Wilms' Tumour and Other Childhood Kidney Tumours

Key Points for This Section

  • Wilms' tumour and other childhood kidney tumours are diseases in which malignant (cancer) cells form in the tissues of the kidney.
  • Having certain genetic syndromes or birth defects can increase the risk of developing Wilms' tumour.
  • Possible signs of Wilms' tumour and other childhood kidney tumours include a lump in the abdomen and blood in the urine.
  • Tests that examine the kidney and the blood are used to detect (find) Wilms' tumour and other childhood kidney tumours.
  • Wilms' tumour and other childhood kidney tumours are usually diagnosed and removed in surgery.
  • Certain factors affect prognosis (chance of recovery) and treatment options.

Wilms' tumour and other childhood kidney tumours are diseases in which malignant (cancer) cells form in the tissues of the kidney.

Wilms' tumour

Wilms' tumour and other kidney tumours are diseases in which malignant (cancer) cells are found in the kidney. In Wilms' tumour, one or more tumours may be found in one or both kidneys. There are two kidneys, one on each side of the backbone, above the waist. Tiny tubules in the kidneys filter and clean the blood, taking out waste products and making urine. The urine passes from each kidney through a long tube called a ureter into the bladder. The bladder holds the urine until it is passed from the body.

Wilms' tumour may spread to the lungs, liver, or nearby lymph nodes.

Other kidney tumours

Clear cell sarcoma of the kidney, rhabdoid tumour of the kidney, and neuroepithelial tumour of the kidney are also childhood kidney tumours, but they are not related to Wilms' tumour.

  • Clear cell sarcoma of the kidney is a type of kidney tumour that may spread to the lung, bone, brain, and soft tissue.
  • Rhabdoid tumour of the kidney is a type of cancer that occurs mostly in children under age 2. It grows and spreads quickly, often to the lungs and brain.
  • Neuroepithelial tumours of the kidney are rare and usually occur in young adults. They grow and spread quickly.

Having certain genetic syndromes or birth defects can increase the risk of developing Wilms' tumour.

Wilms' tumour may be part of a genetic syndrome that affects growth or development. A genetic syndrome is a set of symptoms or conditions that occur together and is usually caused by abnormal genes. Certain birth defects can also increase a child's risk for developing Wilms' tumour. The following genetic syndromes and birth defects have been linked to Wilms' tumour:

  • WAGR (Wilms' tumour, aniridia, ambiguous genitalia, and mental retardation) syndrome.
  • Beckwith-Wiedemann syndrome.
  • Hemihypertrophy.
  • Denys-Drash syndrome.
  • Cryptorchidism.
  • Hypospadias.

Children with these genetic syndromes and birth defects should be screened for Wilms' tumour every three months until age 8. An ultrasound test may be used for screening.

Possible signs of Wilms' tumour and other childhood kidney tumours include a lump in the abdomen and blood in the urine.

These and other symptoms may be caused by kidney tumours. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur in the child:

  • A lump, swelling, or pain in the abdomen.
  • Blood in the urine.
  • Fever for no known reason.

Tests that examine the kidney and the blood are used to detect (find) Wilms' tumour and other childhood kidney tumours.

The following tests and procedures may be used:

  • Physical exam and 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 haemoglobin (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 in the organ or tissue that produces it.
  • 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.
  • 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 tumour.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerised tomography, or computerised axial tomography.
  • Abdominal x-ray: An x-ray of the organs inside the abdomen. 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.
  • Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer.

Wilms' tumour and other childhood kidney tumours are usually diagnosed and removed in surgery.

Once a kidney tumour is found, surgery is done to find out whether or not the tumour is cancer. If the tumour is only in the kidney, the surgeon will remove the whole kidney (nephrectomy). If there are tumours in both kidneys or if the tumour has spread outside the kidney, a piece of the tumour will be removed. In any case, a sample of tissue from the tumour is sent to a pathologist, who looks at it under a microscope to check for signs of cancer.

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

The prognosis (chance of recovery) and treatment options depend on the following:

  • How different the tumour cells are from normal kidney cells.
  • The stage of the cancer.
  • The type and size of the tumour.
  • The age of the child.
  • Whether the tumour can be completely removed in surgery.
  • Whether the cancer has just been diagnosed or has recurred (come back).
  • Whether there are any abnormal chromosomes or genes.
  • Whether the patient is treated by paediatric experts with experience in treating patients with Wilms' tumour.

