You may have a kidney biopsy and other tests. These will help your doctor determine:
What the cancer cells look like under a microscope, called the grade of the cancer
The size of the tumor and how far the disease has spread, called its stage
Kidney cancer may be localized to one area but can spread to other parts of your body. Your treatment plan and prognosis depend on the stage and grade of your kidney cancer and other factors, such as your age and general health.
Grades of Kidney Cancer
The grade of your cancer is the terminology doctors use to describe how the cancer cells look. Knowing how the cells look will help your doctor predict how fast the cancer may grow and spread. Specifically, the grade refers to how the part of the cell where DNA is stored, called the nucleus, looks compared to normal kidney cells’ nuclei. A scale of 1 to 4 is usually used to grade kidney cancers. The lower the number, the closer the cancer cells look like normal cells and the better the outlook, called the prognosis. That’s because these cancers tend to grow and spread slowly. On the other hand, cancers with a grade 4 look very different from normal kidney cells. They have a worse prognosis.
Stages of Kidney Cancer
The stage of your cancer is the terminology doctors use to communicate the size of a tumor and where and how deeply it has spread. When you are diagnosed with kidney cancer, the doctor needs to know the type of kidney cancer you have and the stage the cancer is in.
The TNM System is a standard system for describing the extent of a cancer’s growth. The International Union Against Cancer and the American Joint Committee on Cancer developed this system. Here’s what the letters stand for in the TNM System:
T tells how much a tumor has spread into your kidneys and nearby areas.
N tells whether the lymph nodes in the area of the original tumor have become cancerous, and if so, how many.
M tells whether the cancer has spread to other, distant organs in the body, such as your lung, bones, or lymph nodes that are not near your kidneys.
Numerical values, from X to 3, are assigned to the T, N, and M categories. Once your oncologist has determined your T, N, and M stages, this information is put together in what is called stage grouping. Stage grouping is used to determine your overall disease stage. It is expressed in Roman numerals from I (the earliest stage) to IV (the most advanced stage). Here are the 4 stages of kidney cancer.
Stage I. The cancer is found only in the kidney, and it is 7 centimeters or less in diameter.
Stage II. The cancer is found only in the kidney, and the tumor is greater than 7 centimeters in diameter.
Stage III. In this stage, one of the following is true.
Cancer is in the kidney and in one nearby lymph node. (Lymph nodes are small bean-shaped structures that are found throughout the body. They produce and store infection-fighting cells.)
Cancer is in an adrenal gland or in the layer of fatty tissue around the kidney. (The adrenal gland, which is attached to the top of the kidney, produces certain hormones.) It may also be in one nearby lymph node.
Cancer is in the main blood vessels of the kidney or the large vein that the kidneys drain into, known as the vena cava. It may also be in one nearby lymph node.
Stage IV. In this stage, one of the following is true.
The cancer has spread outside the connective tissue covering of the kidney, known as Gerota’s Fascia.
The cancer has spread to 2 or more nearby lymph nodes.
The cancer has spread to other organs, such as the bowel, pancreas, or lungs. It may also be found in nearby lymph nodes.
Recurrent. Recurrent cancer has come back after it has been treated. It may come back in the original area or in another part of the body.