General Information About Wilms Tumor and Other Childhood Kidney Tumors

Childhood kidney tumors are diseases in which malignant (cancer) cells form in the tissues of the kidney.

There are two kidneys, one on each side of the spine, above the waist. Tiny tubules in the kidneys filter and clean the blood. They take out waste products and make urine. The urine passes from each kidney through a long tube called a ureter into the bladder. The bladder holds the urine until it passes through the urethra and leaves the body.
Anatomy of the urinary system showing the kidneys, ureters, bladder, and urethra. The inside of the left kidney shows the renal pelvis. An inset shows the renal tubules and urine. Also shown is the spine and adrenal glands. Urine is made in the renal tubules and collects in the renal pelvis of each kidney. The urine flows from the kidneys through the ureters to the bladder. The urine is stored in the bladder until it leaves the body through the urethra.

There are many types of childhood kidney tumors.

Wilms Tumor

In Wilms tumor, one or more tumors may be found in one or both kidneys. Wilms tumor may spread to the lungs, liver, bone, brain, or nearby lymph nodes. In children and adolescents younger than 15 years old, most kidney cancers are Wilms tumors.

Renal Cell Cancer (RCC)

Renal cell cancer is rare in children and adolescents younger than 15 years old. It is much more common in adolescents between 15 and 19 years old. Children and adolescents are more likely to be diagnosed with a large renal cell tumor or cancer that has spread. Renal cell cancers may spread to the lungs, liver, bone, or lymph nodes. Renal cell cancer may also be called renal cell carcinoma.

Rhabdoid Tumor of the Kidney

Rhabdoid tumor of the kidney is a type of kidney cancer that occurs mostly in infants and young children. It is often advanced at the time of diagnosis. Rhabdoid tumor of the kidney grows and spreads quickly, often to the lungs or brain.

Children with a certain change in the SMARCB1gene can also have tumors grow in the kidney, brain, or soft tissues. These children are checked regularly to see if a rhabdoid tumor has formed in the kidney or the brain:

• Children from birth or diagnosis to 5 years old have an MRI of the brain and spine and an ultrasound of the abdomen every 3 months.

Clear Cell Sarcoma of the Kidney

Clear cell sarcoma of the kidney is an uncommon kidney cancer that may spread to the bone, lungs, brain, liver, or soft tissue. It occurs most often before age 3 years. It may recur (come back) up to 14 years after treatment, often in the brain or lung.

Congenital Mesoblastic Nephroma

Congenital mesoblastic nephroma is a tumor of the kidney that is often diagnosed during the first year of life or before birth. It is the most common kidney tumor found in infants younger than 6 months old and is found more often in males than in females. It can usually be cured.

Ewing Sarcoma of the Kidney

Ewing sarcoma (previously called neuroepithelial tumor) of the kidney is rare and usually occurs in young adults. This cancer grows and spreads to other parts of the body quickly.

Primary Renal Myoepithelial Carcinoma

Primary renal myoepithelial carcinoma is a rare type of cancer that usually affects soft tissues, but sometimes forms in the internal organs (such as the kidney). This type of cancer grows and spreads quickly.

Cystic Partially Differentiated Nephroblastoma

Cystic partially differentiated nephroblastoma is a very rare type of Wilms tumor made up of cysts.

Multilocular Cystic Nephroma

Multilocular cystic nephromas are benign tumors made up of cysts and are most common in infants, young children, and adult women. These tumors can occur in one or both kidneys.

Children with this type of tumor also may have pleuropulmonary blastoma, so imaging tests that check the lungs for cysts or solid tumors are done. Since multilocular cystic nephroma may be an inherited condition, genetic counseling and genetic testing may be considered. See the PDQ summary about Childhood Pleuropulmonary Blastoma Treatment for more information.

Primary Renal Synovial Sarcoma

Primary renal synovial sarcoma is a cyst-like tumor of the kidney and is most common in young adults. These tumors grow and spread quickly.

Anaplastic Sarcoma of the Kidney

Anaplastic sarcoma of the kidney is a rare tumor that is most common in children or adolescents younger than 15 years of age. Anaplastic sarcoma of the kidney often spreads to the lungs, liver, or bones. Imaging tests that check the lungs for cysts or solid tumors may be done. Since anaplastic sarcoma may be an inherited condition, genetic counseling and genetic testing may be considered.

Nephroblastomatosis is not cancer but may become Wilms tumor.

Sometimes, after the kidneys form in the fetus, abnormal groups of kidney cells remain in one or both kidneys. In nephroblastomatosis (diffuse hyperplastic perilobar nephroblastomatosis), these abnormal groups of cells may grow in many places inside the kidney or make a thick layer around the kidney. When these groups of abnormal cells are found in a kidney after it was removed for Wilms tumor, the child has an increased risk of Wilms tumor in the other kidney. Frequent follow-up testing is important at least every 3 months, for at least 7 years after the child is diagnosed or treated.

