Surgery for Wilms tumors
Surgery is the main treatment for nearly all children with Wilms tumor. It should be done by a surgeon who specializes in operating on children and has experience in treating these cancers.
Removing the tumor
The main goal of surgery is to remove the Wilms tumor. A major concern during the operation is to try to remove the entire tumor in one piece to prevent the possible spread of cancer cells within the abdomen. Surgeons who operate on these tumors are careful to limit the chance of this type of cancer spread whenever possible. If the surgeon finds (either with imaging tests done before surgery, or upon starting the operation) that the entire tumor can’t be removed safely, other treatments may be used. If these treatments shrink the tumor enough, surgery can then be done more safely.
Depending on the situation, different operations may be used.
Radical nephrectomy: This is the most common operation for Wilms tumor that is only in one kidney, as it provides the best chance of making sure all of the tumor is removed. During this procedure, the surgeon makes an incision (usually down the middle of the abdomen) and removes the cancer along with the whole kidney, the fatty tissue around the kidney, the ureter (tube that carries urine from the kidney to the bladder), and the attached adrenal gland (a hormone-making gland that sits on top of the kidney). Most children can live very well with only one kidney.
Partial nephrectomy (nephron-sparing surgery): In the small number of children who have Wilms tumors in both kidneys, the surgeon will try to save some normal kidney tissue, if possible. The surgeon may remove the kidney containing the most tumor with a radical nephrectomy. In the other kidney the surgeon may do a partial nephrectomy, which removes just the tumor and a margin of normal kidney around it. Another option may be to do partial nephrectomies in both kidneys.
Sometimes, both kidneys may need to be removed completely. The child will then need dialysis several times a week. In this procedure, a machine does the job of the kidneys by filtering waste products out of the blood. Once the child is healthy enough, a kidney transplant may be an option if a donor kidney becomes available.
Assessing the extent of the disease (surgical exploration)
Another main goal of the operation to remove the tumor (radical or partial nephrectomy) is to determine the extent of the cancer and whether or not it can all be removed. Lymph nodes near the kidney will also be removed to look for cancer cells in them. (Lymph nodes are bean-sized collections of immune cells to which cancer often spreads.) Lymph node removal is known as a regional lymphadenectomy.
The other kidney and nearby organs such as the liver may also be looked at closely, and any suspicious areas biopsied (samples taken to be looked at under a microscope).
Knowing if a Wilms tumor has spread to the lymph nodes, the other kidney, or other nearby organs is important in determining its stage and further treatment options.
Placing a central venous access line or device (port)
Often, if the child is going to get chemotherapy, a surgeon will insert a small plastic tube called a catheter into a large blood vessel – usually under the collar bone. This tube may be called a venous access line, venous access device, central venous catheter, or just a port. The end of the tube will be just under the skin or sticking out of the chest area or upper arm. This can be left in place for several months to take blood samples for tests and to give intravenous (IV) chemotherapy drugs and blood transfusions, without needing to puncture the skin in the arm each time. Members of the cancer care team will teach you how to care for your child's venous access device to reduce the risk of problems such as infections.
Possible risks and side effects of surgery
Surgery to remove a Wilms tumor is a serious operation, and surgeons are very careful to try to limit any problems either during or after surgery. Complications during surgery such as bleeding, injuries to major blood vessels or other organs, or reactions to anesthesia are rare, but they can happen.
Almost all children will have some pain for a while after the operation, although this can usually be helped with medicines if needed. Other problems after surgery are uncommon but can include internal bleeding, infections, or problems with food moving through the intestines.
If there are tumors in both kidneys, another concern is the loss of kidney function. In these cases, doctors must balance between making sure the tumors are removed completely and removing only as much tissue as is needed. Children who have all or parts of both kidneys removed may need dialysis, and may eventually need a kidney transplant.
For more information on surgery as a treatment for cancer, see the separate American Cancer Society document, Surgery.
Last Medical Review: 07/27/2012
Last Revised: 01/17/2013