Wilms Tumor

  • Etiology: renal origin, 30% of unilateral and 100% of bilateral Wilms tumor are due to nephrogenic rests
  • Imaging: claw sign, deforms the collecting system showing it is an intrarenal mass, pushing tumor that displaces vessels, 10% are calcified
  • Complications: renal vein / inferior vena cava tumor thrombus, involves contralateral kidney either synchronous or metachronous in 10%, metastasis to lung, bone, liver
  • Clinical: associated with Beckwith-Wiedemann syndrome

Cases of Wilms Tumor

Gross pathological image of Wilms tumor
Gross pathological image shows a whitish-tan mass with areas of hemorrhage and necrosis arising from the lower pole of the kidney . Note the compression of the adjacent renal tissue which manifests itself on imaging as the renal “claw” sign.