A computer-aided detection system in the everyday setting of diagnostic, screening and surveillance colonoscopy: an international, randomized trial.

BACKGROUND AND STUDY AIM: Computer-aided detection (CADe) has been developed to improve detection during colonoscopy. After initial reports of high efficacy, there has been an increasing recognition of variability in the effectiveness of CADe systems. The aim of this study was to evaluate a CADe system (PENTAX Medical, Tokyo, Japan) in a varied colonoscopy population. PATIENTS AND METHODS: A multicenter, randomized trial was conducted at 7 hospitals (both university and non-university) in Europe and Canada. Participants referred for diagnostic, non-iFOBT screening, or surveillance colonoscopy were randomized (1:1) to undergo CADe-assisted or conventional colonoscopy (CC) by experienced endoscopists. Participants with insufficient bowel preparation were excluded from the analysis. Primary outcome was adenoma detection rate (ADR). Secondary outcomes included adenomas per colonoscopy (APC) and sessile serrated lesions per colonoscopy (SSLPC). RESULTS: In total, 581 participants were enrolled, of which 497 were included in the final analysis: 250 in the CADe-arm and 247 in the CC-arm. Surveillance was the indication in 202/497 (40.6%) colonoscopies, diagnostic in 199/497 (40.0%), and non-iFOBT screening in 96/497 (19.3%). Overall, ADR (38.4% vs. 37.7%; p=0.43) and APC (0.66 vs. 0.66; p=0.97) were similar between CADe and CC. SSLPC was increased (0.30 vs. 0.19; p=0.049) in the CADe-arm vs. CC. CONCLUSIONS: In this study conducted by experienced endoscopists, CADe did not result in a statistically significant increase in ADR. However, the ADR of our control group substantially surpassed our sample size assumptions, increasing the risk of an underpowered trial. (Trialsearch.who.int:NL9135).

A computer-aided polyp detection system in screening and surveillance colonoscopy: an international, multicentre, randomised, tandem trial.

BACKGROUND: Studies on the effect of computer-aided detection (CAD) in a daily clinical screening and surveillance colonoscopy population practice are scarce. The aim of this study was to evaluate a novel CAD system in a screening and surveillance colonoscopy population. METHODS: This multicentre, randomised, controlled trial was done in ten hospitals in Europe, the USA, and Israel by 31 endoscopists. Patients referred for non-immunochemical faecal occult blood test (iFOBT) screening or surveillance colonoscopy were included. Patients were randomomly assigned to CAD-assisted colonoscopy or conventional colonoscopy; a subset was further randomly assigned to undergo tandem colonoscopy: CAD followed by conventional colonoscopy or conventional colonoscopy followed by CAD. Primary objectives included adenoma per colonoscopy (APC) and adenoma per extraction (APE). Secondary objectives included adenoma miss rate (AMR) in the tandem colonoscopies. The study was registered at ClinicalTrials.gov, NCT04640792. FINDINGS: A total of 916 patients were included in the modified intention-to-treat analysis: 449 in the CAD group and 467 in the conventional colonoscopy group. APC was higher with CAD compared with conventional colonoscopy (0·70 vs 0·51, p=0·015; 314 adenomas per 449 colonoscopies vs 238 adenomas per 467 colonoscopies; poisson effect ratio 1·372 [95% CI 1·068-1·769]), while showing non-inferiority of APE compared with conventional colonoscopy (0·59 vs 0·66; p<0·001 for non-inferiority; 314 of 536 extractions vs 238 of 360 extractions). AMR in the 127 (61 with CAD first, 66 with conventional colonoscopy first) patients completing tandem colonoscopy was 19% (11 of 59 detected during the second pass) in the CAD first group and 36% (16 of 45 detected during the second pass) in the conventional colonoscopy first group (p=0·024). INTERPRETATION: CAD increased adenoma detection in non-iFOBT screening and surveillance colonoscopies and reduced adenoma miss rates compared with conventional colonoscopy, without an increase in the resection of non-adenomatous lesions. FUNDING: Magentiq Eye.

The Workgroup Serrated Polyps and Polyposis (WASP) classification for optical diagnosis of colorectal diminutive polyps with iScan and the impact of the revised World Health Organization (WHO) criteria.

