Published: Aug. 26, 2011
Updated: Aug. 26, 2011
Wilms tumors are cancerous tumors that form in the kidneys. They are the most common type of kidney cancer in children and rarely form in children older than age six.
Wilms tumors can spread to the lungs, liver, or lymph nodes. The outlook for patients depends on whether the tumor or tumors can be completely removed, the age of the child, and the stage of the tumor.
Symptoms vary depending on the type of cancer. Many of the symptoms of childhood cancers can also be symptoms of other diseases. Be sure to consult your doctor if your child has symptoms that seem unusual for him or her.
Below are symptoms that often occur with Wilms tumors:
In addition to being divided into four stages, Wilms tumors are classified according to how they appear under the microscope (their histology).
Tumors with a favorable histology respond better to chemotherapy and have a better outlook than those classified as anaplastic, which have cells that are of abnormal shape and size. Most Wilms tumors are classified as favorable.
The four stages of Wilms tumors are:
There is also a special designation for Wilms tumor that affects both kidneys:
Surgery, chemotherapy, and radiation therapy are the standard treatments for many childhood cancers. Your child may receive one or more treatments depending on the stage or grade of the cancer, your child’s general health, and other factors.
Surgery is the main treatment for Wilms tumor. In most cases, the tumor is in only one kidney, so the kidney may be removed. If there are tumors in both kidneys, only a portion of the kidney or kidneys may be removed.
If both kidneys must be removed, the child will need to have dialysis (a procedure in which a machine removes waste products from the blood) until a kidney transplant can be performed.
Chemotherapy, radiation, or both may also be used after surgery to kill any remaining cancer cells. Children with larger stage tumors may undergo chemotherapy before surgery to shrink the tumor.