Having certain genetic syndromes, other conditions, or environmental exposures can increase the risk of Wilms tumor.

Anything that increases the risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk to your child's doctor if you think your child may be at risk.

Wilms tumor may be part of a genetic syndrome that affects growth or development. A genetic syndrome is a set of signs and symptoms or conditions that occur together and is caused by certain changes in the genes. Certain conditions or environmental exposures can also increase a child's risk of developing Wilms tumor. The following have been linked to Wilms tumor:

• WAGR syndrome (Wilms tumor, aniridia, abnormal genitourinary system, and mental disability).
• Denys-Drash syndrome (abnormal genitourinary system).
• Frasier syndrome (abnormal genitourinary system).
• Beckwith-Wiedemann syndrome (abnormally large growth of one or more body parts, large tongue, umbilical hernia at birth, and abnormal genitourinary system).
• A family history of Wilms tumor.
• Aniridia (part or all of the iris, the colored part of the eye, is missing).
• Isolated hemihyperplasia (abnormally large growth of one or more body parts).
• Urinary tract problems such as cryptorchidism or hypospadias.
• The child's mother being exposed to pesticides while she was pregnant.

Tests are used to screen for Wilms tumor.

Screening tests are done in children with an increased risk of Wilms tumor. These tests may help find cancer early and decrease the chance of dying from cancer.

In general, children with an increased risk of Wilms tumor should be screened for Wilms tumor every 3 months until they are at least 8 years old. An ultrasound test of the abdomen is usually used for screening. Small Wilms tumors may be found and removed before symptoms occur.

Children with Beckwith-Wiedemann syndrome or hemihyperplasia are also screened for liver and adrenal tumors that are linked to these genetic syndromes. A test to check the alpha-fetoprotein (AFP) level in the blood and an ultrasound of the abdomen are done until the child is 4 years old. An ultrasound of the kidneys is done between the ages of 4 and 7 years old. A physical exam by a specialist (geneticist or pediatric oncologist) is done two times each year. In children with certain gene changes, a different schedule for ultrasound of the abdomen may be used.

Children with aniridia and a certain gene change are screened for Wilms tumor every 3 months until they are 8 years old. An ultrasound test of the abdomen is used for screening.

Some children develop Wilms tumor in both kidneys. These often appear when Wilms tumor is first diagnosed, but Wilms tumor may also occur in the second kidney after the child is successfully treated for Wilms tumor in one kidney. Children with an increased risk of a second Wilms tumor in the other kidney should be screened for Wilms tumor every 3 months for up to 8 years. An ultrasound test of the abdomen may be used for screening.

Having certain conditions may increase the risk of renal cell cancer.

Renal cell cancer may be related to the following conditions:

• Von Hippel-Lindau disease (an inherited condition that causes abnormal growth of blood vessels). Children with Von Hippel-Lindau disease should be checked yearly for renal cell cancer with an ultrasound of the abdomen or an MRI (magnetic resonance imaging) beginning at age 8 to 11 years.
• Tuberous sclerosis (an inherited disease marked by noncancerous fatty cysts in the kidney).
• Familial renal cell cancer (an inherited condition that occurs when certain changes in the genes that cause kidney cancer are passed down from the parent to the child).
• Renal medullary cancer (a rare kidney cancer that grows and spreads quickly).
• Hereditary leiomyomatosis (an inherited disorder that increases the risk of having cancer of the kidney, skin, and uterus).

Prior chemotherapy or radiation therapy for a childhood cancer, such as neuroblastoma, soft tissue sarcoma, leukemia, or Wilms tumor may also increase the risk of renal cell cancer. See the Second Cancers section in the PDQ summary about Late Effects of Treatment for Childhood Cancer for more information.

Treatment for Wilms tumor and other childhood kidney tumors may include genetic counseling.

Genetic counseling (a discussion with a trained professional about genetic diseases and whether genetic testing is needed) may be done if the child has one of the following syndromes or conditions:

• A genetic syndrome or condition that increases the risk of Wilms tumor.
• An inherited condition that increases the risk of renal cell cancer.
• Rhabdoid tumor of the kidney.
• Multilocular cystic nephroma.
• Anaplastic sarcoma of the kidney.

Signs of Wilms tumor and other childhood kidney tumors include a lump in the abdomen and blood in the urine.

