What are nephroblastomas and other pediatric renal tumors?

Pediatric renal tumors, often detected before the age of five, are among the most common cancers in pediatric oncology.  Among these, nephroblastoma—also known as Wilms tumor—is the most common. It accounts for 90% of pediatric kidney tumors and 5–14% of childhood cancers¹, representing about 100 cases per year in France, around 20 of which are treated at Institut Curie. 

The remaining 10% include various diseases: renal medullary sarcoma, clear cell sarcoma, rhabdoid tumor, mesoblastic nephroma, and Bolande tumor.    

Risk factors for nephroblastoma and pediatric renal tumors

The exact origin of pediatric renal tumors remains unknown, and in the majority of cases they arise randomly.  However, kidney tumors can sometimes develop in a context of genetic predisposition.  Certain genetic diseases are associated with these tumors, such as Beckwith-Wiedermann syndrome and other hypertrophic overgrowth syndromes, or Denys-Drash syndrome. 

Beckwith-Wiedemann syndrome is characterized by fetal overgrowth and hemihypertrophy (i.e., one side of the body more developed than the other). Denys-Drash syndrome is associated with urogenital malformations.

If a child is a carrier of these syndromes, regular clinical monitoring will be carried out to rapidly detect the occurrence of a possible nephroblastoma in this high-risk context, in order to start treatment as soon as possible.
 

[1] Société Française de lutte contre les Cancers et les leucémies de l’Enfant et de l’adolescent.