HWN Suggests

FOBT of Fecal Samples: A Simple Colorectal Cancer Screening Tool

In summary, FOBT of fecal samples is a simple, non-invasive and affordable screening tool that can detect occult colorectal bleeding and reduce mortality from these potentially preventable cancers. It has high negative predictive value but positive results require colonoscopic confirmation. Repeated periodic screening is important for early detection. FOBT coupled with colonoscopy can improve outcomes in colorectal cancer screening programs.

read full article

Featured

 Guaiac-Based FOBTs vs. FITs for Colorectal Cancer Screening in Average-Risk Adults

Ideal gFOBT screening requires the collection of two fecal samples from three consecutive bowel movements, whereas FIT screening requires only one sample. FIT screening can provide quantitative results that allow for adjusting cut-off values or potentially triaging positive results so that patients with more bleeding are able to get a colonoscopy earlier. FIT screening does not require any alteration in diet before testing.

Articles of Interest

Colonoscopy vs. Stool-Based Tests: What is the Best Way to Detect Colorectal Cancer?

The stool tests are considered two-step tests, meaning if you get this type of test, it doesn’t tell you whether you have cancer or not. If the results of a stool test are abnormal, it requires a colonoscopy to diagnose what's going on. The colonoscopy confirms whether or not there's a polyp that might be precancerous, or even if there’s cancer. The colonoscopy is important because at that time, tissue samples can be taken, the site can be marked, and it advances the patient's treatment. The stool-based tests, on their own, have to be paired with a colonoscopy to be effective if the result is abnormal.

Fecal immunochemical test (FIT): the pros, cons, and process

A positive FIT test result can indicate that abnormal bleeding is occurring somewhere in the digestive tract. This blood loss could be due to a number of things besides cancer, so if the test finds blood, a colonoscopy will be needed to look for the source. Let your doctor know right away if you have a positive result.

Fecal occult blood test for colorectal cancer screening

FOBT screening offers no benefit without appropriate follow-up diagnostic testing and treatment. It is an indirect screening test that identifies a subgroup of the average-risk, asymptomatic population sufficiently likely to have a clinically important CRC to justify more expensive, invasive diagnostic tests (e.g. colonoscopy). The screening test by itself neither rules in nor rules out colonic neoplasia.

Things to Know About Fecal Occult Blood Tests

Also termed hemoccult tests, fecal occult blood tests employ plant-based testing substances (guaiac) or antibody proteins (immunochemical tests) to uncover the presence of blood in a stool sample.

What Is a Fecal Occult Blood Test?

A guaiac FOBT, also called a gFOBT, tests for heme in a stool sample. Heme is a primary component of hemoglobin, a protein found in red blood cells. Samples from two or three different bowel movements are taken using applicator sticks. The samples are smeared onto guaiac paper, to which hydrogen peroxide is added. The paper will turn blue if heme is present. To avoid false positives, patients may need to avoid foods that contain heme for a few days before testing. This includes red meat, poultry, and seafood. Other foods that may trigger false positives include vitamin C supplements, iron supplements, turnips, and horseradish.

Resources

EZ Detect

The good news is that no one has to die from colon cancer. With over a 90 percent cure rate caught early enough, colon cancer is preventable and treatable. Early detection through screening is the key. Just drop a test tissue into the toilet bowl, read your results within two minutes and flush the tissue. No stool contaminated waste

MayoClinic

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 doesn't indicate potential sources of bleeding.

StatPearls

FOBT may be performed in both inpatient and outpatient settings. In the inpatient setting, stool may be obtained manually during digital rectal examination and applied to heme occult testing cards. In the outpatient setting, the patient typically collects a stool sample at home and submits it to a laboratory.