Sometimes childhood kidney tumors do not cause signs and symptoms and the parent finds a mass in the abdomen by chance or the mass is found during a well-child health check-up. These and other signs and symptoms may be caused by kidney tumors or by other conditions. Check with your child's doctor if your child has any of the following:

• A lump, swelling, or pain in the abdomen.
• Blood in the urine.
• High blood pressure (headache, feeling very tired, chest pain, or trouble seeing or breathing).
• Hypercalcemia (loss of appetite, nausea and vomiting, weakness, or feeling very tired).
• Fever for no known reason.
• Loss of appetite.
• Weight loss for no known reason.

Wilms tumor that has spread to the lungs or liver may cause the following signs and symptoms:

• Cough.
• Blood in the sputum.
• Trouble breathing.
• Pain in the abdomen.

Tests that examine the kidney and the blood are used to diagnose Wilms tumor and other childhood kidney tumors.

The following tests and procedures may be used:

• Physical exam and health history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient's health habits and past illnesses and treatments will also be taken.
• Complete blood count (CBC): A procedure in which a sample of blood is drawn and checked for the following:
  • The number of red blood cells, white blood cells, and platelets.
  • The amount of hemoglobin (the protein that carries oxygen) in the red blood cells.
  • The portion of the blood sample made up of red blood cells.
• Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease. This test is done to check how well the liver and kidneys are working.
• Renal function test: A procedure in which blood or urine samples are checked to measure the amounts of certain substances released into the blood or urine by the kidneys. A higher or lower than normal amount of a substance can be a sign that the kidneys are not working as they should.
• Urinalysis: A test to check the color of urine and its contents, such as sugar, protein, blood, and bacteria.
• Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. An ultrasound of the abdomen is done to diagnose a kidney tumor.
  
  Abdominal ultrasound. An ultrasound transducer connected to a computer is pressed against the skin of the abdomen. The transducer bounces sound waves off internal organs and tissues to make echoes that form a sonogram (computer picture).
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the chest, abdomen, and pelvis, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye is injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  
  Computed tomography (CT) scan. The child lies on a table that slides through the CT scanner, which takes a series of detailed x-ray pictures of areas inside the body.
• MRI (magnetic resonance imaging) with gadolinium: A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the abdomen. A substance called gadolinium is injected into a vein. The gadolinium collects around the cancer cells so they show up brighter in the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  
  Magnetic resonance imaging (MRI) scan. The child lies on a table that slides into the MRI machine, which takes a series of detailed pictures of areas inside the body. The positioning of the child on the table depends on the part of the body being imaged.
• X-ray: An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body, such as the chest and abdomen.
• PET-CT scan: A procedure that combines the pictures from a positron emission tomography (PET) scan and a computed tomography (CT) scan. The PET and CT scans are done at the same time on the same machine. The pictures from both scans are combined to make a more detailed picture than either test would make by itself. A PET scan is a procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
• Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer. The decision of whether to do a biopsy is based on the following:
  • The size of the tumor.
  • The stage of the cancer. If the tumor appears to be resectable or stage I or stage II Wilms tumor, a biopsy is not done to avoid tumor cells being spread during the procedure.
  • Whether cancer is in one or both kidneys.
  • Whether imaging tests clearly show the cancer.
  • Whether the patient is in a clinical trial.
  A biopsy may be done before any treatment is given, after chemotherapy to shrink the tumor, or after surgery to remove the tumor.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis and treatment options for Wilms tumor depend on the following:

• How different the tumor cells are from normal kidney cells when looked at under a microscope.
• The stage of the cancer.
• The type of tumor.
• The age of the child.
• Whether the tumor can be completely removed by surgery.
• Whether there are certain changes in chromosomes or genes.
• Whether the cancer has just been diagnosed or has recurred (come back).

The prognosis for renal cell cancer depends on the following:

• The stage of the cancer.
• Whether the cancer has spread to the lymph nodes.

The prognosis for rhabdoid tumor of the kidney depends on the following:

• The age of the child at the time of diagnosis.
• The stage of the cancer.
• Whether the cancer has spread to the brain or spinal cord.

The prognosis for clear cell sarcoma of the kidney depends on the following:

• The age of the child at the time of diagnosis.
• The stage of the cancer.

Stages of Wilms Tumor

Wilms tumors are staged during surgery and with imaging tests.

The process used to find out if cancer has spread outside of the kidney to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. The results of the tests and procedures done to diagnose and stage Wilms tumor are used to help make decisions about treatment.

There is no staging for the other types of childhood kidney tumors. The treatment of these tumors depends on the tumor type.

