Wilms Tumor Prognosis

Wilms tumor is the most common type of childhood kidney cancer. It's usually diagnosed in children under 5 but can also affect older kids. With early diagnosis and treatment, patients with Wilms tumor usually have a good prognosis. The great majority can be cured.

Most of the time, the cause of Wilms tumor is unknown. But in about 10% of cases, the condition may result from specific genetic mutations or changes in the activity of certain genes. It's more common in children who have birth defects affecting the urinary system or genitals and in those who are missing an iris (the colored part of the eye) or who have hemihypertrophy (when one side of the body grows larger than the other). There's also increased risk of Wilms tumor among children with certain congenital syndromes, including Beckwith-Wiedemann, Denys-Drash, Frasier and WAGR syndromes.

Although it's less common after childhood, Wilms tumor can affect older adolescents and even adults. Adults with Wilms tumor may discover they have it during treatment for another type of kidney cancer. While the prognosis isn't as positive as for young children, the survival rate for patients ages 15 to 39 is 75%.

Treatment for early-stage Wilms tumor is usually successful. When the cancer hasn't spread, the survival rate is 90%.

What to expect after diagnosis of Wilms tumor

In many cases, treatment begins before a conclusive diagnosis. That's because imaging studies reveal enough information to show that surgery is needed.

After surgery to remove the tumor, a pathologist (a specialist in examining tissues for signs of disease) inspects its cells to confirm the diagnosis of Wills tumor. Sometimes nearby lymph nodes and surrounding tissues are also removed for examination, to learn whether the cancer has spread. How the cells look under the microscope can also indicate whether the cancer has spread or how it may behave. Based on that information, the pathologist will determine the tumor's stage, which will help your child's care team design an appropriate treatment plan.

Treatment for Wilms tumor may include surgery to remove the tumor (typically removing all or at least part of the affected kidney), chemotherapy and radiation therapy. Most patients receive a combination of therapies.

What to expect after treatment of Wilms tumor

Once treatment is completed, your child will have regular follow-up appointments so we can keep a close eye on their health, including by monitoring for any side effects of treatment. Potential long-term complications include:

• Heart failure
• High blood pressure
• Kidney damage
• Secondary cancer elsewhere in the body
• Stunted height

If removal of the cancer significantly affects kidney function or if both kidneys are removed, a kidney transplant may be necessary. Our pediatric Kidney Transplant Program is a leader in the field, with survival rates well above the national average.

As previously noted, when Wilms tumor is diagnosed in an early stage, most kids can be cured, thanks to treatment improvements developed over the past few decades. For relatively nonaggressive cancer that's confined to the kidney, the five-year survival rate is 90% or higher. Even in cases where Wilms tumor has spread beyond the kidney, survival rates range from 60 to 90%, depending on how abnormal the cancer cells are.

The best outcomes are usually in children who:

• Are young
• Have cancer cells whose microscopic appearance is on the lower end of what's considered abnormal
• Have a nonmetastatic tumor (it has not spread)
• Don't have certain gene abnormalities

It is possible for Wilms tumor to come back after treatment. Typically, this occurs within two years of diagnosis. But even if the cancer returns, additional treatment can lead to a cure.