ResultsBy Mayo Clinic staff
Your doctor will review the results of the fecal occult blood test and then share the results with you.
- Negative result. A fecal occult blood test is considered negative if no blood is detected in your stool samples. If you had the test to screen for colon cancer and you're at average risk — you have no colon cancer risk factors other than age — your doctor may recommend waiting one year and then repeating the test.
- Positive result. A fecal occult blood test is considered positive if blood is detected in your stool samples. You may need additional testing — such as a colonoscopy — to locate the source of the bleeding.
It's important to remember that false-negative and false-positive results are possible. Some cancers and most polyps don't bleed, which may lead to a false-negative result. Likewise, occult bleeding may come from sources other than colon cancer or a polyp — a false-positive — such as from a stomach ulcer, hemorrhoid, or even blood swallowed from your mouth or nose.
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- Doppler JM (expert opinion). Mayo Clinic, Rochester, Minn. June 8, 2011.