Wilms Tumor | Diagnosis & Treatment

How is Wilms tumor diagnosed?

The first step in treating your child is forming an accurate and complete diagnosis. Your child’s physician may recommend a number of different tests to determine the cause of the symptoms. In addition to a complete medical history and physical examination, your child’s doctor may order one or more of the following:

After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then we will meet with you and your family to discuss the results and outline the best treatment options.

What are the treatment options for Wilms tumor?

Your child’s physician will determine a specific course of treatment based on several factors, including:

  • your child's age, overall health, and medical history
  • type, location, and size of the tumor
  • extent of the disease (stage)
  • your child's tolerance for specific medications, procedures, or therapies
  • how your child's doctors expect the disease to progress
  • genetic characteristics of the tumor

The first step in Wilms tumor treatment is surgery to remove the tumor. The most common operation is a radical nephrectomy, which removes the whole kidney, the tissue around the kidney, the ureter (the tube that drains urine from the kidney to the bladder), and the adrenal gland (which sits on top of the kidney). This operation is performed if the tumor has occurred in only one kidney. Some cases of low-stage Wilms tumor can be treated with surgery alone.

If your child has bilateral Wilms tumor (tumor in both kidneys) or has a known predisposition to kidney cancer, your child’s physician may recommend a partial nephrectomy or kidney-sparing surgery which aims to remove the tumor while leaving the maximum amount of healthy kidney tissue.

In rare cases — when the tumor is very large — your child’s doctor may recommend chemotherapy to try to shrink the tumor before surgery. In some cases, a biopsy may be the best first surgical procedure for your child, to establish the diagnosis before treatment.

Surgical procedures for Wilms tumor – especially bilateral tumors – should be performed in specialized centers where experienced surgeons, working in the most technologically advanced settings, can provide the most appropriate kidney surgery. Surgeons at Dana-Farber/Boston Children’s have extensive, specialized experience in treating Wilms tumor.

Surgery is usually followed by chemotherapy and sometimes radiation therapy. The type of chemotherapy and need for radiation are determined by tumor stage (extent of spread of the tumor) and tumor type. Radiation therapy may be indicated for some tumors, including any that have spread to the lymph nodes in the abdomen or the lungs.

In very rare cases, a stem cell transplant, involving a transplant of your child’s own stem cells, may be used. This allows your child’s physician to give high-intensity chemotherapy in difficult-to-treat cases of Wilms tumor. Stem cell transplantation and the treatment needed to manage its effects are complex and involve some risk. Your physician will give you more detailed information on what to expect.

Treating other kidney tumors

Malignant rhabdoid tumor of the kidney was once considered a subset of Wilms tumor but is now classified as a separate tumor type in its own right. Other types of kidney tumors include renal cell carcinoma, clear cell sarcoma of the kidney, cystic nephroma, and congenital mesoblastic nephroma.

What is the long-term outlook for children with Wilms tumor?

As with any cancer, prognosis and long-term survival can vary greatly from child to child depending primarily on the stage of the disease and the tumor cells' appearance under a microscope. Prompt medical attention, aggressive therapy, and continued follow-up care are important for the best possible prognosis.

With prompt, aggressive treatment, most children with Wilms tumor are successfully treated and experience relatively few side effects. More aggressive tumors that have spread significantly may be harder to cure. Should a tumor come back after treatment, your doctor may recommend additional surgery, chemotherapy, and/or radiation therapy.

The goal of treatment is both to cure the cancer and minimize the long-term effects of therapy. Children, however, are at some risk of late-effects of the cancer and its treatment, including high blood pressure, heart and lung problems after chemotherapy or radiation therapy, and slowed or decreased growth and development. Reduced kidney function may appear primarily in children with tumors in both kidneys (bilateral involvement) or with a predisposition syndrome that causes kidney abnormalities (nephritis) distinct from those related to the tumor or treatment.

Factors that influence the outlook for a child with Wilms tumor include:

  • extent of the disease
  • the histology of the tumor (what it looks like under the microscope)
  • genetic changes in the tumor
  • age and overall health of the child at diagnosis
  • size of the primary tumor
  • response to therapy
  • your child's tolerance of specific medications, procedures, or therapies