Understanding Your Grade and Stage of Kidney Cancer
If you have kidney cancer, you may have a kidney biopsy and other tests. These will help your doctor determine:
What the cancer cells look like under a microscope, known as the grade of the cancer
The size of the tumor and how far the disease has spread, known as the stage of the cancer
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. The Furhman scale, which is 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 American Joint Committee on Cancer (AJCC) TNM System is a standard system for describing the extent of a cancer’s growth. 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 four stages of kidney cancer:
Stage I. The cancer is found only in the kidney, and it is 7 centimeters (cm) (about 2.75 inches) or less in diameter.
Stage II. The cancer is found only in the kidney, and the tumor is greater than 7 cm in diameter.
Stage III. In this stage, one of the following is true:
Cancer is in the kidney and has spread to one or more nearby lymph nodes. (Lymph nodes are small bean-shaped structures that are found throughout the body. They produce and store infection-fighting cells.) The cancer has not spread to distant lymph nodes or distant organs.
Cancer has grown into the main blood vessels of the kidney or the large vein that the kidneys drain into, known as the vena cava. It may be growing into nearby tissue, but has not spread to any lymph nodes or into the adrenal gland.
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. Cancer may have also spread to the adrenal gland, which is attached to the top of the kidney. The cancer may also be in nearby lymph nodes but has not spread to distant lymph nodes or organs.
The cancer has spread to distant lymph nodes and/or other organs, such as the bowel, pancreas, or lungs. It may also be found in nearby distant 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.