Wilms’ Tumor

Also known as: Wilms tumor, nephroblastoma.

What is Wilms tumor?

Wilms tumor is a rare type of cancer that starts in the kidney and occurs most often in children ages 3 or 4. The cancer usually affects one of the two kidneys, though it can occur in both at the same time. There are 2 major types of Wilms tumor based on how they look under the microscope. Most have cells that give children a good chance of being cured.

What causes Wilms tumor?

There appears to be a cell mutation (an error) that leads to the development of a Wilms tumor, though the reason that this occurs is not clear. In a small number of families the mutations are genetic and are passed from parent to child.

What are the signs and symptoms of nephroblastoma?

Wilms tumor typically does not cause any symptoms at all until it is quite large. At that point, children may experience abdominal pain, a swollen or heavy abdomen, blood in the urine and fever.

What are Wilms' tumor care options?

Surgery to remove Wilms’ tumor is the primary treatment option. Depending on the size of the tumor, this surgery may involve removing all or part of the affected kidney.

Chemotherapy and radiation therapy are also used in the treatment of Wilms tumor. Chemotherapy may be used before surgery to shrink the tumor, or afterward to kill any cancer that has spread to other parts of the body.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: April 07, 2022 02:38 PM

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