Fecal occult blood tests in the United States have been called the “Rodney Dangerfield” of choices for colorectal cancer screening. Why? “They just don’t get no respect.” They, should, however, get more credit and attention.
The available FOBT tests are the guaiac test (GT) and the immunochemical test (FIT).
The standard GT has been studied extensively and remains the only colorectal cancer screening test shown by randomized controlled studies to decrease mortality and incidence of colon cancer.
The person screened is required to collect a stool sample in the dry state and to sample the feces with a wooden stick. These requirements limit patient acceptance. For instance, a group of motivated volunteers in an Australian population where red meat consumption is relatively high, a restrictive diet reduced participation by 13 percent.
The standard GT is currently in use in the United Kingdom and Ontario, Canada as the test of choice for population screening programs. The U.S. Preventive Services Task Force guidelines do not recommend this test, but do say if a GT is to be used, it should be the sensitive GT Hemoccult Sensa.