The Diagnostic Performance of Fecal Immunochemical Tests for Detecting Advanced Neoplasia at Surveillance Colonoscopy

BACKGROUND & AIMS: An increasing burden on health care resources has resulted in a backlog of individuals requiring colonoscopy, with delays in surveillance possibly detrimental for individuals at increased risk of colorectal cancer (CRC). This study investigated the use of a 2 -sample fecal immunochemical test (FIT) to establish those most likely to have advanced neoplasia (AN) and in need of prioritized surveillance colonoscopy. METHODS: This was a prospective study conducted in the tertiary care setting. Participants completed a 2sample FIT (OC-Sensor, Eiken Chemical Company) within 90 days of surveillance colonoscopy. The sensitivity of FIT for detection of AN (CRC or advanced adenoma) in moderate- and highrisk individuals was determined at fecal hemoglobin thresholds between 2 and 80 mu g/g feces. RESULTS: A total of 766 patients were included (median age, 66.1 years [interquartile range, 58.1 - 72.9]; 49.9% male), with AN detected in 8.6% (66/766, including 5 CRC). For moderate -risk individuals (with prior history of adenoma or a signi fi cant family history of CRC), sensitivity of FIT for AN ranged from 73.5% at 2 mu g/g feces, to 10.2% at 80 mu g/g feces. For high -risk conditions (con fi rmed/suspected genetic syndromes or prior CRC), sensitivity of FIT was similar, ranging from 70.6% at the lowest positivity threshold of 2 mu g/g feces, to 11.8% at 80 mu g/g feces. Independent variables in the whole cohort for association with detection of AN at surveillance colonoscopy were age (odds ratio, 1.03; 95% con fi dence interval, 1.00 - 1.06) and FIT hemoglobin result double dagger 10 mu g/g feces (odds ratio, 1.81; 95% con fi dence interval, 1.04 - 3.16). CONCLUSIONS: The use of FIT before surveillance colonoscopy provides clinicians with insights into the risk of AN. This raises the possibility of a method to triage individuals, facilitating the more ef fi cient management of endoscopic resources.