FIT Aids Triage for Possible Colorectal Cancer
FIT sensitivity is maximized to 97.0 percent at a cutoff of 2 μg hemoglobin/g feces
MONDAY, Nov. 2, 2020 (HealthDay News) -- Fecal immunochemical test (FIT) results can be used to prioritize patients for investigation of suspected colorectal cancer (CRC), according to a study published online Oct. 30 in Gut.
Nigel D'Souza, M.B.B.S., from Imperial College London, and colleagues assessed whether FIT could be used to select patients with suspected CRC symptoms for urgent investigation. The analysis included 9,822 patients referred to secondary care with suspected CRC symptoms meeting NHS England criteria for urgent two-week wait pathway referral and triaged to investigation with colonoscopy.
The prevalence of CRC at colonoscopy was 3.3 percent. The researchers found that at cutoffs of 2, 10, and 150 μg hemoglobin/g feces, FIT positivity decreased from 37.2 percent to 19.0 and 7.6 percent, respectively. At these cutoffs, the positive predictive values of FIT for CRC were 8.7, 16.1, and 31.1 percent, respectively. The corresponding negative predictive values were 99.8, 99.6, and 98.9 percent. There were declines noted in the sensitivity of FIT for CRC with increasing cutoffs (97.0, 90.9, and 70.8 percent, respectively), while there were increases seen in specificity (64.9, 83.5, and 94.6 percent, respectively). The investigators found the value for the area under the receiver operating characteristic curve was 0.93.
"The diagnostic accuracy of FIT for CRC is superior to symptoms," the authors write.
All FIT kits and reagents were provided by Alpha Labs.