Most people are born with two kidneys. They are placed on either side of the spine just above your waist. The kidneys remove waste from your body, produce hormones to help control blood pressure, and tell your bones when to make more red blood cells. If cancer cells begin to grow in the kidneys, they can cause kidney cancer.
The three most common types of kidney cancers are:
- Renal cell carcinoma. Renal cell carcinoma (another word for cancer) is the most common type of kidney cancer. About 9 out of 10 kidney cancers are renal cell carcinomas.
- Transitional cell carcinoma (urothelial carcinoma). This type of cancer starts in the renal pelvis. This is the area where the ureters meet the kidney. The ureters are the narrow tubes that take urine to the bladder.
- Wilms tumor (nephroblastoma). This is the most common tumor in children under five years old. Wilms tumors usually only happen in one kidney and can grow very large before they are noticed. Most are found before they spread to other parts of the body.
Wilms tumor and renal cell cancers form in the tiny tubules of the kidney. The tubules filter waste and make urine.
Some possible signs and symptoms of kidney cancer include:
- Blood in the urine
- Low back pain
- Mass (lump) on the abdomen (belly) or lower back
- Extreme tiredness (fatigue)
- Loss of appetite
- Unexplained weight loss
- Fever that doesn’t go away
If you have any of the symptoms listed above, contact your healthcare provider. These symptoms may also be caused by other medical conditions, so it is important to see your doctor.
It is not clear what causes kidney cancer. Certain risk factors increase the chances that a person will develop kidney cancer. Risk factors are anything that can increase your chances of getting a disease. Risk factors include:
- Having a family history of kidney cancer
- Having certain inherited medical conditions
- Carrying too much weight (obesity)
- Taking a lot of over-the-counter or prescription pain medicines over a long time
- High blood pressure
Having a risk factor, or several risk factors, does not mean that you will get kidney cancer.
To diagnose kidney cancer of kidney cancer, your doctor will ask about your medical history and do a physical exam. You will likely need tests to rule out other causes of your symptoms. The following tests may be used to confirm or rule out kidney cancer:
- Blood tests. These are done to look for certain substances in your blood.
- Urinalysis. This test is used to check the color of urine and can tell your doctor if red and white blood cells, sugar, and protein are present.
- Imaging tests. Ultrasound, CT (computed tomography), and MRI (magnetic resonance imaging) scans, or an IVP (intravenous pyelogram) may be done to take detailed images of your kidney and the area around it.
- Biopsy. Small pieces of tissue are taken from the kidney and surrounding tissue. They are examined under a microscope for signs of cancer.
If left untreated, kidney cancer can spread to other parts of the body. You will work with your cancer specialists to choose a treatment plan that’s best for you. When choosing a treatment plan, one of the most important factors is how far the cancer has grown or spread (referred to as the stage of the cancer). Depending on the stage, you may need a combination of different treatments.
- Surgery may be recommended to remove a tumor or cancer cells from the surrounding tissue.
- Chemotherapy [kee-moh-THER-uh-pee] is targeted drug therapy. Doctors use specific medicines to target your type and stage of cancer.
- Radiation therapy uses targeted x-rays to kill cancer cells.
- Immunotherapy (also called biologic therapy) is a way to boost your own cells to help fight cancer.
- Ablation and other therapies may be recommended if you are too sick to have surgery or chemotherapy.
There is no known way to prevent kidney cancer. However, maintaining a healthy weight, controlling high blood pressure, not smoking, and avoiding exposure to harsh chemicals may reduce your risk of developing kidney cancer.