FIT improves referral efficiency in primary care settings
Fecal immunochemical test improved the efficiency of referrals in patients with new-onset lower gastrointestinal symptoms within a primary health care setting, according to research published in Gut.
“A significant percentage of colorectal cancers are diagnosed in symptomatic patients after the implementation of CRC screening programs. Unfortunately, most symptoms are non-specific at presentation,” Noel Pin-Vieito, Complexo Hospitalario Universitario de Ourense, and colleagues wrote. “In the last few years, evidence has proven that FIT for hemoglobin may be effective in evaluating patients with abdominal symptoms to identify patients at low risk of CRC. ... Furthermore, implementation of FIT as a triage test in primary care with appropriate safety netting may improve the efficiency of referrals without missing cases of relevant bowel disease.”
In a systematic literature review, researchers analyzed 23 studies composed of 69,536 participants (median age 58-72 years; 49%-64.6% women) evaluated for abdominal symptoms in a primary care setting to define the performance characteristics of FIT for CRC detection. Researchers noted a CRC prevalence of 0.3% to 6.2% and a significant colonic lesion prevalence of 2.6% to 31%.
According to study results, FIT as a rule-in test at a threshold of 150 µg Hb/g feces or greater in six studies composed of 34,691 participants had a sensitivity of 64.1% (95% CI, 57.8-69.9) and a specificity of 95% (95% CI, 91.2-97.2); a threshold of 10 µg Hb/g feces in 15 studies composed of 48,872 participants yielded a sensitivity of 87.2% (95% CI, 81-91.6) and a specificity of 84.4% (95% CI, 79.4-88.3) for CRC detection. Compared with a threshold of 10 µg Hb/g feces, less than one additional case of CRC would be missed per 1,000 patients at a threshold of 20 µg Hb/g feces (5 studies; 24,187 participants).
“Implementation of FIT as a triage test in primary care may improve the efficiency of referrals. Thus, FIT is the test of choice to evaluate patients with new-onset lower gastrointestinal symptoms in this setting,” Pin-Vieito and colleagues concluded. “Use of this test as ‘rule in’ at a cut-off value of 150 µg Hb/g feces identifies more than half of CRCs using few resources while an f-Hb concentration below 20 µg Hb/g feces rules out more than 85%.”