Efficacy of artificial intelligence for adenoma detection in water exchange colonoscopy: a two-center randomized controlled trial

Abstract

Background

Water exchange and artificial intelligence-based computer-aided detection (CADe) separately improve the adenoma detection rate (ADR) and number of adenomas detected per colonoscopy (APC). We aimed to determine whether combining water exchange with CADe enhanced APC versus water exchange alone.

Methods

This randomized controlled trial was conducted at hospitals in Italy and Taiwan using different CADe devices. Patients aged 45–75 years undergoing colonoscopy for screening, surveillance, or positive fecal blood tests were randomized to either water exchange with CADe assistance or water exchange alone. The primary outcome was APC, with 752 patients planned for randomization.

Results

An interim analysis was conducted on 560 patients (75% of the enrollment target; mean age 59.4 years; male 299; water exchange+CADe 279), with similar baseline characteristics between the two groups. APC was significantly higher with water exchange+CADe compared with water exchange alone (1.39 [95%CI 1.06–1.72] vs. 1.05 [95%CI 0.87–1.23]) with an incidence rate ratio of 1.32 (95%CI 1.14–1.54), representing an absolute increase of 0.34. The observed significant difference led to early trial termination. No significant differences were found in ADR and sessile serrated lesion detection rates between the groups (54.1% vs. 50.2% [P = 0.35] and 3.6% vs. 3.6% [P = 0.99], respectively), but this study was not powered to detect such differences. Withdrawal times and the mean number of non-neoplastic lesions per colonoscopy were comparable.

Conclusions

For water exchange colonoscopy, integrating CADe statistically increased APC without prolonging withdrawal times or causing a concomitant increase in resection of non-neoplastic lesions.