The following tests may be done to see if cancer has spread to other places in the body:

• Lymph node biopsy: The removal of all or part of a lymph node in the abdomen. A pathologist views the lymph node tissue under a microscope to check for cancer cells. This procedure is also called lymphadenectomy or lymph node dissection.
• Liver function test: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by the liver. A higher than normal amount of a substance can be a sign that the liver is not working as it should.
• X-ray of the chest and bones: An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body, such as the chest.
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the abdomen, pelvis, chest, and brain, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye is injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• PET-CT scan: A procedure that combines the pictures from a positron emission tomography (PET) scan and a computed tomography (CT) scan. The PET and CT scans are done at the same time on the same machine. The pictures from both scans are combined to make a more detailed picture than either test would make by itself. A PET scan is a procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the abdomen, pelvis, and brain. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• Bone scan: A procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones with cancer and is detected by a scanner.
  
  Bone scan. A small amount of radioactive material is injected into the child's vein and travels through the blood. The radioactive material collects in the bones. As the child lies on a table that slides under the scanner, the radioactive material is detected and images are made on a computer screen.
• Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. An ultrasound of the major heart vessels is done to stage Wilms tumor.
• Cystoscopy: A procedure to look inside the bladder and urethra to check for abnormal areas. A cystoscope is inserted through the urethra into the bladder. A cystoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue samples, which are checked under a microscope for signs of cancer.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

• Tissue. The cancer spreads from where it began by growing into nearby areas.
• Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
• Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

• Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
• Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if Wilms tumor spreads to the lung, the cancer cells in the lung are actually Wilms tumor cells. The disease is metastatic Wilms tumor, not lung cancer.

In addition to the stages, Wilms tumors are described by their histology.

The histology (how the cells look under a microscope) of the tumor affects the prognosis and the treatment of Wilms tumor. The histology may be favorable or anaplastic (unfavorable). Tumors with a favorable histology have a better prognosis and respond better to chemotherapy than anaplastic tumors. Tumor cells that are anaplastic divide quickly and under a microscope do not look like the type of cells they came from. Anaplastic tumors are harder to treat with chemotherapy than other Wilms tumors at the same stage.

The following stages are used for both favorable histology and anaplastic Wilms tumors:

Stage I

In stage I, the tumor was completely removed by surgery and all of the following are true:

• Cancer was found only in the kidney and did not spread to blood vessels in the renal sinus (the part of the kidney where it joins the ureter) or to the lymph nodes.
• No cancer cells were found at the edges of the area where the tumor was removed.
• The outer layer of the kidney did not break open.
• The tumor did not break open.
• A biopsy was not done before the tumor was removed.

Stage II

In stage II, the tumor was completely removed by surgery and no cancer cells were found at the edges of the area where the cancer was removed. Cancer has not spread to lymph nodes. Before the tumor was removed, one of the following was true:

• Cancer had spread to the renal sinus (the part of the kidney where it joins the ureter).
• Cancer had spread to blood vessels outside the area of the kidney where urine is made, such as the renal sinus.

Stage III

In stage III, cancer remains in the abdomen after surgery and at least one of the following is true:

• Cancer has spread to lymph nodes in the abdomen or pelvis (the part of the body between the hips).
• Cancer has spread to or through the surface of the peritoneum (the tissue that lines the abdominal cavity and covers most organs in the abdomen).
• A biopsy of the tumor was done before it was removed.
• The tumor broke open before or during surgery to remove it.
• The tumor was removed in more than one piece.
• Cancer cells are found at the edges of the area where the tumor was removed.
• The entire tumor could not be removed because important organs or tissues in the body would be damaged.

Stage IV

In stage IV, cancer has spread through the blood to organs such as the lungs, liver, bone, or brain, or to lymph nodes outside the abdomen and pelvis.

Stage V (bilateral)

In stage V (bilateral) Wilms tumor, cancer cells are found in both kidneys when the cancer is first diagnosed. The cancer in each kidney is staged separately as stage I, II, III, or IV.

Sometimes Wilms tumor and other childhood kidney tumors come back after treatment.

Childhood Wilms tumor may recur (come back) in the lungs, abdomen, liver, or other places in the body.

Childhood clear cell sarcoma of the kidney may recur in the brain, lungs, or other places in the body.

Childhood congenital mesoblastic nephroma may recur in the kidneys or in other places in the body.

Treatment Option Overview

There are different types of treatment for patients with Wilms tumor and other childhood kidney tumors.

Different types of treatment are available for children with Wilms and other childhood kidney tumors. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.

Because cancer in children is rare, taking part in a clinical trial should be considered. Some clinical trials are open only to patients who have not started treatment.

Children with Wilms tumor or other childhood kidney tumors should have their treatment planned by a team of health care providers who are experts in treating cancer in children.

Your child's treatment will be overseen by a pediatric oncologist, a doctor who specializes in treating children with cancer. The pediatric oncologist works with other pediatric health care providers who are experts in treating children with Wilms tumor or other childhood kidney tumors and who specialize in certain areas of medicine. These may include the following specialists:

• Pediatrician.
• Pediatric surgeon or urologist.
• Radiation oncologist.
• Rehabilitation specialist.
• Pediatric nurse specialist.
• Social worker.

