Cancer Staging and Grading

Following a diagnosis of cancer, an important next step is to accurately determine the stage of the cancer. Staging is a system that describes how far the cancer has spread.

Different stages of cancer may be treated differently. That's why, in order for you to discuss treatment options with your health care team, you need to know the correct stage of your cancer.

It is important to know, however, that some cancers are not staged. Talk with your doctor about your specific case. And be sure to keep track of your diagnostic results with Tools for Organizing Your Cancer Information.

TNM Staging

Grading the Aggressiveness of Cancer

There are many staging systems but TNM Staging is the most common to measure the extent of the spread of cancer:

 

T

"T" refers to the size of the tumor.

N "N" refers to the number of lymph nodes involved.
M "M" refers to metastasis.
STAGES: Generally the lower the stage, the better the treatment prognosis (prediction of the result):
0 Precancer
1 Small cancer found only in the organ where it started
2 Larger cancer that may or may not have spread to the lymph nodes
3 Larger cancer that is also in the lymph nodes
4 Cancer in a different organ from where it started
*Example: T1N0M0

Grading is the system that describes the aggressiveness of cancer cells. When doctors look at cancer cells under the microscope, they compare them with normal cells. The more cancer cells differ from normal cells in appearance, the higher the grade. The American Joint Commission on Cancer (AJCC) recommends the following grading system:

 

GX Grade cannot be assessed
G1 Well-differentiated - the cancer cells look fairly normal
G2 Moderately differentiated - the cells are less normal in appearance but still have some recognizable structures
G3 Poorly differentiated - the cells have a pattern very different from normal cells
G4 Undifferentiated - the cells are in a completely unrecognizable pattern

 

Courtesy of: Mayo Clinic