14 Jul What is Wilms’ Tumor?
Dr. Navneet Sharda provides this information as an educational source. It is not intended as a substitute for a consultation with a qualified healthcare provider.
Wilms’ tumor, also called nephroblastoma, is the most common type of kidney cancer that affects children. It is listed as a rare diseased by the Office of Rare Diseases of the National Institute of Health because it affects less than 200,000 people in the US population. Approximately 5.6 percent of the “children cancers” are Wilms’ tumors.
It predominantly occurs in the first five years of the child’s life, especially around age three or four (which is the peak age for this type of cancer), and rarely occurs in children older than 8 years. It usually affects only one kidney, but in few cases (5 percent) tumors occur in both kidneys.
Unfortunately, Wilm’s tumor is diagnosed only when the tumor(s) is/are already big, but before the cancer metastasize (spreads throughout the body). The average weight of a Wilms’ tumor when discovered is around one pound, but in some cases can be larger than the kidney where it developed.
Wilms’ Tumor Signs and Symptoms
Unfortunately, Wilms Tumor might go undetected until the tumor reaches a large size and becomes noticeable or can be felt. The symptoms can vary between patients. Wilms’ tumor may also go undetected early on, because the tumors can grow large without causing pain. However, even when they’re large, most of these tumors are found before they have a chance to spread (metastasize) to other parts of the body. Some of the common Wilms’ tumor signs and symptoms are:
- Abdominal pain
- Abdominal swelling
- Abdominal mass
- Blood in urine (this symptom occur in less than ¼ of the children)
- Loss of appetite
- High blood pressure
- General discomfort.
- Erythrocytosis (a medical condition where there are too many red cells in the blood)
Medical Tests and Diagnosis
Wilms‘ tumor symptoms can be signs of other medical conditions and only a doctor can establish a correct diagnosis. The diagnosis procedure involves a certain number of steps:
Anamnesis: One of the first steps in establishing a Wilms’ tumor diagnosis is a detailed and complex medical review of a patient’s past health problems and general health state, family medical history, risk factors, and symptoms.
Physical examination: During the physical examination, the doctor looks for abdominal masses that can be felt by touch and also measure the blood pressure.
Blood tests: In patients that might suffer from Wilms‘ tumor, a complete blood count (CBC) is performed. This set of tests measures: (1) the number of red and white blood cells, (2) the total amount of hemoglobin in the blood, (3) the size of red blood cells, and (4) the fraction of the blood composed of red blood cells. Another blood test performed is called serum creatinine, and it measures the level of creatinine in the blood.
Urine tests: There are two urine tests performed in patients with Wilms’ tumor: (1) blood urea nitrogen (BUN) – this test measures the amount of nitrogen in the blood that comes from urea (a substance produced by the liver, which is removed from the blood by the kidneys), and (2) urinalysis or routine urine test – is a physical and chemical examination of the urine.
Creatinine clearance: This is a test that compares the level of creatinine from the urine with the one from the blood.
Abdominal Ultrasound is an easy, noninvasive, fast, and painless imaging technique that uses high-frequency sound waves to create an interior image of the body on a special computer screen.
Abdominal X-ray is an imaging test that uses high energy electromagnetic radiation to penetrate the body and create the interior image on film. An abdominal x-ray can reveal the presence of kidney tumor(s) and provides useful information regarding the size, location and the extent of the tumor.
Chest X-ray is a test similar with the abdominal x-ray performed in order to reveal if the cancer has spread to other organs within the chest cavity.
Intravenous Pyelogram is an x-ray type technique designed to study the kidneys, bladder, and ureters.
Computed Tomography (CT) is an imaging test which is similar with an x-ray test, and creates a detailed cross-sectional image of the body.
Magnetic Resonance Imaging is an imaging technique which uses radio waves and strong magnets to reveal a complete image of the liver. The energy from the radio waves is absorbed by the tissues and then revealed into a recognizable pattern on a special monitor.
Bone scan is an imaging technique used to detect whether or not the cancer has affected the bones.
Biopsy is a medical procedures which confirms if the tumor or abnormal growth is a malignant tissue or not. A biopsy is a medical procedure where a sample of tissue is removed from the kidney tumor.
Wilms‘ tumor is best treated when diagnosed in the early stages, before the cancer has spread in the body.The treatment options for Wilms’ tumor include: surgery, chemotherapy, and radiation therapy.
Surgery Surgery is the main treatment approach used in patients with Wilms’ tumor in the USA. In Europe, the patient undergoes surgery after they receive chemotherapy.
Surgical removal of the kidney tissue is called nepherectomy. There are four types of nepherectomy performed in patients with Wilms’ tumor:
Simple nepherectomy: During this surgery, the doctor removes the entire kidney where the tumor is present.
Partial nepherectomy: During this surgery, the doctor removes the tumor together with the surrounding kidney tissue.
Radical nephetectomy: During this surgery, the doctor removes the tumor together with the entire kidney, the ureters (thin tube that carries the urine from the kidney to the urine bladder), the adrenal gland, the fat tissue that capsules the kidney, and sometimes with the adjacent lymph nodes.
Nephron-sparing surgery: During this surgery, the doctor tries to remove only the tumor with as little damage to the kidney tissue as possible.
Chemotherapy Chemotherapy is a systemic treatment (affects cells throughout the entire body) that uses drugs either to stop the abnormal growth and dividing process of the cancer cells, or to kill the cancer cells. This treatment can be administrated as pills, through injections, or through a catheter placed in a blood vessel.
Radiation Therapy This is a treatment approach which uses high-energy rays or particles to destroy cancerous cells.