Wilms’ tumor
Description
Malignant mixed tumor of the kidney
Most common intra-abdominal tumor in children; average age at diagnosis is 2 to 4 years
Usually appears on left kidney and is usually unilateral
Remains encapsulated for a long time
Excellent prognosis if metastasis hasn’t occurred
Also called nephroblastoma
Pathophysiology
Embryonal cancer of the kidney originates during fetal life.
In early stages, the tumor is well encapsulated but may later spread into the lymph nodes, renal vein, or vena cava; the tumor may metastasize to the lungs or other sites.
Staging
In stage I, the tumor is limited to one kidney.
In stage II, the tumor extends beyond the kidney but can be completely excised.
In stage III, the tumor has spread but is confined to the abdomen and lymph nodes.
In stage IV, the tumor has metastasized to the lung, liver, bone, and brain.
In stage V, the tumor involves both kidneys.
