If kidney cancer is diagnosed, your doctor needs to learn the extent (stage) of the disease to help you choose the best treatment. The stage is based on the size of the kidney tumor and whether the cancer has invaded nearby tissues or spread to other parts of the body.
Your doctor may order one or more tests:
- Blood tests: Your doctor can check for substances in your blood. Some people with kidney cancer have high levels of calcium or LDH. A blood test can also show how well your liver is working.
- Chest x-ray: An x-ray of the chest can show a tumor in your lung.
- CT scan: CT scans of your chest and abdomen can show cancer in your lymph nodes, lungs, or elsewhere.
- MRI: MRI can show cancer in your blood vessels, lymph nodes, or other tissues in the abdomen.
When cancer spreads from its original place to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the primary (original) tumor. For example, if kidney cancer spreads to a lung, the cancer cells in the lung are actually kidney cancer cells. The disease is metastatic kidney cancer, not lung cancer. It’s treated as kidney cancer, not as lung cancer. Doctors sometimes call the new tumor “distant” disease.
These are the stages of kidney cancer:
- Stage I: The tumor is no bigger than a tennis ball (almost 3 inches or about 7 centimeters). Cancer cells are found only in the kidney.
- Stage II: The tumor is bigger than a tennis ball. But cancer cells are found only in the kidney.
- Stage III: The tumor can be any size. It has spread to at least one nearby lymph node. Or it has grown through the kidney to reach nearby blood vessels.
- Stage IV: The tumor has grown through the layer of fatty tissue and the outer layer of fibrous tissue that surrounds the kidney. Or cancer cells have spread to nearby lymph nodes or to the lungs, liver, bones, or other tissues.