Ultrasound Imaging of Cystic Nephroma.

Cystic nephroma is a rare, benign multicystic lesion of the kidney. This tumor occurs both in children and in adults. In children, it is highly prevalent in males; in adults, it is more frequent in women. The term "cystic nephroma" represents two apparently different entities: pediatric cystic nephroma, a benign form thought to originate from metanephric tissue, and adult cystic nephroma, considered as a lesion of mixed epithelial stromal tumor. The clinical presentation may be a palpable mass or nonspecific symptoms such as abdominal pain, hematuria, and urinary tract infections. In this review, we summarize the ultrasound imaging features of cystic nephroma and describe the characteristics of the most common renal cystic lesions and the differential diagnosis of cystic nephroma with other renal cystic lesions.