Presacral Extrarenal Wilms Tumor in a Child

OBJECTIVES Wilms tumor (WT) is one of the most common solid tumors in children. It also is the most frequent tumor found in the kidneys. In 5% of cases, it affects both kidneys Simultaneously. Extrarenal. WTs are extremely rare. The diagnosis of extrarenal WT is almost always made after Surgical intervention. The tumor can be located in the retroperitoneum, uterus, cervix, testes, skin, and even the thorax. METHODS We report on a 3-year-old girl with an extrarenal WT located in the presacral region. RESULTS The exact mechanism whereby a WT occurs in extrarenal tissues is unknown. The presence of ectopic metanephric blastema cells or the WT gene causing transformation of extrarenal primitive mesonephric or pronephric remnants into WT have both been considered in the embryogenesis. Although imaging examinations are helpful in the definition of retroperitoneal tumors, no characteristic findings are available to diagnose an extrarenal WT before surgery. CONCLUSIONS As a rule, the diagnosis of extrarenal WT is made after Surgery. Surgical excision is the treatment of choice and the same general therapeutic rules should be followed as when the kidney has been affected. The use of Stage III guidelines for chemotherapy and radiotherapy are appropriate for these patients. UROLOGY 74: 308-310, 2009. (C) 2009 Elsevier Inc.