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Like other major organs in the body, your kidneys can sometimes develop cancer. In adults, renal cell carcinoma (renal adenocarcinoma), which begins in the cells that line the small tubes within your kidneys, is the most common type of kidney cancer.

Kidney cancer seldom causes problems in its early stages. But as a tumor grows, you may notice blood in your urine or lose weight without trying or feel back pain that doesn't go away. Kidney cancer cells may also spread (metastasize) outside your kidneys to nearby organs as well as to more distant sites in the body.

A brief history of kidney cancer 

First reported in 1826, scientists have yet to discover the cause of renal cancer. Kidney cancer occurs most often after the age of 40; however, children as young as six months have also been diagnosed. While renal cell is the most common type of kidney cancer in adults, a less common type is called transitional cell cancer. Wilm’s tumor is the most common type diagnosed in children. A rare kidney cancer, called renal sarcomas, begins in the connective tissue of the kidney. This type makes up less than one-percent of all renal cancers. While the renal cancer can spread rapidly to other parts of the body, chances for a full recovery are typically good if detected and treated early.

Does CKD or ESRD lead to kidney cancer?

A 2005 study by the United States Renal Data System (USRDS) found a link between kidney cancer and end stage renal disease (ESRD). Study results showed that an increased number of kidney-cancer patients later developed ESRD during their treatment; similarly patients with either chronic kidney disease (CKD) or ESRD showed an increased number of patients who developed renal cancer after long-term hemodialysis. 

Those on long-term kidney dialysis have an increased risk of developing kidney cysts and this increases the risk of kidney cancer. Experts believe this risk is due to the kidney disease rather than the dialysis. Dialysis is not directly related to cancer risk.

Risk factors for kidney cancer

Just what causes kidney cells to become cancerous isn't clear. The risk of kidney cancer increases with age, occurring most often between the ages of 50 and 70. Kidney cancer affects almost twice as many men as women. It also tends to be somewhat more common in African American men than white men.

Researchers have also identified other factors that appear to increase the risk of developing both renal and transitional cell kidney cancers.

Other possible risk factors include:

• Smoking
• Obesity
• Some occupational exposures, such as coke-oven workers in steel plants or asbestos in the workplace
• Some types of radiation treatment, such as that used for disorders of the uterus
• Heavy, long-term use of phenacetin, a pain relieving drug, no longer sold in the U.S.
• An inherited disorder called Von Hippel Lindau Disease

Knowing these risk factors is critical to prevention and successful treatment.

Symptoms of renal cancer

Because kidney cancer rarely causes noticeable symptoms in the early stages, it is usually detected by chance; either during routine exams or testing for other unrelated complaints. As the disease advances, some symptoms may occur, such as blood in the urine.

Other possible symptoms may include:

• Back pain felt just below the ribs that doesn't go away
• A mass in the area of the kidneys that's discovered during an examination
• Weight loss
• Fatigue
• Intermittent fever
• Pain in other parts of the body if the cancer has spread
• High blood pressure
• Anemia (a decrease in the number of red cells in the blood)

Wilms' tumor usually has no symptoms, and doctors are likely to discover this condition when examining a child's abdomen. Keep in mind that these symptoms can also be caused by less serious problems such as a cyst or an infection. If you have any of these symptoms, check with your doctor. The doctor will perform the necessary tests to find out the source of your problem.

Methods of detection

If kidney cancer is suspected, your doctor will check your general health and will perform blood and urine tests. This may also include an examination of the abdominal area for lumps or masses. The doctor usually orders tests to picture the kidneys and nearby organs.

These may include:

• CT scan, Magnetic Resonance Imaging (MRI) or ultrasound, which can show the presence of a tumor and help determine whether it is benign or malignant
• An intravenous pyelogram (IVP), a series of x-rays taken after a dye has been injected

If the diagnosis is still in doubt after the above tests, a biopsy may be done to check a sample of tissue under the microscope for cancer cells. If kidney cancer is found, the doctor will determine the stage of the disease in order to plan treatment. This may involve more MRI and x-ray studies of the tissues and blood vessels in and around the kidney. Arteriography, a series of x-rays of the blood vessels, may be done to help determine if it will be possible to remove only part of the kidney, or if the entire kidney will need to be removed. A chest x-ray can also help to show whether the cancer has spread to the lungs, and bone scans can reveal whether it has spread to the bones.

Treatment options for renal cancer

Treatment method depends on the stage of the disease, general health, age and other factors. A team of specialists including urologist, oncologist (cancer specialist) and a radiation oncologist may be called upon to treat renal cancer. Surgery, radiation therapy, biological therapy, chemotherapy or hormone therapy are the usual treatments for kidney cancer. Sometimes, a combination of methods may be used. Knowing which kind of cell a tumor is composed of helps doctors plan treatment.

Standard treatments available for kidney cancer include: 

• Surgery — The most common treatment for kidney cancer. Most often, the whole kidney is removed along with the adrenal gland and the tissue around the kidney. Some lymph nodes in the area may also be removed. The remaining kidney is usually able to perform the work of both kidneys. In some cases, the surgeon only removes the part of the kidney that contains the tumor.
• Arterial embolization — This procedure is sometimes done before surgery to make the operation easier. A special gelatin sponge material is injected through a plastic tube to clog the main kidney blood vessel. This shrinks the tumor by taking away the oxygen-carrying blood and other substances it needs to grow. 
• Radiation Therapy — A treatment using high-energy rays to kill cancer cells. Doctors may use this to relieve pain when kidney cancer has spread to the bone. Most often, this treatment is given on an outpatient basis in a hospital or clinic five days a week for several weeks. 
• Biologic Therapy — Also called immunotherapy. It is a form of treatment that uses the body’s natural ability (immune system) to fight cancer. Interleukin-2 and interferon are types of therapy used to treat advanced kidney cancer. Many people having biologic therapy stay in the hospital during treatment so that the side effects can be monitored.
• Chemotherapy — The use of drugs to kill cancer cells. Although useful in the treatment of many other cancers, chemotherapy has shown only limited effectiveness against kidney cancer.
• Hormone Therapy — Used in a small number of patients with advanced kidney cancer. Some kidney cancers may be treated with hormones to try to control the growth of cancer cells.

Conclusion

Any cancer diagnosis is scary. Kidney cancer can be made even more challenging if complicated by kidney disease and dialysis treatment. Renal cancer, in a great number of cases, may be fully cured with early detection and treatment. Talk to your doctor if you have questions about the risk of kidney cancer.

Learn more about kidney cancer

You can learn more about kidney cancer, including the relationship between kidney cancer and kidney disease or hemodialysis at the following websites:

Cancer Organizations

• Kidney Cancer Association  
  Publications, patient meetings, annual patient conferences, online
  support (chat, message board), videos, newsletter: Kidney Cancer News.
  Call 1-800-850-9132
• 
  Educational programs and support group information through network of local offices. Materials include booklets, videos, and audiotapes; many also available in Spanish.
  Call 1-800-ACS-2345.
• 
  Publications include Teamwork: The Cancer Patient’s Guide to Talking with Your Doctor, and an audio program for patient empowerment: Cancer Survival Toolbox.
  Call 1-877-622-7937.