327 What to Do When Fecal Immunochemical Test (FIT) Is Positive Following Normal Colonoscopy? Comparison of Adenoma Detection Rate (ADR) of Standard FIT-Colonoscopy and Relook Colonoscopy

Abstract

INTRODUCTION: For average risk patients, current guidelines generally recommend either yearly FIT or colonoscopy every ten years. A positive FIT test triggers reflex colonoscopy, which can have higher ADR than screening colonoscopy. FIT tests are also frequently performed following a negative colonoscopy in routine practice for concerning symptoms or desire for “early relook.” A positive FIT test often leads to reflex “relook colonoscopy” despite negative colonoscopy within the past 10 years. It is not clear if relook colonoscopy would be necessary or lead to new findings. As such, we aimed to compare colonoscopy findings including ADR in the “relook FIT-colonoscopy” versus the “standard FIT-colonoscopy” population. METHODS: This is a retrospective study of 1,940 patients age ≥ 18 at a community medical center between December 1, 2002 and June 1, 2018: 51 had relook FIT-colonoscopy and 1,889 patients had standard FIT-colonoscopy. The primary outcome was ADR with secondary outcomes including other colonoscopy findings. RESULTS: The group receiving relook colonoscopy was on average younger than the standard FIT-colonoscopy group (61.8 v 64.5, P = 0.049). The relook colonoscopy group had lower percentage of males (37.3 v 45.6%, p< 0.001) but higher percentage of Asians (90.2 v 76.5%, p< 0.001). While the relook colonoscopy group had fewer days between FIT and colonoscopy, this was not statistically significant (61.1 v 68.9, P = 0.800). For patients receiving relook colonoscopy, 82.4% were asymptomatic at time of FIT, while 5.9% had bowel habit changes, 5.9% anemia, 3.9% abdominal pain, and 3.9% rectal bleeding. FIT occurred on average 4.9 +1.8 years following colonoscopy. Standard FIT-colonoscopy demonstrated ADR of 51.2% with cancer identified in 1.6% of patients. The relook colonoscopy strategy had ADR of 39.2% (N = 20); 49.0% of patients had no abnormal findings: 47.1% had hemorrhoids, 23.5% had diverticulosis, and none had cancer (Figure 1). Of the 20 patients with adenoma in the relook colonoscopy group, 3 patients had adenoma >1 cm and 2 had advanced neoplastic polyps (villous and serrated). CONCLUSION: While significant data has demonstrated that colonoscopy following positive FIT is important, data on relook colonoscopy is less clear. Given ADR of 37.7%, patients with positive FIT should receive repeat colonoscopy despite prior normal colonoscopy. Nevertheless, more data is needed to determine validity and criteria for pursuing repeat FIT following a normal colonoscopy.