Treatments and drugsBy Mayo Clinic staff
Standard treatment for Wilms' tumor is surgery and chemotherapy. The stage of the tumor and appearance of the cancer cells under a microscope help determine whether your child also needs radiation therapy. At this point, your doctor may tell you the tumor appears to be either favorable or unfavorable (anaplastic) — the histology of the tissue. Children whose tumors have a favorable histology have better survival rates. However, many children with unfavorable histology also have good outcomes.
Because this type of cancer is rare, your doctor may recommend that you seek treatment at a children's cancer center that has experience treating this type of cancer.
Surgical removal of kidney tissue is called nephrectomy. The various types of nephrectomy include:
- Simple nephrectomy. In this surgery, the surgeon removes the entire kidney. The remaining kidney can increase its capacity and take over the entire job of filtering the blood.
- Partial nephrectomy. This involves removal of the tumor and part of the kidney tissue surrounding it. It's usually performed when the other kidney is damaged or has already been removed.
- Radical nephrectomy. In this type of surgery, doctors remove the kidney and surrounding tissues, including the ureter and adrenal gland. Neighboring lymph nodes also may be removed.
At surgery, your child's doctor may examine both kidneys and the abdominal cavity for evidence of cancer. Samples from the kidney, lymph nodes and any tissues that appear abnormal are removed and examined by microscope to identify cancer cells.
If both kidneys need to be removed, your child will need dialysis until he or she is healthy enough for a transplant.
A doctor specializing in pathology examines your child's tumor cells under a microscope and looks for features that indicate whether the cancer is aggressive or is susceptible to chemotherapy.
Chemotherapy uses medication to kill cancer cells throughout the body. This treatment affects rapidly dividing cells; thus, normal cells with fast turnover — such as hair follicles, cells in the gastrointestinal tract and bone marrow, the tissue at the core of bone that manufactures blood cells — are affected as well as cancer cells. As a result, these medications can have the side effects of nausea, vomiting, loss of appetite, hair loss and low white blood cell counts. Most side effects will improve after the drug is stopped, and some may lessen during therapy. Ask your child's doctor what side effects may occur during treatment, and if there are any potential long-term complications.
At high doses, chemotherapy can destroy bone marrow cells. Although it's not usually standard treatment, if your child is to undergo high-dose chemotherapy, your child's doctor may suggest that marrow cells be removed in advance and frozen. After chemotherapy, the marrow will be returned through an intravenous line, a procedure called autologous bone marrow reinfusion.
Radiation therapy uses X-rays or other sources of high-energy rays to kill cancer cells. It's usually started within a few days after surgery. If your child is very young, he or she may need a sedative to remain still during treatment. A doctor specializing in radiation therapy will mark the area to be treated with a special dye. Areas that should not receive radiation are shielded. Possible side effects include nausea, fatigue and skin irritation. Diarrhea may occur after radiation to the abdomen — ask your doctor to suggest an over-the-counter or prescription medication for relief.
Treatment regimens by stage
The treatment your child undergoes depends on the stage of the cancer, the type of cancer cell, and the child's age and general health.
- Stage I or II cancer. If the cancer is restricted to the kidney or nearby structures — and the cell type is not aggressive, your child will undergo removal of the affected kidney and tissues and some of the lymph nodes near the kidney, followed by chemotherapy. Some stage II cancers are also treated with radiation.
- Stage III or IV cancer. If the cancer has spread within the abdomen and can't be completely removed without jeopardizing structures such as major blood vessels — radiation will be added to surgery and chemotherapy. Your child may undergo chemotherapy before surgery to shrink the tumor.
- Stage V cancer. If the tumor cells are in both kidneys — part of the cancer from both kidneys will be removed during surgery and neighboring lymph nodes taken to see if they contain tumor cells. Chemotherapy is used to shrink the remaining tumor. Surgery is repeated to remove as much tumor as possible while leaving functioning kidney tissue. More chemotherapy and radiation therapy may follow.
Children react differently to therapies, so adjustments may be necessary. Discuss your child's treatment plan with his or her doctor and make certain that you understand the benefits and risks before giving your consent. Ask the doctor about side effects of treatments and when to report them, and what can be done to ease them.
Your child's prognosis depends on the stage and cell type of the tumor.
Considering a clinical trial
Your child will receive the best care at a major medical center whose staff has expertise in treating this form of cancer. Your child's regular doctor can arrange a referral.
Because advances in treating children with Wilms' tumor have come through research, you may be asked to consider letting your child participate in a clinical trial, a carefully planned study to evaluate the benefits and risks of experimental treatments. Researchers must give you all of the available information about the trial before asking you to sign consent forms. Many children with cancer are treated in a clinical trial at some point in their illness. However, enrollment in a clinical trial is up to you and your child. Talk to your child's doctor to find out more about clinical trials.
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