Nephrogenic metaplasia of urinary tract in children: report of three cases and review of the literature.

Nephrogenic metaplasia of the urinary tract, originally thought to be a benign tumor with possible malignant potential, is commonly called nephrogenic adenoma. It predominantly affects male adults and is rarely seen in children. In this report 18 pediatric cases are reviewed and some clinical and pathologic parameters are compared with the condition in adults. Male to female ratio is reversed (3.7:1 in adults and 1:3.5 in children). Recurrences are more common and are more frequently multiple in the pediatric age group. Although no malignant transformation has been reported, prolonged follow-up is recommended since the natural history of this lesion is still uncertain.