Stages of Wilms' Tumour and Other Childhood Kidney Tumours

Key Points for This Section

  • Wilms' tumours and other childhood kidney tumours are staged during surgery and with imaging tests.
  • In addition to the stages, Wilms' tumours are described by their histology.
  • The following stages are used for both favorable and unfavorable histology Wilms' tumours:
    • o Stage I
    o Stage II
    o Stage III
    o Stage IV
    o Stage V

    Wilms' tumours and other childhood kidney tumours 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. It is important to know the stage in order to plan treatment.

    For Wilms' tumours, the stage is determined during the initial surgery and with the results from imaging tests. The following imaging tests may be done to see if cancer has spread to other places in the body:

    • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the chest or brain, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerised tomography, or computerised axial tomography.
    • 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.
    • 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 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 and is detected by a scanner.
    • 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' tumour.

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

    The histology (how the cells look under a microscope) of the tumour affects the prognosis and may be favorable or unfavorable. Tumours with a favorable histology respond better to treatment than those with unfavorable histology.

    • Favorable histology: The cancer cells look like normal kidney cells.
    • Unfavorable histology: The cancer cells are anaplastic, which means they divide rapidly and look very different from normal kidney cells. Anaplastic tumours may be focal (in one area) or diffuse (spread widely throughout an area). Focal tumours have a better prognosis than diffuse tumours.

    The following stages are used for both favorable and unfavorable histology Wilms' tumours:

    Stage I

    In stage I, the tumour 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 of the kidney.
    • The outer layer of the kidney did not break open.
    • The tumour did not break open.
    • A biopsy of the tumour was not done.
    • No cancer cells are found at the edges of the area where the tumour was removed.

    Stage II

    In stage II, the tumour was completely removed by surgery and no cancer cells are found at the edges of the area where the cancer was removed. Also, one of the following is true:

    • Cancer spread out of the kidney to nearby soft tissue.
    • Cancer spread to blood vessels of the kidney.

    Stage III

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

    • Cancer spread to lymph nodes in the abdomen or pelvis (the part of the body between the hips).
    • Cancer spread to or through the surface of the peritoneum (the layer of tissue that lines the abdominal cavity and covers most organs in the abdomen).
    • A biopsy of the tumour was done during surgery to remove it.
    • The tumour was removed in more than one piece.

    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 of the abdomen and pelvis.

    Stage V

    In stage V, cancer cells are found in both kidneys when the disease is first diagnosed. Each kidney will be staged separately as I, II, III, or IV.

    Recurrent Wilms' Tumour and Other Childhood Kidney Tumours

    Recurrent cancer is cancer that has recurred (come back) after it has been treated.

    Treatment Option Overview

    Key Points for This Section

    • There are different types of treatment for patients with Wilms' tumour and other childhood kidney tumours.
    • Children with Wilms' tumour or other childhood kidney tumours should have their treatment planned by a team of doctors with expertise in treating cancer in children.
    • Three types of standard treatment are used:
      • o Surgery
      o Radiation therapy
      o Chemotherapy
    • New types of treatment are being tested in clinical trials. These include the following:
      • o High-dose chemotherapy with stem cell transplant
    • Late effects may be caused by cancer treatment.

    There are different types of treatment for patients with Wilms' tumour and other childhood kidney tumours.

    Different types of treatment are available for children with Wilms' and other childhood kidney tumours. 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. Clinical trials are taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI Web site. Choosing the most appropriate cancer treatment is a decision that ideally involves the patient, family, and health care team.

    Children with Wilms' tumour or other childhood kidney tumours should have their treatment planned by a team of doctors with expertise in treating cancer in children.

    Your child's treatment will be overseen by a paediatric oncologist. a doctor who specializes in treating children with cancer. The paediatric oncologist may refer you to other doctors who have experience and expertise in treating children with Wilms' tumour or other childhood kidney tumours and who specialize in certain areas of medicine. These may include the following specialists:

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

    Three types of standard treatment are used:

    Surgery

    Wilms' tumour and other childhood kidney tumours are usually treated with nephrectomy (surgery to remove the whole kidney). Nearby lymph nodes may also be removed.

