CT diagnosis of adrenal abnormalities in patients with primary non-adrenal malignancies.

Fifty-seven patients with primary non-adrenal malignancy were found to have unsuspected adrenal abnormality on CT. In 33, comparison of histopathologic findings and/or the patients' hospital course or follow-up lead to the diagnosis of adrenal metastases (23), benign non-functioning adenomas (7), metastasis with hyperplasia (1), benign hyperplasia (1), and fatty infiltration (1). The analysis of CT findings indicated that: I) A heterogeneous adrenal mass showing contrast enhancement was always metastatic, II) Nonfunctioning adenomas were always 3 cm or smaller in diameter, III) Bilateral adrenal masses and growth of adrenal mass on follow-up CT or regression on treatment indicated metastases, and IV) metastatic disease could not be excluded purely on the basis of the size of the adrenal mass.