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.
Jun. 18, 2011
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- Fletcher RH. Tests for screening for colorectal cancer: Stool tests, radiologic imaging and endoscopy. http://www.uptodate.com/home/index.html. Accessed April 12, 2011.
- Labianca R, et al. Screening and diagnosis for colorectal cancer: present and future. Tumori. 2010;96:889.
- American Cancer Society guidelines for the early detection of cancer. American Cancer Society. http://www.cancer.org/docroot/PED/content/PED_2_3X_ACS_Cancer_Detection_Guidelines_36.asp?sitearea=PED. Accessed April 12, 2011.
- Lieberman D. Progress and Challenges in Colorectal Cancer Screening and Surveillance. Gastroenterology. 2010;138:2115.
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- Doppler JM (expert opinion). Mayo Clinic, Rochester, Minn. June 8, 2011.