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Colon cancer screenings

Nobody enjoys a colonoscopy. First, there’s the dreaded fasting and the preparation, which empties out your bowels. Then comes the actual procedure, the mere thought of which scares some people into avoiding the test altogether. But colon cancer screenings save lives. The earlier cancer is found, the better your shot of surviving.

Colonoscopies are the gold standard for detecting—and removing—precancerous cells and cancerous growths. But there is a wide range of options for colon-cancer detection:

  • Digital rectal exam. A lubricated, gloved finger is inserted into the lower part of the rectum to feel for growths.
  • Fecal occult blood test. This test checks stool for blood that can only be detected with a microscope. Your healthcare provider usually gives you a home collection kit, which may involve smearing a sample on a specially treated card or using flushable pads that detect blood in bowel movements and don’t require stool collection.
  • Flexible sigmoidoscopy. For this test, a small, flexible scope mounted with a camera looks at the lower part of the colon (as compared to the entire colon, which a colonoscopy can see). The scope may also have a tool that removes polyps or gathers tissue samples, to be evaluated under a microscope. Because it only looks at the lower colon, sigmoidoscopy can miss some cancers. Experts recommend that it be done with the stool test.
  • Barium enema. This is a series of lower gastrointestinal tract X-rays. A liquid containing barium is put into the rectum before X-rays are taken.
  • Colonoscopy. A colonoscope—a thin, tubelike instrument with a light and a camera—is inserted into the rectum and used to examine the entire length of the colon. The colonoscope may also have a tool that removes polyps or tissue samples, which are then evaluated.
  • Virtual colonoscopy. In this test, a series of X-rays are taken to create images of the colon. It can show polyps and other abnormalities and is less invasive than a standard colonoscopy, but if any suspicious lesions are found, you’ll have to undergo a traditional colonscopy to confirm the findings.