Cancer of the colon or rectum is often called colorectal cancer. The colon and the rectum are part of the large intestine, which is part of the digestive system. Colorectal cancers are the third most common type of cancer in men and women.

Risk factors for colorectal cancer

Studies have found that certain factors may increase the risk of getting colorectal cancer. These factors include:

  • Being over the age of 50
  • A history of colon polyps (small non-cancerous growths)
  • Family history of colon cancer
  • A high-fat, low-fiber diet
  • Inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
  • Daily drinking of alcoholic beverages
  • An inactive lifestyle

Possible signs & symptoms of colorectal cancer

  • Change in bowel habits (used to have one bowel movement a day, now two to three)
  • Blood in the stool, dark or bright red
  • Fatigue
  • Stools that are narrower than usual
  • Abdominal pains such as gas pains, cramping, bloating
  • Loose or watery bowel movements or hard stools that are difficult to pass for more than two weeks
  • Feeling as if the bowel isn’t completely emptying

Screening tests for colorectal cancer

There are five screening tests for colorectal cancer. Talk with your doctor about which tests are right for you. The five screening tests are:

  • Digital rectal exam: The doctor gently inserts a gloved, lubricated finger into the rectum and feels for abnormal areas.
  • Fecal occult blood test: Samples of stool are tested for blood that is not visible to the eye. Blood can be a sign of polyps, other benign conditions or cancer.
  • Sigmoidoscopy: The doctor inserts a small, flexible, lighted tube into the rectum and lower colon to inspect up to 25 inches of the lower bowel. Polyps can be easily removed during this exam.
  • Colonoscopy: The doctor inspects the entire colon with an instrument similar to a sigmoidoscope, but longer. Any polyps or suspicious growths can be removed during this exam.
  • Barium enema with air contrast examination: For this exam, barium sulfate, a chalky substance that shows up on X-rays, is given in enema form. X-rays are then taken of the colon. To make small tumors easier to see, the doctor may carefully pump in air to expand the colon.

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