; D015071:19-Iodocholesterol; C035501:6-iodomethylcholesterol; D002784:Cholesterol