About Colorectal Cancer
The stage of your cancer is one of the most important factors in determining the best treatment option for you.
Staging of Colorectal Cancer
TNM is the staging system for colorectal cancer. "T" stands for tumor size, "N" is for lymph nodes and "M" is for metastasis.
- Tumor size is determined when the tumor is removed and sent to the pathologist.
- Lymph nodes are checked for evidence of tumor spread with CT scans, PET scan, lymph node biopsy or at the time of surgery in a procedure called lymph node dissection.
- Metastasis (spread to other organs) is assessed with bone scans, x-rays and CT scan. Putting all this information together is called staging.
Stages for colorectal cancer range from Stage 0 to Stage IV.
There are really two types of staging for colorectal cancer. The clinical stage is your doctor’s best guess of the extent of your disease, based on the results of the physical exam, biopsy and any other tests you have had. If you have surgery, your doctors can also figure out the pathologic stage. This stage is based on the same factors as the clinical stage plus what is found during surgery and a biopsy of the tissue.
Because most patients with colorectal cancer have surgery, the pathologic stage is most often used to describe the extent of this cancer. Pathologic staging is likely to be more accurate than clinical staging, as it allows your doctor to get a good look at the extent of your disease.
Grade of colorectal cancer
Another factor that can affect the outlook for survival is the grade of the cancer. Grade is a description of how closely the cancer looks like normal colorectal tissue under a microscope. Low-grade means the tissue looks more normal, high-grade means the tissue looks less normal. Most of the time, the outlook is not as good for high-grade cancers as it is for low-grade cancer.