Wilms Tumor

Wilms tumor, also called nephroblastoma, is the most common kidney cancer in children. It usually affects children aged 3 to 4 and is uncommon after age 6. About 90% of children are cured.

About Wilms tumors

What are Wilms tumors?

Wilms tumor develops from immature kidney cells that did not mature normally before birth. It usually affects one kidney, but in about 5–10% of children both kidneys are involved.

What are the risk factors?

• Some birth differences, such as aniridia (absent iris), hemihypertrophy (one side of the body larger) or undescended testes
• Syndromes such as WAGR, Denys–Drash and Beckwith–Wiedemann syndrome
• A family history of Wilms tumor (rare)

What are the symptoms?

• A painless swelling or lump in the tummy, often noticed by parents during bathing
• Tummy pain
• Blood in the urine
• High blood pressure, fever or loss of appetite

What types of Wilms tumors are there?

• Favourable histology — the great majority, with an excellent outlook
• Anaplastic histology — less common and needs more intensive treatment

Diagnosis confirms that the tumor arises from the kidney, assesses the other kidney and checks for spread.

Medical history and physical exam

Including blood pressure and a search for associated birth differences. The tummy is examined gently to avoid rupturing the tumor.

Ultrasound

Usually the first scan; it also checks the main blood vessels for tumor.

CT

Of the abdomen and chest — shows the tumor, the other kidney and any spread to the lungs.

MRI

An alternative to CT, especially useful when both kidneys are involved.

Chest X-ray

May be used to look for spread to the lungs.

Biopsy

Diagnosis is usually confirmed when the tumor is removed; in some treatment protocols a needle biopsy is done first.

Blood and urine tests

Check kidney function, blood count and clotting.

Wilms tumor is treated by a team of pediatric oncologists, pediatric surgeons and radiation oncologists.

Surgery

Nephrectomy removes the affected kidney together with the tumor. When both kidneys are involved, kidney-sparing surgery (partial nephrectomy) preserves as much healthy kidney as possible.

Chemotherapy

Given before and/or after surgery depending on the protocol, usually with vincristine and actinomycin-D, plus other drugs for higher stages.

Radiation therapy

Needed for higher-stage tumors, anaplastic histology or lung metastases.

Bone marrow / stem cell transplant

High-dose chemotherapy with autologous stem cell rescue is considered for some children with relapsed Wilms tumor.

Targeted therapy

Studied in clinical trials for relapsed and high-risk tumors.

Holistic care

Kidney-function and blood-pressure follow-up, nutrition and family support.

Our pediatric oncologists and surgeons care for children with Wilms tumor.