You know those “You are here” markers on maps? Colorectal cancer staging works a lot like that.

Cancer staging is one way to determine if, and/or how far, your cancer has spread. Your stage explains where the cancer cells have gone.

There are two phases for cancer staging: a clinical stage and a pathological stage.

Around 80% of the time, the clinical stage is aligned with the pathological stage. But 20% of the time, the cancer stage changes once pathology reports from colon cancer surgery have come in. Typically, this occurs in early-stage cancers—when a clinical stage indicates stage I or II, but pathology shows the cancer has spread to areas the imaging didn’t show. The pathologic change is considered most accurate in patients where surgery is the first type of cancer treatment delivered.

With rectal cancer, sometimes it’s preferable not to perform surgery immediately but instead to start with chemotherapy, immunotherapy, and/or radiation therapy. When this is the case, doctors primarily rely on scans to help determine stage.

From the patient experience, it will seem as though your cancer stage can change, especially in cases where cancer recurs or metastasizes to other parts of the body. For example, it’s possible to be diagnosed initially with stage II colon cancer but have it spread to surrounding organs, and therefore upstaging you to stage IV—metastatic colorectal cancer.

Don’t be surprised if your provider says that the extent of disease at or around the time of your diagnosis stays with you forever. So, if you have cancer in the lymph nodes at the time of diagnosis and develop lung metastases, your paperwork may show you have stage III disease with recurrence in the lungs. The stage III at diagnosis remains the stage in the databases, and it’s considered recurrent cancer.

HOWEVER: If your cancer has metastasized and you’re looking for clinical trials and planning treatment, consider yourself a stage IV patient and look for clinical trials for stage IV cancer – even if you had an earlier stage at diagnosis.

The surgical pathology report may tell you the tumor, node, and metastasis (TNM) classification of your tumor.

The American Joint Committee on Cancer (AJCC) developed and continues to update the TNM system, which scores your tumor in each of these areas. The score is used to determine your pathological stage of cancer :

Based on your TNM score, you will receive a stage 0, stage I, stage II, stage III, or stage IV diagnosis. Sometimes a, b, and c are added to your cancer stage to further subclassify the stage of the tumor as well, which is also determined by the TNM score.

Each cancer gets its own stage. Some patients are considered cured (or they are classified as having NED: no evidence of disease) of a cancer only to have a second cancer appear years later. (A cancer that was not a recurrence from their first cancer, but a new and separate cancer, which is called a primary tumor.) In this instance, the subsequent cancer receives its own stage, which will play a role in determining treatment plans. Subsequent cancers are not necessarily stage IV cancers—sometimes these cancers are caught in early stages and patients do not need treatment outside of surgery.

The development of more than one colon cancer in the same person is especially common in patients with genetic syndromes that predispose them to the development of colorectal and other cancers, such as Lynch syndrome, FAP, or other inherited polyposis syndromes.

Yes! There are survivors from every stage of colorectal cancer, and many of them have shared their stories in our Champion Stories hub to encourage you. Browse their stories and words of encouragement, and don’t forget to add your own when you’re ready.