Long-Term Follow-Up of Targeted Biopsy Yield (LOFTY Study) in Ulcerative Colitis Surveillance Colonoscopy.

We previously performed a randomized controlled trial (RCT) comparing targeted and random biopsy in neoplasia detection in patients with ulcerative colitis (UC), which showed the short-term effectiveness of targeted biopsy with one-time colonoscopy. In this retrospective cohort study, we investigated the long-term effectiveness of targeted biopsy in tertiary care hospitals, using the follow-up data from patients with UC for ≥ 8 years who had enrolled in the initial RCT. The primary outcome was death from colorectal cancer (CRC). Secondary outcomes were advanced neoplasia (CRC or high-grade dysplasia) and colectomy due to neoplasia after the RCT. We compared these outcomes between target and random groups. Data on 195 of the 221 patients (88.2%) enrolled in the previous RCT were collected from 28 institutions between 2008 and 2019. No patients died of CRC in either group, with a median 8.8-year follow-up demonstrating a robustness for targeted biopsy in terms of CRC death prevention. Advanced neoplasia was detected in four and three patients in the target and random groups, respectively. Colectomy was required due to neoplasia in three patients in each group. The chance of developing CRC in patients with a negative colonoscopy was low, and the targeted biopsy appeared effective in this population. Conversely, patients found with low-grade dysplasia at initial RCT have 10-fold higher risk of progression to high-grade dysplasia and/or CRC. Ten extracolonic malignancies were observed during the follow-up, resulting in four deaths. Panchromoendoscopy was used only in 4.6% and targeted biopsy was only performed in 59.1% of colonoscopies. We recommend targeted biopsy rather than > 33 random biopsies in real-world settings under adequate observation by specialists.