Test for bacterial markers reduces FIT false-positives
A non-invasive colorectal cancer screening tool based on bacterial fecal biomarkers can help reduce false-positive results when used with a fecal immunochemical test, according to study results.
Jesús Garcia-Gil, PhD, of The Universitat de Girona in Spain, and colleagues wrote that they sought to develop this new tool — called risk assessment of intestinal disease for colorectal cancer (RAID-CRC) — based on emerging evidence of the impact of bacteria on the development of CRC.
“Recently, it has been proven that bacterial communities in the intestinal mucosa of CRC patients are different from those of healthy individuals,” they wrote. “Evidences suggest that gut microbiota may play an important role in CRC pathogenesis.”
To evaluate the new test, researchers performed FIT and RAID-CRC tests on patients who all showed symptoms of CRC that had either normal colonoscopy (n = 167), non-advanced adenomas (n = 88), advanced adenomas (n = 30) or CRC (n = 48).
In their initial assessment of the FIT, researchers found that it had a sensitivity of 83% and specificity of 80%, while the positive and negative predictive values were 56% and 94%, respectively.
When they combined both tests, they found that sensitivity and specificity were 80% and 90%, respectively, and the positive and negative predictive values were 70% and 94%, respectively. Overall, the addition of the RAID-CRC test resulted in a 50% reduction in the false-positive rate.
“RAID-CRC is a promising tool for CRC screening because it may achieve a similar sensitivity as the current methodology used in most of the CRC-screening programs, with a higher specificity and [positive predictive value],” Garcia-Gil and colleagues wrote. “We will seek validation in a screening setting.” – by Alex Young
Disclosures: Garcia-Gil reports receiving grants from MINECO and CDTI and is an employee of GoodGut. Please see the full study for all other authors’ relevant financial disclosures.