Surgery for Wilms tumour

Most children with Wilms tumour will have surgery. The type of surgery your child has depends mainly on whether the tumour can be removed with surgery. It also depends on whether there are tumours in both kidneys. When planning surgery, the healthcare team will also consider other factors, such as your child’s overall health, if your child has 1 or 2 kidneys and how well the kidneys are working.

Surgery may be done for different reasons. Your child may have surgery to:

• completely remove the tumour
• diagnoseand stage the cancer

The following types of surgery are used to treat Wilms tumour. Your child may also have other treatments before or after surgery.

Before surgery, doctors will use diagnostic tests to find out where the tumour is in the kidney and if it has spread outside the kidney. This usually includes imaging tests such as a CT scan or an MRI. An ultrasound is also commonly used. If imaging tests suggest that there might be cancer in the other kidney, doctors will try to decide whether the tumours can be removed with surgery.

In Canada, most tumours are removed before any chemotherapy is given. In some cases, doctors may decide to give chemotherapy for 6 or more weeks before surgery. They may also take a sample for biopsy. Some of these situations include:

• there are tumours in both kidneys
• the child has only one kidney
• the child has a genetic condition that puts them at risk for kidney failure or to develop more Wilms tumours
• the tumour is very large and has grown beyond the midline (the line that divides the body into right and left halves)
• the tumour has grown deep into the veins of the liver or heart
• the tumour has spread to nearby vital tissues, blood vesselsor organs and these would also have to be removed
• surgery to remove the entire tumour would cause significant or unnecessary damage
• the child is too sick to safely undergo removal

Find out more about CT scans and MRIs.

The most common surgery for Wilms tumour is a radical nephrectomy. A radical nephrectomy removes the entire kidney, including the ureter and surrounding fat and sometimes the adrenal gland. With large tumours, the surgeon may also remove the renal vein.

A partial nephrectomy is also called nephron-sparing surgery. It removes the tumour along with a margin of healthy tissue around it. A partial nephrectomy is only used in certain circumstances as there is a slightly higher chance of recurrence of the tumour. It is typically only used when:

• there are tumours in both kidneys at diagnosis
• the child has only one kidney
• the other kidney is not working well
• the child has a genetic condition that puts them at risk for kidney failure or to develop more Wilms tumours

Knowing if Wilms tumour has spread to the lymph nodes, the other kidney or nearby organs helps the healthcare team determine the stage and further treatment.

During surgery, the surgeon usually makes a surgical cut (incision) in the abdomen and checks the entire abdominal area. This includes close examination of the peritoneum, which is the membrane that lines the walls of the abdomen and pelvis and covers most of the abdominal organs. The surgeon feels the renal vein and inferior vena cava (a large vein that receives blood from lower limbs and organs of the pelvis and abdomen and empties into the right atrium of the heart). The surgeon also examines nearby organs such as the liver. A sample may be taken from any suspicious areas (called a biopsy).

During surgery to remove the tumour, the surgeon removes lymph nodes near the kidney. Surgery to remove the lymph nodes is called a lymph node dissection. Sometimes just a biopsy is done on some of the lymph nodes. Samples from the lymph nodes are examined under a microscope to determine the stage of the cancer. This is very important to do as sometimes cancer may have spread to the lymph nodes without enlarging them.

During a biopsy, the doctor removes tissues or cells from the body so they can be tested in a lab. In most cases of Wilms tumour, it is best to remove the primary tumour without doing a biopsy first. But during surgery, the surgeon may find that the tumour can’t be completely removed. This may occur if the tumour is large and has grown into surrounding tissues and vital blood vessels. The surgeon may take a sample of the kidney for a biopsy, instead of attempting a full removal at that time.

A biopsy may also be done if the child only has one kidney. If both kidneys contain cancer based on imaging tests at diagnosis, a biopsy or nephrectomy is usually delayed until after 6 weeks of chemotherapy.

Surgery may be used to remove cancer that has spread (metastasized) to the liver or lungs or to biopsy an area on the lungs if it showed a spot on imaging. Chemotherapy and radiation therapy are usually given before surgery for metastases. If tumours remain in the liver or lung after these treatments, surgery may be done again to remove them.

Side effects can happen with any type of treatment for Wilms tumour, but every child’s experience is different. Some children have many side effects. Other children have few or none at all.

Side effects can happen any time during, immediately after or a few days or weeks after surgery. Sometimes late side effects develop months or years after surgery. Most side effects will go away on their own or can be treated, but some may last a long time or become permanent.

Side effects of surgery will depend mainly on the type of surgery, effect of other cancer treatments and your child’s overall health.

Surgery for Wilms tumour may cause these side effects:

• scarring
• pain
• nausea and vomiting
• constipation
• trouble urinating
• bleeding
• infection
• bowel obstruction
• lung problems
• kidney failure

Tell your child’s healthcare team if your child has these side effects or others you think might be from surgery. The sooner you tell them of any problems, the sooner they can suggest ways to help your child deal with them.

Find out more about surgery and side effects of surgery. To make the decisions that are right for your child, ask the healthcare team questions about surgery.