How FDRs with Familial Risk for CRC can benefit from colonoscopy screening?

First-degree relatives (FDRs) of patients with non-syndromic colorectal cancer (CRC) do not use colonoscopy screening as recommended, with screening completion rates below 50%. Fecal immunochemical testing (FIT) has not yet been assessed for screening uptake in this demographic, despite studies done in FDR who were referred for screening suggesting that FIT was not inferior to colonoscopy regarding diagnostic yield and tumor stage.

In a new study published in PLOS Medicine, scientists examined whether FIT screening uptake in the familial-risk population is superior to colonoscopy screening uptake with an equal effect on CRC detection.

Scientists randomized trials in 12 Spanish centers between February 2016 and December 2021. It involves 870 asymptomatic FDR patients with non-syndromic CRC. Participants were invited to participate through their affected index case(s).

The main goal is to compare screening uptake between colonoscopy and FIT. Another intention is to determine the efficacy of each strategy to detect advanced colorectal neoplasia.

FDR was randomly assigned (1:1) to get a single colonoscopy instead of an annual FIT test for three consecutive years, with a follow-up colonoscopy in the event of a positive test result. The completion percentage of the screenings was comparable for the groups assigned to FIT and colonoscopy screening (36% against 34%, respectively). Compared to participants allocated to get a single colonoscopy, those receiving annual FIT had a considerably lower detection rate of advanced colorectal neoplasia.

The results of this experiment show that FIT cannot increase screening uptake in non-syndromic familial CRC patients. The fact that more than 50% of those who were eligible declined to participate suggests that innovative educational initiatives should be put in place to raise awareness among those who are at risk and their providers.

Journal Reference:

1. González-López N, Quintero E, Gimeno-Garcia AZ, Bujanda L, Banales J, Cubiella J, et al. (2023) Screening uptake of colonoscopy versus fecal immunochemical testing in first-degree relatives of patients with non-syndromic colorectal cancer: A multicenter, open-label, parallel-group, randomized trial (ParCoFit study). PLoS Med 20(10): e1004298. DOI: 10.1371/journal.pmed.1004298