Six types of treatment are used:

Surgery

Two types of surgery are used to treat kidney tumors:

• Nephrectomy: Wilms tumor and other childhood kidney tumors are usually treated with nephrectomy (surgery to remove the whole kidney). Nearby lymph nodes may also be removed and checked for signs of cancer. Sometimes a kidney transplant (surgery to remove the kidney and replace it with a kidney from a donor) is done when the cancer is in both kidneys and the kidneys are not working well.
• Partial nephrectomy: If cancer is found in both kidneys or is likely to spread to both kidneys, surgery may include a partial nephrectomy (removal of the cancer in the kidney and a small amount of normal tissue around it). Partial nephrectomy is done to keep as much of the kidney working as possible. A partial nephrectomy is also called renal-sparing surgery.

After the doctor removes all the cancer that can be seen at the time of the surgery, some patients may be given chemotherapy or radiation therapy after surgery to kill any cancer cells that are left. Treatment given after the surgery, to lower the risk that the cancer will come back, is called adjuvant therapy. Sometimes, a second-look surgery is done to see if cancer remains after chemotherapy or radiation therapy.

Sometimes the tumor cannot be removed by surgery for one of the following reasons:

• The tumor is too close to important organs or blood vessels.
• The tumor is too large to remove.
• The cancer is in both kidneys, unless the tumors are very small.
• There is a blood clot in the vessels near the liver.
• The patient has trouble breathing because cancer has spread to the lungs.

In this case, a biopsy is done first. Then chemotherapy is given to reduce the size of the tumor before surgery, in order to save as much healthy tissue as possible and lessen problems after surgery. This is called neoadjuvant chemotherapy. Radiation therapy is given after surgery.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. External radiation therapy uses a machine outside the body to send radiation toward the area of the body with cancer.

External radiation therapy is used to treat Wilms tumor and other childhood kidney tumors.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). Combination chemotherapy is treatment using two or more anticancer drugs.

Systemic chemotherapy is used to treat Wilms tumor and other childhood kidney tumors.

Sometimes chemotherapy is given to reduce the size of the tumor before surgery, in order to save as much healthy tissue as possible and lessen problems after surgery. This is called neoadjuvant chemotherapy.

See Drugs Approved for Wilms Tumor and Other Childhood Kidney Cancers for more information.

Immunotherapy

Immunotherapy is a treatment that uses the patient's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defenses against cancer. This cancer treatment is a type of biologic therapy.

Interferon and interleukin-2 (IL-2) are types of immunotherapy used to treat childhood renal cell cancer. Interferon may slow tumor growth and may help kill the cancer cells. IL-2 boosts the growth and activity of many immune cells, especially lymphocytes (a type of white blood cell). Lymphocytes can attack and kill cancer cells.

High-dose chemotherapy with stem cell rescue

High doses of chemotherapy are given to kill cancer cells. Healthy cells, including blood -forming cells, are also destroyed by the cancer treatment. Stem cell rescue is a treatment to replace the blood-forming cells. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient and are frozen and stored. After the patient completes chemotherapy, the stored stem cells are thawed and given back to the patient through an infusion. These stem cells grow into (and restore) the body's blood cells.

High-dose chemotherapy with stem cell rescue may be used to treat rhabdoid tumor of the kidney or recurrent Wilms tumor.

Targeted therapy

Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells. Targeted therapies usually cause less harm to normal cells than chemotherapy or radiation therapy do. Targeted therapy used to treat childhood kidney tumors may include the following:

• Tyrosine kinase inhibitors: This targeted therapy blocks signals that cancer cells need to grow and divide.
  • Larotrectinib and entrectinib may be used to treat congenital mesoblastic nephroma with a certain gene change that cannot be removed by surgery, has spread to other parts of the body, or has continued to grow during treatment. This combination is also being studied to treat congenital mesoblastic nephroma that has come back after treatment.
  • Sunitinib or cabozantinib may be used to treat renal cell carcinoma.
  • Axitinib is being studied in combination with a monoclonal antibody (nivolumab) to treat renal cell carcinoma that cannot be removed by surgery or has spread to other parts of the body.
• Histone methyltransferase inhibitors: This targeted therapy may keep the cancer cells from growing and dividing. Tazemetostat is being studied to treat rhabdoid tumor of the kidney that does not respond or has come back after treatment.
• Monoclonal antibody therapy: Monoclonal antibodies are immune system proteins made in the laboratory to treat many diseases, including cancer. As a cancer treatment, these antibodies can attach to a specific target on cancer cells or other cells that may help cancer cells grow. The antibodies are able to then kill the cancer cells, block their growth, or keep them from spreading. Monoclonal antibodies are given by infusion. They may be used alone or to carry drugs, toxins, or radioactive material directly to cancer cells. Nivolumab or a combination of nivolumab and a tyrosine kinase inhibitor (axitinib) are being studied to treat renal cell carcinoma that cannot be removed by surgery or has spread to other parts of the body.monoclonal antibodies: how monoclonal antibodies treat cancerHow do monoclonal antibodies work to treat cancer? This video shows how monoclonal antibodies, such as trastuzumab, pembrolizumab, and rituximab, block molecules cancer cells need to grow, flag cancer cells for destruction by the body's immune system, or deliver harmful substances to cancer cells.

