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.