A to Z Health Guide

How is Kidney Cancer Found?

How is kidney cancer found?

Kidney cancer is usually found by chance while being tested for other complaints.  The reason?  Because most people with early kidney cancer do not have symptoms.  Also, since the kidneys are deep inside the body, small kidney tumors may not be seen or felt during a routine physical checkup. Talk to your healthcare provider if you have a family history of kidney cancer or other risk factors.

If kidney cancer is suspected, your healthcare provider will check your general health and may do blood and urine tests. He or she may also feel the abdominal (stomach) area for any lumps. The doctor usually orders tests and images of the kidneys and nearby organs. These may include:

  • CT (computed tomography) scan with or without contrast.   CT scans use x-rays to take a complete picture (image) of the kidneys and abdomen (stomach area).  Small amounts of radiation are used.  A CT scan can often show if a growth appears cancerous or has spread beyond the kidney. 
  • MRI (magnetic resonance imaging) with or without contrast.  MRI scans also create a complete picture (image) of the kidneys and stomach area, but without using radiation.  It uses radio waves and strong magnets.  However, MRI can be more costly than CT scans, more time-consuming, and may not give pictures that are as clear as CT scan.
  • Ultrasound.  Ultrasound also gives you a complete picture (image) of the kidneys without using radiation.  It uses sound waves.  Ultrasound may be recommended if your healthcare provider is trying to figure out whether a mass in the kidneys is a fluid-filled cyst​ or a solid tumor. 
  • Biopsy.  A very small sample of kidney tissue is removed with a needle, and looked at under a microscope to see if cancer cells are present.  In most cases, a biopsy is not needed.  Instead, the diagnosis is usually based upon how the tumor looks on a CT scan, and confirmed when the tumor or entire kidney is removed during surgery.  

Not all kidney tumors are kidney cancers.  Many are benign (non-cancerous) and may not require treatment. 

What are the stages of kidney cancer?

Once kidney cancer is found, your healthcare provider will run tests to find out if the cancer has spread within the kidney or to other parts of the body. This process is called staging.  It is important to know the stage before making a treatment plan.  The higher the stage, the more serious the cancer.  There are four stages of kidney cancer:

Stage I

In stage I, the tumor is 7 centimeters or smaller and is found only in the kidney.

Stage II

In stage II, the tumor is larger than 7 centimeters and is found only in the kidney.

Stage III

  • Cancer is found in the main blood vessels of the kidney or in the layer of fatty tissue around the kidney; or
  • The tumor is any size and cancer is found only in the kidney and in one or more nearby lymph nodes

Stage IV

In stage IV, cancer has spread beyond the layer of fatty tissue around the kidney and may be found in the adrenal gland above the kidney with cancer, or in nearby lymph nodes; or to other organs, such as the lungs, liver, bones, or brain, and may have spread to lymph nodes.

See also:

What is Kidney Cancer?

Who is at Risk?

Treatments for Kidney Cancer

Talking with Your Healthcare Professional

The information shared on our websites is information developed solely from internal experts on the subject matter, including medical advisory boards, who have developed guidelines for our patient content. This material does not constitute medical advice. It is intended for informational purposes only. No one associated with the National Kidney Foundation will answer medical questions via e-mail. Please consult a physician for specific treatment recommendations.