Detection Rate of Colorectal Cancer or Precancer Adenoma by Colonoscopy After 1, 2, or 3 Positive Results via Fecal Immunochemical Testing.

Background: Single-vial fecal immunochemical testing (FIT) is an accepted method of colorectal cancer (CRC) screening. The available 3-vial FIT data set allows for comparison of colonoscopy results using various screening methods.

Objective: To determine the optimal number of vials for a strong FIT-screening program by examining whether using only a single vial impacts the use of colonoscopy for CRC screening.

Methods: Patients were given 3-vial FIT collection kits that were processed with a positive hemoglobin cut-off detection level of 100 ng per mL. If FIT results were positive, colonoscopy testing was performed using standard practices.

Results: Detection of CRC and precursor adenoma was examined in 932 patients, with a positive colonoscopy sensitivity of 56.2% and 3.0% CRC detection after 3-vial FIT; after single-vial screening, those values were 60.9% and 4.7%, respectively.

Conclusions: Prescreening patients with FIT testing before colonoscopy allows colonoscopy testing to be targeted to higher-risk patients. Implementing use of only a single vial from the 3-vial FIT screening kit would reduce the colonoscopy reflex rate, colonoscopy complication numbers, facility costs, and patient distress by more than 40%, compared with 3-vial screening.