Although grading and the identification of cancer cell types help determine a patient's prognosis, most doctors believe that the most important factor in predicting prognosis, as well as the treatment options, is the "stage" of the cancer. Staging is the process of gathering information from physical examinations and diagnostic tests to determine the size and location of the tumor and how widespread a cancer is. Diagnostic tests include imaging studies such as CT scans and MRIs.
The treatment and prognosis for renal cell carcinoma will depend significantly on its stage. There are two common staging systems for RCC, the TNM System (include TNM info below as a pop-up window) and the University of California Los Angeles Integrated Staging System (UISS) System. (include UISS info below as a pop-up window) The Fuhrman Grading System is a system used to describe how kidney tumors appear under the microscope. (include Furhman info below as a pop-up window)
TNM Staging System The most commonly used staging system is that of the American Joint Committee on Cancer (AJCC), also known as the TNM Staging System. The TNM (tumor-node-metastasis) system uses stages generally similar to those of the Robson system and is becoming more widely accepted because it provides a more detailed description of the tumor(s).
Primary Tumor Stage (T Stage) |
Graphic Representation |
Description |
T1 < 4 cm: T 1a |
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Tumor is confined to the kidney (no penetration through the capsule) and is no greater than 7 cm in dimension. |
T2 |
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Tumor is confined to the kidney (no penetration through the capsule) and is greater than 7 cm in dimension |
T3a |
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Tumor penetrates through the kidney capsule into the surrounding fat or the adrenal gland, but not through Gerota's fascia. |
T3b or T3c |
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Tumor extends into the renal vein or into the vena cava. (T3b indicates that the tumor thrombus does not extend above the level of the diaphragm. T3c indicates that the tumor thrombus extends above the level of the diaphragm.) |
T4 |
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Tumor penetrates through Gerota's fascia. |
Regional Lymph Nodes |
Description |
N0 |
No cancer in the lymph nodes |
N1 |
Cancer in a single lymph node |
N2 |
Cancer in more than one lymph node |
Distant Metastasis |
Description |
M0 |
No metastasis |
M1 |
Distant metastasis present |
The UCLA Integrated Staging System (UISS), developed by translational researchers within the UCLA Department of Urology, is a more complex but probably more accurate system that incorporates the TNM staging systems, a person's overall health and the Fuhrman grade of the tumor.
In the UISS system: Patients without any tumor spread are divided into three groups: low risk, intermediate risk and high risk.
The most recent five-year cancer-specific survival data for the low risk group is 91%, for the intermediate risk group is 80%, and for the high risk group is 55%.
Patients with tumor spread, to lymph nodes or distance sites such as bone, lung or liver, are also divided into these three groups. Low risk patients have a tumor that is T1-3, N1, M0. High risk patients have a T4 tumor, poor health and high Fuhrman grade or distant spread. Intermediate grades are all others. The five-year cancer-specific survival is lower in these people whose tumors have spread: for the low risk group it is 32%, for the intermediate risk group 20% and for the high risk group 0%.
Another important factor used by doctors in assessing renal cell carcinoma is its Fuhrman grade (named after the pathologist who developed the system). This refers to how closely the cancer cells look like normal kidney cells under a microscope.
The Fuhrman grading system ranks tumor cells on a scale of 1 through 4.
Grade 1 tumor cells don't look very different from normal kidney cells. Grade 1 cancers typically grow and spread slowly and most often have a good prognosis. On the other hand, Grade 4 tumor cells look quite different from normal kidney cells and have a worse prognosis.