[Oncocytoma of the kidney. 1. Computed tomography].

The computer tomograms of 22 patients with renal oncocytomas were analysed retrospectively. Characteristic findings were: 1. solid round space-occupying lesions (22/22), 2. sharp demarcation from the kidney (20/22), 3. smooth margin (20/22), 4. hypodensity after intravenous contrast (20/20), 5. enhancement (19/19), 6. central hypodense nidus (16/22), 7. homogeneous beyond the nidus (11/22). In the presence of these criteria, the diagnosis of an oncocytoma may be suspected. Safe differentiation from a renal cell carcinoma may not always be possible.