How can I tell if my colon cancer is gone after surgery?

After the segment of your colon containing the cancerous tumor is taken out during surgery, it is submitted for pathological analysis. During this process a pathologist examines the specimen and lymph nodes under a microscope to determine if the tumor has been completely removed, and whether or not the tumor has spread to the nearby lymph nodes. This process is called tumor staging.

If after pathological analysis the segment of your colon which was taken out contains the entire tumor, without spread to the surrounding lymph nodes, then you are considered to be free of cancer. (this is assuming that you had the required preoperative workup which determined that you did not have distant spread of your tumor referred to as metastatic disease).

Of course to ensure that your cancer does not return you will need periodic follow up in the form of physical exams, blood work, and colonoscopy.