Abstract

Nephroblastoma is one of the most common tumors of childhood being preceded only bv leukemia and neuroblastoma in frequency. This tumor can be associated with cystic change in or around the tumor. The explanation for these cystic lesions associated with nephroblastoma is still in controversy, although the hypothesis that they are resulted from spontaneous differentiation of the nephroblastoma is more prevailing. Recently we encountered a large tumor in a kidney of a 3 years old girl, which would best be designated as "cystic partially differentiated nephroblastoma".