BACKGROUND AND AIMS: The Workgroup Serrated Polyps and Polyposis (WASP) developed criteria for optical diagnosis of colorectal polyps. The aims of this study were: (1) to improve optical diagnosis of diminutive colorectal polyps, especially SSLs, after training endoscopists in applying WASP criteria on videos of polyps obtained with iScan and (2) to evaluate if the WASP criteria are still useful when polyps are pathologically revised according to the World Health Organization (WHO) 2019 criteria. METHODS: Twenty-one endoscopists participated in a training session and predicted polyp histology on 30 videos of diminutive polyps, before and after training (T0 and T1 ). After three months, they scored another 30 videos (T2 ). Primary outcome was overall diagnostic accuracy (DA) at T0 , T1 and T2 . Polyps were histopathologically classified according to the WHO 2010 and 2019 criteria. RESULTS: Overall DA (both diminutive adenomas and SSLs) significantly improved from 0.58 (95% CI 0.55-0.62) at T0 to 0.63 (95% CI 0.60-0.66, p = 0.004) at T1 . For SSLs, DA did not change with 0.51 (95% CI 0.46-0.56) at T0 and 0.55 (95% CI 0.49-0.60, p = 0.119) at T1 . After three months, overall DA was 0.58 (95% CI 0.54-0.62, p = 0.787, relative to T0 ) while DA for SSLs was 0.48 (95% CI 0.42-0.55, p = 0.520) at T2 . After pathological revision according to the WHO 2019 criteria, DA of all polyps significantly changed at all time points. CONCLUSION: A training session in applying WASP criteria on endoscopic videos made with iScan did not improve endoscopists' long-term ability to optically diagnose diminutive polyps. The change of DA following polyp revision according to the revised WHO 2019 criteria suggests that the WASP classification may need revision.

Application of a novel self-assembling peptide to prevent hemorrhage after EMR, a feasibility and safety study.

BACKGROUND: A novel self-assembling peptide (SAP) can be applied to the post-endoscopic mucosal resection (EMR) defect to treat oozing bleedings. It has been suggested to stimulate early healing of damaged vessels. We hypothesized that SAP application could prevent delayed bleeding (DB) after EMR and performed a prospective cohort study to determine feasibility and safety. METHODS: A total of 48 consecutive patients who underwent EMR between June 2018 and August 2019 for large lesions in the esophagus, duodenum (> 1 cm) or colorectum (> 2 cm) were treated with adjuvant SAP application. Duration and ease of SAP application were measured, as well as DB outcome. RESULTS: The EMR defects of 48 patients were treated with SAP; 17 in the esophagus, 13 in the duodenum and 18 in the colorectum. SAP was easy to apply on the EMR defect with a median duration of 2.0 min. A dose of 3 cc was generally enough to cover a defect between 10 and 50 mm. An exploratory analysis of the prophylactic ability of SAP showed that 15.9% of patients (7/44) treated with SAP still had a DB, mostly in the duodenum (4/11). No adverse events related to gel exposure were reported. CONCLUSIONS: SAP application after EMR was found to be feasible and safe, and did not delay the procedure; however, DB was still relatively common. Future comparative studies are needed to evaluate whether SAP is able to reduce DB after EMR, particularly for lesions with an increased bleeding risk, such as in the duodenum.

Risk factors and clinical outcomes of endoscopic dilation in benign esophageal strictures: a long-term follow-up study.

BACKGROUND AND AIMS: Endoscopic dilation (ED) is still the mainstay of therapeutic management of benign esophageal strictures (BESs). This study aimed to establish risk factors for refractory BESs and assess long-term clinical outcomes of ED. METHODS: We performed a retrospective study in 891 patients who underwent ED from 2003 to 2018 for BESs. We searched electronic medical records in 6 tertiary care centers in the Netherlands for data on clinical outcome of ED. Median follow-up was 39 months. The primary endpoint was risk factors for refractory BESs, defined as factors associated with an increased number of ED sessions during follow-up. Secondary endpoints were time from first to last ED session and adverse events. RESULTS: Dilation up to 13 to 15 mm was associated with a higher number of ED sessions than dilation up to 16 to 18 mm (5.0 vs 4.1; hazard ratio [HR], 1.4; P = .001). Compared with peptic strictures, anastomotic (4.9 vs 3.6; HR, 2.1; P < .001), radiation (5.0 vs 3.6; HR, 3.0; P < .001), caustic (7.2 vs 3.6; HR, 2.7; P < .001), and postendotherapy (3.9 vs 3.6; HR, 1.8; P = .005) strictures were associated with a higher number of ED sessions. After 1 year of follow-up, the proportions of patients who remained free of ED was 75% in anastomotic, 71% in radiation, 70% in peptic, 83% in postendotherapy, and 62% in caustic strictures. Esophageal perforation occurred in 23 ED sessions (.4%) in 22 patients (2.4%). CONCLUSIONS: More than 60% of patients with BESs remain free of ED after 1 year of follow-up. Because dilation up to 16 to 18 mm diameter was associated with fewer ED sessions during follow-up, we suggest that clinicians should consider dilation up to at least 16 mm to reduce the number of ED sessions in these patients.