Symptoms of Colon Cancer

What to Watch For and Why

Colon cancer
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Symptoms are those niggling little indicators that all may not be well within your body. The symptoms of colon cancer are a vague collection of gastrointestinal complaints that could be indicative of any number of other, less-serious health concerns -- even gas or an overindulgence of your favorite food. Most symptoms of colon cancer appear after the cancer has already grown, which is why discussions about colon cancer symptoms usually include the topic of screening.

Why is Screening So Important?

Colon health screening tests, such as checking for blood in the stool or colonoscopies, facilitate the potential to find any unhealthy conditions within your colon before they become cancerous. If you are 50 or older, have positive gene typing or conditions that increase your genetic risk of cancer, such as familial adenomatous polyposis (FAP), Medicare will cover preventive screening tests. Most private insurance companies will cover the cost also, but be sure to check with your provider beforehand to avoid any sticker shock after your test.

Colon cancer symptoms may be representative of where the cancer is growing inside the colon. However, you can have colon cancer without experiencing any signs or symptoms of the disease. The most common symptoms associated with colon cancer are:

  • A change in bowel habits
  • Blood in the bowel movements
  • Thin, ribbon-like bowel movements
  • Inexplicable weight loss
  • Feeling tired all the time
  • Loss of appetite
  • Pain in the stomach
  • Unexplained bloating, gas and fullness
  • Nausea or vomiting

Although you don't want to become obsessed with your toileting habits, it is important to recognize changes. Did that occasional bout of diarrhea turn into a prolonged bowel habit change?

Do you normally produce one or two bowel movements daily or every other day? Know what your "normal" bowel habits are, because they are different for everyone.

Deviations of normal bowel habits should be watched. The occasional bout of diarrhea or constipation may be normal based on dietary changes or not drinking enough fluids. When diarrhea or constipation occur over days, weeks, or months, it is considered a chronic change.

Bloody bowel movements indicate a problem. It could be a small, uncomfortable problem, such as a hemorrhoid, or a more serious condition, such as bleeding polyps. Whether the blood is fresh and bright red or old and dark red or black, bleeding from the rectum is not normal.

Ribbon-like stools sometimes occur when tumors obstruct the passage of stool. An obstruction is a blockage -- either partial or complete -- of the pathway for stool.

Abdominal pain or pain occurring anywhere in your trunk indicates a problem. Take note of the pain and try to detail the exact locations, severity, duration and a description for your doctor.

The words you associate with your pain are important. A deep gnawing pain may mean something completely different than a sharp, lightening-like pain.

Bloating and a feeling of fullness may be normal occurrences after a Thanksgiving dinner, but not on a daily basis. Bloating may sometimes cause gas and can become a very uncomfortable symptom.

Fatigue, or feeling inexplicably tired all of the time, is one of the most ambiguous symptoms of colon cancer. Literally hundreds of medical conditions come with a symptom of fatigue; it does not automatically suggest cancer. You could be overextended between familial, social and work responsibilities. Only you know your normal energy level and its deviations.

Nausea, vomiting, or lack of an appetite can indicate a gastrointestinal problem. The occasional bout of nausea and vomiting may be associated with a stomach bug, but are not normal conditions in the otherwise healthy person.

Inexplicable weight loss should be discussed with your doctor. There are many simple and not-so-simple problems associated with losing weight for no reason.

If you suffer one or more of these symptoms, take care of your emotional and physical well-being by talking to your doctor. He or she will be able to point you in the right direction for screening exams, which are fairly simple tests to rule out or find problems in your colon. Depending on your insurance coverage, they may not cost you a penny, but will be worth their weight in gold if they can provide peace of mind that you do not have colon cancer or a recurrence of cancer.


American Cancer Society. (2008). Colorectal Cancer. What You Need to Know - NOW. Atlanta: American Cancer Society Health Promotions.

Centers for Disease Control and Prevention. (n.d.). Colorectal (Colon) Cancer: Insurance and Medicare. Accessed: October 27, 2011.

Rex, D.K. & Liangpunsakul, S. (2007). Colorectal Cancer Screening. American College of Gastroenterology. Accessed: October 27, 2011.

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