Publication History

Received: 22 February 2025

Accepted after revision: 11 August 2025

Accepted Manuscript online:
11 August 2025

Article published online:
22 September 2025

• References

• 1 Bretthauer M, Løberg M, Wieszczy P. et al. Effect of colonoscopy screening on risks of colorectal cancer and related death. N Engl J Med 2022; 387: 1547-1556
• 2 Schottinger JE, Jensen CD, Ghai NR. et al. Association of physician adenoma detection rates with postcolonoscopy colorectal cancer. JAMA 2022; 327: 2114-2122
• 3 Wieszczy P, Bugajski M, Januszewicz W. et al. Comparison of quality measures for detection of neoplasia at screening colonoscopy. Clin Gastroenterol Hepatol 2023; 21: 200-209.e6
• 4 Denis B, Sauleau EA, Gendre I. et al. Measurement of adenoma detection and discrimination during colonoscopy in routine practice: an exploratory study. Gastrointest Endosc 2011; 74: 1325-1336
• 5 Rex DK, Anderson JC, Butterly LF. et al. Quality indicators for colonoscopy. Am J Gastroenterol 2024; 119: 1754-1780
• 6 Khan R, Ruan Y, Yuan Y. et al. Relative efficacies of interventions to improve the quality of screening-related colonoscopy: a systematic review and network meta-analysis of randomized controlled trials. Gastroenterology 2024; 167: 560-590
• 7 Cadoni S, Falt P, Rondonotti E. et al. Water exchange for screening colonoscopy increases adenoma detection rate: a multicenter, double-blinded, randomized controlled trial. Endoscopy 2017; 49: 456-467
• 8 Fuccio L, Frazzoni L, Hassan C. et al. Water exchange colonoscopy increases adenoma detection rate: a systematic review with network meta-analysis of randomized controlled studies. Gastrointest Endosc 2018; 88: 589-597.e11
• 9 Sánchez-Peralta LF, Bote-Curiel L, Picón A. et al. Deep learning to find colorectal polyps in colonoscopy: a systematic literature review. Artif Intell Med 2020; 108: 101923
• 10 Gimeno-García AZ, Hernández Negrin D, Hernández A. et al. Usefulness of a novel computer-aided detection system for colorectal neoplasia: a randomized controlled trial. Gastrointest Endosc 2023; 97: 528-536.e1
• 11 Desai M, Ausk K, Brannan D. et al. Use of a novel artificial intelligence system leads to the detection of significantly higher number of adenomas during screening and surveillance colonoscopy: results from a large, prospective, US multicenter, randomized clinical trial. Am J Gastroenterol 2024; 119: 1383-1391
• 12 Shaukat A, Lichtenstein DR, Somers SC. et al. Computer-aided detection improves adenomas per colonoscopy for screening and surveillance colonoscopy: a randomized trial. Gastroenterology 2022; 163: 732-741
• 13 Soleymanjahi S, Huebner J, Elmansy L. et al. Artificial intelligence-assisted colonoscopy for polyp detection: a systematic review and meta-analysis. Ann Intern Med 2024; 177: 1652-1663
• 14 Lee MCM, Parker CH, Liu LWC. et al. Impact of study design on adenoma detection in the evaluation of artificial intelligence-aided colonoscopy: a systematic review and meta-analysis. Gastrointest Endosc 2024; 99: 676-687.e16
• 15 Makar J, Abdelmalak J, Con D. et al. Use of artificial intelligence improves colonoscopy performance in adenoma detection: a systematic review and meta-analysis. Gastrointest Endosc 2025; 101: 68-81.e8
• 16 Kaminski MF, Thomas-Gibson S, Bugajski M. et al. Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative. Endoscopy 2017; 49: 378-397
• 17 Hassan C, Badalamenti M, Maselli R. et al. Computer-aided detection-assisted colonoscopy: classification and relevance of false positives. Gastrointest Endosc 2020; 92: 900-904.e4
• 18 Lai EJ, Calderwood AH, Doros G. et al. The Boston bowel preparation scale: a valid and reliable instrument for colonoscopy-oriented research. Gastrointest Endosc 2009; 69: 620-625
• 19 Endoscopic Classification Review Group. Update on the Paris classification of superficial neoplastic lesions in the digestive tract. Endoscopy 2005; 37: 570-578
• 20 Crockett SD, Nagtegaal ID. Terminology, molecular features, epidemiology, and management of serrated colorectal neoplasia. Gastroenterology 2019; 157: 949-966.e4
• 21 World Health Organization. Classification of tumours of the digestive tract. Lyon: IARC Press; 2019
• 22 Gupta S, Lieberman D, Anderson JC. et al. Recommendations for follow-up after colonoscopy and polypectomy: a consensus update by the US Multi-Society Task Force on Colorectal Cancer. Gastrointest Endosc 2020; 91: 463-485.e5
• 23 Ciolino JD, Kaizer AM, Bonner LB. Guidance on interim analysis methods in clinical trials. J Clin Transl Sci 2023; 7: e124
• 24 Togo K, Iwasaki M. Optimal timing for interim analyses in clinical trials. J Biopharm Stat 2013; 23: 1067-1080
• 25 Tang CP, Lin TL, Hsieh YH. et al. Polyp detection and false-positive rates by computer-aided analysis of withdrawal-phase videos of colonoscopy of the right-sided colon segment in a randomized controlled trial comparing water exchange and air insufflation. Gastrointest Endosc 2022; 95: 1198-1206.e6
• 26 Tang CP, Lin TL, Hsieh YH. et al. Real-time computer-aided system to compare adenoma detection and adenoma per colonoscopy rates in water exchange and air insufflation: a randomized controlled study. Gastroenterology 2024; 166: S293-S294
• 27 Bretthauer M, Ahmed J, Antonelli G. et al. Use of computer-assisted detection (CADe) colonoscopy in colorectal cancer screening and surveillance: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement. Endoscopy 2025;
• 28 Foroutan F, Vandvik PO, Helsingen LM. et al. Computer aided detection and diagnosis of polyps in adult patients undergoing colonoscopy: a living clinical practice guideline. BMJ 2025; 388: e082656
• 29 Sultan S, Shung DL, Kolb JM. et al. AGA living clinical practice guideline on computer-aided detection-assisted colonoscopy. Gastroenterology 2025; 168: 691-700
• 30 Halvorsen N, Hassan C, Correale L. et al. Microsimulation modelling study. BMJ Med 2025; 4: e001446
• 31 Djinbachian R, Taghiakbari M, Barkun A. et al. Optimized computer-assisted technique for increasing adenoma detection during colonoscopy: a randomized controlled trial. Surg Endosc 2025; 39: 1120-1127
• 32 Spadaccini M, Hassan C, Rondonotti E. et al. Combination of mucosa-exposure device and computer-aided detection for adenoma detection during colonoscopy: a randomized trial. Gastroenterology 2023; 165: 244-251.e3
• 33 Spadaccini M, Hassan C, Alfarone L. et al. Comparing the number and relevance of false activations between 2 artificial intelligence computer-aided detection systems: the NOISE study. Gastrointest Endosc 2022; 95: 975-981.e1
• 34 Troya J, Sudarevic B, Krenzer A. et al. Direct comparison of multiple computer-aided polyp detection systems. Endoscopy 2024; 56: 63-69
• 35 Vennelaganti S, Cuatrecasas M, Vennalaganti P. et al. Interobserver agreement among pathologists in the differentiation of sessile serrated from hyperplastic polyps. Gastroenterology 2021; 160: 452-454.e1