[Radiological studies in the preoperative diagnosis of cystic cystadenoma of the kidney].

Investigations in 7 patients with cystadenoma (5 cases) or cystadenocarcinoma (2 cases) of kidney included intravenous urography, ultrasonography, arteriography and in 4 cases, computed tomography imaging. All these examinations, and particularly ultrasound imaging, provided strongly suggestive evidence of the diagnosis, as seen on images as a single parenchymatous mass constituted of "cystic" formations separated by partitions of variable thickness. Possible differential diagnosis includes necrotic cancer, hydatid or blood-containing cysts. Unfortunately, these different imaging techniques fail to distinguish between thick wall cystadenoma and cystadenocarcinoma, positive diagnosis requiring histology. Preoperative recognition of cystadenoma allows initial conservative surgery to be performed, followed by secondary operation if histology reserves an unpleasant surprise.