Sonographic Diagnosis of an Unusual Case of Multilocular Cystic Nephroma Mimicking Polycystic Kidney Disease

Abstract

The following is a report of the unusual case of a multilocular cystic nephroma in an 8-year-old boy who was transferred to our unit with a palpable abdominal tumor. The patient suffered from thoracic pain and night sweating. The laboratory values were normal. Abdominal sonography showed a huge kidney tumor on the right side consisting of numerous small cysts transversed by irregular septa of variable thickness. The cysts had a diameter of 1 -5 mm; larger cysts of more than 1 cm in diameter were not able to be shown. In the center of the tumor a normal renal parenchyma was able to be shown. The tumor arose like a mushroom from the kidney. Color Doppler sonography showed good vascularity of the normal renal parenchyma while the tumor had only a few internal vessels. The tumor was surgically removed. The histologic diagnosis was cystic nephroma. Unusual features of this tumor were the small size of the numerous cysts similar to polycystic kidney disease and the mushroom-like growth of the tumor.

Prenatal sonographic diagnosis of multicystic congenital mesoblastic nephroma

“…Cystic nephroma is characterized by large multiple non‐communicating cysts which are lined by cuboidal or flattened epithelial cells and partitioned by septa . In multicystic dysplasia, round‐ or oval‐shaped non‐communicating cysts replace the entire kidney . Both entities are distinguishable from CMN by the absence of solid elements other than septa .…”

“…In multicystic dysplasia, round‐ or oval‐shaped non‐communicating cysts replace the entire kidney . Both entities are distinguishable from CMN by the absence of solid elements other than septa . Also, cystic nephroma is usually seen in children between 2 and 4 years of age .…”