Kidney Cancer: Grade and Stage

What does the stage and grade of a cancer mean?

The stage of a cancer is how much and how far the cancer has spread in your body. Your healthcare provider uses exams and tests to find out the size of the cancer and where it is. He or she can also see if the cancer has grown into nearby areas, and if it has spread to other parts of your body.

The grade refers to how the cancer cells look when compared to normal kidney cells. The grade of your cancer will help your healthcare provider predict how fast the cancer may grow and spread. The Furhman scale of 1 to 4 is used to grade kidney cancer. The lower the number, the more the cancer cells look like normal cells and cancer cells that look more like normal cells tend to grow and spread slowly. This means the cancer can be easier to treat and cure. Grade 4 cancer look very different from normal kidney cells. This grade of cancer is harder to treat.

Staging and grading of cancer is important for deciding how to treat it, and how curable it is.

The TNM system for kidney cancer

The most commonly used system to stage kidney cancer is the TNM system from the American Joint Committee on Cancer (AJCC). Be sure to ask your healthcare provider to explain the stage of your cancer to you in a way you can understand.

The first step in staging is to find the value for each part of the TNM system. Here's what the letters stand for in the TNM system:

• T tells how far the main tumor has spread inside your kidney and into nearby tissue.

• N tells if the lymph nodes in the area of the original tumor have cancer in them.

• M tells if the cancer has spread (metastasized) to distant organs in the body, such as the liver, lung, bones, or brain.

Numbers or letters after T, N, and M provide more details about each of these factors. There are also two other values that can be assigned:

• X means the provider does not have enough information to tell the extent of the main tumor (TX), or if the lymph nodes have cancer cells in them (NX).

• 0 means no sign of cancer, such as no sign of spread to the lymph nodes (N0).

What are the stage groupings of kidney cancer? 

Stage groupings are determined by combining the T, N, and M values from the TNM system. These groupings give an overall description of your cancer. A stage grouping is listed as a Roman numeral and can have a value of I through IV (1 through 4). The higher the number, the more advanced the cancer is. Letters and numbers can be used after the Roman numeral to give more details.

These are the stage groupings of kidney cancer and what they mean:

Stage I. The cancer is found only in the kidney. It is 7 centimeters (cm) (about 2.75 inches) or less in diameter.

Stage II. The cancer is found only in the kidney. The tumor is larger than 7 cm in diameter.

Stage III. The cancer hasn't spread to distant parts of the body and one of the following is true:

• The cancer may have spread outside the kidney, but it hasn't spread beyond Gerota’s fascia (a thin sac that covers each adrenal gland and kidney). It has spread to nearby lymph nodes, but not to other organs or distant parts of the body.

• Cancer has grown into a large vein or into nearby tissue, but it's not in the adrenal gland or beyond Gerota's fascia. It has not spread to any lymph nodes or to distant organs.

Stage IV. One of the following is true:

• The cancer has spread outside Gerota's fascia. Cancer may have spread to the adrenal gland on top of the kidney. The cancer may or may not be in nearby lymph nodes. It has not spread to distant lymph nodes or organs. 

• The cancer has grown outside the kidney. It has spread to distant lymph nodes or other organs. These may include bones, liver, brain, or lungs. It may also be found in nearby lymph nodes.

Talking with your healthcare provider

When your cancer is staged, talk with your healthcare provider about what the stage means for you. Make sure to ask questions and talk about your concerns.