Types of Screening Tests
A doctor may recommend that you have a Hemoccult (fecal occult blood test, or FOBT) test every year if you are at least fifty years old. This involves sending in a small stool sample, which is checked by a laboratory for hidden blood. The test is simple and quick, but it is not the most accurate method for diagnosing colorectal cancer.
More about the Hemoccult test.
A colonoscopy checks your entire large intestine for cancer and polyps. It is a very effective test that prevents cancer by removing any polyps that are found. Almost all patients are sedated during the procedure, and will need to have someone drive them home. Most patients are at the hospital for about three hours.
More about colonoscopy.
This test is similar to a colonoscopy, except that it only looks at the lower portion of the large intestine and the rectum, instead of the entire large intestine. The test only takes a few minutes, but as with a colonoscopy, you need to do some preparation beforehand to clean out your large intestine.
More about flexible sigmoidoscopy.
Air Contrast Barium Enema
Barium is a white substance that allows problem areas of the large intestine to show up on an X-ray. You will be given an enema containing barium before the X-ray. The large intestine appears as a white image, while any growths in the intestine will show up as dark areas.