Stages of Renal Cell Cancer

After renal cell cancer has been diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other parts of the body.

The process used to find out if cancer has spread within the kidney or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. The following tests and procedures may be used in the staging process:

• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the chest or brain, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the brain. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
• Bone scan: A procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones with cancer and is detected by a scanner.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

• Tissue. The cancer spreads from where it began by growing into nearby areas.
• Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
• Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

• Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
• Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if renal cell cancer spreads to the bone, the cancer cells in the bone are actually cancerous renal cells. The disease is metastatic renal cell cancer, not bone cancer.

The following stages are used for renal cell cancer:

Stage I

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

Stage II

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

Stage III

In stage III, one of the following is found:

• the cancer in the kidney is any size, and cancer has spread to nearby lymph nodes; or
• cancer has spread to blood vessels in or near the kidney (renal vein or vena cava), to the fat around the structures in the kidney that collect urine, or to the layer of fatty tissue around the kidney. Cancer may have spread to nearby lymph nodes.

Stage IV

In stage IV, one of the following is found:

• cancer has spread beyond the layer of fatty tissue around the kidney and may have spread into the adrenal gland above the kidney with cancer or to nearby lymph nodes; or
• cancer has spread to other parts of the body, such as the bones, liver, lungs, brain, adrenal glands, or distant lymph nodes.

Renal cell cancer can recur (come back) many years after initial treatment.

The cancer may come back in the kidney or in other parts of the body.