    If cancer is found in 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 the kidney working.

    Even if 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 increase the chances of a cure, is called adjuvant therapy. Sometimes, a second-look surgery is done to see if cancer remains after chemotherapy or radiation therapy.

    Radiation therapy

    Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.

    Chemotherapy

    Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells 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). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.

    Combination chemotherapy is treatment using two or more anticancer drugs.

    New types of treatment are being tested in clinical trials. These include the following:

    High-dose chemotherapy with stem cell transplant

    High-dose chemotherapy with stem cell transplant is a method of giving high doses of chemotherapy and replacing blood-forming cells destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient or a donor and are frozen and stored. After the chemotherapy is completed, the stored stem cells are thawed and given back to the patient through an infusion. These re-infused stem cells grow into (and restore) the body's blood cells.

    Late effects may be caused by cancer treatment.

    Some cancer treatments cause side effects that continue or appear months or years after cancer treatment has ended. These are called late effects. (See the summary on Late Effects of Treatment for Childhood Cancer for more information.) It is important that parents of children who are treated for cancer know about the possible late effects caused by certain treatments. After several years, some patients develop another form of cancer as a result of their treatment with chemotherapy and radiation. Clinical trials are ongoing to find out if lower doses of chemotherapy and radiation can be used.

    Treatment Options for Wilms' Tumour and Other Childhood Kidney Tumours

    Stage I Wilms' Tumour

    Treatment of stage I Wilms' tumour with either favorable or unfavorable histology may include the following:

    • Nephrectomy with lymph node removal, followed by combination chemotherapy.
    • A clinical trial of nephrectomy alone.

    Stage II Wilms' Tumour

    Treatment of stage II Wilms' tumour with favorable histology is usually nephrectomy with removal of lymph nodes, followed by combination chemotherapy.

    Treatment of stage II Wilms' tumour with unfavorable histology is usually nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy.

    Stage III Wilms' Tumour

    Treatment of stage III Wilms' tumour with either favorable or unfavorable histology is usually nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy.

    Stage IV Wilms' Tumour

    Treatment of stage IV Wilms' tumour with either favorable or unfavorable histology is usually nephrectomy with removal of lymph nodes, followed by radiation therapy to the abdomen and combination chemotherapy. Some patients may also receive radiation therapy to the lungs.

    Stage V Wilms' Tumour

    Treatment of stage V Wilms' tumour may be different for each patient. Treatment is usually chemotherapy to shrink the tumour, followed by surgery 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.

    Inoperable Tumours

    Sometimes the tumour is inoperable (cannot be removed by surgery) because it is too close to important organs or blood vessels or because it is too large to remove. In this case, chemotherapy may be given to reduce the size of the tumour so it may be removed in surgery. If the tumour does not shrink enough after chemotherapy, radiation therapy may be given to shrink it further so that surgery may be done. This may be followed by more chemotherapy and/or more radiation therapy.

    Clear Cell Sarcoma of the Kidney

    There is no standard treatment for clear cell sarcoma of the kidney. Treatment is usually within a clinical trial and may include nephrectomy, followed by radiation therapy to the abdomen and combination chemotherapy. Some patients may also receive radiation therapy to the lungs.

    Rhabdoid Tumour of the Kidney

    There is no standard treatment for rhabdoid tumour of the kidney. Treatment may be within a clinical trial and may include combination chemotherapy.

    Neuroepithelial Tumour of the Kidney

    There is no standard treatment for neuroepithelial tumour of the kidney. Treatment is usually within a clinical trial. It may be treated in the same way that Ewing's family of tumours or primitive neuroectodermal tumours are treated. See the summary on Ewing's Family of Tumours Treatment for more information.

    Information about ongoing clinical trials is available from the NCI Web site.
    Recurrent Wilms' Tumour and Other Childhood Kidney Tumours

    Treatment of recurrent Wilms' tumour may be within a clinical trial of combination chemotherapy, surgery, and radiation therapy, with or without stem cell transplant, using the child's own blood stem cells.

    Treatment of recurrent clear cell sarcoma, rhabdoid tumour, and neuroepithelial tumour of the kidney is usually within a clinical trial.


© Medic8 ® All Rights Reserved.