CT diagnosis of renal metastases.

Antemortum detection of renal metastases can be made by computed tomography (CT), particularly if the known primary malignancy is in a late stage. The CT scans of 10 oncologic patients with focal renal metastases were reviewed (confirmation by surgery in four, follow-up CT demonstrating new lesions or lesion growth in two). Five of our cases had only renal metastases and five patients had other areas of metastases. Renal metastases are well circumscribed, rarely enhance, and have density measurements of 25-70 Hounsfield units. Ways of differentiating these lesions from other renal masses are discussed.