Other targeted therapies are being studied for the treatment of childhood kidney tumors that have recurred (come back).

New types of treatment are being tested in clinical trials.

Information about clinical trials is available from the NCI website.

Treatment for Wilms tumor and other childhood kidney tumors may cause side effects.

To learn more about side effects that begin during treatment for cancer, visit Side Effects.

Side effects from cancer treatment that begin after treatment and continue for months or years are called late effects. Late effects of cancer treatment may include the following:

• Physical problems, such as problems with the heart, the kidney, or during pregnancy.
• Infertility.
• Changes in mood, feelings, thinking, learning, or memory.
• Second cancers (new types of cancer), such as leukemias, cancer of the gastrointestinal tract, or breast cancer.

Some late effects may be treated or controlled. It is important to talk with your child's doctors about the effects cancer treatment can have on your child. (See the PDQ summary about Late Effects of Treatment for Childhood Cancer for more information).

Clinical trials are being done to find out if lower doses of chemotherapy and radiation can be used to lessen the late effects of treatment without changing how well the treatment works.

Monitoring for late effects involving the kidneys in patients with Wilms tumor and related conditions includes the following:

• Children with WAGR syndrome are monitored throughout their lives because they are at increased risk of developing hypertension and kidney disease.
• Children with Wilms tumor and abnormal genitourinary system are monitored because they are at increased risk of late kidney failure.
• Patients with Wilms tumor and aniridia without abnormal genitourinary system are at lower risk but are monitored for kidney disease or kidney failure.

Patients may want to think about taking part in a clinical trial.

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. Information about clinical trials supported by NCI can be found on NCI's clinical trials search webpage. Clinical trials supported by other organizations can be found on the ClinicalTrials.gov website.

Follow-up tests may be needed.

As your child goes through treatment, they will have follow-up tests or check-ups. Some tests that were done to diagnose or stage the cancer may be repeated to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your child's condition has changed or if the cancer has recurred (come back).

Treatment Options for Wilms Tumor

For information about the treatments listed below, see the Treatment Option Overview section.

Stage I Wilms Tumor

Treatment of stage I Wilms tumor with favorable histology may include:

• Nephrectomy with removal of lymph nodes, followed by combination chemotherapy.
• Nephrectomy with removal of lymph nodes.

Treatment of stage I anaplastic Wilms tumor may include:

• Nephrectomy with removal of lymph nodes, followed by combination chemotherapy and radiation therapy to the flank area (either side of the body between the ribs and hipbone).

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Stage II Wilms Tumor

Treatment of stage II Wilms tumor with favorable histology may include:

• Nephrectomy with removal of lymph nodes, followed by combination chemotherapy.

Treatment of stage II anaplastic Wilms tumor may include:

• Nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Stage III Wilms Tumor

Treatment of stage III Wilms tumor with favorable histology may include:

• Nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy.

Treatment of stage III anaplastic Wilms tumor may include:

• Nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy.
• Combination chemotherapy, followed by nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Stage IV Wilms Tumor

Treatment of stage IV Wilms tumor with favorable histology may include:

• Nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy. If cancer has spread to other parts of the body, patients will also receive radiation therapy to those areas.

Treatment of stage IV anaplastic Wilms tumor may include:

• Nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy. If cancer has spread to other parts of the body, patients will also receive radiation therapy to those areas.
• Combination chemotherapy given before nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen. If cancer has spread to other parts of the body, patients will also receive radiation therapy to those areas.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Stage V Wilms Tumor and patients at high risk of developing bilateral Wilms tumor

Treatment of stage V Wilms tumor (bilateral) may be different for each patient and may include:

• Combination chemotherapy to shrink the tumor, followed by repeat imaging at 4 to 8 weeks to decide on further therapy (partial nephrectomy, biopsy, continued chemotherapy, and/or radiation therapy).
• A biopsy of the kidneys is followed by combination chemotherapy to shrink the tumor. A second surgery is done to remove as much of the cancer as possible. This may be followed by more chemotherapy and/or radiation therapy if cancer remains after surgery.

