Brief description of the imaging findings in nephroblastoma or Wilms tumor. From Merrow AC Jr. Diagnostic Imaging: Pediatrics. 3rd ed. Elsevier; 2017.

1. Wilms tumor
– imaging findings

2. = nephroblastoma
malignant
in 1-8 years age
commonly < 5 years age

3. large, well-defined
claw sign with the kidney
pseudocapsule – hypo T2

4. heterogeneous
hemorrhage, necrosis, cysts
fibrous septae
Ca++ rare, 15%
hypoenhancing

5. venous invasion – renal vein, IVC, heart cavities
adenopathy
pulmonary metastases

6. look for nephroblastomatosis
assess the other kidney – rare synchronous tumors
if ascites, suspect tumor rupture
pulmonary mets, CXR or CT for staging

7. Remember
large heterogeneous renal mass
with venous invasion in 1-8 years age