McAlister W H, Siegel M J, Askin F, Shackelford G D
Radiology. 1979 Aug;132(2):356. doi: 10.1148/132.2.356.
Congenital mesoblastic nephromas are infiltrating tumors that can contain cystic spaces lined with epithelium similar to that of dysplastic tubules and glomeruli. Urographic contrast material may enter these cystic spaces and suggest the diagnosis.