A Wilms tumor is a malignant tumor in the kidneys. This disease mainly occurs in children between 1 and 5 years old. Depending on the stage of the disease, treatment lasts from several months to six months. The disease is more common in girls than in boys. Fortunately, the chance of recovery from this disease is relatively high.

What is a Wilms tumor?

A Wilms tumor is also known as Nephroblastoma. Nephro involves the kidney, and blastoma is the type of cells from which the tumor arises. The name Wilms tumor comes from the German surgeon Max Wilms, who lived in the nineteenth century.A Wilms tumor originates from the kidneys. In the early stages, the disease is often difficult to detect, because the tumor is then limited to the inside of the kidney. In later stages, the tumor may grow larger, making it visible even from the outside. The disease can also spread to other organs.In almost three quarters of all cases, this disease occurs in children under five years old. Approximately twenty cases of a Wilms tumor are known in the Netherlands each year. The disease is slightly more common in children of black descent, and occurs slightly more often in girls than in boys. It is not known what the causes of this are.Children born with Beckwith Wiedemann syndrome or WAGR syndrome have an increased risk of developing a Wilms tumor. For this reason, these children regularly receive an abdominal ultrasound.

What are the symptoms?

A Wilms tumor can continue to grow for a very long time without causing complaints. It often only becomes clear when a bulge is visible in the abdomen. Sometimes this manifests itself in a very bulging abdomen, but in other cases it is a bump that is only palpable in the flanks. In some cases the child will complain of abdominal pain or a strange feeling in the abdomen. There may also sometimes be some blood in the urine.If a Wilms tumor is suspected, an ultrasound scan of the abdomen will be required to confirm this . A urine test is also done. This way it can be ruled out that it is a different type of tumor than a Wilms tumor.

The treatment

A Wilms tumor will initially be treated with chemotherapy. This is done to shrink the tumor. Often the tumor does not disappear completely due to chemotherapy. This is followed by surgery. If the tumor has not disappeared due to chemotherapy, the entire kidney will be removed during this operation. After the kidney is removed, chemotherapy or radiation will be administered again. how long this is necessary depends on the stage of the disease.Removing the kidney has no further consequences. The function of the kidneys is immediately taken over by the one remaining kidney. In some cases, the disease occurs in both kidneys. If both kidneys need to be removed, a donor kidney is needed for the patient.Fortunately, this type of cancer is quite curable. 70 to 90% of all cases can be completely cured. Of course, this percentage depends on the stage of the disease. When the disease has spread further, the chance of recovery is smaller. However, even with a metastatic Wilms tumor, the chance of cure is still 70%.