Wilms Tumor Diagnosis

The following tests and procedures may be used to diagnose Wilms tumor:
  • 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 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 in the organ or tissue that makes 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 tumor.
  • 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, computerized tomography, or computerized 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.
Factors Affecting Prognosis and Treatment Options The prognosis (chance of recovery) and treatment options for Wilms Tumors depend on the following:
  • How different the tumor cells are from normal kidney cells.
  • The stage of the cancer.
  • The type and size of the tumor.
  • The age of the child.
  • Whether the tumor 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 pediatric experts with experience in treating patients with Wilms tumor.

Stages of Wilms Tumor and Other Childhood Kidney Tumors

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 tumor, 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, computerized tomography, or computerized 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 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.
Cancer spreads in the body through tissue, blood or lymph system. When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. 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 those with anaplastic histology. Tumor cells that are anaplastic divide rapidly and 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 of the kidney.
  • The outer layer of the kidney did not break open.
  • The tumor did not break open.
  • A biopsy of the tumor was not done.
  • No cancer cells were found at the edges of the area where 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. Before the tumor was removed, one of the following was true:
  • Cancer had spread out of the kidney to nearby soft tissue.
  • Cancer had 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).
  • Chemotherapy was given before surgery and a biopsy of the tumor was done during surgery to remove it.
  • The tumor broke open before or during surgery to remove it.
  • The tumor 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 Tumor and Other Childhood Kidney Tumors

Recurrent cancer is cancer that has recurred (come back) after it has been treated. Contact us to request an appointment with one of the oncologists at Diablo Valley Oncology discuss the treatment options available to treat Wilms Tumors.