Objectives. To compare the radiologic evidence of adrenal involvement on computed tomography (CT) with pathologic reports and to assess the accuracy of CT in the diagnosis of adrenal involvement with renal cell carcinoma.

Methods. Between January 1992 and June 2000, we treated 229 patients with renal cell carcinoma. In this study, we retrospectively analyzed 73 patients who had been examined by CT before surgery and had undergone radical nephrectomy, including removal of the ipsilateral adrenal gland. The abnormal integrity of the adrenal glands on CT and the pathologic adrenal involvement of renal cell carcinoma were demonstrated by a radiologist and pathologist, respectively.

Results. The blinded review by a radiologist of the CT results of 73 patients with renal cell carcinoma identified a normal appearance of the ipsilateral adrenal gland in 54 patients (74%), none of whom had pathologic evidence of malignant involvement. The adrenal gland was diagnosed as abnormal on CT in 19 patients (26%), including enlargement in 7 patients, nodule formation in 7, and an irregular surface in 8. Two of these 19 patients had adrenal involvement. Both were staged at T3M1, and their primary tumors were large, measuring more than 10 cm. In this study, CT demonstrated 100% sensitivity, 76% specificity, 11% positive predictive value, and 100% negative predictive value for ipsilateral adrenal involvement of renal cell carcinoma.

Conclusions. Normal adrenal images on CT could exclude adrenal involvement by renal cell carcinoma. However, radical nephrectomy, including removal of the ipsilateral adrenal gland, should be performed in patients with large tumors.