What is Metastatic Colon Cancer?

Getting diagnosed with cancer is scary enough, but the fright factor exponentially increases as your doctor starts to use words that you may not understand like, "metastatic" or "aggressive". The word metastasis means that the colon cancer has spread somewhere else in your body -- it is no longer contained within the colon. A normal, healthy colon cell cannot move to another part of your body. You will not find a colon cell within your liver, for example, unless it is a cancerous cell that has traveled and spread cancer to the liver.

Types of Metastasis

Metastasis occurs locally, distally, or a combination of the two. It can spread nearby the colon, such as when the cancer in your colon breaks free and invades nearby tissues like the lining of your abdomen (peritoneum). Distal metastasis is when the cancer travels to organs well away from the colon, such as a metastasis to the liver, brain or lungs. Science has yet to discover the "whys" of this occurrence, but it is known that cancer cells can travel via your blood, lymph tissue, or through neighboring cellular walls. 

Staging Colon Cancer with Metastasis

The stage and grade of your colon cancer is usually associated with two things -- the treatment modalities available and your survival rate. It is less desirable to get diagnosed with metastatic colon cancer because it is more difficult to treat and the survival statistics are less favorable.

Stage III and stage IV colon cancers have metastasized to other sites.

Typically, stage III cancers are locally spread, whereas stage IV cancer has metastasized to distant sites, most frequently the liver.

Once you have been diagnosed with stage III or IV colon cancer, the stages do not downgrade with treatment and remission. For instance, if you started with stage III metastatic colon cancer but bowel surgery, chemotherapy and radiation eradicated all traces of it, you are not at a stage 0 now.

This is important to know for recurrence -- if your colon cancer returns, doctors may treat a stage I recurrence differently then they would treat a stage III recurrence.

How are the Metastatic Tumors Found?

You cannot detect metastasis with routine colon cancer screens, such as a colonoscopy. Although metastatic lesions may be found by accident, such as with an x-ray or computed tomography (CT) scan, this is not common. Following a biopsy of your colon cancer tissue the pathologist will note how mutated the cells appear, which is part of how the oncologist stages and grades your cancer. If your cancer has a high stage or grade, the oncologist will order further tests to see if the cancer has spread outside of the colon.

Treatment of Metastatic Cancers

The most common treatment modalities for metastatic cancer are surgery, chemotherapy, radiation, and targeted therapies, but they may not occur in that order. Your treatment will vary by the stage, grade and metastatic location. Working with you and the healthcare team, your oncologist might suggest chemotherapy or radiation prior to surgery to shrink the tumors.

He or she might also suggest different ways to administer the chemotherapy drugs, such as through the hepatic artery to treat liver metastasis.

Talk to your doctor and don't be afraid to ask questions if you do not understand. Ask the doctor what the treatment goals are: Is he or she trying to cure your cancer or simply palliate the symptoms? Knowing what to expect in advance of treatment can help you form more realistic expectations.

Statistics are Just Numbers

Although your doctor will provide the survival rates and other statistics regarding your specific cancer, just remember that these numbers don't define who you are. What the statistics are helpful for is to provide a framework of reasonable considerations best to treat your cancer.


American Cancer Society. (n.d.). Treatment by Stage of Colon Cancer. Accessed online November 23, 2013.

National Cancer Institute. (n.d.). Cetuximab Plus Oxaliplatin May Not Be Effective Primary Treatment for Metastatic Colon Cancer. Accessed November 25, 2013.

Continue Reading