[Wilms tumor in hemihypertrophy]

The case of a 4-year-old boy with Wilms' tumor and hemihypertrophy is described. Wilms' tumors are frequently associated with congenital malformations of the urinary tract, with aniridia and hemihypertrophy. Hemihypertrophy is a relatively rare malformation (1:14000) in the common population, but in patients with Wilms' tumors its frequency is about 1:49. Besides Wilms' tumors tumors of the adrenal cortex and hepatoblastomas are frequently observed together with hemihypertrophy.