If a kidney transplant is needed because of kidney problems, it is usually delayed until 1 to 2 years after treatment is completed and there are no signs of cancer.

(See the Treatment of Recurrent Childhood Kidney Tumors section of this summary for information about recurrent disease.)

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Treatment Options for Other Childhood Kidney Tumors

For information about the treatments listed below, see the Treatment Option Overview section.

Renal Cell Cancer (RCC)

Treatment of renal cell cancer may include:

• Surgery, which may be:
  • nephrectomy with removal of lymph nodes; or
  • partial nephrectomy with removal of lymph nodes.
• Immunotherapy (interferon or interleukin-2) for cancer that has spread to other parts of the body.
• Targeted therapy (tyrosine kinase inhibitors, such as sunitinib or cabozantinib) for cancer that has spread to other parts of the body.
• A clinical trial of targeted therapy with monoclonal antibody therapy (nivolumab) or a combination of nivolumab with a tyrosine kinase inhibitor (axitinib) for cancer that has a certain gene change and cannot be removed by surgery or has spread to other parts of the body.

See the PDQ summary about Renal Cell Cancer Treatment for more information.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Rhabdoid Tumor of the Kidney

There is no standard treatment for rhabdoid tumor of the kidney. Treatment may include:

• A combination of surgery, chemotherapy, and/or radiation therapy.
• High-dose chemotherapy with or without stem cell rescue.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Clear Cell Sarcoma of the Kidney

Treatment of clear cell sarcoma of the kidney may include:

• Nephrectomy with removal of lymph nodes followed by combination chemotherapy (including doxorubicin) and radiation therapy to the abdomen.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Congenital Mesoblastic Nephroma

Treatment of stages I, II, and certain patients with stage III congenital mesoblastic nephroma may include:

• Surgery.

Treatment for certain patients with stage III congenital mesoblastic nephroma may include:

• Surgery followed by chemotherapy.

A clinical trial of targeted therapy with a tyrosine kinase inhibitor (larotrectinib) for cancer that has a certain gene change and has not been treated.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Ewing Sarcoma of the Kidney

There is no standard treatment for Ewing sarcoma of the kidney. Treatment may include:

• A combination of surgery, chemotherapy, and radiation therapy.

It may also be treated in the same way that Ewing sarcoma is treated. See the PDQ summary about Ewing Sarcoma Treatment for more information.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

Primary Renal Myoepithelial Carcinoma

There is no standard treatment for primary renal myoepithelial carcinoma. Treatment may include:

• A combination of surgery, chemotherapy, and radiation therapy.

Cystic Partially Differentiated Nephroblastoma

Treatment of cystic partially differentiated nephroblastoma may include:

• Surgery that may be followed by chemotherapy.

Multilocular Cystic Nephroma

Treatment of multilocular cystic nephroma usually includes:

• Surgery.

Primary Renal Synovial Sarcoma

Treatment of primary renal synovial sarcoma usually includes:

• Chemotherapy.

Anaplastic Sarcoma of the Kidney

There is no standard treatment for anaplastic sarcoma of the kidney. Treatment is usually the same treatment given for anaplastic Wilms tumor.

Nephroblastomatosis (Diffuse Hyperplastic Perilobar Nephroblastomatosis)

The treatment of nephroblastomatosis depends on the following:

• Whether the child has abnormal groups of cells in one or both kidneys.
• Whether the child has Wilms tumor in one kidney and groups of abnormal cells in the other kidney.

Treatment of nephroblastomatosis may include:

• Chemotherapy followed by nephrectomy. Sometimes a partial nephrectomy may be done to keep as much kidney function as possible.

Treatment of Recurrent Childhood Kidney Tumors

For information about the treatments listed below, see the Treatment Option Overview section.

Treatment of recurrent Wilms tumor may include:

• Combination chemotherapy, surgery, and radiation therapy.
• Combination chemotherapy and radiation therapy, followed by stem cell rescue, using the child's own blood stem cells.
• A clinical trial that checks a sample of the patient's tumor for certain gene changes. The type of targeted therapy that will be given to the patient depends on the type of gene change.
• A clinical trial of combination chemotherapy for patients with relapsed favorable histology Wilms tumor.

Treatment of recurrent rhabdoid tumor of the kidney may include:

• A clinical trial that checks a sample of the patient's tumor for certain gene changes. The type of targeted therapy that will be given to the patient depends on the type of gene change.

Treatment of recurrent clear cell sarcoma of the kidney may include:

• Combination chemotherapy, surgery to remove the tumor (if possible), with or without radiation therapy.
• A clinical trial that checks a sample of the patient's tumor for certain gene changes. The type of targeted therapy that will be given to the patient depends on the type of gene change.

