Using FIT Thresholds for Priority Triage and Risk Stratification in Resource-Constrained Systems.

Abstract

In many colorectal cancer screening settings, a key issue is no longer whether fecal immunochemical testing (FIT) should guide access to colonoscopy, but how FIT results can be used more effectively to manage limited colonoscopy resources. The article by Wu and colleagues provides important data showing the predictive potential of using quantitative FIT (qFIT) values for subsequent risk of colorectal cancer in a hospital-based screening setting. Although colonoscopy is the gold standard for screening, it is costly, invasive, and becoming increasingly constrained by aging populations, expanded screening eligibility, and an increasing number of postpolypectomy surveillance colonoscopies. Unlike binary positive or negative results, qFIT can provide a more refined measure of fecal hemoglobin and underlying colorectal cancer risk. Higher qFIT values are associated with advanced neoplasia and colorectal cancer, which can allow screening programs to prioritize those at greatest short-term risk for faster follow-up procedures. Evidence suggests that FIT positivity thresholds can be tuned to optimize colonoscopy resources and screening goals. In settings where there is a growing burden of postpolypectomy surveillance colonoscopy, FIT-based triage provides a low-cost strategy to improve efficiency, reduce wait times, and maximize the yield of endoscopy resources. Moving beyond binary FIT toward quantitative or risk-based screening follow-up pathways has the potential to optimize colonoscopy allocation and improve overall screening system performance. See related article by Wu et al., p. 733 .