The fecal Occult Blood (FOB) test looks for hidden (occult) blood in your stool (fecal matter). Hidden blood is sometimes a sign of polyps (growths) in your colon that may turn into cancer. Completing this test is important because even if you have a polyp, you may never feel symptoms—only screening can detect it. If blood is found in your stool through this test, you will be recommended to have a colonoscopy.
The fecal occult blood test (FOBT) is a lab test used to check stool samples for hidden (occult) blood.
Occult blood in the stool may indicate colon cancer or polyps in the colon or rectum — though not all cancers or polyps bleed.
Typically, occult blood is passed in such small amounts that it can be detected only through the chemicals used in a fecal occult blood test.
If blood is detected through a fecal occult blood test, additional tests may be needed to determine the source of the bleeding. The fecal occult blood test can only detect the presence or absence of blood — it can't determine what's causing the bleeding.
The fecal occult blood test is one option for colon cancer screening. It may be an option if you have an average risk of colon cancer and don't have any symptoms. The fecal occult blood test is typically repeated yearly.