Treatment of recurrent congenital mesoblastic nephroma may include:

• Combination of chemotherapy, surgery, and radiation therapy.
• Targeted therapy such as larotrectinib or entrectinib.
• A clinical trial that checks a sample of the patient's tumor for certain gene changes. The type of targeted therapy that will be given to the patient depends on the type of gene change.
• A clinical trial of targeted therapy (LOXO-101 or entrectinib).

Treatment of other recurrent childhood kidney tumors is usually within a clinical trial.

Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.

To Learn More About Wilms Tumor and Other Childhood Kidney Tumors

For more information from the National Cancer Institute about Wilms tumor and other childhood kidney tumors, see the following:

• Kidney Cancer Home Page
• Computed Tomography (CT) Scans and Cancer
• Drugs Approved for Wilms Tumor and Other Childhood Kidney Cancers
• Immunotherapy to Treat Cancer
• Targeted Cancer Therapies
• Genetic Testing for Inherited Cancer Susceptibility Syndromes

For more childhood cancer information and other general cancer resources, visit:

• About Cancer
• Childhood Cancers
• CureSearch for Children's Cancer
• Late Effects of Treatment for Childhood Cancer
• Adolescents and Young Adults with Cancer
• Children with Cancer: A Guide for Parents
• Cancer in Children and Adolescents
• Staging
• Coping with Cancer
• Questions to Ask Your Doctor about Cancer
• For Survivors and Caregivers

About This PDQ Summary

About PDQ

Physician Data Query (PDQ) is the National Cancer Institute's (NCI's) comprehensive cancer information database. The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come in two versions. The health professional versions have detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions have cancer information that is accurate and up to date and most versions are also available in Spanish.

PDQ is a service of the NCI. The NCI is part of the National Institutes of Health (NIH). NIH is the federal government's center of biomedical research. The PDQ summaries are based on an independent review of the medical literature. They are not policy statements of the NCI or the NIH.

Purpose of This Summary

This PDQ cancer information summary has current information about the treatment of Wilms tumor and other childhood kidney tumors. It is meant to inform and help patients, families, and caregivers. It does not give formal guidelines or recommendations for making decisions about health care.

Reviewers and Updates

Editorial Boards write the PDQ cancer information summaries and keep them up to date. These Boards are made up of experts in cancer treatment and other specialties related to cancer. The summaries are reviewed regularly and changes are made when there is new information. The date on each summary ("Updated") is the date of the most recent change.

The information in this patient summary was taken from the health professional version, which is reviewed regularly and updated as needed, by the PDQ Pediatric Treatment Editorial Board.

Clinical Trial Information

A clinical trial is a study to answer a scientific question, such as whether one treatment is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. During treatment clinical trials, information is collected about the effects of a new treatment and how well it works. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Clinical trials can be found online at NCI's website. For more information, call the Cancer Information Service (CIS), NCI's contact center, at 1-800-4-CANCER (1-800-422-6237).

Permission to Use This Summary

PDQ is a registered trademark. The content of PDQ documents can be used freely as text. It cannot be identified as an NCI PDQ cancer information summary unless the whole summary is shown and it is updated regularly. However, a user would be allowed to write a sentence such as "NCI's PDQ cancer information summary about breast cancer prevention states the risks in the following way: [include excerpt from the summary]."

The best way to cite this PDQ summary is:

PDQ® Pediatric Treatment Editorial Board. PDQ Wilms Tumor and Other Childhood Kidney Tumors Treatment. Bethesda, MD: National Cancer Institute. Updated <MM/DD/YYYY>. Available at: https://www.cancer.gov/types/kidney/patient/wilms-treatment-pdq. Accessed <MM/DD/YYYY>. [PMID: 26389390]

Images in this summary are used with permission of the author(s), artist, and/or publisher for use in the PDQ summaries only. If you want to use an image from a PDQ summary and you are not using the whole summary, you must get permission from the owner. It cannot be given by the National Cancer Institute. Information about using the images in this summary, along with many other images related to cancer can be found in Visuals Online. Visuals Online is a collection of more than 3,000 scientific images.

Disclaimer

The information in these summaries should not be used to make decisions about insurance reimbursement. More information on insurance coverage is available on Cancer.gov on the Managing Cancer Care page.

Contact Us

More information about contacting us or receiving help with the Cancer.gov website can be found on our Contact Us for Help page. Questions can also be submitted to Cancer.gov through the website's E-mail Us.

Last Revised: 2021-08-18

If you want to know more about cancer and how it is treated, or if you wish to know about clinical trials for your type of cancer, you can call the NCI's Cancer Information Service at 1-800-422-6237, toll free. A trained information specialist can talk with you and answer your questions.