Adding family history to faecal immunochemical testing increases the detection of advanced neoplasia in a colorectal cancer screening programme

Background: Faecal immunochemical testing (FIT) for colorectal cancer (CRC) screening has suboptimal sensitivity for detecting advanced neoplasia. To increase its performance, FIT could be combined with other risk factors. Aim: To evaluate the incremental yield of a screening programme using a positive FIT or a CRC family history, to offer a diagnostic colonoscopy. Methods: For this post hoc analysis, data were collected in the colonoscopy arm of a colonoscopy or colonography for screening study. In this study, 6600 randomly selected, asymptomatic men and women (50–75 years) were invited for screening colonoscopy. 1112 Participants completed a FIT and a questionnaire prior to colonoscopy. We compared the yield of FIT-only and FIT combined with CRC family history, defined as having one or more first-degree relatives with CRC. Results: At a 10 μg Hb/g faeces FIT-positivity threshold the combined strategy would increase the yield from 36 (3.2%; CI: 2.4–4.5%) to 53 (4.8%; CI: 3.7–6.2%) cases of advanced neoplasia, at the expense of 148 additional negative colonoscopies. Sensitivity in detecting advanced neoplasia would increase from 36% (CI: 26–46%) to 52% (CI: 42–63%), whereas specificity would decrease from 93% (CI: 92–95%) to 79% (CI: 76–81%). The strategy will be preferred if one accepts 8.8 false positives for every additional participant in whom advanced neoplasia can be detected. Conclusions: Offering colonoscopy to those with a positive FIT or CRC family history increases the yield of a FIT-based screening programme. Depending on the number of negative colonoscopies one accepts, this combined approach can be considered for improving CRC screening.