What can I do to prevent colorectal cancer? What are the screening tests for this type of cancer?

Colorectal cancer can be prevented by getting screening tests once you reach age 50. These tests look for polyps and early signs of cancer. Some of the tests can remove polyps at the same time. Talk with your health care provider about what tests are best for you and how often you should get them. If you have a family history of colorectal cancer or other special conditions, your doctor may suggest starting screening tests before age 50.

Screening tests and recommendations for how often you should have each test include:

• Fecal occult blood test (FOBT) - checks for hidden blood in the stool. Sometimes cancers or polyps can bleed and this test is used to pick up small amounts of bleeding. Have this test every year.
• Flexible sigmoidoscopy - an exam where a health care provider looks at the rectum and the lower part of the colon using a sigmoidoscope, a tube with a light on the end. Have this test every 5 years.
• Colonoscopy - an exam when a health care provider looks at the rectum and the entire colon using a colonoscope, an instrument with a light on the end. If polyps are found, they can be removed. Have this test every 5 to 10 years.
• Double contrast barium enema (DCBE) - a series of x-rays of the colon and rectum. You are first given an enema with barium in it, which outlines the colon and rectum on the x-rays. Have this test every 5 to 10 years (only if not having a colonoscopy every 10 years).
• Digital rectal exam - a health care provider inserts a lubricated, gloved finger into the rectum to feel for any problem areas. Have this test every 5 to 10 years at the time of other screening tests (flexible sigmoidoscopy, colonoscopy, or DCBE).

Other things you can do to help prevent colorectal cancer include:

• Have a healthy diet low in fat and high in fiber, with plenty of fruits and vegetables. Researchers are looking at foods rich in folate (the natural form of folic acid), such as leafy green vegetables and fortified cereals, for how they may help reduce a person's risk for colorectal cancer. Adding these foods to your diet or taking a daily multivitamin with 0.4 mg of folic acid may help.
• Get regular exercise (30 minutes per day most days of the week).
• Lose weight if you are overweight (obese).
• Limit alcohol intake and do not smoke or use tobacco products.

Some studies have shown that using nonsteroidal anti-inflammatory drugs (NSAIDs) may help reduce a person's risk for colorectal cancer. For women, using hormones after menopause may decrease the risk for colon (but not rectal) cancer. New research shows that some pain medications called COX-2 inhibitors may also help to prevent colon cancer. Other studies are looking at stopping smoking, taking aspirin each day, decreased alcohol intake, and increased physical activity to see if they can prevent colorectal cancer.