paediatrics Brussels 17

Anaplastic Wilms’ Tumor

• Unfavorable histology found in 4 to 5% of NWTS and SIOP studies • Uncommon in infants, but found in about 10% of patients > 5 years of age • Anaplasia refers to significant enlargement of nuclei in stromal, blastemal or epithelial components to at least 3X, hyperchromatism of enlarged nuclei and multiple mitotic figures