Staging/Forms 4 (Nephroblastoma)

Preparation of a kidney and of a part of its ureter in a 2.6-year-old boy. Instead of normal kidney tissue, a continuous white-yellowish structure is visible. At the center of the mass there is an area with hemorrhage and disrupted capsule. The final diagnosis is a nephroblastoma in which spontaneously or following a minor trauma a bleeding in the tumor has occurred with rupture of the tumor. This incident leads to 'surgical abdomen' which is in contrast to the leading symptom 'abdominal tumor' a less frequent type of clinical presentation. Likewise, it is important that the tumor stage changes by this incidence to a stage 2 ( II ) or 3 ( III ), with the former being correct when there is a perforation in the retroperitoneum, and the latter when there is a perforation into the peritoneal cavity.