CT demonstration of hyperdense renal carcinoma.

Sharply demarcated homogeneously hyperdense renal lesions have been found to be benign renal cysts, with hemorrhage or a high protein content the most common etiology of the high density. A similar hyperdense renal lesion is presented that was found to be a renal adenocarcinoma. This lesion showed mild contrast enhancement on CT and was found by ultrasound to be a solid mass. The malignant nature of this lesion suggests that further evaluation, such as ultrasound, fine needle aspiration biopsy, or surgery may be needed.